caissons disease

1. BY
Dr.Nafeeya
1st yr pg

2. Over view
 Definition
 Risk factors
 Pathogenesis
 Signs and symptoms
 Diagnosis
 Treatment
 Prevention
 Medicolegal importance

3. Definition
 Acute decompression syndrome (Caisson’s disease)
is an acute neurological emergency in divers.
 Also known as divers disease, bends,staggers,aeroembolic.
 Decompression sickness is a disorder in which nitrogen dissolved in the
blood and tissues by high pressure forms bubbles .
 It occurs most frequently during deep sea diving or flying in a non
pressurized aircraft or underwater construction worker.

5. Risk Factors
 Alcohol excess
 Cardiac defects-patent foramen ovale,ASD
 Cold water
 Dehydration
 Exertion
 Flying after diving
 Fatigue
 Hypoxia
 Increased pressure
 Length of time spent in pressurized environment
 Medications like-antihistamines,narcotics
 Obesity
 Older age
 Rapid ascent

6.  Effects of high partial pressure:
 At 100 feet –increased pressure is 4 times greater than surface.
 At 120 feet-mild narcosis will appears- lose his or her self care
 At 150-200 feet-drowsy
 At 200-250-strength decreasing significantly and divers feel clumsy
to perform the work
 Beyond 250 feet-divers almost useless as a result of nitrogen narcosis

7.  Henry's law is one of the gas laws states that: at
a constant temperature, the amount of a given gas
that dissolves in a given type and volume of liquid is
directly proportional to the partial pressure of that gas
in equilibrium with that liquid.

P=KH C
P-PARTIAL
PRESSURE OF
THE GAS IN
THE ATOMP
PRESSURE.
C-CONC OF
DISSSOLVED
GASES

8. Pathogenesis
 It is a particular form of gas embolism which occurs when indiviuals
are exposed to sudden lowering of pressure .
 When air is breathed under high pressure- increased amount of gas
become dissolved in the blood
 If the divers ascents suddenly ,bubbles of nitrogen gets formed.
 It causes –
 Bends-joints and skeletal pain
 Chokes-breathing problem
 Staggers-neurological problems

9. Symptoms – 1-6 hours
 Dizziness
 Double vision
 Headache
 Trouble to speak
 Pain in legs-joint pain
 Itching and rashes
Serious And Life-threatening Symptoms:
affecting the brain, spinal cord, inner ear,
and/or lung
Mild Symptoms: Arthralgia, Skin
Marbling, Small Patchy
Hemorrhages, And Lymphatic
Obstruction.

10. Frequency & onset
Symptoms Frequency
Local Joint Pain 89%
Arm Symptoms 70%
Leg Symptoms 30%
Dizziness 5.3%
Paralysis 2.3%
Shortness Of Breath 1.6%
Extreme Fatigue 1.3%
Collapse /unconscious 0.5%
Time to
onset
% of cases
Within 1
hour
42%
Within 3
hours
60%
Within 8
hours
83%
Within 24
hours
98%
Within 48
hours
100%

11. Diagnosis
1)X-ray and CT scan of whole body
2)Suspected venous embolism:
a)Abdomen opened first
b)Opening of the chest
c)PM demonstration of venous
embolism
d)Source of air - Air in SVC(stab wounds
of neck)
e)Composition of air - >95% nitrogen-
nitrogen narcosis

14. Treatment
 100% Hyperbaric oxygen
therapy followed by
 Recompression in a
hyperbaric chamber.
 Platelet inhibitors
 Anti-inflammatory drugs are
also useful.

15. Prevention
 To prevent the excess formation of bubbles leading to decompression
sickness, divers limit their ascent rate
 Dive and rise slowly in the water, and don't stay at your deepest depth
longer than recommended.
 Do not fly within 24 hours after diving.
 Don't drink alcohol before diving.
 Avoid hot tubs or hot baths after diving.
 Make sure you are well hydrated, well rested and prepared before you
scuba dive.

16. Region Autopsy findings
External examination cyanosis, cherry red coloration,marbling ,facial
edema,froth in mouth and nose,mottled pallor of
tongue ,abrasions ,contusions ..
Head and neck #,gas bubbles in cerebral arteries,vessels,
SDH,SAH,focal hge,cerebral edema
Eyes and ears Rupture of tympanic membrane,gas in retinal
vessels
Chest ,tracheobronchial tree,and lungs Foam,aspirated vomit,pneumothorax,pulmonary
edema,petechial hemorrhage,nitrogen bubbles in
pericapillary pulmonary arteries,fat emboli.
Blood from heart Air embolism,alcohol intoxication,CO .
Heart Air embolism ,IHD
Other organs Fatty change liver,infarction in many organs
Spinal cord Nitrogen bubbles in spinal arteries
Bones and joints Dysbaric osteonecrosis

18. PM DEMONSTRATION
1) Air in right ventricle
Sternum removed
Vessels clamped
Pericardium opened
Beaded appearance
Coronaries incised
2)Minus plunger
3)Pyrogallol test
AIR EMBOLISM

19. Pyrogallol Test
 RAPID AUTOPSY TEST
 Principle
1)putrifactive gases will not contain any o2
2)Alkaline solution turns purple
 Procedure
1)4ml freshly prepared 2%pyrogallol solution-2
syringes
2)1st syringe-add 4 drops of 0.5M NaOH – RV –
aspirate – seal -
shake – turns purple
3)2nd syringe – as control - turn brown in all cases

20. MEDICOLEGAL IMPORTANCE:
 Underwater Crime
 Scuba Deaths
 Underwater Disasters
 Underwater photograpny
 Recreational Diving Fatalities
 Forensic Biology
 Education Archives
 Cave Divers Unlock Mysteries
 Suicidal Inhalation

21. References
 Anil agarwal text book of forensic medicine
 Knights –forensic pathology
 Narayana reddy textbook of forensic medicine
 Dikishit textbook of forensic medicine
 Gautam Biswas-Review of forensic medicine and toxicology
 International Journal of Advanced Research (2016), Volume 4,
Issue 2, 25-30/6https://
 Journals.sagepub.com/doi/10.1177/0025817217734481
 July 2013 Journal of Forensic Sciences 58(5)
DOI: 10.1111/15564029.12239 Source PubMed
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