充气式止血带对下肢手术患者围术期肺换气功能的影响

Effect of Pneumatic Tourniquet on the Perioperative Pulmonary Ventilation Function in Patients Undergoing Lower Limb Surgery

目的探讨充气式止血带对下肢手术患者围术期肺换气功能的影响。方法选择美国麻醉医师协会(ASA)Ⅰ～Ⅱ级择期行单侧下肢手术上止血带时间超过60min的患者11例(止血带组)和不上止血带下肢手术患者10例(对照组)。分别于上止血带前或术前(T0)、松开后或手术结束后1/2h(T1)、2h(T2)、6h(T3)、24h(T4),取桡动脉血行血气分析,计算肺泡动脉氧分压差(PaA-aDO2)、呼吸指数(RI)。结果止血带组T3时刻氧分压(PaO2)较对照组明显降低,差异有统计学意义(P<0.05)。止血带组各时刻二氧化碳分压(PaCO2)与对照组比较,差异均无统计学意义(P>0.05)。止血带组T3PaA-aDO2较对照组明显升高,差异有统计学意义(P<0.05)。止血带组T3、T4RI较对照组明显升高,差异有统计学意义(P<0.05)。结论使用止血带时间超过60min的下肢手术患者,在止血带松开后1d内可发生肺换气功能损害,产生低氧血症,加强围手术期护理或常规给予吸氧极为重要。

Objective To investigate the effect of pneumatic tourniquet deflation on pulmonary gas exchange in patients undergoing lower limb surgery.Methods Twenty-one patients with American Society of Anesthesiologists physical status I or II,who underwent unilateral lower extremity surgery,were divided into control group using no tourniquet （n=10） and trial group （n=11） receiving the continuous tourniquet inflation for more than 60 min.Radial arterial blood samples for blood gas analysis were collected immediately before tourniquet inflation or operation （T0）,and 1/2 h （T1）,2 h （T2）,6 h （T3）,24 h （T4） after tourniquet deflation or operation ending.Alveolo-arterial oxygen partial pressure difference PaA-aDO2and respiratory index （RI） were calculated.Results At T3 the value of arterial oxygenation （PaO2） in the trial group was decreased significantly as compared with the control group （P0.05）,but no significant difference was found in arterial partial pressure of carbon dioxide （PaCO2） between the two groups （P0.05）.At T3 the value of PaA-aDO2 in the trial groups was increased significantly as compared with the control group （P0.05）;and at T3 and T4 the values of RI in the trial groups were increased significantly as compared with the control group （P0.05）.Conclusion The patients undergoing lower limb surgery may have impaired pulmonary gas exchange with hypoxemia within one day following removing the continuous tourniquet inflation for more than 60 min.It is very important to enhancing perioperative nursing or conventional oxygen therapy.