Adequate barrier pressure (BrP), calculated by subtracting intragastric pressure (IGP) from lower esophageal sphincter pressure (LESP), is believed to prevent gastroesophageal regurgitation (GER). However, the occurrence of intraoperative GER, the height and acidity it reached, have rarely been demonstrated simultaneously along with BrP. In this study, we developed preattached multichannel intraluminal impedance monitoring combined with pH-metry (the gold standard for detecting both height and acidity) on a solid-state manometry to continuously detect intraoperative GER as well as BrP changes. We used this system to record LESP, IGP, and changes in impedance through multichannel sensors and pH in patients receiving elective gynecological laparoscopy with laparoscopic pneumoperitoneum and Trendelenburg (LPT) positioning. Changes in BrP were analyzed at three time points (T1: before LPT; T2: during LPT when LESP reached its peak; and T3: after the offset of LPT). Our results indicated that this preattached experimental setup is feasible for intraoperative applications. GER was not detected in our patients throughout LPT. The mean LESP at T2 (23.22 mmHg) was significantly higher than at T1 (13.23 mmHg), but comparable to that at T3 (18.91 mmHg). The mean IGP (3.24 mmHg) at T2 was significantly higher than at T1 and T3 (- 6.10 and - 2.25 mmHg, respectively). The mean BrP scores were comparable from T1 to T3 (T1: 19.34 mmHg; T2: 19.98 mmHg; T3: 21.16 mmHg). Based on our results, the proposed setup is helpful for intraoperative monitoring and management of patients at high risk of GER.
Trial registration: ClinicalTrials.gov NCT03332901.
Keywords: Barrier pressure; Gastric regurgitation; Manometry; Multichannel intraluminal impedance and pH monitoring.