Hysterectomy is one of the most common surgical procedures performed annually in the United States, and the rate of inpatient hysterectomy has declined recently to approximately 400,000.1–4 The procedure has recently garnered attention regarding the use of laparoscopic and robotic techniques and power morcellation.5,6 Owing to diverse indications for hysterectomy, there are significant differences in resource utilization and complications. Knowledge of these outcomes is necessary for counseling, benchmarking, and cost analysis.
Hysterectomy is commonly performed for benign indications such as leiomyomas or gynecologic malignancy.7,8 Trends in hysterectomy reflect an emphasis on minimally invasive surgery with anticipated shifts away from inpatient abdominal hysterectomy.2,9,10
Considering these profound practice changes and diverse indications for hysterectomy, specific data regarding outcomes would be valuable. Although differences in complication rate and outcomes are expected when comparing benign and malignant hysterectomy, no large database studies have specifically defined this difference. Additionally, it is imperative for hospitals to compare system-based trends in morbidity and mortality to improve care. The National Surgical Quality Improvement Program database was established by the American College of Surgeons.11,12 This program prospectively collects data to allow risk adjustment and 30-day follow-up from more than 500 participating hospitals. The National Surgical Quality Improvement Program allows evaluation on a national basis to identify opportunities to identify risk factors and improve outcomes. We sought to better understand the complexities of hysterectomy by defining and comparing national complication rates after hysterectomy for benign with malignant indications.
MATERIALS AND METHODS
The National Surgical Quality Improvement Program database was used to retrospectively identify patients who underwent hysterectomy from January 2008 to December 2012. Current Procedural Terminology (CPT) codes were used to separate hysterectomy from other surgical procedures. International Classification of Diseases, 9th Revision codes were used to determine the indication for hysterectomy and to differentiate between benign (218, 291, 617, 618, 621, 625–627) and malignant (180–184, 158.0, 158.8, 158.9, 179, 197.6, 198.6, 198.82, 199.0, 199.1, 236.0, 236.2, 236.3) procedures. Using CPT codes, hysterectomy procedures were further divided into laparotomy (58150, 58152, 58200, 58210, 58951, 58953, 58954, 58956, 58180) and minimally invasive surgery (58260, 58262, 58263, 58367, 58270, 58275, 58280, 58285, 58548, 58550, 58552, 58553, 58554, 58570, 58571, 58572, 58573, 58290, 58291, 58292, 58293, 58294, 58541, 58542, 58543, 58544). Patients were excluded if the procedure was not performed for gynecologic indications or if sex was not specified as female. Patients undergoing pelvic exenteration for gynecologic malignancy were also excluded, because the extent and complexity of the surgery would not be easily comparable with other types of hysterectomies. The primary endpoint was to determine complication rates of benign compared with malignant hysterectomy. The secondary endpoint included determining risk factors for complications.
The National Surgical Quality Improvement Program prospectively collects data, including patient risk factors, to allow accurate risk adjustment and 30-day postoperative follow-up from more than 500 participating hospitals nationally. The results are reported to each institution as observed-to-expected performance in comparison with other hospitals.11 Complications and patient variables were defined and abstracted according to National Surgical Quality Improvement Program methodology.11
Patient demographics and preoperative, intraoperative, and postoperative characteristics were summarized by standard summary statistics such as the mean (standard deviation) for continuous variables and frequencies (%) for categorical variables. Complication rates were computed at the patient level such that multiple complications reported for a patient were treated as a single event. Rates stratified by benign compared with malignant diagnoses or hysterectomy type were computed by complication type and compared by χ2 testing. Exact tests and Monte Carlo estimates for the exact test were used to compute P values when event rates were observed to be low. Operating times were summarized by percentiles and compared between diagnosis and procedure groups through Kruskal-Wallis tests. Logistic regression models were estimated to examine the association among patient, intra- and postoperative characteristics, and the probability of any complication. Unplanned readmission and return to the operating room were only available for 2011–2012 and therefore were not included as events for the regression models. Odds ratios (ORs) based on univariate and multivariable models (adjusted for indication, primary procedure performed, age, race, body mass index (BMI, calculated as weight (kg)/[height (m)]2), American Society of Anesthesiologists class, concurrent procedures, preoperative transfusion, and preoperative hematocrit levels) were presented for each factor of interest along with 95% confidence intervals. Two-sided P values were generated by χ2 tests and values <.05 were considered statistically significant. All analyses were performed using SAS/STAT 12.1. Institutional review board exemption was obtained from Winthrop University Hospital to perform this study, because the existing deidentified data in the National Surgical Quality Improvement Program database are publicly available.
Data from the National Surgical Quality Improvement Program database were collected from 211 hospitals in 2008, 237 in 2009, 258 in 2010, 315 in 2011, and 374 hospitals in 2012. During this time period, the National Surgical Quality Improvement Program collected data on 1,957,023 cases of which 66,876 (3.4%) were coded as hysterectomies. One hundred fifty-eight cases were excluded as a result of ineligible CPT codes, 7,031 were excluded as a result of ineligible International Classification of Diseases, 9th Revision codes, and 162 were excluded for missing sex or having sex listed as male. Therefore, a total of 59,525 hysterectomies met inclusion criteria for final analysis with 49,331 (87.2%) performed for benign and 10,194 (17.1%) for malignant indications (Fig. 1).
Patients who had hysterectomies for malignant indications were more likely to be older (mean age 60.8 compared with 47.5 years for benign indications), white non-Hispanic race (72.5% compared with 61%), and obese (52.3% BMI 30 or greater compared with 42.3%, respectively). These patients were also more likely to have hypertension (49.7% compared with 25.9%), diabetes (16.8% compared with 6.6%), American Society of Anesthesiologists class 3 or greater (48.1% compared with 16.4%), and longer hospital stays (33.4% compared with 5.3% greater than 4 days) (Table 1). These findings are not novel and confirm the higher acuity of the patient population undergoing surgery for malignancy.
Minimally invasive surgery was used for the majority of hysterectomies (66.2%); however, the rate was higher in benign cases (70.5%). This coincides with the known trend regarding minimally invasive hysterectomy approaches and the declining rate of inpatient hysterectomy.2 In contrast, an open approach was used more often for malignant hysterectomies (54.7%).
Complications, as defined by National Surgical Quality Improvement Program, were evaluated separately for benign and malignant hysterectomy.11 Data on wound complications, venous thromboembolism, urinary tract infections, sepsis, need for blood transfusion, death, unplanned readmission, and return to the operating room were collected and compared. The most common complication for benign hysterectomies was urinary tract infection. The most common complication in malignant cases was the need for intraoperative or postoperative blood transfusion within 72 hours of the procedure. The overall rate of complications for benign hysterectomy was 7.9% compared with a rate of 19.4% for malignant hysterectomy (Table 2).
Laparotomy performed for any indication was associated with greater rates of complications. In the benign group, total abdominal hysterectomy had the greatest rate of any complication (12.1%) and laparoscopic supracervical hysterectomy had the lowest rate (4.8%) (Table 3). In the malignant group, abdominal supracervical hysterectomy had the highest rate (34.8%) and total laparoscopic hysterectomy had the lowest (7.2%) (Table 4).
For benign cases, median operating room time, which reflects surgical start to end (incision to closure), but does not account for patient positioning and draping, was longer for laparoscopic cases (127.0 minutes) when compared with open cases (105.0 minutes; P<.001). Vaginal hysterectomy had the shortest operating time at 94.0 minutes. For malignant cases with a diagnosis of uterine or cervical malignancy, laparoscopy also had longer median operating room times (172.0 and 209.5 minutes, respectively; P<.001) compared with laparotomy (143.0 and 177.0 minutes, respectively). For ovarian cancer cases, laparoscopy and open cases had similar operating times (174.5 and 173.0 minutes, respectively; P=.09) (Table 4). The median operating time in malignant cases was significantly longer than for benign cases (P<.001).
Univariate and multivariable analyses were performed. Multivariable analysis identified that smoking (OR 1.12 [1.04–1.22]), partially dependent functional status (OR 1.51 [1.15–1.98]), all races except white or Caucasian (black or African American OR 1.10 [1.01–1.2], Asian OR 1.37 [1.17–1.60], other OR 1.28 [1.01–1.63], unknown OR 1.20 [1.09–1.33]), American Society of Anesthesiologists class 3–5 (OR 1.55 [1.45–1.66]), and being underweight (OR 1.37 [1.05–1.80]) remained significantly independently associated with risk of complication. Hysterectomies performed for malignancy and having disseminated cancer also significantly increased the risk of complication (OR 2.07 [1.92–2.22] and OR 2.38 [2.03–2.80], respectively). These findings are representative of a patient population with increased medical complexity, leading to increased postoperative complication rates. Perioperative factors such as concurrent procedures (OR 1.28 [1.21–1.36]), operating room time greater than 2–3 hours (OR 1.44 [1.27–1.64], 3–4 hours OR 2.11 [1.84–2.41], 4–5 hours OR 2.89 [2.48–3.37], greater than 5 hours OR 4.20 [3.57–4.95]), preoperative blood transfusion (OR 2.46 [1.97–3.06]), and uterine weight greater than 250 g (OR 1.15 [1.02–1.30]) increased the risk of complication, showing that prolonged operating time, often as a result of increased surgical complexity, leads to more complications. Hispanic ethnicity, any race (OR 0.87 [0.79–0.96]), higher preoperative albumin (OR 0.64 [0.58–0.70]), higher preoperative hematocrit (OR 0.92 [0.92–0.93]), and all procedures other than total abdominal hysterectomy (supracervical hysterectomy OR 0.36 [0.32–0.41], vaginal hysterectomy OR 0.82 [0.72–0.94], total laparoscopic hysterectomy OR 0.40 [0.37–0.43], laparoscopic supracervical hysterectomy OR 0.54 [0.49–0.59]) were related to decreased complication rates (Tables 5 and 6).
This study reveals the complication rate after hysterectomy is more than twofold higher when performed for malignant compared with benign conditions. Additionally, median operating time was significantly longer for laparoscopic cases and malignant cases. These findings suggest an association relating increased complexity of patients with malignancy and additional skill required for laparoscopic procedures. Prior studies show the benefit of minimally invasive surgery in decreasing complication rates, realizing the increased cost associated with some techniques such as robotic surgery.13–15 Little has been written directly comparing benign and malignant hysterectomy using a nationwide database.
The 2011–2012 National Health and Nutrition Examination Survey showed that 65.8% of women older than age 20 years are overweight or obese.16 However, 73.1% and 75.9% of women undergoing benign or malignant hysterectomy, respectively, are overweight or obese (Table 1). The overrepresentation of obese women in this cohort likely represents obesity-driven estrogen-dependent pathology, including leiomyomas, abnormal uterine bleeding, and endometrial cancer.17–19 Infection risk increases with elevated BMI, and a higher rate of overall complications has been reported in ovarian cancer debulking surgery.20,21
Surgical approach to hysterectomy is an important consideration during preoperative assessment and surgical planning. Consistent with prior studies, the National Surgical Quality Improvement Program data demonstrate that minimally invasive surgery is associated with lower rates of wound complications, venous thromboembolism, and urinary tract infection.15,22 Open procedures were associated with a higher risk of complications in both benign and malignant cases (Tables 3 and 4). Laparoscopy is known to require longer surgical times,22,23 which is confirmed by our data. The tradeoff for longer times, and potentially higher intraoperative costs, is justified by lower complication rates. Given that laparotomy is commonly performed for malignant conditions, the increased rate of complications for the open approach is anticipated. However, the rate of minimally invasive surgery in malignant patients in this study was substantial (45.3%).
Preoperative variables play a role in surgical planning and outcomes.20,21,24,25 This study shows Asian women were more likely to experience complications, which is consistent with previous research. This could be partially explained by prior studies showing Asian women may be more likely to have endometriosis and less likely to undergo laparoscopic hysterectomy.26–28 Although many risk factors are not alterable such as race, suppression of abnormal bleeding and correction of anemia are feasible in most benign cases.
Guidelines for hysterectomy approach exist, understanding that this decision is complex.1,3 Recently, the U.S. Food and Drug Administration issued an updated recommendation against the use of power morcellation for hysterectomy for uterine leiomyomata.29 Harris et al6 showed a decline in laparoscopic hysterectomy rate of 4.1% and a significant increase in postoperative blood transfusion and readmission following the U.S. Food and Drug Administration warning. These findings emphasize the need for continued discussion regarding hysterectomy method to ensure sustained patient safety.
Reimbursement of surgical procedures is a frequently discussed and debated topic. In 2012, the relative value unit, a measure of perioperative effort determining reimbursement, was 17.31 for total abdominal hysterectomy (CPT code 58150), 15.88 for total laparoscopic hysterectomy for a uterus less than 250 g (CPT code 58570), and 14.15 for vaginal hysterectomy for a uterus less than 250 g (CPT code 58260). As of 2015, relative value units were reduced for laparoscopic hysterectomies. Justification for these changes included reduced physician involvement during postsurgical care. However, the increased time and effort during surgery were not recognized nor was the overall lower complication rate rewarded. Consequently, surgeons will be reimbursed less for minimally invasive surgery despite longer operating room times24 (Table 7).
Strengths of this study include use of the National Surgical Quality Improvement Program database to obtain national, validated data. As a result of multiple data points, multivariate analysis was used to control for confounding factors. Weaknesses of retrospective studies apply. Additionally, the data are limited to the hospitals participating in the database. Although a random sample, this may not represent all practices. The database cannot account for factors that determine the selection of hysterectomy approach.11
This study provides rates of complications after hysterectomy based on prospectively collected, national data. This information is useful for surgical planning and counseling, equipping physicians and patients with current information regarding operating times and complication rates related to patient and perioperative characteristics. The data also serve as reference for public health decision-making such as the morcellation debate and projecting health care costs. Our comprehensive data give evidence regarding distinct variables suggesting increased complexity and complications, which provides objectivity to public health discussions. In addition, this study should be considered for determining models for value-based reimbursement, which includes patient complexity and effort involved in perioperative care.
1. Choosing the route of hysterectomy for benign disease. ACOG Committee Opinion No. 444. American College of Obstetricians and Gynecologists. Obstet Gynecol 2009;114:1156–8.
2. Wright JD, Herzog TJ, Tsui J, Ananth CV, Lewin SN, Lu YS, et al. Nationwide trends in the performance of inpatient hysterectomy in the United States. Obstet Gynecol 2013;122:233–41.
3. Mäkinen J, Johansson J, Tomás C, Tomás E, Heinonen PK, Laatikainen T, et al. Morbidity of 10 110 hysterectomies by type of approach. Hum Reprod 2001;16:1473–8.
4. Wu JM, Wechter ME, Geller EJ, Nguyen TV, Visco AG. Hysterectomy rates in the United States, 2003. Obstet Gynecol 2007;110:1091–5.
5. Adelman MR. The morcellation debate: the history and the science. Clin Obstet Gynecol 2015;58:710–7.
6. Harris JA, Swenson CW, Uppal S, Kamdar N, Mahnert N, As-Sanie S, et al. Practice patterns and postoperative complications before and after US Food and Drug Administration safety communication on power morcellation. Am J Obstet Gynecol 2016;214:98.e1–13.
7. Koh WJ, Greer BE, Abu-Rustum NR, Apte SM, Campos SM, Cho KR, et al. NCCN clinical practice guidelines in oncology, uterine neoplasms. Fort Washington (PA): National Comprehensive Cancer Network; 2015.
8. Morgan RJ, Armstrong DK, Alvarez RD, Bakkum-Gamez JN, Behbakht K, Chen L, et al. NCCN clinical practice guidelines in oncology, ovarian cancer including fallopian tube cancer and primary peritoneal cancer. Fort Washington (PA): National Comprehensive Cancer Network; 2015. Available at: https://www.nccn.org/professionals/physician_gls/pdf/ovarian.pdf
. Retrieved March 2, 2016.
9. Oliphant SS, Jones KA, Wang L, Bunker CH, Lowder JL. Trends over time with commonly performed obstetric and gynecologic inpatient procedures. Obstet Gynecol 2010;116:926–31.
10. Loring M, Morris SN, Isaacson KB. Minimally invasive specialists and rates of laparoscopic hysterectomy. JSLS 2015;19:e2014.00221.
12. Ingraham AM, Richards KE, Hall BL, Ko CY. Quality improvement in surgery: the American College of Surgeons National Surgical Quality Improvement Program approach. Adv Surg 2010;44:251–67.
13. Corrado G, Cutillo G, Pomati G, Mancini E, Sperduti I, Patrizi L, et al. Surgical and oncological outcome of robotic surgery compared to laparoscopic and abdominal surgery in the management of endometrial cancer. Eur J Surg Oncol 2015;41:1074–81.
14. Wright JD, Ananth CV, Lewin SN, Burke WM, Lu YS, Neugut AI, et al. Robotically assisted vs laparoscopic hysterectomy among women with benign gynecologic disease. JAMA 2013;309:689–98.
15. Mäkinen J, Brummer T, Jalkanen J, Heikkinen AM, Fraser J, Tomás E, et al. Ten years of progress—improved hysterectomy outcomes in Finland 1996–2006: a longitudinal observation study. BMJ Open 2013;3:e003169.
16. Ogden CL, Carroll MD, Kit BK, Flegal KM. Prevalence of childhood and adult obesity in the United States, 2011–2012. JAMA 2014;311:806–14.
17. Lethaby A, Vollenhoven B. Fibroids (uterine myomatosis, leiomyomas). BMJ Clin Evid 2011;2011:0814.
18. Okolo S. Incidence, aetiology and epidemiology of uterine fibroids. Best Pract Res Clin Obstet Gynaecol 2008;22:571–88.
19. Benedetto C, Salvagno F, Canuto EM, Gennarelli G. Obesity and female malignancies. Best Pract Res Clin Obstet Gynaecol 2015;29:528–40.
20. Bakkum-Gamez JN, Dowdy SC, Borah BJ, Haas LR, Mariani A, Martin JR, et al. Predictors and costs of surgical site infections in patients with endometrial cancer. Gynecol Oncol 2013;130:100–6.
21. Kumar A, Bakkum-Gamez JN, Weaver AL, McGree ME, Cliby WA. Impact of obesity on surgical and oncologic outcomes in ovarian cancer. Gynecol Oncol 2014;135:19–24.
22. Summitt RL Jr, Stovall TG, Steege JF, Lipscomb GH, A multicenter randomized comparison of laparoscopically assisted vaginal hysterectomy and abdominal hysterectomy in abdominal hysterectomy candidates. Obstet Gynecol 1998;92:321–6.
23. Walsh CA, Walsh SR, Tang TY, Slack M. Total abdominal hysterectomy versus total laparoscopic hysterectomy for benign disease: a meta-analysis. Eur J Obstet Gynecol Reprod Biol 2009;144:3–7.
24. Dowdy SC, Borah BJ, Bakkum-Gamez JN, Kumar S, Weaver AL, McGree ME, et al. Factors predictive of postoperative morbidity and cost in patients with endometrial Cancer. Obstet Gynecol 2012;120:1419–27.
25. Lee MS, Venkatesh KK, Growdon WB, Ecker JL, York-Best CM. Predictors of 30-day readmission following hysterectomy for benign and malignant indications at a tertiary care academic medical center. Am J Obstet Gynecol 2016;214:607.e1–12.
26. Powell LH, Meyer P, Weiss G, Matthews KA, Santoro N, Randolph JF Jr, et al. Ethnic differences in past hysterectomy for benign conditions. Womens Health Issues 2005;15:179–86.
27. Smith LH, Waetjen LE, Paik CK, Xing G. Trends in the safety of inpatient hysterectomy for benign conditions in California, 1991–2004. Obstet Gynecol 2008;112:553–61.
© 2016 by The American College of Obstetricians and Gynecologists. Published by Wolters Kluwer Health, Inc. All rights reserved.
28. Sangi-Haghpeykar H, Poindexter AN III. Epidemiology of endometriosis among parous women. Obstet Gynecol 1995;85:983–92.