COPD: Typically, the abdomen is insufflated using carbon dioxide (CO₂). Those with chronic obstructive pulmonary disease (COPD) are at danger of developing hypercarbia secondary to CO₂ reabsorption after insufflation, but may benefit postoperatively from reduced narcotic requirements and improved pulmonary toilet. In patients with normal pulmonary function, this CO₂ is easily removed from the body by the lungs. However, the lungs ability to do so in COPD is impaired, resulting in hypercarbia. Methods to decrease the CO₂ reabsorption in those with COPD include changing the insufflation gas to helium and lowering intraabdominal insufflation pressure to 10-12 mm Hg.

Pregnancy: This was previously believed to be a relative contraindication to laparoscopic surgery but now is not. Concerns were raised in regard to placental ischemia induced by pneumoperitoneum. These concerns were not corroborated in animal studies. In animal models, intraabdominal pressure (IAP) up to 10 mm Hg was considered safe; however, increasing the working pressure to 20 mm Hg produced maternal and fetal cardiopulmonary compromise. In fact, laparoscopic cholecystectomy and appendectomy are considered the standard of care during pregnancy.

Obesity: Obesity was previously believed to be a relative contraindication to laparoscopic urologic surgery, but is no longer. In fact, the postoperative morbidity decrease from laparoscopic surgery is greater in the obese population as compared with the normal population. It has been shown, in upper urinary tract laparoscopic surgery, that patients with BMI greater than 30 kg/m² had higher operative time, blood loss, and transfusion rates as compared with lean counterparts. However, major and minor complications were no different in the obese population. Conversion rates and analgesic requirements were also no different in lean versus obese patients.

Previous abdominal surgery: Intraabdominal adhesions were previously thought to be a contraindication to laparoscopic surgery but are no longer. There are circumstances in which a laparoscopic lysis of adhesions (LOA) should not be undertaken, including peritonitis, hemodynamic instability, and coagulopathy. However, in the overwhelming majority of patients, laparoscopic LOA can be done with efficiency and safety, provided the surgeon is familiar with the technique. In fact, laparoscopic LOA has been shown to confer a quicker recovery of bowel function and fewer wound complications as compared with open LOA. Minimally invasive retroperitoneal approaches can also be utilized to avoid the potential adhesions seen after previous intraabdominal surgery.

The Veress needle has a spring-loaded inner sheath. When the needle engages tissue, this sheath retracts, allowing the needle to puncture the tissue. Once the needle passes into the peritoneal cavity, the sheath deploys and guards the needle tip which greatly decreases the likelihood of injury to intraabdominal vessels and viscera.

Safe access to the peritoneal space via the Veress technique is accomplished by employing the technique correctly. Three “clicks” are heard when the needle passes through the following layers on the anterior abdominal wall: skin, anterior rectus sheath, and posterior rectus sheath. Once the third “click” is heard, the needle should be held in this position. Rotating the needle could cause intraabdominal injuries if the needle is in the wrong position. The needle should then be aspirated, and the contents of aspiration should be examined. Succus or blood indicates the needle is in bowel or vasculature, respectively. If this is the case, the needle should not be removed. Instead, an alternate Veress needle puncture site should be chosen and the above technique repeated. After the initial aspiration, 2 cc of saline should be irrigated, and aspiration should be repeated. The needle should aspirate easily. The saline should quickly drop into the peritoneal space, provided the needle is in the correct location.

The needle can then be connected to high-flow insufflation. The caliber of the Veress needle limits the inflow to no greater than 3 L/min. Attention should be paid to the pressure transduced, which should be less than 10 mm Hg. There are a number of reasons why the initial insufflation pressure may initially read greater than 10 mm Hg. If the needle is abutting an intraabdominal viscus, pressure may be elevated. In this circumstance, pressure may be reduced by retracting the abdominal pannus up, away from this viscus. In very obese patients, the weight of the abdominal wall may cause increased initial pressures, which will decrease with continued insufflation. If the abdomen is not uniformly insufflated, and the pressure persists greater than 10 mm Hg, the needle is in the preperitoneal space and needs to be advanced.

The primary trocar can then be advanced via a blind or optical trocar (nonbladed). The laparoscope is then introduced to survey the abdomen for anatomic variation, adhesions, and damage to viscera or vessels from the Veress needle or initial trocar. Remaining trocars can then be placed under direct visualization. The Veress needle is removed, and the insufflation tubing is connected to the camera trocar.

The first step in this technique is accessing the peritoneal space via a 12-mm or smaller incision. A Hasson or balloon trocar can be used. The trocar can be affixed to the fascia to ensure that it is not dislodged during the procedure. Insufflation is then connected to this trocar, and the abdomen can be surveyed. The sutures used to affix the trocar to the fascia can be used at the conclusion of the procedure to close the fascial defect.

The Hasson technique should be used in children and pregnant patients. It should also be noted that current literature does not support the closed or the open technique as safer relative to the other.

The overall effect of pneumoperitoneum produces no change in cardiac output. Pneumoperitoneum compresses the vasculature, increasing peripheral arterial resistance and central venous pressure. Increased central venous pressure leads to decreased peripheral venous return. The heart rate increases in response to decreased preload, and cardiac output remains the same. However, arrhythmias are more common with pneumoperitoneum. CO₂ induces hypercarbia and acidosis and increases the sympathetic response, all of which contribute to an increased incidence of arrhythmias.

Pneumoperitoneum increases IAP. This increase in IAP is transmitted to the thoracic cavity. The result of the increased thoracic cavity pressure is decreased compliance, thereby increasing peak and mean airway pressures. Also, vital capacity is reduced. CO₂ diffuses into the thoracic cavity, causing hypercarbia and acidosis. Hypercarbia induced by CO₂ is usually inconsequential in those with normal pulmonary function. However, as mentioned previously, those with COPD may have difficulty eliminating this excess CO₂. As such, arterial blood gases may be used to measure arterial CO₂ saturations in this patient population. If hypercarbia develops, decreasing the IAP to 10 mm Hg and/or changing the insufflation gas to helium can reduce this effect.

Many robot-assisted pelvic surgeries are done with the patient positioned in steep Trendelenburg. Trendelenburg positioning reduces chest wall compliance, impairing O₂