What types of patients are treated with hyperbaric oxygen therapy?

1. Deep sea diving patients with decompression sickness
2. Those with thermal injuries
3. Patients with carbon monoxide poisoning
4. Those with refractory osteomyelitis
a. 1, 2, and 3 c. 2, 3, and 4
b. 1, 2, and 4 d. 1, 2, 3, and 4

ANS: D
Decompression sickness arises from the generation of nitrogen bubbles in the vascular system and tissues in volumes sufficient to interfere with the function of an organ. The cause of gas bubble formation is the rapid decompression during ascent from diving when the speed of decompres-sion exceeds the ability of the gas-saturated tissues to vent the gases by simple diffusion. For this type of patient, hyperbaric oxygen will reduce the size of the bubbles. For thermal injuries, hy-perbaric oxygen limits the progression of the burn injury, reduces swelling, and may reduce the need for surgical intervention. For CO poisoning, hyperbaric oxygen promotes the dissociation of carboxyhemoglobin more than just oxygen alone. For refractory osteomyelitis, hyperbaric oxygen provides periodic elevation of bone and tissue oxygen tension from hypoxic levels to normal or supranormal levels, which promotes collagen production by fibroblasts.