Less is more: clinical impact of decreasing pneumoperitoneum pressures during robotic surgery

Review of Outcomes of Low Verses Standard Pressure Pneumoperitoneum in Laparoscopic Surgery

BACKGROUND

Carbon dioxide pneumoperitoneum during laparoscopy changes cardiorespiratory physiology and contributes to post-op pain. We studied outcomes before and after implementing low-pressure pneumoperitoneum QI project.

METHODS

Forty-two patients were insufflated at standard pressures (15 mmHg) while 41 were insufflated using low (8-12 mmHg) during laparoscopic procedures. These variables were obtained from the patient chart: pain scores, intravenous morphine milligram equivalents (MME), peak inspiratory pressures (PIP), end-tidal CO₂ (EtCO₂), surgery duration, and patient demographics. The study was conducted after IRB approval.

RESULTS

Low-pressure pneumoperitoneum is feasible and the surgeon can increase to 10-12 mmHg as needed. The mean post-op IV MME was significantly decreased in the low-pressure group (11.75 ± 10.41) compared to the standard pressure group (17.36 ± 18.1) (t-test, P = .047). Mean peak inspiratory pressures during insufflation were significantly higher for procedures conducted at standard pressure (31.40 ± 4.82) compared to the 8 mmHg (24.68 ± 4.19) and 12 mmHg (27.33± 3.85) low pressure groups (one-way ANOVA, P < .0001). During insufflation, there was a significant increase in the average EtCO₂ in the standard pressure group (42.07 ± 5.60) compared to the 8 mmHg low pressure group (37.59 ± 5.05) (ANOVA, P = .0096). Constant flow insufflation was more likely to be performed at low pressure than demand mode (58% v. 33%).

CONCLUSION

Low pressure pneumoperitoneum decreases PIP pressure and CO2 absorption evidenced by lower ETCO2 intra-operatively. Patients have significant improvement in postoperative pain evidenced by decreased narcotics needed. Low pressure pneumoperitoneum using a constant flow insufflator is safe and results in improved patient outcomes.

The "Dark Side" of Pneumoperitoneum and Laparoscopy

Laparoscopic surgery has been one of the most common procedures for abdominal surgery at pediatric age during the last few decades as it has several advantages compared to laparotomy, such as shorter hospital stays, less pain, and better cosmetic results. However, it is associated with both local and systemic modifications. Recent evidence demonstrated that carbon dioxide pneumoperitoneum might be modulated in terms of pressure, duration, temperature, and humidity to mitigate and modulate these changes. The aim of this study is to review the current knowledge about animal and human models investigating pneumoperitoneum-related biological and histological impairment. In particular, pneumoperitoneum is associated with local and systemic inflammation, acidosis, oxidative stress, mesothelium lining abnormalities, and adhesion development. Animal studies reported that an increase in pressure and time and a decrease in humidity and temperature might enhance the rate of comorbidities. However, to date, few studies were conducted on humans; therefore, this research field should be further investigated to confirm in experimental models and humans how to improve laparoscopic procedures in the spirit of minimally invasive surgeries.