Legal Medicine: Asphyxial Deaths PDF

**OUTLINE** I. **Asphyxia** a. Different mechanisms of Asphyxia deaths b. Classic signs of asphyxia c. Different ways in which asphyxia is achieved II. **Compression asphyxia** III. **Smothering** IV. **Choking** V. **Breathing irrespirable gases** a. Carbon monoxide b. Carbon dioxi...

**OUTLINE** I. **Asphyxia** a. Different mechanisms of Asphyxia deaths b. Classic signs of asphyxia c. Different ways in which asphyxia is achieved II. **Compression asphyxia** III. **Smothering** IV. **Choking** V. **Breathing irrespirable gases** a. Carbon monoxide b. Carbon dioxide c. Hydrogen cyanide d. Hydrogen Sulfide e. Sulfur Dioxide VI. **Drowning** g\. Now considered unreliable signs of drowning f. Diatom test g. Accidental, Homicidal, Suicide. +-----------------------+-----------------------+-----------------------+ | **LEGEND** | | | +=======================+=======================+=======================+ | ⭐ | 🖊️ | 📖 | | | | | | Must | Lecture | Book | | | | | | Know | *\[lec\]* | *\[bk\]* | +-----------------------+-----------------------+-----------------------+ ASPHYXIA {#asphyxia.TransOutline} ======== - Violent death is due primarily from the interference with the process of respiration or the condition in which the supply of oxygen to the blood or to the tissues or both has been reduced below normal level. - 🖊️ *So the common denominator here is really anoxia* DIFFERENT MECHANISM OF ASPHYXIAL DEATHS {#different-mechanism-of-asphyxial-deaths.TransSubtopic1} --------------------------------------- ---------------------------------------- **Table 1. Types of Asphyxial deaths** ---------------------------------------- +-----------------------------------+-----------------------------------+ | Anoxic | Failure of arterial blood to be | | | normally saturated with oxygen | | | | | | 🖊️*This might happen if there is | | | an obstruction to the air | | | passages because of smothering, | | | choking, or compression of the | | | chest.* | +===================================+===================================+ | Anemic Anoxic | Decreased capacity of blood to | | | carry oxygen. | | | | | | 🖊️*This might occur in carbon | | | monoxide poisoning or severe | | | hemorrhage where you have severe* | | | | | | *anemia* | +-----------------------------------+-----------------------------------+ | Histoxic Anoxic | Failure of the cellular oxidative | | | process | | | | | | 🖊️ *We have oxygen in the blood, | | | there is no failure there, there | | | is no failure to carry, there is | | | no decreased capacity or | | | incapacity of the blood to carry | | | oxygen but for whatever reason, | | | we cannot utilize the oxygen at | | | the cellular level. A classic | | | example of this would be cases of | | | cyanide poisoning.* | | | | | | Cyanide and alcohol are common | | | agents responsible for histotoxic | | | anoxic death | +-----------------------------------+-----------------------------------+ | Stagnant Anoxic | Failure of circulation | | | | | | 🖊️ *Pulmonary embolism or those | | | with heart failure* | | | | | | Shock, arterial and venous | | | obstruction, vascular spasm, | | | varicose veins, or the use of | | | tourniquet | +-----------------------------------+-----------------------------------+ CLASSIC SIGNS OF ASPHYXIA {#classic-signs-of-asphyxia.TransSubtopic1} ------------------------- 1. Petechial hemorrhages 2. Congestion and edema 3. Engorgement of right heat and great veins 4. Cyanosis - Non-specific - Asphyxia diagnosis **requires other corroborating evidence.** - Especially finding of a cause for mechanical obstruction of respiration - 🖊️If we're thinking anoxic asphyxia, go find whatever obstructed the airways. For instance, they found an object that got lodged in the trachea. That would be your corroborating evidence. - ⭐They are called classic signs because we typically associate them with asphyxia deaths but do note that these are very non-specific. So, finding them alone might not be sufficient to sign off a death as an asphyxial death even if they occur together in the absence of corroborating evidence. - ⭐ (-) Corroborating evidence: COD undetermined - 🖊️ The rule is because these classic signs of asphyxia are so non-specific in the absence of corroborating evidence it might just be why we just sign off the cause of death as undetermined. - 🖊️ But you do find a lot of these signs in certain types of asphyxia deaths like in compression asphyxia. PETECHIAL HEMORRHAGE {#petechial-hemorrhage.TransSub-subtopic2} -------------------- - Small pin-point collections of blood (0.1-2 mm) - Skin - Under the scalp - Scleral or subconjunctival - Under thoracic serous membranes such as the visceral pleura ⭐ **("TARDIEU SPOTS")** or pericardium - When in the brain, often in the white matter - Due to rupture of small venules from acute rise in venous pressure - 🖊️ Which you typically get when you apply pressure to the neck or to the chest preventing it from expanding - May vanish with putrefaction and freshwater immersion. - Very non-specific - Often present in normal post-mortem hypostasis - Found in interlobar fissures and around the hilum in most routine autopsies - May occur with violent coughing or sneezing - ⭐ **Most significant if facial or ocular** - Unless the body was face down or head down - 🖊️This is the exception. You likely would not appreciate the petechial hemorrhages there around the face and the eyes - 🖊️Because if they are concentrated in these regions of the body, then that gives you a clue as to the level of obstruction that caused that acute rise in venous pressure that led to petechial hemorrhages. - 🖊️ So, if you find them around the face and the eye then that is more telling than finding petechial hemorrhages in random areas of the body. A close-up of an eye Description automatically generated Figure 1. Petechial hemorrhages surrounding the eye  Figure 2. Tardieu spots CONGESTION AND EDEMA {#congestion-and-edema.TransSub-subtopic2} -------------------- - Due to obstructed venous return - Face, lips, tongue, and internal organs - Edema from **rapid transudation** occurs with continued venous obstruction. - Pulmonary: may cause froth expression from the mouth and nostrils - 🖊️Because of the mixing of the edema, exudates, air, and surfactant that makes this bubbly froth ENGORGEMENT OF THE RIGHT HEART AND GREAT VEINS {#engorgement-of-the-right-heart-and-great-veins.TransSub-subtopic2} ---------------------------------------------- - Very non-specific - May be seen in any congestive death CYANOSIS {#cyanosis.TransSub-subtopic2} -------- - Greek: "dark blue" - Depends on the amount of reduced hemoglobin - 🖊️ If the victim is already suffering from severe anemia, even though the person is a victim of asphyxia, cyanosis may not be prominent - Invariably follows congestion of the head and neck in strangulation, the rest of the body follows with airway occlusion. - 🖊️ Very non-specific. You find these in several natural disease conditions whenever there is a lack of oxygen. Not necessarily due to a violent death by way of asphyxia DIFFERENT WAYS IN WHICH ASPHYXIA IS ACHIEVED {#different-ways-in-which-asphyxia-is-achieved.TransSubtopic1} -------------------------------------------- FATAL PRESSURE ON THE NECK {#fatal-pressure-on-the-neck.TransSub-subtopic2} -------------------------- 1. Hanging 2. Ligature strangulation 3. Manual strangulation 4. Mugging 5. Blows to the neck - Many victims do not present with the "classic signs" - 🖊️Or when they present with classic signs you don't find them together at the same time #### MECHANISM OF DEATH {#mechanism-of-death.TransSub-subtopic3} - Constriction of air passage cause anoxic asphyxia - Constriction of jugular veins and carotid arteries causes congestion and cerebral anoxia - Vasovagal cardiac inhibition due to pressure on the carotid sinus - Death may be immediate or within seconds - Injury to the spinal column and spinal cord - More in hanging #### SIMILAR POST-MORTEM FINDINGS IN HANGING AND LIGATURE STRANGULATION {#similar-post-mortem-findings-in-hanging-and-ligature-strangulation.TransSub-subtopic3} - Face swollen - The tongue may be protruded and dark - Lips are livid - Venous system filled with dark-colored fluid blood - The right side of the heart distended - Congested blood vessels of the brain, lungs, and visceral organs - The skin at the site of the ligature is hard with a red line of congestion and hemorrhage - 🖊️ The difference between hanging and ligature strangulation by the way is the manner. When you say hanging, the constricting force is the weight of the body of the victim -- but either way, you have some ligature around the neck. In ligature strangulation, it's some other constricting force. Either someone else is constricting the ligature around the victim's neck or some device created by a suicidal person to basically constrict his/her own neck. - 🖊️ You can't distinguish them by swollen face or livid lips because in both instances in hanging and ligature strangulation you would find these findings #### DISSIMILAR POST-MORTEM FINDINGS IN HANGING AND LIGATURE STRANGULATION {#dissimilar-post-mortem-findings-in-hanging-and-ligature-strangulation.TransSub-subtopic3} **Table 2. Difference between Hanging and Strangulation** ---------------------------------------------------------------------------------------- --------------------------------------------------------- **HANGING** **LIGATURE STRANGULATION** Face is usually pale Face is livid Eyes and pupils usually more open/dilated on the side of the knot (facies sympathique) Eyes wide open pupils dilated Saliva dribbled with froth from the mouth Bloody froth from mouth and nostrils and in big bronchi Petechial hemorrhages: more subpleural, subpericardial Petechial hemorrhages: more subconjunctival, face, neck Urination and Defecation Penis may be erected or semi erected Post mortem lividity marked at legs - However, you can distinguish them, particularly with these findings. In hanging, the face is pale because the constricting force can typically be strong enough to occlude not only the veins, the jugular vein, but also the carotids. And that's why the face is usually pale. Also, in hanging, the blood is gravitating through the feet or the lower part of the body. In ligature strangulation, the face is livid because the constricting force typically is not strong enough to occlude the carotid artery as well. It requires a greater amount of external pressure kasi to compress and entirely occlude the carotid artery and that's not easily achieved in ligature strangulation. - In hanging, the eyes and the pupils are asymmetric, often times it's more open/dilated on the site of the knot and we call this the facies sympathique or sometimes it's called facies sympathetique and this is because the knot on the side, if it's on the side of the neck, it can stimulate the **cervical sympathetic trunk** and this causes the eyes or the pupils on that side to open or dilate more on the opposite side, so you don't have this typically in ligature strangulation, because the application of the constriction is typically uniform around the neck. - In hanging strangulation, the saliva is often found to be dribbling with froth at the side of the mouth this is due to the knot again possibly **stimulating the submandibular salivary gland**. You won't find this in ligature strangulation because the force is uniform, but what you can find instead would be bloody froth from the mouth and nostrils and in big bronchi. - Urination and defecation are a result of the **relaxation of the sphincters post-mortem** - Penis may be erected or semi erected but that's not indicative of sexual activity prior to hanging, it just occurs. - Postmortem lividity will be marked in the legs because the legs will be the most dependent portion of the body in a person who hanged himself/herself **Table 3. Anatomic Sites Affected by Hanging Vs. Ligature Strangulation** ---------------------------------------------------------------------------- ------------------------------------------------------------------ ---------------------------------------------------- **HANGING** **LIGATURE STRANUGLATION** Hyoid bone Frequently injured (ligature usually at the level of Hyoid bone) Usually spared (ligature usually below the larynx) Ligature mark Inverted V shape Usually horizontal knot on the same plane Ligature Groove Deepest opposite knot Usually uniform in depth in its whole course Vertebral Injury Frequent Infrequent - Vertebral injury is frequent in hanging because of the sheer force of the weight of the body coming down on one's neck. #### ANTE-MORTEM HANGING {#ante-mortem-hanging.TransSub-subtopic3} - Redness or ecchymosis at the site of ligature - Ecchymosis of the pharynx and epiglottis - Line of redness or rupture of the intima of the carotids - Tardieu spots - Facies sympathique and saliva dribbling or dribbled from the mouth - (+) vital reaction except: - Generally, as long as there is a vital reaction, its ante mortem. This is the usual rule that we apply. Of course there's an exception to that rule say if, it might be that there is a vital reaction even though the hanging was post mortem hanging was done immediately after death, you might still appreciate some vital reaction there so that can be false positive indication of the antemortem nature of the hanging. - If postmortem, (-) vital reaction except in immediate post-mortem hanging - In the same vein, generally if there is no vital reaction, then you can consider the hanging post mortem, but there's some instances where even though there's no vital reaction, it is still an ante mortem injury/ antemortem hanging like say for instance if the ante mortem hanging have occurred in an **agonal state** had led to **near instantaneous death** such as there is no sufficient time for the body to mount the vital reaction, in which case you would have a negative vital reaction even though it was an antemortem ACCIDENTAL, HOMICIDAL, SUICIDAL {#accidental-homicidal-suicidal.TransSub-subtopic2} ------------------------------- - The rule is that hanging is suicidal and strangulation is homicidal unless there is evidence to the contrary - Suicidal strangulation by ligature is very rare - 🖊️ because this is difficult to achieve - Accidental hanging and strangulation by ligature are very rare 🖊️ When they do occur, you have to think about how is it that this person/victim has not been able to extricate themselves from the situation, maybe the **person was intoxicated, was incapacitated in some way, has some disability, or might be a minor.** HOMICIDAL vs SUICIDAL HANGING {#homicidal-vs-suicidal-hanging.TransSub-subtopic2} ----------------------------- - 🖊️ When it comes to hanging, again, the rule is that it's a suicide, unless there's evidence to the contrary. These are the evidence that might at least raise the suspicion for homicide. - Signs of forcible entry: homicidal - 🖊️ because you don't typically see or you're not expecting this in suicidal cases. - Compatible surroundings with self-suspension: suicidal - Objects used are easily accessible: suicidal - Unusual position of the body when found: suicidal - Feet or knee may be partially touching the floor 🖊️ indicates that this person has no desire to continue to live or to save himself/herself. Because if they wanted to, they could have easily stood up. - (-) signs of struggle on the body and clothing: suicidal - Clenching of the hand and no effort to free himself #### THROTTLING/MANUAL STRANGULATION {#throttlingmanual-strangulation.TransSub-subtopic3} - 🖊️ Fatal pressure to the neck by using hands or it is impossible to do this on your own, there can't be a suicidal throttling Figure 3. an example of a victim of throttling 🖊️ (GREEN CIRCLES:) Typically the victims of manual strangulation or throttling would have discoid 1- 2 cm in diameter contusions, these are impressions of the finger pads of the assailant, (RED CIRCLES:) and sometimes you would see these scratches around the **neck the vertical scratches those are indicators usually of the victim trying to get the hands of the assailant off of his neck**, these are self-inflicted scratches, in an effort to remove the hands of the assailant #### MUGGING {#mugging.TransSub-subtopic3} - 🖊️Applying fatal neck pressure using any other part of the body except the hands. Could be the knees, could be feet or as seen in the picture, the forearm.  Figure 4. Mugging #### BLOW TO THE NECK/ COMMANDO PUNCH {#blow-to-the-neck-commando-punch.TransSub-subtopic3} - 🖊️ A chop/jab to the side of the neck and you could imagine that if this turns out to be fatal. It was not fatal because of constriction of the airways, the jugular vein, or the carotid artery, if this results in death, it's probably due to **triggering a vasovagal reflex that results in reflex cardiac arrest** A person holding another person\'s hand Description automatically generated Figure 5. Commando Punch #### GARROTE {#garrote.TransSub-subtopic3} - 🖊️ Constricting band around the neck of the victim and there's a screw at the back that tightens that band, that's how the garrote is done. We don't have that anymore.  Figure 6. Garrote COMPRESSION ASPHYXIA {#compression-asphyxia.TransOutline} ==================== - Also known as "Traumatic Asphyxia" or "Crush Asphyxia" - Immobility of the chest and abdomen due to external pressure - 🖊️ so you can't breathe kaya naging Traumatic Asphyxia. Sometimes it's also called Mechanical Asphyxia. - Rarely suicidal - 🖊️ a lot of it is accidental but could also be homicidal - Burking and death by crucifixion - 🖊️ burking is a homicidal kind of compression asphyxia. It is done by sitting on one's chest and also putting one's hand over the respiratory orifices of the victim so there's a component of suffocation. And in death by crucifixion, there is immobilization of the chest. - Crucifixion - Clothing may produce irregular patterns on the skin - Physical injuries brought about by the compressing material - Provides the **most extreme demonstration of the "classic signs"** - 🖊️ In fatal pressures to the neck, sometimes you see some classic signs of asphyxia, and sometimes you don't. In compression asphyxia, you definitely expect that. Figure 7. Gross conjunctival hemorrhages in traumatic asphyxia. The victim was a workman who was buried up to his chest in an avalanche of ash. (Source: Knight's Forensic Pathology)  Figure 8. Traumatic asphyxia showing gross congestion of confluent petechial hemorrhages of the face and parts of the shoulders. The victim had been buried up to the axillae in an avalanche of iron ore in a factory bunker. (Source: Knight's Forensic Pathology) 📖 Figure 9. Traumatic asphyxia showing gross congestion of the face and red blood-tinged froth exuding from the nostrils and mouth. The victim had lost the control of the tractor he was driving, fell out of the cab and was compressed under the overturned vehicle. (Source: Knight's Forensic Pathology) SMOTHERING {#smothering.TransOutline} ========== Closing of the external respiratory orifices Grossly: Abrasion bruising of the nose, mouth, and chin is rarely seen though unless quite violent Abrasion, bruising of buccal surfaces from pressure against teeth or dentures -- lacerations are rare unless there was a blow Congestion and cyanosis in smothering due to lying on an impervious surface (hypostatic in nature) CHOKING {#choking.TransOutline} ======= Blockage of upper airways due to impaction of some foreign body Most common foreign bodies: Vomitus Regurgitation of food Bolus of food False set of teeth Blood in tonsillectomy operation Respiratory hemorrhage 🖊️In children, probably toys and coins ⭐ Agonal or post-mortem spillage of gastric contents into the larynx, trachea, and bronchi is common 🖊️ Just because one finds some gastric contents in the larynx, trachea, or bronchi, you don't automatically assume that the person died of choking. It can be just a post-mortem phenomenon so look for corroborative evidence. Look for signs of asphyxia and perhaps other circumstantial evidence. 🖊️ Just post-mortem spillage if it's just gastric contents and no other foreign body in there. Not necessarily ante-mortem aspiration. The **"classic signs"** are expected in death from **pure hypoxia** when the victim **struggles to breathe** for a period. 🖊️Look for classic signs. If it's not there, then it can be just a post-mortem phenomenon. BREATHING IRRESPIRABLE CASE {#breathing-irrespirable-case.TransOutline} =========================== A. ASPHYXIA BY SUFFOCATION {#a.-asphyxia-by-suffocation.TransSubtopic1} -------------------------- CARBON MONOXIDE {#carbon-monoxide.TransSub-subtopic2} --------------- 🖊️ probably the most common one "silent killer" 🖊️ you can't hear it, you can't smell it, you can't see it From incomplete combustion of carbon fuel 🖊️ coal, charcoal, gasoline, kerosene Accidental and suicidal death is common **cherry red discoloration** -- the most characteristic feature in autopsies of those who died by carbon monoxide poisoning /intoxication 🖊️ (Externally especially in areas of lividity. Internally the blood and muscles) CARBON DIOXIDE {#carbon-dioxide.TransSub-subtopic2} -------------- From the complete combustion of carbon-containing compounds End result of fermentation and decomposition of organic matters (sewers, septic tanks, drainage pipes, deep wells) Cyanosed Frothy mouth Congestion of eyes Pupils dilated Internal organs are dark and congested HYDROGEN CYANIDE {#hydrogen-cyanide.TransSub-subtopic2} ---------------- One of the most toxic and rapid-acting gases **60-90 mg taken orally is fatal** Rapidly lethal, death in usually 1-2 mins Almond odor 🖊️ Not everybody can smell it Dark pink, bright red, or brick-red skin Tissues bright pink 🖊️ due to excess oxyhemoglobin Damaged gastric mucosa in oral forms 🖊️ The oral forms of hydrogen cyanide come in salts (sodium or potassium salts) which are very alkaline so once ingested they may cause damage to the gastric mucosa HYDROGEN SULFIDE {#hydrogen-sulfide.TransSub-subtopic2} ---------------- Rotten egg odor, sweetish taste From decomposition of organic substances with sulfur (sewers, septic tanks, drainage pipes, deep wells) SULFUR DIOXIDE {#sulfur-dioxide.TransSub-subtopic2} -------------- Pungent odor Usually in volcanoes 🖊️ active ones Disinfectant, bleaching agent, powerful reducing agent DROWNING {#drowning.TransOutline} ======== A. ASPHYXIA BY DROWNING {#a.-asphyxia-by-drowning.TransSubtopic1} ----------------------- Nostrils and mouth have been submerged in any watery, viscid, or pultaceous fluid for a time to prevent the free entrance of air into the air passages and lungs B. MECHANISM OF DEATH IN IMMERSIONS {#b.-mechanism-of-death-in-immersions.TransSubtopic1} ----------------------------------- Drowning: inhaled water interfering with gas exchange Reflex cardiac arrest 🖊️ because the water especially cold water may trigger the vasovagal reflex and cause cardiac arrest or just anxiety Tachyarrhythmias 🖊️ and that might cause death instead of drowning itself Laryngeal spasm 🖊️ Just the water coming in contact with the pharynx might cause a spasm of the larynx preventing water from submerging/drown your lungs **Time required for death in drowning** Submersion for 1-1.5 minutes is usually fatal Average: 2-5 minutes 🖊️ but there are cases of people surviving much longer period of time in the water even up to 60 minutes C. CONCERNS IN AUTOPSY DIAGNOSIS OF DROWNING {#c.-concerns-in-autopsy-diagnosis-of-drowning.TransSubtopic1} -------------------------------------------- +-----------------------------------+-----------------------------------+ | Bodies retrieved in water... | All show signs of immersion 🖊️ | | | regardless of whether or not the | | | person died of drowning or fallen | | | into the water and died | | | beforehand. | +===================================+===================================+ | | May have died from: | | | | | | natural disease before falling | | | into the water | | | | | | natural disease while already in | | | the water | | | | | | injury before entering the water | | | | | | injury while in the water | | | | | | effects of immersion other than | | | drowning | | | | | | drowning | +-----------------------------------+-----------------------------------+ 🖊️ As much as possible, the medico-legal conducting the autopsy would have to differentiate all of these. If he finds injuries, he has to figure out whether it is antemortem or postmortem. If antemortem, did it contribute to death or not? Did it occur while the person is already in the water or prior entering the water? D.SIGNS OF IMMERSION {#d.signs-of-immersion.TransSubtopic1} -------------------- MACERATION (WATERLOGGING OF SKIN) {#maceration-waterlogging-of-skin.TransSub-subtopic2} --------------------------------- Within minutes in warm water (e.g. bathtub) Variable time of appearance in cold water 🖊️ might take longer Areas protected by clothing develop changes later than exposed parts Skin becomes wrinkled, pale and sodden first signs often in hands and soles (washer-woman\'s hands and feet) 🖊️ areas where the stratum corneum is thick then eventually over wide areas of the body (e.g., extensor surface of knees and elbows) After prolonged immersion, nails and hair become loosened at about the same time 🖊️ You'll find this in all corpses immersed in a body of water CUTIS ANSERINA ("GOOSE FLESH") {#cutis-anserina-goose-flesh.TransSub-subtopic2} ------------------------------ Related to cold rather than warm water Due to contraction of erector pilae muscles attached to hair follicles causing generalized pimpling of the skin n.b. the erector pilae muscles can contract in any type of agonal death MARKED HYPOSTASIS AT HEAD AND NECK ("TETE DE NEGRI" {#marked-hypostasis-at-head-and-neck-tete-de-negri.TransSub-subtopic2} --------------------------------------------------- Because it\'s usual for a corpse to float in the water with buttocks uppermost, and the head and limbs hanging down n.b. water movements often roll the body constantly unless in a placid lake or wide river electrocution in bath --- margin of hypostasis corresponds with the horizontal line of the water level PINK HYPOSTASIS {#pink-hypostasis.TransSub-subtopic2} --------------- in bodies in cold water Due to unreduced oxyhemoglobin in the superficial blood vessels resulting from the exposure to cold environment n.b. also seen in ante-mortem hypothermia, and bodies from mortuary refrigerators or any cold environment Antemortem hypothermia has typical distribution over extensor surfaces and large joints, and dusky tinge Differentiates ante-mortem and postmortem AQUATIC ARTIFACTS ON/IN THE BODY {#aquatic-artifacts-onin-the-body.TransSub-subtopic2} -------------------------------- Mud, coal-slurry, oil, silt or sand, seaweed, water weed, algae, and small aquatic animal life 🖊️ Signs of immersion but does not tell you anything about the cause of death Might help establish where the body has traveled 🖊️ Certain artifacts that are specific to a certain region 🖊️ May tell where the body came from Sand might be found in the respiratory passages and stomach 🖊️Not a sign of drowning, not really dependent on life or swallowing prior to death. Where a body is decomposed and partly skeletonized, mollusks may colonize the bones E. ESTIMATION OF THE DURATION OF IMMERSION {#e.-estimation-of-the-duration-of-immersion.TransSubtopic1} ------------------------------------------ 🖊️ can we estimate the duration of immersion just from examining the signs of immersion? The short answer to that is NO, but there have been studies regarding this. Overriding variable factor water temperature Water pollution has little effect on the speed of putrefaction 🖊️ because the putrefactive organisms come from our own guts 🖊️ It really is more dependent on the water temperature The average time scale in a temperate climate: 🖊️ we cannot apply it in our situation, because this is limited to temperate climates alone and we live in a tropical country Few hours -- no wrinkling of the finger-pads is present 1⁄2 -- 3 Days -- progressive wrinkled fingers, palms and feet 4-10Days -- early decomposition (dependent head and neck, abdomen and thighs) 2-4 Weeks -- bloating of face and abdomen, marbling, peeling of epidermis on hands and feet, and spillage of scalp 1-2 Months -- gross skin shedding, muscle loss with skeletal exposure, partial liquefaction F. SIGNS OF DROWNING {#f.-signs-of-drowning.TransSubtopic1} -------------------- 🖊️if you find them they are indicative of drowning, not just indicative of immersion Positive signs of drowning progressively fade with increasing postmortem interval 🖊️ It is possible that the corpse you find in the body of water did die of drowning, but you don't see the signs of drowning anymore because of the long postmortem interval Nothing absolutely specific 🖊️ You might find the signs of drowning and still it is not enough to conclusively say that the person has died of drowning. You have to take in all the evidence available as much as possible. FROTH IN THE AIR PASSAGES {#froth-in-the-air-passages.TransSub-subtopic2} ------------------------- Proteinaceous exudate and surfactant mixed in the water of the drowning medium Often exudes through mouth and nostrils (champignon d'ocume) Extends into the trachea, main bronchi, and smaller air passages WATERLOGGED LUNGS (EDEMA AQUOSUM) {#waterlogged-lungs-edema-aquosum.TransSub-subtopic2} --------------------------------- Very characteristic of drowning Lungs are so filled with water, so soaked and saturated with water However, absence does not exclude drowning (dry-drowning) Dry-lung drowning Lungs appear normal in all respects All the aspirated water has been absorbed through the alveolar walls into the plasma Theory: After the water enters the lungs there is a laryngeal spasm that prevents further entry of water in the lungs and allows circulation to clear out the water that went into the lungs and into the plasma Theory: After the drowning the victim is taken out of the water soon enough, preventing further water from entering the lungs and preventing the lungs from becoming entirely water-logged Seen in 10-20% of drownings Edema fluid in the lungs Doughy lungs that readily pit on pressure Exudes water and froth from surfaces and when squeezed OVERINFLATION OF THE LUNGS (EMPHYSEMA AQUOSUM) {#overinflation-of-the-lungs-emphysema-aquosum.TransSub-subtopic2} ---------------------------------------------- 🖊️ Positive sign of drowning 🖊️ The lungs of those who drown are typically overinflated, when you cut through the sternum it will be bursting out of the thoracic cavity. Lungs fill the thoracic cavity when sternum is removed Lungs may cover the heart and anterior mediastinum May cause rib impressions the lateral surface of the lungs Pale and crepitant texture When you try to press it The edema fluid in the bronchi blocks the passive collapse that normally occurs at death, holding the lungs in the inspiratory position N.b True pre-existing emphysema may have bullae A way to differentiate emphysema from emphysema aquosum G. NOW CONSIDERED UNRELIABLE SIGNS OF DROWNING {#g.-now-considered-unreliable-signs-of-drowning.TransSubtopic1} ---------------------------------------------- Heart and great veins are dilated and engorged with fluid blood Blood remaining more fluid Stomach containing watery fluid or foreign material in the water (e.g., silt, weed or sand) Hemorrhage in the middle ears and temporal bone Still considered as a sign of drowning in Solis' Book, but the current thinking is that it it not seen in those who are definitively drowning Fluid in the middle ear or paranasal sinuses Gettler's test Post-mortem changes in \[Cl\] blood occur irrespective of drowning the rate change may be different on each side of the heart 🖊️ makes use of the chloride concentration in the left and right side of the heart. It makes a comparison, if there is a 25mg or 100 mL difference of the concentration in the left and right side of the heart, it is said to be a positive Gettler's test. But proven to be entirely unreliable, so we don't use it anymore H. DIATOM TEST {#h.-diatom-test.TransSubtopic1} -------------- Diatoms Microscopic algae with a silicaceous exoskeleton Very resistant to acids Principle When a dead body enters the water, diatoms cannot progress further than the lungs 🖊️you find diatoms practically everywhere, you go into the water and inhale it these diatoms will go into your lungs. If it was a dead body that went into the water the diatoms cannot progress further into the lungs. Because the diatoms in order to go into the other organs will require circulation and requires a beating heart. You examine the heart, brain, and kidneys and examine it under the microscope. You should be able to appreciate diatoms, if supposing the victim died of drowning. Limitations Diatoms are ubiquitous You find them everywhere. Not just water, you find them in air and soil. There is a great chance of contaminations Diatoms may enter intestinal lining, and gain access to the bloodstream and hence any body tissues Certain foods, notably shellfish, contain vast quantities of diatoms Diatoms have been seen in many non-drowning cases Diatoms have not been seen in some drowning case Used only as an indicative aid and not as legal proof of drowning I. ACCIDENTAL, HOMICIDAL, SUICIDAL? {#i.-accidental-homicidal-suicidal.TransSubtopic1} ----------------------------------- Suicidal Heavy articles or weight may be found in the pocket of clothing of the victim Indicating the desire to sink in the bottom of the body of water Homicidal Articles belonging to the assailant may be found near the place where the deceased was recovered Ligature on the hands of legs which could not be possibly applied by the victim himself Accidental If there is exclusion of suicidal or homicidal nature of drowning GUIDE QUESTIONS {#guide-questions.TransOutline} =============== **1.** **What are the types of asphyxial deaths according to mechanism?** +-----------------------------------+-----------------------------------+ | **Types of Asphyxial deaths** | | +===================================+===================================+ | **Anoxic** | - Failure of arterial blood to | | | be normally saturated with | | | oxygen | | | | | | - This might happen if | | | there is an obstruction | | | to the air passages | | | because of smothering, | | | choking, or compression | | | of the chest. | +-----------------------------------+-----------------------------------+ | **Anemic anoxic** | - Decreased capacity of blood | | | to carry oxygen | | | | | | - This might occur in | | | carbon monoxide poisoning | | | or severe hemorrhage | | | where you have severe | | | anemia | +-----------------------------------+-----------------------------------+ | **Histotoxic anoxic** | - Failure of the cellular | | | oxidative process | | | | | | - We have oxygen in the | | | blood, there is no | | | failure there, there is | | | no failure to carry, | | | there is no decreased | | | capacity or incapacity of | | | the blood to carry oxygen | | | but for whatever reason, | | | we cannot utilize the | | | oxygen at the cellular | | | level. A classic example | | | of this would be cases of | | | cyanide poisoning. | | | | | | - Cyanide and alcohol are | | | common agents responsible | | | for histotoxic anoxic | | | death | +-----------------------------------+-----------------------------------+ | **Stagnant anoxic** | - Failure of circulation | | | | | | - Pulmonary embolism or | | | those with heart failure | | | | | | - Shock, arterial and | | | venous obstruction, | | | vascular spasm, varicose | | | veins, or the use of | | | tourniquet | +-----------------------------------+-----------------------------------+ **2. What are the classic signs of asphyxia?** - [Petechial hemorrhages] - Small pin-point collections of blood (0.1-2 mm) - Skin - Under the scalp - Scleral or subconjunctival - Under thoracic serous membranes such as the visceral pleura ★ ("TARDIEU SPOTS") or pericardium - When in the brain, often in the white matter - Due to rupture of small venules from acute rise in venous pressure - May vanish with putrefaction and freshwater immersion - Very non-specific - Often present in normal post-mortem hypostasis - Found in interlobar fissures and around the hilum in most routine autopsies - May occur with violent coughing or sneezing - ★ Most significant if facial or ocular - Unless the body was face down or head down - [Congestion and edema] - Due to obstructed venous return - Face, lips, tongue, and internal organs - Edema from rapid transudation occurs with continued venous obstruction. - Pulmonary: may cause froth expression from the mouth and nostrils - [Engorgement of right heart and great veins] - Very non-specific - May be seen in any congestive death - [Cyanosis ] - Greek: "dark blue" - Depends on the amount of reduced hemoglobin - Invariably follows congestion of the head and neck in strangulation, the rest of the body follows with airway occlusion. - Very non-specific. You find these in several natural disease conditions whenever there is a lack of oxygen. Not necessarily due to a violent death by way of asphyxia **FATAL NECK PRESSURES:** **1. What are the mechanisms of death associated with fatal pressures to the neck?** - [Constriction of air passage] cause anoxic asphyxia - [Constriction of jugular veins and carotid arteries] cause congestion and cerebral anoxia - [Vasovagal cardiac inhibition] due to pressure on the carotid sinus - Death may be immediate or within seconds - [Injury to spinal column and spinal cord] - More in hanging **2. What are the forms of fatal neck pressures?** - The distinction between these entities is attributed to the cause of the external pressure on the neck: - [Hanging] - Either a constricting band tightened by the gravitational weight of the body or part of the body - Complete hanging is defined by the full weight of the patient being suspended by the neck. - Incomplete hanging injuries encompass all injuries in which the patient is supported partially by another object such as the ground or furniture. - [Ligature strangulation] - A constricting band tightened by a force other than the body weight  - [Manual strangulation] - Fatal pressure to the neck by using hands - [Mugging] - Applying fatal neck pressure using any other part of the body except the hands. Could be the knees, feet, forearm. - [Blows to the neck] - A chop/jab to the side of the neck - [Garrote] - Constricting band around the neck of the victim and there's a screw at the back that tightens that band - Obsolete ( ) **3. Compare and contrast autopsy findings in hanging and ligature strangulation** +-----------------------------------+-----------------------------------+ | **HANGING** | **LIGATURE STRANGULATION** | +===================================+===================================+ | **DISSIMILAR POSTMORTEM | | | FINDINGS** | | +-----------------------------------+-----------------------------------+ | Face usually **pale** | Face is **livid** | +-----------------------------------+-----------------------------------+ | Eyes and pupils usually more | **Eyes wide open pupils dilated** | | open/dilated on the side of the | | | knot **(facies sympathique)** | | +-----------------------------------+-----------------------------------+ | **Saliva dribbled with froth** | **Bloody froth** from mouth and | | from the mouth | nostrils and in big bronchi | +-----------------------------------+-----------------------------------+ | Petechial hemorrhages: more | **Petechial hemorrhages: more | | subpleural, subpericardial | subconjunctival, face, neck** | +-----------------------------------+-----------------------------------+ | **Urination and defacation** | | +-----------------------------------+-----------------------------------+ | **Penis** may be **erected** or | | | semi erected | | +-----------------------------------+-----------------------------------+ | **Post mortem lividity marked at | | | legs** | | +-----------------------------------+-----------------------------------+ | **DISSIMILAR POSTMORTEM FINDINGS | | | IN THE NECK** | | +-----------------------------------+-----------------------------------+ | Hyoid bone frequently injured | Hyoid bone usually spared | | (ligature usually at the level of | (ligature is usually below the | | hyoid bone | larynx) | +-----------------------------------+-----------------------------------+ | **Ligature mark: Inverted V | **Ligature Mark:** usually | | shape** | **horizontal** knot on the same | | | plane | +-----------------------------------+-----------------------------------+ | **Ligature Groove: deepest** | **Ligature Groove: usually | | | uniform** in depth in its whole | | **opposite knot** | course | +-----------------------------------+-----------------------------------+ | **Vertebral injury: frequent** | Vertebral injury: infrequent | +-----------------------------------+-----------------------------------+ **4. How can antemortem hanging be differentiated from postmortem hanging?** - [Antemortem hanging] - Redness or ecchymosis at the site of ligature - Ecchymosis of the pharynx and epiglottis - Line of redness or rupture of the intima of the carotids - Tardieu spots - Facies sympathique and saliva dribbling or dribbled from the mouth - (+) Vital reaction except: - Generally, as long as there is vital reaction, its antemortem. This is the usual rule that we apply. And of course there's exception to that rule say if, it might be that there is a vital reaction even though the hanging was post mortem hanging was done immediately after death, you might still appreciate some vital reaction there so that can be false positive indication of the antemortem nature of the hanging. - Postmortem hanging - (-) Vital reaction except in immediate postmortem hanging - In the same vein, generally if there is no vital reaction, then you can consider the hanging post mortem, but there's some instances where even though there's no vital reaction, it is still an ante mortem injury/ antemortem hanging like say for instance if the ante mortem hanging have occurred in an agonal state had led to near instantaneous death such as there is no sufficient time for the body to mount the vital reaction, in which case you would have a negative vital reaction even though it was an antemortem **5. How is manner of death determined in case of hanging and ligature strangulation?** - Rule is that [hanging is suicidal and strangulation is homicidal unless there is evidence to the contrary] - [Suicidal strangulation by ligature is very rare ] - Because this is difficult to achieve - [Accidental hanging and strangulation by ligature are very rare ] - When they do occur, you have to think about how is it that this person/victim has not able to extricate themselves from the situation, may be the person was intoxicated, was incapacitated in some way, has some disability, or might be a minor. - [Homicidal vs Suicidal] - Homicidal - Signs of forcible entry - Suicidal - Compatible surroundings with self-suspension - Objects used are easily accessible: suicidal - Unusual position of the body when found (feet or knee may be partially touching the floor) - (-) Signs of struggle on the body and clothing (clenching of the hand and no effort to free himself) **COMPRESSION ASPHYXIA:** **1. What is compression asphyxia?** - Also known as "Traumatic Asphyxia" or "Crush Asphyxia" - Immobility of the chest and abdomen due to external pressure - Rarely suidical - Burking and death by crucifixion - Burking is a homicidal kind of compression asphyxia done by sittong on one's chest and also putting one's hand over the respiratory orifices of the victim so there's a component of suffocation. And in death by crucifixion, there is immobilization of the chest. - Clothing may produce irregular pattern on the skin - Physical injuries brought about by the compressing material - Provides the most extreme demonstration of the "classic signs" - Usually due to external compression of chest / abdomen by heavy weight - Commonly observed in soft drink vending machine tipping, motor vehicle accidents, cave related accidents and mass disasters (earthquake, collapsed buildings) - Primary mechanism of death is flail chest - Frequently observed in children: - Overlaying asphyxia: when a heavy sleeping adult may move on top of the infant, causing compression asphyxia - Wedging: when the body is compressed between 2 firm surfaces, preventing breathing **2. What are the autopsy findings associated with compression asphyxia?** - Autopsy findings: - Related to the thoracoabdominal compression, which results in venous hypertension in the valveless cervicofacial venous system - [Facial and conjunctiva severe congestion and cyanosis] - [Conjunctival hemorrhage] - [Facial and upper chest petechiae] - [Heavy and dark red lungs with or without subpleural petechiae] - [Hemorrhage in the soft tissues may be present] [(][)] **SUFFOCATION:** **1. What are the different forms of suffocation?** - [Smothering] - Closing of the external respiratory orifices - [Choking] - Blockage of upper airways due to impaction of some foreign body - Most common foreign bodies: - Vomitus - Regurgitation of food - Bolus of food - False set of teeth - Blood in tonsillectomy operation - Respiratory hemorrhage - In children, probably toys and coins - [Breathing irrespirable gases] - Carbon monoxide - Carbon dioxide - Hydrogen cyanide - Hydrogen sulfide - Sulfur dioxide **2. What are the autopsy findings associated with different forms of suffocation?** - [Smothering] - Grossly: - Abrasion bruising of the nose, mouth and chin rarely seen though unless quite violent - Abrasion, bruising of buccal surfaces from pressure against teeth or dentures -- lacerations are rare unless there was a blow - Congestion and cyanosis in smothering due to lying on an impervious surface (hypostatic in nature) - [Choking] - ★ Agonal or post-mortem spillage of gastric contents into larynx, trachea and bronchi is common - [Breathing irrespirable gases] - Carbon monoxide - Cherry red discoloration -- most characteristic feature in autopsies of those who died by carbon monoxide poisoning /intoxication (Externally especially at areas of lividity. Internally the blood and muscles) - Carbon dioxide - Cyanosed - Frothy mouth - Congestion of eyes - Pupils dilated - Internal organs are dark and congested - Hydrogen cyanide - Dark pink, bright red or brick red skin - Tissues bright pink - Damaged gastric mucosa in oral forms - Hydrogen sulfide - Marked facial congestion - Massive pulmonary hemorrhagic edema - Hyperemia of trachea and bronchus - Discoloration of lividity - Accentuation of the gray matter of the brain.  - Sulfur dioxide - Coagulated appearance of the pharynx and larynx () **3. What are the important scene findings to note in case of breathing of irrespirable gases?** - Carbon monoxide - From incomplete combustion of carbon fuel (coal, charcoal, gasoline, kerosene) - [Carbon dioxide] - From complete combustion of carbon containing compounds - End result of fermentation and decomposition of organic matters (sewers, septic tanks, drainage pipes, deep wells) - [Hydrogen cyanide] - Almond odor (not everybody can smell it) - One of the most toxic and rapid acting gases - [Hydrogen sulfide] - Rotten egg odor, sweetish taste - From decomposition of organic substances with sulphur (sewers, septic tanks, drainage pipes, deep wells) - [Sulfur dioxide] - Pungent odor - Usually in volcanoes (active ones( - Disinfectant, bleaching agent, powerful reducing agent **DROWNING:** **1. What is drowning?** - Inhaled water interfering with gas exchange **2. What are the mechanisms of death in drowning?** - [Reflex cardiac arrest ] - Because the water especially cold water may trigger the vasovagal reflex and cause cardiac arrest or just anxiety - [Tachyarrhythmias ] - Might cause the death instead of the drowning itself - [Laryngeal spasm] - Just the water coming in contact with the pharynx might cause spasm of the larynx preventing water to submerge/drown your lungs **3. What are the autopsy findings in drowning?** - [Froth in the air passages] - Proteinaceous exudate and surfactant mixed in the water of the drowning medium - Often exudes through mouth and nostrils (champignon d'ocume) - Extends into trachea, main bronchi and smaller air passages - [Waterlogged lungs (Edema aquosum)] - Very characteristic of drowning - Lungs are so filled with water, so soaked and saturated with water. However, absence does not exclude drowning (dry- drowning) - Dry-lung drowning - Lungs appear normal in all respects - All the aspirated water has been absorbed through the alveolar walls into the plasma - Theory: after the water enter the lungs there is laryngeal spasm that prevents further entry of water in the lungs that allows circulation to clear out the water that went into the lungs and into the plasma - Theory: after the drowning the victim is taken out of the water soon enough, preventing further water from entering the lungs and preventing the lungs from becoming entirely water-logged - Seen in 10-20% of drownings - Edema fluid in the lungs - Doughy lungs that readily pit on pressure - Exudes water and froth from surfaces and when squeezed - [Overinflation of the lungs (Emphysema aquosum)] - Lungs fill thoracic cavity when sternum is removed - Lungs may cover the heart and anterior mediastinum - May cause rib impressions the lateral surface of the lungs - Pale and crepitant texture - When you try to press it - The edema fluid in the bronchi blocks the passive collapse that normally occurs at death, holding the lungs in the inspiratory position - True pre-existing emphysema may have bullae - A way to differentiate emphysema from emphysema aquosum **4. How is manner of death determined in drowning cases?** - [Suicidal] - Heavy articles or weight may be found in the pocket of clothing of the victim - Indicating the desire to sink in the bottom of the body of water - [Homicidal] - Articles belonging to the assailant may be found near the place where the deceased was recovered - Ligature on the hands of legs which could not be possibly applied by the victim himself - [Accidental] - If there is exclusion of suicidal or homicidal nature of drowning \[2025\] REVIEW QUESTIONS {#review-questions.TransOutline} ========================= 1\. Spillage of gastric contents in the larynx, trachea, and bronchi is a common postmortem phenomenon. a. True b. False +-----------------------------------------------------------------------+ | **RATIONALE** | | | | ANSWER: A | | | | - Agonal or post-mortem spillage of gastric contents into larynx, | | trachea and bronchi is common | | | | - Just because one finds some gastric contents in the larynx, | | trachea, or bronchi, you don't automatically assume that the | | person died of choking. It can be just a post-mortem phenomenon | | so look for corroborative evidence. | +-----------------------------------------------------------------------+ 2\. The presence of all the classic signs of asphyxia is conclusive evidence of asphyxia. a. True b. False +-----------------------------------------------------------------------+ | ANSWER: B | | | | - Classic signs of asphyxia are non-specific | | | | - Asphyxia diagnosis requires other corroborating evidence. | | | | - Especially finding of a cause for mechanical obstruction of | | respiration | +-----------------------------------------------------------------------+ 3\. A dead person found immersed in water but whose lungs appear normal in all aspects could not have died of drowning. a. True b. False +-----------------------------------------------------------------------+ | ANSWER: B | | | | - Dry-lung drowning | | | | - Lungs appear normal in all respects | | | | - All the aspirated water has been absorbed through the | | alveolar walls into the plasma | | | | - Seen in 10-20% of drownings | +-----------------------------------------------------------------------+ REFERENCES {#references.TransOutline} ========== - Atty./Dr. Apostol, K. (2024). Asphyxia \[lecture video\]. - Saukko, P. and Knight, B. (2016) Knight's Forensic Pathology. CRC Press, Boca Raton. APPENDIX ======== - No appencides