2. Forensic Pathology Medicolegal investigation of death

3. “The psychiatrist knows nothing and does nothing. The surgeon knows nothing and does everything. The pathologist knows everything… but is always a day too late.” -TRADITIONAL MEDICAL MAXIM

4. Coroners vs. Medical Examiners Coroners- elected position, more often found in rural areas. Medical examiners- physician (usually a pathologist)

5. When are autopsies performed? Sudden and/or unexpected death Public health concern (ex. Mysterious disease) If someone dies unattended by a physician Family asks for an autopsy If an autopsy is not required by law, the next-of kin must give permission Laws vary from state to state.

6. Example Someone witnesses a suicide Know ID of person, time of death, cause of death. Why do an autopsy? –Show contributing factors to the suicide Terminal disease Pregnancy Drugs/alcohol

7. Example Someone observes a car accident in which someone else leaves the roadway, hits a tree and is killed instantly. The autopsy may reveal contributing factors: Blackout Myocardial infarction Alcohol/drugs

8. Parts of an autopsy External examination »Look for bruising, cuts, wounds, etc… Internal examination »Weigh organs »Check for abnormalities »Preserve in formaldehyde Microscopic examination »Histology – study of tissues Toxicology report »Blood, urine, bile, fluid from the eye »Looking for meds, drugs, alcohols, poison

9. Cause of Death What caused life to cease? Ex. Blunt trauma to the head Ex. Bullet to the heart Ex. Heart attack Ex. Kidney or liver failure Ex. Cancer Ex. Asphyxiation Long list

10. Manner of Death 1.Natural 2.Homicide 3.Suicide 4.Accident 5.Undetermined

11. Jobs of the ME 1. ID the deceased 2. Time/date of death 3. Cause/manner 4. Protect property of dead 5. Notify next of kin

12. Estimating Time of Death 1. Rigor mortis 2. Livor mortis 3. Algor mortis 4. Stomach contents 5. Vitreous humor 6. Changes due to decomposition 7. Entomology 8. Botany

13. Rigor Mortis touch test Warm and not stiff: not more than a couple of hours Warm and stiff: dead between a couple of hours and a half day Cold and stiff: dead btw a half day and two days Cold and not stiff: dead more than two days

14. Rigor mortis ATP fuels muscle contraction- lack of ATP triggers rigor ATP breaks the link btw actin and myosin, ATP depleted after death, actin and myosin stay locked appears within 1-3 hour

15. Affects Rigor mortis –Body temperature and environmental temp. –Metabolic rate –Starvation –Physical activity –Poison

16. Cadaveric spasm Body or body part “Frozen” in position at time of death Fast rigor due to lack of ATP –struggle or chase –Exercise –Shooting a gun –“Death grip” during drowning

17. Timeline of Rigor Mortis appears within 1-3 hours 0-12 hours: Body stiffens, starting with jaw, neck, face/fingers/toes, trunk, arms, and legs 12-24 hours: Entire body stays rigid 24-36 hours: Relaxation starting with jaw, neck, face/fingers/toes, trunk, arms, legs

18. Livor mortis PML= postmortem lividity - Purple coloring - Blood settles closest to the ground - Appears within 30-60 min. of death - No discoloration if tight clothing Object pressing against body - Can tell if body has been moved since death

19. Problems with livor mortis Variations between races Blood loss Anemia

20. Other color changes Bluer color caused by being cyanotic (not enough O 2 ) –Can be caused by respiratory illness or cyanide poisoning Cherry red color- from carbon monoxide poisoning

21. Algor mortis - Drop in body temperature after death. - Avg. of 1-1.5 °F per hour - Measure in liver/rectum

22. Algor Mortis affected by »Location of body »Body size »Clothing »Weather »Temp @ death ex. Fever from illness ex. Elevated temp from drug use ex. Head injury

23. Rigor, livor, algor Only useful for 24-48 hours Rigor- body relaxes Livor- becomes fixed Algor- body reaches ambient temperature

24. Stomach contents If food is in the stomach, the degree of breakdown of the food can help provide an estimate of time of death. 90% of what we eat is out of the stomach in 2-3 hours

25. Decomposition A) Autolysis- softening/liquefying of the body caused by enzymes released by cell organelles after death. B) Bacterial- breaks tissue into liquids/gases

26. Stages of Bacterial Decomposition 1.Initial Decay 2.Putrefaction 3.Black Putrefaction 4.Butyric Fermentation 5.Dry Decay

27. 1. Initial Decay Initial Decay- externally OK, but internally decomposition starts. Discoloration of surface blood vessels in upper abdomen as bacteria spread. Color changes from red…dark red… purple…green

28. 1st sign- green over right lower abdomen –cecum-pouch at start of large intestine E.Coli bacteria are normally found in the body but are kept in check by the immune system. After death, the bacteria are no longer held in check and multiply rapidly.

29. E.Coli spreads from the intestines and enters the bloodstream. Bacteria form CO 2 : gas causes bloating and eventually rupture of intestines.

30. 2. Putrefaction Cadaver swollen w/ gases, odor of decay (within 2-3 days) Hair loosens Fluid from mouth and nose

31. Putrefaction Liver/brain—“swiss cheese” (from bubbling gases) Loose skin falls off Body swells, tongue/eyes protrude Breasts and genitalia balloon

32. 3. Black Putrefaction Flesh is soft w/ black areas. Strong odor

33. 4. Butyric fermentation cadaver drying out. –Some flesh. –Cheesy odor. –Ventral surface moldy. 5. Dry Decay

34. Vitreous humor Eye jelly dehydrates Potassium levels change Needle and syringe to suction the eye

35. Problems w/ vitreous humor –K+ levels vary from front to back – Need every drop of vitreous humor—can disrupt retina if pull to hard with syringe – Increased heat, humidity, fever… can falsely raise K levels –Variation between 2 people or between 2 eyes of the same person

36. Entomology After death, flies lay eggs on the body. The eggs develop into larvae (maggots), and then pupa, and then adults. The time it takes to progress through each stage is predictable, and can be used to determine when the eggs were first laid and thus, when the victim died

37. Tasks 1. Preautopsy meeting 2. Photos 3. Reexamination White light UV Laser Alternate light source Remove clothing, jewelry

38. Tasks 4. Fragile (trace) evidence Fibers Hairs Glass Debris 5. Vulnerable evidence collect saliva in bite marks take control sample near bite mark

39. Tasks 6.Swabs Vagina Penis Oral Anal Nasal

40. Tasks 7. x-rays Broken bones Metallic objects Healed fractures Dental x-rays 8. Gunshot residue 9. Scrape fingernails

41. Tasks 10. Wounds 11. Pubic Hair combing 12. Collect standard hairs Pulled from head Need 50-100 hairs 13. Casts Make 3-D casts of bite marks, entrance holes, cuts

42. Tasks 14. ID photos Face, tattoos, scars 15. Fingerprints 16. Autopsy A. Injection sites, look in orifices B. Y shaped incision C. Inspect organs »heart., lungs, liver, kidneys

43. Autopsies “This is the place where death rejoices to teach those who live.”