I. Mayers et al., AUGMENTATION OF HYPOXIC PULMONARY VASOCONSTRICTION BY N-G-L-METHYL-ARGININE IN A RABBIT MODEL OF THERMAL-INJURY, The American journal of emergency medicine, 14(7), 1996, pp. 629-634
We tested deeply anesthetized rabbits to determine if a burn acutely d
iminished the strength of hypoxic pulmonary vasoconstriction (HPV) and
if this could be augmented by L-NMMA, a nitric oxide synthase inhibit
or, We induced a burn using water heated to 75 degrees C and assessed
the strength of HPV as the difference in pulmonary vascular resistance
during 100% and 13% O-2 ventilation. The rabbits then were randomized
to receive 10 mg/kg L-NMMA (n = 8) or a placebo (n = 8). The strength
of HPV decreased from 0.42 +/- 0.11 mm Hg/mL/min preburn to 0.22 +/-
0.11 mm Hg/mL/min postburn (P < .05). L-NMMA administration augmented
HPV to a postburn value of 0.48 +/- 0.014 mm Hg/mL/min (P < .05). We s
peculate that the loss of HPV following a burn could worsen ventilatio
n to perfusion mismatch and thereby aggravate the hypoxia associated w
ith burns, Augmentation of HPV might be a short term goal during the a
cute stabilization of hypoxic burn patients. Copyright (C) 1996 by W.B
. Saunders Company