Antibiotic prophylaxis for hysterectomy and cesarean section: Amoxicillin-clavulanic acid versus cefazolin

Rational use of antibiotics for major elective gynaecological and obstetrical surgical procedures: quality improvement journey from a tertiary care public facility

BACKGROUND

Antibiotic resistance is a global problem. Irrational use of antibiotics is rampant. Guidelines recommend administration of single dose of antibiotic for surgical antimicrobial prophylaxis (SSAP) for elective obstetrical and gynaecological surgeries. However, it is not usually adhered to in practice. Majority of women undergoing elective major gynaecological surgeries and caesarean sections in the department of obstetrics and gynaecology of our tertiary level heavy case load public health facility were receiving therapeutic antibiotics (for 7-10 days) instead of recommended SSAP. Our aim was to increase the SSAP in our setting from a baseline 2.1% to more than 60% within 6 months.

METHODS

After root cause analysis, we formulated the departmental antimicrobial policy, spread awareness and sensitised doctors and nursing officers regarding antimicrobial resistance and asepsis through lectures, group discussions and workshops. We initiated SSAP policy for elective major surgeries and formed an antimicrobial stewardship team to ensure adherence to policy and follow processes and outcomes. The point of care quality improvement (QI) methodology was used. Percentage of patients receiving SSAP out of all low-risk women undergoing elective surgery was the process indicator and percentage of patients developing surgical site infection (SSI) of all patients receiving SSAP was the outcome indicator. The impact of various interventions on these indicators was followed over time with run charts.

RESULTS

SSAP increased from a baseline 2.1%-67.7% within 6 months of initiation of this QI initiative and has since been sustained at 80%-90% for more than 2 years without any increase in SSI rate.

CONCLUSION

QI methods can rapidly improve the acceptance and adherence to evidence-based guidelines in a busy public healthcare setting to prevent injudicious use of antibiotics.

Different classes of antibiotics given to women routinely for preventing infection at caesarean section

BACKGROUND

Caesarean section increases the risk of postpartum infection for women and prophylactic antibiotics have been shown to reduce the incidence; however, there are adverse effects. It is important to identify the most effective class of antibiotics to use and those with the least adverse effects.  OBJECTIVES: To determine, from the best available evidence, the balance of benefits and harms between different classes of antibiotic given prophylactically to women undergoing caesarean section, considering their effectiveness in reducing infectious complications for women and adverse effects on both mother and infant.

SEARCH METHODS

For this 2020 update, we searched Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP) (2 December 2019), and reference lists of retrieved studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing different classes of prophylactic antibiotics given to women undergoing caesarean section.  RCTs published in abstract form were also included. We excluded trials that compared drugs with placebo or drugs within a specific class; these are assessed in other Cochrane Reviews. We excluded quasi-RCTs and cross-over trials. Cluster-RCTs were eligible for inclusion but none were identified.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the studies for inclusion, assessed risk of bias and carried out data extraction. We assessed the certainty of the evidence using the GRADE approach.

MAIN RESULTS

We included 39 studies, with 33 providing data (8073 women). Thirty-two studies (7690 women) contributing data administered antibiotics systemically, while one study (383 women) used lavage and was analysed separately. We identified three main comparisons that addressed clinically important questions on antibiotics at caesarean section (all systemic administration), but we only found studies for one comparison, 'antistaphylococcal cephalosporins (1st and 2nd generation) versus broad spectrum penicillins plus betalactamase inhibitors'.   We found no studies for the following comparisons: 'antistaphylococcal cephalosporins (1st and 2nd generation) versus lincosamides' and 'antistaphylococcal cephalosporins (1st and 2nd generation) versus lincosamides plus aminoglycosides'. Twenty-seven studies (22 provided data) included comparisons of cephalosporins (only) versus penicillins (only). However for this update, we only pooled data relating to different sub-classes of penicillins and cephalosporins where they are known to have similar spectra of action against agents likely to cause infection at caesarean section. Eight trials, providing data on 1540 women, reported on our main comparison, 'antistaphylococcal cephalosporins (1st and 2nd generation) versus broad spectrum penicillins plus betalactamase inhibitors'. We found data on four other comparisons of cephalosporins (only) versus penicillins (only) using systemic administration: antistaphylococcal cephalosporins (1st and 2nd generation) versus non-antistaphylococcal penicillins (natural and broad spectrum) (9 studies, 3093 women); minimally antistaphylococcal cephalosporins (3rd generation) versus non-antistaphylococcal penicillins (natural and broad spectrum) (4 studies, 854 women); minimally antistaphylococcal cephalosporins (3rd generation) versus broad spectrum penicillins plus betalactamase inhibitors (2 studies, 865 women); and minimally antistaphylococcal cephalosporins (3rd generation) versus broad spectrum and antistaphylococcal penicillins (1 study, 200 women). For other comparisons of different classes of antibiotics, only a small number of trials provided data for each comparison, and in all but one case data were not pooled. For all comparisons, there was a lack of good quality data and important outcomes often included few women. Three of the studies that contributed data were undertaken with drug company funding, one was funded by the hospital, and for all other studies the funding source was not reported. Most of the studies were at unclear risk of selection bias, reporting bias and other biases, partly due to the inclusion of many older trials where trial reports did not provide sufficient methodological information. We undertook GRADE assessment on the only main comparison reported by the included studies, antistaphylococcal cephalosporins (1st and 2nd generation) versus broad spectrum penicillins plus betalactamase inhibitors, and the certainty ranged from low to very low, mostly due to concerns about risk of bias, wide confidence intervals (CI), and few events. In terms of the primary outcomes for our main comparison of 'antistaphylococcal cephalosporins (1st and 2nd generation) versus broad spectrum penicillins plus betalactamase inhibitors': only one small study reported sepsis, and there were too few events to identify clear differences between the drugs (risk ratio (RR) 2.37, 95% CI 0.10 to 56.41, 1 study, 75 women, very low-certainty evidence). There may be little or no difference between these antibiotics in preventing endometritis (RR 1.10; 95% CI 0.76 to 1.60, 7 studies, 1161 women; low-certainty evidence). None of the included studies reported on infant sepsis or infant oral thrush. For our secondary outcomes, we found there may be little or no difference between interventions for maternal fever (RR 1.07, 95% CI 0.65 to 1.75, 3 studies, 678 women; low-certainty evidence). We are uncertain of the effects on maternal: wound infection (RR 0.78, 95% CI 0.32 to 1.90, 4 studies, 543 women), urinary tract infection (average RR 0.64, 95% CI 0.11 to 3.73, 4 studies, 496 women), composite adverse effects (RR 0.96, 95% CI 0.09 to 10.50, 2 studies, 468 women), and skin rash (RR 1.08, 95% CI 0.28 to 4.1, 3 studies, 591 women) (all very low certainty evidence). Although maternal allergic reactions were reported by two studies, there were no events. There were no infant outcomes reported in the included studies. For the other comparisons, the results for most outcomes had wide CIs, few studies and few women included. None of the included trials reported on longer-term maternal outcomes, or on any infant outcomes.

AUTHORS' CONCLUSIONS

Based on the best currently available evidence, 'antistaphylococcal cephalosporins' and 'broad spectrum penicillins plus betalactamase inhibitors' may have similar efficacy at caesarean section when considering immediate postoperative infection, although we did not have clear evidence for several important outcomes. Most trials administered antibiotics at or after cord clamping, or post-operatively, so results may have limited applicability to current practice which generally favours administration prior to skin incision. We have no data on any infant outcomes, nor on late infections (up to 30 days) in the mother; these are important gaps in the evidence that warrant further research. Antimicrobial resistance is very important but more appropriately investigated by other trial designs.

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.

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.

Different classes of antibiotics given to women routinely for preventing infection at caesarean section

BACKGROUND

Caesarean section increases the risk of postpartum infection for women and prophylactic antibiotics have been shown to reduce the incidence; however, there are adverse effects. It is important to identify the most effective class of antibiotics to use and those with the least adverse effects.

OBJECTIVES

To determine, from the best available evidence, the balance of benefits and harms between different classes of antibiotic given prophylactically to women undergoing caesarean section.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 September 2014) and reference lists of retrieved papers.

SELECTION CRITERIA

We included randomised controlled trials comparing different classes of prophylactic antibiotics given to women undergoing caesarean section. We excluded trials that compared drugs with placebo or drugs within a specific class; these are assessed in other Cochrane reviews.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the studies for inclusion, assessed risk of bias and carried out data extraction.

MAIN RESULTS

We included 35 studies of which 31 provided data on 7697 women. For the main comparison between cephalosporins versus penicillins, there were 30 studies of which 27 provided data on 7299 women. There was a lack of good quality data and important outcomes often included only small numbers of women.For the comparison of a single cephalosporin versus a single penicillin (Comparison 1 subgroup 1), we found no significant difference between these classes of antibiotics for our chosen most important seven outcomes namely: maternal sepsis - there were no women with sepsis in the two studies involving 346 women; maternal endometritis (risk ratio (RR) 1.11, 95% confidence interval (CI) 0.81 to 1.52, nine studies, 3130 women, random effects, moderate quality of the evidence); maternal wound infection (RR 0.83, 95% CI 0.38 to 1.81, nine studies, 1497 women, random effects, low quality of the evidence), maternal urinary tract infection (RR 1.48, 95% CI 0.89 to 2.48, seven studies, 1120 women, low quality of the evidence) and maternal composite adverse effects (RR 2.02, 95% CI 0.18 to 21.96, three studies, 1902 women, very low quality of the evidence). None of the included studies looked for infant sepsis nor infant oral thrush.This meant we could only conclude that the current evidence shows no overall difference between the different classes of antibiotics in terms of reducing maternal infections after caesarean sections. However, none of the studies reported on infections diagnosed after the initial postoperative hospital stay. We were unable to assess what impact, if any, the use of different classes of antibiotics might have on bacterial resistance.

AUTHORS' CONCLUSIONS

Based on the best currently available evidence, cephalosporins and penicillins have similar efficacy at caesarean section when considering immediate postoperative infections. We have no data for outcomes on the baby, nor on late infections (up to 30 days) in the mother. Clinicians need to consider bacterial resistance and women's individual circumstances.

A randomized controlled trial comparing two different antibiotic regimens for prophylaxis at cesarean section

OBJECTIVES

To compare the efficacy of intravenous single dose, less costly cefotaxime and more expensive amoxycillin-clavulanic acid combination for prophylaxis at cesarean section.

METHOD

A double blind randomized controlled trial was undertaken on 760 subjects with two parallel treatment groups. Data were analyzed using Graphpad Instat 3 McIntosh software by Student's t test, Mann-Whitney U test, the Chi-squared test or fisher's exact test.

RESULTS

Comparatively narrow spectrum low cost cefotaxime is as effective as more expensive commonly used amoxicillin-clavulanic acid with no significant difference of infectious morbidity and hospital stay (p = 0.27 and 0.11 in elective and emergency cases respectively).

CONCLUSION

Less costly cefotaxime should be preferred compared to more costly amoxicillin-clavulanic acid combination for prophylaxis at cesarean section.