Evaluation of Prophylactic Antibiotic Use for Delayed Sternal Closure After Cardiothoracic Operation

Assessment of the impact of intravenous antibiotics treatment on gut microbiota in patients: Clinical data from pre-and post-cardiac surgery

Background and aims

Surgical site infection is a common complication after surgery. Periprocedural antibiotics are necessary to prescribe for preventing or treating infections. The present study aimed to explore the effect of intravenous antibiotics on gut microbiota and menaquinone biosynthesis in patients, especially in elderly patients undergoing cardiac surgery.

Methods

A total of 388 fecal samples were collected from 154 cardiac surgery patients. The V3-V4 hypervariable region of the bacterial 16S rRNA gene was amplified and sequenced on a MiSeq PE300. The gut microbiota diversity of samples was analyzed in terms of α- and β-diversity at the OTU level. The different groups were classified according to antibiotics in combinations and single antibiotics. PICRUSt2 was used for preliminary prediction of the gut microbiota function for menaquinone biosynthesis.

Results

The intravenously administered antibiotics which are excreted via bile represents the main antibiotics that could disturb the gut microbiota's composition in cardiac surgery patients, especially for elderly patients. The effect of antibiotics on gut microbiota is produced after antibiotics treatments over one week. The recovery of gut microbiota to the state of pre-antibiotics may require over two weeks of antibiotics withdrawal. Sex factor doesn't represent as an influencer in gut microbiota composition. Long-term use of cefoperazone-sulbactam may affect coagulation function.

Conclusions

The composition of the gut microbiota had a significant change post-intravenous antibiotics treatment in cardiac surgery patients. The richness and diversity of gut microbiota are increased in elderly patients.

The Future of Cardiothoracic Surgical Critical Care Medicine as a Medical Science: A Call to Action

Cardiothoracic surgical critical care medicine (CT-CCM) is a medical discipline centered on the perioperative care of diverse groups of patients. With an aging demographic and an increase in burden of chronic diseases the utilization of cardiothoracic surgical critical care units is likely to escalate in the coming decades. Given these projections, it is important to assess the state of cardiothoracic surgical intensive care, to develop goals and objectives for the future, and to identify knowledge gaps in need of scientific inquiry. This two-part review concentrates on CT-CCM as its own subspeciality of critical care and cardiothoracic surgery and provides aspirational goals for its practitioners and scientists. In part one, a list of guiding principles and a call-to-action agenda geared towards growth and promotion of CT-CCM are offered. In part two, an evaluation of selected scientific data is performed, identifying gaps in CT-CCM knowledge, and recommending direction to future scientific endeavors.

Extended systemic antibiotic prophylaxis in ventricular assist device recipients, an infectious disease perspective

OBJECTIVES

To evaluate whether mediastinitis/deep sternal wound infection (Med/DSWI) is more common in ventricular assist device (VAD) with delayed sternal closure (DSC) compared to VAD with primary sternal closure (PSC).

METHODS

A literature search was done over the last four decades for studies that addressed this comparison.

RESULTS

Two studies met our inclusion criteria, and their results are contradictory. The first study compared 184 VAD recipients with PSC to 180 VAD recipients with DSC. There was no difference in VAD-related infections between DSC and PSC (15% vs. 16%, respectively; odds ratio = 0.965, 95% confidence interval [CI] = 0.525-1.635). The second study compared 464 VAD recipients with PSC to 94 VAD recipients with DSC. The rate of surgical site infection was higher in the DSC patients (12.5% vs. 1.4%, respectively; odds ratio = 10.1; 95% CI = 3.8-27.0). DSC was identified as an independent risk factor for postoperative mortality, but no detailed infection information was given.

CONCLUSIONS

There is no clear evidence of the association between DSC, compared to PSC, and Med/DSWI. Therefore, DSC is not an absolute indication for extended systemic antibiotic prophylaxis. The decision to extend the duration of systemic antibiotic prophylaxis should be made on a case-by-case basis, in collaboration with an infectious disease specialist.

The solvent effect modulates the formation of homogeneous polyphenol composite hydrogels with improved transparency and mechanical strength for antibacterial delayed sternal closure films

The usage of delayed sternal closure films after thoracotomy surgery helps doctors deal with emergency conveniently. There is a growing demand to develop suturable, antibacterial and transparent films for delayed sternal closure. Although polyphenol incorporated hydrogels provide good suture ability, they lose transparency because of the heterogeneous distribution of polyphenols during the post-immersion process. Here, a solvent exchange method is proposed to fabricate homogeneous polyphenol composite hydrogels in a bottom-up manner, which utilizes the distinct solvent effect of DMSO and H₂O to modulate the association and disassociation between polyphenols and the polymer backbones on demand. DMSO first provides a protective environment to turn off the intermolecular interactions and allows tannic acid (TA) to be dispersed into the polymer network PEG-lysozyme (PEG-LZM) homogeneously. The following water rehydration turns on the intermolecular interactions between titanic acid and PEG-lysozymes, and results in a homogeneous titanic acid toughened composite hydrogel (PEG-LZM-TA (DH)), which has an improved transparency and mechanical properties than those of the materials prepared by the post-immersion method. In addition, the TA integration provides antibacterial function to the hydrogels. We establish a rabbit delayed sternal closure model to demonstrate that PEG-LZM-TA (DH) films can be sutured to temporarily close the thoracic cavity of rabbits, provide a transparent window to inspect the wound at any time, and control the bacterial contamination efficiently. We further explore the solvent exchange method to other polyphenols and polymeric hydrogel composites. The results suggest that the solvent exchange method provides generic opportunities to fabricate homogeneous polyphenol strengthened hydrogel systems with high performance.

Prevention of Healthcare-associated Infections in Intensive Care Unit Patients

Healthcare-associated infections contribute to morbidity, mortality, and increased cost in intensive care unit patients. Understanding evidence-based prevention strategies can help to optimize patient outcomes.

A Quality Improvement Initiative to Reduce Surgical Site Infections in Patients Undergoing Delayed Sternal Closure After Pediatric Cardiac Surgery

Sternal wound infections (SWI) in delayed sternal closure (DSC) patients are a healthcare burden after congenital heart surgery. There are no guidelines specific for pediatric DSC patients to prevent this costly complication. The hypothesis was that the modifications to a bundled approach for DSC patients would decrease the SWI rate. For this prospective cohort study, DSC patients were postoperatively admitted to a pediatric cardiac care unit from February 2017 to January 2018. Using a modified protocol for prevention of SWI, the infection rates pre- and post-modified protocol were compared. The primary outcome measure was SWI. Secondary outcome measures were compliance with modifications. Retrospective review of cases in pre-protocol modification era from January 1, 2014 to December 31, 2016 showed 377 pediatric cardiopulmonary bypass cases and 39 (10.4%) underwent DSC. During the post-protocol modification era, there were 129 cardiopulmonary bypass cases and 17 (13%) DSC cases. The SWI rate in DSC were 7.7% and 0% for pre-intervention and post-intervention, respectively (p = 0.52). The Bayesian confidence interval with Jeffreys prior gives a 95% confidence interval of 1.5% to 18.3% for pre-intervention and 0 to 13.5% for post-intervention. Compliance with the protocol bundle during the post protocol era was 93-100%. Although preliminary results are not statistically significant due to cohort size, the economic burden and increased LOS for each SWI is clinically significant. The early results of reduced infections for DSC patients using a modified bundle approach appear promising. Continued study and a multicenter project would be beneficial.

Characterization of Postoperative Infection Risk in Cardiac Surgery Patients With Delayed Sternal Closure

OBJECTIVES

To compare the incidence of postoperative infection in cardiac surgery patients who had delayed sternal closure (DSC) with those who had primary sternal closure (PSC) and evaluate the effectiveness of antibiotic prophylaxis in DSC patients.

DESIGN

Retrospective, observational cohort study with propensity score matching.

SETTING

Single academic medical center.

PARTICIPANTS

Cardiothoracic surgery patients, excluding transplantation patients, from a single academic medical center who had DSC or PSC between November 2015 and November 2018.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of 2,685 patients who had cardiac surgery with cardiopulmonary bypass, 99 had DSC. Fifty-nine DSC patients met study inclusion criteria, and the final propensity score matched cohort included 57 patients with DSC and 57 patients with PSC. Propensity score matching reduced bias but was unable to balance all covariates. The most common indication for DSC was coagulopathy in 32 of the 57 patients. All patients in the PSC group received routine antibiotic prophylaxis for 48 hours after surgery. Patients in the DSC group received prolonged broadened prophylaxis until 48 hours after sternal closure. Despite prolonged broadened antibiotic prophylaxis, the DSC group had a higher rate of postoperative infection (31.6% v 3.5%; p < 0.005), mainly pneumonia (19.3% v 1.8%; p < 0.005), in the first 30 days after surgery. There was no difference in the incidence of sepsis (5.3% v 0%; p = 0.24), superficial skin and soft tissue infection (1.8% v 1.8%; p = 1), or mediastinitis/deep tissue infection (5.3% v 0%; p = 0.24) in patients with DSC. Seventy-seven percent of causative organisms for infection were Gram-negative bacteria in the matched cohort.

CONCLUSION

The incidence of postoperative infection, particularly pneumonia, is high in cardiothoracic surgery patients with DSC, even with prolonged broadened antibiotic prophylaxis, but the rate of mediastinitis/deep tissue infection did not appear to be greater with DSC. Additional research is needed into optimal antibiotic prophylaxis in this high-risk group of patients.

Minimization of Surgical Site Infections in Patients With Delayed Sternal Closure After Pediatric Cardiac Surgery

BACKGROUND

Delayed sternal closure (DSC) following pediatric cardiac surgery is commonly implemented at many centers. Infectious complications occur in 18.7% of these patients based on recent multicenter data. We aimed to describe our experience with DSC, hypothesizing that our practices surrounding the implementation and maintenance of the open sternum during DSC minimize the risk of infectious complications.

METHODS

We reviewed patients less than 365 days who underwent DSC between 2012 and 2016 at our institution. Infectious complications as defined by the Society of Thoracic Surgeons Congenital Heart Surgery Database were recorded. Patients with and without infectious complications were compared using Wilcoxon rank sum tests or Fisher exact tests as appropriate.

RESULTS

We identified 165 patients less than 365 days old who underwent DSC, 135 (82%) of whom had their skin closed over their open sternum. Median duration of open sternum was 3 days (range: 1-32 days). Infectious complications occurred in 15 (9.1%) patients-13 developed clinical sepsis with positive blood cultures, one patient developed ventilator-associated pneumonia, and one patient developed wound infection (0.6%). No cases of mediastinitis occurred. No statistical differences in characteristics between patients with and without infectious complications could be identified.

CONCLUSION

Infectious complications after DSC at our institution were notably less than reported in recent literature, primarily due to minimization of surgical site infections. Practices described in the article, including closing skin over the open sternum whenever possible, could potentially aid other institutions aiming to reduce infectious complications associated with DSC.

Antibiotic Prophylaxis for Open Chest Management After Pediatric Cardiac Surgery

OBJECTIVES

Although open chest management optimizes hemodynamics after cardiac surgery, it increases postoperative infections and leads to increased mortality. Despite the importance of antibiotic prophylaxis during open chest management, no specific recommendations exist. We aimed to compare the occurrence rates of bloodstream infection and surgical site infection between the different prophylactic antibiotic regimens for open chest management after pediatric cardiac surgery.

DESIGN

Retrospective, single-center, observational study.

SETTING

PICU at a tertiary children's hospital.

PATIENTS

Consecutive patients younger than or equal to 18 years old with open chest management after cardiac surgery followed by delayed sternal closure, between January 2012 and June 2018.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

We compared the composite occurrence rate of postoperative bloodstream infection and surgical site infection within 30 days after cardiac surgery between three prophylactic antibiotic regimens: 1) cefazolin, 2) cefazolin + vancomycin, and 3) vancomycin + meropenem. In 63 pediatric cardiac surgeries with open chest management, 17 bloodstream infections, and 12 surgical site infections were identified postoperatively. The composite occurrence rates of bloodstream infection and surgical site infection were 10 of 15 (67%), 10 of 19 (53%), and nine of 29 (31%) in the cefazolin, cefazolin + vancomycin, and vancomycin + meropenem regimens, respectively (p = 0.07). After adjusting for age, open chest management duration, extracorporeal membrane oxygenation use, and nasal methicillin-resistant Staphylococcus aureus colonization in multivariable analysis, there was no significant difference between the cefazolin and the cefazolin + vancomycin regimens (p = 0.19), while the vancomycin + meropenem regimen had a lower occurrence rate of bloodstream infection and surgical site infection than the cefazolin regimen (odds ratio, 0.0885; 95% CI, 0.0176-0.446; p = 0.003).

CONCLUSIONS

In this study, a lower occurrence rate of postoperative bloodstream infection and surgical site infection was observed among patients with broad-spectrum antibiotic regimen after pediatric cardiac surgery with open chest management. Further studies, ideally randomized controlled studies investigating the efficacy of broad-spectrum antibiotics and their complications, are warranted before routine implementation of broad-spectrum prophylactic antibiotic regimen.

Antibiotic Management for Delayed Sternal Closure Following Pediatric Cardiac Surgery: A Systematic Review of Recent Literature

Delayed sternal closure after pediatric cardiac surgery is a management option for the treatment of patients with severely impaired heart function. The optimal antimicrobial treatment strategy for this condition is unknown. The aim of this systematic review was to evaluate the current antibiotic administration attitudes in pediatric cardiac surgery patients needing an open chest in terms of infection with a focus on surgical site infection rate. The authors performed a systematic review and meta-analysis of all articles, which described the antibiotic administration strategy and surgical site infection rate in pediatric patients with an open chest after cardiac surgery. The authors performed a subgroup analysis on "standard" versus "non-standard" (defined as any antimicrobial drugs different from the adult guidelines recommendations) therapy for one-proportion meta-analysis with a random effect model. The authors identified 12 studies published from January 1, 2000 to July 1, 2019 including a total of 2,203 patients requiring an open chest after cardiac surgery, 350 of whom (15.9%) developed infections and 182 (8.3%) developed a surgical site infection. The surgical site infection rate in patients with "non-standard" strategy was higher than in patients with "standard" strategy: 8.8% (140 reported infections/1,582 patients) versus 6.8% (42 reported infections/621 patients), p = 0.001. The "standard" antibiotic management proposed by guidelines for adult cardiac surgery patients could be used an acceptable strategy to treat pediatric patients with an open chest after cardiac surgery.