Different Maneuvers for Reducing Post-laparoscopic Pain

* Laparoscopic surgeries are becoming more attractive because of early recovery. However, post-laparoscopic shoulder and upper abdominal pain may cause more discomfort to the patient than the pain at the incision site
* Many strategies have been attempted, such as the use of nonsteroidal anti-inflammatory drugs; however, the effect is limited, and there are no reliable methods available yet.
* Recently, some techniques are introduced that can potentially alleviate various types of pain through different mechanisms in patients after laparoscopic surgery such as low-pressure pneumoperitoneum, intraperitoneal normal saline infusion, and pulmonary recruitment maneuvers.
* the investigators conduct this randomized controlled trial to evaluate the effectiveness of different strategies on reducing the intensity of post-laparoscopic shoulder and abdominal pain in patients undergoing laparoscopic gynecologic surgeries.

Laparoscopic surgery is becoming more popular due to smaller incision, faster recovery, less postoperative pain, and earlier returns to normal activity . However post-laparoscopic shoulder and upper abdominal pain may upset the patient more than the pain at the incision site. The incidence of shoulder pain after laparoscopic gynecological surgery varies from 35% to 80% and could be so severe at 24 hours after laparoscopic hysterectomy as well.

The mechanism of post laparoscopic shoulder and abdominal pain attributes to the insufflated co2 in the abdominal cavity and become entrapped between the liver and the right diaphragm causing irritation of the phrenic nerve, diaphragm and referred pain in the C4 dermatome. On the other hand, the prolonged exposure to residual CO2 dissolution leads to intra-abdominal acidosis and consequent peritoneal irritation and abdominal pain.

As long as the retention of CO2 is the key factor in the laparoscopy-induced shoulder and abdominal pain, many strategies have been evolved to alleviate different types of pain in patients undergoing laparoscopic surgeries such as usage of low-pressure pneumoperitoneum (8-10 mmHg) that result in reducing the intensity of postoperative pain in comparison to standard high-pressure pneumoperitoneum (12-15 mmHg). Although this low pressure may impair visualization and jeopardize the surgeon's comfort during surgery, this method is proven to be safe and feasible.

One of the maneuvers that have been proposed is an intraperitoneal normal saline infusion (IPS) that increases intraperitoneal pressure to enhance the removal of residual CO2, as well as offers a physiologic buffer system to wash out excess CO2.

Pulmonary recruitment maneuvers (PRM) has also a potential beneficial effect on alleviating post-laparoscopic pain by mechanically increasing intraperitoneal pressure to accelerate the elimination of residual CO2.

Because these variable techniques are mediated through different mechanisms, the investigators hypothesize that combination of two different maneuvers may be ideal and more effective in reducing post-laparoscopic shoulder and abdominal pain than any single or standard maneuver in patients undergoing laparoscopic gynecologic surgeries.

Eligibility Criteria:
Inclusion Criteria:

* Patient acceptance.
* BMI ≤35 kg/m2.
* ASA I and ASA II.
* Scheduled for elective laparoscopic gynecologic surgeries for benign lesions under general anesthesia.

Exclusion Criteria:

* Patients with pre-existing chronic pain disorders.
* Patients on opioid or sedative use.
* Psychological and mental disorders.
* Severe hypertensive, cardiac, hepatic and renal patients.