Inhaled nitric oxide reverses cell-free hemoglobin-induced pulmonary hypertension and decreased lung compliance. Preliminary results.
BACKGROUND: In order to test the hypothesis that inhaled nitric oxide (NO) reverses the pulmonary hypertension induced by alphaalpha-diaspirin crosslinked hemoglobin (alphaalphaHb), were studied anesthetized pigs that were administered with a total dose of 200 mg/kg of 10% alphaalphaHb. Inhaled NO (5 ppm) was administered for 10 min, and then discontinued for 10 min. This cycle was then repeated with 10 ppm inhaled NO. RESULTS: alphaalphaHb caused pulmonary arterial pressure (PAP) to increase from 27 +/- 1.7 to 40 +/- 3.0 mmHg (P<0.05) and dynamic lung compliance to decrease from 29+/- 1.5 to 23+/- 1.6 ml/cmH2O (P < 0.05). After both doses of inhaled NO, but particularly 10 ppm, PAP was reduced (P < 0.05) and lung compliance increased (P < 0.05) from the alphaalphaHb levels. When inhaled NO was discontinued PAP again increased and lung compliance decreased to levels significantly different from baseline (P < 0.05). CONCLUSION: We conclude that cell-free hemoglobin-induced pulmonary hypertension and decreased lung compliance can be selectively counteracted by inhaled NO.
Figueiredo
LF
Department of Cardiopneumology, DEX-Instituto do Coração, Faculdade do Medicina, Universidade de São Paulo, SP, Brazil. expluiz@incor4.incro.usp.br
Mathru
M
Jones
JR
Solanki
D
Kramer
GC