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Perioperative Outcomes of Robotically Assisted Hysterectomy for Benign Cases With Complex Pathology

Boggess, John F. MD; Gehrig, Paola A. MD; Cantrell, Leigh MD; Shafer, Aaron MD; Mendivil, Alberto MD; Rossi, Emma MD; Hanna, Rabbie MD

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doi: 10.1097/AOG.0b013e3181b47030
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Minimally invasive surgical techniques for performing hysterectomy have been shown to reduce patient morbidity and shorten hospital stay.1,2 Although there have been reports of the successful use of laparoscopic techniques for obese patients3 and patients with large uteri,4–7 surgeons are often limited in the complexity of the procedures that they can perform using conventional laparoscopy.

A robotic system (da Vinci Surgical System, Intuitive Surgical, Inc., Sunnyvale, CA) is designed to address many of the limitations of conventional laparoscopy, and these benefits may allow for a minimally invasive approach in more complex cases, demonstrating the feasibility and safety of this technology as effective without increasing morbidity. However, although there have been several pilot studies on alternatives to laparoscopic hysterectomy for both benign and oncologic indications,8–14 to date there have only been two larger-scale studies of robotic-assisted total hysterectomy specifically for benign indications.15,16 In addition, the advantages of robotics may become even more apparent in complex cases, where the use of conventional laparoscopy is traditionally contraindicated. For example, one study reported success in treating six patients for pelvic adhesive disease with robotic-assisted total hysterectomy with good patient outcomes.17

As a gynecologic oncology practice at a teaching institution,18,19 the benign cases that we see are often complex cases. In this study we sought to investigate whether robotic assistance facilitates the surgery and results in low morbidity and acceptable perioperative outcomes.

MATERIALS AND METHODS

Implementation of a robotics program took place at our institution in May 2005. One hundred fifty-two patients underwent robotic hysterectomy for noncancer indications from May 2005 to May 2008. A systematic chart review of consecutive robotic cases was conducted based on preoperative and perioperative characteristics of each patient. Each case was evaluated for its complexity based on preoperative diagnosis, prior pelvic or abdominal surgery, patient’s body mass index (BMI), and uterine weight. Prior pelvic or abdominal surgery was categorized as a dichotomous variable (ie, presence or absence), as was surgical indication of leiomyomas or endometriosis (ie, presence or absence of leiomyoma or endometriosis). Body mass index was categorized based on patients with BMI less than 30 or those with BMI of 30 or greater. Uterine weight was categorized using a threshold value of 250 g. All cases were further categorized as being teaching cases or nonteaching cases. Before the commencement of this study, institutional review board approval was obtained from the University of North Carolina at Chapel Hill for data collection on patients who consented. One experienced surgeon performed the majority of cases with resident and or fellow assistance for 44.7% of cases. In those cases, an attending or resident performed parts of the robotic procedure at the console with supervision. The level of resident involvement was based on the complexity of the case, with the experienced surgeon performing the more complex cases. Data analyses were conducted using SAS 9.1.3 software (SAS Institute, Inc, Cary, NC). Frequencies or means with standard deviation and 95% confidence intervals were reported. Regression modeling based on the previously mentioned independent variables and their categorizations was carried out to determine what factors influenced operative time. Results of this study were contrasted to similar studies in the published literature.

Patients included in this study had hysterectomy for benign gynecologic conditions. All cases were performed under general endotracheal anesthesia. Antibiotics were given just before surgery. Patients were placed in dorsal lithotomy position with Allen stirrups (Allen Medical Systems, Acton, MA) for lower extremity positioning. A Zumi System uterine manipulator with balloon tip (Cooper Surgical, Trumbull, CT), KOH Colpotomizer System and vaginal pneumooccluder balloon (Cooper Surgical) were placed after appropriate preparation and draping. Patients were placed in a steep Trendelenburg position, with arms tucked at the sides and shoulder blocks placed to limit shift on the operating room table. All cases were started using a 2-mm laparoscopic port placed in the left-upper quadrant of the abdomen, midclavicular line and 2 cm below the costal margin. This approach allows for insufflation of CO2 and allows for the survey of the abdomen with a 2-mm laparoscope to assess pathology and the presence of abdominal adhesions. This technique is particularly helpful in patients with prior abdominal surgery, where placement of a trocar within the prior surgical field would be hazardous. In addition, it allows placement of all larger trocars under direct visualization after the abdomen has been insufflated. It is important to place an oral–gastric tube at the beginning of the case to prevent trauma to the stomach. Three to four bladeless trocars were placed in the patient’s abdomen, two 8-mm robotic trocars, and one extra-long 12-mm trocar for the camera. An additional 8-mm robotic trocar was placed on selected cases where additional retraction was necessary. Finally, the original 2-mm port was replaced with a 5-mm port to allow the bedside surgical assistant to use a grasper or suction-irrigation device. The robotic system was then docked between the legs. All cases were performed using monopolar EndoWrist scissors (Intuitive Surgical, Inc.) combined with the bipolar fenestrated grasper. Hysterectomies were performed according to the American Association of Gynecologic Laparoscopists type IVE hysterectomy using the KOH Colpotomizer System (Cooper Surgical). The American Association of Gynecologic Laparoscopists type IVE hysterectomy is defined as total laparoscopic removal of the uterus and cervix including vaginal cuff closure.

All pathologic specimens were removed using one of the four following methods: direct removal through the vaginal cuff opening, morcellation of the specimen using an endoscopic morcellator, sectioning of the uterine specimen with robot using an EndoWrist monopolar cautery instrument (Intuitive Surgical, Inc.) to portions small enough to be delivered vaginally, or by minilaparotomy with manual morcellation for three cases where the uterus was more than 2,000 g. The vaginal cuff was closed robotically using 0 polyglactin (Vicryl, Ethicon Endo-Surgery, Inc., Cincinnati, OH) on a CT-1 needle in a running suture closure. Tension was maintained throughout the cuff closure by the assistant using a needle driver to hold the suture tight as the subsequent stitch was placed. Sutures were instrument-tied using the robotic instruments. Patients were desufflated, and pedicles were checked at half desufflation for hemostasis. The robotic system was then undocked, and all trocars were removed under direct visualization. The 12-mm trocar sites received a single deep 0-polyglactin suture, and all skin incisions were closed with 4–0 polyglactin subcuticular sutures. Adhesive skin closures (Steri-Strips, 3M, St. Paul, MN) were placed as dressing.

The following times were recorded: docking time, defined as the time from first incision to placement of the robotic instruments into the patient; morcellation time; and total operative time, defined as first skin incision to wound closure. In addition, uterine weight, blood loss, transfusion rate, conversions, intraoperative and postoperative complications requiring intervention, as well as length of hospital stay were monitored and recorded. Cases were stratified based on the level of complexity using BMI, uterine weight, presence of prior pelvic or abdominal surgeries, and preoperative diagnosis. We also report outcomes for subgroups of patients with uterine weight of 500 g or more, or BMI of 30 or more.

RESULTS

A total of 152 consecutive patients underwent hysterectomy with robotic assistance for benign indications between May 2005 and May 2008. Patient characteristics and surgical indications are listed in Table 1. The patients were on average aged 46.9±9.4 years (range 23.0–88.0 years) with a BMI of 30.7±8.7 (range 17.0–63.3). There were 48% of patients who were considered obese based on having a BMI equal to or exceeding 30 and 16.4% who were morbidly obese based upon a BMI greater than 40. Endometriosis or leiomyomas or both were the main indication for 34.2% of patients. The racial composition of patients included 79% white, 17.1% African-American, 2.6% Hispanic, and 1.3% Asian women. More than 62% of all patients had undergone prior abdominal or pelvic surgery. Of these women 15.1% had undergone multiple prior abdominal or pelvic surgeries. Patients underwent total hysterectomy with (97.3%) or without (2.6%) unilateral or bilateral salpingo-oophorectomy, with 2.6% of patients undergoing additional procedures. The average uterine weight was 347.0±389.2 g (44.0–2140.0 g) with more than 40% of patients having a uterine weight greater than 250 g and 19.1% of patients with a uterine weight of 500 g or more. One patient received a preoperative transfusion for iron-deficient anemia. Total operative time was on average 122.9 minutes, which included morcellation time when applicable (Table 2).

Table 1
Table 1:
Preoperative Characteristics
Table 2
Table 2:
Operative Characteristics

There were 44.7% of cases in which an attending, fellow in training, or resident performed parts of the robotic procedure at the console with supervision. Although the operative time was longer for these teaching cases (125.5 minutes compared with 119.5, P=.4). Patients in this study experienced an average blood loss of 79.0 mL (10.0–1,200.0 mL) with no one requiring a transfusion as a result of the procedure. There were three patients with a blood loss more than 500 mL; in all three cases, uterine weight was in excess of 1,000 g. There were three (2.1%) intraoperative complications that were successfully handled robotically without the need for conversion. These included a vaginal laceration, a ureteral injury, and one bowel injury. There were five (3.5%) patients with seven postoperative complications (occurring within 30 days), which included a patient with transient femoral nerve palsy and urinary tract infection, one patient with a vaginal cuff abscess and pain with intercourse, one vaginal hematoma, and two patients with urinary tract infection, one of which was a result of a preexisting condition. Patients had an average length of stay of 1.05±0.69 days (range 0–3.0 days).

The majority of cases in this cohort underwent hysterectomy for complex pathology. As such, a multiple regression model was used to determine whether predetermined factors affecting complexity influenced operative time. Preoperative diagnosis, evidence of prior multiple pelvic or abdominal surgeries, and BMI did not affect operative time. The only variables that were significantly associated with increased operative time were a large uterus (more than 250 g) and fellow or resident involvement (Table 3). This was true when each variable was taken into account separately as well as collectively.

Table 3
Table 3:
Regression Model: The Effects of Preoperative Characteristics on Operative Time

For the purpose of observational comparison to articles in the literature reporting on patient populations with complex pathology, specifically a uterine weight 500 g or more or BMI 30 or more, similar subgroups are presented below. In the subgroup of patients with uterine weight 500 g or more, overall operating time was 155.8±67.6 minutes (range 68.0–325.0 minutes), with an average morcellation time of 41.6 minutes. Blood loss in this subgroup was 135.3±236.8 mL (range 25.0–1200.0 mL), with one (1.3%) intraoperative vaginal laceration and one (1.3%) postoperative vaginal hematoma. Average hospital stay for this subgroup was 1.0±0.3 days (range 1.0–2.0 days). In the subgroup of patients (BMI 30 or more), overall operating time was 130.8±48.8 minutes (range 60.0–325.0 minutes). Blood loss in this subgroup was 103.3±182.0 mL (range 10.0–1200.0 mL), with two (2.6%) intraoperative complications, including one ureteral injury and one vaginal laceration previously reported in the subgroup above (500 g or more uterine weight). There were two (2.6%) postoperative urinary tract infections. Average hospital stay for this subgroup was 1.0±0.3 days (range 1.0–3.0 days).

DISCUSSION

This study presents our experience with robotic-assisted total hysterectomies for benign indications in 152 consecutive cases. All were successfully completed robotically without the need for conversion. We report on patients with complex pathology and demonstrate a lack of perioperative blood transfusions, a short hospital stay, low blood loss, low morbidity rates, and short operative times. In addition, the only factors that extended operative times were resident or fellow involvement or a large uterus. The latter can be explained by increased morcellation time, rather than an increased difficulty of the surgery.

With the development of minimally invasive techniques, outcomes after total hysterectomies have improved over those seen after abdominal hysterectomy.20 However, in a study by Leonard et al21 the authors showed that BMI, uterine size, leiomyoma size, and a history of adhesion-causing abdominopelvic surgery are all independent risk factors for intraoperative conversions from laparoscopy to laparotomy. In addition, Bonilla et al1 demonstrated that a large uterus increased the risk of a longer hospital stay, increased morbidity, and increased blood loss. Thus, these characteristics provide a measure of the complexity and potential difficulty of a surgery.

With extensive experience performing robotic radical hysterectomies to treat cervical cancer19 and robotic total hysterectomies with lymph node dissection and bilateral salpingo-oophorectomy to treat endometrial cancer,18 the primary surgeon was able to perform robotic total hysterectomies on obese patients, patients with one or more prior pelvic or abdominal surgeries, patients with moderate to severe endometriosis or leiomyomas, and patients with large uteri without conversion to laparotomy and with excellent patient results. In addition, the only factor influencing operative time, was a uterine size more than 250 g, which was due to an increase in morcellation time, rather than an increase in the difficulty of surgery.

Although the literature on the use of robotic surgery for hysterectomies for benign conditions is sparse, as seen in Table 4, there are a few recent studies reporting on large patient populations.15,16 However, our average BMI and uterine weight are higher than other published studies8,10,13,15–17 (Table 4). The incidence of prior abdominal surgery is similar for those studies that have included this measure, whereas the operative time for this study is at the lower end of the range reported (122.9 minutes compared with 119.4–254 minutes). The estimated blood loss for this study at 79.0 mL is within the range of averages reported for all benign robotic hysterectomy studies to date, most of which report on noncomplex cases (61–102.5 mL). The length of stay for all of the robotic studies reported is within 1.5 days, with the majority of patients discharged in 1 day. One striking difference in the robotic reports as compared with both the laparoscopic and laparotomy reports (seen in Table 4 and 5, respectively) is the complete lack of blood transfusions. In addition, even with many highly complex surgeries, there were no conversions in our study. Complication rates for our study are comparable to the two other reports on a large patient population.15,16

Table 4
Table 4:
Summary of Reports on Robotic Hysterectomy for Benign Indications
Table 5
Table 5:
Summary of Reports on Laparoscopic Hysterectomy for Benign Indications

We also contrasted our results to those of other studies reporting on the outcomes after complex laparoscopic total hysterectomies. Our criteria for categorizing hysterectomy as complex were high BMI, large uterine weight, prior major pelvic or abdominal surgery, and surgical indications, including endometriosis and leiomyomas1,4–7,21–26 (Table 5). When compared with these studies with similar patient characteristics, we report equivalent operative times at 122.9 minutes compared with the reported range in the literature of 80–159.8 minutes, lower blood loss of 79.0 mL compared with a range of 80–311.6 mL, a shorter length of stay of 1.0 day compared with a range of 1.3–3.6 days, and lower complication and conversion rates.

For the purposes of observational comparison of our results to those published in the literature, we report on the outcomes for patients with uterine weight 500 g or more or high BMI. When we specifically compare our results for the subgroup of patients with uterine weight 500 g or more, we report an increase in operative time of 30 minutes, due to increased morcellation time, an increase in blood loss of approximately 50 mL, and no increases in length of stay. When comparing this subgroup with a conventional laparoscopic study where all patients also had uterine weights more than 500 g, we see equivalent operative times, a shorter length of stay, and fewer intraoperative and postoperative complications.7

Upon examining our results for the subgroup of patients with a BMI greater than or equal to 30, we see very small increases in operative time (approximately 10 minutes) and in blood loss (approximately 20 mL) with no increase in length of stay. When we again compare our results with conventional laparoscopic hysterectomy in obese patients, we report a shorter operative time by approximately 30 minutes, lower blood loss by approximately 60 mL and shorter hospital stay.3

We also contrast our results to those reported after total hysterectomy by laparotomy5,22,23,25,27–36 (Table 6). Similar criteria were used for choosing these comparative studies. The literature result for total abdominal hysterectomy reports similar operating times, greater blood loss, and longer hospital stays. One of the concerns with conventional laparoscopy has been an increased rate of intraoperative complications. Our intraoperative complication rate at 2.1% was within the range reported in the abdominal hysterectomy studies (0.5–2.3%), with one study reporting an intraoperative complication rate of 8.5%. We report a postoperative complication rate of 3.5% compared with a low of 3.9% and a range of 11.5–40.7% for abdominal hysterectomy studies.

Table 6
Table 6:
Summary of Reports on Laparotomy Hysterectomy for Benign Indications (All Comparative Studies)

Limitations of this study include the fact that we do not report data for concurrent laparoscopic or abdominal cohorts for comparison, that the generalizability of the results may be limited due to the level of experience of the primary surgeon, and that residents assisted mainly on the less complex cases.

This study represents a large cohort of patients treated with robotic-assisted total hysterectomies for complex benign indications. Even in patients with several high-risk factors, we demonstrate a short hospital stay and minimal blood loss, with no conversions. This suggests that the increased precision and dexterity afforded by the use of robotic assistance allows for a safe and efficient surgery even for patients with complex pathology. Ideally, these results should be confirmed by future comparative studies.

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This article has been cited 1 time(s).

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© 2009 by The American College of Obstetricians and Gynecologists. Published by Wolters Kluwer Health, Inc. All rights reserved.