全麻下妇科腹腔镜手术患者胃食管反流的发生 喉罩和气管导管通气下的比较

Incidence of gastro-esophageal and-hypopharyngeal reflux during gynecological laparoscopy: laryngeal mask vs tracheal tube

目的比较全麻下妇科腹腔镜手术患者应用喉罩和气管导管对下咽部及食道中上段反流的影响。方法在全身麻醉控制通气下,择期行妇科腹腔镜手术患者60例,ASA Ⅰ或Ⅱ级,无胃、食道反流危险因素,随机分为气管导管(TT)组和喉罩(LMA)组,每组30例。麻醉诱导后,放置喉罩和气管导管,机械控制通气。经口明视下置入胃食道双探头pH电极,其中近端探头置于下咽部食道上段扩约肌开口处,远端探头位于食道中上段。连续、同步监测围术期下咽部及食道中上段pH值变化直至患者清醒。pH值降至4．0及以下,即提示胃管反流发生。结果 LMA组与TT组下咽部及食道中上段反流发生率差异无统计学意义(P>0．05)。结论在严格选择反流低危病例的前提下,与TT 相比,LMA用于全麻下控制呼吸妇科腹腔镜手术并不增加下咽部及食道中上段的反流机率。

Objective To compare the incidence of gastro-esophageal and -hypopharyngeal reflux during gynecological laparoscopy performed under general anesthesia and mechanical ventilation with tracheal intubation （TT） and laryngeal mask airway （LMA）,Methods Sixty ASA Ⅰ or Ⅱ patients aged 18-60 yrs with BMI 〈 30 kg · m^-2 undergoing elective gynecological laparoscopy were randomly divided into 2 groups （n = 30 each）： LMA group and TT group. Patients with hiatus hernia or having a history of gastro-esophageal regurgitation or those who had received H2-antagonist within 2 weeks or operation on upper alimentary tract were excluded from the study. Anesthesia was induced with fentanyl 2-3 μg·kg^-1 , propofol 2-3 mg·kg^-1 and vecuronium 0.08-0.1 mg·kg^-1 . laMA was inserted or tracheal intubation was performed after induction. The patients were mechanically ventilated （VT = 8-10 ml·kg^-1, RR = 12 bpm, I：E = 1：2, FiO2 = 100% ）. PETCO, was maintained at 35-45 mm Hg. In laMA group the peak airway pressure was kept≤21 cm H2O. Anesthesia was maintained with isoflurane 1.0%- 1.5 % and propofol infusion （2-3 mg·kg^-1·h-1 ） and intermittent Ⅳ boluses of fentanyl and vecuronium. The two electrodes of a pH-sensitive probe were placed in hypopharynx and esophagus between middle and upper third respectively. Local pH was continuously monitored, pH ≤ 4 was taken as a sign of reflux. Results The two groups were comparable with regard to age, body weight, BMI and duration of anesthesia, operation and pneumoperitoneum. The incidence of gastro-hypopharyngeal regurgitation was low in both groups （0 in LMA group and 3.3% in TT group）. The incidence of gastro-esophageal reflux was 40% in LMA group and 26.7% in TT group. The difference was not statistically significant between the two groups （ P 〉 0.05）. Conclusion In low risk patients the incidence of gastro-esophageal regurgitation is comparable in patients undergoing gynecological laparoscopy in head-down position under general anesthesia and mechanical ventilation using either LMA or TT.