Nitric oxide gives maximal response after coronary artery bypass surgery.
The dose-response to inhalation of nitric oxide (NO) after coronary artery bypass surgery was studied in seven patients with normal preoperative lung function and chest radiograms. During postoperative controlled ventilation with PEEP 5 and 10 cmH2O, the patients inhaled NO in concentrations of 2 to 25 ppm, in random order, for 6 to 10 minutes. Hemodynamic and oximetric data were analyzed before, 5 minutes after start of the NO inhalation, and 5 minutes after the cessation. The response was the same at all concentrations; mean pulmonary artery pressure decreased by 11 +/- 1% (P < 0.05) and pulmonary vascular resistance decreased by 22 +/- 2% (P < 0.05). Systemic hemodynamics did not change, but oximetric parameters tended to improve. Changes in PEEP did not affect the response. It is concluded that, in patients who have undergone coronary artery bypass grafting, inhalation of 2 to 25 ppm NO causes a dose-independent decrease in pulmonary artery pressure and pulmonary vascular resistance. In order to investigate the dose-response curve, concentrations lower than 2 ppm of NO must be used.
Lindberg
L
L
Department of Anesthesiology and Intensive Care, University Hospital of Lund, Sweden.
Larsson
A
A
Steen
S
S
Olsson
S G
SG
Nordström
L
L
D000368:Aged; D001794:Blood Pressure / Q000187:drug effects; D002302:Cardiac Output / Q000187:drug effects; D002306:Cardiac Volume / Q000187:drug effects; D001026:Coronary Artery Bypass; D004305:Dose-Response Relationship, Drug; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009569:Nitric Oxide / Q000008:administration & dosage* / Q000494:pharmacology*; D010100:Oxygen / Q000097:blood; D010101:Oxygen Consumption / Q000187:drug effects; D011651:Pulmonary Artery / Q000187:drug effects; D013318:Stroke Volume / Q000187:drug effects; D014655:Vascular Resistance / Q000187:drug effects; D016277:Ventricular Function, Left / Q000187:drug effects; D016278:Ventricular Function, Right / Q000187:drug effects
D009569:Nitric Oxide; D010100:Oxygen