[Effect of combination of nitric oxide inhalation and inverse ratio ventilation in endotoxin-induced acute respiratory distress syndrome in sheep].
OBJECTIVE
To observe the effect of combination of nitric oxide (NO) inhalation and inverse ratio ventilation (IRV) on oxygenation and hemodynamics in endotoxin-induced acute respiratory distress syndrome (ARDS) in sheep.


METHODS
Sheep ARDS model was induced by an intravenous infusion of low dose endotoxin, and then animals were randomly divided into two groups. (1) NO group (n=6), inhalation of 40x10(-6) nitric oxide. (2) Combination group (n=6), receiving mechanical ventilation with IRV (inspiratory-to-expiratory ratio of 2:1) and inhalation of 40x10(-6) NO. The dynamic changes in gas exchange and hemodynamics were measured with the aid of Swan-Ganz catheter and arterial blood gas analysis before and after the onset of, ARDS and 30 minutes after treatment.


RESULTS
The combination of IRV and 40x10(-6) NO inhalation rapidly reduced mean pulmonary arterial pressure (MPAP), increased PaO(2), decreased P((A-a))O(2), and Qs/Qt without inducing significant change in systemic hemodynamics, and it was a more effective method of correcting hypoxemia than inhalation of nitric oxide alone. NO inhalation did not change the airway pressure of the model, but the combined treatment resulted in reduction of peak inspiratory pressure and increase of mean airway pressure.


CONCLUSIONS
The combined use of IRV and NO inhalation has an additive effect on improving oxygenation in endotoxin-induced acute respiratory distress syndrome in sheep.
Liu
Shao-hua
SH
The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, Jiangsu, China.
Xu
Xin-rong
XR
Xu
Ji
J
Zuo
Xiang-rong
XR
Qin
Ping-ping
PP
D000280:Administration, Inhalation; D000818:Animals; D001784:Blood Gas Analysis; D003131:Combined Modality Therapy; D004731:Endotoxins / Q000008:administration & dosage / Q000633:toxicity; D005260:Female; D008171:Lung Diseases / Q000097:blood / Q000209:etiology / Q000628:therapy*; D008297:Male; D009569:Nitric Oxide / Q000008:administration & dosage / Q000627:therapeutic use*; D011175:Positive-Pressure Respiration / Q000379:methods*; D011659:Pulmonary Gas Exchange / Q000187:drug effects; D011669:Pulmonary Wedge Pressure / Q000187:drug effects; D012756:Sheep; D016896:Treatment Outcome
D004731:Endotoxins; D009569:Nitric Oxide