Inhaled nitric oxide administration during one-lung ventilation in patients undergoing thoracic surgery.
OBJECTIVE
To evaluate the effects of inhaled nitric oxide (iNO) on hemodynamics and oxygenation during one-lung ventilation (OLV) in the lateral decubitus position in patients undergoing elective thoracic surgery.


METHODS
Prospective study.


METHODS
University hospital.


METHODS
Thirty consecutive patients scheduled for thoracotomy.


METHODS
Anesthesia consisted of thoracic epidural analgesia combined with general anesthesia (isoflurane, fentanyl, and vecuronium bromide). Systemic and pulmonary circulations were monitored with a radial artery catheter and a pulmonary artery catheter. Inhaled NO, 40 ppm, was administered during OLV, and the inhaled gas mixture was monitored for NO and nitrogen dioxide (NO2). Hemodynamic and oxygenation data were collected before and during inhaled NO administration.


RESULTS
Inhaled NO caused a reduction of pulmonary vascular resistance index from 249 +/- 97.6 dyne. sec. cm(-5) to 199.3 +/- 68.9 dyne. sec. cm(-5) (p < 0.05), without effects on systemic hemodynamics or impairment of oxygenation. A stratification of the patients according to values of QS/QT (< 30%, 30% to 44%, > or = 45%), PaO(2)/fraction of inspired oxygen (> or = 200, 100 to 199, < 100), and pulmonary hypertension (mean pulmonary arterial pressure < 24 or > or = 24 mmHg) showed that inhaled NO causes a significant reduction of mean pulmonary artery pressure in patients with pulmonary hypertension, mainly as a result of a reduction of pulmonary vascular resistance index, and improves oxygenation by reducing intrapulmonary shunt in patients with severe hypoxemia during OLV.


CONCLUSIONS
Inhaled NO administration neither significantly decreased mean pulmonary arterial pressure in patients with normal pulmonary artery pressure nor improved oxygenation in nonhypoxic patients. Nevertheless, inhaled NO is effective in patients with pulmonary hypertension and hypoxemia during OLV.
Rocca
G D
GD
Istituto di Anestesiologia e Rianimazione, Cattedra di Chirurgia Toracica, University of Rome La Sapienza, Azienda Ospedaliera Policlinico Umberto I, Rome, Italy. Dellarocca@uniroma1.it
Passariello
M
M
Coccia
C
C
Costa
M G
MG
Di Marco
P
P
Venuta
F
F
Rendina
E A
EA
Pietropaoli
P
P
D000368:Aged; D000769:Anesthesia, Inhalation; D001794:Blood Pressure / Q000187:drug effects; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D000860:Hypoxia / Q000097:blood; D008297:Male; D008875:Middle Aged; D009569:Nitric Oxide; D010101:Oxygen Consumption / Q000187:drug effects; D011446:Prospective Studies; D011651:Pulmonary Artery / Q000502:physiology; D011652:Pulmonary Circulation / Q000187:drug effects; D012121:Respiration, Artificial; D019616:Thoracic Surgical Procedures
D009569:Nitric Oxide