NEW ORLEANSIn patients undergoing laparoscopic procedures for gynecologic lesions, complications and conversion to laparotomy can be predicted based on several risk factors, according to the 10-year experience of Memorial Sloan-Kettering Cancer Center investigators, presented at the 34th Annual Meeting of the Society of Gynecologic Oncologists (SGO abstract 74).
Dennis S. Chi, MD, reported the findings from a retrospective chart review of all 1,452 patients undergoing laparo-scopic procedures by the gynecologic oncology service at Sloan-Kettering between 1991 and 2000. Currently, more than 50% of abdominal and/or pelvic procedures on this service are performed using a laparoscopic approach, Dr. Chi said.
The study evaluated the procedures according to the level of surgical complexity and the seriousness of the complications that were observed.
The four levels of surgical complexity, based on the degree of difficulty of the planned procedure, were: I diagnostic; II operative procedures on the uterus and/or adnexa; III second-look procedures for malignancy; and IV lymphadenectomies and/or other radical operative procedures, such as radical hysterectomy or splenectomy.
Complications occurring intraoperatively or within 30 days of surgery were assessed by an institutional grading system from 1 (mild) to 5 (death). Grade 3 complications required introperative radiology or operative intervention for correction; grade 4 resulted in chronic deficit, disability, or organ resection. Procedures converted to laparotomy as part of the planned management of malignant disease were not included as complications or conversions for technical difficulty.
In the 1,448 evaluable laparoscopic procedures, older age, previous abdominal and/or pelvic radiation therapy, and malignant histology were found to be significant risk factors for laparoscopic complications, while prior abdominal surgery significantly increased the risk of conversion to laparotomy.
Overall, grade 1-5 complications occurred in 7% of patients, with major (grades 3-5) complications seen in 2% of the entire group. There were only three grade 5 complications, and these all occurred in patients with malignancies who underwent diagnostic laparoscopies; one patient died of a postoperative pulmonary embolus, one due to cardiac arrhythmia, and one due to a bowel injury at the time of initial laparoscopic peritoneal access. This procedure was converted to a laparotomy for bowel repair, after which the patient developed uncontrollable sepsis leading to her death, he said.
On univariate analysis, the significant risk factors and relative risk (RR) for major complications (grade 3-5) were older age (RR 1.42), previous abdominal surgery (3.04), prior radiotherapy (4.88), and malignant histology (3.64). Higher body mass index, prior chemotherapy, and higher surgical level were not significant risk factors.
On multivariate analysis, previous abdominal surgery did not retain statistical significance, but older age, prior radiotherapy, and malignant histology did.
"Focusing specifically on the issue of malignant histology, we saw that while this did increase the rate of major complications, the actual rate for complications in this subgroup was only 4%," he added.
Conversions for Technical Reasons
Technical difficulty and/or complications led to conversion to laparotomy in 104 cases, or 7% of the cohort. The conversion rate actually decreased according to the level of surgical complexity, falling from 10% for diagnostic procedures (level I), to 8% for level II, 4% for level III, and only 1% for level IV, the most radical procedures, Dr. Chi reported. "This lower rate of conversion for higher level procedures is perhaps due to patient selection and/or increased laparoscopic expertise of the surgeons attempting more complex procedures," he said.
On univariate analysis, prior abdominal surgery was a significant risk factor for conversion to laparotomy (RR 2.94) while higher surgical level was associated with decreased risk of conversion due to technical difficulty (RR 0.11). On multivariate analysis, both previous abdominal surgery and surgical difficulty retained significance.
"Both simple and complex laparosco-pic procedures can be performed on a gynecologic oncology service with a low rate of complications and an acceptable rate of conversion to laparotomy. Risk factors should be taken into account in preoperative patient counseling and surgical planning," Dr. Chi concluded.
The discussant for the paper, Robert S. Mannel, MD, professor of obstetrics and gynecology, University of Oklahoma College of Medicine, noted that this series is one of the largest reported in the literature for gynecologic laparoscopic procedures and therefore adds useful and reliable information. Dr. Mannel noted, however, that the wide range of procedures and indications "makes the data hard to analyze."
For complications, he said, "the major risk factors found in this study are also those typically found with open techniques, so the real question is whether the laparoscopic approach led to an increased or decreased risk of complications as opposed to an open technique." This is hard to determine without a control group, he noted.
With regard to conversions to laparotomy, obesity is universally recognized as a risk factor, but this does not emerge in this study, he pointed out.
Regarding the low rates of complications and conversions, Dr. Mannel said, "the possibilities are that the study is underpowered, which does not appear to be the case; the surgeons are ‘awesome’ and they do not have these problems; or selection bias may be a problem." ONI