Campos J H
Department of Anesthesia, The University of Iowa College of Medicine, University of Iowa Hospitals and Clinics, Iowa City 52242-1079, USA.
Anesth Analg. 1997 Sep;85(3):583-6. doi: 10.1097/00000539-199709000-00018.
Hypoxemia is common during anesthesia with one-lung ventilation (OLV). This study tested the hypothesis that selective lobar blockade would result in higher PaO2 values compared with those found with total lung collapse independent of continuous positive airway pressure (CPAP) application. Thirty patients undergoing lobectomy were randomly assigned to one of four groups with the following maneuvers during OLV: Group 1 (n = 8) total lung collapse (TLC) plus 5 cm H2O of CPAP to the nonventilated operative lung for 15 mins, followed by selective lobe collapse plus 5 cm H2O of CPAP (during selective collapse only the surgical lobe was collapsed and the rest of that lung was ventilated); Group 2 (n = 6) selective lobar collapse plus 5 cm H2O of CPAP to the operative lung, followed by TLC plus 5 cm H2O of CPAP; Group 3 (n = 8) total lung collapse without CPAP, followed by selective lobe collapse and no CPAP; Group 4 (n = 8) selective lobe collapse without CPAP, followed by TLC and no CPAP. To obtain selective lobe collapse, the bronchial blocker of the Univent (Vitaid, Lewiston, NY) endotracheal tube was guided into the operative bronchus with the aid of a fiberoptic bronchoscope. Blood pressure, heart rate, and arterial blood gas measurements were obtained during the following times: Time 1--while the patient was awake; Time 2--two-lung ventilation (2LV) in the supine position; Time 3--after 30 min of OLV in the lateral decubitus position (no CPAP or selective blockade); Time 4 and Time 5--during maneuvers described above (see group description); Time 6--2LV resumed; Time 7--30 min after extubation. Twenty-eight patients completed the study. There were no differences among groups with regard to arterial blood pressure, heart rate, or arterial oxygen saturation during the experimental maneuvers. All four groups showed a decrease in PaO2 from 2LV to OLV (P < 0.05). Both with and without CPAP application, oxygenation was improved with selective lobe collapse compared with TLC. When selective lobe collapse with 5 cm H2O of CPAP followed TLC (group 1), PaO2 values increased to values similar to those found for 2LV (PaO2 449 +/- 122 vs 394 +/- 105 mm Hg). This study indicates that by using a bronchial blocker, changing from total lung collapse to selective lobar blockade improves PaO2 during lung surgery.
This study examines how oxygen tension in arterial blood can be higher during one-lung ventilation. The use of a bronchial blocker, which changes a total lung collapse to selective lobar blockade, improves oxygenation during lung surgery.
单肺通气（OLV）麻醉期间低氧血症很常见。本研究检验了以下假设：与全肺萎陷相比，选择性肺叶封堵在不应用持续气道正压通气（CPAP）的情况下可使动脉血氧分压（PaO2）值更高。30例行肺叶切除术的患者在OLV期间被随机分为四组，采用以下操作：第1组（n = 8）全肺萎陷（TLC）加5 cmH2O CPAP至非通气的术侧肺15分钟，随后选择性肺叶萎陷加5 cmH2O CPAP（在选择性萎陷期间仅手术肺叶萎陷，该肺其余部分通气）；第2组（n = 6）选择性肺叶萎陷加5 cmH2O CPAP至术侧肺，随后TLC加5 cmH2O CPAP；第3组（n = 8）全肺萎陷不应用CPAP，随后选择性肺叶萎陷且不应用CPAP；第4组（n = 8）选择性肺叶萎陷不应用CPAP，随后TLC且不应用CPAP。为实现选择性肺叶萎陷，在纤维支气管镜辅助下将Univent（Vitaid，纽约州刘易斯顿）气管导管的支气管封堵器置入术侧支气管。在以下时间点测量血压、心率和动脉血气：时间1——患者清醒时；时间2——仰卧位双肺通气（2LV）时；时间3——侧卧位OLV 30分钟后（不应用CPAP或选择性封堵）；时间4和时间5——在上述操作期间（见分组描述）；时间6——恢复2LV；时间7——拔管后30分钟。28例患者完成研究。在实验操作期间，各组在动脉血压、心率或动脉血氧饱和度方面无差异。所有四组从2LV到OLV时PaO2均下降（P < 0.05）。无论是否应用CPAP，与TLC相比，选择性肺叶萎陷时氧合均得到改善。当TLC后采用5 cmH2O CPAP的选择性肺叶萎陷（第1组）时，PaO2值升高至与2LV时相似的值（PaO2 449±122 vs 394±105 mmHg）。本研究表明，在肺手术中，通过使用支气管封堵器，从全肺萎陷转变为选择性肺叶封堵可提高PaO2。
本研究探讨了单肺通气期间动脉血氧张力如何能够更高。使用支气管封堵器将全肺萎陷转变为选择性肺叶封堵可改善肺手术期间的氧合。
