Effects of general anesthesia maintenance without muscle relaxants for double-balloon enteroscopy: a randomized controlled trial

Objective To evaluate the feasibility and safety of maintaining general anesthesia without neuromuscular blockade in oral double-balloon enteroscopy. Methods Totally 120 patients undergoing oral double-balloon enteroscopy under general anesthesia were randomly assigned into two groups: the observation group and the control group. The observation group was not given muscle relaxants for anesthesia maintenance, while the control group was given muscle relaxants punctually. Observation indexes were monitored, including the mean arterial pressure (MAP), heart rate (HR), peak airway pressure (Ppeak) and end-tidal CO2 partial pressure (PETCO2) before anesthesia (T0), immediately after intubation (T1), at the time of endoscopy placement (T2), at the end of endoscopy withdrawal (T3), and at the time of waking-up (T4). The cases of spontaneous breathing recovery before the end of endoscopy, postoperative recovery time, extubation time, length of PACU stay, postoperative adverse reactions and satisfactory rates were recorded. Results Twelve cases were removed by the exclusion criteria, and the remaining 108 cases completed the study, including 56 cases in the observation group and 52 cases in the control group. The one-time success rate of induction was both 100% in the two groups. There were no significant differences in MAP, HR, Ppeak, and PETCO2 between the two groups at each observation point (all P>0.05), and the same is true for within group comparison with T0 (all P>0.05). The recovery rate of spontaneous respiration in the observation group was significantly higher than that in the control group [100% (56/56) VS 42% (22/52), χ2=44.73, P=0.000]. The awaken time, extubation time and length of PACU stay were 6±2 min, 10±3 min, and 11±4 min, respectively, in the observation group, compared with 15±5 min (t=-12.64, P=0.000), 17±5 min (t=-8.90, P=0.000), and 17±7 min (t=-5.73, P=0.000) in the control group. None of the patients required assisted ventilation. Hypoxemia occurred in 2 cases and nausea in 3 cases in the control group, while only nausea occurred in 1 patient in the observation group. The overall incidence of adverse reactions was not statisticaly different between the two groups (P>0.05). Anesthesia satisfaction rate of two groups was 100%. Conclusion It is feasible and safe to perform oral double-balloon enteroscopy without muscle relaxants during maintaining under general anesthesia, with quick recovery of spontaneous breathing and awakening, early extubation and less cost. Key words: Anesthesia, intravenous; Without muscle relaxants; Double-balloon enteroscopy