Meta-analysis of randomized controlled trials of antibiotic prophylaxis in abdominal hysterectomy

No. 275-Antibiotic Prophylaxis in Gynaecologic Procedures

OBJECTIVE

To review the evidence and provide recommendations on antibiotic prophylaxis for gynaecologic procedures.

OUTCOMES

Outcomes evaluated include need and effectiveness of antibiotics to prevent infections in gynaecologic procedures.

EVIDENCE

Medline and The Cochrane Library were searched for articles published between January 1978 and January 2011 on the topic of antibiotic prophylaxis in gynaecologic procedures. Results were restricted to systematic reviews, randomized control trials/ controlled clinical trials, and observational studies. Searches were updated on a regular basis and incorporated in the guideline to June 2011. Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology assessment-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies.

VALUES

The quality of evidence obtained was rated using the criteria described in the Report of the Canadian Task Force on Preventative Health Care (Table 1).

BENEFITS, HARMS, AND COSTS

Guideline implementation should result in a reduction of cost and related harm of administering antibiotics when not required and a reduction of infection and related morbidities when antibiotics have demonstrated a proven benefit.

RECOMMENDATIONS

Cefazolin as surgical antimicrobial prophylaxis in hysterectomy: A systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

Current practice guidelines recommend cefazolin, cefoxitin, cefotetan, or ampicillin-sulbactam as first-line antibiotic prophylaxis in hysterectomy. We undertook this systematic review and meta-analysis of randomized controlled trials (RCTs) to determine whether cefazolin, with limited antianaerobic spectrum, is as effective in preventing surgical site-infection (SSI) as the other first-choice antimicrobials that have more extensive antianaerobic activity.

METHODS

We searched PubMed, Scopus, Web of Science, Cochrane Central, and EMBASE for relevant randomized controlled trials (RCT) in any language up to January 23, 2018. We only included trials that measured SSI (our primary outcome) defined as superficial, deep, or organ space. We excluded trials of β-lactams no longer in clinical use.

RESULTS

In terms of SSI incidence, cefazolin use was not inferior to its comparator in 12 of 13 individual RCTs included in the analysis. The meta-analysis summary estimate showed a significantly higher SSI risk with cefazolin versus cefoxitin or cefotetan (risk ratio, 1.7; 95% CI, 1.04-2.77; P = .03). However, most studies included nonstandardized dosing and duration of antimicrobial prophylaxis, had indeterminate or high risk of bias, did not include patients with gynecological malignancies, and/or were older RCTs not reflective of current clinical practices.

CONCLUSION

Due to inherent limitations associated with old RCTs with limited relevance to contemporary surgery, an RCT of cefazolin versus regimens with significant antianaerobic spectrum is needed to establish the optimal choice for SSI prevention in hysterectomy.

No 275 - Antibioprophylaxie dans le cadre d'interventions gynécologiques

OBJECTIF

Analyser les données et formuler des recommandations sur l'antibioprophylaxie dans le cadre d'interventions gynécologiques.

ISSUES

Parmi les issues évaluées, on trouvait la nécessité du recours aux antibiotiques et leur efficacité pour ce qui est de la prévention des infections dans le cadre d'interventions gynécologiques. RéSULTATS: Des recherches ont été menées dans Medline et The Cochrane Library afin d'en tirer les articles publiés entre janvier 1978 et janvier 2011 sur le sujet de l'antibioprophylaxie dans le cadre d'interventions gynécologiques. Les résultats ont été restreints aux analyses systématiques, aux essais comparatifs randomisés / essais cliniques comparatifs et aux études observationnelles. Les recherches ont été mises à jour de façon régulière et intégrées à la directive clinique jusqu'en juin 2011. La littérature grise (non publiée) a été identifiée par l'intermédiaire de recherches menées dans les sites Web d'organismes s'intéressant à l'évaluation des technologies dans le domaine de la santé et d'organismes connexes, dans des collections de directives cliniques, dans des registres d'essais cliniques et auprès de sociétés de spécialité médicale nationales et internationales.

VALEURS

La qualité des résultats a été évaluée au moyen des critères décrits dans le rapport du Groupe d'étude canadien sur les soins de santé préventifs (Tableau 1). AVANTAGES, DéSAVANTAGES ET COûTS: La mise en œuvre de la directive clinique devrait entraîner une baisse des coûts et des torts liés à l'administration superflue d'antibiotiques, ainsi qu'une atténuation des infections et des morbidités connexes dans les cas où il a été démontré que l'administration d'antibiotiques confère un avantage pour la patiente. RECOMMANDATIONS.

Antibiotic prophylaxis for elective hysterectomy

BACKGROUND

Elective hysterectomy is commonly performed for benign gynaecological conditions. Hysterectomy can be performed abdominally, laparoscopically, or vaginally, with or without laparoscopic assistance. Antibiotic prophylaxis consists of administration of antibiotics to reduce the rate of postoperative infection, which otherwise affects 40%-50% of women after vaginal hysterectomy, and more than 20% after abdominal hysterectomy. No Cochrane review has systematically assessed evidence on this topic.

OBJECTIVES

To determine the effectiveness and safety of antibiotic prophylaxis in women undergoing elective hysterectomy.

SEARCH METHODS

We searched electronic databases to November 2016 (including the Cochrane Gynaecology and Fertility Group Specialised Register, the Cochrane Central Register of Studies (CRSO), MEDLINE, Embase, PsycINFO, and the Cumulative Index to Nursing and Allied Health Literature (CINAHL), as well as clinical trials registers, conference abstracts, and reference lists of relevant articles.

SELECTION CRITERIA

All randomised controlled trials (RCTs) comparing use of antibiotics versus placebo or other antibiotics as prophylaxis in women undergoing elective hysterectomy.

DATA COLLECTION AND ANALYSIS

We used Cochrane standard methodological procedures.

MAIN RESULTS

We included in this review 37 RCTs, which performed 20 comparisons of various antibiotics versus placebo and versus one another (6079 women). The quality of the evidence ranged from very low to moderate. The main limitations of study findings were risk of bias due to poor reporting of methods, imprecision due to small samples and low event rates, and inadequate reporting of adverse effects. Any antibiotic versus placebo Vaginal hysterectomyModerate-quality evidence shows that women who received antibiotic prophylaxis had fewer total postoperative infections (risk ratio (RR) 0.28, 95% confidence interval (CI) 0.19 to 0.40; five RCTs, N = 610; I2 = 85%), less urinary tract infection (UTI) (RR 0.58, 95% CI 0.43 to 0.77; eight RCTs, N = 1790; I2 = 44%), fewer pelvic infections (RR 0.28, 95% CI 0.20 to 0.39; 11 RCTs, N = 2010; I2 = 57%), and fewer postoperative fevers (RR 0.43, 95% CI 0.34 to 0.54; nine RCTs, N = 1879; I2 = 48%) than women who did not receive such prophylaxis. This suggests that antibiotic prophylaxis reduces the average risk of postoperative infection from about 34% to 7% to 14%. Whether this treatment has led to differences in rates of other serious infection remains unclear (RR 0.20, 95% CI 0.01 to 4.10; one RCT, N = 146; very low-quality evidence).Data were insufficient for comparison of adverse effects. Abdominal hysterectomyWomen who received antibiotic prophylaxis of any class had fewer total postoperative infections (RR 0.16, 95% CI 0.06 to 0.38; one RCT, N = 345; low-quality evidence), abdominal wound infections (RR 0.64, 95% CI 0.45 to 0.92; 11 RCTs, N = 2434; I2 = 0%; moderate-quality evidence), UTIs (RR 0.39, 95% CI 0.29 to 0.51; 11 RCTs, N = 2547; I2 = 26%; moderate-quality evidence), pelvic infections (RR 0.50, 95% CI 0.35 to 0.71; 11 RCTs, N = 1883; I2 = 11%; moderate-quality evidence), and postoperative fevers (RR 0.60, 95% CI 0.51 to 0.70; 11 RCTs, N = 2581; I2 = 51%; moderate-quality evidence) than women who did not receive prophylaxis, suggesting that antibiotic prophylaxis reduces the average risk of postoperative infection from about 16% to 1% to 6%. Whether this treatment has led to differences in rates of other serious infection remains unclear (RR 0.44, 95% CI 0.12 to 1.69; two RCTs, N = 476; I2 = 29%; very low-quality evidence).It is unclear whether rates of adverse effects differed between groups (RR 1.80, 95% CI 0.62 to 5.18; two RCTs, N = 430; I2 = 0%; very low-quality evidence). Head-to-head comparisons between antibiotics Vaginal hysterectomyWe identified four comparisons: cephalosporin versus penicillin (two RCTs, N = 470), cephalosporin versus tetracycline (one RCT, N = 51), antiprotozoal versus lincosamide (one RCT, N = 80), and cephalosporin versus antiprotozoal (one RCT, N = 78). Data show no evidence of differences between groups for any of the primary outcomes, except that fewer cases of total postoperative infection and postoperative fever were reported in women who received cephalosporin than in those who received antiprotozoal.Only one comparison (cephalosporin vs penicillin; two RCTs, N = 451) yielded data on adverse effects and showed no differences between groups. Abdominal hysterectomyWe identified only one comparison: cephalosporin versus penicillin (N = 220). Data show no evidence of differences between groups for any of the primary outcomes. Adverse effects were not reported. Combined antibiotics versus single antibiotics Vaginal hysterectomyWe identified three comparisons: cephalosporin plus antiprotozoal versus cephalosporin (one RCT, N = 78), cephalosporin plus antiprotozoal versus antiprotozoal (one RCT, N = 78), and penicillin plus antiprotozoal versus penicillin (one RCT, N = 230). Data were unavailable for most outcomes, including adverse effects. We found no evidence of differences between groups, except that fewer women receiving cephalosporin with antiprotozoal received a diagnosis of total postoperative infection, UTI, or postoperative fever compared with women receiving antiprotozoal. Abdominal hysterectomyWe identified one comparison (penicillin plus antiprotozoal vs penicillin only; one RCT, N = 230). Whether differences between groups occurred was unclear. Adverse effects were not reported. Comparison of cephalosporins in different regimensSingle small trials addressed dose comparisons and provided no data for most outcomes, including adverse effects. Whether differences between groups occurred was unclear. No trials compared route of administration.The quality of evidence for all head-to-head and dose comparisons was very low owing to very serious imprecision and serious risk of bias related to poor reporting of methods.

AUTHORS' CONCLUSIONS

Antibiotic prophylaxis appears to be effective in preventing postoperative infection in women undergoing elective vaginal or abdominal hysterectomy, regardless of the dose regimen. However, evidence is insufficient to show whether use of prophylactic antibiotics influences rates of adverse effects. Similarly, evidence is insufficient to show which (if any) individual antibiotic, dose regimen, or route of administration is safest and most effective. The most recent studies included in this review were 14 years old at the time of our search. Thus findings from included studies may not reflect current practice in perioperative and postoperative care and may not show locoregional antimicrobial resistance patterns.

Do prophylactic antibiotics in gynecologic surgery prevent postoperative inflammatory complications? A systematic review

PURPOSE

The aim of this study was to systematically review the literature on antibiotic prophylaxis in gynaecologic surgeries to prevent inflammatory complications after gynaecological operations. The study was carried out as a systematic review.

METHODS

Only randomised controlled trials of women undergoing gynaecological surgery were included. The Medline and the Cochrane library databases were searched from 1966 to 2016. The trials must have investigated an antibiotic intervention to prevent an inflammatory complication after gynaecological surgery. Trials were excluded if they were not randomised, uncontrolled or included obstetrical surgery.

RESULTS

Prophylactic antibiotics prevent inflammatory complications after gynaecological surgery. Prophylactic antibiotics are more effective in surgery requiring access to the peritoneal cavity or the vagina. Cefotetan appears to be more capable in preventing the overall inflammatory complication rate than cefoxitin or cefazolin. No benefit has been shown for the combination of antibiotics as prophylaxis. No difference has been shown between the long-term and short-term use of antibiotics. There is no need for the primary use of an anaerobic antibacterial agent.

CONCLUSION

Antibiotics help to prevent postoperative inflammatory complications after major gynecologic surgeries.

Antibiotic prophylaxis in gynaecologic procedures

OBJECTIVE

To review the evidence and provide recommendations on antibiotic prophylaxis for gynaecologic procedures.

OUTCOMES

Outcomes evaluated include need and effectiveness of antibiotics to prevent infections in gynaecologic procedures.

EVIDENCE

Medline and The Cochrane Library were searched for articles published between January 1978 and January 2011 on the topic of antibiotic prophylaxis in gynaecologic procedures. Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies. Searches were updated on a regular basis and incorporated in the guideline to June 2011. Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology assessment-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies.

VALUES

The quality of evidence obtained was rated using the criteria described in the Report of the Canadian Task Force on Preventative Health Care (Table 1).

BENEFITS, HARMS, AND COSTS

Guideline implementation should result in a reduction of cost and related harm of administering antibiotics when not required and a reduction of infection and related morbidities when antibiotics have demonstrated a proven benefit.

RECOMMENDATIONS

(1) All women undergoing an abdominal or vaginal hysterectomy should receive antibiotic prophylaxis. (I-A) (2) All women undergoing laparoscopic hysterectomy or laparoscopically assisted vaginal hysterectomy should receive prophylactic antibiotics. (III-B) (3) The choice of antibiotic for hysterectomy should be a single dose of a first-generation cephalosporin. If patients are allergic to cephalosporin, then clindamycin, erythromycin, or metronidazole should be used. (I-A) (4) Prophylactic antibiotics should be administered 15 to 60 minutes prior to skin incision. No additional doses are recommended. (I-A) (5) If an open abdominal procedure is lengthy (e.g., > 3 hours), or if the estimated blood loss is > 1500 mL, an additional dose of the prophylactic antibiotic may be given 3 to 4 hours after the initial dose. (III-C) (6) Antibiotic prophylaxis is not recommended for laparoscopic procedures that involve no direct access from the abdominal cavity to the uterine cavity or vagina. (l-E) (7) All women undergoing surgery for pelvic organ prolapse and/or stress urinary incontinence should receive a single dose of first-generation cephalosporin. (III-B) (8) Antibiotic prophylaxis is not recommended for hysteroscopic surgery. (II-2D) (9) All women undergoing an induced (therapeutic) surgical abortion should receive prophylactic antibiotics to reduce the risk of post-abortal infection. (I-A) (10) Prophylactic antibiotics are not suggested to reduce infectious morbidity following surgery for a missed or incomplete abortion. (I-E) (11) Antibiotic prophylaxis is not recommended for insertion of an intrauterine device. (I-E) However, health care professionals could consider screening for sexually transmitted infections in high-risk populations. (III-C) (12) There is insufficient evidence to support the use of antibiotic prophylaxis for an endometrial biopsy. (III-L) (13) The best method to prevent infection after hysterosalpingography is unknown. Women with dilated tubes found at the time of hysterosalpingography are at highest risk, and prophylactic antibiotics (e.g., doxycycline) should be given. (II-3B) (14) Antibiotic prophylaxis is not recommended for urodynamic studies in women at low risk, unless the incidence of urinary tract infection post-urodynamics is > 10%. (1-E) (15) In patients with morbid obesity (BMI > 35 kg/m²), doubling the antibiotic dose may be considered. (III-B) (16) Administration of antibiotics solely to prevent endocarditis is not recommended for patients who undergo a genitourinary procedure. (III-E).

Postoperative infections and antibiotic prophylaxis for hysterectomy in Sweden: a study by the Swedish National Register for Gynecologic Surgery

AIM

The purpose of the study was to evaluate the current use of antibiotic prophylaxis, the rate of postoperative infections, and risk factors for postoperative infections in patients undergoing elective hysterectomy for non-malignant pathology.

METHODS

The study was performed during the time period July 2000 to 1 January 1 2003, using data from the Swedish National Register for Gynecologic Surgery, covering 26 of 49 clinics and approximately 50% of the Swedish population. During this time period, 3267 women undergoing elective hysterectomy for non-malignant pathology (mainly dysfunctional bleeding and fibromas) and with complete data on the use of antibiotic prophylaxis and postoperative follow up were included. A postoperative infection was considered to have developed if patients or the physician reported an infection related to the surgical site, together with reported use of antibiotic treatment.

RESULTS

Among the 3267 patients, 341 (10.4%) were considered to have developed a postoperative infection. In cases where antibiotic prophylaxis had not been given, total abdominal hysterectomies and vaginal hysterectomies were associated with the highest frequency for postoperative infections P < 0.05 and P < 0.01, respectively. Notably, also women undergoing subtotal hysterectomy reported significantly lower rates of postoperative infections if prophylactic antibiotics had been given, P < 0.05. Risk factors for postoperative infection were non-use of antibiotic prophylaxis, hospital, age less than 40 years, and BMI > 30 kg/m(2).

CONCLUSIONS

The study results have indicated the need of prospective clinical trials on antibiotic prophylaxis for patients undergoing supravaginal abdominal hysterectomy. Also, a need to further evaluate the current prophylactic antibiotic protocols used for obese patients and younger women undergoing any kind of hysterectomy is warranted.

Revisão sistemática e meta-análise da antibioticoprofilaxia na histerectomia abdominal

O presente estudo objetivou examinar a evidência científica disponível relativa à eficácia da antibioticoprofilaxia no caso da histerectomia, no sentido de subsidiar decisões relativas a financiamento e contribuir para a produção de diretrizes clínicas baseadas em evidências. Usando protocolo previamente elaborado, os ensaios disponíveis foram analisados quanto à pertinência e qualidade. A heterogeneidade clínica dos ensaios selecionados também foi examinada. O teste de heterogeneidade estatística sugeriu que os estudos são homogêneos, considerando-se o valor de p > 0,10 como nível de significância para rejeitar a heterogeneidade. A combinação dos resultados dos 16 ensaios placebo-controlados selecionados resultou em razão de taxas sumárias de 0,49 (IC95%: 0,41-0,59), ou seja, em eficácia de 51%, e em diferença de taxas sumárias de 11% (IC95%: 8-14%), utilizando-se o modelo de efeitos fixos. Os resultados observados usando-se o modelo de efeitos aleatórios foram muito semelhantes. A análise exploratória de esquemas de dose única versus doses múltiplas não indicou maior eficácia para esquemas de doses múltiplas. A evidência disponível, baseando-se em ensaios comparativos, é insuficiente para inferir que existe vantagem em usar cefalosporinas de terceira geração frente àquelas de primeira.

[Antibiotic prophylaxis in gynecologic surgery]

Hysterectomies are contaminated procedures; surgical wound related sepsis ranges from 10 to 25%. Several randomised controlled studies demonstrated a significant benefit with prophylactic antibiotics. The study results were more controversial for abdominal hysterectomies. Ureidopenicillins, cephamycins and other antibacterial agents active on Gram negative rods and anaerobes can be recommended as a preoperative flash at anaesthesia induction, followed by a second injection whenever the procedure duration exceeds 3 hours. In case of extended hysterectomy for cancer, broad spectrum antibiotic prophylaxis is usual; some recent studies demonstrated the efficacy of a short duration antibacterial agent use. Mastectomies are at low risk for postoperative infection. Antibacterial prophylaxis is common, especially in plastic surgery.

Should uterine size be an indication for surgical intervention in women with myomas?

The quality assurance guidelines published by the American College of Obstetricians and Gynecologists advocate hysterectomy for women with fibroids once the size of the uterus equals or exceeds that at 12 weeks of gestation, regardless of the presence or absence of significant symptoms. Reasons frequently cited by gynecologists for the necessity for surgical intervention include (1) the inability to examine the ovaries, (2) the possible malignancy of the enlarged pelvic mass, (3) the potential for compromise of adjacent organ function if uterine or myomatous growth continues, (4) the greater risks of future surgical treatment if uterine or myomatous growth continues, (5) the potential for greater fertility after surgery on a smaller uterus, and (6) the possibility of continued uterine or myomatous growth resulting from hormone replacement therapy after menopause. A review of the literature reveals surprisingly scant data supporting each of these indications for surgical intervention. The availability of high-resolution ultrasonography and magnetic resonance imaging allows for expectant management in many cases where the uterus is at least 12 gestational weeks in size. The presence and severity of myoma-related symptoms should be the most important considerations in the individualization of treatment strategies.

Antibiotic prophylaxis in abdominal hysterectomy, with special reference to the duration of the prophylaxis

Two consecutive open studies were performed of the efficacy of a prophylactic cefuroxime/metronidazole combination in abdominal hysterectomy. The first group received a 24-h regimen, the second group a single pre-operative dose. The incidence of post-operative wound infections and urinary tract infections were similar in both groups [wound infections in 1/75 versus 2/84 patients (NS), urinary tract infections 4/75 versus 3/84 patients (NS), respectively, in the 24-h group and single-dose group]. No significant differences in other parameters, such as pyrexia and duration of post-operative hospitalization, could be detected.

Single-dose prophylaxis in hysterectomies. An interim analysis

The efficacy of single-dose prophylaxis with intravenous cefuroxime 1,500 mg plus 500 mg metronidazole in vaginal or abdominal hysterectomies was investigated in a randomized, double-blind, placebo-controlled study, involving 396 evaluable patients. A significant reduction of the number in urinary tract infections was observed in the groups undergoing abdominal hysterectomy or vaginal hysterectomy with vaginal repair. The incidence of wound infections and the duration of hospitalization were significantly reduced in patients undergoing vaginal hysterectomy with or without vaginal repair. Body temperature normalized faster in all three groups receiving peri-operative antibiotic prophylaxis. It is concluded that a single injection of antimicrobial prophylaxis is sufficient and useful in both abdominal and vaginal hysterectomies.