Prophylactic use of antibiotics for nonlaboring patients undergoing cesarean delivery with intact membranes: a meta-analysis

Perioperative antibiotic prophylaxis for nonlaboring cesarean delivery

OBJECTIVE

To estimate the efficacy of antibiotic prophylaxis at the time of nonlaboring cesarean delivery in reducing postpartum infection-related complications.

METHODS

We performed a secondary analysis of an observational study of cesarean deliveries performed at 13 centers from 1999-2000. Patients were included if they had cesarean delivery before labor, did not have intrapartum infection, and were not given antibiotics at delivery for reasons other than prophylaxis. The occurrence of postpartum endometritis, wound infection, and other, less common infection-related complications was compared between those who did and did not receive antibiotic prophylaxis. Results were adjusted for smoking, payer status, gestational age and body mass index at delivery, race, diabetes, antepartum infections, presence of anemia, operative time, type of cesarean delivery (primary or repeat), and center.

RESULTS

Of the 9,432 women who met study criteria, the 6,006 (64%) who received antibiotic prophylaxis were younger, heavier at delivery, and were more likely to be African American, receive public insurance, and have diabetes. Patients who received antibiotic prophylaxis were less likely to develop postpartum endometritis (121 [2.0%] compared with 88 [2.6%], adjusted odds ratio [OR] 0.40, 95% confidence interval [CI] 0.28-0.59) or wound infection (31 [0.52%] compared with 33 [0.96%], adjusted OR 0.49, 95% CI 0.28-0.86).

CONCLUSION

Antibiotic prophylaxis at the time of nonlaboring cesarean delivery significantly reduces the risks of postpartum endometritis and wound infection.

LEVEL OF EVIDENCE

III.

[Single dose of antibiotic prophylaxis in elective cesarean sections]

INTRODUCTION

The aim of our study was to determine whether a single-dose preoperative administration of antibiotics was sufficient to prevent intra and postoperative infections in the parturients without a high risk of developing an infection, in whom the delivery was completed by cesarean section, as well as to answer whether the administered dose of antibiotics satisfied the requirements of therapeutic concentrations necessary to protect against infection in the period during the surgical procedure and during the first 6 postoperative hours.

MATERIAL AND METHODS

All investigated pregnant women were planned to have elective cesarean section as a mode of delivery. They were distributed in groups depending on the type (cephalexin, gentamycin and cephazolin) of antibiotic prophylaxis administered as a single dose. In all patients the clinical postoperative course was followed for possible infection. The concentrations of antibiotics were estimated immediately and 6 h following the operation. The estimation of antibiotic concentrations was done by the method of liquid chromatography (for antibiotics belonging to the group of cephalosporins), i.e. RIA method for antibiotics from the group of aminoglycosides.

RESULTS AND CONCLUSION

The total number of infections in investigated groups was 5.18%. The measured mean concentrations of administered antibiotics following the operation and 6 h later were above MIC. This is a proof that the obtained antibiotic prophylaxis by a single dose administration of anbtibiotic is sufficient to prevent the invasion of pathogenic microorganisms from the skin.

Emerging concepts in antibiotic prophylaxis for cesarean delivery: a systematic review

OBJECTIVE

To review the current status of antibiotic prophylaxis for cesarean delivery, emerging strategies to enhance the effectiveness of antibiotic prophylaxis in reducing postcesarean infection, and the implications of the emerging practices.

DATA SOURCES

We conducted a full PubMed (January 1966 to July 2008) search using the key words "cesarean" and "antibiotic prophylaxis." A total of 277 articles were identified and supplemented by a bibliographic search.

METHODS OF STUDY SELECTION

We selected a total of 15 studies, which included all published clinical trials, meta-analyses of clinical trials, and observational studies evaluating either the timing of antibiotics or the use of extended-spectrum prophylaxis. We also reviewed nine reports involving national recommendations or technical reviews supporting current standards for antibiotic prophylaxis.

TABULATION, INTEGRATION, AND RESULTS

We conducted an analytic review and tabulation of selected studies without further meta-analysis. Although current guidelines for antibiotic prophylaxis recommend the administration of narrow-spectrum antibiotics (cefazolin) after clamping of the umbilical cord, the data suggest that antibiotic administration before surgical incision or the use of extended-spectrum regimens (involving azithromycin or metronidazole) after cord clamp may reduce postcesarean maternal infection by up to 50%. However, these two strategies have not been compared with each other. In addition, their effect on neonatal infection or infection with resistant organisms warrants further study.

CONCLUSION

The use of either cefazolin alone before surgical incision or an extended-spectrum regimen after cord clamp seems to be associated with a reduction in postcesarean maternal infection. Confirmatory studies focusing additionally on neonatal outcomes and the effect on resistant organisms, as well as studies comparing both strategies, are needed.

When should we perform prophylactic antibiotics in elective cesarean cases?

OBJECTIVE

The aim of this study was to determine whether the timing of prophylactic antibiotics at cesarean delivery influences maternal and neonatal infectious morbidity.

STUDY DESIGN

This was a prospective, randomized trial. Four hundred patients that underwent elective cesarean section between June and December 2007 formed the study population. Eleven patients were excluded from the study because they needed transfusion during the cesarean section. The population was divided into two groups: Group A, antibiotic prophylaxis was applied to 194 women before skin incision and Group B, antibiotic prophylaxis was applied to 195 women after umbilical cord clamping. The occurrence of endomyometritis/endometritis, wound infection, febrile morbidity, total infectious morbidity, and neonatal complications were compared.

RESULTS

There were 389 patients enrolled. No demographic differences were observed between groups. No significant difference was found between the groups for total infectious morbidity [relative risk (RR) 1.39, 95% confidence interval (CI) 0.71-2.69] and endometritis (RR 1.40, 95% CI 0.43-4.51). There was no increase in neonatal sepsis (RR 1.47, 95% CI 0.61-3.53), sepsis workup (RR 1.35, 95% CI 0.75-2.42), need for neonatal intensive care (RR 1.77, 95% CI 0.51-6.16), and intensive care stay period (P = 0.16).

CONCLUSIONS

Time of antibiotic prophylaxis application does not change maternal infectious morbidity in cesarean section deliveries. Preoperative prophylaxis application does not affect neonate morbidity rates as stated in literature.

Timing of perioperative antibiotics for cesarean delivery: a metaanalysis

OBJECTIVE

The purpose of this study was to summarize the available evidence on timing of perioperative antibiotics for cesarean delivery.

STUDY DESIGN

We searched the literature for studies that compare prophylactic antibiotics for cesarean delivery that are given before the procedure vs at cord clamping. Only randomized controlled trials were included.

RESULTS

Preoperative administration significantly reduced the risk of postpartum endometritis (relative risk [RR], 0.47; 95% CI, 0.26-0.85; P = .012) and total infectious morbidity (RR, 0.50; 95% CI, 0.33-0.78; P = .002). There was a trend toward lower risk of wound infection (RR, 0.60; 95% CI, 0.30-1.21; P = .15). Preoperative administration of antibiotics did not significantly affect suspected neonatal sepsis that requires a workup (RR, 1; 95% CI, 0.70-1.42), proven sepsis (RR, 0.93; 95% CI, 0.45-1.96), or neonatal intensive care unit admissions (RR, 1.07 95% CI, 0.51-2.24). There was no significant heterogeneity between the randomized controlled trials.

CONCLUSION

There is strong evidence that antibiotic prophylaxis for cesarean delivery that is given before skin incision, rather than after cord clamping, decreases the incidence of postpartum endometritis and total infectious morbidities, without affecting neonatal outcomes.

Successful control program to implement the appropriate antibiotic prophylaxis for Cesarean section

OBJECTIVE

Describe implementation of a successful program to reduce doses (cefazolin 2 to 1 g) used for antimicrobial prophylaxis.

METHODS

Evaluation of an intervention program to reduce prophylactic antimicrobial doses. The intervention included weekly staff discussions, automatic dispensation of 1g-vial of cefazolin by the pharmacy unless expressly requested by surgeon and increase in post-discharge surveillance as a strategy to reassure surgeons of the safety of the reduction. In the pre and post intervention periods, a prospective study of antimicrobial consumption and surgical site infections were measured.

RESULTS

There were 5,164 and 5,204 deliveries in 2001-2002 and 2003-2004, respectively; 1,524 (29.5%) and 1,363 (26%) were cesarean sections. There was a 45% decrease in cefazolin vials used on average per cesarean section (2.29 to 1.25). Patients evaluated increased from 16% to 67% and the SSI rates in both periods were 3.34% to 2.42%, respectively.

CONCLUSION

An ample intervention, including administrative and educational measures, led to high compliance with dose reduction and saved more than US$4,000 in cefazolin, considered important because government reimbursement in Brazil for cesarean section is $80.

Prophylactic antibiotics for transcervical intrauterine procedures

BACKGROUND

The transcervical intrauterine route is commonly used for operative gynecological procedures in women. The vagina is an area of the body that is abundant with normal bacterial flora. An operative procedure through the vagina may, therefore, be considered to have added potential for resulting in post-procedure infection. Prophylactic antibiotics may play a role in the prevention of post-procedure transcervical intrauterine infections.

OBJECTIVES

To assess the effectiveness and safety of antibiotic prophylaxis compared to placebo or no treatment in women undergoing transcervical intrauterine procedures.

SEARCH STRATEGY

The search strategy was based on the Menstrual Disorders and Subfertility Group's search strategy. The following databases were searched:Menstrual Disorders and Subfertility Group Specialized Register;Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library 2006, Issue 4;MEDLINE (1966 to November 2006);EMBASE (1966 to November 2006);Biological Abstracts (1966 to October 2006);AMED (1966 to November 2006). Key words were prepared, in consultation with the Trials Search Coordinator, according to the terms related to our objective: antibiotic, antibiotics, prophylaxis, transvaginal, transcervical intrauterine, endometrial sample, endometrium sampling, endometrial biopsy, hysterosalpingography, hysteroscope, hysteroscopy, hysteroscopic surgery, endometrial ablation, and endometrial resection.

SELECTION CRITERIA

The review authors planned to include only truly randomized controlled trials that compared antibiotic prophylaxis with placebo or no treatment in order to prevent infectious complications after transcervical intrauterine procedures. Controlled clinical trials without randomization and pseudo-randomized trial were excluded.

DATA COLLECTION AND ANALYSIS

No data collection or analysis was done because no trials were eligible for inclusion in the review.

MAIN RESULTS

The search did not identify any randomized controlled trials investigating the effect of antibiotic prophylaxis compared to placebo or no treatment in women undergoing transcervical intrauterine procedures.

AUTHORS' CONCLUSIONS

At this time, there are no published randomized controlled trials that assess prophylactic antibiotics effects on infectious complications following transcervical intrauterine procedures. It is, therefore, not possible to draw any conclusions regarding the use of prophylactic antibiotics for the prevention of post-procedure transcervical intrauterine infections.

Administration of cefazolin prior to skin incision is superior to cefazolin at cord clamping in preventing postcesarean infectious morbidity: a randomized, controlled trial

OBJECTIVE

The objective of the study was to determine whether the administration of cefazolin prior to skin incision was superior to administration at the time of umbilical cord clamping for the prevention of postcesarean infectious morbidity.

STUDY DESIGN

This was a prospective, randomized, double-blind, placebo-controlled trial. Study subjects received cefazolin 15-60 minutes prior to incision and controls received cefazolin at the time of cord clamping. The occurrence of endomyometritis, wound infection, total infectious morbidity, and neonatal complications were compared.

RESULTS

There were 357 subjects enrolled. No demographic differences were observed between groups. There were decreased total infectious morbidity in the study group (relative risk [RR] = 0.4, 95% confidence interval [CI] 0.18 to 0.87), decreased endometritis (RR = 0.2, 95% CI 0.15 to 0.94). No increase in neonatal sepsis (P = .99), sepsis workups (P = .96), or length of stay (P = .17) was observed.

CONCLUSION

Administration of prophylactic cefazolin prior to skin incision resulted in a decrease in both endomyometritis and total postcesarean infectious morbidity, compared with administration at the time of cord clamping. This dosing did not result in increased neonatal septic workups or complications.

Revisões sistemáticas de antibioticoprofilaxia em cesarianas

O objetivo do trabalho foi analisar a evidência científica disponível sobre os efeitos da antibioticoprofilaxia em cesarianas. As presentes revisões sistemáticas compreenderam um exame detalhado da qualidade do desenho e da execução assim como da heterogeneidade clínica entre os ensaios. A meta-análise dos ensaios placebo-controlados (27 estudos) apontou eficácia aproximada de 65% para ambos os desfechos estudados, endometrite e infecção da ferida cirúrgica (IFC), correspondendo a uma queda da incidência de 11% e 5%, respectivamente. As análises de sensibilidade mostraram efeitos sumários semelhantes aos observados para o conjunto dos ensaios. O subgrupo dos 12 ensaios de cesáreas não eletivas indicou benefício importante da antibioticoprofilaxia para ambos os desfechos, correspondente a uma queda de 14% (endometrite) e 5% (IFC). Para cesáreas eletivas (dois ensaios), não foi mostrado benefício relevante. A evidência obtida dos ensaios comparativos de doses foi limitada devido a falhas metodológicas importantes e ao pequeno número de pacientes envolvidas (três ensaios). Os ensaios comparativos de antimicrobianos (sete estudos) não evidenciaram diferença de eficácia entre os dois esquemas analisados, cefalosporinas de 1ª e de 2ª geração.

Surgical site infection following elective Caesarian section: a case-control study of postdischarge surveillance

OBJECTIVES

To ascertain the incidence of postoperative surgical site infection (SSI) following elective Caesarean section (CS) and to compare demographic characteristics and antibiotic administration between infected cases and noninfected control subjects.

METHODS

We conducted a retrospective case-control study of patients undergoing elective CS between 1996 and 2002 at a tertiary centre. Infection-control personnel attempted to contact by telephone all women who had had Caesarean sections, 1 month after their surgery. The women they reached were asked to complete a questionnaire based on CDC-validated criteria for infection to determine whether SSI had occurred. Control subjects without SSI were matched on the basis of having had an elective CS and by date of surgery. We then reviewed the hospital records of both groups.

RESULTS

Over the study period, 1250 elective Caesarean sections were performed and 124 infected cases were identified, giving an overall SSI incidence of 9.9%. Of the 342 women reviewed (124 cases, 218 control subjects), 23% received prophylactic intraoperative antibiotics. Cases and control subjects differed significantly in terms of estimated blood loss, with fewer control subjects having excessive blood loss (P = 0.04). Among those women receiving postoperative antibiotics, case subjects received a significantly higher number of doses than did control subjects (P = 0.003). The groups did not differ significantly in terms of overall antibiotic administration or other demographic variables.

CONCLUSIONS

The incidence of SSI following elective CS according to postdischarge surveillance was 9.9%, which is higher than expected for a low-risk procedure. Because follow-up was not possible for all cases, this incidence may be an underestimate. Underuse of antimicrobial prophylaxis may also be a contributing factor, because prophylactic antibiotics were administered in less than 25% of cases.

Prophylactic antibiotics for non-laboring patients with intact membranes undergoing cesarean delivery: an economic analysis

OBJECTIVE

We conducted an economic analysis of prophylactic antibiotic administration for elective cesarean delivery.

STUDY DESIGN

We created a decision tree comparing the use of prophylactic antibiotics (cefazolin 1 gm intravenous) with no antibiotic use. We modeled the potential for anaphylaxis, and included outcomes of fever and endometritis. Outcome probabilities and effectiveness of antibiotic administration were derived from published sources. Costs are 2001 estimates derived from our hospital's accounting system. Sensitivity analyses were performed over the range of actual patient costs and 95% CI of the risk and probability estimates.

RESULTS

Cost of an uncomplicated elective cesarean delivery was $1638.57. Fever evaluation added $125.91. Elective procedure complicated by endometritis cost $2327.29. Cefazolin administration cost $1.01. The following estimates were used: relative risk (RR) of endometritis with antibiotics was 0.18 (95% CI 0.07-0.45), fever 0.47 (95% CI 0.32-0.68), risk of endometritis without prophylaxis 4.8% (95% CI 0.9%-43%), and fever without prophylaxis 14.4% (95% CI 4%-33%). Cost of an average case without prophylaxis was $1683.72; prophylaxis reduced this to $1653.06. Sensitivity analysis over the ranges above still yielded cost savings.

CONCLUSION

Administration of prophylactic antibiotics for elective cesarean delivery reduced costs by $30.66 per case, approximately 2% of the total cost. Prophylactic antibiotic administration results in cost savings for elective cesarean delivery.

Perioperative antibiotics and practice

Perioperative antibiotic administration and anesthetic practice have major impacts on infectious complications. Anesthesiologists need to place high importance on perioperative antibiotic administration to allow patients to receive optimal benefit from this therapy and to minimize risk. Many aspects of perioperative care ranging from thermoregulation to glycemic control may have profound longterm affects on infection rate and thereby patient outcome.

Suture closure of subcutaneous fat and wound disruption after cesarean delivery: a meta-analysis

OBJECTIVE

To define the role of suture closure of the subcutaneous dead space in preventing wound complications after cesarean delivery.

DATA SOURCES

We searched MEDLINE, the Cochrane Database of Systematic Reviews, and the bibliographies of major texts and review articles.

METHODS OF STUDY SELECTION

Only studies in which patients undergoing cesarean delivery were randomly assigned to closure of the subcutaneous space or to no closure were included. Each study was required to report on at least 1 of the following outcomes: wound infection, hematoma, seroma, or separation. The studies also reported "wound disruption," a combination of these outcomes which either explicitly stated or strongly implied the need for further wound care. Six studies meeting criteria were identified.

TABULATION, INTEGRATION, AND RESULTS

Three studies included 875 patients with any subcutaneous thickness and noted a decrease in wound disruption with closure (relative risk [RR] 0.56; 95% confidence interval [CI] 0.36, 0.86). Two studies reported results from 181 patients with incision depth of 2 cm or less and noted no difference (RR 1.01; 95% CI 0.46, 2.20). Five studies reported results on 887 patients with wound thickness greater than 2 cm. Although only 1 study had a significant effect by itself, when results were combined, there was a significant decrease in wound disruption (RR 0.66; 95% CI 0.48, 0.91). This reduction seems to be largely a result of decreased wound seromas (4 studies, 852 patients, RR 0.42; 95% CI 0.24, 0.75). In women with wound thickness greater than 2 cm, subcutaneous closure resulted in a risk reduction of 6.2%, and 16.2 women would need subcutaneous closure to prevent 1 wound disruption (number needed to treat).

CONCLUSION

Suture closure of subcutaneous fat during cesarean delivery results in a 34% decrease in risk of wound disruption in women with fat thickness greater than 2 cm.

Higher rates of post-partum complications in HIV-infected than in uninfected women irrespective of mode of delivery

OBJECTIVE

To inform the debate on the use of elective caesarean section (CS) delivery in HIV-infected women, we investigated the occurrence of clinical events in the immediate post-partum period in women delivering in 13 European centres.

DESIGN

Two separate matched case-control studies (vaginal and elective CS deliveries) among infected women (cases) and uninfected controls delivering between 1992 and 2002.

METHODS

The prevalence of minor and major post-partum complications was assessed overall for infected and uninfected women; within mode of delivery group (vaginal/CS) the complication rates of infected cases were compared with uninfected controls in a matched analysis.

RESULTS

Overall complication rates were 29.2% (119 of 408) for HIV-infected women, 19.4% (79 of 408) for uninfected women, 42.7% (135 of 316) for CS deliveries and 12.6% (63 of 500) for vaginal deliveries. There were no major complications in women delivering vaginally; but, compared with controls, HIV-infected cases were at increased risk of puerperal fever [odds ratio (OR), 4.5; 95% confidence interval (CI), 1.55-13.07), especially after medio-lateral episiotomy. In the CS group, there were six major complications (five among cases, one control) (OR, 5.1; 95% CI, 0.58-45) and cases had an increased risk of minor complications (OR, 1.51; 95% CI, 1.22-2.41) compared with controls, mainly anaemia not requiring blood transfusion.

CONCLUSION

HIV-infected pregnant women are at increased risk of post-partum complications regardless of mode of delivery, but modification of clinical practice, particularly use of prophylactic antibiotics, would reduce this risk. Infected women should be informed about risks of vertical transmission and post-partum complications, and be involved in mode of delivery decisions.

Antimicrobial prophylaxis in the surgical patient

The primary prophylactic measure against postoperative infection is antiseptic technique in patient preparation, during surgery, and in postoperative patient care. Antimicrobial prophylaxis against postoperative infection is not indicated for procedures with a low infection rate because the expected benefit of antimicrobial treatment is less than the risk of an adverse medication reaction. Antimicrobial prophylaxis has been demonstrated to be of greater benefit than risk in some procedures with higher infection rates; however, because the problem is complex and the data are limited, extra-polating these findings to the practitioner's setting and the individual patient remains a challenge (Table 1). Although antimicrobial prophylaxis for bacterial endocarditis is not effective for most patients, the seriousness of the potential infection has driven the creation of guidelines recommending prophylaxis for at-risk patients undergoing at-risk procedures. Applying these guidelines appropriately could help to reduce unwarranted use of antimicrobials. In the prophylactic use of antimicrobials, as in many medical interventions, the difficulty is balancing the risks of the intervention with the potential benefits. Although we do not have either the randomized, controlled trials or the detailed, patient-specific information to estimate this balance precisely, there are general guidelines to help the clinician choose treatment for most patients.

Severe obstetric morbidity

Obstetric morbidity is an important marker of the quality of obstetric care. This review explores the definition, incidence and significance of obstetric morbidity. Some topical issues related to obstetric morbidity are discussed. In addition, the importance of long-term morbidity and violence against women is highlighted.

Antibiotic prophylaxis for cesarean section

BACKGROUND

The single most important risk factor for postpartum maternal infection is Cesarean delivery.

OBJECTIVES

The objective of this review was to assess the effects of prophylactic antibiotic treatment on infectious complications in women undergoing Cesarean delivery.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group trials register and the Cochrane Controlled Trials Register.

SELECTION CRITERIA

Randomised trials comparing antibiotic prophylaxis or no treatment for both elective and non-elective Cesarean section.

DATA COLLECTION AND ANALYSIS

Two reviewers assessed trial quality and extracted data.

MAIN RESULTS

Sixty-six trials were included. Use of prophylactic antibiotics in women undergoing Cesarean section substantially reduced the incidence of episodes of fever, endometritis, wound infection, urinary tract infection and serious infection after Cesarean section. The reduction in the risk of endometritis with antibiotics was similar across different patient groups. The relative risk for elective Cesarean section was 0.24, 95% confidence interval 0.11 to 0.48. The relative risk for non-elective Cesarean section was 0.30, 95% confidence interval 0.25 to 0.35. The relative risk for undefined or all patients together was 0.29, 95% confidence interval 0.26 to 0.33. Despite the large number of trials, different populations and different antibiotic regimens, there was no statistically significant heterogeneity.

REVIEWER'S CONCLUSIONS

The reduction of endometritis by two thirds to three quarters justifies a policy of administering prophylactic antibiotics to women undergoing elective or non-elective Cesarean section.