I. Burden of Surgical Site Infections
Surgical site infections (SSIs) represent a significant portion of health care morbidity and expense in the United States (US). While SSIs complicate 1.9% of all surgeries performed, the incidence of SSI after cesarean delivery (CD) is substantially higher, 7-10%.1-3 As CDs are the most common surgery performed in the US (>1.2 million performed per year), post-CD SSI is a significant cause of increased morbidity, mortality, readmission, and prolonged hospitalization.4 The estimated cost burden for SSI after cesarean delivery is $2852–$3842 per case in the US.5 Recognition and implementation of evidence-based initiatives with a bundle approach to prevent and reduce SSI after CD may aid in optimizing maternal safety, while reducing cost.
II. Classification and Risk Factors of SSI
Surgical site infections include superficial and deep incisional infections as well as organ space infections.1 Incisional infection after CD occurs in 2-7% of cases; necrotizing fasciitis in 0.18%; and endometritis in 2-16%.6 The CDC has released guidelines for the classification and surveillance of SSIs diagnosed within 30 days of surgery.1,7,8
Identification of risk factors for the development of SSIs after CD may help define modifiable points in obstetric care and lower the incidence of SSIs.7 Patient-related risk factors include elevated BMI, diabetes, asthma, smoking, recurrent pregnancy loss, and ASA classification >3.9-11 There is myriad evidence in the general surgical literature that glucose control and smoking cessation decrease rates of surgical site infection.12,13 To our knowledge, impact of these interventions in the pregnant population has not been reported. Pregnancy-specific risk factors include hypertensive disorders, gestational diabetes mellitus, prolonged rupture of membranes, prolonged labor, sexually transmitted infections in pregnancy, chorioamnionitis, and multiple gestations.9-11 Procedure-related risk factors include increased operative time (> 38 min), bowel injury, use of staples, non-closure of subcutaneous tissue if greater than 2 cm, and the inappropriate use of perioperative antibiotics.9-11,14 Emergent CD has been implicated, but has not been directly correlated with increased risk for SSI.
Table 1: Sample SSI Bundle and Phase of Care
|Intervention||Phase of Care|
|4% Chlorhexidine Gluconate shower x 233
night before & morning of surgery
|Hair removal with clippers34
immediately before entering OR
Blood glucose < 126 mg/dl* (Pre-op, Intra-op)17
Blood glucose < 200 mg/dl (Post-Op)8,18
|Pre-Op, Intra-Op, Post-Op|
|Appropriate antibiotic administration within 1 hour of skin incision*21,22
< 120 kg – 2 g Cefazolin
≥ 120 kg – 3 g Cefazolin
500 mg Azithromycin if ruptured membranes
|Maintain normothermia, maternal temp. > 36°C*26||Pre-Op, Intra-Op, Post-Op|
|Chlorhexidine with alcohol skin prep35||Pre-Op|
|Providone Iodine vaginal prep36||Pre-Op|
|Umbilical cord traction for placental delivery37||Intra-Op|
|Antibiotic re-dosing if EBL > 1500 mL or time > 4 hrs23||Intra-Op|
|Glove change prior to fascia closure38||Intra-Op|
|Subcutaneous tissue closure with suture for depth > 2 cm39||Intra-Op|
|Skin closure with suture35||Intra-Op|
|Dressing removal between 24–48 hrs8||Post-Op|
|Patient education on wound care & signs of SSI*32||Post-Op|
|* Indicates where anesthesia professional may have a collaborative role in the interventions.|
III. Developing a SSI Bundle
The Institute for Healthcare Improvement introduced the concept of “bundles” as a way to adopt evidence-based guidelines into practice to improve patient outcomes and care (Figure 1).15 Institutions that have implemented SSI bundles to decrease rates of infection following CD have seen statistically significant decreases in postoperative complications.5,16 Although surgeons dictate most of the interventions to decrease SSI, there are a few important circumstances where the anesthesia professional may intervene. The following section will outline evidence-based bundle components that an anesthesia professional may implement to decrease SSIs. An example bundle containing nursing, surgical, and anesthesia components is shown in Table 1.
Peripartum normoglycemia for women with diabetes is associated with improved fetal and maternal outcomes. Conversely, perioperative hyperglycemia is a noted risk factor for post CD SSI.5,9 Further benefits to maintaining a normal range of maternal glucose (70–126 mg/dL) include lowering the risks of neonatal hypoglycemia and maternal ketoacidosis.17 Women with a diagnosis of diabetes should have a blood sugar evaluated preoperatively. Elevated blood glucose should be treated with insulin. If a patient receives insulin, blood glucose should be re-evaluated within 30–60 minutes of administration.18 If the surgical procedure is >1 hour in duration, a bedside glucose level can be obtained intraoperatively to guide treatment. A blood glucose level should also be obtained in the PACU.19 According to the CDC guidelines, a more liberal yet controlled postoperative glucose target of < 200 mg/dl may decrease morbidity associated with hypoglycemic events and strict glycemic control, while still potentially reducing rates of SSI. However, these data originated from the non-obstetric surgical population, and further studies for post-cesarean delivery patients are warranted.8,18,20
The American College of Obstetricians and Gynecologists (ACOG) guidelines recommend the administration of a first generation cephalosporin within 1 hour prior to incision, dosed according to maternal body weight (cefazolin 2 g IV if <120 kg; cefazolin 3 g IV if ≥120 kg). The previous practice of dosing antibiotics after cord clamping has been shown to increase rates of infection and should be abandoned.21 A recent study suggests that azithromycin 500 mg IV administered prior to incision in non-elective CD, in addition to a cephalosporin, decreased the rate of SSI by half.22 However, further validation with assurance of primary cephalosporin coverage will be important to refine the target population who will most benefit from this adjunct. Patients with anaphylaxis to penicillin can receive clindamycin 900 mg IV and gentamycin 5 mg/kg IV (dosing weight) prior to incision, although local antibiotic resistance patterns may dictate the use of vancomycin or other antibiotics depending on these patterns.21 The re-dosing of prophylactic antibiotics in the setting of postpartum hemorrhage defined as >1500 mL estimated blood loss, and also after two half-lives of the medication have passed, are additional strategies that may reduce post-CD SSIs.23 Further studies are required in the parturient population to definitively validate these redosing recommendations.
Perioperative hypothermia is associated with increased wound infection, length of hospital stay, and increased morbidity and mortality for premature infants.24,25 Maternal temperature should be monitored intraoperatively and postoperatively with a goal perioperative maternal temperature of >36.0 °C per WHO guidelines.26 The anesthesia professional may consider a temporal thermometer or foley temperature probe as the patient is awake. Skin temperature probes can vary from core temperature by 0.5-2 °C and may be used taking this into account.27 The use of forced air warmers and increasing operating room temperature have been shown to decrease rates of perioperative hypothermia in parturients and neonates.28,29 The anesthesia professional may consider setting the OR temperature to 22.5 °C (72 °F) and placing an upper and/or lower body forced air warmer to ensure normothermia is maintained.8 Intraoperative temperature may also be obtained every 15–30 minutes and documented.30
SSI prevention requires adherence to guidelines by surgeons, nurses, and anesthesia professionals as well as participation by patients and their families.31 Patient education surrounding postoperative wound care, appropriate hand hygiene for patient/staff/family, and signs of infection should be delivered preoperatively as well as postoperatively.32 The anesthesia professional may emphasize strict adherence to hand washing and be vigilant about detecting early signs of infection that may occur at any point of their patient interaction, such as fever, tachycardia, vasopressor requirement, or leukocytosis.
Evidence-based interventions that demand a multidisciplinary team approach have proven effective for decreasing the incidence of post-CD SSIs.31 Integrating change in a hospital system, from identifying evidence-based measures that reduce post-CD wound infections to the final step of applying and tracking such measures, works best if a team approach is used integrating obstetrics, anesthesia, nursing, and quality. The ultimate goal of a SSI bundle is to eliminate deviations from standard of care and decrease maternal morbidity and mortality. Further research is required to determine which set of interventions optimize improvement in patient outcomes.
Dr. Seligman is an Assistant Professor and Division Chief of Obstetric Anesthesia in the Department of Anesthesiology and Critical Care Medicine at the University of New Mexico.
Dr. Katz is an Assistant Professor in the Department of Anesthesiology, Perioperative & Pain Medicine at Icahn School of Medicine at Mount Sinai in New York.
Dr. Farber is an Assistant Professor, Obstetric Anesthesia Fellowship Director, and Associate Division Chief of Obstetric Anesthesia in the Department of Anesthesiology, Perioperative & Pain Medicine at Brigham and Women’s Hospital in Massachusetts.
None of the authors have any disclosures.
The information provided is for safety-related educational purposes only, and does not constitute medical or legal advice. Individual or group responses are only commentary, provided for purposes of education or discussion, and are neither statements of advice nor the opinions of APSF. It is not the intention of APSF to provide specific medical or legal advice or to endorse any specific views or recommendations in response to the inquiries posted. In no event shall APSF be responsible or liable, directly or indirectly, for any damage or loss caused or alleged to be caused by or in connection with the reliance on any such information.
- Centers for Disease Control Surgical Site Infection (SSI) Event. 2018. https://www.cdc.gov/nhsn/pdfs/pscmanual/9pscssicurrent.pdf. Accessed March 13, 2018.
- Yokoe DS, Christiansen CL, Johnson R, et al. Epidemiology of and surveillance for postpartum infections. Emerg Infect Dis 2001;7:837–841.
- Conner SN, Verticchio JC, Tuuli MG, et al. Maternal obesity and risk of postcesarean wound complications. Am J Perinatol 2014;31:299–304.
- Curtin SC, Gregory KD, Korst LM, et al. Maternal morbidity for vaginal and cesarean deliveries, according to previous cesarean history: new data from the birth certificate, 2013. Natl Vital Stat Rep2015;64:1–13,
- Kawakita T, Landy HJ. Surgical site infections after cesarean delivery: epidemiology, prevention and treatment. Matern Health Neonatol Perinatol 2017;3:12.
- Olsen MA, Butler AM, Willers DM, et al. Attributable costs of surgical site infection and endometritis after low transverse cesarean delivery. Infect Control Hosp Epidemiol 2010;31:276–282.
- Rubin RH. Surgical wound infection: epidemiology, pathogenesis, diagnosis and management. BMC Infect Dis 2006;6:171.
- Berrios-Torres SI, Umscheid CA, Bratzler DW, et al. Centers for Disease Control and Prevention Guideline for the Prevention of Surgical Site Infection, 2017. JAMA Surgery 2017;152:784–791.
- Moulton LJ, Munoz JL, Lachiewicz M, et al. Surgical site infection after cesarean delivery: incidence and risk factors at a US academic institution. J Matern Fetal Neonatal Med 2017:1–8.
- Krieger Y, Walfisch A, Sheiner E. Surgical site infection following cesarean deliveries: trends and risk factors. J Matern Fetal Neonatal Med 2017;30:8–12.
- Killian CA, Graffunder EM, Vinciguerra TJ, et al. Risk factors for surgical-site infections following cesarean section. Infect Control Hosp Epidemiol 2001;22:613–617.
- Nolan MB, Martin DP, Thompson R, et al. Association between smoking status, preoperative exhaled carbon monoxide levels, and postoperative surgical site infection in patients undergoing elective surgery. JAMA Surgery 2017;152:476–483.
- May AK, Kauffmann RM, Collier BR. The place for glycemic control in the surgical patient. Surgical Infections 2011;12:405–418.
- Opoien HK, Valbo A, Grinde-Andersen A, et al. Post-cesarean surgical site infections according to CDC standards: rates and risk factors. A prospective cohort study. Acta Obstet Gynecol Scand 2007;86:1097–1102.
- Institute for Healthcare Improvement Evidence-Based Care Bundles. 2018. http://www.ihi.org/Topics/Bundles/Pages/default.aspx2018. Accessed March 13, 2018.
- Ng W, Brown A, Alexander D, et al. A multifaceted prevention program to reduce infection after cesarean section: Interventions assessed using an intensive postdischarge surveillance system. Am J Infect Control 2015;43:805–809.
- ACOG Practice Bulletin. Clinical management guidelines for obstetrician-gynecologists. Number 60, March 2005. Pregestational diabetes mellitus. Obstetrics and Gynecology 2005;105:675–685.
- Bratzler DW, Hunt DR. The surgical infection prevention and surgical care improvement projects: national initiatives to improve outcomes for patients having surgery. Clin Infect Dis 2006;43:322–330.
- Duggan EW, Carlson K, Umpierrez GE. Perioperative hyperglycemia management—an Update. Anesthesiology 2017;126:547–560.
- Vriesendorp TM, Morelis QJ, Devries JH, et al. Early postoperative glucose levels are an independent risk factor for infection after peripheral vascular surgery. A retrospective study. Eur J Vasc Endovasc Surg 2004;28:520–525.
- ACOG Practice Bulletin No. 120: Use of prophylactic antibiotics in labor and delivery. Obstetrics and Gynecology 2011;117:1472–1483.
- Tita AT, Szychowski JM, Boggess K, et al. Adjunctive azithromycin prophylaxis for cesarean delivery. The New N Engl J Med 2016;375:1231–1241.
- Fay KE, Yee L. Applying surgical antimicrobial standards in cesarean deliveries. Am J Obstet Gynecol 2018; 218:416.e1-416.e4.
- de Almeida MF, Guinsburg R, Sancho GA, et al. Hypothermia and early neonatal mortality in preterm infants. J Pediatr 2014;164:271–275 e271.
- Ousey K, Edward KL, Lui S, et al. Perioperative, local and systemic warming in surgical site infection: a systematic review and meta-analysis. Journal of Wound Care 2017;26:614–624.
- Allegranzi B, Zayed B, Bischoff P, et al. New WHO recommendations on intraoperative and postoperative measures for surgical site infection prevention: an evidence-based global perspective. The Lancet Infectious Diseases 2016;16:e288–e303.
- Ikeda T, Sessler DI, Marder D, et al. Influence of thermoregulatory vasomotion and ambient temperature variation on the accuracy of core-temperature estimates by cutaneous liquid-crystal thermometers. Anesthesiology 1997;86:603–612.
- Madrid E, Urrutia G, Roque i Figuls M, et al. Active body surface warming systems for preventing complications caused by inadvertent perioperative hypothermia in adults. Cochrane Database Syst Rev2016;4:CD009016.
- Duryea EL, Nelson DB, Wyckoff MH, et al. The impact of ambient operating room temperature on neonatal and maternal hypothermia and associated morbidities: a randomized controlled trial. Am J Obstet Gynecol 2016;214:505.e501–507.
- Standards for basic anesthetic monitoring. Committee of Origin: Standards and Practice Parameters. (Approved by the ASA House of Delegates on October 21, 1986, last amended on October 20, 2010, and last affirmed on October 28, 2016). https://www.asahq.org/~/media/Sites/ASAHQ/Files/Public/Resources/standards-guidelines/standards-for-basic-anesthetic-monitoring.pdf. Accessed April 2018.
- Carter EB, Temming LA, Fowler S, et al. Evidence-Based bundles and cesarean delivery surgical site infections: a systematic review and meta-analysis. Obstetrics and Gynecology 2017;130:735–746.
- Tartari E, Weterings V, Gastmeier P, et al. Patient engagement with surgical site infection prevention: an expert panel perspective. Antimicrob Resist Infect Control 2017;6:45.
- Edmiston CE, Jr., Lee CJ, Krepel CJ, et al. Evidence for a standardized preadmission showering regimen to achieve maximal antiseptic skin surface concentrations of chlorhexidine gluconate, 4%, in surgical patients. JAMA Surgery 2015;150:1027–1033.
- Tanner J, Norrie P, Melen K. Preoperative hair removal to reduce surgical site infection. Cochrane Database Syst Rev 2011;Cd004122.
- Tuuli MG, Liu J, Stout MJ, et al. A Randomized Trial Comparing Skin Antiseptic Agents at Cesarean Delivery. The N Engl J Med 2016;374:647-655.
- Haas DM, Morgan S, Contreras K. Vaginal preparation with antiseptic solution before cesarean section for preventing postoperative infections. Cochrane Database Syst Rev 2014;12:Cd007892.
- Anorlu RI, Maholwana B, Hofmeyr GJ. Methods of delivering the placenta at caesarean section. Cochrane Database Syst Rev 2008;3:Cd004737.
- Reddy B, Scrafford J. Effect of Intra-Operative Glove-Changing During Cesarean on Post-Op Complications: A Randomized Controlled Trial [12OP]. Obstetrics & Gynecology 2017;129:4S–5S.
- Chelmow D, Rodriguez EJ, Sabatini MM. Suture closure of subcutaneous fat and wound disruption after cesarean delivery: a meta-analysis. Obstetrics and Gynecology 2004;103:974–980.