Complications Of Laparoscopic Surgery
This article is written with an attempt to guide physicians and lawyers through the complications of laparoscopic surgery in the hope that such complications will be avoided in the future. My concern is that the explosive growth in the number of laparoscopic surgery procedures and their diversity coupled with insufficient training by surgeons who now perform this procedure have led to many unnecessary complications.
Over the last 50 years progress in surgery was linked to the abandonment of major ablative and deforming procedures, and replacing them with simpler and safer ” minimally invasive procedures”. For example a radiologist can now drain abscesses and open blocked vessels in a mildly sedated patients where only 20 years ago the patient would have undergone major and risky procedures to accomplish the same result.
The development of “minimally invasive surgical procedures” began in the animal lab and was carefully studied in select academic centers. It was imported to the community hospitals only when its benefits and safety were established. In contrast the development of laparoscopic cholecystectomy was not designed to enhance the safety of the procedure, but rather to reduce the discomfort associated with the surgical incision. The fierce economical competition in medicine fueled by the managed care movement, led to the rapid adoption of Laparoscopic Surgery among surgeons in community hospitals who were not formally trained in this technique and acquired their knowledge by subscribing to short courses.
Laparoscopic surgery is popular with patients and insurance companies. The absence of an incision is cosmetically appealing. The immediate post operative course is smoother, allowing for early discharge from the hospital and early return to work. The procedure however is surgically demanding and introduces specific risks unique to the laparoscopic surgery that are not present during the performance of procedures like open cholecystectomy. While the goal of minimizing the immediate post operative morbidity is laudable, the patient, at the very least, should be entitled to the same safety record associated with open procedures.
Alarmed by a series of severe and unusual complications reported after laparoscopic cholecystectomy, the New York State department of health conducted a thorough review of this practice. 158 serious complications were identified comprising of major vessel laceration, hemorrhage, bile leak , and bowel perforation. In contrast only 23 such complication were identified following open cholecystectomy. The rate of injury to the bile duct was 15 times higher when cholecystectomy was performed laparoscopically than if open cholecystectomy was performed.
The New York panel concluded that as long as complications from laparoscopic surgery exceed the complication rate of open procedures, laparoscopic surgery cannot be considered at present the state of the art. It is hoped that laparoscopic surgery performed by well trained surgeons will attain in the future the same safety record of the open procedure it attempts to replace.
Laparoscopic surgery was developed by gynecologists in the 1960s as a diagnostic tool. The procedure was gradually extended to allow minor surgical interventions, usually in fertility surgery, and usually on young healthy patients. In 1984 Reddick first applied the technique to laparoscopic cholecystectomy. The procedure became extremely popular among patients, mostly young and healthy, who were able to return to work within few days after the procedure.
By 1991 more than 10,000 laparoscopic cholecystectomy cases were reported. In the last 5 years laparoscopic surgery has been extended to surgery of the appendix, colon , stomach , kidney ,and liver.
Of specific concern is the fact that the experience derived over time with laparoscopic surgery was obtained primarily in young healthy patients undergoing short and limited procedures. Extension of laparoscopic surgery technique to general surgery where patients are generally older and sicker was done only in the last decade and experience is thus limited.
Data Source and Reliability
Several retrospective studies reported that the morbidity and mortality of laparoscopic surgery is comparable to open cholecystectomy. These retrospective studies ,however, tend to underestimate the true incidence of complications related to laparoscopic cholecystectomy. When prospective studies were conducted they have shown considerably higher complication rates than the retrospective studies reported.
As the majority of procedures are now being done in community hospitals rather than academic centers, these studies rely heavily on voluntary reporting by many individual practitioners. Survey by the association for gynecologic laparoscopic surgery, reported that only 20-40% of surgeons responded to the survey . One can safely assume that individual surgeons will tend not to volunteer their complication rate.
Low complication rates were reported by centers specializing in laparoscopic surgery, mostly in academic centers. These centers were able to reduce the complication rate to minimum by developing proficiency in this surgery. Regrettably many inexperienced surgeons perform this technique with insufficient training and are responsible for the majority of complications seen during the performance of laparoscopic surgery.
Physicians who performed less than 100 such procedures reported 14.7 complication per 1000 patients. In contrast experienced surgeon reported a complication rate of only 3.8 complications per 1000 procedures . The Southern Surgeons Club Survey reported that the incidence of bile duct injury was 2.2% when the surgeon had previously performed less than 13 procedures. As surgeons gained experience the incidence of bile duct injury dropped to 0.1% afterwards.
An index to the true complication rate associated with laparoscopic cholecystectomy comes from radiologists in tertiary care centers to whom patients with bile duct injury are referred. In one such study radiologists reported that damage to the common bile duct during laparoscopic surgery occurred in 2.8% of the cases- almost 3 times the rate reported for open cholecystectomy .
Clearly prospective studies and mandatory reporting is needed to allow comparison between open cholecystectomy and laparoscopic surgery
The Laparoscope is a metal tube inserted into the abdominal cavity of the patient for the purpose of visualizing the abdominal organs and as a mean for surgical intervention.
The Laparoscope is equipped with a camera that provides visualization as well as a mean to record the operation on a video cassette. Laparoscopic Surgery begins by placing a specialized needle – The veress needle- into the abdominal cavity and filling the abdominal cavity with gas. CO2 is the preferred gas as it is absorbed readily and is excreted by the lungs. Intra abdominal pressure of 12-15 mmHg is usually required to maintain the gas in the abdominal cavity.
Insertion of a sharp metal cylinder the Trocar follows. The Laparoscope, equipped with camera, is thus introduced into the abdominal cavity. A second and third trocars are then inserted. This insertion is now guided by the laparoscope inserted through the first insertion site. A myriad of instruments can be inserted through the laparoscope, and used to dissect, tie, clip, or cauterize blood vessels. The secondary cannula ports are used for retractors and “grasper” which retract tissue, and for irrigation-suction devices.
Veress Needle and Trocar Injuries
The Veress Needle and the trocar are unique to laparoscopic surgery. They are inserted blindly, and can easily cause bowel or vascular injury. Vascular injuries including perforation of the aorta and iliac vessels were reported in up to 0.6% of the cases, 10% of them serious. Some fatalities were reported and trocar perforation of a blood vessel is second most often reported cause of death after anesthesia. Unlike open procedure where vascular injury is immediately recognized, in laparoscopic surgery ,vascular injury may not be recognized till the patient is in shock
A dreaded complication associated with vascular injury is gas embolization. The insufflated CO2 gas can enter the heart through a rent in a blood vessels. Gas embolism resulting in death , and near death incidents were reported. Usually the presentation is immediate and dramatic but may also be noted 30 minutes later when gas enters the portal system.
Bowel injuries , some fatal, were reported in 4/1000 cases. These included injuries to stomach, small bowel, colon and spleen. Misplacement of the Veress needle can cause pneumothorax – the entry of air into the lung lining leading to compression of the lung, lung collapse, hypoxemia and hypotension. Gas may escape into the lung lining by trocar injury to the diaphragm or the persistence of a congenital opening through the diaphragm. The reader must note that none of these dreaded complications occurs in the course of open laparotomy where veress needle, trocars, and gas insufflation are not used.
The following measures were reported to reduce the incidence of trocar injuries:
1) Disposable laparoscopes are usually sharper. They require less force to insert and thus there is less chance of compressing the trocar against the bowel or blood vessels.
2) Some manufacturers provide a plastic sheath which springs and cover the sharp edge of the trocar after insertion. Safety shields will not prevent injury however in case of bowel adhesions.
3) The use of ultrasound to “map” the abdominal wall for safe entry area is recommended especially when adhesions are present.
4) The smaller – 5mm cannula – is safer as it requires less pressure to insert. Equipped with a camera it allows safe placement of the larger cannula under vision.
5) Hasson described an open surgical approach to placement of the cannula thus reducing the risk of perforation by the blind closed technique.
6) Before the conclusion of surgery, a thorough search for bowel injuries must be performed as delay in recognition of such injury can be catastrophic. Thus review of the video tapes can ascertain if safety measures were taken during this critical part of the procedure.
Unlike open surgery where hemostasis (control of bleeding) is accomplished by pressure and careful application of fine clamps and ligatures, laparoscopic surgery must rely on electrocautery to achieve hemostasis. Excessive cautery can burn a hole in the wall of the organ involved. Cautery can also cause injury to adjacent organs, and even distant organs.
In addition to direct burn by the cautery needle, smoke associated with electrocautery may allow sparking and its attendant damage to nearby bowel wall. Such damage is unlikely to occur during open laparotomy for several reasons. During open laparotomy the bowel is well protected by laparotomy pads, smoke readily dissipate to the well ventilated room, and any bowel adjacent to the burnt area can be inspected to assure that no damage has occurred. In contrast, in laparoscopic surgery, the bowel cannot be protected, and bowel inspection is inefficient due to the limited field of view offered by the camera.
Of specific concern is electrocautery near the bile duct. The bile duct is a duct filled with fluid and thus acts like an electric cable. The current directed against a bleeding artery often travels, instead, down the duct dissipating the electric current. To achieve hemostasis surgeons often increase the current. Higher current, however, often leads to damage to the common bile duct. In addition like any electric burn, current preferentially traveling along the fluid filled duct, may also burn the duodenum adjacent to the duct. .
In addition to acute perforation of the common duct, cautery can cause delayed injuries. Meyer reviewed 12 cases of delayed manifestation of common duct injuries and commented that cautery of the duct resulted in fibrosis and ultimately with bile duct stricture.
Damage to bowel was also seen during laparoscopic laser surgery. CO 2 laser has the least amount of depth penetration but as it offers a poor control of bleeding it is applied for a longer period of time leading to injury. The limited control of the operative field in laparoscopic surgery as compared to open cholecystectomy may result in inadvertent injury to the bowel by “past pointing” – the surgeon may be pushing the trigger a split second away from the target resulting in an unintended burn. Even unrecognized contact of the bowel with the tip of Laparoscope outside of the visual field may result in bowel wall damage.
The two – dimensional view of the TV screen unlike three – dimension view of open laparotomy, restricts the capacity to appreciate the depth of field and thus to be able to observe the entire cautery needle during its use. This limitation may result in contact between the electrode and adjacent bowel not appreciated during surgery. A small burn of the bowel wall during open laparotomy can be easily detected and repaired with minimal morbidity. In contrast a small but undetected burn of the bowel wall which occurs during laparoscopy is easily overlooked. The burnt area is sloughed in 5 days resulting in delayed perforation of the bowel which is sometimes fatal
Here again inspection of the entire field is of paramount importance. Bowel burn that is unrecognized will lead to perforation when the desiccated cells are shed off. The burn area is often much larger area than visible during surgery, and bowel resection may be necessary.
Laparoscopic surgery requires the insufflation of CO 2 into the abdominal cavity.
Complications associated with CO 2 insufflation include:
1) Escape of CO 2 into the heart or pleural cavity
2) Effects of the resultant increased intra abdominal pressure on cardiac, renal and liver physiology
3) Effects of the absorbed CO 2 on cardio-respiratory function
The fatal complication of CO 2 embolization to the heart and lung were discussed earlier . CO 2 is insufflated under 12-15 mm. Hg pressure to elevate the abdominal wall and allow the camera the necessary distance to the organ operated on. Depending on the intra abdominal pressure used and the position the patient is placed – head up or head down – several potential harmful physiologic derangements may occur.
combination of high intra abdominal pressure and head up position used in Gynecological surgery increases blood return to the heart. This rapid “auto-transfusion ” may overwhelm the heart capacity to receive and pump out the blood leading to heart failure in patients with compromised hearts .
High intra abdominal pressure coupled with head up position, as frequently done during laparoscopic cholecystectomy, result in pooling of blood in the legs, reduced venous return, hypotension, and increased tendency to develop venous thrombosis. .
In addition to the pressure effect of the gas insufflated, CO 2 may have direct effect on the heart and lung when absorbed into the blood stream. Desmond reported increased arterial p CO 2 and decreased Ph from absorption of the instilled CO 2 to the blood. The increased arterial pCO 2 resulted in arrhythmia ( abnormal heart rhythm) in up to 97% of patients undergoing laparoscopic surgery .
In addition to the direct effect of CO 2 on the heart, CO 2 stimulates the release of several hormones that adversely effect the heart. These include plasma Catecholamine usually released during stress, Vasopressin which affect the liver circulation, and other mediators causing Vaso-vagal stimulation of the heart . The combined release of these harmful mediators is responsible for the circulatory collapse seen during Laparoscopic Surgery.
Open Surgery allows the surgeon full control of the operative field. Retractors and pads protect adjoining organs, and tactile sensation is maximized. In contrast Laparoscopic surgery offers an extremely limited view of the field. The loss of three dimensional depth perception , the limited view offered by the camera, the loss of tactile perception, and the difficulty in controlling minor bleeding render this procedure much more demanding than comparable open procedures.
The most dreaded complication in laparoscopic cholecystectomy is damage to the bile duct. The New York department f health reported 15 fold increase in bile duct injury when laparoscopic cholecystectomy was performed. Injury to the bile duct even if recognized and repaired, frequently leads to fibrosis and narrowing of the duct. The increased biliary pressure in turn leads to frequent liver infections, cirrhosis of the liver, and death.
The specific technical differences in dissection of the biliary tree between the open and closed procedures, are beyond the scope of this article. It is sufficient to state the recognition of the junction between the cystic duct and the common bile duct is the key to prevention of bile duct injury. During open cholecystectomy the surgeon can grab the gall bladder, easily identify the junction of the cystic duct and the gall bladder and trace the cystic duct towards the common duct then the T junction of the cystic duct entry to the common duct is demonstrated at right angle ( as permitted by the open technique) dissection stops. Such recognition of the common duct is far more difficult in laparoscopic surgery. The gallbladder and cystic duct cannot be reflected medially to form a right angle position to the common duct, thus allowing identification of the proximal part of the common duct. Instead the surgeon needs to dissect the junction initially a difficult dissection that can lead to mistaken ligation of the common bile.
The following are measures designed to reduce common bile duct injury:
1) Laparoscopic surgery must be done only by experienced well supervised surgeons
2) Surgeon who performed less than 100 laparoscopic surgery procedures should screen their patients very carefully for indication to perform this procedure, and should not attempt this procedure initially in patients with adhesions from previous surgery and in acute cholecystitis.
3) Whenever in doubt, conversion to open surgery is indicated. Currently reported rate of conversion is 4-5%. And failure to abort a difficult laparoscopic surgery and convert to open and safer surgery may be considered as departure from the standard of care especially in cases performed by relatively inexperienced surgeons .
4) Intra-operative cholangiography is helpful in “mapping” the biliary tree and add another measure of safety
5) Wide angle camera angle lenses and several ports can enhance the safety of the procedure
Laparoscopic surgery is associated with decreased immediate post operative discomfort. Patients are often discharged from the hospital and resume their regular activities early. Centers with expertise in this field continue to improve the safety of the technique. However laparoscopic surgery performed by poorly trained surgeon remains a major hazard.
In evaluating laparoscopic surgery complications one needs to recall that the technique replaces an open procedure with extremely low rate of mortality and morbidity. Laparoscopic surgery introduces risks such as trocar injury, cardiovascular problems and damage to bowel and major vessels that are rarely if ever encountered in open cholecystectomy.
I believe that laparoscopic surgery by inexperience surgeons should be discouraged and that hospitals have a duty to credential , supervise, and track the performance of laparoscopic surgery in their operative facilities. Video cassettes recorded during surgery offer an excellent way to assess whether a complication was the result of negligence. Analyzing such tapes will identify the causes for the complications noted and suggest ways to avoid them. In this regard it is vital for both lawyers – protecting their clients safety, and surgeons – interested in improving the surgical techniques, to work together to define the role appropriate for this technique.