Following laparoscopic surgery, residual carbon dioxide (CO2) trapped between the liver and the diaphragm induces phrenic nerve irritation and causes more patient discomfort than pain at the incision site. Although the pulmonary recruitment maneuver can mechanically remove residual CO2 and reduce pain, its effects occur only immediately after the operation and disappear later. Intraperitoneal normal saline infusion, another procedure, washes out CO2 with a physiologic buffer system and maintains longer pain relief. These 2 interventions are mediated through different mechanisms and act in different phases.
This randomized controlled trial (RCT) tested the hypothesis that combining the pulmonary recruitment maneuver and intraperitoneal normal saline infusion would reduce postlaparoscopic shoulder and upper abdominal pain. Subjects were randomly assigned to the combined intervention or a control group receiving only passive deflation at the end of the procedure. Data for 100 patients were included in the analysis, 50 in the intervention group and 50 in the control group. The primary study end point was patient-reported postlaparoscopic upper abdominal pain and shoulder pain measured using a visual analog scale. Ratings for pain were obtained 12, 24, and 48 hours after surgery.
The incidence of laparoscopic-induced shoulder pain at 12, 24, and 48 hours was lower in the intervention group (54%, 46%, and 30%, respectively) compared with the control group (72%, 70%, and 50%, respectively; P = 0.008, P = 0.001, and P = 0.004, respectively). To reduce the incidence of shoulder pain, the number needed to treat was 6 (95% confidence interval [CI], 4–21) at 12 hours, 5 (95% CI, 3–10) at 24 hours, and 5 (95% CI, 4–15) at 48 hours. At 12, 24, and 48 hours after surgery, the incidence of laparoscopic-induced upper abdominal pain also was lower in the intervention group (78%, 72%, and 58%, respectively) than that in the control group (92%, 90%, and 70%, respectively; P = 0.006, P = 0.001, and P = 0.077, respectively).
These data show that the combined pulmonary recruitment maneuver and intraperitoneal normal saline infusion significantly reduce postlaparoscopic shoulder and upper abdominal pain. This intervention is inexpensive and easy to implement in daily clinical practice.