Symreng T, Gomez M N, Johnson B, Rossi N P, Chiang C K
Department of Anesthesia, University of Iowa Hospitals and Clinics, Iowa City 52242.
J Cardiothorac Anesth. 1989 Apr;3(2):139-43. doi: 10.1016/s0888-6296(89)92258-8.
The authors evaluated the incidence and type of technical problems associated with blind insertion of intrapleural catheters placed in 21 anesthetized patients and then injected in a double-blind fashion with 0.5% bupivacaine (1.5 mg/kg) or isotonic saline. The patients' chests were then opened, catheter positions located, and the lungs inspected. Eleven of the catheters were located with the tips intrapleurally, three extrapleurally, and seven actually in lung tissue. Eight patients had holes in the lung surface. Three patients had a pneumothorax, two of which were under tension. Plasma bupivacaine levels reached maximal concentrations at about 20 minutes in those with intrapleurally placed catheters, but not until 60 minutes when the catheter had actually penetrated the lung. Significant variations in plasma bupivacaine levels were achieved when the catheter entered lung tissue, with potentially toxic levels in one patient. To evaluate intraoperative analgesic effects, all patients were given a standard anesthetic with isoflurane, oxygen, and a muscle relaxant. There was no significant difference in isoflurane requirement between the groups who had bupivacaine v saline injected into their intrapleural catheters before surgery. It is concluded that blind insertion of intrapleural catheters can be hazardous, especially if followed by positive-pressure ventilation. In addition, catheter placement in lung tissue, which was not uncommon, delays the time for peak plasma concentrations and may increase risk of toxicity. Intrapleural bupivacaine was not found to be a useful adjunct to general anesthesia during thoracotomies.
作者评估了21例麻醉患者盲插胸膜内导管相关技术问题的发生率和类型，然后以双盲方式向导管内注入0.5%布比卡因（1.5mg/kg）或等渗盐水。随后打开患者胸腔，确定导管位置，并检查肺部。11根导管尖端位于胸膜腔内，3根位于胸膜外，7根实际上位于肺组织内。8例患者肺表面有破口。3例患者发生气胸，其中2例为张力性气胸。胸膜腔内放置导管的患者血浆布比卡因水平在约20分钟时达到最大浓度，但导管实际穿透肺组织时直到60分钟才达到。当导管进入肺组织时，血浆布比卡因水平有显著差异，1例患者达到潜在中毒水平。为评估术中镇痛效果，所有患者均给予异氟烷、氧气和肌肉松弛剂的标准麻醉。术前向胸膜内导管注入布比卡因或生理盐水的两组患者之间异氟烷需求量无显著差异。结论是，盲插胸膜内导管可能有危险，尤其是在正压通气后。此外，导管置于肺组织内（这种情况并不少见）会延迟血浆浓度峰值出现的时间，并可能增加中毒风险。在开胸手术期间，胸膜内布比卡因未被发现是全身麻醉的有用辅助药物。
