Laparoscopic colorectal surgery is complex and more technically demanding than many common laparoscopic procedures performed by general surgeons. Advanced laparoscopic skills are required to manipulate and mobilize sections of bowel, control and divide large mesenteric vessels, extract large specimens, and create an anastomosis. The degree of dissection performed can be extensive because of the broad attachments of the colon and rectum. The technical difficulty of these operations raises the likelihood of complications, and the learning curve for laparoscopic colorectal surgery is well documented.
Complications can occur at any point during a laparoscopic operation, from the insertion of the first trocar to its removal and the closing of all incisions. Although knowing how to identify and manage complications is important, anticipation and prevention is prudent. Broadly speaking, complications of laparoscopic colorectal surgery can be categorized into two groups: those relating to laparoscopy in general, and those specific to intestinal operations. General complications include those related to needle/trocar placement and removal, pneumoperitoneum, deep venous thrombosis, and use of electrocautery. Complications specific to colorectal laparoscopy include those related to patient positioning, bleeding, localization of tumors, contamination, anastomosis creation, and urologic injuries.
Although historically laparoscopy has been restricted to certain patients, currently the only absolute contraindication for its use is the inability of the patient to tolerate general anesthesia or a laparotomy. Relative contraindications, such as previous abdominal surgery, pregnancy, morbid obesity, and pulmonary disease, can be limited through careful planning, surgical skill, and experience. Some surgeons believe that the hand-assist laparoscopic technique is helpful.
Peritoneal Access Complications
Obtaining access to the peritoneal cavity can be complicated in several ways. Injuries may occur during initial trocar placement or during placement of secondary trocars. Initial trocar placement is associated with injury to large intra-abdominal vascular structures and bowel perforation, whereas secondary trocar placement is associated with injury to intra-abdominal vessels—as well as those in the abdominal wall—and bowel and bladder perforation. The bladder and stomach should be fully decompressed to reduce the risk of organ perforation during trocar placement.
Although we avoid its use under any circumstances, Veress needle use should at least be limited to patients without previous abdominal surgery, periumbilical inflammation, or hernias. Gripping and elevating the abdominal wall and dissection to identify the fascia during insertion may reduce the risk of injury to underlying structures. Aspiration through the needle should always be performed after placement and prior to insufflation. The presence of blood or enteric content should immediately raise concern for injury and mandates immediate exploration for the site of injury. Initially this exploration may be performed using laparoscopy in a stable patient, but laparotomy is often warranted in the event that the extent of the injury cannot be evaluated or large vessels are involved.
The safest way to obtain initial peritoneal access is through an open technique using a Hassan trocar, which permits direct visualization and identification of underlying structures, although similar complications are still possible. Regardless of technique, after initial trocar placement and insertion of the laparoscope, care should be taken to inspect the surrounding anatomy for injury prior to continuing with the procedure.
Placement of secondary trocars should always be under direct visualization into an area clear of visceral structures. Transilluminating the abdominal wall during secondary trocar placement, as well as positioning ports lateral to the rectus, can reduce injury to the inferior epigastric vessels. Suprapubic trocar placement carries the risk of bladder laceration, especially if the bladder is not fully decompressed, and theoretically can be identified by gaseous filling of the urine collection bag or bloody urine.
Minor complications of trocar placement include an air leak around the port, which may cause difficulty in obtaining or maintaining pneumoperitoneum, and minor skin level bleeding at the insertion site. Tightening the skin around the port with sutures or towel clips can close air leaks, and skin-level bleeding is often self-limiting or easily controlled with electrocautery. Incisional hernias at extraction sites for colorectal surgeries are equivalent to those of any open procedure. Port site hernias are rare as long as the fascia at the site of trocars 10 mm or larger is closed.
Improper Veress needle or trocar placement can cause subcutaneous or preperitoneal emphysema upon insufflation. More rarely, pneumothorax, pneumomediastinum, or pneumopericardium may occur as well. Insufflation should be immediately released with the occurrence of any of these conditions. Subcutaneous emphysema is usually self-limited and resolves within hours postoperatively with minimal intervention. Patients with large amounts of subcutaneous carbon dioxide may experience hypercarbia and acidosis, which should be treated with prolonged mechanical hyperventilation until the excess carbon dioxide can be cleared. Preperitoneal insufflation also is not of great clinical significance but may make proper access to the peritoneal cavity difficult and may require moving trocars to a new site or conversion to laparotomy.
Gas embolism, although rare, is the most feared complication of pneumoperitoneum. This potentially fatal event occurs when a large amount of carbon dioxide is introduced to the venous circulation. The gas collects in the right heart and creates a vapor lock, causing a right outflow obstruction that leads to sudden cardiovascular collapse. High suspicion for this complication should occur with any sudden drop in patient end-tidal carbon dioxide. Treatment includes immediate release of pneumoperitoneum, administration of 100% oxygen, and placement of the patient in Trendelenburg position with the left side down to allow blood to flow under the air bubble. The gas is then aspirated from the heart via a central venous catheter.
Other complications of pneumoperitoneum include arrhythmias/vasovagal events and postoperative shoulder pain. Peritoneal distension causes a reflex vagal response, which may lead to significant arrhythmias or bradycardia. Treatment includes release of pneumoperitoneum and administration of an anticholinergic agent. When the arrhythmia has resolved, pneumoperitoneum may be slowly reintroduced. Recurrence of the arrhythmia may require conversion. Postoperative shoulder pain is caused by diaphragmatic irritation from retained carbon dioxide. Although it is very common, no treatment is required beyond attempting to prevent the occurrence by thoroughly evacuating all gas at the end of the procedure.
Postoperative deep venous thrombosis and pulmonary embolism are relatively uncommon after laparoscopy because of earlier postoperative mobilization. Prolonged reverse Trendelenburg positioning, as well as impaired venous return with intra-abdominal pressures greater than 15 mm Hg, may lead to venous stasis and risk of thromboembolism. Intermittent use of pneumatic compression stockings and pre- and postoperative subcutaneous heparin should be used as prophylaxis in any patient undergoing major laparoscopic surgery unless otherwise contraindicated.
The use of electrocautery in laparoscopy raises the concern for inadvertent thermal injury. Such injuries may occur outside of the field of vision of the operator and can be difficult to identify.
The four major causes of electrosurgical injuries are inadvertent tissue contact, insulation failure, direct coupling, and capacitive coupling. Bipolar, monopolar, and ultrasonic tools generate significant heat, which may cause thermal injury if the active tips make inadvertent contact with a structure. This type of injury occurs when active instruments are not kept in view, as well as when introducing or removing a potentially hot instrument tip. Insulation failure occurs when a break in insulation provides an alternate path for energy, leading to thermal injury to tissue adjacent to the instrument. Injury by direct coupling occurs when an active electrode makes contact with another conductive instrument. In capacitive coupling, the accumulation of electromagnetic current in conductors near the surgical field, such as retractors or clamps, occasionally can generate enough energy to cause injury.
Electrosurgical complications are best prevented through careful and mindful control of instruments. The active tip of thermal devices should always be kept in the field of view, and care should be taken when removing or repositioning these tools to avoid electrosurgical and mechanical injury. All instruments, especially reusable tools, should be routinely inspected for insulation integrity. Surgeons must be aware of warning signs of inadvertent current discharge, including a reduction in anticipated electrosurgical effect, electrostatic interference on the monitor, or involuntary abdominal muscle contraction.
Thermal injury to the bowel is particularly worrisome because burns may progress to full-thickness injury and perforation if they are unrecognized. Small burns recognized at the time of the operation are best treated with suture imbrication, whereas larger burns may require a segmental resection. Missed full-thickness injuries may present with peritonitis within hours or as intra-abdominal sepsis days after perforation occurs.