全凭静脉麻醉时双相气道正压面罩通气下胃食管反流的监测

目的 监测全凭静脉麻醉(TIVA)下双相气道正压(BiPAP)面罩通气时的胃食管反流情况,评估该通气方法 在伞身麻醉中应用的安全性.方法 选择择期行腹腔镜胆囊切除手术的成年患者40例,美国麻醉师协会(ASA)分级Ⅰ～Ⅱ级,无胃食管反流危险因素,随机分为面罩通气组(Ⅰ组)和气管内插管通气组(Ⅱ组),每组20例.麻醉前经鼻置人胃食管舣探头pH电极,使远端探头位于食管下段(A点),近端探头置于食管中上段(B点).麻醉诱导后,两组分别应用BiPAP面罩通气和间歇正压机械通气(IPPV),连续实时监测同术期食管下段及中上段pH值变化直至患者清醒.以pH值小于4.0作为胃食管反流的诊断标准.结果 麻醉后30 min、气腹后30 min、麻醉结束后pH值监测结果 显示,Ⅰ组食管下段pH 值分别为5.43±0.51、5.24±0.47、5.36±0.53;Ⅱ组食管下段pH值分别为5.37±0.67、5.29±0.68、5.36±0.78.Ⅰ组和Ⅰ组食管下段及食管中上段各时点pH值监测无1例小于4.0,反流发生率均为0,两组比较pH值差异无统汁学意义(P>0.05).结论 在无胃食管反流病史的患者行腹腔镜胆囊切除术时,应用BiPAP而罩通气全身麻醉不增加胃食管反流概率,是较安全的方法 之一.

Monitoring the gastroesophageal reflux during hi-level positive airway pressure mask ventilation under total intravenous anesthesia

Objective To evaluate the safety by monitoring the gastroesophageal reflux during bi-level positive airway pressure (BiPAP) mask ventilation under total intravenous anesthesia (TIVA). Methods Forty adult patients, scheduled for elective laparoscopic cholecystectomy, ASA Ⅰ to Ⅱ, were randomly divided into group Ⅰ (ventilated by mask, n = 20) and Ⅱ (ventilated by endotrcheal tube, n = 20). Risk factors of gastroesophageal reflux were excluded in all the patients. Before anesthesia, gastroesophageal bi-probe pH electrode was inserted through nostril, and ensure that the distal probe was located in the lower part of esophagus (site A), and the proximal probe in the middle or upper part (site B). After anesthesia induction, the patients of two groups received BiPAP mask ventilation or endotracheal intermittent positive pressure ventilation(IPPV), respectively. The pH value of the lower and middle or upper part of esophagus was monitored continuously and real-timely till the patients awake. Diagnosis of gastroesophageal reflux was confirmed when pH < 4.0. Results At 30 min after anesthesia, 30 min after artificial pneumoperitoneum and instantly after the end of anesthesia, the pH values of lower part of esophagus were 5.43 ± 0. 51,5.24 ± 0.47 and 5.36 ±0.53 in group Ⅰ ,and 5.37 ±0.67, 5.29±0.68 and 5.36±0. 78 in group Ⅱ , respectively. In two groups, no pH value of the lower and middle or upper part of esophagus under 4.0 was observed at all time points, and no reflux manifested in all the patients. There was no significant difference of pH value and incidence of reflux between two groups (P > 0. 05). Conclusion BiPAP mask ventilation does not increase the incidence of gastroesophgeal reflux in patient without history of gastroesophageal reflux undergoing laparoscopic cholecystectomy during general anesthesia, therefore, it should be a safe ventilation technique.