The most basic laparoscopic procedure is diagnostic laparoscopy. A laparoscope is usually placed at the umbilicus to visualize the abdominal cavity. Depending on the objectives of the procedure, the scope alone can be used to visualize the surface of the
small intestines, omentum, some of the colon and stomach, liver, spleen, uterus, some of the diaphragm, and the peritoneal surface. Intra-abdominal adhesions, evidence of malignancy or carcinomatosis, ascites, ischemic bowel, hernias, cirrhosis, foreign bodies, or bleeding can all be discovered by placement of the laparoscope alone. With placement of one additional 5-mm port site, a grasper can be used to move the omentum or take down adhesions. A transabdominal core biopsy needle can be used to biopsy the liver or other lesions, and a suction device can be used to collect ascites for specimen analysis. With the placement of a second 5-mm port site, the surgeon has two instruments to fully manipulate structures and perform a formal diagnostic laparoscopy, which can include running the entire small bowel and visualizing the lesser sac. With the use of bed positioning and gravity retraction, the deep pelvis and significant portions of the left and right diaphragms as well as the spleen can be visualized. The small bowel can be run with atraumatic bowel graspers that range in length from 1.8 to 2.5 cm, with either corrugated, wavy, or serrated surfaces. Starting either at the terminal ileum or at the ligament of Treitz is acceptable. Frank disease of the colon can be recognized from the cecum to the rectum, although a detailed examination would require medial mobilization off of the retroperitoneum.

It was clear prior to the advent of laparoscopic cholecystectomy that the use of a laparoscope to explore the peritoneal cavity for obvious diagnoses such as carcinomatosis, and equivocal presentations of pelvic and abdominal pain, was also a clear advantage over laparoscopy compared with laparotomy. The caveat was, and still is, that its value is to make diagnoses such as carcinomatosis or penetrating injury to viscous structures but at the risk of missing diagnoses. The decision to perform diagnostic laparoscopy depends on the surgeon, and its relative benefit has to be measured. On the other hand, staging laparoscopy for malignancies such as gastric or pancreatic neoplasm to exclude unresectable disease is now the standard of care.

The clearest clinical indications for laparoscopic general surgery beyond simple diagnosis include cholecystectomy, weight loss procedures such as the Roux-en-Y gastric bypass, sleeve gastrectomy, and adjustable gastric band, Nissen fundoplication, Hellar myotomy, and staging laparoscopy. On the aggressive end of the spectrum of indications is the concept that any patient who would otherwise require laparotomy and is hemodynamically stable can undergo attempted laparoscopy. These may include patients with bowel obstruction, penetrating and blunt trauma, complex hernias, malignancies, perforated gastric or duodenal ulcers, volvulus, perforated diverticulitis, and so forth. Available evidence, surgeon comfort level, patient preference, hospital resources, and sometimes common sense will dictate the decision to move ahead with laparoscopy.

The evidence supporting the flagship procedure for laparoscopy—the cholecystectomy—is not supported by randomized controlled trials compared with open cholecystectomy, but by an abundance of data purporting its decreased pain, hospital stay, and return to work, with its associated cost savings and equivalent safety profile. Laparoscopic cholecystectomy was the first procedure to prompt a systematic review of its safety and efficacy by the National Institutes of Health (NIH) when widespread mishap regarding common bile duct injury was suspected. Comparative studies have since recognized its value in management of acute cholecystitis.

In the past 20 years, the number of abdominal procedures with supporting evidence in favor of a laparoscopic approach has increased to the majority. The NIH has since published consensus statements for laparoscopic bariatric surgery and colon surgery. The strength of compelling evidence is strongest with the former and weakest for the latter. Other operations supported by compelling data for a standard laparoscopic approach include foregut surgery, and solid organ removal such as adrenalectomy, nephrectomy, distal pancreatectomy, and splenectomy. Laparoscopy for hernia repair was best delineated for inguinal hernias initially in cases of recurrence and bilaterality. Although surgeon comfort level and more recent evidence supporting a laparoscopic approach for de novo unilateral hernia exists, the original indications remain steadfast. Ventral and incisional hernias remain a varied entity according to size, location, and extent of intra-abdominal adhesions. Meta-analyses looking at laparoscopic versus open repairs suggest consistently that the largest advantages are in reduction of wound-related complications such as infection, hematoma, and separation. Seroma formation is equally common with laparoscopic repair, but pain, recurrence, hospital stay, and other economic and outcome parameters appear equivalent. Case reports and small series exist for more complex procedures such as pancreaticoduodenectomy (Whipple procedure), liver resection, and total gastrectomy, but have yet to demonstrate themselves as standard procedures.

The contraindications to laparoscopy have not changed—hemodynamic instability and inability of the patient to tolerate a laparotomy. The inherent issues of increased operative time and the physiologic effect of peritoneal insufflation on cardiac output make placing a scope in an unstable patient irresponsible. All other contraindications are relative. Chronic obstructive pulmonary disease, prior surgeries, generalized peritonitis, and bowel obstruction require adequate surgeon comfort and discussion with the patient regarding the relative merits and risks (Table 1).

When a patient is deemed a candidate for a laparoscopic operation, the specific history relevant to this approach includes the acuity and complexity of their disease process, a history of chronic obstructive pulmonary disease, cardiac risk factors, and prior abdominal surgeries. Pulmonary function
testing and assessment of baseline hypoxia and hypercarbia may be necessary, and the results may indicate laparoscopy to be more precarious than laparotomy in borderline cases. Cardiac risk factors are relevant to the patient’s anesthetic risk as well as to the suspected insult of the planned procedure, but the reduction of cardiac output caused by pneumoperitoneum may need to be factored in. No amount of prior abdominal surgery contraindicates laparoscopy, but the location of scars and any history of adhesions encountered on prior surgeries are considered. Patient-specific variations in adhesion formation, inflammatory and infectious processes, foreign bodies such as mesh, and immunosuppression may all impact the degree of intra-abdominal scar formation. For example, remote colectomy required for perforated diverticulitis and frank peritonitis may indicate a more hostile abdomen than a patient who underwent an equivalent colectomy for benign disease.