Here are several ways to help keep quality up and costs down for this common procedure.
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There are several ways to help keep quality up and costly complications down for one of health care's most frequently performed procedures. The list includes reducing UTIs, blood loss, and operative time and shortening length of stay through careful patient selection and use of minimally invasive techniques when appropriate.
In 1985, nearly one of every five females in the United States over age 15 had undergone a hysterectomy.1 Even today, hysterectomy is still one of the most frequently performed procedures in this countrywhich is why its costly complications can really add up.
Although few women die from the operation, it often exacts a needlessly high physical and financial cost in terms of surgery-related complications and associated co-morbid conditions that extend hospital stays, drive up costs, and tax our health-care resources. But by finding better ways to measure and identify health-care quality and cost, and routinely implementing them, we can keep complications from getting out of hand. This in turn, will rein in costs as health-care providers, consumers, purchasers, and policy makers are increasingly demanding (see "Measuring hysterectomy-related morbidity").1 Our goal is to review current trends in hysterectomy and morbidity stemming from its complications and give practical suggestions for avoiding or reducing them. That in turn should help reduce the procedure's direct and indirect costs.
For the past 20 years, the median age of hysterectomy patients has remained 41 years.1,2 Although 60% to 75% of procedures are performed by the traditional abdominal route, the trend is to vaginal and laparoscopic routes (Figure 1).1-3 During that same period, indications for hysterectomy have remained fairly stable. Some 27% to 28% of patients undergo the procedure for fibroids, 14% to 21% for prolapse, 11% to 15% for endometriosis, 9% to 15% for pre-cancerous or cancerous cervical conditions, and the remaining 20% for other indications.2,4
One method of studying comorbidity in groups of patients undergoing procedures is the Charlson comorbidity index (CCI), a weighted index used with administrative databases that correlates with inpatient mortality. We recently noted a higher average CCI in endometrial cancer patients with post-hysterectomy complications versus those without.5 Overall frequency of complications was 26%, compared with the 16% reported by Myers and Steege, and the total charges and lengths of stay (LOS) of patients with complications were 1.6-fold higher. 5 Multivariate analysis determined that the following factors seemed to substantially increase total charges over and above their effect on LOS: older age, complications, CCI, radical hysterectomy, and lymph-node dissection. Moreover, the type of complication determined how extensively complications drove up charges. For example, multistage regression analysis (which separates indirect effects of an independent variable from direct effects) showed that complications elevated charges as follows: for cardiac complication: an additional $2,949; for pulmonary embolus: an extra $5,158; for anemia due to blood loss: an added $2,475; while respiratory complications drove up costs a hefty $24,980.6
Although types of comorbidity on the CCI also include obesity, age, and a cancer diagnosis, cardiac and pulmonary disease are most likely to predict postoperative morbidity.6-9 Cancer-specific complications include thromboembolic events, hemorrhage, and injury to adjacent organs.
An estimated 97 million adults in the US55% of the populationare overweight or obese (defined as body mass index [BMI] >25).10-12 Operative-site infection and unexplained fever occurred in 11% of obese patients compared with 4% of normal-weight patients undergoing elective noncardiac surgery. Although the rate of infection in obese women may be influenced by the type of incision and length ofprocedure, previous authors notea higher rate of wound infection in obese patients compared with patients of normal weight.13,14 Although no correlation was found between BMI and LOS, BMI correlated significantly with hospitalization costs. When overweight patients had surgery, the total damage in dollars was $3,150 higher than for patients of normal weight.10 Diabetes and hypertension seem to increase an obese patient's risk of complications.15
The current trend towards laparoscopic hysterectomy (Figure 1) has prompted many studies of complications.16 A 1997 population-based study found that about one in 100 Finnish women who had undergone that procedure suffered vascular injuries (1.2%) and infections (5.6%).3 The rate of acute bowel complications (0.4%) was similarto that for abdominal or vaginal routes, but the rate of urinary tract injuries (2.7%) was 16-fold higher. Subsequent repair of injuries tended to lead to additional surgery and extended recovery time. Later data analysis revealed half the ureteral complication rate in the second phase of the study, reflecting the role of the surgeon's "learning curve" in reducing complications.3
Although previous studies indicate that laparoscopic-assisted vaginal hysterectomy (LAVH) involves a shorter hospital stay, speedier postoperative recovery, and less analgesia, a review of the literature in 1997 indicated a fourfold higher rate of bladder injury and lengthier operative times.17 A subsequent report in 1998 indicated a 34-fold higher incidence of ureteral injury with LAVH compared with other routes.18 A more recent study randomized 541 women to either a vaginal approach to colpotomy versus laparoscopic-assisted abdominal colpotomy in performing LAVH. These authors determined a tenfold lower rate of urinary tract injury in the group of women who underwent the vaginal approach to colpotomy.19 More prospective longitudinal studies are needed to assess true morbidity rates.
The rates of unplanned additional major surgical procedures are reported to be 3% with LAVH with the rate of bowel injury at 1.9/1,000.4,7,20 Although the risk of long-term bowel-related complications related to adhesions is higher with abdominal surgery than with vaginal surgery, there are few reports in the gynecologic literature that evaluate this issue.21 Data from the general surgical literature indicate that the overall rate of late complications for patients undergoing gastrointestinal procedures via the laparoscopic approach is 5.4%.22
Complications and comorbidity may drive up both direct costs of treating the complication and indirect costs due to extended LOS and added services required after discharge. Few studies evaluate indirect or patient costs, but it's implied that procedures that involve a shorter recovery time and hospital stay will translate into lower costs overall. While LAVH generally incurs higher operating room costs, most are offset by the shorter LOS.6,21,23 Magrina and colleagues revealed the importance of longitudinal follow up in their review of 56 women who underwent laparoscopic lymphadenectomy with vaginal or laparoscopic hysterectomy and bilateral salpingo-oophorectomy.24 Intraoperative complications occurred in 7% and transformation to laparotomy was necessary in 12% of patients. Although their sample size was limited, they observed a 3-year cause-specific survival that was similar to patients treated by an abdominal approach.
Others report major complications in 2% to 4% of LAVHs. Leng and colleagues determined that one third of all complications were associated with the insertion of a Veress needle or trocar (emphysema, vascular injury).25 Other complications included bowel obstruction, ureteric fistula, bleeding, bladder or bowel injuries, burn injuries due to malfunctioning equipment, nerve paresis, and febrile morbidity. Table 1 lists common complications associated with hysterectomy and gives practical strategies to reduce them, supported by a brief review of the literature.
|Febrile morbidity||(A) Prevent fever through antibiotic prophylaxis; single dose first- or second-generation cephalosporin.|
|Urinary tract infections||Remove Foley catheter <24 hours after abdominal hysterectomy. Consider intermittent catheterization as an alternative to long-term catheterization.|
|Length of stay||Get your patients up and walking. Early ambulation and diet reduced LOS in patients undergoing laparotomy and intestinal resection.|
|Blood loss||Determine which patients will benefit from a LAVH. In selected patients, one study showed that blood loss was significantly lower in LAVH vs. abdominal hysterectomy.|
|Operative time||Avoid closure of the peritoneum.|
|Bowel and vascular injury||In a randomized trial, liquid sodium phosphate was found to be more effective and better tolerated than sodium phosphate tablets for patients requiring bowel preparation prior to surgery.|
|Ureteral injuries infundibulopelvic ligament||(A) Optimize exposure and visualize ureter before ligating the ovarian artery and vein. (B) Pair experienced surgeons with trainees. (C) Keep in mind that ureteral and bowel injuries are less common among surgeons who have performed more than 30 LAVHs, compared to those who have performed fewer. (D) Consider Munro Type II operation.|
| cardinal ligament||(A) Stop laparoscopic dissection after coagulating uterine vascular bundles. (B) Identify ureter prior to coagulation when obtaining hemostasis.|
|Venous thromboembolism||(A) Use minidose subcutaneous heparin to prevent pulmonary embolus in surgical patients. May increase risk of bleeding. (B) Use pneumatic compression devices. (C) Give low-molecular-weight heparin (LMWH) dalteparin 2,500 U, 1 to 2 hours preop, again in 12 hours, and then 5,000 U q day for 5 days or until discharge. No excess risk of bleeding. (D) Be aware that patients with cancer, a history of DVT, or older than age 60 may require more intensive prophylaxis programs and have been identified as least likely to respond to intermittent pneumatic compression. These patients may require more intensive prophylaxis programs.|
|Risk of ileus||(A) Start early feeding after major gynecologic surgery, which decreases LOS. While it may result in emesis, it does not increase the incidence of aspiration pneumonia, dehiscence, or intestinal leaks.|
|Risk of neurovascular injury with lithotomy position||Pay careful attention to positioning, periodic monitoring, and repositioning, when feasible, as these measures may reduce risk. This may avoid a variety of neurovascular complications, including lumbosacral plexus stretch, sciatic and peroneal nerve injury, and compartment syndrome of the legs.|
1. Tanos V, Rojansky N. Prophylactic antibiotics in abdominal hysterectomy. J Am Coll Surg. 1994;179:593-600.
2. Wttewaall-Evelaar EW. Meta-analysis of randomized controlled trials of antibiotic prophylaxis in abdominal hysterectomy.Pharm Week Sci. 1990;12:296-298.
3. Soper DE, Yarwood RL. Single-dose antibiotic prophylaxis in women undergoing vaginal hysterectomy. Obstet Gynecol. 1987;69:879-882.
4. Chongsomchai C, Lumbiganon P, Thinkhamrop J, et al. Placebo-controlled, double-blind, randomized study of prophylactic antibiotics in elective abdominal hysterectomy. J Hosp Infect. 2002;52:302-306.
5. Larsson PG, Platz-Christensen JJ, Forsum U, et al. Clue cells in predicting infections after abdominal hysterectomy. Obstet Gynecol. 1991;77:450-452.
6. Persson E, Bergstrom M, Larsson PG, et al. Infections after hysterectomy. A prospective nationwide Swedish study. The Study Group on Infectious Diseases in Obstetrics and Gynecology within the Swedish Society of Obstetrics and Gynecology. Acta Obstet Gynecol Scand. 1996;75:757-761.
7. Soper DE, Bump RC, Hurt WG. Bacterial vaginosis and trichomoniasis vaginitis are risk factors for cuff cellulitis after abdominal hysterectomy. Am J Obstet Gynecol. 1990;163:1016-1021.
8. Soper DE. Bacterial vaginosis and postoperative infections.Am J Obstet Gynecol. 1993;169:467-469.
9. Toglia MR, Pearlman MD. Pelvic fluid collections following hysterectomy and their relation to febrile morbidity. Obstet Gynecol. 1994;83:766-770.
10. Summitt RL Jr, Stovall TG, Bran DF. Prospective comparison of indwelling bladder catheter drainage versus no catheter after vaginal hysterectomy. Am J Obstet Gynecol. 1994;170:1815-1818.
11. Dobbs SP, Jackson SR, Wilson AM, et al. A prospective, randomized trial comparing continuous bladder drainage with catheterization at abdominal hysterectomy. Br J Urol. 1997;80:554-556.
12. Chamberlain DH, Hopkins MP, Roberts JA, et al. The effects of early removal of indwelling urinary catheter after radical hysterectomy. Gynecol Oncol. 1991;43:98-102.
13. Delaney CP, Zutshi M, Senagore AJ, et al. Prospective, randomized, controlled trial between a pathway of controlled rehabilitation with early ambulation and diet and traditional postoperative care after laparotomy and intestinal resection. Dis Colon Rectum. 2003;46:851-859.
14. Marana R, Busacca M, Zupi E, et al. Laparoscopically assisted vaginal hysterectomy versus total abdominal hysterectomy: a prospective, randomized, multicenter study. Am J Obstet Gynecol. 1999;180:270-275.
15. Gupta JK, Dinas K, Khan KS. To peritonealize or not to peritonealize? A randomized trial at abdominal hysterectomy. Am J Obstet Gynecol. 1998;178:796-800.
16. Balaban DH, Leavell BS Jr, Oblinger MJ, et al. Low volume bowel preparation for colonoscopy: randomized, endoscopist-blinded trial of liquid sodium phosphate versus tablet sodium phosphate. Am J Gastroenterol. 2003;98:827-832.
17. Kaloo P, Cooper M, Molloy D. A survey of entry techniques and complications of members of the Australian Gynaecological Endoscopy Society. Aust N Z J Obstet Gynaecol. 2002;42:264-266.
18. Makinen J, Johansson J, Tomas C, et al. Morbidity of 10 110 hysterectomies by type of approach. Hum Reprod. 2001;16:1473-1478.
19. Tamussino KF, Lang PF, Breinl E. Ureteral complications with operative gynecologic laparoscopy. Am J Obstet Gynecol. 1998;178:967-970.
20. Neuman M, Eidelman A, Langer R, et al. Iatrogenic injuries to the ureter during gynecologic and obstetric operations. Surg Gynecol Obstet. 1991;173:268-272.
21. Kakkar VV, Corrigan TP, Fossard DP. Prevention of fatal postoperative pulmonary embolism by low doses of heparin. Lancet. 1975;2:45-51.
22. Maxwell GL, Synan I, Dodge R, et al. Pneumatic compression versus low molecular weight heparin in gynecologic oncology surgery: a randomized trial. Obstet Gynecol. 2001;98:989-995.
23. Clarke-Pearson DL, Dodge RK, Synan I, et al. Venous thromboembolism prophylaxis: patients at high risk to fail intermittent pneumatic compression. Obstet Gynecol. 2003;101:157-163.
24. Fanning J, Andrews S. Early postoperative feeding after major gynecologic surgery: evidence-based scientific medicine. Am J Obstet Gynecol. 2001;185:1-4.
25. Han-Geurts IJ, Jeekel J, Tilanus HW, et al. Randomized clinical trial of patient-controlled versus fixed regimen feeding after elective abdominal surgery. Br J Surg. 2001;88:1578-1582.
26. MacMillan SL, Kammerer-Doak D, Rogers RG, et al. Early feeding and the incidence of gastrointestinal symptoms after major gynecologic surgery. Obstet Gynecol. 2000;96:604-608.
27. Taguchi A, Sharma N, Saleem RM, et al. Selective postoperative inhibition of gastrointestinal opioid receptors. N Engl J Med. 2001;345:935-940.
28. Hershlag A, Loy RA, Lavy G, et al. Femoral neuropathy after laparoscopy. A case report. J Reprod Med. 1990;35:575-576.
29. Herrera-Ornelas L, Tolls RM, Petrelli NJ, et al. Common peroneal nerve palsy associated with pelvic surgery for cancer. An analysis of 11 cases. Dis Colon Rectum. 1986;29:392-397.
As we recently reported, the overall LOS for women undergoing abdominal hysterectomy for endometrial cancer in 1996 was 5 days compared to 3 days for vaginal hysterectomy patients and 2.6 days for women undergoing vaginal hysterectomy and laparoscopy.6 Patients undergoing vaginal hysterectomy and lymph-node dissection averaged 4 days. LOS continues to shorten each year, and the figures today are all a far cry from the 12-day LOS back in 1965 and even the 7 days reported for 1984.2 For patients remaining in the hospital more than 2 days, inpatient charges make up the bulk of hospital charges. Third-party payers should recognize that age continues to be a major contributor to LOS, as do complications and type of procedure.6,8,26
Our goal has been to suggest practical strategies to reduce hysterectomy-related comorbidity and complications. The studies we've summarized provide a framework for future prospective population-based studies, but additional longitudinal data are also needed. Widespread implementation of such analyses would allow physicians to monitor procedures and demonstrate quality of care and cost assessment to third parties and other organizations.27 In the meantime, the ob/gyn in the trenches can make a small dent in containing costly complications through some of the strategies outlined in Table 1.
1. Myers ER, Steege JF. Risk adjustment for complications of hysterectomy: limitations of routinely collected administrative data. Am J Obstet Gynecol. 1999;181:567-575.
2. Pokras R, Hufnagel V. Hysterectomies in the United States, 1965-1984. In: Vital and Health Statistics, Series 13, No. 92. Hyattsville, Md: US Dept. of Health and Human Services, Public Health Service, Centers for Disease Control, National Center for Health Statistics, 1987.
3. Harkki-Siren P, Sjoberg J, Makinen J, et al. Finnish national register of laparoscopic hysterectomies: a review and complications of 1165 operations. Am J Obstet Gynecol. 1997;176:118-122.
4. Gambone JC, Reiter R, Lench JB. Quality assurance indicators and short-term outcome of hysterectomy. Obstet Gynecol. 1990;76:841-844.
5. Franchi M, Ghezzi F, Riva C, et al. Postoperative complications after pelvic lymphadenectomy for the surgical staging of endometrial cancer. J Surg Oncol. 2001;78:232-237.
6. Brooks SE, Ahn J, Mullins CD, et al. Health care cost and utilization project analysis of comorbid illness and complications for patients undergoing hysterectomy for endometrial carcinoma. Cancer. 2001;92:950-958.
7. Browne DS, Frazier MI. Hysterectomy revisited. Aust N Z J Obstet Gynaecol. 1991;31:148-152.
8. Brooks SE, Ahn J, Mullins CD, et al. Resource and use of the intensive care unit in patients who undergo surgery for ovarian carcinoma.Cancer. 2002;95:1457-1462.
9. Brooks SE, Mullins CD, Guo C, et al. Resource utilization for patients undergoing hysterectomy with or without lymph node dissection for endometrial cancer. Gynecol Oncol. 2002;85:242-249.
10. Thomas EJ, Goldman L, Mangione CM, et al. Body mass index as a correlate of postoperative complications and resource utilization.Am J Med. 1997;102:277-283.
11. National Heart, Lung and Blood Institute. The Practical Guide: Identification, Evaluation and Treatment of Overweight and Obesity in Adults. Bethesda, MD: National Institutes of Health; 1998.
12. Douketis JD, Feightner JW, Attia J, et al. Periodic health examination, 1999 update: 1. Detection, prevention, and treatment of obesity. Canadian Task Force on Preventive Health. CMAJ. 1999;160:513-525.
13. Tsukada K, Miyazaki T, Kato H, et al. Body fat accumulation and postoperative complications after abdominal surgery. Am Surg. 2004;70:347-351.
14. Thomas EJ, Goldman L, Mangione CM, et al. Body mass index as a correlate of postoperative complications and resource utilization.Am J Med. 1997;102:277-283.
15. Kovac SR. Intramyometrial coring as an adjunct to vaginal hysterectomy. Obstet Gynecol. 1986;67:131-136.
16. Farquhar CM, Steiner CA. Hysterectomy rates in the United States 1990-1997. Obstet Gynecol. 2002;99:229-234.
17. Meikle SF, Nugent EW, Orleans M. Complications and recovery from laparoscopy-assisted vaginal hysterectomy compared with abdominal and vaginal hysterectomy. Obstet Gynecol. 1997;89:304-311.
18. Harkki-Siren P, Sjoberg J, Tiitinen A. Urinary tract injuries after hysterectomy. Obstet Gynecol. 1998;92:113-118.
19. Horng SG, Huang KG, Lo TS, et al. Bladder injury after LAVH: a prospective, randomized comparison of vaginal and laparoscopic approaches to colpotomy during LAVH. J Am Assoc Gynecol Laparosc. 2004;11:42-46.
20. Shen CC, Wu MP, Lu CH, et al. Small intestine injury in laparoscopic-assisted vaginal hysterectomy. J Am Assoc Gynecol Laparosc. 2003;10:350-355.
21. Chapron C, Fernandez B, Dubuisson JB. Total hysterectomy for benign pathologies: direct costs comparison between laparoscopic and abdominal hysterectomy. Eur J Obstet Gynecol Reprod Biol. 2000;89:141-147.
22. Polliand C, Barrat C, Raselli R, et al. Colorectal cancer: 74 patients treated by laparoscopic resection with a mean follow-up of 5 years. Ann Chir. 2002;127:690-696.
23. Spirtos N, Schlaerth JB, Gross GM, et al. Cost and quality-of-life analyses of surgery for early endometrial cancer: laparotomy versus laparoscopy. Am J Obstet Gynecol. 1996;174:1795-1799.
24. Magrina JF, Mutone NF, Weaver AL, et al. Laparoscopic lymphadenectomy and vaginal or laparoscopic hysterectomy with bilateral salpingo-oophorectomy for endometrial cancer: morbidity and survival. Am J Obstet Gynecol. 1999;181:376-381.
25. Leng J, Lang J, Huang R, et al. Complications in laparoscopic gynecologic surgery. Chin Med Sci J. 2000;15:222-226.
26. Geisler JP, Geisler HE. Radical hysterectomy in the elderly female: a comparison to patients age 50 or younger. Gynecol Oncol. 2001;80:258-261.
27. Kennedy AW, Austin JM Jr, Look KY, et al. The Society of Gynecologic Oncologists Outcomes Task Force. Study of endometrial cancer: initial experiences. Gynecol Oncol. 2000;9:379-398.
Getting a handle on the high price tag of comorbidity and complications begins with finding a reliable way to measure them. In 1982, the Collaborative Review of Sterilization group (CREST) sponsored by the Centers for Disease Control and Prevention, set up a framework for categorizing complications through a prospective observational study of nine institutions from 1978 to 1981.1,2 CREST classified morbidity as fever, hemorrhage, unintended major surgical procedures, life-threatening events, and re-hospitalization. They put the major morbidity associated with abdominal hysterectomy (predominantly fever and hemorrhage) at 37%.
In 1989, The American College of Obstetricians and Gynecologists established two groups of quality indicators for hysterectomy that are now considered benchmarks for surgical morbidity studies (Table A)2: those intended to identify morbidity (with a 99% overall accuracy) and those intended to screen for appropriateness of care (83% overall accuracy).3,4 In 1995, in reviewing 13 years' worth of post-CREST report studies, investigators determined that although transfusion rates had declined two- to tenfold from 1982 to 1995, bladder injuries had doubled or tripled, with an injury rate of 1% to 2% in recent studies.2,5,6 The rise, they felt, could be due to a higher rate of previous cesarean deliveries in women undergoing hysterectomyor to the fact that the eligibility criteria for vaginal hysterectomy had been expanded to include uterine fibroids and patients without pelvic prolapse.7 The rates of ureteral injury for abdominal or vaginal hysterectomy for benign disease (about 0.2%) seem to have held steady over the past 20 years, in contrast to higher rates for laparoscopic surgeries or procedures for malignancy or other pelvic disease. Vesicovaginal fistula is a rare complication of hysterectomy. Additionally, the rate of unintended major surgical procedures (for example, cystotomy repair, ureteroneocystotomy, bowel resection) has remained approximately 4% to 5% over the past 20 years.7
Admission following a return Emergency Room visit
No infection upon admission/Antibiotics begun after 24 hours
Postoperative transfusion for anemia (Hgb <8 g)
Readmission within 2 weeks
Unforeseen admission to the Intensive Care Unit
Unplanned injury, repair, or removal of organ
Unplanned repeat operation
Appropriateness of care
Diagnosis that pathology report fails to confirm
Hysterectomy on woman younger than age 30
Removal of uterus < 280 g due to fibroids
Source: Adapted from Gambone JC, et al.2
Population-based data on rates of medical and surgical complications provide truer estimates than do single-institution studies. Although administrative data like ICD-9 codes would appear to be ideally suited to such studies, administrative data have limitations as the sole indicator of quality of care. Among more than 107,000 women in North Carolina undergoing hysterectomy between 1988 and 1994, 12% had surgical complications and 7% had medical complications. Concluding that ICD-9 codes better predicted medical than surgical complications, investigators caution against using administrative data to estimate the prevalence of surgical complications, in that it was not possible to extract data such as obesity, prior surgery, uterine size, etc.8 Thus, although a population-based perspective is ideal, administrative data are retrospective and the potential for underreporting exists.
1. Dicker RC, Greenspan JR, Strauss LT, et al. Complications of abdominal and vaginal hysterectomy among women of reproductive age in the United States. The Collaborative Review of Sterilization. Am J Obstet Gynecol. 1982;144:841-848.
2. Gambone JC, Reiter R, Lench JB. Quality assurance indicators and short-term outcome of hysterectomy. Obstet Gynecol. 1990;76:841-845.
3. American College of Obstetricians and Gynecologists, Task Force on Quality Assurance. Quality assurance in obstetrics and gynecology. American College of Obstetricians and Gynecologists, Washington, DC: 1989.
4. Gambone JC, Reiter RC, Lench JB. The impact of a quality assurance process on the frequency and confirmation rate of hysterectomy. Am J Obstet Gynecol. 1990;163:545-550.
5. Kovac SR. Intramyometrial coring as an adjunct to vaginal hysterectomy. Obstet Gynecol. 1986;67:131-136.
6. Browne DS, Frazier MI. Hysterectomy revisited. Aust N Z J Obstet Gynaecol. 1991;31:148-152.
7. Harris WJ. Early complications of abdominal and vaginal hysterectomy. Obstet Gynecol Surv. 1995;50:795-805.
8. Myers ER, Steege JF. Risk adjustment for complications of hysterectomy: limitations of routinely collected administrative data. Am J Obstet Gynecol. 1999;181:567-575.
Sandra Brooks. Cutting hysterectomy-related complications and costs. Contemporary Ob/Gyn Sep. 1, 2004;49:60-68.