Antibiotic prophylaxis during obstetric and gynaecology surgery in adults: background information

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1 Antibiotic prophylaxis during obstetric and gynaecology surgery in adults: background information Pages 1 to 3 provide available evidence and references to support the surgical prophylaxis recommendations. Pages 4 and 5 contain the guideline recommendations. The aim of antibiotic prophylaxis in surgery is to minimise in the risk of surgical site infection (SSI). For most procedures it is appropriate to use a single pre-operative antibiotic dose (administered within 30minutes of skin incision) to reduce the risk of SSI. This does not apply in caesarean section where antibiotics are currently administered after the umbilical cord has been clamped. Patients at risk of MRSA carriage or known to be carriers of MRSA (click here) will need an alternative prophylaxis agent(s) please contact medical microbiology for advice Abdominal or vaginal hysterectomy (1)(2) Patients undergoing an abdominal or vaginal hysterectomy should receive single dose antibiotic prophylaxis. More than 30 prospective randomised clinical trials and two meta-analyses support the use of prophylactic antibiotics to substantially reduce post-operative infectious morbidity and mortality and decrease length of hospitalisation in women undergoing hysterectomy. Although no trials have been conducted in laparoscopic procedures, antibiotic prophylaxis seems reasonable. Bacterial vaginosis is a known risk factor for surgical site infection after hysterectomy. Preoperative treatment and postoperative treatment of bacterial vaginosis with metronidazole for at least 4 days beginning just before surgery significantly reduces vaginal cuff infection among women with abnormal vaginal flora. Laparoscopy and Laparotomy (2) Laparoscopies and laparotomies do not breach surfaces colonised with bacteria from the vagina, and infections after these procedures more commonly result from contaminating skin bacteria only. No data are available to recommend antibiotic prophylaxis in clean surgery not involving vaginal operations or intestinal operations. Antibiotic prophylaxis is not recommended in patients undergoing diagnostic laparoscopy or exploratory laparotomy. Hysterosalpingogram and hysteroscopy (2) Post-hysterosalpingogram (HSG) PID is an uncommon (1.4%-3.4%) but potentially serious complication in this patient population. Patients with dilated fallopian tubes at the time of HSG have a higher rate of post-hsg PID. The possibility of lower genital tract infection with Chlamydia should be considered before performing this procedure. In a retrospective review, investigators observed no cases of post-hsg PID in patients with non-dilated fallopian tubes (0/398). In patients with no history of pelvic infection, HSG can be performed without prophylactic antibiotics. If HSG demonstrates dilated fallopian tubes then doxycycline 100mg twice daily for 5 days should be given to reduce the incidence of post-hsg PID. Chromotubation at the time of diagnostic laparoscopy is similar to HSG therefore the recommendation for doxycycline is the same. However there is no evidence to support this recommendation. In patients thought to have to have an active pelvic infection, neither HSG nor chromotubation should be performed. A Cochrane review of prophylactic antibiotics for transcervical intrauterine procedures (3) found no published randomized controlled trials that assess prophylactic antibiotics effects on infectious complications following transcervical intrauterine procedures.

2 Infectious complications after hysteroscopy are uncommon. A prospective study of 2,116 surgical hysteroscopies were performed without antibiotic prophylaxis and only 30 (0.85%) cases of endometritis were noted postoperatively. A single prospective study has evaluated the usefulness of amoxicillin and clavulanate antibiotic prophylaxis in preventing bacteraemia associated with hysteroscopic endometrial laser ablation or endometrial resection. Although the incidence of bacteraemia was lower in the antibiotic group than the placebo group (2% verses 16%), most of the microorganisms isolated were of dubious clinical significance (anaerobic staphylococci) and may have resulted from contamination. Post operative infection requiring antibiotics was not significantly different between the groups: 11.4% and 9% of patients required antibiotics in the placebo and antibiotic group respectively. Given the low risk of infection and lack of evidence of efficacy, routine antibiotic prophylaxis is not recommended for the general patient population undergoing these procedures. However as with other transcervical procedures, prophylaxis may be considered in those patients with a history of PID, or tubal damage noted at the time of procedure. Evacuation of retained products of conception (4) The RCOG has published a Green-top guideline on the Management of early pregnancy loss (5) which says that there is insufficient evidence to recommend routine antibiotic prophylaxis prior to surgical uterine evacuation and that antibiotic prophylaxis should be given based on individual clinical indications. A randomised trial of prophylactic doxycycline in curettage for incomplete miscarriage did not demonstrate an obvious benefit but the study was of insufficient power to detect a clinically meaningful change in infectious morbidity. Until further research is available, the authors suggest that antibiotic prophylaxis should only be given based on individual clinical indications. Concerns have been raised about the infective risks of non-surgical management but published data suggest a reduction in clinical pelvic infection and no adverse affects on future fertility. (5) A Cochrane review of Antibiotics for incomplete abortion (6) found that there was not enough evidence to evaluate a policy of routine antibiotic prophylaxis to women with incomplete abortion. The ACOG practice bulletin first considers antibiotic prophylaxis at the time of suction curettage for elective abortion, then goes on to say that: "The risk of infection after suction curettage for missed abortion should be similar to that after suction curettage for elective abortion. Therefore, despite the lack of data, antibiotic prophylaxis should also be considered for these patients" The MIST trial (7) found that the incidence of gynaecological infection after surgical, expectant, and medical management of first trimester miscarriage is low (2-3%), and no evidence exists of a difference by the method of management IUD Insertion (8) Most of the risk of IUD-related infection occurs in the first few weeks to months after insertion, suggesting that contamination of the endometrial cavity at the time of insertion is the mechanism of infection, rather than the IUD itself. A Cochrane Collaboration review (which included four randomised controlled trials) concluded that either doxycycline 200mg or azithromycin 500mg by mouth before IUD insertion confers little benefit. (3) A reduction in unscheduled visits to the provider was marginally significant, but the authors concluded cost effectiveness of routine prophylaxis remains questionable. In the one trial performed in the US, all patients were screened for gonorrhoea and chlamydia and some positive test results were excluded from the study. The cost effectiveness of screening for sexually transmitted diseases before IUD insertion remains unclear because of limited data. However this US study concluded that in patients screened for sexually transmitted infections before IUD insertion, prophylactic antibiotics conferred no benefit. Antibiotic prophylaxis for IUD insertion is not recommended by SIGN. (1) Endometrial biopsy (2) No data available on infectious complications of endometrial biopsy. Incidence is presumed to be negligible. It is recommended that this procedure be performed without the use of antimicrobial prophylaxis. Endocarditis prophylaxis Routine endocarditis prophylaxis is no longer recommended for patients undergoing urological or gynaecological procedures. The National Institute of Clinical Excellence (NICE), having reviewed the evidence, concluded that there was insufficient evidence to support prophylaxis against infective endocarditis for these procedures. (9)

3 Botulinum toxin for urogynaecological procedures Theoretically, the effect of botulinum toxin may be potentiated by aminoglycoside antibiotics or spectinomycin, or other medicinal products that interfere with neuromuscular transmission. (10) A Cochrane review highlighted the promise of intravesical botulinum toxin as a therapy for overactive bladder symptoms, but identified that as yet there is too little controlled trial data that exists on benefits and safety compared with other interventions or with placebo. (11) The theoretical risk of interference of neuromuscular transmission with concurrent gentamicin and botulinum toxin means the combination should be reserved for second line use only in patients reporting anaphylaxis to penicillins. References 1. Scottish Intercollegiate Guideline Network. Antibiotic Prophylaxis in Surgery Guideline 104 (2008) 2. The American College of Obstetricians and Gynaecologists. ACOG Practice Bulletin: Clinical management guidelines for obstetrician-gynaecologists. Obstetrics and Gynaecology (2009). 113(5) Thinkhamrop J, Laopaiboon M, Lumbiganon P. Prophylactic antibiotics for transcervical intrauterine procedures. Cochrane Database of Systematic Reviews (2007) 4. Royal College of Obstetrician and Gynaecologists. Clinical Query Bank. Published 5/7/11. accessed via 5. Royal College of Obstetricians and Gynaecologists. The Care of Women Requesting Induced Abortion. Evidencebased Clinical Guideline Number 7. Nov May W, Gülmezoglu AM, Ba-Thike K. Antibiotics for incomplete abortion. Cochrane Database of Systematic Reviews (2007) 7. J Trinder, P Brocklehurst, R Porter et at. Management of miscarriage: expectant, medical or surgical? Results of randomised controlled trial (miscarriage treatment (MIST) trial). British Medical Journal (2006) 332 (7552): Grimes DA, Lopez LM, Schulz KF. Antibiotic prophylaxis for intrauterine contraceptive device insertion (Review). Cochrane Database of systematic reviews (2010) 9. National Institute of Clinical Excellence (NICE). Clinical Guideline 64. Prophylaxis against infective endocarditis. March Allergan. Botox 100 units. Summary of product characteristics. Accessed via last updated on emc 19/10/ Duthie JB, Herbison GP, Wilson DIain, Wilson D. Botulinum toxin injections for adults with overactive bladder syndrome. Cochrane Database of Systematic Reviews 2007, Issue 3. Art. No.: CD DOI: / CD pub2 (assessed as up to date )

4 Guidelines for Gynaecological Antibiotic Surgical Prophylaxis Type of Surgery PERI-OPERATIVE POST-OPERATIVE Hysterectomy Major gynaecological cancer surgery Urogynaecological procedures including those involving mesh Laparoscopic procedures (operative, diagnostic, tubal sterilisation) Hysterosalpingogram (HSG) Hysteroscopy First line (NOT penicillin allergic) Second line (incl penicillin allergic) Extended prophylaxis A maximum of 24 hours may be considered at consultant request If uterus instrumented & woman of reproductive age or procedure demonstrates dilated fallopian tubes Azithromycin 1g PO STAT Pipelle endometrial biopsy Intra-uterine contraceptive device (IUD) insertion TVT, TOT PLUS Gentamicin 2mg/Kg IV STAT If anaphylaxis with penicillin then: PLUS Gentamicin 2mg/Kg IV STAT Azithromycin 1g PO STAT if risk factors for sexually transmitted infections Cystoscopy Gentamicin 2mg/Kg IV STAT Gentamicin 2mg/Kg IV STAT Urogynaecological procedures involving botox Surgical termination of pregnancy Azithromycin 1g PO STAT PLUS Metronidazole 800mg PO STAT Gentamicin 2mg/Kg IV STAT Concurrent gentamicin with botulinum toxin should be used with caution Medical termination of pregnancy Cervical cerclage discuss with medical microbiology as will depend on stage of pregnancy If anaphylaxis with penicillin then administer gentamicin 2mg/Kg IV STAT and metronidazole 500mg IV STAT

5 Guidelines for Obstetric Antibiotic Surgical Prophylaxis Type of Surgery Caesarean section First line (NOT penicillin allergic) Pre-clamping of the cord PERI-OPERATIVE Second line (incl penicillin allergic) Pre-clamping of the cord Assisted delivery Group B streptococcal (GBS) colonisation in mother Benzylpenicillin 3g IV STAT at start of labour followed by 1.8g 4hrly until delivery See empirical treatment guidelines for more information (link) Clindamycin 900mg IV 8hrly at start of labour until delivery Post-delivery: none POST OPERATIVE Extended prophylaxis Perineal tear (recommended for 3 rd /4 th degree tears involving sphincter/rectal mucosa) Cefuroxime 750mg IV 8hrly PLUS Metronidazole 500mg IV 8hrly Clindamycin 600mg IV 6hrly After 24 hours IV switch to oral: Cefalexin 500mg 8hrly PLUS Metronidazole 400mg 8hrly for 5 days Clindamycin 450mg 6hrly for 5 days Manual removal of placenta Cefuroxime 750mg IV 8hrly PLUS Metronidazole 500mg IV 8hrly Clindamycin 600mg IV 6hrly for 24hours After 24 hours IV switch to oral: Cefalexin 500mg 8hrly PLUS Metronidazole 400mg 8hrly for 6 days Clindamycin 450mg 6hrly for 6 days Medical termination of pregnancy up to 20wks Postpartum RPOC or repeat ERPC Metronidazole 400mg PO 12hrly PLUS Cefalexin 500mg PO 8hrly for 7 days Clindamycin 450mg PO 6hrly for 7days Cooks Balloon Tamponade Cefuroxime 1.5g IV TDS PLUS Metronidazole 500mg IV TDS for duration balloon is in situ Clindamycin 600mg IV 6hrly for duration balloon is in situ