Consequences of Conversion inLaparoscopic Colorectal SurgeryRodrigo Gonzalez, M.D.,1 C. Daniel Smith, M.D.,1 Edward Mason, M.D.,2

Titus Duncan, M.D.,2 Russell Wilson, M.D.,2 Jacqueline Miller, M.D.,2

Bruce J. Ramshaw, M.D.3

1 Emory Endosurgery Unit, Emory University School of Medicine, Atlanta, Georgia2 Department of Surgery, Atlanta Medical Center, Atlanta, Georgia3 Division of General Surgery, University of Missouri, Columbia, Missouri

INTRODUCTION: Laparoscopic procedures converted toopen approaches have been associated with higher com-plication rates than laparoscopic and open cholecystecto-my and appendectomy. Laparoscopic colorectal resectionshave relatively high conversion rates compared with otherlaparoscopic procedures. This study was designed toevaluate outcomes of conversions compared with laparo-scopic and open colorectal resections. METHODS: Wereviewed 498 consecutive colorectal resections performedbetween 1995 and 2002. Procedures were divided intolaparoscopic colorectal resections, open colorectal resec-tions, or conversions. Demographics, underlying disease,type of procedure performed, and operative outcomeswere compared between groups. RESULTS: Of the 238laparoscopic procedures performed, 182 were completedlaparoscopically and 56 (23 percent) required conversion;260 were performed open. Conversions were associatedwith greater blood loss (200 (range, 50–750) vs. 100(range, 30–900) ml), longer time to first bowel movement(82 (range, 40–504) vs. 72 (range, 12–420) hr), and longerlength of stay (6 (range, 2–67) vs.. 5 (range, 2–62) days)than the laparoscopic colorectal resections group. Therewas no difference in operative time, transfusion require-ments, intraoperative and postoperative complications, ormortality between conversions and laparoscopic colorectalresections. Conversions resulted in fewer patients requiringtransfusions (4 vs. 14 percent), shorter time to first bowelmovement (82 (range, 40–504) vs. 93 (range, 24–240) hr),and shorter length of stay (6 (range, 2–67) vs. 7 (range, 2–

180) days) than in the open colorectal resections group.There were no differences in complications or mortalitybetween the conversion group and the open colorectalresections group. CONCLUSIONS: Laparoscopic colorectalresections has a relatively high conversion rate; however,the converted cases have outcomes similar to opencolorectal resections. In fact, the converted group requiredfewer blood transfusions than the open group. Experienceand good judgment are fundamental for timely conversionof a laparoscopic procedure to open to decrease complica-tion rates. Despite a high conversion rate, surgeons shouldconsider laparoscopic colorectal resections, because evenwhen necessary, conversion does not result in poorer out-comes than laparoscopic colorectal resections or opencolorectal resections. [Key words: Laparoscopy; Colorectalsurgery; Conversions; Complications; Laparotomy]

T he minimally invasive approach for colorectal

resections was introduced more than a decade

ago. Some of the benefits described for the laparo-

scopic approach include less blood loss, reduced

stress because of the diminished surgical trauma, less

postoperative pain, faster return of bowel activity,

shorter length of hospital stay, and lower complica-

tion rates (particularly those of infectious nature)

compared with the open technique.1–6 However,

there has not been a widespread acceptance of this

technique despite various series reporting benefits

over the traditional approach for colorectal resec-

tions. One reason for this is that laparoscopic colon

resection is a technically challenging procedure.

The learning curve reported for laparoscopic

colorectal resections (LCR) has been estimated to be

in the range between 30 and 100 procedures.7,8 It is

Presented at the meeting of the International Congress and EndoExpo-SLS, Las Vegas, Nevada, September 22 to 25, 2003.

Correspondence to: Bruce J. Ramshaw, M.D., MC44 McHaneyHall, One Hospital Drive, Columbia, Missouri 65212, e-mail:bramshaw98@yahoo.com

Dis Colon Rectum 2005; 49: 197–204DOI: 10.1007/s10350-005-0258-7* The American Society of Colon and Rectal SurgeonsPublished online: 04 December 2005

197

considered one of the longest learning curves for

laparoscopic procedures.8,9 The odds ratio for factors

associated with increased risk for conversion are

as follows: right hemicolectomy (0.668), left hemi-

colectomy (1.061), anterior resection (1.088), inflam-

matory bowel disease (0.995), adenoma (1.014),

diverticulitis (1.302), and carcinoma (2.944).9

One of the parameters most commonly assessed

when studying the learning curve of a procedure is

the decrease in the conversion rate over time. LCR

has been reported to have a relatively high conver-

sion rate compared with other laparoscopic proce-

dures, reported between 1.9 and 40 percent.9 It also

has been described that as surgeons acquire experi-

ence in LCR, there is a reduction in the conversion

rate, operative time, and complication rates.8,10

Understandably, many of the advantages of the

laparoscopic approach are lost when a procedure is

converted, because the need for a larger incision

makes the outcomes more closely resemble those of

an open technique. Therefore, it is not surprising to

find that converted laparoscopic procedures have

higher rates of complications, with a prolonged hos-

pitalization and convalescence period, compared with

laparoscopic procedures. In fact, conversion during

laparoscopic cholecystectomy11 and appendectomy12

has been associated with higher complication rates

compared with those of the open approach. If this is

true for a procedure with a relatively high conversion

rate, such as LCR, changes in the treatment strategies

may have to be implemented for LCR. This study was

designed to evaluate outcomes of converted proce-

dures compared with those of laparoscopic and open

colorectal resections (OCR).

METHODS

This study was approved by the Institutional Re-

view Board of Emory University School of Medicine.

A retrospective chart review of all patients who un-

derwent colorectal resection between January 1995

and July 2002 at a teaching hospital was conducted.

Both benign and malignant diseases were included

in the study. Only patients who underwent a colo-

rectal resection were included. All patients who only

underwent a laparoscopic exploration or a colonic

diversion without resection were excluded from the

study. Surgeons in this series were directly involved

in all types of operations and provided similar num-

ber of patients. Our end point was to evaluate the

impact of converting a surgery to open; we reviewed

all patients to include the learning curve of laparo-

scopic colorectal procedures of all surgeons.

Depending on the approach, patients were divided

into LCR and OCR groups. Patients in the LCR group

were further divided into two groups according to

the need for conversion during the operation: colo-

rectal resection completed laparoscopically (LCR),

and laparoscopic colorectal resection requiring con-

version (CCR). The surgical technique was chosen on

a patient-by-patient basis using surgeons’ judgment

and experience. Conversions were defined as ex-

tending one of the incisions to perform any step of

the procedure other than the anastomosis or spec-

imen removal, or performing a formal laparotomy to

complete the operation. In the case of hand-assisted

laparoscopic surgery (HALS), extending incision of

the hand port used originally to fit the surgeon’s

hand to perform any part of the operation was con-

sidered a conversion.

Demographic data and previous medical history,

including age, gender, body mass index (BMI), his-

tory of previous abdominal surgeries, and presence

of comorbidities were assessed. Surgical procedures

were divided into left colectomy, right colectomy,

transverse colectomy, sigmoidectomy, subtotal colec-

tomy, total proctocolectomy, low anterior resection

(LAR), and abdominoperineal resection (APR). Op-

erative data evaluated included operative time, intra-

operative complications, estimated blood loss (EBL),

and transfusion requirements. Complications that

occurred in procedures not requiring conversion

were included in the LCR group. To evaluate con-

versions in their entire context, all intraoperative

complications that occurred before or after a conver-

sion were included in the CCR group. Procedures

that were initiated laparoscopically and included the

HALS technique, without extending the hand inci-

sion, were included in the LCR group. Postoperative

data collected included time to first bowel movement

(bowel movement), length of hospital stay (LOS),

and complications. Data were analyzed and com-

pared between the three groups.

Statistical Analysis

Continuous parametric data were analyzed using

one-way analysis of variance or Student’s t-test. Non-

parametric data were analyzed using Mann-Whitney

U test. Categoric data were analyzed using Fisher’s

exact test. Normally distributed data are reported as

mean T standard error of the mean; data not normally

198 GONZALEZ ET AL Dis Colon Rectum, February 2006

distributed are reported as median (range). P < 0.05

was considered statistically significant.

RESULTS

Between January 1995 and March 2002, a total of

498 colorectal resections were performed in our

institution. The laparoscopic approach was attemp-

ted in 238 patients and the open technique was

performed in 260 patients. Of the procedures

approached with the minimally invasive technique,

182 were completed laparoscopically and 56 (23

percent) required conversion. Fourteen cases were

initiated with the HALS technique. Eight of the

laparoscopic cases were transformed to HALS and

were included in the LCR group. Extension of the

hand-port incision was used to complete the opera-

tion in four patients who, therefore, were included in

the CCR group. The indications for conversion

included inadequate exposure in 25 patients (45 per-

cent), cancer in 20 patients (40 percent), obesity in 7

patients (13 percent), bleeding in 4 patients (7 per-

cent), enterotomy in 4 patients (7 percent), general-

ized peritonitis in 1 patient (2 percent), anesthesia

problems in 1 patient (2 percent), stapling device

failure in 1 patient (2 percent), and difficulty per-

forming an adequate anastomosis in 1 patient

(2 percent). An intraoperative complication was the

reason for conversion in ten patients (18 percent).

There was no difference in the percentage of patients

requiring transfusions, postoperative complications,

or 30-day mortality rates between the patients in

whom the procedure was converted because of

complications and patients without complications

before the conversion (Fig. 1).

The wide variety of indications for the colorectal

resections is summarized in Table 1. The most common

indication for colorectal resection in the open group

was cancer. Diverticular disease was the most common

indication in the LCR group. The conversion rates

according to the underlying disease are as follows:

bowel obstruction (43 percent), inflammatory bowel

disease (36 percent), cancer (35 percent), volvulus

(25 percent), ischemic bowel (25 percent), diverticular

disease (22 percent), polyps (6 percent), colonic inertia

(0 percent), and complicated appendicitis (0 percent).

Patients in the three groups were matched for

age and gender (Table 2). There was no significant

difference between groups in the number of patients

with previous abdominal surgeries and presence of

comorbidities. The laparoscopic approach was suc-

cessfully completed even in patients with up to five

previous abdominal surgeries (Table 2). The conver-

sion rate decreased from 38 percent in the first 50 pro-

cedures to 12 percent during the last 50 procedures.

The type of procedure performed was similar

between groups (Table 3). The most common proce-

dure approached with both the open and laparoscop-

ic techniques was a right hemicolectomy, followed by

sigmoidectomy and left hemicolectomy. The conver-

sion rates according to type of procedure performed

were as follows: left hemicolectomy (29 percent), LAR

(29 percent), sigmoidectomy (25 percent), subtotal

colectomy (23 percent), right hemicolectomy (21

percent), transverse colectomy (20 percent), and total

proctocolectomy (18 percent). There were no APRs

attempted laparoscopically in this group of patients.

The LCR resulted in less EBL, fewer patients

requiring transfusions, shorter time to first bowel

movement, shorter LOS, and lower postoperative

complication rate than the open technique (Table 4).

Operative time, intraoperative complications, and

mortality rate were similar between the LCR and

OCR groups. Compared with the laparoscopic group,

the converted group resulted in a greater EBL, longer

time to first bowel movement, and longer LOS.

Operative time, intraoperative complication rate,

number of patients requiring transfusions, postoper-

ative complication rate, and mortality rate were similar

Figure 1. Comparison of perioperative complications and30-day mortality between complicated (n = 10) andnoncomplicated (n = 46) cases in the conversion groups.Complications as the reason for conversion did not resultin increased morbidity or mortality rates compared withnoncomplicated cases, although there was a trend in thatdirection.

Vol. 49, No. 2 CONVERSION OUTCOMES IN COLORECTAL SURGERY 199

between the LCR and CCR groups. Fewer patients

required transfusions, the time to first bowel move-

ment was shorter, and the length of hospitalization

was shorter in the CCR than the OCR group (Table 4).

There was no difference in operative time, EBL,

intraoperative or postoperative complications, or

mortality between the CCR and the OCR groups.

In an intention-to-treat basis (procedures complet-

ed laparoscopically plus the converted cases), the

laparoscopic technique resulted in less EBL (100

(range, 30–900) ml vs. 200 (range, 50–3,000) ml; P <

0.0001), fewer patients requiring transfusions (4 vs.

14 percent; P < 0.001), shorter time to first bowel

movement (72 (range, 12–504) hr vs. 93 (range, 24–

240) hr; P < 0.0001), shorter LOS (5 (range, 1–67)

days vs. 7 (range, 2–180) days; P < 0.0001), and lower

postoperative complication rate (15 vs. 32 percent;

P < 0.0001) than the OCR group.

Table 1.Indications for Colorectal Resections in Each of the Groups

Open (n = 260) Laparoscopic (n = 182) Conversions (n = 56) P Value

Cancer 117 (45) 42 (23) 23 (41) NSDiverticular disease 67 (26) 64 (35) 18 (32) NSPolyps 27 (10) 45 (25) 3 (5) NSInflammatory bowel disease 8 (3) 7 (4) 4 (7) NSIschemic bowel 8 (3) 3 (2) 1 (2) NSBowel obstruction 6 (2) 4 (2) 3 (5) NSColonic inertia/functional

constipation6 (2) 5 (3) 0 NS

Complicated appendicitis 6 (2) 2 (1) 0 NSVolvulus 4 (1.5) 3 (2) 1 (2) NSOther 11 (4) 7 (4) 3 (5) NS

NS = difference between groups not statistically significant.Data are numbers with percentages in parentheses.

Table 2.Demographics of Patients in Each Group

Open(n = 260)

Laparoscopic(n = 182)

Conversions(n = 56) P Value

Age (yr) 63 T 0.9 60 T 1.1 62 T 1.8 NSGender, male 108 (42) 101 (55) 29 (52) NSPrevious abdominal surgery, patients 130 (1–6) 127 (1–5) 26 (1–6) NSPresence of comorbidities, patients 160 (62) 126 (69) 33 (63) NS

NS = difference between groups not statistically significant.Data are numbers with percentages or ranges in parentheses.

Table 3.Type of Procedure Performed in Each of the Different Techniques

Open(n = 260)

Laparoscopic(n = 182)

Conversions(n = 56) P Value

Left hemicolectomy 43 (15) 29 (16) 12 (21) NSRight hemicolectomy 69 (25) 65 (36) 15 (27) NSSigmoidectomy 44 (16) 48 (26) 16 (29) NSLow anterior resection 40 (14) 17 (9) 7 (13) NSSubtotal colectomy 23 (8) 10 (4) 3 (5) NSTotal proctocolectomy 17 (6) 9 (5) 2 (4) NSTransverse colectomy 8 (3) 4 (2) 1 (2) NSAbdominoperineal resection 9 (3) 0 0 NS

NS = difference between groups not statistically significant.Data are numbers with percentages in parentheses.

200 GONZALEZ ET AL Dis Colon Rectum, February 2006

DISCUSSION

The need for conversion has been recognized in

all laparoscopic procedures. It is by itself not a

complication but may be considered by many as a

possible drawback because it eliminates the advan-

tages of a minimally invasive technique. The major

concern in the converted cases is the possible

increased risk of postoperative morbidity and mor-

tality, because two of the most common indications

for conversion include inadequate exposure or to

manage a complication.

Laparoscopic procedures converted to open are

associated with poorer outcomes than those of

nonconverted procedures; however, this may reflect

the degree of difficulty of the procedure. In the

majority of converted cases the underlying disease

is acute, challenging, or complicated, and the oper-

ation usually takes longer, therefore, increasing the

risk of intraoperative complications. In the case of

laparoscopic cholecystectomy, patients in whom the

conversion is required are usually elderly, obese, or

have had multiple previous abdominal surgeries

leading to adhesions.11,13

The most common indication for conversion in

our series was inadequate exposure, of which

bowel obstruction (i.e., adhesions, volvulus, com-

plicated diverticulitis, obstructed colon cancer, etc.)

was the most common cause. The high incidence of

conversions in these patients derives from the

perception of an unsafe procedure because of the

limited visual field and an increased risk for an

enterotomy and/or bleeding. This also may explain

why the types of procedures most commonly

converted were in the left side of the colon (left

hemicolectomy and sigmoidectomy), because the

majority of the obstructions and inflammatory dis-

orders occurred from disease processes in the left

colon.

During our early experience dealing with cancer,

all patients revealing an incidental colorectal cancer

during exploration of the abdominal cavity were

converted because of the concern of port site

metastases frequently reported in the literature at

the time. This particular issue applied to a small

number of patients who were initially explored for

other indications (i.e., partial obstruction, polyps,

diverticular disease, etc.) and a colorectal cancer was

diagnosed incidentally during abdominal explora-

tion. Latter reports demonstrated not only the safety

and efficacy of the laparoscopic approach for

colorectal cancer, but also risk of distant metastasis

similar to open surgery. Thus, we changed our

protocols and started approaching colorectal cancer

laparoscopically.

More recently, the indications for conversion in

cancer cases were tumor fixation to adjacent struc-

tures and inadequate oncologic resection. In obese

patients, the amount of fat in the mesentery makes

the visualization of vascular structures and the

mobilization of the colon more difficult. Patients with

unclear anatomy were those in which an inflamma-

tory reaction (particularly inflammatory bowel dis-

ease and complicated diverticulitis), involving the

colon and adjacent tissues, led to the structures being

indistinguishable and the dissection was considered

to be unsafe. We used the HALS technique more

frequently in the beginning of our experience of

laparoscopy for colorectal resections, and we found

it useful in the transition between open and laparo-

scopic surgery, especially to achieve an oncologic

resection in patients with cancer.

Table 4.Comparison of Operative Outcome Between Groups

Open (n = 260) Laparoscopic (n = 182) Conversions (n = 56)

Operative time (min) 135 (40–385) 150 (55–440) 155 (58–330)Intraoperative complications 18 (7) 8 (4) 5 (9)Estimated blood loss (ml)a,b 200 (50–3,000) 100 (30–900) 200 (50–750)Transfusionsa,c 36 (14) 8 (5) 2 (4)Time to first bowel movement (hr)a,b,c 93 (24–240) 72 (12–420) 82 (12–420)Length of stay (day)a,b,c 7 (2–180) 5 (2–62) 6 (2–67)Postoperative complicationsa 84 (32) 24 (13) 11 (19)Mortality 14 (3.8) 3 (1.6) 2 (3.6)

Data are numbers with percentages or ranges in parentheses.a Statistical difference between open and laparoscopic groups (P < 0.001).b Statistical difference between laparoscopic and converted groups (P < 0.01).c Statistical difference between open and converted groups (P < 0.05).

Vol. 49, No. 2 CONVERSION OUTCOMES IN COLORECTAL SURGERY 201

The indications for conversion in our study are

similar to what several series have described as

predictive factors for conversion in LCR. According

to Schwandner et al.,14 the risk factors contributing

to the possibility of conversion during colorectal sur-

gery include male gender, extreme body status (body

mass index <20 kg/m2 or Q 27.5 kg/m2), and diver-

ticular disease. Schlachta et al.15 found patient’s

weight, the presence of malignancy, and surgeon’s

experience to increase the risk for conversion. In the

case of Crohn’s disease, the factors associated with an

increased likelihood for conversion include internal

fistula, smoking, steroid administration, extracecal

colonic disease, and preoperative malnutrition.16

In a multicenter study of 1,658 patients undergoing

LCR, Marusch et al.17 reported higher intraoperative

and postoperative complication rates, longer opera-

tive time, and prolonged hospitalization after con-

version compared with procedures completed

laparoscopically. In a review of patients undergoing

laparoscopic sigmoidectomy for diverticular disease,

Le Moine et al.18 described similar results, with

longer operating time, leaving a drain, return to

intestinal transit, time in the intensive care unit, and

hospital stay in converted than in nonconverted

cases. They also reported higher postoperative

morbidity rates in converted than in nonconverted

cases. However, because the conversions include

operations with increased risk for complications or

the complication has previously occurred, there is an

evident bias compared with those completed lapa-

roscopically. In our opinion, the converted group

should be compared with the open group, because

an important issue is to decide whether converting

an operation results in poorer outcomes than if the

operation was performed completely with an open

technique, especially in a procedure with relatively

high conversion rates, such as LCR. Slim et al.19

reported prolonged operating times, lengthened

postoperative ileus, delayed hospital stay, and higher

postoperative morbidity rate, including higher inci-

dence of anastomotic leaks in patients requiring

conversion during a laparoscopic-assisted colorectal

resection compared with patients who underwent an

open procedure.

As expected, our results show that converting a

laparoscopic procedure results in higher EBL and

prolonged time to first bowel movement and LOS

than in nonconverted cases. Bleeding was the indica-

tion for conversion in some of our patients, which

added to the blood loss derived from the operation

once it was converted to open. This may have been

the reason why the EBL was higher in this group.

However, the need for transfusion in these patients

was significantly lower than in the OCR group.

The fact that the operating time in the CCR group

was similar to LCR reflects the surgeons’ experience in

recognizing early the cases that would require con-

version. This also is important because it has been

documented that patients in whom the need for

conversion is made early have better surgical out-

comes, particularly lower complication rates. Because

this is a retrospective review, it was impossible to

assess how long after the operation was started until it

was converted to open. However, we were able to

compare patients in whom the indication for conver-

sion was a complication with those in whom the

surgery was converted without complications. Al-

though patients in the former group required trans-

fusions more frequently and had higher postoperative

complication and mortality rates than patients in the

latter group, the difference did not reach statistical

significance.

Interestingly, the time to first bowel movement and

LOS was longer in the CCR group than in the

laparoscopic group but also was significantly shorter

than in the OCR group. Many times the incision

required for the conversion is not as large as the one

required for a formal laparotomy resulting in less

postoperative pain. This may allow for faster patient

ambulation, which helps accelerate intestinal motili-

ty. Also, whenever the procedure is converted after

part of the dissection is performed laparoscopically,

there is no need for a large amount of manipulation

and mobilization of the abdominal contents for

exposure. It has been shown in animal studies that

the laparoscopic-assisted resections lead to a short-

ened postoperative ileus compared with open sur-

gery, which is evidenced by a significantly earlier

restoration of intestinal motility indicated by the

electric activity front of the migrating motility com-

plex20 and lower levels of gut cytokines.21 Conse-

quently, less pain and faster bowel recovery may

account for faster discharge of the patient from the

hospital.

Experience plays a significant role in the conver-

sion rate in any laparoscopic procedure. It is known

that conversion rates decrease as surgeons gain

experience in performing a certain procedure. Fur-

thermore, the learning curve is associated with

increased morbidity.8,10 This is important when

evaluating outcomes of a procedure with a long

202 GONZALEZ ET AL Dis Colon Rectum, February 2006

learning curve that includes multiple different tech-

niques and underlying diseases.17 We have included

our initial experience in our series finding a decrease

in conversion rates from 38 percent in the first 50

procedures to 12 percent in our last 50 procedures.

This clearly indicates a learning phase that was

overcome through time and experience.

We recognize the limitations of a retrospective

study, especially in terms of a surgeon’s choice of

approaching a patient with either technique. Al-

though the patients were matched for demographics,

indication for the colorectal resection, and type of

procedure performed, some of the cases perceived as

more difficult were probably approached with the

open technique. Although this subject would ideally

be addressed in a prospective study, randomization

of patients requiring conversion is not possible for

obvious reasons.

CONCLUSIONS

Conversion of LCR results in poorer outcomes than

the LCR because patients have higher EBL, delayed

time to first bowel movement, and prolonged LOS.

However, most importantly, the converted cases

have similar outcomes to OCR. In fact, patients in

the converted group required fewer blood trans-

fusions, had shorter time to first bowel movement,

and shorter hospital stay than patients in the open

group. Even when patients in whom the indication

for conversion was a complication were evaluated,

there was no difference in postoperative morbidity or

mortality compared with those in whom the proce-

dure was converted to avoid complications. Experi-

ence and good judgment are fundamental for timely

conversion of a laparoscopic procedure to open to

decrease complication rates. Despite a high conver-

sion rate, surgeons should consider LCR, because

when conversion is necessary it does not result in

poorer outcomes than LCR or OCR. Ideally, LCR

should be performed by surgeons experienced in

colorectal diseases and adequately trained in mini-

mally invasive techniques.

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