Postlaparoscopic reduction of pain by combining intraperitoneal normal saline and the pulmonary recruitment maneuver

Shoulder pain and pain in the upper abdomen are common complaints after
laparoscopy. The incidence of shoulder pain ranges from 35 to 80%. Sometimes
this laparoscopy-related pain is even worse than the pain at the incision site.
Laparoscopy*induced pain is thought to be caused by retention of carbon dioxide
in the abdomen, which irritates the phrenic nerve and diaphragm and causes
referred pain in the shoulder and pain in the upper abdomen.

A promising strategy to reduce postlaparoscopic shoulder pain and abdominal
pain is the pulmonary recruitment maneuver. By using manual pulmonary
inflations, the intraperitoneal pressure increases and removal of residual
carbon dioxide will be facilitated. Another method is the use of
intraperitoneal normal saline infusion. As carbon dioxide is lighter than
normal saline, it rises and escapes the abdomen more easily. Besides, normal
saline is thought to offer as a physiologic buffer system to dissolve excess
carbon dioxide. In this randomized study, reduction of postlaparoscopic pain
will be estimated by using a combination of the two therapies mentioned.

Randomized controlled trial, in two teaching hospitals in the Netherlands.

In the intervention group, the upper abdomen will be evenly and bilaterally
filled with warmed isotonic normal saline (15-20 ml/kg body weight) and left in
the abdominal cavity. Then the patient is placed in Trendelenburg position (30
degrees), and the anesthesiologist will perform five manual pulmonary
insufflations with a pressure of maximum 40 cm H2O (pulmonary recruitment
maneuver). The fifth positive pressure inflation will be held for 5 seconds.
The trocar sleeve valves will be left open, so the carbon dioxide can escape
the abdominal cavity. Then de patient is placed in neutral position and the
instruments are removed from the abdomen.
In the control group, the carbon dioxide is removed from the abdominal cavity
at the end of the surgery, with gentle abdominal pressure and passive
exsufflation through the port sites, with the sleeve valves open.

Previous studies show that intraperitoneal normal saline infusion is a safe
procedure. Likewise, the pulmonary recruitment maneuver is a proven safe
procedure when inflating with a maximum pressure of 40 cm H2O. Literature shows
there are no related complications with these two interventions. Participants
fill out short questionnaires at three different moments, 8, 24 and 48 hours
after surgery. 24 Hours postoperative, patients are phoned to ask for (serious)
adverse events. The expected benefit is a decrease in incidence and severity of
pain in shoulder and upper abdomen after laparoscopic surgery.