Barotraumas- Diving and Hyperbaric Medicine.pptx

This is the Presentation on barotraumas experienced in Divers and patients undergoing Hyperbaric Oxygen therapy.

1. BAROTRAUMAS

2. Introduction Tissue damage caused by expansion or contraction of enclosed gas spaces due to pressure changes Resultant tissue distortion Maximum near surface

3. Variants Pulmonary Aural Sinus Dental Gastro-intestinal Equipment

4. Variants Miscellaneous Localized surgical emphysema Pneumoperitoneum Pneumocephalous Bone cyst barotrauma Cranial nerve palsies Others

5. Pulmonary Barotrauma Pulmonary barotrauma of ascent is the most serious of barotraumas Clinical manifestation of Boyles law Also called “burst lung” or pulmonary over inflation Commonly seen in divers & submariners

6. Pathophysiology All gas obeys Boyle’s law The lung tends to stretch against an increasing resistance May involve whole of the lung May involve only localized areas

7. Pathophysiology Generalized pulmonary barotrauma When the ambient pressure changes by 70 mm hg or more An ascent from a depth of about 1 mts to the surface

8. Pathophysiology Scarring within lung parenchyma An increased risk Site of injury may be different from the site of scar

9. Predisposing factors Disorders that may result in Local compliance changes Gas trapping Airway obstruction

10. Predisposing factors Previous spontaneous pneumothorax Asthma/ Sarcoidosis Cysts/ tumors Pleural adhesions Intrapulmonary fibrosis Infection & inflammation

11. Precipitating factors Inadequate exhalation caused by Panic Faulty apparatus Water inhalation

12. Precipitating factors Reduction of compliance at maximum inspiratory pressures The lungs become less distensible & are exposed to more stress than normal lung Lower then normal forced vital capacity

13. Manifestations Pulmonary tissue damage Mediastinal emphysema Pneumothorax Air embolism

14. Symptoms Pulmonary tissue damage Explosive exhalation on surfacing A high pitched cry Symptoms Dyspnoea Cough Haemoptysis If wide spread death can occur

15. Symptoms Mediastinal emphysema Voice change Feeling of fullness in throat Dysponea Dysphagia Retrosternal discomfort Syncope Shock or unconciousness

16. Symptoms Pneumothorax Rupture of the visceral pleura Air enters the pleural cavity Expands during further ascent unilateral / bilateral Retrosternal or unilateral chest pain Dysponea Increased respiratory rate

17. Clinical signs Pneumothorax Diminished breath sounds Hyper-resonance Tracheal shift Shift of apex beat Under pressure becomes a tension pneumothorax during ascent

18. Symptoms Air embolism Gas into the pulmonary veins Then into the systemic circulation Vascular damage/ obstruction Leading to Hypoxia Infarction Activation of inflammatory cascade

19. Symptoms Air embolism Loss of conciousness Confusion Aphasia Paresthesia or sensory disturbance Vertigo/ Convulsions Visual disturbances Cardiac type chest pain Skin marbling

20. Aggravating factors Further ascent in chamber/ underwater Ascent to altitude during air transport Physical exertion Increased respiratory activity Breathing against resistance Coughing & valsalva maneuver

21. Treatment Pulmonary tissue damage 100% oxygen Positive pressure ventilation if required Electrolyte & fluid balance

22. Treatment Mediastinal emphysema Asymptomatic patient Observation & rest Mild symptoms 100% oxygen Severe symptoms Therapeutic recompression with oxygen

23. Treatment Pneumothorax Mild cases 100% oxygen Severe cases Aspiration / intercostal catheter Therapeutic recompression if required

24. Treatment Air embolism Positioning – Nurse in a horizontal position 100% oxygen Recompression

25. Prevention Increased standards of fitness for divers Modification of fitness & diving techniques Development of safer equipments Avoid diving after any incident of pulmonary barotrauma Do not hold breath while ascent or descent

26. Pulmonary barotrauma of descent Very rare Occurs during Breath hold diving Loss of surface pressure supply Failure or absence of a non return valve Failure of gas supply to compensate for the rate of descent

27. Pulmonary barotrauma of descent Clinical feature Chest pain Haemoptysis Haemorrhagic pulmonary oedema Treatment IPPV with oxygen Fluid maintenance

28. EAR IN DIVING

29. Anatomy of ear External ear Tympanic membrane Middle ear cleft Ossicles Mastoid process Inner ear

30. Anatomy

31. Ear Barotrauma Two types Barotrauma of Descent Barotrauma of Ascent Can affect External ear Middle ear Inner ear USMD

32. Barotrauma of Descent Failure or an inability to equalize pressures Space taken up by engorgement Mucous membrane Edema Haemorrhage Commonly called “squeeze”

33. Middle ear barotrauma of descent Most common disorder in diver Eustachian Tube Closed in normal condition Open when the pressure gradient between pharynx and middle ear reach 10 – 30 mm of Hg or 13-39 cm of water USMD

34. Middle ear barotrauma of descent Achieved by Yawning Movements of jaw Swallowing USMD

35. Causes Pathology of the upper respiratory tract obstructing eustachian tube Incorrect autoinflation technique USMD

36. Eustachian tube block Common cold Nasal allergy Nasal polyps DNS Irritants Alcohol ingestion USMD

37. Incorrect technique Not clearing at surface Delay in clearing during descent Descent to the point of ‘locking’ Head- down or horizontal position Not clearing at bottom Not clearing during ascent Repeated yo-yo dives USMD

38. Classification GRADE 0 Symptoms without signs USMD

39. Classification GRADE I Injection of tympanic membrane along HOM USMD

40. Classification GRADE II Injection, h’age within tympanic membrane USMD

41. Classification GRADE III Gross haemorrhage USMD

42. Classification GRADE IV Free blood in the middle ear Blueness and bulging USMD

43. Classification GRADE V Tympanic membrane perforation

44. Clinical features 20 mmHg -- Sensation of heaviness 150 mmHg -- Pain 100-760 mmHg -- TM rupture (pain resolved; bleeding) Water in middle – Nausea, vertigo ear Epistaxis During ascent -- Mild conductive deafness

45. Treatment Avoid diving, autoinflation until resolution Systemic/local decongestant Antibiotic in gross haemorrhage or perforation USMD

46. Prevention Autoinflation prior to dive Autoinflation as soon as the pressure is felt Not to attempt autoinflate while horizontal and head down position Do not use multiple ascent (yo-yo diving) USMD

47. Prevention Auto inflate every 1 meter of a descent, use a descent line Auto inflate with head upright Avoid diving with problems

48. Middle ear auto-inflation techniques Valsalva manoeuvre Pinch nose, close mouth, exhale Frenzel manoeuvre Close mouth & nose, elevate tongue as a piston Toynbee manoeuvre Swallow with mouth & nose closed

49. Middle ear auto-inflation techniques Lowry technique Valsalva + Toynbee Hold nose, blow & swallow Edmonds technique No. 1 : Rock jaw fwd & down + Valsalva No. 2 : Close nose & mouth, suck cheeks in, puff them out quickly

50. Middle ear auto-inflation techniques BTV technique Voluntary opening of ET Roydhouse technique Raise uvula, move back of tongue downwards

51. External ear barotrauma of descent External ear squeeze or reversed ear Occlusion of external ear by Wax, tight hood, mask strap, ear plug, exostosis

52. External ear barotrauma of descent Contraction of air space is compensated by Tissue damage Outward bulging of tympanic membrane Congestion and haemorrhage of tympanic membrane

53. Clinical features Mild to moderate pain On ascent Pain and bloody discharge Perforation is usually rare Petechial hemorrhage in the auditory canal and blood filled cutaneous bleb may extend to TM

54. Inner ear barotrauma Predisposing factors Ear barotrauma of any type Difficulty in autoinflation Excessive force to autoinflation Increased intracranial pressure

55. Inner ear barotrauma Combined cochlear and vestibular-50 % Cochlear – 40% Vestibular- 10 % Shallow diving - 2 mts can cause IEBT

56. Pathophysiology Periylmph fistula Rupture of Round window Rupture of Oval window Membrane rupture with in the labyrinth

57. Inner ear barotrauma Clinical features Sensation of blockage of ear Tinnitus Vestibular disturbances Hearing loss Associated middle ear barotrauma Once trauma –recurrence is more USMD

58. Management Investigations Daily audiometry up to 8000 HZ Positional nystagmography Caloric test when TM is intact Positional audiometry for perilymph fistula USMD

59. Management Treatment Avoid increase CSF pressure Avoid loud noise Symptomatic treatment No improvement in 24 hr-operative intervention Exploratory tympanotomy and proceed

60. Prevention Autoinflation prior to dive Autoinflation as soon as the pressure is felt Not to attempt autoinflate while horizontal and head down position Do not use multiple ascent (yo-yo diving) Avoid diving with problems

61. Barotrauma of ascent Increased volume of gas because of decrease of pressure in a closed cavity Distension of tissue around the expanding gas Rupture of tympanic membrane can occur resulting bleeding ear

62. Middle ear barotrauma of ascent Symptoms Pressure sensation, pain Mild vertigo Hearing loss

63. Middle ear barotrauma of ascent Treatment Prohibition of diving Antibiotic Decongestant Prevention Training in correct auto inflation tech

64. Sinus barotrauma Injury due to change of volume of the gas spaces within the paranasal sinuses Pathological changes Mucosal detachment Sub-mucosal hematoma Blood clots in membranous sac Small haemorrhages Swelling of mucosal membranes

65. Sinus Barotrauma of Descent(Squeeze) Blockage of ostium predisposed by Sinusitis with mucosal hypertrophy/ congestion Rhinitis Redundant mucosal folds Nasal polyps

66. Sinus Barotrauma of Descent(Squeeze) Symptoms Sensation of tightness/ pressure Pain Dull ache Extrusion of blood and mucous on ascent

67. Sinus Barotrauma of Descent(Squeeze) Prevention Refrain diving URTI Sinusitis Rhinitis

68. Sinus Barotrauma of Descent(Squeeze) Prevention Cessation of smoking Avoidance of allergens ( steriod sprays) Correction of nasal abnormalities Positive pressure techniques Feet first descents

69. Sinus Barotrauma of Ascent Occlusion of sinuses by Mucosal congestion Folds or sinus polyps Pain +/ - Aggravates by rapid ascent Free ascent training Emergency ascent Submarine escape

70. Sinus Barotrauma of Ascent Manifestations Fracture of wall and track Surgical emphysema Rupture of air cells Symptoms Sharp /sudden pain

71. Sinus Barotrauma of Ascent Treatment Spontaneous resolution Suspension of diving Treatment of underlying condition HBOT in doubtful cases

72. Dental Barotrauma Areodontalgia Tooth caries Old divers Prevention Biannual dental checks X-ray Avoid diving after extraction Slow descent and ascent

73. Dental Barotrauma Treatment Analgesia Dental repair Other associated disorder

74. Gastrointestinal Barotrauma Inexperienced diver Aerophagia Valsalva (head down) Carbonated beverages Heavy meals Treatment Slow/ stop ascent Release tight fittings Recompression

75. Equipment Barotrauma Mask squeeze (Facial) Suit squeeze (Skin) Divers squeeze (head & body)