Complications of laparoscopic surgery

INTRODUCTION — The rate of serious complications associated specifically with a laparoscopic approach is low overall. Severe complications such as vascular injury and bowel perforation are the main cause of morbidities and mortality related to laparoscopic surgery. Conversion to an open procedure may be needed to manage complications that have been identified intraoperatively, while others may not be recognized until the postoperative period.

Surgical complications unique to a laparoscopic approach are discussed here. Surgical techniques and their specific complications are discussed in individual topic reviews. Other general issues relating to laparoscopic surgery, including abdominal access and instrumentation, are reviewed elsewhere. (See "Abdominal access techniques used in laparoscopic surgery" and "Instruments and devices used in laparoscopic surgery" and "Overview of gynecologic laparoscopic surgery and non-umbilical entry sites" and "Overview of laparoscopy in children and adolescents".)

EPIDEMIOLOGY AND RISK FACTORS

Prevalence — The rate of complications associated specifically with a laparoscopic approach is low overall. As an example, 0.2 to 18 percent of gynecologic laparoscopies are associated with any complication; 0.6 to 14.6 percent are associated with a major complication; and 0.02 (0.01 to 0.03) percent result in a fatality [1]. Access-related vascular and gastrointestinal injuries are the leading causes of fatalities following laparoscopic surgery [2].

Up to one-half of complications occur at the time of abdominal access for camera or port placement [3,4]. Additional complications arise from abdominal insufflation, tissue dissection, and hemostasis [5]. Neurologic injury can also occur, and can be mitigated by careful patient positioning [6].

Risk factors — The rate of complications may go up with one or more of these risk factors:

●Prior surgery – Patients who have had prior surgery for intra-abdominal or pelvic disease (eg, diverticulitis, pelvic inflammatory disease) have a higher risk of complications related to adhesions.

●Complexity of surgery – Conditions such as extensive bowel distention, very large abdominal or pelvic mass, and diaphragmatic hernia may increase the complication rate.

●Patient comorbidities – Patients with poor cardiopulmonary reserve may not be candidates for abdominal insufflation given the physiologic changes related to pneumoperitoneum.

●Surgeon learning curve – The frequency of complications may be related to surgeon experience and the number of specific procedures performed for some, but not all, types of surgical procedures [7,8]. Studies focusing on various laparoscopic surgeries have had mixed conclusions [9-14].

VASCULAR INJURIES — The overall reported rate of vascular injury (arterial or venous injury) ranges from 0.1 to 6.4 per 1000 laparoscopies [15]. Vascular injury is second only to anesthesia as a cause of death from laparoscopy [16-18]. In one review, the mortality rate among patients suffering a vascular injury was as high as 15 percent [19].

Entry-related vascular injuries — In laparoscopy, 50 to 83 percent of all vascular injuries occur during abdominal access [1]. Although a Veress needle is often implicated as the cause of distal aortic or iliac vessel injury, vascular injuries can occur with any of the available devices using open or closed techniques during any laparoscopic procedure, including those in the upper abdomen (eg, laparoscopic cholecystectomy) [2].

Major vessels — The incidences of initial entry-related major vascular injury ranges from 0.4 to 4 in 1000 [4,20-22]. Amongst large retroperitoneal vessels, the right iliac arteries are injured in 41 to 48 percent of cases, followed by the right iliac veins (38 percent), left iliac veins (29 percent), aorta (13 to 25 percent), inferior vena cava (6 to 11 percent), and mesenteric vessels (6 to 17 percent) [15,23].

Major vascular injuries may occur due to a lack of appreciation for the proximity of important vascular structures to the anterior abdominal wall [24]. The distance from the anterior abdominal wall to the aorta can be as little as 2 cm in thin individuals. The distal aorta, which lies directly beneath the umbilicus, and right common iliac artery, which crosses the midline, are each particularly prone to injury [25]. Techniques for minimizing vascular injuries are discussed in detail elsewhere. (See "Abdominal access techniques used in laparoscopic surgery", section on 'Choice of technique'.)

Major vascular injuries may be recognized immediately by observing free blood in the abdominal cavity. However, vascular injury may not be appreciated right away due to bleeding into the mesentery or retroperitoneum rather than into the peritoneal cavity.

The anesthesia team should be immediately notified that there is a problem. For patients in lithotomy position (eg, gynecologic, rectal surgery), it is advisable to maintain the extremities in an elevated position to minimize hypotension. For upper abdominal procedures for which the patient has been placed into reverse Trendelenburg position, the bed should be flattened or placed into Trendelenburg position, as needed.

Managing injury to a major vessel requires subspecialty expertise, and consultation with a surgeon experienced with vascular procedures should be obtained without delay. If a vascular or trauma surgeon is not immediately available (community facility, ambulatory surgery center), we advocate a damage control approach as used in trauma surgery [23,26]. To minimize ongoing blood loss, the abdomen should be rapidly opened with a midline incision, pressure should be applied directly to the bleeding site for initial control, and the abdominal cavity can be packed, if needed. These maneuvers allow for fluid resuscitation while awaiting the vascular or trauma surgeon or arrangements for immediate transfer if subspecialty expertise is not available. Techniques for packing the abdomen in the setting of acute hemorrhage are discussed elsewhere. (See "Surgical management of splenic injury in the adult trauma patient", section on 'Packing' and "Overview of damage control surgery and resuscitation in patients sustaining severe injury", section on 'Damage control laparotomy'.)

Injury to the aorta, vena cava, or iliac vessels during abdominal access can lead to rapid exsanguination and death unless prompt vascular control and repair are undertaken. Major vascular injuries are associated with a 6 to 31 percent mortality rate [23,26] and are responsible for 74 to 82 percent of all laparoscopy-related deaths [2,27,28].

Minor vessels — Most laparoscopic entry-related vascular injuries involve minor vessels including those of the abdominal wall, omentum, mesentery, or other organs. As an example, during initial abdominal access to establish pneumoperitoneum, the omental and mesenteric vessels in the path of the initial entry may be injured, particularly if there are adhesions [16,29].

Minor superficial bleeding sites can usually be identified using probing instruments or an irrigator-aspirator. Once identified, the site can be coagulated or clipped. Although the injured vessel is considered minor, these injuries are often a cause for transfusion, conversion to an open procedure, or reoperation.

Inferior epigastric vessels — The perforation of abdominal wall vessels (inferior and superficial epigastric arteries and muscular perforating vessels) by secondary trocars is reported in 0.3 to 2.5 percent of laparoscopic procedures [30]. Of these, injury to the inferior epigastric vessels compromises 48 percent all laparoscopic vascular injuries [15].

Abdominal wall vessels can be injured if the trocar is not placed under direct vision. Visualization by transillumination is typically for the superficial vessels; transillumination of the deep vessels (eg, inferior epigastric) is almost impossible. Instead, the deep vessels should be directly visualized or assumed to be medial to the insertion of the round ligament/spermatic cord into the deep inguinal ring. Cutting trocars with sharp blades are more likely to injure vessels compared with smooth, conical-tip trocars that push superficial vessels out of the way (9 versus 3 percent) [31].

If an inferior epigastric bleed is identified intraoperatively, it can be stopped in many different ways, including direct pressure using the trocar, electrocautery, or open or laparoscopic transfixing suture [24]. A partially lacerated inferior epigastric artery may not spontaneously stop bleeding because the vessel is tethered and cannot retract and spasm. Bleeding due to a vascular injury at a port site may not be observed with the port site cannulas in place and the abdomen insufflated due to tamponade. Thus, it is important to remove each trocar under direct laparoscopic vision to ensure no bleeding.

Delayed bleeding can occur after the patient has left the operating room, which typically present as abdominal wall hematomas two or three days after surgery [32]. Clinical manifestations include abdominal wall pain, abdominal wall or flank ecchymosis, and external bleeding from a trocar site. Patients can also present initially with hemodynamic instability due to significant blood loss from a port site that bleeds internally.

Patients with an abdominal wall hematoma from laparoscopic access who are hemodynamically stable and with no signs of hematoma expansion can be managed conservatively (image 1). The hematoma may drain spontaneously through one or more port sites. Intervention is indicated if the hematoma expands, the patient becomes hemodynamically unstable, or the hematoma becomes infected. For some patients, percutaneous embolization of the bleeding vessel may be an option [33]; however, rapidly expanding hematomas leading to hemodynamic instability or infected hematomas are more effectively managed using an open surgical approach.

Dissection-related vascular injuries — Although vascular injuries are more commonly related to abdominal access, vascular injury related to the dissection phase of laparoscopic surgery can occur from inadvertent electrocautery away from the field of dissection; excessive thermal spread; improper staple length, height, or stapling technique; or failure to recognize a significant vascular structure prior to its division with nonvascular stapling instrument. Ten to 20 percent of major vascular injuries are caused by electrosurgical devices, followed by dissecting instruments or stapling devices [15,23].

Prevention of bleeding by meticulous hemostasis during dissection is a fundamental principle of laparoscopic surgery. The identification of significant hemorrhage should prompt the surgeon to immediately notify the anesthesiologist for fluid resuscitation, transfusion, or potential need to convert to an open procedure.

Mild-to-moderate bleeding can often be controlled with compressive maneuvers. Local compression allows a surgeon time to consider strategies for definitive hemostasis and may be a definitive treatment. Most small to medium-sized vessels will spasm, and bleeding slows and often stops altogether with simple compression. To provide local compression, a gauze sponge can be passed through a 10 mm port to compress the identified area of bleeding. Soaking the sponge with dilute (1:10,000 or 1:100,000) epinephrine has also been described for controlling bleeding during laparoscopic cholecystectomy [34] and laparoscopic Heller myotomy [35]. Under some circumstances, a piece of healthy and mobile omentum can be grasped and used to compress the area. This technique is useful for sudden, significant bleeding from division of the short gastric arteries during laparoscopic fundoplication or laparoscopic splenectomy.

Dry hemostatic agents (eg, Surgicel, Gelfoam) can easily be passed through a laparoscopic port and used in conjunction with mechanical compression. Fibrin glue (with the aid of a special laparoscopic applicator) has also been used to provide hemostasis during laparoscopic surgery [36]. Topical hemostatic agents are discussed in detail elsewhere (table 1). (See "Overview of topical hemostatic agents and tissue adhesives".)

Once bleeding has slowed or ceased, the area is inspected to identify the bleeding point, which is isolated and controlled with a clip, suture, electrocautery, or any of the other methods described above. The field should then be irrigated carefully with saline. Irrigation should be used judiciously to minimize soiling of the tip of the laparoscope with blood and other fluids. After controlling bleeding laparoscopically, the surgeon should deflate the pneumoperitoneum, wait a few minutes, and then re-insufflate to confirm that the bleeding is not just tamponaded by pressure.

Conversion to an open procedure — The decision to convert for bleeding is justifiable and prudent. An important source of patient morbidity results from the failure to convert to an open procedure in a timely fashion when bleeding is encountered. Laparoscopic hemostasis that is partially effective or ineffective can lead to significant blood loss and its associated clinical consequences.

The need to convert to an open procedure due to bleeding is determined by the rate of bleeding, the amount of blood loss, the clinical status of the patient (tachycardia, hypotension, sepsis), the presence (or lack) of a clearly defined source, and the comfort of the surgeon with their ability to see and control the bleeding quickly using laparoscopic techniques. Patient factors such as advanced age or poor functional status and comorbidities (cardiopulmonary conditions, obesity, cirrhosis, clotting disorders) should be considered when determining whether laparoscopic attempts at hemostasis are likely to be successful and deciding how long to persist.

When moderate-to-heavy bleeding occurs, vision can be obscured when blood on the inside of the port repeatedly contacts the tip of the cleaned scope each time it is reinserted. A long, cotton-tipped applicator can be used for cleaning the inside of a 5 mm port, but removal or replacement of the port may be needed. If adequate visibility cannot be maintained, conversion to an open procedure will be needed.

It is important to be vigilant about the possibility of injury to local anatomic structures when attempting to control bleeding. As an example, during laparoscopic cholecystectomy, efforts to control a bleeding artery without adequate visibility can lead to application of a clip to the common bile duct or right hepatic artery. Extensive monopolar electrocautery in this region can also result in a thermal injury to the bile ducts or duodenum. (See "Complications of laparoscopic cholecystectomy", section on 'Bleeding complications'.)

BOWEL INJURIES — Bowel injury is the third leading cause of death, after anesthesia and major vascular injury, following a laparoscopic procedure [16-18]. Injury to the gastrointestinal tract occurs in 0.03 to 0.65 percent of patients undergoing laparoscopic surgery [3,4,37]. Forty-one to 50 percent of inadvertent bowel injuries occur during abdominal access [1,3].

Entry-related bowel injuries — The small bowel is the most commonly injured gastrointestinal structure during abdominal access for laparoscopic surgery, but stomach, liver, and colon injuries have been reported when subcostal access techniques are used [38,39]. Decompressing the stomach with an orogastric or nasogastric tube prior to upper abdominal access may minimize the potential for inadvertent stomach injury.

Gastrointestinal injury should be managed when recognized. Iatrogenic small and large bowel injuries are managed as with other traumatic intestinal injuries, based upon the grade of injury (table 2). Most access-related bowel injuries require simple primary closure, reapproximating the bowel wall with simple sutures in one or two layers. For discrete large bowel injuries, colostomy is rarely needed. If the operating surgeon is inexperienced or uncomfortable performing such a repair, we advise consultation with a surgeon experienced with bowel surgery. (See "Traumatic gastrointestinal injury in the adult patient", section on 'Repair by injury grade'.)

Dissection-related bowel injuries — After the initial access, injury to the bowel can result from electrosurgical injury or trauma during dissection or manipulation in 45 percent (range 23 to 57 percent) of the cases that involve a bowel injury [40].

About a quarter to a third of the bowel injuries are caused by an electrosurgical device [1]. Electrosurgical injuries identified in the operating room should be inverted and oversewn to healthy tissue at the margins or resected with a 1 to 2 cm margin around the injury site. It is important to remember that the visible thermal injury is always less than the actual injury. The lateral thermal spread reaches 2 to 22 mm for monopolar instruments, 2 to 6 mm for conventional bipolar instruments, 1 to 6 mm for advanced bipolar instruments, and 1 to 4 mm for ultrasonic instruments [1].

Resection is a reasonable approach if the electrosurgical injury is a significant size and there is any risk of not getting a healthy tissue margin. (See "Traumatic gastrointestinal injury in the adult patient", section on 'Repair by injury grade'.)

Missed bowel injuries — About 30 to 50 percent of bowel injuries go unrecognized [3,37], and, consequently, the patient can present postoperatively with or without peritonitis, often following discharge [41]. In a review of 21 studies of bowel injuries sustained during laparoscopic urologic surgery, nearly one-half of the injuries were not recognized at the time of the surgery [37]. No patient with bowel injury that was recognized intraoperatively sustained a postoperative adverse event, whereas patients with unrecognized injury and presenting in a delayed fashion required multiple procedures to manage the injury. A delayed diagnosis increases the risk of bowel necrosis, perforation, and potentially death [41].

Symptoms related to a missed gastrointestinal injury generally manifest within 12 to 36 hours postoperatively, but the presentation can be delayed for up to five or seven days. If a patient does not gradually improve following laparoscopic surgery and continues to have abdominal pain, especially if associated with tachycardia or fever, bowel injury should be suspected, and evaluation undertaken.

Although demonstration of free intra-abdominal air on imaging studies is a sign of gastrointestinal injury, this sign may not be helpful after laparoscopic surgery because free intra-abdominal air often may be seen on a radiograph up to one week postoperatively, but the volume should gradually decrease with time [42,43]. Increasing amounts of intra-abdominal air suggests ruptured viscus until proven otherwise.

A missed gastrointestinal injury is a surgical emergency and generally should return to the operating room as soon as it is recognized. Once identified, the management of injured bowel depends on the extent of local tissue damage, the amount of peritoneal contamination, and the hemodynamic stability of the patient. This is discussed in another topic. (See "Overview of gastrointestinal tract perforation".)

The overall mortality rate associated with laparoscopic bowel injury is 0.8 percent (0.36 to 3.6 percent), most resulting from delayed diagnosis, which increases the mortality rate to 3.2 to 3.6 percent [39,40].

URINARY TRACT INJURIES — Urinary tract injuries occur most commonly during laparoscopic gynecologic, urologic, and colorectal surgeries. As an example, a urinary tract injury has been reported in 0.5 (0.03 to 1.7) percent of laparoscopic gynecologic surgeries [44-46].

Entry-related bladder injuries — Thirty-six percent of all urinary tract injuries occur during the initial access; the rest occur during subsequent dissections [1]. A history of prior pelvic surgery, including cesarian section, increases the risk of bladder injury [47].

In general, puncture of the bladder results when a midline, suprapubic trocar is placed in a patient with an overdistended bladder. When anticipating port placement below the level of the umbilicus, a Foley catheter should be placed to decompress the bladder. Although it is commonplace for patients to void immediately before the procedure, it is safer to drain the bladder with a catheter after the induction of anesthesia.

The catheter can also provide a means for early recognition of this complication. Clinical signs of bladder injury include gaseous distention of the urinary drainage bag and bloody urine [29,48]. If a bladder injury is suspected, instillation of methylene blue or indocyanine green into the bladder may aid in identifying an injury [49]. If a colored agent is not available, sterile milk or infant formula can also help with injury identification [50]. Management of bladder injury depends on the defect size [49]:

●If the bladder is punctured with a needle (eg, Veress) <2 mm, repair or drainage is generally not needed.

●Small direct trocar injuries <10 mm in the dome of the bladder generally resolve spontaneously with bladder decompression for 7 to 10 days.

●Larger or irregular defects will require a suture closure with absorbable sutures in two layers using an open or laparoscopic approach. The Foley catheter should be left in place for up to two weeks, depending on the size and location of the puncture or tear. Cystogram may be performed prior to catheter removal for complex injuries.

If the operating surgeon is unsure of bladder management, urology consultation should be obtained. (See "Traumatic and iatrogenic bladder injury", section on 'Surgical repair'.)

Dissection-related urinary tract injuries — An electrosurgical device is responsible for 45 and 33 to 48 percent of bladder and ureteral injuries, respectively [1,49]. (See 'Entry-related bladder injuries' above.)

●Bladder injury – This type of injury is most likely to occur during pelvic procedures, such as gynecological and urologic procedures, although it can also happen during inguinal hernia repair [51], diagnostic laparoscopy, or appendectomy. The management of bladder injuries can range from simple catheterization to laparotomy, depending upon the severity of the injury as detailed above. (See 'Entry-related bladder injuries' above.)

●Ureteral injury – Ureteral injury occurs in fewer than 2 percent of pelvic procedures and can result from pelvic dissection during the course of distal colon/rectal, gynecologic, or urologic surgery, or as a result of thermal injury by excessive use of an energy source adjacent to the ureter [52].

If pelvic dissection is anticipated to be in an inflamed operative field or reoperative field, ureteral stents can be used to help identify the ureters to minimize ureteral injury [53,54]; however, injury can still occur with a prophylactic stent in place. The best means of preventing inadvertent ureteral injury are identification of the ureter during the procedure using anatomic landmarks and observation of peristalsis [29]. With complex surgeries or where anatomy is unclear, dissection and mobilization of the ureter (ureterolysis) may be needed [55]. At the conclusion of any laparoscopic procedure in which the operative field is in the vicinity of the ureter(s), the surgeon should confirm and document the integrity of the ureters before closing. (See "Placement and management of indwelling ureteral stents", section on 'Prophylactic' and "Urinary tract injury in gynecologic surgery: Epidemiology and prevention".)

A majority (45 to 85 percent) of bladder injuries but only a minority (3 to 12 percent) of ureteral injuries are diagnosed during surgery [44,46]. In one meta-analysis of the gynecologic literature, routine cystoscopy increases the intraoperative but not postoperative detection rate of urinary tract injury [45]. The evaluation and management of urinary tract injury is discussed in detail elsewhere. (See "Urinary tract injury in gynecologic surgery: Identification and management" and "Surgical repair of an iatrogenic ureteral injury".)

SURGICAL SITE COMPLICATIONS — Laparoscopic surgery utilizes multiple small incisions for trocar placement and specimen extraction. Complications that can occur at such incisions include wound infection, hernia, nerve injury, and tumor implantation (in malignant cases).

Surgical site infection — Wound infection is less common following laparoscopic compared with open procedures; nonetheless, it can produce significant morbidity [56]. The presence of significant peri-incisional erythema, wound drainage, and fever may indicate the development of a necrotizing fascial infection [57-59]. The diagnosis and management of necrotizing fasciitis is discussed in detail elsewhere. (See "Necrotizing soft tissue infections".)

Although the umbilicus is more commonly associated with surgical site infection than other trocar sites, this finding correlates with the use of the umbilicus as a specimen extraction site [60]. The incidence of wound infections can be minimized by appropriate administration of prophylactic antibiotics, sterile technique, and use of bags during specimen extraction. Once established, surgical site infection is treated with drainage, packing, and appropriate antibiotics. (See "Antimicrobial prophylaxis for prevention of surgical site infection in adults" and "Complications of abdominal surgical incisions".)

Trocar site hernia — According to a 2012 systematic review, trocar/port site hernia following laparoscopic surgery occurs with a median prevalence of 0.5 percent (range 0 to 5.2 percent) [61]. One study evaluating the risk for late-onset hernia following a variety of open and laparoscopic surgeries reported incidences of incisional hernia at 1.9 and 3.2 percent at two and five years after laparoscopic surgery, respectively [62]. By comparison, the incidence of incisional hernia for open surgery was 8 and 12 percent, respectively. In a systematic review of incisional hernias following standard multiport laparoscopic cholecystectomy, the incidence of hernias at one year was 0.2 percent, as opposed to 1.5 percent after open cholecystectomy and 4.5 percent after single-incision laparoscopic cholecystectomy [63].

Trocar/port diameter and patient factors can affect the rate of hernia formation:

●Port site hernia appears to be related to more complex procedures that require multiple ancillary ports and larger-diameter ports used for specimen removal, stapling devices, and single-site surgery [64].

●Multiple studies comparing single-site and multiport laparoscopy found an increased risk for hernia in patients who underwent single-site surgery, which requires a larger port [63,65-67].

●The use of port devices designed to minimize leakage of insufflated air (eg, fascial screws) also increases the incision size and may damage fascial tissue, increasing the risk for port site hernia.

●Other factors include older age and higher body mass index. Increased operative times and excess tissue manipulation may also lead to fascial weakening.

Measures one can take to prevent or minimize the chance of trocar hernias are discussed in another topic. (See "Abdominal access techniques used in laparoscopic surgery", section on 'Fascial closure'.)

Clinical manifestations of port site dehiscence/hernia include gross disruption of the wound with drainage, presence of a bulge with exertion or Valsalva, or painful continuous bulge if bowel or omentum is incarcerated. The patient can also present with clinical signs of bowel obstruction or infarction. When physical findings are equivocal, imaging studies may help secure the diagnosis [68]. (See "Etiologies, clinical manifestations, and diagnosis of mechanical small bowel obstruction in adults".)

When port site hernia is identified following laparoscopy, the site should be repaired to prevent the development of intestinal complications (ie, obstruction, strangulation). The management of incisional hernias is discussed in detail elsewhere. (See "Management of ventral hernias".)

Extraction site hernia — In complex laparoscopic gastrointestinal or gynecologic surgery, one or more surgical specimens may require an extended incision for specimen extraction. Incisional hernias could develop at the specimen extraction site, the risk of which is correlated with their size and location.

In a single-center retrospective study of 2148 patients undergoing laparoscopic colorectal resection, a variety of extraction sites were used at the surgeon's discretion, including infraumbilical midline (24 percent), stoma site in the left or right lower quadrant (15 percent), periumbilical midline (23 percent), Pfannenstiel (30 percent), and midline converted (9 percent) [69]. At a follow-up of 5.9±3 years, the overall extraction site incisional hernia rate was 7.2 percent. Extraction site hernias were most common at periumbilical midline (13 percent) and midline converted (12 percent) locations and least common at the Pfannenstiel location (0.9 percent). Besides location of the extraction site, other risk factors include obesity (hazard ratio [HR] 1.23), concurrent port site hernia (HR 3.66), and postoperative surgical site infection (HR 2.11). Thus, whenever feasible, an extraction site that is off the midline, such as Pfannenstiel, should be selected to minimize the risk of extraction site hernia.

Trocar site metastasis — Trocar/port site metastasis refers to cancer growth at a port incision site after laparoscopic tumor resection [70]. Port site metastasis occurs after 0.4 to 2.3 percent of laparoscopic procedures performed in the presence of intraperitoneal malignancy [71].

Purported mechanisms include hematogenous spread or direct contamination by tumor cells, secondary effects from pneumoperitoneum (eg, immune suppression), and surgical technique [71]. Although it is not clear whether port site metastases can be prevented, suggested measures to minimize the risk of port site metastases include the use of wound protectors and specimen extraction bags, and irrigation of the port sites with povidone-iodine to prevent tumor growth [72]. Once diagnosed, port site metastasis is treated surgically with port site excision [73].

Peripheral nerve injuries — Nerve injuries can occur during laparoscopic surgery due to patient position; the Trendelenburg position is responsible for most upper extremity nerve injuries, and the lithotomy position is responsible for most lower extremity nerve injuries (common peroneal, sciatic, or femoral nerve) [74].

The incidence of positioning related injuries can be as high as 6.6 percent and is magnified in robotic cases or procedures with prolonged operative time. The highest risk is for peripheral nerve injury in patients requiring extended periods in abnormal positions [6]. Careful patient positioning and padding of pressure points is essential to minimizing nerve stretch and pressure in laparoscopic and robotic surgery, minimizing time in lithotomy position may also reduce this risk [75].

In addition to positioning-related nerve injuries, the ilioinguinal and iliohypogastric nerves can be injured during lateral trocar insertion or fascial closure of the lateral ports [76]. The hypogastric, sciatic, obturator, and the posterior hypogastric plexus may be injured during pelvic dissection [77].

RELATED TO PNEUMOPERITONEUM — Complications related to insufflation of gas needed to create pneumoperitoneum include subcutaneous emphysema, mediastinal emphysema, pneumothorax, cardiac arrhythmia, carbon dioxide retention (hypercarbia), postoperative pain related to retained intra-abdominal gas, and air embolism due to venous injury. (See 'Vascular injuries' above.)

Subcutaneous emphysema — Subcutaneous emphysema is due to insufflation of an improperly positioned pneumoperitoneum needle (eg, Veress) or port [78]. Methods to prevent this complication during initial abdominal access are discussed elsewhere. (See "Abdominal access techniques used in laparoscopic surgery", section on 'Initial port placement'.)

Physiologic effect of pneumoperitoneum — Other complications (eg, mediastinal emphysema [79], pneumothorax [80], cardiac arrhythmia such as bradycardia [81], carbon dioxide retention) are related to the physiologic side effects of insufflation [82]. Patients who have poor cardiopulmonary reserve are not likely to be offered a laparoscopic procedure, and thus these complications are uncommon. Physiologic effects and related complications of pneumoperitoneum are reviewed in detail separately. (See "Anesthesia for laparoscopic and abdominal robotic surgery in adults", section on 'Physiologic effects of laparoscopy' and "Anesthesia for laparoscopic and abdominal robotic surgery in adults", section on 'Intraoperative complications'.)

Some degree of postoperative shoulder pain can be expected in 50 to 80 percent of patients after laparoscopic surgery and is related to irritation of the phrenic nerve and stretching of the parietal peritoneum and liver capsule by CO₂ [83]. It typically lasts one to three days, but can occasionally last up to seven days [84].

Postoperative shoulder pain is most correlated with the amount of retained intra-abdominal CO₂ at the end of the procedure, thus active removal of the gas by suctioning, pulmonary recruitment maneuver by anesthesia, or saline instillation may help minimize postoperative should pain [85,86]. Intraoperative measures to minimize pneumoperitoneum-related pain are discussed elsewhere. (See "Abdominal access techniques used in laparoscopic surgery", section on 'Minimizing access-related pain'.)

Thromboembolic events — Prolonged operative time and elevated intra-abdominal pressures can also lead to venous thrombotic or thromboembolic events. Following sleeve gastrectomy where the gastric blood supply is altered, there is also an elevated risk of portomesenteric venous thrombosis [87]. Patients should have their risk reduced with, at a minimum, sequential compression devices [88], and potentially perioperative chemoprophylaxis for higher risk cases [89]. Extended chemoprophylaxis may be recommended for the highest risk patients and procedures [88]. (See "Bariatric operations: Early (fewer than 30 days) morbidity and mortality", section on 'Venous thromboembolism'.)

If a patient develops thrombosis, treatment algorithms are reviewed elsewhere. (See "Overview of the treatment of proximal and distal lower extremity deep vein thrombosis (DVT)".)

COVID-19 precautions — Open and minimally invasive surgery can both produce aerosolized particulate. Previous research has shown that laparoscopy can pose a threat to surgeons and other operating room personnel by aerosolization of bloodborne viruses, including HIV (human immunodeficiency virus), hepatitis B virus, and human papillomavirus [90].

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is causing the coronavirus disease 2019 (COVID-19) pandemic, has been identified in the blood and feces [91] of infected patients and smoke/aerosol/plume generated from surgical procedures [92]. Although some studies failed to detect the virus in peritoneal fluid [93], surgical plume [94], or abdominal or adipose tissue samples [95] of patients with active COVID-19 infection, at least one report has detected, by reverse transcriptase–polymerase chain reaction, the SARS-CoV-2 virus in the peritoneal fluid of a patient who underwent emergency abdominal surgery, and the viral load in the peritoneal fluid was higher than that detected in the upper respiratory material from the same patient [96]. (See "COVID-19: Epidemiology, virology, and prevention".)

A 2022 systematic review and meta-analysis organized by the Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) found limited evidence defining any difference in patient and operating staff outcomes between laparoscopic and open abdominal surgery in COVID-positive patients [97]. Based on that, the SAGES guidelines suggest that it is safe to use either minimally invasive or open techniques (at surgeons' discretion) to treat the surgical patient who is infected with SARS-CoV-2.

In communities where SARS-CoV-2 infection is prevalent, the American, European, and Canadian societies for laparoscopic surgeons have suggested that symptomatic patients be tested for SARS-CoV-2 infection, smoke plume generated by electrosurgery be minimized, devices be used to filter released carbon dioxide for aerosolized particles, and personnel attending laparoscopic procedures be protected at minimum by N95 masks and face shields, among other personal protective equipment [98-100]. Additional information on smoke evacuation and filtration systems can be found elsewhere [101,102]. These recommendations are also consistent with those of the Royal College of Obstetricians & Gynaecologists [103] and the American College of Surgeons [104].

As there can be serious consequences of perioperative SARS-CoV-2 infection, the AAGL [98] and SAGES/European Association for Endoscopic Surgery (EAES) [99] also recommend that such patients be treated medically and invasive procedures be deferred until the SARS-CoV-2 infection has been fully treated, if possible [105,106]. (See "COVID-19: Perioperative risk assessment, preoperative screening and testing, and timing of surgery after infection".)

Gas embolism — A minimal amount of carbon dioxide diffusing into the capillary system during laparoscopy is clinically irrelevant. Gas embolism through an open large retroperitoneal vessel or a hepatic vein is a rare complication (0.15 percent) but can cause serious morbidities or mortality [23]. Gas embolism is most often reported in laparoscopic liver surgery with 10 times the incidence of other laparoscopic procedures (1.2 to 4.6 percent) [107,108], but has also been reported in other laparoscopic procedures [109].

Gas embolism should be suspected when there is sudden decrease in end-tidal CO₂ and SpO₂, hemodynamic deterioration, electrocardiographic changes, or cardiac arrest during laparoscopic surgery [110].

If gas embolism is suspected, the surgeon should flood the exposed vasculature with saline and decrease insufflation pressure while the anesthesiologist provides hemodynamic support by administrating intravenous fluids, vasopressors, and 100 percent oxygen [109]. The patient should be placed in the Trendelenburg or the Durant (Trendelenburg plus partial left lateral decubitus) position, which facilitates the release of the air from the right ventricular outflow tract. Hemodynamically unstable patients who are refractory to other management interventions and who have a pulmonary artery catheter in situ may benefit from air aspiration via the catheter.

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Laparoscopic and robotic surgery" and "Society guideline links: Biliary complications following surgery".)

SUMMARY AND RECOMMENDATIONS

●Overview – The overall rate of complications of laparoscopic surgery is low. About half of all complications related to laparoscopic surgery occur during abdominal access; other complications occur during abdominal insufflation and tissue dissection. (See 'Introduction' above and 'Epidemiology and risk factors' above.)

●Risk factors for complications – Risk factors for complications include prior surgery/abdominal adhesions, complex surgery, poor cardiopulmonary reserve, and surgeon inexperience. (See 'Risk factors' above.)

●Vascular injuries – The overall reported rate of vascular injury (arterial or venous injury) ranges from 0.1 to 6.4 per 1000 laparoscopies. (See 'Vascular injuries' above.)

•Access-related injuries to major vascular structures (aorta, vena cava, and the iliacs) are rare but potentially life-threatening. When major vascular injury is identified, consultation with a vascular or trauma surgeon should be obtained without delay. (See 'Major vessels' above.)

•Access-related injuries to minor vascular structures are more common. Among these, laceration of the inferior epigastric artery during placement of a secondary trocar is most common. When minor abdominal wall vessel injury is unrecognized, an abdominal wall hematoma may occur, most of which can be managed conservatively. (See 'Minor vessels' above and 'Inferior epigastric vessels' above.)

•Nonaccess-related vascular injuries can also during tissue dissection. Mechanical compression and application of topical hemostatic agents are appropriate initial strategies. Moderate bleeding during laparoscopic surgery can be controlled with clips, suture ligation, or electrosurgical methods. Severe or refractory bleeding requires conversion to open surgery. (See 'Dissection-related vascular injuries' above.)

●Bowel injuries – Injury to the gastrointestinal tract occurs in 0.03 to 0.65 percent of patients undergoing laparoscopic surgery, about half of which occur during initial abdominal access and the other half occur subsequently due to electrocautery or tissue trauma during dissection. The small bowel is the most commonly injured gastrointestinal structure, followed by the colon, stomach, and liver. About 30 to 50 percent of bowel injuries are not detected during initial surgery. Any patient who does not gradually improve or who continues to have abdominal pain following laparoscopic surgery should be evaluated for possible missed gastrointestinal injury. (See 'Bowel injuries' above and 'Dissection-related bowel injuries' above.)

●Urinary tract injuries – Injury to the bladder most commonly occurs during abdominal access. A history of prior pelvic surgery increases the risk of bladder injury. The risk of bladder injury can be minimized by catheterizing the patient prior to the procedure. Both the bladder and ureter can be injured during subsequent tissue dissection. A prophylactic ureteral stent may reduce ureteral injury if a difficult pelvic dissection is anticipated. (See 'Entry-related bladder injuries' above and 'Dissection-related urinary tract injuries' above.)

●Surgical site complications – Other complications of laparoscopic surgery include surgical site infection, port/extraction site hernia, port site metastasis, and peripheral nerve injury due to patient positioning or lateral trocar insertion. (See 'Surgical site complications' above.)

●Pneumoperitoneum-related complications – Complications related to insufflation of gas needed to create pneumoperitoneum include subcutaneous emphysema, mediastinal emphysema, pneumothorax, cardiac arrhythmia, carbon dioxide retention, postoperative shoulder pain related to retained intra-abdominal gas, and gas embolism due to venous injury. (See 'Related to pneumoperitoneum' above.)

ACKNOWLEDGMENTS — The UpToDate editorial staff acknowledges Jin Yoo, MD, and Gerald Gracia, MD, who contributed to an earlier version of this topic review. The UpToDate editorial staff also thanks Jon Gould, MD, Todd A Ponsky, MD, and Jeffrey Blatnik, MD, for their contributions to the "Dissection-related vascular injuries" section.