Complications of Laparoscopic and Robotic-Assisted Surgery

The benefit of any surgical intervention is weighed against the risk of complications. Although experience is of obvious importance, not even the most veteran surgeon is immune to complications that may occur during or after an operation. Many of the complications that may occur during laparoscopic or robotic-assisted retroperitoneal surgery are similar to those encountered with traditional open surgery. However, controlling these events requires a unique skill set. Moreover, some complications are unique to laparoscopy. Complications from laparoscopic or robotic-assisted procedures may arise from almost every aspect of the operation, and when complications do occur, early recognition and aggressive treatment are crucial to minimize subsequent morbidity to the patient. In this chapter, we review the potential complications that can occur in each of these areas. Strategies aimed at complication prevention, recognition, and treatment are discussed.

Positioning Injury

Attention to patient positioning is of great import during laparoscopy in order to avoid postoperative orthopedic and neuromuscular injuries. Complications include sensory and motor deficits, neuralgias, back pain, and rhabdomyolysis. Such injuries are more common after retroperitoneal versus pelvic laparoscopic surgery, with an occurrence of 3.1% reported in the literature. Careful attention to patient positioning is imperative to avoid compression or stretch injuries to the extremities, particularly the brachial plexus. Prevention includes using foam pads at pressure points, maintaining the head in the neutral position, and, when indicated, adding a properly placed axillary or chest roll. When the patient is in dorsal lithotomy position or split leg position, care must be exercised in maintaining a straight line from the patient’s heel to knee to contralateral shoulder. Hip overextension must be prevented as well.

Rhabdomyolysis is a potentially serious complication of laparoscopic and robotic-assisted surgery. The incidence of clinical rhabdomyolysis after laparoscopic surgery in the flank position has been reported to be as high as 0.4% and is associated with several factors, including male gender, heavier weight, large muscle mass, longer operative times, and the use of a full flank or exaggerated lithotomy position. Management includes intravenous hydration with or without alkalization.

Skin breakdown and pressure sores are also a potential complication secondary to patient positioning and are associated with the flank position and prolonged operative times.

Insufflation Injury

Incorrect placement of a Veress needle can result in inadvertent insufflation of extraperitoneal spaces with subsequent extravasation of gas along tissue planes. The most common site of incorrect needle placement is the preperitoneal space ( Fig. 12-1 ), resulting in an increased distance between the skin and peritoneal cavity, which may necessitate open trocar placement to gain access. Moreover, preperitoneal or retroperitoneal insufflant can pass between diaphragmatic fibers or alongside the great vessels, causing pneumomediastinum, which, in turn, can lead to pneumopericardium or pneumothorax.

Insufflation of the subcutaneous space can be a result of incorrect Veress needle placement or secondary to leakage of gas around trocars. The resultant subcutaneous emphysema is usually of no clinical consequence; once the procedure is complete, the gas is absorbed. However, extensive dissection of gas can lead to pneumothorax, pneumomediastinum, and hypercarbia. The risk of development of a pneumomediastinum increases when crepitus is noted extending up to the neck. Because of a continuum of fascial planes existing between the cervical soft tissue and mediastinum, the potential exists for gas to track upward into the neck and down into the mediastinum ( Fig. 12-2 ). Subclinical thoracic air collections have been reported in 5.5% of urologic laparoscopic procedures, which can often be managed conservatively because of the high solubility of CO ₂. However, if symptomatic pneumothorax or pneumomediastinum develops, the pneumoperitoneum should be discontinued and the ectopic gas evacuated.

A pneumothorax can also occur in the absence of subcutaneous emphysema. Insufflant can enter the pleural space through anatomic or congenital defects in the diaphragm. Complications of anesthesia and positive pressure ventilation, as well as patient conditions such as emphysematous bullae, can also lead to the entry of air into the pleural cavity.

After the pneumoperitoneum is successfully established, the presence of pressurized gas in the abdominal cavity has significant and variegated physiologic consequences that can result in complications. The cumulative response of the cardiovascular system during laparoscopy with CO ₂under moderate pressure (10 to 20 mm Hg) is usually sufficient for healthy individuals to tolerate pneumoperitoneum. However, patients with significant cardiovascular or pulmonary disease may not compensate sufficiently. In addition, careful attention to insufflation pressure is critical to avoid excessive tension and potential cardiovascular collapse.

Although appropriate ventilatory adjustments are usually sufficient to eliminate the increased CO ₂load that results from laparoscopy, in some patients CO ₂insufflation can produce profound hypercapnia. This can be exacerbated by subcutaneous emphysema and excessive intra-abdominal pressures. If severe, hypercapnia and acidosis can have significant depressive cardiac effects. Initial management consists of lowering the intra-abdominal pressure. If the anesthesiologist cannot adequately compensate, helium may be used or the procedure may need to be converted to open surgery.

Insufflation can also produce significant cardiac arrhythmias, including bradycardia, tachycardia, ventricular extrasystoles, atrioventricular dissociation, and nodal rhythms. Hypercapnia, as well as a vagal response to abdominal distention and peritoneal irritation, has been implicated. The use of atropine before insufflation may prevent these vagal reactions.

A rare but potentially fatal complication related to the pneumoperitoneum is a gas embolism, which occurs most commonly during the induction of pneumoperitoneum. Although intravasation of gas as a result of the increased intra-abdominal pressure has been suggested as a cause, the most common cause is direct placement of a needle or trocar into a vessel or abdominal organ. In a meta-analysis of nearly 500,000 laparoscopic procedures with closed access, the incidence of gas emboli was 0.0014%.

Patient survival after gas embolism depends on rapid diagnosis and treatment. The diagnosis can be difficult, and there is often no warning before acute cardiovascular collapse, particularly during insufflation. When the size of the embolus increases, tachycardia, arrhythmias, hypotension, and increased central venous pressure may be noted. Hypoxia, hypercapnia, and cyanosis may also be evident. Electrocardiographic changes can include a right heart strain pattern, and auscultation may reveal the classic “mill wheel” murmur just before the acute event. Also, an acute decrease in measured end-tidal CO ₂measurements is noted as the embolism occludes the pulmonary trunk ( Fig. 12-3 ). When an embolism is suspected, release the pneumoperitoneum and administer 100% oxygen. Place the patient in the left lateral decubitus position with the head down to move the gas away from the pulmonary artery ( Fig. 12-4 ). Institute cardiopulmonary resuscitation, and place a central venous catheter in an attempt to aspirate the gas. Percutaneous or open evacuation of the gas may be indicated.

Cautery Injury

A thermal injury to tissue represents a serious complication because patients do not show symptoms of such injuries for several days postoperatively. Failure to recognize such an injury can result in significant morbidity. Prevention of burns depends on the careful use of electrocautery. Before using electrocautery, inspect all instruments, including robotic manipulators, to be certain that insulation is intact. Insulation defects can result in arcing of the electrocautery current between instruments. Moreover, when current is applied, the entire tip of the instrument must be kept within the visual field. Finally, be certain that the tissue to be cauterized is isolated from surrounding tissue to prevent inadvertent injury secondary to thermal conduction through tissue.

Vascular Injury

Vascular injuries are among the most common and challenging complications of urologic laparoscopy, occurring in 2.8% of procedures. Vascular injury can be a result of Veress needle and trocar placement or from trauma sustained during dissection. Many of these injuries are minor and are easily managed, whereas others have catastrophic potential. A thorough understanding of vascular anatomy and constant attention to maintaining orientation are critical to avoid vascular complications, and early recognition of such an event is key to minimizing the extent of injury.

Slight bleeding from the trocar or Veress needle access often resolves without intervention, though several maneuvers are available to control bleeding from abdominal wall vessels. If the bleeding is minor, apply electrocautery under direct vision. If the bleeding is brisk, pass a Foley catheter down the trocar, then inflate the balloon and put on traction to tamponade the bleeding vessel ( Fig. 12-5 ). More significant bleeding may require sutures to achieve hemostasis. Pass a figure-of-eight suture using a Carter-Thomason needlepoint fascial closure device (Inlet Medical, Eden Prairie, Minn.) ( Fig. 12-6 ). If this maneuver is unsuccessful, open exploration may be indicated.

Occasionally, abdominal wall or intra-abdominal vessel injury is not noted until the postoperative period. Hypotension or tachycardia associated with a decreasing hematocrit raises the suspicion of ongoing hemorrhage. Significant pain about a trocar site, ecchymosis, and a palpable paramedian mass are signs of a hematoma within the rectus sheath. Correction of any underlying coagulopathy is the initial step; continued hemodynamic instability, however, would warrant exploration for persistent bleeding.

Trocar placement can also result in major vessel injury and is related to the use of excessive force to advance the trocar. This is a particular risk with extremely thin patients; the great vessels can be deceptively close to the abdominal wall. Major bleeding may not be immediately recognized if the injury is confined to the retroperitoneum. When a major trocar injury is suspected, perform immediate laparotomy. Leave the trocar in place to help tamponade the vessel and aid in localizing the site of injury. Do not move the trocar, to prevent converting a puncture into a larger tear. Attempt to control bleeding proximally and distally. Moreover, it is important to mobilize the vessel and inspect the back wall for a possible through-and-through injury.

A mesenteric hematoma may occur as a consequence of trocar placement or dissection. If identified, closely monitor the hematoma. Evidence of expansion or compromise to bowel circulation warrants exploration.

Vascular injury can also occur during dissection. Each injury is individual and requires unique definitive treatment; however, general recommendations can be made. Most vascular injuries related to the upper urinary tract involve branches of the renal vein or vena cava, although arterial injuries are possible. Take care to avoid placing undue tension on veins during dissection of venous branches. It is important to realize that an instrument passed through a trocar site acts as a lever. Accordingly, significant torque can be generated at the tip of a given instrument ( Fig. 12-7 ), whether laparoscopic or robotic. The lack of haptic feedback found on the robotic console can make it difficult to appreciate the torque being applied to the tissue. Be cautious, therefore, when positioning retractors on viscera or the mesentery. Follow basic tenets of open surgery, such as the avoidance of past-pointing the tip of the scissors when cutting.