Disaster Surgery PDF Chapter 29

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ve Bailey & Love Bailey & Love Bailey & Love 29Love ve Bailey & Love Bailey & Love Bailey & Chapter Disaster surgery Learning objectives To recognise and understand: The role and limitations of field hospitals in disaster The common features of various disasters The features of conditions peculiar to disaster situations The principles behind the organisation of the relief effort and their treatment and of triage in treatment and evacuation INTRODUCTION Natural disasters provide a constant reminder of the power and capricious nature of our planet. The depletion of the ozone layer and global warming mean that the future may hold in store calamitous events with even greater magni- tude than those experienced before. National conflicts and ideological differences have not lessened and the resultant ‘unnatural disasters’ have the potential to rival the natural ones in enormity (see Chapter 30). Disasters by their very nature are unpredictable and no two are alike. Nevertheless, there are numerous common elements and it has been shown that countries that invest in disaster preparedness are better equipped to cope with such catastrophes. Recent wars and disasters have highlighted the increasingly crucial role of sur- Figure 29.1 Damage to emergency medical services. geons in these scenarios. COMMON FEATURES OF MAJOR Summary box 29.1 DISASTERS Common features of major disasters Any event that results in the loss of human life is disastrous, Massive casualties but most accidents, such as aeroplane and train crashes, Damage to infrastructure are limited in the number of people involved. Conversely, A large number of people requiring shelter natural disasters, such as earthquakes and tsunamis, leave Panic and uncertainty among the population in their wake massive destruction over large areas that can Limited access to the area transcend national boundaries. All the apparatus of a soci- Breakdown of communication ety that responds to such disasters (the civil administration, emergency services, fire brigades and hospitals) may itself be involved and unable to respond (Figure 29.1). Large num- bers of people may require immediate shelter, clean water and FACTORS INFLUENCING RELIEF food, in addition to any medical needs. EFFORTS AND PROVISION OF A breakdown of communication is inevitable and can be accompanied by widespread panic and a disruption of civil MEDICAL AID order. Access to the disaster area may be limited because of Good communication is critical for the authorities to respond the destruction of bridges, affecting road and rail links. quickly to a disaster. Wireless technology and satellite imag- 04_29-B&L27_Pt4_Ch29.indd 409 25/10/2017 08:23  PART 4 | TRAUMA 410 CHAPTER 29  Disaster surgery Summary box 29.2 Factors influencing rescue and relief efforts Status of communications Location, whether rural or urban Accessibility of the location Time-frame in which disaster occurs Economic state of development of the area The time-frame in which a disaster occurs also impacts on the relief efforts. Earthquakes can unleash havoc in sec- onds but floods and hurricanes may continue for several days. Another important factor is the state of resources of the coun- try; disasters in poorer countries can seldom be managed with- out significant outside assistance. Figure 29.2 Satellite image showing destruction of a bridge as a SEQUENCE OF RELIEF EFFORTS result of flooding. AFTER A DISASTER ery have revolutionised the way in which real-time informa- Establishing a chain of command tion can be obtained (Figure 29.2). Nonetheless, there is an Many countries have dedicated organisations that deal with inevitable lag period between the occurrence of the disaster disasters. In others, an administrative hierarchy is established and the response from the establishment. to coordinate the efforts of the teams participating in relief The location of the disaster area has a bearing on relief efforts (Figure 29.3). efforts. In large cities emergency and medical services are better developed. However, these areas are densely populated and may have limited access by road and air. Disasters in Damage assessment remote areas can be particularly difficult to manage because The first objective in disaster management is an assessment relief efforts are hampered by geographical isolation and the of the damage and the number of casualties. All sources of lack of infrastructure. information must be employed. The 24-hour news services Chief of operations Medical services Management Triage leader Evacuation Communications leader Immediate Triage teams Ambulance treatment Urgent treatment Helicopter Security Minor treatment Transport Morgue Search/ rescue Coordination Communications Figure 29.3 Organisation chart for disaster management. 04_29-B&L27_Pt4_Ch29.indd 410 25/10/2017 08:23  PART 4 | TRAUMA Sequence of relief efforts after a disaster 411 are frequently the first on the scene and can be an important types of injuries encountered by rescue workers depends on source of information. the delay between the onset of the disaster and their arrival. Patients with head injuries and abdominal and thoracic trauma will either have been treated or have succumbed to Mobilising resources their injuries within 48–72 hours of a disaster. After the first The next step is mobilisation of human and material resources week, the only casualties requiring treatment are those with appropriate to the extent of the disaster. Although all modes complex limb trauma and infected wounds (Figure 29.5). of transport need to be considered, helicopters provide the quickest access for the first responders (Figure 29.4). The teams who make up the initial response must include expe- Coordination with relief agencies rienced staff who can assess the situation and who have the A laudable aspect of globalisation is the outpouring of help authority to take immediate decisions. from governments and non-governmental organisations (NGOs) in response to a disaster. Some, like Rescue and Preparedness in Disasters (RAPID), deal with search and res- Rescue operation cue whereas others, like the International Committee of the Early coordination of the rescue effort allows optimal use Red Cross (ICRC) and Oxfam, provide general disaster-re- of resources. The first priority is to prevent further damage lated relief (Figure 29.6). The various United Nations (UN) from occurring, both to people and to the infrastructure. The agencies deal with medical care, food provision and refugees. Coordinating the efforts of these organisations is essential for optimal results, as medical aid in isolation is inadequate with- out the simultaneous provision of safe drinking water, food, clothing and shelter. Summary box 29.3 Sequence of the relief effort in major disasters Establish chain of command Set up lines of communication Carry out damage assessment Mobilise resources Initiate rescue operation Triage casualties Start emergency treatment Arrange evacuation Start definitive management Figure 29.4 Heli-evacuation. 100 90 80 55 70 65 Percentage 60 Limb injuries 85 95 95 100 50 Facial trauma 40 15 Abdominal and 30 chest trauma 15 20 20 Head injury 10 10 10 10 5 5 5 5 0 12 hours 24 hours 48 hours 1 week 2 weeks 1 month Figure 29.5 Time-line showing the type of injuries encountered at different times in a disaster. 04_29-B&L27_Pt4_Ch29.indd 411 25/10/2017 08:23  PART 4 | TRAUMA 412 CHAPTER 29  Disaster surgery is a daunting prospect. Triage should be undertaken by some- one senior, who has the experience and authority to make these critical decisions. To keep pace with the changing clini- cal picture of an injured person, triage needs to be undertaken in the field, before evacuation and at the hospital. Triage areas For efficient triage the injured need to be brought together into any undamaged structures that can shelter a large num- ber of wounded. A good water supply, lighting and ease of access are useful. Separate areas should be reserved for patient holding, emergency treatment and decontamination (in the event of discharge of hazardous materials). Figure 29.6 Oxfam and the International Committee of the Red Practical triage Cross provide generalised relief. Emergency life-saving measures should proceed alongside tri- age and can actually help the decision-making process. The assessment and restoration of airway, breathing and circula- tion are critical and are discussed in Chapter 23. Vital signs Dealing with the media and a general physical examination should be combined with Disasters act like a magnet for the media which, in today’s a brief history taken by a paramedic or by a volunteer worker world of 24-hour news coverage, plays an important part in if one is available. shaping public opinion. It is essential to establish a working relationship between the media and the rescue teams. With Documentation for triage careful handling the media can become a powerful ally and Accurate documentation is an inseparable part of triage and play a constructive role in identifying problems, galvanising should include basic patient data, vital signs with timing, aid and keeping the public informed. brief details of injuries (preferably on a diagram) and treat- ment given. A system of colour-coded tags attached to the patient’s wrist or around the neck should be employed by the Triage emergency medical services. The colour denotes the degree Derived from the French verb ‘trier’, triage means ‘to sort’ of urgency with which a patient requires treatment (Figure and is the cornerstone of the management of mass casualties. 29.7). It aims to identify the patients who will benefit the most by being treated the earliest, ensuring ‘the greatest good for the Triage categories greatest number’. Numerous studies show that only 10–15% All methods of triage use simple criteria based on vital signs. of disaster casualties are serious enough to require hospital- A rapid clinical assessment should be made taking into isation. By sorting out the minor injuries, triage lessens the account the patient’s ability to walk, their mental status and immediate burden on medical facilities. Deciding who receives the presence or absence of ventilation or capillary perfusion. priority when faced with hundreds of seriously injured victims A commonly used four-tier system is presented in Table 29.1. TABLE 29.1 Triage categories. Priority Colour Medical need Clinical status Examples First (I) Red Immediate Critical, but likely to survive if treatment Severe facial trauma, tension pneumothorax, given early profuse external bleeding, haemothorax, flail chest, major intra-abdominal bleed, extradural haematomas Second (II) Yellow Urgent Critical, likely to survive if treatment given Compound fractures, degloving injuries, within hours ruptured abdominal viscus, pelvic fractures, spinal injuries Third (III) Green Non-urgent Stable, likely to survive even if treatment Simple fractures, sprains, minor lacerations is delayed for hours to days Last (0) Black Unsalvageable Not breathing, pulseless, so severely Severe brain damage, very extensive burns, injured that no medical care is likely to major disruption/loss of chest or abdominal help wall structures Triageis the earliest example of clinical risk management. This is done on the basis of need so that resources can be allocated by good prioritisation. The process was first used in 1792 by Baron Dominique Jean Larrey, Surgeon in Chief to Napoleon’s Imperial Guard. The concept of triage emerged from the French Service de Sante so that resources could be used to the optimum – “most for the most”. 04_29-B&L27_Pt4_Ch29.indd 412 25/10/2017 08:23  PART 4 | TRAUMA Sequence of relief efforts after a disaster 413 FRONT BACK FRONT BACK Comments/Information Patient’s Name TRIAGE TAG E RESPIRATIONS PERFUSION MENTAL STATUS E R P M Yes  2 Sec. Can Do PL No  2 Sec. Can’t Do PL , 1 2 3 4 5 DMS-CFCA rev 2/24/2006 Move the Walking Wounded MINOR M No Respirations After Head Tilt MORGUE M SA Respirations - Over 30 IMMEDIATE X 1-800-425-5897 www.mettag.com iv SA im Perfusion - Capillary Refill Over 2 Seconds Mental Status - Unable to Follow Simple Commands IMMEDIATE IMMEDIATE 0 0 0 Otherwise DELAYED ©1996 Disaster Management Systems, Inc. ¥ Pomona, CA I I I (909) 594-9596 ¥ www.TriageTags.com PERSONAL INFORMATION NAME II II II ADDRESS CITY ST ZIP PHONE III III III COMMENTS RELIGIOUS PREF. (a) (a) MOR GUE MOR GUE Pulseless/ Pulseless/ Non-Br ea thing Non-Br ea thing IMMEDIATE IMMEDIATE Life Threatening Life Threatening Injury Injury DELAYED DELAYED Serious Serious Non Life Threatening Non Life Threatening Figure 29.7 Triage tags. (a) Courtesy of TACDA & METTAG products, American Civil Defense Association. (b) Courtesy MINOR MINOR Walking Wounded Walking Wounded of Disaster Management Systems. (b) (b) Evacuation of casualties evacuation can be organised (Figure 29.8). Whether the traditional tented structure or the modular type housed in Decisions regarding the best destination for each patient need containers is employed, the facility must be equipped with to be based on how far it is safe for them to travel and whether radiograph capability, operating rooms, vital signs monitors, the facilities that they need for definitive treatment will be sterilising equipment, a blood bank, ventilators and basic lab- available. A quick retriage is very useful in this situation. The oratory facilities. paramedics accompanying the casualties should be resolved to prevent the ‘second accident’ (damage caused inadvertently by transport and treatment). An adequate supply of essentials Management in the field such as intravenous fluids, dressings, pain medication, and oxygen must be arranged (see Chapter 30). Field hospitals principally function in three main areas (Table 29.2). Field hospitals First aid The decision to deploy field hospitals depends on the loca- Care for patients with minor injuries involves cleaning and tion, the number of casualties and the speed with which dressing wounds, suturing lacerations and splinting simple fractures. Most of these ‘walking wounded’ can be sent away with antibiotics and simple pain relief. Summary box 29.4 DAMAGE CONTROL SURGERY Essentials of casualty evacuation Damage control surgery (DCS) is the concept that only life- Retriage to upgrade priorities amongst the injured and limb-saving surgery be performed in field hospitals to Select appropriate medical facilities for transfer allow safe transfer of a patient to a definitive treating facility. Choose appropriate means of transport This will include ensuring that the airway is secure, haemor- Prevent the ‘second accident’ during transfer rhage is under control and compartments are decompressed Ensure an adequate supply of materials to accompany the in the chest, skull, abdomen and the limbs. Devitalised tissue patient should be removed and any contamination prevented from 04_29-B&L27_Pt4_Ch29.indd 413 25/10/2017 08:23  PART 4 | TRAUMA 414 CHAPTER 29  Disaster surgery (a) (b) (d) (c) Figure 29.8 Field hospitals: (a, b) modular type; (c) tented struc- ture; (d) interior of a tented field hospital. TABLE 29.2 Type of treatment given in field hospitals. Examples Further First aid Suturing cuts and lacerations, splinting simple Review at local hospital fractures Emergency care for life- Endotracheal intubation, tracheotomy, relieving After damage control surgery, transfer patients to threatening injuries tension pneumothorax, stopping external base hospitals once stable haemorrhage, relieving an extradural haematoma, emergency thoracotomy/laparotomy for internal haemorrhage Initial care for non-life- Debridement of contaminated wounds, reduction of Transfer patients to base hospitals for definitive threatening injuries fractures and dislocations, application of external management fixators, vascular repairs developing into infection. DCS is explained in more detail, in the context of early management and other settings, through- Summary box 29.5 out the chapters in the trauma section (see Part 4: Trauma). Principles of damage control surgery Emergency care for immediate life- Do the minimum needed to allow safe transfer to a definitive facility threatening injuries Take actions that prevent deterioration of that patient during There are many patients who may be saved by relatively sim- transfer ple measures, provided that these are taken urgently. Endotra- Secure the airway – may require tracheostomy cheal intubation and tracheotomy may be needed to provide Control bleeding – may require craniotomy, laparotomy, a secure airway. A needle thoracocentesis will relieve a ten- thoracotomy, repair of major limb vessels sion pneumothorax and a chest drain will be needed before a Prevent pressure build up – may require burr holes, chest patient with a significant chest injury is transferred by air. An drain, laparotomy, fasciotomy open pneumothorax should be closed. Damaged major vessels Prevent infection by extensile exposure and removing dead and contaminated tissue to limbs should be repaired if possible. Fasciotomies will be 04_29-B&L27_Pt4_Ch29.indd 414 25/10/2017 08:23  PART 4 | TRAUMA Sequence of relief efforts after a disaster 415 needed for muscle compartments that are swelling from injury After the administration of anaesthesia, the injured area or from reperfusion. Amputation for clearly devitalised limbs is copiously irrigated with normal saline. Lavage using a and gas gangrene should be undertaken at field hospitals as pressurised system is controversial, with concerns over delay will be fatal. tissue trauma and spread of debris (Figure 29.10). The Specific aspects of care are discussed in the relevant chap- wound is palpated and all foreign matter removed. Dirt ters elsewhere in this book. and debris enmeshed in soft tissues can only be removed by excision of those tissues. Open joints should be thor- Initial care for non-life-threatening injuries oughly irrigated and all foreign material removed. Many patients sustain serious injuries that require prolonged Wounds with extensive cavitation should be enlarged care. These include compound limb fractures, degloving inju- longitudinally to gain better access and allow full decom- ries, dislocations of major joints, major facial injuries and com- pression of the underlying muscles. This should be carried plex hand injuries. These patients will need specialised care out under tourniquet. This helps to visualise the damaged requiring transfer to the appropriate facility. Replantations of structures, and allow the surgeon to gain proximal and amputated limbs and other extensive procedures should not distal control of vascular injuries, and to identify severed be attempted in field hospitals as they are time-consuming ends of major nerves and tendons. and divert resources and personnel to the treatment of a few The next step is excision of all dead and devitalised tissue. patients. At this stage the tourniquet is let down to check the vas- cularity of the tissues. Skin excision is kept to a minimum and only the margins of the wound need be trimmed back Debridement to healthy bleeding edges. Excision of devitalised muscle Taken from the French, meaning to ‘unleash or cut open’, should be undertaken generously. Muscle that is pale or debridement plays a crucial part in the management of dark in colour, does not contract on pinching and does trauma. Wounds sustained in disasters are often heavily con- not bleed on cutting must be removed. In patients with taminated, containing foreign bodies and non-viable tissues traumatic amputations, the bone ends are tidied, the skin (Figure 29.9). Debridement reduces the chances of anaer- and muscle edges trimmed to the lowest level possible and obic and necrotising infections and can prevent systemic the wound left open. sepsis. The following principles of debridement apply to all In patients with associated fractures, skeletal stabilisa- contaminated wounds: tion should be obtained before embarking on any repairs. External fixators are invaluable for this and make wound (a) management much easier (Figure 29.11). (b) Figure 29.10 Lavage with normal saline to decontaminate a wound. Figure 29.9 (a, b) Gross contamination typically seen in wounds sustained in disasters. The radiograph shows numerous radiopaque Figure 29.11 External fixators provide skeletal stabilisation and foreign bodies in the soft tissues. allow easy management of the soft tissues. 04_29-B&L27_Pt4_Ch29.indd 415 25/10/2017 08:23  PART 4 | TRAUMA 416 CHAPTER 29  Disaster surgery In the acute setting, only vascular repairs are justified. For (a) lacerated vessels the ends are trimmed and an anastomosis performed. In the case of loss of substance of the vessel wall, a vein patch or reversed vein graft may be employed. Silicone tubing may be used as a temporary bypass (stent) while vascular repair is being carried out in patients with critically compromised distal circulation. Nerves and tendons should not be dissected out nor should any attempt be made at definitive repair in wounds with tissue devitalisation, as this leads to poor results. The (b) key structures should be identified and the edges trimmed and tagged with non-absorbable sutures to facilitate repair during subsequent exploration. Wounds sustained in disasters are heavily contaminated and are not suitable for primary closure. However, blood vessels and exposed joint surfaces need to be covered. This can be achieved by loosely tacking adjoining muscle over the exposed area. The wound is then covered with fluffed gauze and sterile cotton and the extremity splinted with a plaster of Paris slab. For extremity injuries, elevation is Figure 29.12 (a, b) Use of low-pressure vacuum therapy in prepar- critical to reduce oedema. ing a wound for secondary closure. Broad-spectrum antibiotics, such as third-generation cephalosporins, are started prophylactically and contin- ued for 5–7 days. the number of injured that they can handle. The resources The wound is reinspected at 24–48 hours to assess the required for trauma patients are more than the typical case viability of the tissues. Wounds are closed between the mix of a hospital. A rule of thumb is that only half the bed fourth and sixth day if there is no infection. Tension strength of a hospital can be utilised to provide optimum should be avoided and one should not hesitate to use skin trauma care in an emergency situation. grafts to obtain cover. In wounds with gross infection no attempt at closure is made until infection is eradicated. These wounds are Hospital reorganisation re-explored to make sure that there are no residual for- In hospitals receiving mass casualties some reorganisation of eign bodies or devitalised tissue. Tissue should be taken services is unavoidable. This includes transferring patients for microbiological culture. Vacuum-assisted closure (Vac- with non-urgent conditions to other facilities, augmenting Pac) has emerged as a very useful tool for deeply cavitating surgical services, reorganising the specialist rota and redes- wounds. It utilises low-pressure suction to evacuate exu- ignating medical wards as surgical care areas. An appeal for date, promote granulation tissue and reduce the size of the blood donations should be broadcast. wound (Figure 29.12). Once the wounds are free from infection secondary closure can be undertaken. SPECIFIC ISSUES There is no injury that is peculiar to disasters and the whole DEFINITIVE MANAGEMENT spectrum of external injuries from minor cuts, compound The hospitals designated to undertake definitive management fractures and amputations is seen. Internal organ damage should be selected on the basis of the facilities available and is frequent and, unless immediate help is available, this accounts for the majority of early mortality figures. People trapped under fallen buildings may suffer crush injuries and Summary box 29.6 crush syndrome if the duration is prolonged. Crush injuries Principles of debridement and initial wound care and missile injuries cause extensive tissue damage and gross contamination, both favourable conditions for anaerobic and Obtain generous exposure through skin and fascia micro-aerophilic infections. Identify neurovascular bundles Excise devitalised tissue Remove foreign bodies Limb salvage Repair major vessels The Mangled Extremity Severity Score (MESS) and its mod- Obtain skeletal stabilisation with external fixators ifications are useful in deciding about limb salvage. Extensive Only tag tendons and nerves that have been cut tissue loss, neurovascular damage and loss of long fragments of Leave the wound open and delay primary closure bone are traditionally indications for amputation. Currently, Avoid tight dressings wounds of any dimension can be covered with microvascu- Elevate the injured limb lar flaps and distraction osteogenesis and vascularised bone 04_29-B&L27_Pt4_Ch29.indd 416 25/10/2017 08:23  PART 4 | TRAUMA Specific issues 417 can be used to restore bony continuity. If performed in time, soil. It enters the body through a wound and replicates, thriv- vascular repairs can salvage most acutely ischaemic limbs. ing on the anaerobic conditions present in devitalised tissues. Because of these developments the indications for amputation It produces tetanospasmin, an exotoxin that binds to the neu- in trauma have undergone a paradigm shift and the majority romuscular junctions of the central nervous system neurones, of patients who reach a tertiary-care facility within 24 hours rendering them incapable of neurotransmitter release. This are candidates for limb salvage (Figure 29.13). This assumes leads to failure of inhibition of motor reflex responses to sen- that debridement and, if required, vascular repairs have been sory stimulation and generalised contractions of agonist and performed in a field medical facility. A limb is unlikely to antagonist muscles produce tetanic spasms. The median incu- survive if the vascular repair of major limb vessels has been bation period is 7 days, ranging from 4–14 days. delayed for more than 4–6 hours. Early symptoms are painful spasms of the facial muscles resulting in risus sardonicus (Figure 29.15). The spasms Facial injuries spread to involve the respiratory and laryngeal muscula- ture. Spasms of the paravertebral and extensor limb muscu- The management of facial injuries follows the same general lature produce opisthotonus, an arching of the whole body. principles of debridement and delayed closure as already out- Laryngeal muscle spasm leads to apnoea and, if prolonged, to lined. Because of the functional and cosmetic importance of asphyxia and respiratory arrest. The spasms can be brought on facial structures, skin and soft-tissue excisions are kept to a by the slightest of sensory stimulus. minimum. The face has a robust vascularity and a high ability The diagnosis is obvious once it is fully manifest. There to counter infection. Even in patients who present late with are three aspects of management: gross contamination, careful debridement followed by delayed primary closure can lead to good results (Figure 29.14). Prevention. Wounds contaminated with soil can harbour tetanus spores, and active immunisation is indicated by administering 0.5 mL of tetanus toxoid intramuscularly. Tetanus Patients with gross contamination of cavitating wounds This potentially fatal condition, also called ‘lockjaw’, is caused should also receive 250–500 U of human anti-tetanus by Clostridium tetani, a gram-positive spore-forming bacillus globulin (ATG) intramuscularly to provide passive immu- occurring naturally in the intestines of humans and in the nisation and to neutralise the circulating toxin. In full- (a) (b) (c) (d) Figure 29.13 (a–d) Badly traumatised lower limb. Reconstruction has been performed using a microvascular rectus abdominis flap covered with a skin graft. 04_29-B&L27_Pt4_Ch29.indd 417 25/10/2017 08:23  PART 4 | TRAUMA 418 CHAPTER 29  Disaster surgery (a) (b) (c) (d) Figure 29.14 (a–d) Late-presenting facial injury with gross contam- ination. A thorough debridement followed by delayed primary closure has yielded good results. blown clinical tetanus, 3000–10 000 U of ATG should be administered. Wound manipulation should be avoided for 2–3 hours after ATG administration to minimise tetano- spasmin release. Local wound care. This includes a thorough wound debridement to eliminate the anaerobic environment. Intravenous administration of 10–24 × 106 U per day of penicillin G should be continued for 10–14 days. The wound should be closed using the delayed primary or sec- ondary closure techniques. Supportive care for established disease. These patients are nursed in an intensive care unit (ICU) environment, free from strong sensory stimuli. Diazepam is useful in pre- venting the onset of spasms but if these become sustained, the patient is paralysed, intubated and placed on a venti- lator. The patient is then gradually weaned off the ventila- Figure 29.15 Risus sardonicus of ‘lockjaw’ (courtesy of Dr Samira tor under cover of anticonvulsants. The overall mortality Ajmal, FRCS). rate is around 45%, prognosis being determined by the 04_29-B&L27_Pt4_Ch29.indd 418 25/10/2017 08:23  PART 4 | TRAUMA Specific issues 419 (a) Summary box 29.7 Tetanus Caused by Clostridium tetani Spores are present in the soil Thrives in dead or contaminated tissue Produce tetanospasmin an exotoxin Produces spasm of muscles Make sure patients are immunised For heavily contaminated wounds give anti-tetanus globulin incubation period and the time from the first symptom to the first tetanic spasm. In general, shorter intervals indi- cate a poorer prognosis. Necrotising fasciitis Necrotising fasciitisis is a rapidly spreading infection that pro- duces necrosis of the subcutaneous tissues and overlying skin. (b) It is caused by β-haemolytic streptococci and, occasionally, Staphylococcus aureus but may take the form of a polymicro- bial infection associated with other aerobic and anaerobic pathogens, including Bacteroides, Clostridium, Proteus, Pseu- domonas and Klebsiella. It is termed Fournier’s gangrene when it affects the perineal area and Meleney’s gangrene when it involves the abdominal wall. The underlying pathology includes acute inflammatory infiltrate, extensive necrosis, oedema and thrombosis of the microvasculature. The area becomes oedematous, painful and very tender. The skin turns dusky blue and black secondary to the progressive underly- ing thrombosis and necrosis (Figure 29.16). The area may develop bullae and progress to overt cutaneous gangrene. It spreads contiguously but occasionally produces skip lesions that later coalesce. It is accompanied by fever and severe tox- icity. Renal failure may occur as a result of hypovolaemia and (c) cardiovascular collapse caused by septic shock. The rate of progression is dramatic and unless aggressively treated it leads to serious consequences with mortality approaching 70%. The diagnosis is made on clinical grounds. Creatinine kinase levels may show enormous elevation and biopsy of the fascial layers will confirm the diagnosis. Patients should be admitted to the ICU and treated with careful monitoring of volume derangements and cardiac status. Oxygen supplemen- tation is beneficial and endotracheal intubation is required in patients unable to maintain their airway. High-dose penicillin G along with broad-spectrum anti- biotics, such as third-generation cephalosporins and met- Figure 29.16 (a) Necrotising fasciitis at presentation and (b) rapid progression seen after 24 hours. (c) Typical bullae and induration. ronidazole, are given intravenously. The cornerstone of management is surgical excision of the necrotic tissue. The devitalised tissue is removed generously, going beyond the prone to spread beyond the edges of the excised wound. In area of induration. The wound is lightly packed with gauze patients who survive, this results in a large wound, which will and dressed. This process is repeated daily as the necrosis is require skin grafting or flap coverage. Theodor Albrecht Edwin Klebs, 1834–1913, Professor of Bacteriology successively at Prague, Czechoslovakia, Zurich, Switzerland and then the Rush Medical College, Chicago, USA. Jean Alfred Fournier, 1832–1915, syphilologist, the Founder of the Venereal and Dermatological Clinic, Hospital St. Louis, Paris, France. Frank Lamont Meleney, 1889–1963, Professor of Clinical Surgery, Coumbia University, New York, USA. 04_29-B&L27_Pt4_Ch29.indd 419 25/10/2017 08:23  PART 4 | TRAUMA 420 CHAPTER 29  Disaster surgery Summary box 29.8 Necrotising fasciitis Caused by β-haemolytic strep or is polymicrobial Also called Fournier’s or Meleney’s gangrene Progress is rapid and renal failure is an early complication Treat with radical surgical excision repeated every 24 hours Give oxygen and penicillin Recently, the role of hyperbaric oxygen (HBO) has become more established with a reduction in mortality in patients treated with HBO (9–20%) compared with patients Figure 29.17 Typical picture of spreading gas gangrene caused by who did not receive HBO (30–50%). a crush injury. Gas gangrene The diagnosis is made on the basis of history and clinical Gas gangrene is a dreaded consequence of late presenting mis- features: a peripheral blood smear may suggest haemolysis; a sile wounds and crushing injuries. It is a rapidly progressive, Gram stain of the exudate reveals large gram-positive bacilli potentially fatal condition characterised by widespread necro- without neutrophils; and the biochemical profile may show sis of the muscles and soft-tissue destruction. The common metabolic acidosis and renal failure. Radiography can visual- causative organism is Clostridium perfringens, a spore-forming, ise gas in the soft tissues and is particularly useful in patients gram-positive saprophyte that flourishes in anaerobic condi- with chest and abdominal involvement. tions. Other organisms implicated in gas gangrene include C. Patients should be admitted to the ICU and treated bifermentans, C. septicum and C. sporogenes. Non-clostridial aggressively with careful monitoring. High-dose penicillin G gas-producing organisms such as coliforms have also been iso- and clindamycin, along with third-generation cephalospo- lated in 60–85% of cases of gas gangrene. rins, should be given intravenously. Surgical treatment is the C. perfringens produces many exotoxins but their exact same as for necrotising fasciitis (see above). In established gas role is unclear. Alpha-toxin, the most important, is a leci- gangrene with systemic toxicity, amputation of the involved thinase, which destroys red and white blood cells, platelets, extremity is life saving and should not be delayed. No attempt fibroblasts and muscle cells. The phi-toxin produces myocar- is made at closure, amputation stumps are left open and the dial suppression while the kappa-toxin is responsible for the wound is lightly packed with saline-soaked gauze and then destruction of connective tissue and blood vessels. dressed. Devitalised tissue or premature wound closure provides The role of HBO is not as clear as in necrotising fasci- the anaerobic conditions necessary for spore germination. itis, but it is recommended in severe cases if the facilities are The usual incubation period is