[A comparison of the effects of 50 % oxygen combined with CPAP to the non-ventilated lung vs. 100 % oxygen on oxygenation during one-lung ventilation].
OBJECTIVE
In a prospective, randomised, double-blind study the effects of FiO (2) of 0,5 with CPAP and a FiO (2) of 1.0 without CPAP on oxygenation and pulmonary shunt during one-lung ventilation (OLV) were examined.


METHODS
In 20 patients undergoing thoracotomy (ASA II/III) two sequential ventilation methods were used during OLV: a) FiO (2) of 1.0 (OLV-100) and b) a FiO (2) of 0.5 in N (2)O combined with CPAP of 5 cm H (2)O to the non-ventilated lung (OLV-CPAP), whereby the sequence in 10 patients was OLV-CPAP followed by OLV-100; and the opposite in the remaining 10 patients. Operating conditions were graded by the surgeon.


RESULTS
OLV-CPAP was associated with a better oxygenation and a lower shunt compared to OLV-100 (paO (2) : 198 +/- 40 mmHg vs 181 +/- 38 mmHg; p < 0.05 and Qs/Qt: 30 +/- 6 % vs. 34 +/- 8 %; p < 0.01, respectively). The different sequence of the ventilation methods did not cause significant differences in the results. The surgical conditions were not impaired by the CPAP of 5 cm H (2)O.


CONCLUSIONS
The application of low FiO (2) with CPAP provided a better oxygenation and a lower pulmonary shunt during the OLV compared to high FiO (2) without CPAP.
Sentürk
M
M
Abteilung für Anästhesiologie, Istanbul Universität, Medizinische Fakultät, Istanbul. merthasta@yahoo.com
Layer
M
M
Pembeci
K
K
Toker
A
A
Akpir
K
K
Wiedemann
K
K
D000368:Aged; D018685:Anesthetics, Inhalation; D045422:Continuous Positive Airway Pressure; D004311:Double-Blind Method; D005260:Female; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D000860:Hypoxia / Q000097:blood; D008297:Male; D008875:Middle Aged; D009609:Nitrous Oxide; D010100:Oxygen / Q000097:blood*; D010102:Oxygen Inhalation Therapy; D010366:Peak Expiratory Flow Rate; D011175:Positive-Pressure Respiration; D012121:Respiration, Artificial; D012129:Respiratory Function Tests; D013908:Thoracotomy
D018685:Anesthetics, Inhalation; D009609:Nitrous Oxide; D010100:Oxygen