Effect of hyperoxia on vascular endothelial growth factor levels in a wound model

Hypothesis: Hyperbaric oxygen (HBO) therapy increases vascular endothelial growth factor (VEGF) levels in wounds. Design: Wounds were monitored fur oxygen delivery during HBO treatment, and wound fluids were analyzed fur VEGF and lactate oil days 2, 5, and 10 foll owing wounding. Setting: Experimental animal model. Interventions: Rats were randomized to HBO therapy and control groups. The HBO therapy was administered for 90 minutes, twice daily with 100% oxygen a t 2.1 atmospheres absolute. Treatment was administered for 7 days following wounding. Main Outcome Measures: Vascular endothelial growth factor, POL, and lactate levels in wound fluid were measured on days 2, 5, and 10. Results: Wound oxygen rises with HBO from nearly 0 mm Hg to as high as 600 mm Hg. The peak level occurs at the end of the 90-minute treatment, and hyp eroxia of lessening degree persists for approximately 1 hour. The VEGF leve ls significantly increase with HBO by approximately 40% 5 days following wo unding and decrease to control levels 3 days after exposures are stopped. W ound lactate levels remain unchanged with HBO treatment (range, 2.0-10.5 mm ol/L). Conclusions: Increased VEGF production seems to explain in part the angioge nic action of HBO. This supports other data that hypoxia is not necessarily a requirement for wound VEGF production.