caissons disease

caissons disease

1. CAISSON’S DISEASE BY Dr.Nafeeya 1 st 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.

4. 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

5. 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

6. 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

7. 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

8. 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.

9. 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%

10. 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

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

12. 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 alcoho l before diving. Avoid hot tubs or hot baths after diving. Make sure you are well hydrated, well rested and prepared before you scuba dive.

13. 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

14. 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

15. 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)1 st syringe-add 4 drops of 0.5M NaOH – RV – aspirate – seal - shake – turns purple 3)2 nd syringe – as control - turn brown in all cases

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

17. 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