An Individualized Low-Pneumoperitoneum-Pressure Strategy May Prevent a Reduction in Liver Perfusion during Colorectal Laparoscopic Surgery

High intra-abdominal pressure (IAP) during laparoscopic surgery is associated with reduced splanchnic blood flow. It is uncertain whether a low IAP prevents this reduction. We assessed the effect of an individualized low-pneumoperitoneum-pressure strategy on liver perfusion. This was a single-center substudy of the multicenter ‘Individualized Pneumoperitoneum Pressure in Colorectal Laparoscopic Surgery versus Standard Therapy II study’ (IPPCollapse–II), a randomized clinical trial in which patients received an individualized low-pneumoperitoneum strategy (IPP) or a standard pneumoperitoneum strategy (SPP). Liver perfusion was indirectly assessed by the indocyanine green plasma disappearance rate (ICG–PDR) and the secondary endpoint was ICG retention rate after 15 min (R15) using pulse spectrophotometry. Multivariable beta regression was used to assess the association between group assignment and ICG–PDR and ICG–R15. All 29 patients from the participating center were included. Median IAP was 8 (25th–75th percentile: 8–10) versus 12 (12,12) mmHg, in IPP and SPP patients, respectively (p < 0.001). ICG–PDR was higher (OR 1.42, 95%-CI 1.10–1.82; p = 0.006) and PDR–R15 was lower in IPP patients compared with SPP patients (OR 0.46, 95%-CI 0.29–0.73; p = 0.001). During laparoscopic colorectal surgery, an individualized low pneumoperitoneum may prevent a reduction in liver perfusion.

A multifaceted individualized pneumoperitoneum strategy for laparoscopic colorectal surgery: a multicenter observational feasibility study

BACKGROUND

While guidelines for laparoscopic abdominal surgery advise using the lowest possible intra-abdominal pressure, commonly a standard pressure is used. We evaluated the feasibility of a predefined multifaceted individualized pneumoperitoneum strategy aiming at the lowest possible intra-abdominal pressure during laparoscopic colorectal surgery.

METHODS

Multicenter prospective study in patients scheduled for laparoscopic colorectal surgery. The strategy consisted of ventilation with low tidal volume, a modified lithotomy position, deep neuromuscular blockade, pre-stretching of the abdominal wall, and individualized intra-abdominal pressure titration; the effect was blindly evaluated by the surgeon. The primary endpoint was the proportion of surgical procedures completed at each individualized intra-abdominal pressure level. Secondary endpoints were the respiratory system driving pressure, and the estimated volume of insufflated CO₂ gas needed to perform the surgical procedure.

RESULTS

Ninety-two patients were enrolled in the study. Fourteen cases were converted to open surgery for reasons not related to the strategy. The intervention was feasible in all patients and well-accepted by all surgeons. In 61 out of 78 patients (78%), surgery was performed and completed at the lowest possible IAP, 8 mmHg. In 17 patients, IAP was raised up to 12 mmHg. The relationship between IAP and driving pressure was almost linear. The mean estimated intra-abdominal CO₂ volume at which surgery was performed was 3.2 L.

CONCLUSION

A multifaceted individualized pneumoperitoneum strategy during laparoscopic colorectal surgery was feasible and resulted in an adequate working space in most patients at lower intra-abdominal pressure and lower respiratory driving pressure. ClinicalTrials.gov (Trial Identifier: NCT03000465).