27. Decision to Convert to Open Methods
Valerie J. Halpin, M.D.
Nathaniel J. Soper, M.D.
A. Conversion Versus Complication
1. Definitions
a. Elective conversion is defined as a laparoscopic case that is opened in the absence of a complication. Elective conversion should NOT be considered a complication of laparoscopic surgery.
b. Emergent conversion is defined as a laparoscopic case that must be converted to an open approach because of the development of a complication that cannot be adequately managed using laparo- scopic techniques.
c. Complications are defined as unintentional events occurring intraoperatively that require additional maneuvers to correct and/or increase the risk of a poor outcome.
d. The reported conversion rates of commonly performed laparo- scopic procedures vary greatly (Table 27.1). The right-hand column includes the estimated number of cases in a surgeon’s learning curve. If a surgeon is learning under the supervision of another trained laparoscopist, the learning curve is shorter and generally requires fewer cases. Most publications have demon- strated that conversion rates decrease after the initial learning curve to the lower numbers in the conversion rate column. Some authors have found that their conversion rates remain relatively constant due to their selection of straightforward, technically simple cases early on in their experience with a particular proce- dure. More challenging cases are attempted only after gaining experience.
2. Effect of conversion on complication rates
a. Laparoscopic cholecystectomy. Recent data by Thompson com- paring laparoscopic to open cholecystectomy have shown that the complication rate is independent of the approach when analyzed on an intention to treat basis in three cohorts of patients (group one, open cholecystectomy; group two, laparoscopic cholecys- tectomy with 5.8% conversion rate; group three, laparoscopic cholecystectomy with 1.2% conversion rate). This observation remained true even in group three where the conversion rate
approached 1%. The severity of complications was comparable in all three groups. Notably, the converted patients in group two did have a higher complication rate than the entire group of open patients but these two groups cannot be considered equivalent in disease severity.
b. Laparoscopic nephrectomy. Data by Keeley on laparoscopic nephrectomy have shown that complication rates are more likely related to diagnosis rather than operative approach.
c. Laparoscopic colectomy. Converted patients experience longer operating times and longer hospital stays than laparoscopically completed patients. There are insufficient data in the literature to assess the complication rates of laparoscopic and converted col- orectal procedures when analyzed on an intention-to-treat basis.
d. Given this information, the surgeon, when faced with a difficult operation, should feel justified in converting to an open approach rather than risk a serious complication such as a bile duct injury with much greater clinical consequences.
B. Preoperative Factors Affecting Conversion to Open Surgery
Ideally, it would be possible to accurately predict which patients are highly likely to require conversion for a given laparoscopic operation. This subgroup, once identified, would be advised to undergo an open procedure. There are many Table 27.1. Conversion rates in commonly performed laparoscopic cases.
Number of cases in
Procedure N Conversion rates learning curve
Cholecystectomy 100 <1%–10% 30–50
Acute cholecystitis 100 5%–40%
Colorectal operations 50 1%–40% 15–50
Diverticulitis 50 4%–61%
Crohn’s 25 5%–25%
Cancer 100 4%–25%
Antireflux surgery 50 0%–10% 15–50
Inguinal hernia repair 100 1%–8% 30–50
Splenectomy 25 1%–18% 20–50
Adrenalectomy 25 0%–20% 10–20
Nephrectomy 50 5%–14% 10–50
Gastric bypass 25 0%–10% 10–50
Appendectomy 100 <1%–23% 20
Peritonitis 0%–25%
N is the minimum number of patients in series included in analysis of conversion rates.
studies concerning a variety of laparoscopic procedures that have addressed this issue.
1. Laparoscopic cholecystectomy. Investigators have attempted to iden- tify risk factors associated with a high rate of conversion. The results of these studies have been variable; however, most suggest that pre- operative factors are, in general, not reliable predictors of conversion.
Many different factors have been analyzed:
a. The presence of acute cholecystitis at the time of the surgery has been associated with higher conversion rates in multiple studies.
b. A previous history of cholecystitis, often elicited in older patients, may be associated with the operative findings of a densely adherent gallbladder and a foreshortened cystic duct. In patients without a clear history of cholecystitis, a history of more than 10 attacks of biliary colic may indicate the presence of unrecognized chronic cholecystitis.
c. Some studies have found that male gender is a predictor of higher conversion rates. The reason(s) for this are unclear; it is possible that males may neglect their symptoms for a longer period of time than females and, therefore, present with more inflammation.
d. Age greater than 65–70 years has not consistently been associ- ated with increased rates of conversion.
e. Leukocytosis has been shown, in some studies, to predict higher conversion rates, particularly in patients with acute cholecystitis.
f. It was once widely held that it was best to delay surgery for acute cholecystitis once the “golden” 72- to 96-hour window had passed. The literature suggests that this may not be the case.
g. The impact of obesity on conversion has been variable. Some authors have postulated that obesity may increase the operative difficulty early in the experience of the surgeon or when proper instrumentation is not available. Problems associated with obesity include difficult cannula placement, obscured anatomy due to excessive intraperitoneal fat, hepatic steatosis interfering with access to the subhepatic area, or difficulty with instrument manip- ulation in an excessively thick abdominal wall.
2. Laparoscopic colorectal procedures. Similar to the situation for laparoscopic cholecystectomy, there are conflicting reports in the lit- erature concerning risk factors for conversion. The following factors have been analyzed:
a. Inflammatory conditions
i. Diverticulitis: A recent meta-analysis by Gervaz identified diverticulitis as a risk factor for conversion. Several series have reported higher conversion rates with more compli- cated diverticular disease. The highest conversion rates for diverticular disease have been in the 50% range. Patient selection may also figure heavily in the determination of conversion rates. Series that report lower conversion rates may have avoided patients with complicated disease (large inflammatory masses, colovesical fistulas, etc). One series
reported a conversion rate of 18% for patients with compli- cated disease as opposed to a rate of 4.8% for uncomplicated patients.
ii. Crohn’s disease: Inflammatory bowel disease was not associated with higher conversion rates in a recent meta-analysis.
b. Surgeon inexperience (<50 cases) may be associated with higher conversion rates unless patients are very carefully selected.
c. The effect of patient age has not been consistent in all studies.
The 55- to 64-year-old age group may be at a higher risk due to a higher incidence of diverticulitis.
d. The impact of male gender on conversion is also not clear. Some authors have found increased conversion rates in males and have postulated that this finding may be due to a higher prevalence of anatomic difficulties (narrow, deep pelvis).
e. Obesity will make a technically difficult case more challenging, similar to laparoscopic cholecystectomy; however there are con- flicting data as to whether conversion rates are higher when obesity is specifically studied.
f. A diagnosis of malignancy in some colorectal resection series has been associated with a higher conversion rate. A recent meta- analysis of the literature confirms this finding. Notably, there are widely varying reports of conversion rates in oncologic laparo- scopic colorectal procedures ranging from 4% to 25%. These dis- parate results may be related to case selection. A high conversion rate would be anticipated for patients with large lesions and advanced disease.
g. Rectal resections. A review of independent reports demonstrate a fairly broad range of conversion rates in regard to rectal resec- tions. The meta-analysis by Gervaz identified anterior resection of the rectum as a risk factor for conversion. Many surgeons have been reluctant to laparoscopically pursue middle and low rectal cancers when performing a sphincter-saving procedure because it is very difficult to divide the distal rectum transversely with existing linear staples. A few authors suggest either a hand- assisted approach for these lesions or a hybrid laparoscopic and open method. The latter hybrid method includes laparoscopic proximal devascularization, splenic flexure takedown, and initial rectal mobilization followed by a planned limited inferior laparo- tomy through which the procedure is completed.
h. A logistic regression analysis by Schwander showed probabilities of conversion of 3.3%, 8.2%, 4.0%, and 5.8% in the presence of male gender, age (55–64 years), extreme body-mass index (= 27.5), and diverticular disease, respectively. If all four factors were present the probability of conversion increased to 70%.
i. A simple scoring system has been developed by Schlachta to predict conversion rates in laparoscopic colorectal procedures (Table 27.2). For 0 to 4 points, the conversion rate can be pre- dicted to be 1.1%, 3.3%, 9.8%, 25.4%, and 49.7%, respectively.
3. Laparoscopic nephrectomy. Factors that predict a more difficult operation and higher conversion rates include inflammatory condi- tions such as history of pyonephrosis, previous renal surgery, staghorn calculi, polycystic kidney disease, and xanthogranulomatous pyelonephritis
4. Laparoscopic adrenalectomy. The size of the adrenal has been shown to have an impact on the conversion rate. Large adrenals (upper size limit varying from 5 to 15 cm) are associated with a higher conversion rate.
5. Laparoscopic splenectomy. Large spleens (length greater than 30 cm and weight greater than 3200 g) and platelet count less than 35,000 have been associated with higher conversion rates.
C. Intraoperative Decision Making:
Indications for Conversion
1. Planned conversion. Failure to progress should be considered an indication to convert. Not surprisingly, the case may fail to progress in a variety of situations.
a. Adhesions from prior surgeries or from past or recent inflam- matory events are a common reason for conversion. In most patients with a history of prior abdominal surgery, the adhesions, if present, can be lysed and the case completed laparoscopically.
However, in a significant percentage, the adhesions will preclude the safe and timely laparoscopic completion of a case. Pelvic and lower abdominal adhesions, in particular, can be a problem. Most recommend placing the first port via an open cutdown well away from the site of the prior operations. If it proves very difficult to find a quadrant where there is adequate space for one or several other ports, then the patient should be converted promptly. Like- Table 27.2. Point system for predicting conversion to
open surgery in colorectal procedures.
Factor Points
Diagnosis
—Malignancy 1
—Benign disease 0
Patient weight
—<60 kg 0
—60 to <90 kg 1
—90 kg or more 2
Surgeon experience
—= 50 cases 1
—> 50 cases 0
wise, once several ports are placed, if the early adhesiolysis efforts suggest that the adhesions are very dense or extensive, then early conversion is advised. In these cases, it may be possi- ble to at least clear the abdominal wall adhesions beneath the planned incision site so that the open entry into the abdomen will be safe and rapid.
b. Acute and chronic inflammatory changes may make dissection very difficult. Inflammation may result in increased vascularity and/or dense adhesions. The extent of inflammation may preclude laparoscopic completion. In the case of laparoscopic cholecys- tectomy there may be difficulties due to cirrhosis/portal hyper- tension, a large stone in the neck, or a tethered gallbladder. It can be difficult to grasp an edematous or gangrenous gallbladder. In regard to diverticulitis or Crohn’s disease, a large inflammatory mass or especially dense adhesions to the pelvic sidewall, bladder, or gynecologic structures may make safe dissection very difficult.
Radiation-related inflammation or adhesions may also be par- ticularly difficult. There are no precise rules as to how much time to allow before converting. The surgeon should take into account the time of dissection versus the progress made as well as the remaining tasks to be completed.
c. Exposure may be poor or inadequate. Obesity may preclude placement of the ports due to an excessively thick abdominal wall. It may also prove difficult to obtain an adequate working space via pneumoperitoneum in obese patients. Last, the weight and size of the abdominal structures in some obese patients may not permit completion of a laparoscopic operation. For example, an omentum 1–2 inches thick cannot be easily lifted or reflected using the laparoscopic instruments that are available today. Minor bleeding, although not life threatening, can certainly prevent adequate visualization. Finally, in lengthy cases, it may prove difficult to maintain the pneumoperitoneum because of gas leaks around and through port incisions.
d. Altered, aberrant, or unclear anatomy. In patients who have undergone certain prior operations, the anatomy in a region may be altered such that safe laparoscopic dissection may not be fea- sible. For example, in a patient with a history of gastrectomy and retrocolic gastrojejunostomy, it may not be possible to carry out a right hemicolectomy or a transverse colectomy, which would require dissection near and around the retrocolic window. Acute inflammation, in the absence of prior surgery, may also distort or alter the anatomy. In acute cholecystitis, the cystic duct may become foreshortened with the gallbladder densely adherent to the common bile duct. The anatomy may also vary considerably for certain structures such as the cystic duct. The surgeon needs to be secure as to the location and junction of the common duct and cystic ducts. In cases of unclear anatomy, avoiding injury to the common bile duct should take precedence over avoiding laparotomy.
e. Surgeon inexperience is critical. During a surgeon’s initial expe- rience with new laparoscopic procedures, the surgeon should be selective and choose uncomplicated cases. Adequately experi- enced assistants should be secured. The surgeon’s threshold for conversion should be low while gaining experience. Once famil- iar with a given operation and having done a reasonable number of cases, the surgeon can gradually advance to more complicated cases.
f. When is the surgeon “in difficulty?” If the surgeon is unable to obtain adequate exposure or traction or “the instruments won’t do their job,” he or she should consider themselves in difficulty. In addition, if the surgeon is not sure precisely “where they are”
anatomically then they are “in difficulty.” When in difficulty, one should convert sooner rather than later.
2. Emergent conversion. Cases in which complications occur that are not manageable laparoscopically should be immediately converted to an open procedure. Severe bleeding, which may be from a major mesenteric or retroperitoneal vessel, will most often require rapid con- version. It is important to try and limit the bleeding by carefully apply- ing direct pressure to the vessel or area with a laparoscopic instrument while the laparotomy incision is made. Care must be taken not to make the problem worse by tearing or injuring adjacent structures.
Abdominal wall port wound bleeding can often be controlled without conversion (see Chapter 21 on port wound bleeding). Certain bowel injuries or other hollow viscus injury may require conversion. Simple enterotomy or colotomy can be repaired via laparoscopically placed sutures or a linear stapler. If the colotomy is in a segment of bowel to be resected, then a loop tie can be used to close the opening. A lengthy or complex bowel injury would almost always mandate conversion. In the case of laparoscopic cholecystectomy, one should convert if there is a suspected biliary injury that cannot be ruled out by cholangiogra- phy or if there is a documented biliary injury.
3. Surgeons need to recognize disease that is not appropriate for min- imally invasive methods, such as gallbladder cancer or colon cancer that invades an adjacent organ such as the kidney, spleen, or bladder.
4. Technical problems/instrument malfunction may on occasion mandate conversion. The surgeon must check that the necessary and appropriate laparoscopic equipment is available and in working order before starting the case, and that backups are available for critical pieces of equipment.
5. Anesthesia-related issues. Conversion may also prove necessary if the patient is poorly tolerating the pneumoperitoneum. Pulmonary problems such as hypercarbia, hypoxia, and the need for very high inspiratory pressures (to deliver the desired volume of gas) may mandate conversion. This is most likely to occur in patients who have a history of lung disease. Brief pneumoperitoneum “breaks” during which the abdomen is desufflated may permit completion of the case in patients in whom hypercarbia develops. Patients with marginal cardiac function may also not tolerate a pneumoperitoneum. It is
critical that the surgeon and anesthetist communicate well and often during the operation so that timely conversion can be carried out.
Please refer to the chapters concerning the cardiac and pulmonary ramifications of pneumoperitoneum as well as the anesthesia chapters for a full discussion of these issues.
D. Selected References
Fried GM, Barkun JS, Sigman HH, et al. Factors determining conversion to laparotomy in patients undergoing laparoscopic cholecystectomy. Am J Surg 1994;167:35–41.
Gervaz P, Pikarsky A, Utech M, et al. Converted laparoscopic colorectal surgery. A meta- analysis. Surg Endosc 2001;15:827–832.
Higashihara E, Baba S, Nakagawa K, et al. Learning curve and conversion to open surgery in cases of laparoscopic adrenalectomy and nephrectomy. J Urol 1998;159:650–653.
Hutchinson CH, Traverson LW, Lee FT. Laparoscopic cholecystectomy: do preoperative factors predict the need to convert to open? Surg Endosc 1994;8:875–878.
Keeley FX, Tolley DA. A review of our first 100 cases of laparoscopic nephrectomy: defin- ing risk factors for complications. Br J Urol 1998;82:615–618.
Pandya S, Murray JJ, Coller JA, Rusin LC. Laparosopic colectomy: indications for con- version to laparotomy. Arch Surg 1999;134:471–475.
Rutledge D, Jones D, Rege R. Consequences of delay in surgical treatment of biliary disease. Am J Surg 2001;180:466–469.
Schlachta CM, Mamazza J, Seshadri PA, Cadeddu MO, Poulin EC. Predicting conversion to open surgery in laparoscopic colorectal resections. Surg Endosc 2000;14:1114–
1117.
Schwandner O, Schiedeck THK, Bruch HP. The role of conversion in laparoscopic col- orectal surgery. Do predictive factors exist? Surg Endosc 1999;13:151–156.
Strasberg SM, Hertl M, Soper NJ. An analysis of the problem of biliary injury during laparoscopic cholecystectomy. J Am Coll Surg 1995;180:101–125.
Thompson MH, Benger JR. Cholecystectomy, conversion and complications. HPB Surg 2000;11:373–378.
