Surface-Supplied Diving Handbook MT92 - Book 1 PDF

Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 1 of 336  Page left blank intentionally Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 2 of 336  This...

Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 1 of 336  Page left blank intentionally Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 2 of 336  This document is book number one of the ensemble of three books constituting the “Surface-supplied diving handbook using MT 92 tables” described underneath. Books Description Book #1: This document describes the accidents linked to surface-supplied diving and the Description and prevention of diving procedures to solve and avoid them. accidents The document describes the scope of surface supplied diving procedures, the MT92 decompression tables, and some elements to consider when organising a Book #2: surface supplied diving project such as the necessary personnel, organization of Definition and elements for the maintenance of the diving system, weather conditions, surface supports, preparation systems of communications, work procedures with ROV, documents that must be available, etc. Book #3: This document describes procedures for safe air and nitrox dives using in-water Air and nitrox procedures using air decompression, in-water nitrox decompression, in-water oxygen in-water & surface decompression decompression at 6 m, and surface oxygen decompression. Complementary books that have not yet been published but are planned shortly. Diving using SCUBA replacement systems has widely evolved throughout the years. A particular organization is necessary for these operations, whose Book #4: limitations are more stringent than normal surface-supplied diving operations Air & nitrox diving procedure using and require specific diving systems. In addition, these procedures include the scuba replacement conception or the organization of relevant surface supports, and this aspect of the organization is essential. For these reasons, it appears logical to describe the organization of such operations in a separate book. Wet bells provide numerous advantages over diving baskets when they are well- designed. That includes bells that are sufficiently light and as compact as baskets Book #5: to be easily operated from lightweight surface supports, which is not the case for Air & nitrox procedures using O2 many units currently in use. In addition to setting up the elements for designing decompression in wet bell adequate wet bells, the document will provide procedures for using them and their limitations. This document has been generated by CCO ltd - 52/2 moo 3 tambon Tarpo 65000 Phitsanulok - THAILAND The contents of this document are protected by a copyright and remains the property of CCO Ltd. This handbook exists for the sole and explicit purpose to present guidelines, which have been published by competent bodies, and which we consider as being relevant to commercial diving. CCO Ltd is responsible for the administration and publication of this document. Please note that whilst every effort has been made to ensure the accuracy of its contents, neither the authors, nor CCO Ltd will assume liability for any use thereof. Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 3 of 336  Important Note This book is written with the only aim of informing people interested in diving activities of elements to take into account to prepare safe and successful diving operations. I express my sincere thanks to the people who are supporting this project and provided me with useful documents and advice, particularly Jean Pierre Imbert (Divetech) and doctor Jean Yves Massimelli. Kindly note that this document does not replace specialized diver medical courses. Christian CADIEUX - Author Revision Date Elements modified or added Revision 1 20/11/22 Document published Updated the topic “Adverse effects of hyperbaric oxygen” with the Equivalent Surface Oxygen Time Revision 2 09/08/23 (ESOT), a concept based on the revision of Arieli’s K concept by doctors Risberg and van Ooij, also published in DMAC 35. Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 4 of 336  Page left blank intentionally Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 5 of 336  Table of contents A - Summary of the diving accidents - Purpose (page 10) - List (page 10) B - Elements of anatomy and physiology - Cell (page 22) - Skeletal system (page 26) - Muscular system (page 30) - Skin (page 35) - Nervous system (page 37) - Circulatory and respiratory systems (page 44) - Digestive and urinary systems (page 57) C - Accidents linked to air & surface gas diving - Hypothermia (page 69) - Cold shocks (page 72) - Hyperthermia (page 73) - Sinus barotrauma (page 76) - Ear barotrauma (page 77) - Teeth barotrauma (page 80) - Helmet squeeze and nips (page 81) - Adverse effects of hyperbaric oxygen (page 83) - Narcosis (page 108) - Hypoxia & anoxia (page 110) - Hypercapnia (page 112) - Drowning (page 116) - Pulmonary barotrauma (page 119) - Decompression accidents (page 126) - Isobaric inert gas counterdiffusion (page 151) - Compression arthralgia (page 153) - Hydrocarbons (page 154) - Hydrogen sulfide (H2S) (page 159) - Carbon monoxide (page 163) - Treatment of various diseases using hyperbaric oxygen (page 166) Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 6 of 336  - Cleaning fluids and other pollutants (page 170) - Water contamination by chemicals and radiations (page 176) - Pathogen attacks (page 180) - Acute otitis externa (page 192) - Harmful noises (page 194) - Underwater explosion (page 206) - High pressure water jet injuries (page 209) - Electrical shocks (page 212) - Venomous and aggressive animals (page 220) - Seasickness (page 242) D - Medical tables US Navy revision 7 - Introduction (page 246) - Description and method of use (page 246) - Life support personnel (page 262) - Chamber control (page 263) - Post treatment procedures (page 270) E - Therapeutic tables COMEX - Presentation (page 275) - Charts (page 284) F - Medical equipment checklist, recording data forms, and UPTD tables - DMAC 15 (page 289) - DMAC 1 (page 300) - Medical table record form (page 321) - Emergency contacts (page 322) - Unit Pulmonary Toxic Doses (UPTD) tables as calculated by Doctor W. Brandon Wright (page 323) G - Bibliography Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 7 of 336  Page left blank intentionally Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 8 of 336  Part A - Summary of diving accidents - Purpose (page 10) - List of accidents by symptoms (page 10) ○ Hypothermia (page 10) ○ Cold shocks (page 10) ○ Hyperthermia (page 10) ○ Sinus barotrauma (page 10) ○ Ear barotrauma (page 10) ○ Teeth barotrauma (page 11) ○ Squeeze & nips (page 11) ○ Acute O2 poisoning (page 11) ○ Chronic O2 poisoning (page 11) ○ Narcosis (page 11) ○ Hypercapnia (page 11) ○ Hypoxia (page 12) ○ Anoxia (page 12) ○ Drowning (page 12) ○ Pulmonary barotrauma (page 12) ○ Mediastinal and subcutaneous emphysema (page 12) ○ Pneumothorax (page 12) ○ Arterial Gas Embolism (page 12) ○ Decompression Illness - Type 1 (Skin itching, rash, pain only) (page 12) ○ Decompression Illness - Type 2 (Spinal, Cerebral, Vestibular) (page 12) ○ Compression arthralgia (page 13) ○ Hydrocarbons (page 13) ○ Hydrogen sulfide (H2S) (page 13) ○ Carbon monoxide (page 13) ○ Cleaning fluids (page 13) ○ Water contamination by chemicals and radiations (page 13) ○ Pathogen attacks (page 14) ○ Harmful noises (page 15) ○ Underwater explosion (page 15) ○ Electrical shocks (page 16) ○ Venomous and aggressive animals (page 16 to 19) Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 9 of 336  Hyperlink Tables of contents Purpose This summary identifies accidents and illnesses linked to diving activities by their main symptoms. Note that diseases or accidents that are not of the same origin can have similar symptoms. For this reason, symptoms should not be used alone but associated with other elements, such as the working conditions, the dive profile, the victim's physical condition, etc., to try identifying their origin. That highlights the importance of the diving medical specialist, who must be contacted in priority for any abnormal condition. More details about these accidents are developed in point “C - Accidents linked to saturation diving”. Symptoms linked to diving accidents. Symptoms Possible accident Possible causes - Speech impairment - Body T° equal or less than 35° (death - Fixed ideas occurs at 25°) - Sluggish reactions - Too long time in cold water with an - Confusion inappropriate suit, or insufficient hot - Irritability Hypothermia water delivery to a hot water suit. - Amnesia - Muscular rigidity - Collapse , fainting - If nothing is done: death - Due to insufficient thermal protection when launching the dive or the suit - Rapid breath rate and spasmodic opening suddenly at depth. respiration when reaching the water or Cold shock - Not to be confused with suddenly at depth in cold water hyperventilation due to worrying, which often starts before launching the dive. - Headache - Dizziness - Dry skin - Hot and flushed ( red skin) The victim's core temperature is equal - Dilated pupils to or greater than 39°, usually as a - Confusion Hyperthermia result of a too-warm environment. - Shallow and fast breathing - Weakness - Convulsions - Rapid and weak pulse - Collapse and loss of consciousness - Pain in the forehead - Pain in the cheek area - Bleeding nose Sinus Barotrauma Infection or irritation of the sinuses - Inability to clear the ears - Pain in the ear Barotrauma of the external - Bad equilibration during compression - Red color eardrum ear - Blockage of the eustachian tube - Impaired hearing - Pain under the ear - Bad equilibration during compression Barotraumas of the middle - High-frequency noises - Blockage of the eustachian tube - Loss of hearing ear - Oval or/and round windows damaged Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 10 of 336  Hyperlink Tables of contents Symptoms linked to diving accidents. (continuation) Symptoms Possible accident Possible causes - Upset balance - Vertigo , Nausea - Bad equilibration during compression - Affected hearing Eardrum rupture - Blockage of the eustachian tube - If using face mask with the ears - Water intrusion in the middle ear exposed to the water: Sudden vertigo followed by stabilization - Pain under the ear - Bad equilibration - High frequency noises (tinnitus) - Blockage of the eustachian tube Barotraumas of the inner - Dizziness - Oval or/and round windows damaged - Nausea ear or ruptured - Loss of hearing - Cochlea damaged - Pain in the maxillaries, mostly during ascent Teeth barotrauma - Breathing gas trapped in the teeth - Suction into the helmet in case of no - Chest pain return valve failure resulting in - Bleeding lungs depression in the helmet - Difficulty breathing - Often associated with continuous flow - Pain in the neck and the shoulders Squeeze helmets (Can lead to Pulmonary - Bleeding ears barotraumas associated with - Hemorrhages of the eyes and the nose fractures of the ribs and /or collar - Bruised and puffy cheeks bones in severe cases) - Due to the external pressure on the suit, creating folds which will trap - Bruising of the skin Nips and pinch the skin - Often associated with dry suits - Visual disturbance (tunnel vision) - Nausea - Too elevated oxygen partial pressure - Hearing problems - Twitching Acute oxygen poisoning - Diver suffering from intolerance to (Paul Bert effect) oxygen - Irritability - Dizziness - Convulsions After a long time under oxygen : - Dry irritated throat - Tight feeling in the chest - Dry, painful cough Chronic oxygen poisoning - Oxygen breathed at a partial pressure - Painful fingertips (Lorrain Smith effect) above 0.5 bars during long periods - Shortness of breath - Mild tingling in the lungs followed by burning sensation. In the water or in chamber: - Exaggerated euphoria or anxiety - Lack of memory - Too elevated partial pressure of - Irritability nitrogen (air diving). - Hallucinations Narcosis - Narcotic gas in the mix (nitrogen, - Lack of coordination argon, etc.) - Sudden panic - 1st visible symptoms around 30 m with air diving. - Headache - Too elevated CO2 partial pressure in - Increased breathing the blood (over 0,059 / 45 mm hg) - Superficial breath Hypercapnia - Feeling apprehension - Panic Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 11 of 336  Hyperlink Tables of contents Symptoms linked to diving accidents. (continuation) Symptoms Possible accident Possible causes - Cyanosis, bluish tinge - Poor coordination - Oxygen Partial pressure below 160 - Breath increased Hypoxia mb - Increased heart rate - Loss of conscious - Death follows quickly Anoxia - No oxygen in the breathing mix - Increased respiratory rate. - Airways invaded by a liquid - Casualty vomiting - Pulmonary oedema Drowning The symptoms are linked to catastrophic events during the dive - Unconsciousness - Difficulty breathing - Pain behind the breastbone Mediastinal emphysema - Gas trapped in the space between the (Pulmonary barotrauma) lungs - Sensation of fullness Symptoms in addition to those listed above: Mediastinal emphysema - Gas trapped below the skin near - Gas trapped in the mediastinal space shoulders and around the neck with subcutaneous also trapped under the skin of the - Hoarse voice emphysema shoulders and neck - Sensation of fullness of the throat (Pulmonary barotrauma) - Chest pain - Restricted chest movements - Gas trapped within the pleura - Difficulties breathing Pneumothorax NB: In slight cases can be only detected - Chest moving without venting (Pulmonary barotrauma) by X rays - Blood vessels of the neck may be swollen Generally, 5 to 10 min after surfacing: - Headache , dizziness - Visual disturbance - Confusion, hallucinations - Gas bubbles entering the blood - Loss of coordination Arterial Gas Embolism vessels affecting the nervous system (AGE) - Abnormal gait and the circulatory system - Paralysis - Collapse - Symptoms similar to infracts - Skin itching Skin only decompression - Pathogen bubbles in the small vessels - Rash under the skin accident (classified type 1) under the skin - Localized non-radiating pain, generally Pain only decompression - Bubbles trapped in or around joints in a joint (elbow, wrist, knee, etc.) accident (classified type 1) Radiating pain - Radiating pain in the shoulders or the - Bubbles trapped In the spinal cord. limbs Spinal decompression The affected area depends on the - Girdle Pain in the lumbar area accident (classified type 2) location of the bubble in the spinal - Numbness, tingling cord - Decreased sensation to touch - Paraplegia/paralysis - Loss of bladder and bowel control - Vertigo - Bubbles in the cochlea, the - Loss of hearing Vestibular decompression vestibulocochlear nerves, the - Nausea accident (classified type 2) cerebellum or cortical pathways. - Nystagmus (also called dancing eyes) - Headache , dizziness Cerebral decompression - Pathogen bubbles trapped in the See the continuation on the next page accident (classified type 2) brain Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 12 of 336  Hyperlink Tables of contents Symptoms linked to diving accidents. (continuation) Symptoms Possible accident Possible causes Continuation of the previous page - Visual disturbance - Confusion, hallucinations Cerebral decompression - Pathogen bubbles trapped in the - Loss of coordination accident (classified type 2) brain - Abnormal gait - Paralysis of one side of the body - Collapse - Deep aching pains - Gritting and popping within the joints - It is thought to result from the - Symptoms may occur around 30 metres sudden increase in tissue gas tension at rapid compression rates surrounding the joints causing fluid - At a slow compression rate, symptoms Compression arthralgia shifts and interfering with joint are not present before 90 metres lubrication. - The symptoms usually disappear in - Often linked to too fast compression reverse order during the ascent. - Burning sensation on swallowing - Nausea and vomiting - Abdominal cramps - Weakness - Anesthesia - Hallucinations Hydrocarbons intoxication Ingestion or breathing of hydrocarbons - Changes in color perception - Blindness - Seizures - Coma - Eye and respiratory tract irritation - Loss of smell - Headache and nausea - Loss of reasoning Hydrogen sulfide (H2S) - Hydrogen sulfide breathing - Loss of balance - Unconsciousness - Breathing will stop within minutes - Headache - Dizziness - Nausea Carbon monoxide poisoning - Carbon monoxide breathing - Loss of consciousness - Death if nothing is done following maintenance of the air/gas supply system - Nausea, vomiting and abdominal cramps. Contaminants into the chamber, gas - Weakness Cleaning fluids piping, and/or the gas storage.. - Anaesthesia - Blindness - Coma - Upper respiratory flu or cold like symptoms - Coughing - Vomiting Some chemical contaminants easily - Diarrhea Contamination by blend with the water and can enter in - Pneumonia chemicals the body by ingestion, inhalation, or - Headaches contact with the skin - Dizziness - Skin lesions See the continuation on the next page Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 13 of 336  Hyperlink Tables of contents Symptoms linked to diving accidents. (continuation) Symptoms Possible accident Possible causes Continuation of the previous page - Headache - Visual disturbances Some chemical contaminants easily - Paralysis, blend with the water and can enter in - Convulsions Contamination by chemicals the body by ingestion, inhalation, or - Loss of conscious contact with the skin (When diving in rivers, lakes, ports or near some polluted facilities ) - Rash - Itchy skin. - Fever or chills - Muscle aches - Allergic reaction, Most parasites are acquired by - Cough / asthmatic attack. - Nausea & vomiting, Contamination by parasites ingestion, but some gain entry into the body by skin contact. - Diarrhea, - Blood in urine - Loss of weight - Jaundice - Nervous manifestation - Dry mouth - Difficulties swallowing - Nausea & vomiting - Abdominal cramps/diarrhea - Jaundice - Faeces with blood Bacteria can be found in almost any - Difficulties in breathing environment and sometimes - Fever & dehydration Contamination by Bacteria concentrate in a thin layer on the - Nose bleeds water surface, or a thin layer on the - Vision troubles/hallucinations top of sediment. - Ear canal pains and swellings - Fickle mood - Fatigue/lethargic feeling - Muscle weakness/cramps - Collapses - Gastrointestinal disturbances - Weight loss - Headache - Fever, - Delirium, Viruses are the smallest pathogen - Seizures agents. They are difficult to detect - Difficulty breathing Contamination by Virus and treat. - Sore throat - Cough - Fatigue & Lethargy - Myalgia - Paralysis - Death - Nausea & vomiting - Diarrhea - Skin burns (skin reddening) - Weakness - Lethargy and fatigue Exposure to radiations - Loss of appetite (anorexia) - Fainting See the continuation on the next page Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 14 of 336  Hyperlink Tables of contents Symptoms linked to diving accidents. (continuation) Symptoms Possible accident Possible causes Continuation of the previous page - Dehydration - Inflammation of tissues (swelling, redness or tenderness) - Hemorrhages under the skin Direct exposure to radioactive - Bleeding from your nose, gums or Irradiation materials mouth - Anemia - Hair loss (usually from just the scalp) - Decrease in platelets - Death can happen quickly - Tinnitus - Difficulty of hearing in noisy areas - Sensation of muffling - Difficulties understanding words, especially when there is background noise - The need to ask others to speak more Exposure to: slowly, clearly and loudly - Noisy tools - Memory disturbances Hearing loss - Noisy surrounding - Intellectual impairment - Sonar - Depression - Permanent sensorineural hearing loss - Dizziness - Nausea - Symptoms occur after diving in noisy surrounding - Blurred vision - Lightheadedness - Vibratory sensations in hands, arms and Diving operations in noisy legs - Tremors in upper extremities. Harmful noises surroundings or in the vicinity of boats using low frequency sonar - Pain cochleo-vestibular - Change in rate of respiration - Skin tension - Sudden acute abdominal pain like a kick in the stomach. - Transient paralysis of the lower limbs - Nausea, vomiting (with or without blood) - Sensation of an electric current passing through the body - Testicular pain - Chest discomfort followed by In an underwater explosion, the expectoration of blood or sputum Underwater explosion surrounding water doesn't absorb the (hemoptysis) and hiccups pressure but moves with it. - Tachycardia - Cyanosis - Mild to severe shock - Loss of hearing - Disorientation - Delirium - Unconsciousness - Amnesia - Rectal bleeding may be apparent. - Death can occur quickly Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 15 of 336  Hyperlink Tables of contents Symptoms linked to diving accidents. (continuation) Symptoms Possible accident Possible causes - Hypertension - Tachycardia - Dysrhythmias, ventricular fibrillation, Asystole - Impaired ventilation - Hypo - Fractures ( due to muscular contraction) Exposure to electricity and electrical - Motor deficit Electric shock fields - Sensory deficit - Problems hearing - Shock - Loss of conscious - Coma - Death - Insufficient skin protection/ - Cuts or abrasion of the skin Coral cuts Inappropriate diving suit - Intense pain - Nausea and vomiting for two to three hours - Insufficient skin protection / - Small welts on the skin with red lesions Contact with fire coral Inappropriate diving suit - Swelling, blisters, and pus-filled incrustations - Itching or welts remaining on the skin - Small linear eruptions that develop rapidly at times surrounded by a raised inflammation - Blisters or even necrotic ulcers - Weakness - Nausea - Insufficient skin protection / - Headache Contact with anemone Inappropriate diving suit - Muscle pain and spasms - Abundant tears and nasal discharge - Increased sweating - Changes in pulse rate - Chest pain - Dermal irritation - Abnormal increase in sensitivity to stimuli of the sense, and sensation of tingling, tickling, prickling, pricking, or - Insufficient skin protection / burning Contact with sponge Inappropriate diving suit - Redness of the skin due to increased blood flows of the capillaries, with or without papule and vesicle development - Insufficient skin protection / - Spines with pain Contact with ea urchin Inappropriate diving suit - Inflamed and swollen region, sometimes white and ischaemic (Insufficient blood supply), with a - Insufficient skin protection/ cyanotic area surrounding it Poisoning by cone shell Inappropriate diving suit - Numbness and tingling in the whole (Sting) body, and especially the mouth and - Inappropriate handling lips (10 minutes to develop) See the continuation on the next page Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 16 of 336  Hyperlink Tables of contents Symptoms linked to diving accidents. (continuation) Symptoms Possible accident Possible causes Continuation of the previous page - Skeletal muscular paralysis that may spread from the site of injury - Difficulty with swallowing and speech. - Double and blurred vision (paralysis of voluntary muscles and pupillary - Insufficient skin protection/ reactions) Poisoning by cone shell Inappropriate diving suit - Respiratory paralysis with shallow rapid (Sting) breathing and a cyanotic appearance - Inappropriate handling preceding apnea, unconsciousness and death. - Cardiac failure - If the patient survives, he/she is active and mobile within 24 hours. - Pain increasing in intensity, often coming in waves. - Multiple interlacing whiplash lines red, purple, or brown, 0.5 cm wide - Patient confused, acting irrationally - Consciousness disturbance. - Hypotension, tachycardia, and a raised venous pressure - Coma and death - Clinical state oscillating from hypertension episodes, tachycardia, rapid respiration, and normal venous Contact with Box jelly fish - Insufficient skin protection/ pressure to those of hypotension, Inappropriate diving suit bradycardia, apnea, and elevated venous pressure. - Respiratory distress, pulmonary congestion, oedema, and cyanosis may be due to cardiac effects or a direct midbrain depression. - If death occurs, it usually does so within the first 10 minutes; survival is likely after the first hour. - Amnesia - Paralysis and abdominal pains. Symptoms visible after a latent period from 10 minutes to several hours - 4 to 20 teeth marks - Euphoria, anxiety, or restlessness. - Thirst, dry throat, nausea, and vomiting - Generalized stiffness and aching - Muscle weakness - Paralysis that extends centrally from the area of the bite - Muscular twitching, writhing, and - Insufficient skin protection spasms Bitten by sea snake - Improper behaviour - Difficulty to speak and swallow - Paralysis may extend to the bulbar areas - Facial and ocular paralysis may develop. - Necrosis of muscles and damage in the kidneys that may develop in several hours - Respiratory distress, shortness of breath, cyanosis, and finally, death. Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 17 of 336  Hyperlink Tables of contents Symptoms linked to diving accidents. (continuation) Symptoms Possible accident Possible causes - Excruciating pain that increases in severity and sometimes comes in waves. - unconsciousness - Ischemia of the area is followed by cyanosis - Area swollen and edematous, often hot, with numbness in the centre and extreme tenderness around the periphery - Insufficient skin protection - Paralysis of the adjacent muscles immobilizing the limb. Poisoning by stone fish - Improper behaviour - Pain likely to spread proximally - Animal not seen - Cardiac failure like bradycardia, or cardiac arrhythmias - Pallor, sweating, hypotension, and syncope - Cardiac arrest is possible. - Respiratory failure - Cardiac arrest. - Delayed healing, necrosis, and ulceration - Local pain that increases in intensity - Anaesthetized puncture wound with hypersensitivity to the surrounding area. - One or more puncture wounds, with an inflamed and sometimes cyanotic zone. - Area that is pale and swollen, with pitting oedema surrounding the cyanotic zone Pricked by a small fish - Insufficient skin protection - Foreign body reaction, chronic localized - Improper behaviour inflammation, edema, necrosis, and - Animal maybe not seen severe disability - Casualty distressed, he may fall into a delirious state. - Malaise, nausea, vomiting, and sweating - Respiratory distress may develop - Cardiovascular shock state may supervene and lead to death - Bite that results in minimal pain for the first 5-10 minutes, and then the bitten area gets numb. This condition spread to the rest of the limb. There may be some bleeding - Nausea, vomiting, and difficulty swallowing. - Double vision, blurred vision, fixed - Insufficient skin protection dilated pupil Bitten by octopus - Improper behaviour (Blue ringed) - Numbness or loss of feeling around the - Animal not seen lips and mouth. After approximately 10 minutes, the victim may have general weakness, difficulty breathing, and paralysis. - Respiratory failure may occur, which may lead to unconsciousness, cardiac arrest, and death. Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 18 of 336  Hyperlink Tables of contents Symptoms linked to diving accidents. (continuation) Symptoms Possible accident Possible causes - Wound ragged with massive bleeding. - Casualty sweaty (cold and clammy) - Insufficient skin protection with a rapid pulse, hypotension - Improper behaviour - Syncope may happen. Bitten by moray eel - Secondary infection in the area is - Animal not seen common. - Immediate pain increasing over 1 to 2 hours and easing after 6 to 10 hours - Swollen and pale area, with a bluish rim, spread around the wound after one or two hours. - Pain may be constant, pain pulsating, or lancinating - Possibility of massive bleeding - Spine integument may be visible - Anorexia, nausea, vomiting, diarrhea, salivation with frequent urination. - Improper behaviour Stingray spine - Muscular cramps, tremors, tonic - Animal not seen paralysis with fever, and sweating. - Difficulty in breathing, cough, and pain on inspiration - Fainting, palpitation, hypotension, cardiac irregularities, and ischemia - Confusion, or delirium - Recurrence of symptoms with aggravation of the pain and secondary infection with necrosis and ulceration within days or weeks - Fatalities are possible - Injuries are from a single bite with no deep cuts to tissue loss, limbs ripped off and death due to the massive bleeding and traumas - Associated with the wounds there may be the following symptoms: Emotional shock bruising and rubbings Massive hemorrhages Foreign objects in the wounds Bitten or amputated by big - Improper behavioural (teeth) predator - Animal not seen fractures Internal organs may be injured Internal hemorrhages Hypovolemic shock Cardiogenic shock Vasodilatation shock Septic shock Death may occur quickly, depending on the hemorrhages and traumas… Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 19 of 336  Hyperlink Tables of contents Page left intentionally blank Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 20 of 336  Hyperlink Tables of contents Part B - Elements of anatomy and physiology - Cell (page 22) - Skeletal system (page 26) - Muscular system (page 30) - Skin (page 35) - Nervous system (page 37) - Circulatory and respiratory systems (page 44) - Digestive and urinary systems (page 57) Note: This part gives a quick overview of some of the main systems that compose the human body and may be involved in several types of accidents or diseases. These systems are all interconnected and work in symbiosis. For example, the digestive system that is fundamental to feed the cells that compose the body is vascularized, and its activity is controlled by the sympathetic nervous system. It is maintained in position and partially protected by the skeletal, and activated by the action of muscles. These organs need oxygen, which the respiratory system provides. They are isolated from the external by the skin, which is also innervated and vascularized. Also, blood cells are generated in the long bones, etc.… As a result, it isn't easy to give an order of description, and the one used in this chapter corresponds to those commonly found in medical books. Note that auditory organs are also involved in equilibrium and space reference functions of the body. However, they are not described here, but in the next chapter, with the accidents in which they are involved. It is also the case of organs that have only one function. These descriptions can be used as complementary references to comprehend the complex processes triggered in an accident or a disease. Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 21 of 336  Hyperlink Tables of contents Cells Description The human body is composed of several hundred different types of cells of various shapes and functions. Despite this great diversity, common characteristics are found. Cells are formed of an internal substance called cytoplasm and an external membrane. The internal parts of the cell also comprise the nucleus and several organs described below. Lysosome Cytoplasm Glucose + protein Mitochondria + lipids + Oxygen Golgi apparatus Centriole Nucleoplasm Nucleus membrane CO2, urea, uric acid, etc. nucleolus Proteins Horm on Ribosome es En zy m Endoplasmic reticulum es The membrane is a soft, half porous unit of 50 to 100 angstroms (1 angstrom = 1 mm/10000), composed of a layer of lipids between two layers of proteins. It comprises pores of 6 to 8 angstroms. The membrane controls the cell’s exchanges with the external that occurs either through the membrane or through the pores, using the principles of osmosis, oncotic pressure, ionic exchanges, and hydrostatic pressures. Note the following: ○ Osmosis is a process of liquids movement through a semi-permeable membrane from a region of lower solute concentration to higher solute concentration to equalize the solute concentrations of the two sides. ○ The oncotic pressure is the osmotic process across the venules and capillaries. This pressure is due to the difference in protein concentration between plasma and interstitial fluid. It counteracts capillary and venule hydrostatic forces in determining net fluid flux across the blood vessels' inner cellular lining (endothelium). ○ Ion-exchange is a chemical reaction between two substances, each composed of electrically charged atoms or molecules. The positively charged ions are called cations, and the negatively charged ions are called anions. ○ Hydrostatic pressure is the pressure exerted by a fluid. As an example, 1 bar equals a column of 10 m of seawater. The cytoplasm is a liquid medium containing dissolved substances (proteins, glucose, some lipids, ions), and the following elements: ○ The “Endoplasmic reticulum” a continuous membrane system that forms a series of flattened sacs that serve multiple functions such as the synthesis, folding, modification, and transport of proteins. ○ Ribosome particles are sites of protein synthesis. They can be free particles or be attached to the membranes of the endoplasmic reticulum. ○ The Golgi apparatus or Golgi complex is involved in the processing and packaging of the macromolecules like proteins and lipids that are synthesized by the cell. Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 22 of 336  Hyperlink Tables of contents ○ Mitochondria are membrane-bound cell organelles (mitochondrion, singular) that generate most of the chemical energy needed to power the cell's biochemical reactions. Chemical energy produced by the mitochondria is stored in a small molecule called adenosine triphosphate. Mitochondria contain their own small chromosomes. Generally, mitochondria, and therefore mitochondrial DNA, are inherited only from the mother. ○ A Lysosome is a membrane-bound cell organelle that contains digestive enzymes that break down excess or worn-out cell parts. They may be used to destroy invading viruses and bacteria. ○ Centrioles are two cylindrical, rod-shaped, microtubular structures near the nucleus that are involved in the cell division. The nucleus is made up of a liquid medium called “nucleoplasm”, separated from the cytoplasm by the nucleus membrane. One small spherical body called nucleolus is present in the nucleoplasm. Note that sometimes there are several nucleoli (plural of nucleolus). A granulous substance called chromatin is also found in the Nucleoplasm. ○ Nucleoplasm main function is to store “deoxyribonucleic acid (DNA)” and facilitate an isolated environment where controlled transcription and gene regulation is enabled. ○ Deoxyribonucleic acid (DNA) is a molecule carrying genetic instructions for the development, functioning, growth and reproduction of all known organisms and many viruses. ○ Chromatin is a combination of DNA and protein whose primary function is packaging long DNA molecules into more compact, denser structures. That prevents the strands from becoming tangled and reinforces the DNA during cell division. ○ The nucleolus is producing and assembling the ribosomes. A ribosome is a complex molecular assembly that produce proteins from amino acids during the process called protein synthesis or translation, which is the primary function of living cells. Following assembly, ribosomes are transported to the cell cytoplasm, where they serve as protein synthesis sites. Cell process Cells behave like small factories: They use fuel and raw materials for given jobs and export or store the products of their activity. They also reject waste and need energy for their activities, which is produced by using fuel and an oxidizer. These activities are regulated, monitored, and directed by their nucleus. The cell draws the food and the oxidizers it needs from the extracellular environment. These different elements enter the cell in three ways: Passive transport or diffusion, without energy consumption: The extracellular elements enter the cell through the pores. The ease of penetration depends on the size of the pores, which are 8 angstroms, and the fact that they have a positive electrical charge. As a result, substances with a negative electrical charge or no electrical charge and which size is smaller than 8 angstroms can easily pass through the pores, while substances with a positive electrical charge and a size larger than to 8 angstroms cannot. Active transport with cellular work and, therefore, energy consumption. Extracellular fluids that are fat-soluble can enter the cell by passing through the membrane, regardless of the size of the pores. It is the case with fatty acids, oxygen, and carbon dioxide. On the opposite, water is stopped by the lipid layer. Note that some non-fat-soluble substances, such as carbohydrates, can take the same path with the help of a lipoprotein molecule, which combines with sugar to constitute a liposoluble compound that can cross the cell membrane. Also, there are cases where the cell forces certain substances to circulate at the opposite of osmosis law. It is the case for sodium and potassium ions, where sodium concentration is low in the cell, and the potassium concentration high, where it is the opposite outside the cell. Therefore, the cell continually expels sodium from a weakly concentrated medium (the cell) to a highly concentrated medium (the extracellular medium). It is said that this means of transfer consumes energy. Note that active transportation mechanisms are still under investigation. Cytoplasmic incorporation or “endocytosis”. Endocytosis is a mechanism of cellular absorption by which the cell gradually incorporates the particle to be absorbed. By deforming the cell membrane envelops the particle, which is then incorporated into the cytoplasm. The particle is then subjected to the action of diastases or digestive enzymes of the cell. Note that the “endocytosis” process is called “pinocytosis” for food molecules and “phagocytosis” for bacteria or biological debris by white blood cells. Cell digestion consists in separating the complex organic elements drawn into the cell to simple organic elements. Diastases or enzymes are biochemical protein substances, which have the property of making possible certain specific biochemical reactions, allowing to break-down complex molecules into simpler elements. There are nearly 2000 different kinds of enzymes that only act on a certain type of biochemical reaction. They are not modified by the chemical reaction which they activate and cannot modify it. Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 23 of 336  Hyperlink Tables of contents In addition, the enzymes produced by the cell are accumulated and packaged in the “Lysosomes” to separate them from other cellular elements (see in the previous point). The digestion, therefore, occurs by attaching one or more Lysosomes to the “endocytosis vacuole”. The lysosomes release their enzymes inside the vacuole, which allows for the degradation of complex food molecules into simple organic elements. Unusable residues remain in the vacuole, which evacuates them outside the cell. Note that the digestion described above occurs at the level of specialized tissues (digestive tract) and within any cell. It always involves enzymes that are synthesized by the cell (role of the plasma reticulum), and then finished and packaged in the “Golgi apparatus”, to be finally stored in the lysosomes. They can either be excreted outside the cell (glandular cells) or stored in lysosomes inside the cell to digest the food contents of endocytosis vacuoles. Food molecule Molecular liaison Enzyme 2 - The enzyme links to the food molecule and cuts the molecular liaisons. 3 - The enzyme abandons 1 - The food molecule is the two more simple reached by the dedicated molecules resulting specific enzyme. from the process. Cells need energy for their various activities. The interaction of fuel and oxidizer provides this energy: The oxidizer is oxygen, for the majority of the reactions which occur aerobically. Fuel is food elements or nutrients: glucose (carbohydrates), fatty acids (lipids), and amino acids (proteins). Numerous complex biochemical reactions take place to release energy by oxidation of glucose and fatty acids with carbon dioxide rejection. At the end of all these reactions, the released energy is fixed on a transporter called “adenosine triphosphate (ATP)”, containing three phosphate radicals. The last two phosphate radicals are linked to the rest of the molecule by energetic bonds requiring a large amount of energy to build up and releasing a large amount of energy when they break. This is how ATP transforms into “adenosine diphosphate (ADP)” when releasing energy, and vice versa, depending on the reaction: ATP = ADP + P ions + energy. The complex reactions resulting from the breakdown of nutrients, in the presence of oxygen and enzymes, and the release of energy occurs in the “mitochondria” (see the drawing in the previous point). The energy released in this way is used in the mitochondria to convert ADP into ATP. The mitochondria is, therefore, the place of cellular energy reactions and that of storage of the energy produced in the form of ATP. The ATP in the mitochondria is used by the cell according to its needs as follows: Cellular absorption and excretion. Mechanical labour, which is most often a contraction. It may be the contraction of muscle fibrils resulting in muscle contraction. It may be the localized contraction of certain portions of the cytoplasm, such as the white cells of the blood. It may be the asymmetric contraction of the filaments that constitute the vibratile cilia with are provided to the borders of certain cells and whose undulation can be a factor of movement and advancement such as flagellum of the sperm. The synthesis of new products. Synthesis means the manufacture of a more or less complex molecule by assembling simple constituent elements (from the Greek synthesis = put together). Plants synthesize the molecules they need using the energy of sunlight: this is photosynthesis. Animal cells synthesize elements necessary for their life using the energy provided by ATP: this is biosynthesis. ○ The biosynthesis of carbohydrates or sugars takes place from glucose molecules not used for energy. The attachment of several hundred glucose molecules makes it possible to synthesize glycogen, which is stored in the liver. ○ The biosynthesis of fats, also called lipid synthesis, is complex. It starts with “acetyl-coenzyme A”, which comes from the breakdown of glucose. Multiple reactions transform this chemical body into fatty acids, which can then be attached to glycerol to form lipids. ○ It is important to note that sugar is the starting point for the biosynthesis of fats. In the case of overweight, an effective weight loss diet should reduce all forms of sugar. ○ Protein biosynthesis is complex since a protein is a three-dimensional structure comprising an extremely complicated assembly called an amino acid. There are twenty different kinds of amino acids, which assembly one behind the other in a particular number and order constitutes the characteristic sequence of a given protein (primary structure). Also, the assembly of these amino acids in space (secondary structure), and then the more or less complicated twisting of the whole on itself (tertiary structure) defines the protein. Ribonucleic acid (RNA) is a non-protein matrix with specific sequences that determine the code that corresponds to each particular amino acid, so that only the sequence of amino acid programmed can be Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 24 of 336  Hyperlink Tables of contents used. It controls all cell life because it controls the way to protein synthesis. Also, enzymes, which control all cell metabolism, are protein substances synthesized by the cell. The key to protein enzymatic synthesis is the key to all cellular life, in all its forms, at all times. RNA is found in the nucleus and is the replica of another basic nucleic acid called “Deoxyribonucleic acid (DNA)”, which contains all the protein manufacturing codes. DNA transmits the key to making a particular protein to the RNA that exits the nucleus through orifices in the nucleus membrane to attach to the ribosomes that are on the endoplasmic reticulum. This transmission is performed by the “transfer RNA”, which is a short nucleotide RNA chain. As previously indicated previously, the nucleus contains nucleic acids called “deoxyribonucleic acid or DNA” and “ribonucleic acid or RNA”. A nucleic acid is made up of the succession of basic structures called nucleotides, which are made up of the combination of three molecules: A phosphoric acid molecule. A sugar, ribose, or deoxyribose, hence the name given to nucleic acid. A nitrogen base. Nucleotides attach by the alternation of phosphorus and sugar molecules, forming a chain, a ribbon, on which the nitrogenous bases are connected perpendicularly. The nitrogenous bases play the fundamental role, determined by their succession the code of the nucleic acid. DNA is the central library where the memory of cells is stored. It is responsible for hereditary transmission and directs the synthesis of proteins. More than a library, it is a real computer, regulating the cellular life and the transmission of that life. The differences between DNA and RNA can be summarized as follows: DNA contains the carbon sugar molecule called “deoxyribose”, while RNA contains the carbon sugar molecule called “ribose”. The difference between ribose and deoxyribose is that ribose has one more -OH group than deoxyribose, DNA is a double-stranded molecule, while RNA is a single-stranded one. DNA is stable under alkaline conditions, while RNA is not. DNA is responsible for storing and transferring genetic information to make other cells and new organisms, while RNA directly codes for amino acids and acts as a messenger between DNA and the ribosomes to transmit genetic information and make proteins. DNA uses the bases thymine, adenine, cytosine, and guanine; RNA uses uracil, adenine, cytosine, and guanine. Paired nucleobase Single nucleobase Single strand Double strands O O CH2 Uracil CH2 Thymine H H H Cytosine H H H Guanine OH H Adenine OH OH Deoxyribose Ribose DNA RNA Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 25 of 336  Hyperlink Tables of contents Skeletal system Overall description The human skeletal system provides support and protection of the body. In addition, it allows for movements and produces blood cells. It is made of bones, cartilage, tendons, and ligaments of the body. Bones are rigid tissues consisting of cells embedded in an abundant hard intercellular material. The two principal components of this material are collagen and calcium phosphate. Blood vessel Periost Trabecular bone Endosteum Compact bone ○ Trabecular bone, also called spongy bone, is a porous part of bones enclosing numerous large spaces with a spongy appearance. The bone matrix is organized into a three-dimensional latticework of bony processes, called trabeculae, which spaces between are often filled with marrow and blood vessels. ○ The “endosteum” is the layer of vascular connective tissue lining the medullar cavities of bones. ○ Compact bone, also called cortical bone, is the denser material of the skeleton that form the outer shell of most bones in the body. ○ The “periost” is the thick fibrous two-layered membrane covering the surface of bones. Cartilage is an elastic smooth tissue, that covers and protects the ends of long bones at the joints and nerves. It is also a structural component of the rib cage, the ear, the nose, the bronchial tubes, the inter-vertebral discs, etc. Note that sharks have their skeletal exclusively made of cartilage. Tendons are tissues that attach muscles to bones and transmits them the mechanical force of muscle contractions. They are made of connective tissues firmly connected to the muscle fibres at one end and the bone at their other end. Ligaments are bands of tough elastic tissue that connect bones, give joints support, and limit their movement. They are present around knees, ankles, elbows, shoulders, and other joints. Muscle Tendon Bone (femur) Patella Cartilage Fat Ligament Bone (fibula) Bone (tibia) Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 26 of 336  Hyperlink Tables of contents An adult’s skeleton contains 206 bones, which 6 of them are those of the ear. It represent approximately 20% of the body weight. Males have a higher bone mass than females, which skeletons are provided with a broader pelvis to accommodate pregnancy and childbirth. Also, children’s skeletons have more bones because some of them fuse with age. Frontal bone Temporal bone Skull Maxilla Mandible clavicle Cervical vertebrae Scapula Sternum Coastal cartilage Rib cage Rib Humerus Ilium Vertebral column Radius Sacrum Coccyx Ulna Pelvic girdle Carpal bones Metacarpal bones Ischium Femur Patella Fibula Tibia Calcaneus Tarsal bones Phalanges Metatarsal bones The bones that constitute the skeleton are classified according to their shapes: Long bones are those where the length predominate on width and thickness (example: Femur). Short bones are those where the 3 dimensions are nearly equal (example: Carpal bones). Flat bones are those with thickness inferior to the other dimensions (example: frontal bone of the skull). Irregular bones have complex shapes that cannot be classified into the categories above (example: vertebras). Sesamoid bones are embedded within a tendon or a muscle (example: Patella). The skeleton is divided into two 2 groups: The axial skeleton, and the appendicular skeleton. 1. The axial skeleton forms the central axis of the skeletal system and provide posture, balance, and stability. It is composed of : ○ The skull, which includes the bones of the cranium, face, and ears (auditory ossicles). ○ The hyoid bone, which is the U-shaped bone or complex of bones located in the neck between the chin and larynx. Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 27 of 336  Hyperlink Tables of contents ○The vertebral column, which is composed of the vertebras. ○The thoracic cage, which is composed of the ribs and the sternum (breastbone). 1. The appendicular skeleton is composed of body limbs and structures that attach limbs to the axial skeleton. the primary function of the appendicular skeleton is for bodily movement, it also provides protection for organs of the digestive system, excretory system, and reproductive system. It is composed of: ○The pectoral girdle, which is composed of the clavicle and scapula. ○The upper limbs, which are the clavicle, scapula, humerus, radius, ulna and hand bones. ○The pelvic girdle, which is made of three fused bones: the “ischium”, the “ilium”, and the “pubis”. ○The lower limbs, which are the bones of the legs and feet. Articulations An articulation, or joint, is where two bones come together. They are classified into immovable, slightly movable, and freely movable joints. Immovable joints, also called synarthroses, include skull sutures, the articulations between the teeth and the mandible, and the joint found between the first pair of ribs and the sternum. These bones come in very close contact and are separated only by a thin layer of fibrous connective tissue. Slightly movable joints are also called amphiarthroses (singular form is amphiarthrosis). This type of joint is made of bones connected by hyaline cartilage or fibrocartilage. It is that case of ribs, which are connected to the sternum , the symphysis pubis, and the joints between the vertebrae and the intervertebral disks. Freely movable joints are also called diarthroses (singular form is diarthrosis). They have the ends of opposing bones covered with hyaline cartilage, and they are separated by a space called the joint cavity. The components of the joints are enclosed in a dense fibrous membrane. The outer layer of the capsule consists of the ligaments that hold the bones together (see the drawing of the shoulder below). The inner layer is the synovial membrane that secretes synovial fluid into the joint cavity for lubrication. Because all of these joints have a synovial membrane, they are sometimes called synovial joints. Synovial fluid in joint cavity Synovial membrane Bone Fibrous membrane Articular cartilage Clavicle Acromioclavicular ligament Trapezoid ligament Conoid ligament Coracoacromial ligament Coracohumeral ligament Transverse Humeral Ligament Humerus Glenohumeral ligaments Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 28 of 336  Hyperlink Tables of contents The vascularization of freely movable joints is very rich and highly organized: Some tissues are highly vascular with a high density of vessels, whilst other tissues are avascular. Vascularization comes from arterial and venous periarticular circles, with some arteries entering the bone a little bit outside the capsule and others being part of the ligaments and the capsule. Artery Synovial joint membrane Fibrous membrane The joint capsule and ligaments of freely movable joints are also richly innervated: ○ Fibrous ligaments have a rich nerve plexus and various specialized and unspecialized nerve endings, most of which are somatic in origin. ○ The synovial membrane contains a more delicate nerve network and various nerve endings, most of which are autonomic in origin. But a substantial number of somatic nerves enter the synovial membrane, some of which terminate in nerve loops, globular endings, or simple unspecialized endings. The joints' nerves also supply the motor muscles connected to the joint and the skin covering the insertion of these muscles. These nerves participate in the reflex regulation of movements and postures. Joints are subjected to varied stresses, which are essentially pulling, twisting, or pressing: The pressures are significant at the level of the spine and the lower limbs. Poor pressure distribution leads to wear and tear of the cartilage and then to bone condensation. Tractions tend to move the joint surfaces away. The capsule, ligaments, periarticular muscles, and intra-articular pressure, which is slightly negative, oppose to this dislocation. Note that the fact that freely movable joints are highly vascularized and innervated may impact them in an inappropriate decompression process. Also, professional or sports microtraumas can lead to lesions responsible for osteoarthritis. Blood making Almost 1 percent of the body’s red cells are generated each day. The rate of blood cell formation varies depending on the individual. A typical production might average 200 billion red cells, 10 billion white cells, and 400 billion platelets per day for an adult. Blood cells are made in the bone marrow that produces: All of the red blood cells. 60 - 70 percent of the white cells. All of the platelets, which are formed from bits of the cytoplasm of the giant cells (megakaryocytes) of the bone marrow The lymphatic tissues, particularly the thymus, the spleen, and the lymph nodes, produce the lymphocytes (comprising 20 - 30 percent of the white cells). The reticuloendothelial tissues of the spleen, liver, lymph nodes, and other organs produce the monocytes (4 - 8 percent of the white cells). Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 29 of 336  Hyperlink Tables of contents Muscular system The muscles allow for moving the body, and create work and heat. They can be classified as follows: Skeletal muscles are streaked muscles that can contract under the influence of the will. They act on the skeletal system. Smooth muscles are unstreaked muscles that escape the influence of the will. They are localized in the viscera, vessels, and skin. Mixed muscles are striated muscles that are independent of the influence of the will. As an example, the muscles of the heart. Skeletal muscles The skeletal muscles represent approximately 40% of the body's weight. Note that passed 25 years, the muscle mass decreases progressively and continuously. This reduction is a function of physical activity. Skeletal muscles are generally composed of a thick body that is contractile and of two narrower white and resistant extremities called tendons. Depending on their shape, they can be: Monogastric muscles, which are shaped like a belly. Polygastric muscles, having more than two bellies. These can be successive (digastric muscles) or juxtaposed (multifidus muscles). Long muscles have their length clearly greater than their thickness and width. They are predominant in limbs. Flat muscle have predominant length and width. Short muscles are reduced in all their dimensions. Annular or circular muscles surround orifices. Example: the sphincter muscles. Square, pyramidal muscles are similar to the homonymous geometric figure. Tendon Contractile part Tendon Multifidus muscle Monogastric muscle Digastric muscles Muscles attach to various surfaces such as bones, cartilages, dermis (skin muscles), mucous membranes (tongue), fascias, fibrous arches. This attachment can be done either by fleshy fibres, tendons, or broad fibrous laminas called aponeurosis. The morphological and mechanical unit of the muscle is the “muscle fibre”, which is made of parallel myofibrils, striated transversely and enveloped by a connective membrane called “sarcolemma”. This envelope contains several peripheral nuclei, and the “sarcoplasm” containing a red pigment called “myoglobin”. Muscle fibres are separated from each other by delicate, vascularized connective tissues called “endomysium”. Also, several fibres are grouped in bundles surrounded by a conjunctive lamina called “perimysium”, and the entire muscle is covered with a dense fibrous tissue called “epimysium”. Tendons and aponeurosis are made up of bulky collagenous fibres organized in the same direction. There is no continuity between the collagenous fibres and the myofibrils because the sarcolemma separates them. The fibers group together in bundles separated by longitudinal planes of loose connective tissue containing the vessels. Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 30 of 336  Hyperlink Tables of contents This connective tissue is called “endotendineum” around primary bundles, “peritendon” around secondary bundles, and “epitendineum” around the tendon. Note that tendons attach to the bone's periost and penetrate the bone tissue (perforating fibers), which explains bone tearing in some lesions. In the elderly, the tendon may ossify over a certain length. The tendon sometimes presents fibrous expansions constituting secondary attachments. Myofibril Sarcolemma Myocyte Muscle bundle Endomysium Nerve Vein & artery Epimysium Perimysium Muscle bundles can: Have the same parallel direction as the tendon bundles (flat muscles) Converge towards the end of the tendons (spindled muscles) Attach to the lateral side of a tendon (unipennate muscles) Attach to both sides of a tendon (bipennate muscles) Attach to the sides of the subdivisions of a tendon (multipennate muscles) Flat muscles Spindled muscles Unipennate muscles Bipennate muscles Multipennate muscles Elements annex of the muscle: Muscle fascia is a tissue that surrounds muscles. It is located either under the skin (superficial fascia) or in contact with the muscles (deep fascia). Note that tearing of the fascia promotes muscle herniation through the fascia breach. The inter-muscular septum is a connective septum separating muscle groups. Interosseous membranes are the septa stretched between bones. The synovial bursa is a membranous bag filled with synovia that promotes the sliding of a muscle against a bone or another muscle. Vinculum and mesotendon are connective formations that are independent or in continuity with each other, and in this case, confused. The vinculum is a formation uniting the tendon with the underlying bone. The Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 31 of 336  Hyperlink Tables of contents mesotendon unites the tendon with the synovial sheath and contains vessels and nerves for the tendon. The muscular trochlea is a fibrous or fibro-cartilaginous ring serving as a reflection pulley for a tendon. Tendons retinaculum are large fibrous lamina holding the tendons. They are surrounded by their synovial sheaths that slide under a retinaculum, stretched between two bones. Numerous arteries vascularize the skeletal muscles. They come from the neighboring arterial trunks, and muscles with the same function are often vascularized by arteries originating from the same trunk. The main artery entry point is often constant. This penetration can be done at the same point as the nerve (polarized muscle) or at a different point (non-polarized muscle). Arteries are divided into multiple capillary branches those whose direction is parallel to the muscle fibers are from these branches. Note that the veins are provided with numerous valves. Also, the belly part of the muscle is more richly vascularized than the tendon. Note that a hypovascularized muscle gets tired very quickly and shows disorders such as cramps. Many muscles have multi-segment innervation, which receives neuro fibers from several spinal nerves. Muscles with a similar function are innervated by the same nerve. Motor innervation is provided by myelinated fibers. Each neuro fibres branches at its distal end, and each branch terminates at a muscle fibres through the motor plate (see the drawing below). The number of muscle fibers per motor unit is inversely proportional to the precision of movements. Endoneurium Myelin sheath Axon Motor plate Muscle fibres Sensory innervation is provided by myelinated fibers whose receptors are the neuromuscular spindles. It informs the nerve centres on the degree of tension and stretching of the muscle. Vasomotor innervation is provided by sympathetic unmyelinated fibers intended for muscle vessels. The tendon corpuscles are located at the musculotendinous junction. They are the starting point for provoked tendon reflexes. Note that the destruction of the nerve makes the muscle atrophic and flaccid. Extrafusal muscle fibers Motor nerve Sensory nerve Intrafusal muscle fibers Capsule A muscle fibre is a modified cell comprising a cytoplasm, the sarcoplasm (from the Greek sarkos = flesh, muscle), a nucleus, and muscle fibrils or myofibrils grouped in parallel bundles, all encased in a cell membrane or sarcolemma. Microscopic examination of the myofibril bundles shows that they are made of a type of protein micro-fibers called “myosin”, and another type which is thinner and is called “actin”. So, the “actin” fibres can slide between the “myosin” fibres. At rest, the spaces between the stripes of actin microfibres correspond to the stripes of myosin fibers, and the spaces between the stripes of myosin microfibres correspond to the stripes of actin microfibres. That explains the tonal stripes that can be observed (light stripe H and streak Z) The passive elasticity and the muscle's active work are related to the possibility of sliding, and therefore of moving away or coming together of the actin fibers within the corridors delimited by the myosin fibers, similarly a cylinder slides in a piston. Muscle elasticity is due to the separation of the ends of the actin fibers, which has the effect of enlarging the white stripe H and separating the two concomitant Z streaks from each other. This results in an elongation of the Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 32 of 336  Hyperlink Tables of contents myofibrils, therefore of the bundle of myofibrils, therefore of the muscle fibre, and therefore of the muscle itself, since all these structures, from the simplest to the most composed, work together. Muscular work is caused by bringing together the ends of the actin fibers, which may even overlap. That reduces and then eliminates the white stripe H, which is finally replaced by a dark stripe (overlap). There is an approach of the associated Z streaks, which can result sin: ○ Muscle tension, if the ends of the muscles do not bring their bony insertions. ○ Contraction if the ends of the muscle bring their bony insertions together. This contraction results in a shortening of the muscle and a movement. Sarcoplasm Streak Z Nucleus Streak Z Stripe H Stripe H Sarcoplasm Fibril Myofibril bundle Since most of the actions of the body require opposite movements (for example, flexion and extension of the forearm), each articulated segment must be provided with two muscles to ensure the movements. The two muscles or the two groups of muscles must work in opposition to obtain opposite movements (see the scheme below): Forearm flexion is achieved by flexing muscles located on the anterior surface of the elbow joint. The extension of the forearm onto the upper arm is achieved by the extensor muscles located on the elbow's posterior surface. Therefore, it is the location of the muscles and especially the position of their bony insertions that determine the result of their action, and it is the coordination of antagonistic muscles that allows for precise and effective movements. Muscle which retraction flexes the forearm Muscle which retraction extends the forearm Smooth muscles Smooth muscle fibers are made up of spindle-shaped cells, non-striated, with a single nucleus, that are smaller than those of striated muscle fibers. They are grouped by a conjunctive-elastic web, forming a more or less thin, elastic, and contractile layer. Note that their contraction is slower than skeletal muscles. These muscles constitute the walls of almost all the hollow organs of the body (Vesicle, bladder, uterus, digestive tract, etc.), and pipes (vessels, bronchi, ureter, glandular ducts, etc.). These muscles also constitute the smooth sphincters controlling the emptying of many organs (bladder, rectum). Diving & ROV specialists - Surface-supplied diving handbook MT92 - Book #1 - Page 33 of 336  Hyperlink Tables of contents Unlike striated fibers, smooth fibers seldom constitute muscle spindles with separate insertion points, except for the small muscles attached to the hairs (muscles that make the hairs crinkle). More numerous than skeletal muscles, smooth muscles are classified according to their shape: Flat smooth muscles. For example, the dartos muscle. Annular smooth muscles. For example, the constrictor muscle of the iris. Tubular smooth muscles. For example, the muscular tunic of the intestine. Vascular smooth muscles. Smooth muscle tissues are provided with a rudimentary intrinsic nervous system made up of plexuses of nerve fibers and nerve ganglia, all belonging to the sympathetic system. It provides the smooth muscle with a certain autonomy, such as a muscle tone independent of innervation coming from the outside and the possibility of contracting in the absence of external nerve stimulation. These automatic contractions account for certain peristalsis (radially symmetrical contractions and relaxations of muscles that propagate in a wave down a tube such as the intestine) made possible by the intrinsic nervous system's coordinating action. Also, there is no degeneration when the external nerves are severed. However, while it can retain some of its properties in the absence of stimulation, the smooth muscle tissue is not really physiologically isolated and left on its own as its activity is controlled by the vegetative nervous system, which can accelerate, slow down, facilitate, or inhibit its activity. This vegetative system is made up of two antagonistic systems, more described in the chapter “Nervous system”, called “sympathetic system” and “parasympathetic system”. Every smooth muscle tissue receives fibres from both systems. However, their terminations are different from those of striated fibers because there is no motor plate. Therefore, there is no depolarizing wave passing from the nerve to the muscle via a chemical mediator. Instead, the chemical mediator is released at the end of the nerve fibre and diffuses into the smooth tissue and changes its state (relaxation or contraction). This diffusion, together with the lack of myofibrils, explains the slowness of the smooth muscle contraction and the length of its recovery time. The mediators consist of: Adrenaline for the terminal fibers of the sympathetic system, which prepares the body for stressful or emergencies. Acetylcholine for the terminal fibers of the parasympathetic system, which regulates body processes during ordinary situations. Smooth muscles are poorly vascularized. Some are even avascular. and feed by imbibition. Smooth fibre (longitudinal cut) Nucleus