Friday, May 12, 2006

Hyperbaric oxygen in CO poisoning

Saturday May 13, 2006
Hyperbaric oxygen in CO poisoning

Q; What is the role of hyberbaric oxygen in the management of lethal Carbon-monoxide (CO) poisoning ?

A; It decreases the half life of CO from 5 hours to half hour and so the possible complications. It prevents lipid peroxidation in the brain and preserve ATP levels in tissue exposed to carbon monoxide. It has shown to decrease the cognitive sequelae by 46 % when compared with 'normobaric' group at 6 weeks 2.

Limitations: Hyperbaric oxygen in CO poisoning has its own limitations. It may induce "hyperoxic"
seizures (rare) 3. Other adverse effects of hyperbaric oxygen includes reversible myopia, rupture of the middle ear, barotrauma to lungs 4. Hyperbaric oxygen should be reserved for lethal cases of CO poisoning.

Alternate: If hyperbaric oxygen is not available, apply 100% oxygen, high PEEP and if needed high-frequency ventilation. 100% O2 reduces half life of CO effectively to about one and half hour.

Reference: (click to get abstract)
1.
Diagnosis and treatment of carbon monoxide poisoning - Respir Care Clin N Am. 1999 Jun;5(2):183-202.
2.
Hyperbaric Oxygen for Acute Carbon Monoxide Poisoning - Volume 347:1057-1067, oct. 3, 2002
3. Central nervous system oxygen toxicity during hyperbaric treatment of patients with carbon monoxide poisoning - Hampson NB, Simonson SG, Kramer CC, Piantadosi CA - UNDERSEA & HYPERBARIC MEDICINE 23 (4): 215-219 DEC 1996
4.
Hyperbaric-Oxygen Therapy - Volume 334:1642-1648, june 20, 1996