Comparison of pulmonary gas exchange according to intraoperative ventilation modes for mitral valve repair surgery via thoracotomy with one-lung ventilation: a randomized controlled trial.
OBJECTIVE
Impaired pulmonary gas exchange after cardiac surgeries with cardiopulmonary bypass (CPB) often occurs, and the selection of mechanical ventilation mode, pressure-controlled ventilation (PCV) or volume-controlled ventilation (VCV), may be important for preventing hypoxia and improving oxygenation. The authors hypothesized that patients with PCV would show better oxygenation, compared with VCV, during one-lung ventilation (OLV) for mitral valve repair surgery (MVP) via thoracotomy.


METHODS
Randomized controlled trial.


METHODS
University teaching hospital.


METHODS
Sixty patients in each group.


METHODS
MVP was performed using thoracotomy with OLV by PCV or VCV.


RESULTS
Arterial partial pressure of oxygen (PaO2) and fraction of inspired oxygen (FIO2) were measured before anesthesia induction (T0), at skin incision (T1), after administration of heparin (T2), at 30 minutes after CPB weaning (T3), just before departure from the operating room to the intensive care unit (ICU) (T4), and 1 hour after ICU admission (T5), and PaO2/FIO2 ratio was calculated. Peak inspiratory pressure (PIP) and mean inspiratory pressure (Pmean) were recorded at T1, T2, T3, and T4. No significant difference was noted in the PaO2/FIO2 ratio between the groups at any measured point. PIP in the PCV group at all measured points was lower than that in the VCV group (T1, p<0.001; T2, p<0.001; T3, p<0.001; T4, p=0.025, respectively). Pmean was not different between the two groups at any measured point.


CONCLUSIONS
PCV during OLV in patients undergoing MVP via a thoracotomy with OLV showed lower PIP compared with VCV, but this did not improve pulmonary gas exchange.
Department of Anaesthesiology and Pain Medicine, Konkuk University Hospital, Konkuk University Medical Center; Research Institute of Medical Science, Konkuk University School of Medicine, Seoul, Korea.
Woon-Seok
WS
Kang
Department of Anaesthesiology and Pain Medicine, Konkuk University Hospital, Konkuk University Medical Center; Research Institute of Medical Science, Konkuk University School of Medicine, Seoul, Korea. Electronic address: yshkim75@daum.net.
Seong-Hyop
SH
Kim
Department of Thoracic and Cardiovascular Surgery, Cleveland Clinic, Cleveland, Ohio.
Jin Woo
JW
Chung
D000328:Adult; D005260:Female; D006349:Heart Valve Diseases / Q000503:physiopathology / Q000601:surgery*; D019918:Heart Valve Prosthesis Implantation / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000601:surgery*; D016343:Monitoring, Intraoperative; D061810:One-Lung Ventilation / Q000379:methods*; D010313:Partial Pressure; D011175:Positive-Pressure Respiration / Q000379:methods*; D011659:Pulmonary Gas Exchange / Q000502:physiology*; D012189:Retrospective Studies; D013908:Thoracotomy / Q000379:methods*
cardiac anesthesia; one-lung ventilation; pressure-controlled ventilation; volume-controlled ventilation