全身麻醉体外循环下气管导管套囊压力与体温的关系及其临床意义

目的 研究全身麻醉CPB下心内直视手术患者气管导管套囊压力的变化与体温的关系,探讨其临床意义.方法 本研究为前瞻性、随机的临床研究.择期行全身麻醉CPB下心内直视手术的患者40例,按随机数字表法分为2组(每组20例):初始气管导管套囊压力25 cmH2O(1 cmH20=0.098 kPa)组(A组)及初始气管导管套囊压力30 cmH2O组(B组),记录降温和复温过程中两组患者在不同温度点的套囊压力以及术中CPB时间、心脏停搏时间、术后机械通气时间、术后住院天数和呼吸系统并发症情况. 结果 两组患者年龄、性别、BMI、术中CPB时间、心脏停搏时间、术后机械通气时间、术后住院天数和呼吸系统并发症发生率的差异均无统计学意义(P＞0.05).与36℃时的套囊压力比较,各温度点套囊压力的变化差异均有统计学意义(P＜0.05).当降至最低温度28 ℃时,A组套囊压力降低(17.8±9.9)％,B组套囊压力降低(24.2±7.2)％,差异有统计学意义(P＜0.05).与A组比较,B组各温度点的套囊压力均显著高于A组,差异有统计学意义(P＜0.05). 结论 对于行全身麻醉CPB下心内直视手术的患者,CPB低温会造成套囊压力的明显降低.在临床应用中,25 cmH2O及30 cmH2O的套囊压力均较安全.

Relationship between cuff-pressure of endotracheal tube and temperature on patients under cardiopulmonary bypass anesthesia and its clinical significance

Objective Investigating the relationship between the cuff-pressure of endotracheal tube and temperature on patients under CPB anesthesia and explore its clinical significance.Methods This is a prospective clinical study with randomly selected cases.Forty patients undergoing selective surgery under CPB anesthesia with tracheal intubation were randomly divided into 2 groups(n=20):25 cmH2O(1 cmH2O=0.098 kPa) as initial cuff-pressure of endotracheal tube(group A) and 30 cmH2O as initial cuffpressure (group B).The pressure of the tracheal tube cuff was recorded at different temperature points during cooling and warming.Meanwhile,CPB time,circulatory arrest time,postoperative mechanical ventilation time,postoperative hospitalization days and respiratory complications were recorded.Results There was no statistical difference between groups concerning age,sex,BMI,CPB time,circulatory arrest time,postoperative mechanical ventilation time,postoperative hospitalization days and respiratory complications (P＞0.05).The pressure of the tracheal tube cuff during cooling and warming was significantly different with that at initial temperature (P＜0.05).When the temperature dropped to 28 ℃,the decreased percentages were(17.8±9.9)％ and (24.2±7.2)％ respectively(P＜0.05).The pressure was significantly higher in group B than in group A at the same temperature points (P＜0.05).Conclusions For patients under CPB anesthesia,hypothermia will significantly reduce the cuff-pressure of endotracheal tube.In clinical practice,both 25 cmH2O and 30 cmH2O used as the pressure of the tracheal tube cuff are safe.