Description

ABSTRACT

Van Meter KW. Severe Anemia. Undersea Hyperb Med. 2026 First Quarter; 53(1):199-208.

Hyperbaric oxygen (HBO2) therapy serves as a critical bridge treatment for severe anemia when red

blood cell transfusion is not possible due to religious objection, crossmatch incompatibility, or blood

unavailability. Hemoglobin levels below 3.6 g/dL are clearly inadequate for tissue oxygenation, and

accumulative oxygen debt exceeding 33 L/m2 within four hours of severe hemorrhage is unsurvivable.

HBO2 administered at pressures of 2 to 3 ATA dissolves sufficient oxygen directly in plasma to compensate

for the deficit in hemoglobin-bound oxygen-carrying capacity, while concurrent use of hematinics

and erythropoietin-stimulating strategies supports endogenous red blood cell regeneration during

surface intervals between treatments. Controlled animal studies spanning from 1943 through the

1990s consistently demonstrate improved survival in HBO2-treated groups compared to normobaric air

controls across multiple hemorrhagic shock models; human case reports, case series, and one controlled

prospective trial in post-hepatectomy patients further support clinical efficacy. Classified as an AHA

Class IIb indication with long-standing CMS approval, HBO2 carries a cost comparable to a single unit

of packed red blood cells and maintains a favorable safety profile with few and infrequent side effects.

These findings position HBO2 as a practical, low-technology, cost-competitive intervention for reducing

accumulated oxygen debt in critically anemic patients across settings including emergency departments,

operative units, and intensive care environments.