Lecture 5 Asphyxia- drowning (1)NOTES .pptx

Forensic medicine notes for medical laboratory students ,second years.

1.  Died from natural disease before falling into the water  Died from natural disease while already in the water  Died from injury before being thrown into the water  Died from injury while in the water  Died from effects of immersion other than drowning  Died from drowning.

2. Breath Holding Lasts for a variable length of Carbon dioxide accumulation Stimulation of the respiratory centre in brain Inevitable inhalation of large volumes of water.

3.  • Swallowing Of Water Coughing, vomiting progressive loss of consciousness Escape of air remaining In the lungs and replaced by water

4.  Profound unconsciousness and convulsions Gasping Respiratory standstill Failure of heart Irreversible changes in the brain Death

5. Maceration of the skin in warm water ‘Washer-woman’s skin Keratin of hands and feet peels off in ‘glove and stocking’ fashion Nails and hair loosened Cutis anserina – or ‘goose-flesh’ –cold water. Float with buttocks uppermost, head and limbs down

6.  Wrinkled fingers, palms and feet, half a day to 3 days  Decomposition, Often first in the dependent head and neck, abdomen and thighs: 4–10 days Bloating of face and abdomen with marbling of veins and peeling of epidermis on hands and feet, and slippage of scalp: 2–4 weeks Gross skin shedding, muscle loss with skeletal exposure, partial liquefaction: 1–2 months.

7. or suicidal in j u r i es m ay be  Myocardial infarct  Oc c a s io n al l y , a c ci d e nt al inflicted  Trauma in the water is common  Sudden entry of cold water into the pharynx and larynx, and perhaps nasal passages can produce powerful stimulation of nerve endings in the mucosa.  A bolus of water entering the trachea can also cause reflex cardiac arrest.

8.  Drowning is a form of asphyxial death due to aspiration of fluid into the air passages by submersion of the body in water or fluid medium.  Complete submersion not necessary, submersion of nose and mouth is enough.

9. Classification  Typical  Atypical Typical drowning  Obstruction of air passages and lungs by inhalation of fluid and is known as “Wet drowning”.  Typical signs are found at autopsy.

10. Atypical drowning  Condit i ons in whi c h t h ere is very li t tle or no inhalation of water or fluid in the air passages.  Dry drowning.  Immersion syndrome(vagal inhibition).  Submersion of the unconscious.  Secondary drowning syndrome/near-drowning.

11. Typical drowning  Fresh water drowning.  Salt water drowning. Fresh water drowning Water cross the alveolar membrane into the circulation. Produces marked hypervolaemia. Re d c e lls swell o r b u r s t - he m o l y s i s - li b era t i o n of potassium. Circulation will suffer 50% dilution within 2-3 min.

12. The heart is submitted to the insult of anoxia, hypervolaemia, potassium excess and sodium deficit. Ventricular fibrillation due to anoxia and potassium excess within 4-5 min. Salt water drowning Marked hyper tonicity of the inhaled water cause loss of fluid from circulation into the lungs-fulminating pulmonary edema and progressive hypovolaemia. Circulatory shock and cardiac arrest.

13. Atypical drowning Dry drowning Intense laryngeal spasm due to entry of water into nasopharynx and larynx. Very little water enters into lungs. Best case for resuscitation. Immersion syndrome  Due to sudden impact with very cold water and causes death from cardiac arrest.  Victims are young people with excess of alcohol.

14. It also result from falling or diving with feet or duck diving by the inexperienced swimmers. Loss of con sciousness instantaneous and death occu rs in few minutes. Autopsy disclose non of the usual signs of drowning. Submersion of the unconscious Commonly seen if the victim is suffering from disease like epilepsy, heart diseases and is drunk or head injury during fall.

15. Ballooning of the lungs may be absent. Formation of the foam m a y be negligible. Complete picture of death by drowning is not found. Secondary drowning/near-drowning Its mainly due to infection from inhalation of contaminated water. Lung complications, oxygen lack, tired heart muscle and cerebral edema.

16. A victim look alert a nd bre a th i n g, m ay re s pond t o ini t i a l resuscitation. hypotension and c ardi a c Late s tag e - re s p irat o ry dist r ess, arrhythmia may cause death.

17. Vicious cycle of drowning  Deep inspiration  Need for air Water enters resp.passa g e  Air driven out of lungs Cough reflex

18. Medico legal aspects Whether the death was due to drowning or other cause? Length of time the body was in water. Whether it was accidental/suicidal/homicide? “Brides of the bath case”

19. Postmortem findings External findings  Fine froth at the nose  Consists of a proteinaceous exudates and surfactant mixed with the water of the drowning medium. It is usually white, but may be pink or red-tinged, because of slight admixture with blood from intrapulmonary bleeding.  Rarely the presence of weeds, mud etc.

20. Cutis Anserina (goose Skin , goose pimples ) Due to spasm of the erector pilae muscles and due to exposure to cold water at the time of death. S kin appears granular and puckered,with hair standing on the end. Extremities are mainly affected.

21. The skin of the finger,palms and later the soles of the feet may be wrinkled,bleached and sodden. Due to osmotic action of water,on thickened epidermis. Th i s i m m e r sion changes known a s Ha n ds a n d Fee t of a Washer-Woman.

22. Internal findings  Lungs & respiratory tract:- Airways filled with froth, sand, weeds etc found in the water. Lungs are voluminous, edematous,doughy to feel with rib markings. Paltauf’ hemorrhages seen. C/s:- Oozing out of blood stained frothy fluid and ballooning of the lungs is known as “Emphysema Aquosum”. Wt up to 2 kgs.

23. Watery fluid transudates into pleural cavities during putrefaction. Hydrostatic lung:- 2meters depth-20min. Hemorrhages in the middle ear & mastoid air cells. The stomach may contain watery fluid or even foreign material from the water, such as silt, weed or sand,

24. Diatoms  Microscopic unicellular algae present in water.  Silicaceous cell wall which resists acid digestion, heat and putrefaction.  Size 10-80 microns.  Only a live body with a circulation can transport diatoms from lungs to the brain or bone marrow.  Isolation- acid digestion of tissue commonly bone marrow, lung, blood and kidney-centrifugation and washing. residue is examined under phase contrast microscopy.

25. Principle of diatome test for drowning. When dead body enters the water, diatomes progress further than the lungs.

26. Cause of death Asphyxia Ventricular fibrillation Laryngeal spasm. Vagal inhibition. Exhaustion. Injuries. Fatal period 4-8min.

27. Diagnosis of drowning  Froth  Weeds & gravel/soil in hand.  Voluminous lungs.  Diatoms in tissues.

28. T hank You