Surgical site infections in a longitudinal cohort of neonatal intensive care unit patients

[Update Perioperative Antibiotic Prophylaxis in Neonatology]

This narrative review discusses basic principles of the perioperative antibiotic prophylaxis (PAP) in premature and at term newborns and refers to some particularities concerning the indication and dosing issues. Although this is a vulnerable patient population, the spectrum of activity should not be unnecessarily broad and the regular PAP must not be prolonged beyond 24 hours.

Complication rates in very low and extremely low birth weight infants following laparotomy: a prospective study

INTRODUCTION

Surgical site occurrences (SSO), including surgical site infection, dehiscence, and incisional hernia, are complications following laparotomy. SSO rates in premature neonates are poorly understood. We hypothesize that SSO rates are higher among extremely low birth weight (ELBW) infants compared to very low birth weight (VLBW) infants and strive to determine the optimal abdominal closure method for these infants.

METHODS

We conducted a prospective observational study of infants < 1.5 kg (kg) undergoing laparotomy at two institutions from 1/1/2020 to 5/1/2022. Patients were grouped by weight and closure; SSO rates were computed and the association tested using Fisher's exact test.

RESULTS

We identified 59 patients and 104 total operations. At initial surgery, 37 patients weighed < 1 kg (ELBW); 22 patients weighed 1-1.5 kg (VLBW). Complication rate for ELBW was 6(16%) vs. 2(9%) in VLBW, but not significant (p = 0.45). More complications followed a single-layer compared to a two-layer closure (18 vs. 2), but not significant (p = 0.30).

CONCLUSIONS

SSO rates are higher for ELBW infants undergoing laparotomy, and fewer complications follow two-layer closure. However, these findings did not reach statistical significance. Further studies are needed to identify modifiable factors to reduce postoperative complications in these infants.

Next Steps for Health Care-Associated Infections in the Neonatal Intensive Care Unit

We discuss the burden of health care-associated infections (HAIs) in the neonatal ICU and the role of quality improvement (QI) in infection prevention and control. We examine specific QI opportunities and approaches to prevent HAIs caused by Staphylococcus aureus , multidrug-resistant gram-negative pathogens, Candida species, and respiratory viruses, and to prevent central line-associated bloodstream infections (CLABSIs) and surgical site infections. We explore the emerging recognition that many hospital-onset bacteremia episodes are not CLABSIs. Finally, we describe the core tenets of QI, including engagement with multidisciplinary teams and families, data transparency, accountability, and the impact of larger collaborative efforts to reduce HAIs.

Optimizing skin antisepsis for neonatal surgery: A quality improvement initiative

PURPOSE

Surgical site infections (SSIs) are a significant determinant of morbidity in the Neonatal Intensive Care Unit (NICU). Chlorhexidine gluconate/isopropyl alcohol (CHG-IPA) skin prep has demonstrated superiority over Povidone-Iodine (PI) in preventing SSIs in adults, however FDA labeling discourages CHG use in infants <2 months. This project aimed to i) create evidence for safe CHG skin antisepsis in neonates; and ii) evaluate the safety and effectiveness of CHG skin prep for neonatal surgery.

METHODS

A literature review was conducted to assess the safety and effectiveness of neonatal CHG skin antisepsis. Following stakeholder engagement, a CHG surgical skin prep protocol and validated neonatal skin integrity tool to assess prep-associated skin injury were implemented in 50 consecutive, eligible neonates ≥1500 g and ≥34 weeks post conceptual age undergoing abdominal or thoracic surgery. SSI rates were compared to a matched, historical PI skin prep cohort.

RESULTS

2%CHG-70%IPA or 0.5%CHG-70%IPA were used based on gestational age cutoffs. None of the CHG patients experienced adverse skin prep outcomes while 8% developed SSIs, compared to 14% in the historical PI cohort.

CONCLUSION

This project engaged NICU stakeholders in quality improvement work and informed the implementation of a safe and effective CHG skin prep protocol for neonatal surgery. LOE: IV.

Prevention of Surgical Site Infections in Neonates and Children: Non-Pharmacological Measures of Prevention

A surgical site infection (SSI) is an infection that occurs in the incision created by an invasive surgical procedure. Although most infections are treatable with antibiotics, SSIs remain a significant cause of morbidity and mortality after surgery and have a significant economic impact on health systems. Preventive measures are essential to decrease the incidence of SSIs and antibiotic abuse, but data in the literature regarding risk factors for SSIs in the pediatric age group are scarce, and current guidelines for the prevention of the risk of developing SSIs are mainly focused on the adult population. This document describes the current knowledge on risk factors for SSIs in neonates and children undergoing surgery and has the purpose of providing guidance to health care professionals for the prevention of SSIs in this population. Our aim is to consider the possible non-pharmacological measures that can be adopted to prevent SSIs. To our knowledge, this is the first study to provide recommendations based on a careful review of the available scientific evidence for the non-pharmacological prevention of SSIs in neonates and children. The specific scenarios developed are intended to guide the healthcare professional in practice to ensure standardized management of the neonatal and pediatric patients, decrease the incidence of SSIs and reduce antibiotic abuse.

A meta-analysis showing the effect of surgical site wound infections and associated risk factors in neonatal surgeries

A meta-analysis was performed to assess the effect of surgical site wound infections and risk factors in neonates undergoing surgery. A systematic literature search up to January 2022 incorporated 17 trials involving 645 neonates who underwent surgery at the beginning of the trial; 198 of them had surgical site wound infections, and 447 were control for neonates. The statistical tools like the dichotomous or continuous method used within a random or fixed-influence model to establish the odds ratio (OR) and mean difference (MD) with 95% confidence intervals (CIs) to evaluate the risk factors and influence of surgical site wound infections in neonates undergoing surgery. Surgical site wound infections had significantly higher mortality with OR value 2.03 at 95% CI 1.40-2.95 with P-value <0.001, the longer length of hospital stay (MD, 31.88; 95% CI, 18.17-45.59, P < 0.001), and lower birthweight of neonates (MD, -0.30; 95% CI, -0.53 to -0.07, P = 0.01) compared with neonates with no surgical site wound infections undergoing surgery. However, no remarkable change was observed with surgical site wound infections in the gestational age at birth of neonates (MD, -0.70; 95% CI, -1.46 to 0.05, P = 0.07), and the preoperative antibiotic prophylaxis (OR, 1.28; 95% CI, 0.57-2.87, P = 0.55) compared with no surgical site wound infections for neonates undergoing surgery. Surgical site wound infections had significantly higher mortality, a longer length of hospital stay, and lower birthweight of neonates. However, they had no statistically significant difference in the gestational age at birth of neonates and the preoperative antibiotic prophylaxis compared with no surgical site wound infections for neonates undergoing surgery. Furthermore, evidence is needed to confirm the outcomes.

Factors associated with neonatal surgical site infection after abdominal surgery

PURPOSE

To assess the risk factors for surgical site infections (SSIs) post-abdominal surgery in neonates.

METHODS

A retrospective, single-center cohort study was conducted using patient data from 2009 to 2018. Patient characteristics and several variables were analyzed to identify independent risk factors for SSI.

RESULTS

SSI occurred in 39/406 procedures (9.6%). Univariate analysis showed that the incidence of SSI was significantly higher in patients who had undergone multiple surgical procedures (P = 0.032), prolonged operations (P = 0.016), long-term hospitalization (P < 0.001), long-term antibiotic administration (P < 0.001), with methicillin-resistant Staphylococcus aureus (MRSA) colonization (P = 0.044), contaminated/dirty wounds (P < 0.001), and American Society of Anesthesiologists physical status of 3 or 4 (P = 0.021). Multivariate analysis identified prolonged operations [odds ratio (OR): 2.91 (1.21-8.01)] and contaminated/dirty wounds [OR: 5.42 (2.41-12.1)] as independent risk factors. Patients with SSI had a higher incidence of MRSA colonization (27.8% vs. 14.8%, P = 0.044), longer antibiotic administration (24 days vs. 8 days, P = 0.049), and longer hospitalization times (98 days vs. 43 days, P = 0.007) than those without SSIs.

CONCLUSIONS

Long operations exceeding 100 min and surgical procedures with contaminated/dirty wounds are independent risk factors for neonatal SSIs after abdominal surgery. SSIs were related to MRSA colonization during hospitalization, long-term antibiotic administration, and long-term hospitalization.

Surgery-Associated Infections among Infants Born Extremely Preterm

OBJECTIVE

To assess the burden of invasive infection following surgery (surgery-associated infections [SAI]) among infants born extremely premature.

STUDY DESIGN

This was an observational, prospective study of infants born at gestational age 22-28 weeks hospitalized for >3 days, between April 1, 2011, to March 31, 2015, in academic centers of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network. SAI was defined by culture-confirmed bacteremia, fungemia, or meningitis ≤14 days following a surgical procedure.

RESULTS

Of 6573 infants, 1154 (18%) who underwent surgery were of lower gestational age (mean [SD]: 25.5 [1.6] vs 26.2 [1.6], P < .001), lower birth weight (803 [220] vs 886 [244], P < .001), and more likely to have a major birth defect (10% vs 3%, P < .001); 64% had 1 surgery (range 1-10 per infant). Most underwent gastrointestinal procedures (873, 76%) followed by central nervous system procedures (150, 13%). Eighty-five (7%) infants had 90 SAIs (78 bacteremia, 5 fungemia, 1 bacteremia and meningitis, 6 meningitis alone). Coagulase-negative staphylococci were isolated in 36 (40%) SAI and were isolated with another organism in 5 episodes. Risk of SAI or death ≤14 days after surgery was greater after gastrointestinal compared with central nervous system procedures (16% vs 7%, adjusted relative risk [95% CI]: 1.95 [1.15-3.29], P = .01). Death ≤14 days after surgery occurred in 141 of the 1154 infants; 128 deaths occurred after gastrointestinal surgeries.

CONCLUSIONS

Surgical procedures were associated with bacteremia, fungemia, or meningitis in 7% of infants. The epidemiology of invasive postoperative infections as described in this report may inform the selection of empiric antimicrobial therapy and postoperative preventive care.

Expanding antimicrobial stewardship strategies for the NICU: Management of surgical site infections, perioperative prophylaxis, and culture negative sepsis

OBJECTIVE

To review antibiotic stewardship strategies for neonatal intensive care units (NICU) in the areas of management of surgical site infections, perioperative prophylaxis and culture negative late onset sepsis.

FINDING

Review of local microbiology, stratification of surgical procedures by risk of contamination of the surgical site, and adherence to evidence-based principles of perioperative antibiotic administration (targeted therapy, effective dosing, appropriate timing and limiting duration post-operatively) can help to minimize unnecessary antibiotic use for neonatal surgery. Creating a late onset sepsis case definition, appropriate collection and interpretation of blood cultures, and instituting antibiotic time-outs can minimize the overuse of antibiotics for culture negative sepsis.

CONCLUSION

Effective implementation of these antimicrobial stewardship strategies in the NICU can reduce unnecessary antimicrobial use and limit the emergence of resistant pathogens.

Role of microbiological tests and biomarkers in antibiotic stewardship

Laboratory tests are critical in the detection and timely treatment of infection. Two categories of tests are commonly used in neonatal sepsis management: those that identify the pathogen and those that detect host response to a potential pathogen. Decision-making around antibiotic choice is related to the performance of tests that directly identify pathogens. Advances in these tests hold the key to progress in antibiotic stewardship. Tests measuring host response, on the other hand, are an indirect marker of potential infection. While an important measure of the patient's clinical state, in the absence of pathogen detection these tests cannot confirm the appropriateness of antibiotic selection. The overall impact these tests then have on antibiotic utilization depends the test's specificity for bacterial infection, clinical scenario where it is being used and the decision-rule it is being integrated into for use. In this review we discuss common and emerging laboratory tests available for assisting management of neonatal infection and specifically focus on the role they play in optimizing antibiotic utilization.

Effects of intraoperative temperatures on postoperative infections in infants and neonates

BACKGROUND

Perioperative hypothermia has been shown to increase surgical site infection (SSI) rates in adults. We sought to characterize whether intraoperative hypothermia or hyperthermia is associated with postoperative infections in infants.

METHODS

We conducted a retrospective review of patients ≤6 months old who underwent surgical procedures from November 2013 to October 2015 at a Level I ACS Children's Surgical Center. The outcome was infections within 30 days after operation, with particular attention to SSI. Data obtained included weight and age at surgery, American Society of Anesthesiologists (ASA) physiologic status, wound class, case length, blood transfusion within 72 h of surgery, and administration of prophylactic antibiotics. Temperatures were classified as hypothermia (T < 36 °C), normothermia (T = 36.0 to 37.9 °C), and hyperthermia (T ≥ 38 °C).

RESULTS

The 885 patients had 25 SSIs (2.8%) and 11 nonsurgical site infections (1.2%). On univariate analysis, weight at surgery, higher ASA, perioperative transfusions, and longer case length were associated with higher rate of SSI. Higher median T_high, higher median T _low, and any hyperthermia were associated with higher rate of SSI. On multivariable logistic regression adjusted analyses, hyperthermia at any time during the case was associated with SSI (OR 3.47, [95% CI 1.34, 9.04], p = 0.011). Transfusions were also associated with higher SSI rates (OR 3.60 [95% CI, 1.28, 10.3], p = 0.016).

CONCLUSIONS

Intraoperative hyperthermia is associated with increased SSI rates in infants.

LEVEL OF EVIDENCE

III.

Risk Factors for Surgical Site Infection in Neonates: A Systematic Review of the Literature and Meta-Analysis

Purpose: Surgical site infections (SSI) contribute to postoperative morbidity and mortality in children. Our aim was to evaluate the prevalence and identify risk factors for SSI in neonates. Methods: Using a defined strategy, three investigators searched articles on neonatal SSI published since 2000. Studies on neonates and/or patients admitted to neonatal intensive care unit following cervical/thoracic/abdominal surgery were included. Risk factors were identified from comparative studies. Meta-analysis was conducted according to PRISMA guidelines using RevMan 5.3. Data are (mean ± SD) prevalence. Results: Systematic review-of 885 abstracts screened, 48 studies (27,760 neonates) were included. The incidence of SSI was 5.6% (1,564 patients). SSI was more frequent in males (61.8%), premature babies (77.4%), and following gastrointestinal surgery (95.4%). Meta-analysis-10 comparative studies (16,442 neonates; 946 SSI 5.7%) showed that predictive factors for SSI development were gestational age, birth weight, age at surgery, length of surgical procedure, number of procedure per patient, length of preoperative hospital stay, and preoperative sepsis. Conversely, preoperative antibiotic use was not significantly associated with development of SSI. Conclusions: Younger neonates and those undergoing abdominal procedures are at higher risk for SSI. Given the lack of evidence-based literature, prospective studies may help determine the risk factors for SSI in neonates.