Intraoperative wound contamination during abdominal hysterectomy

Effectiveness of reducing bacterial air contamination when covering sterile goods in the operating room setting: a systematic review and meta-analysis

BACKGROUND

Postoperative surgical site infection is a serious problem. Coverage of sterile goods may be important to protect the goods from bacterial air contamination while awaiting surgery.

AIM

To evaluate the effectiveness of this practice in a systematic review covering five databases using search terms related to bacterial contamination in the operating room and on surgical instruments.

METHODS

MEDLINE, Cochrane, CINAHL, Embase, and Web of Science databases were searched from inception to February 13th, 2023, for randomized and non-randomized controlled studies of covering interventions conducted in the operating room setting. The outcome was bacterial air contamination measured as colony-forming units, and a meta-analysis was performed in separate time periods of coverage. This systematic review and meta-analysis is reported according to the PRISMA statement, and the protocol was prospectively registered in PROSPERO (CRD42022323113). The time points ranged from 30 min to 24 h.

FINDINGS

The results showed that covering sterile goods significantly prevented bacterial air contamination as compared to uncovered goods. The meta-analysis was in favour of covering sterile goods for protection from bacterial air contamination, and showed an effect size Z of 4.76 (P<0.00001; confidence interval: -1.94 to -0.81). The heterogeneity analysis showed a heterogeneity of 83%.

CONCLUSION

No negative effects regarding bacterial contamination were found, and so we conclude that protection with a sterile cover decreases bacterial air contamination of sterile goods while waiting for surgery to start.

Bacterial Skin and Soft Tissue Infections in Older Adults

This article focuses on bacterial infections that commonly affect geriatric patients. The elderly population is at a higher risk of contracting bacterial infections due to weakened immune systems and comorbidities. The article explores the cause, pathogenesis, clinical manifestations, and treatment options of these infections. Additionally, antibiotic resistance is a growing concern in the treatment of bacterial infections. The article highlights the importance of preventing these infections through proper hygiene and wound care. This article aims to provide an understanding of bacterial infections in geriatric patients and inform health-care providers on the most effective ways to manage and prevent these infections.

Time-dependent bacterial air contamination of sterile fields in a controlled operating room environment: an experimental intervention study

BACKGROUND

Surgical site infections are a global patient safety concern. Due to lack of evidence on contamination, pre-set surgical goods are sometimes disposed of or re-sterilized, thus increasing costs, resource use, and environmental effects.

AIM

To investigate time-dependent bacterial air contamination of covered and uncovered sterile goods in the operating room.

METHODS

Blood agar plates (N = 1584) were used to detect bacterial air contamination of sterile fields on 48 occasions. Each time, three aerobe and three anaerobe plates were used as baseline to model the preparation time, and 60 (30 aerobe, 30 anaerobe) were used to model the time pending before operation; half of these were covered with sterile drapes and half remained uncovered. Plates were collected after 4, 8, 12, 16, and 24 h.

FINDINGS

Mean time before contamination was 2.8 h (95% confidence interval: 2.1-3.4) in the uncovered group and 3.8 h (3.2-4.4) in the covered group (P = 0.005). The uncovered group had 98 colony-forming units (cfu) versus 20 in the covered group (P = 0.0001). Sixteen different micro-organisms were isolated, the most common being Cutibacterium acnes followed by Micrococcus luteus. Of 32 Staphylococcus cfu, 14 were antibiotic resistant, including one multidrug-resistant Staphylococcus epidermidis.

CONCLUSION

Protecting sterile fields from bacterial air contamination with sterile covers enhances the durability of sterile goods up to 24 h. Prolonged durability of sterile goods might benefit patient safety, since surgical sterile material could be prepared in advance for acute surgery, thereby enhancing quality of care and reducing both climate impact and costs.

Surgical Site Infections: An Update

Surgical site infections (SSIs) lead to adverse patient outcomes, including prolonged hospitalization and death. Wound contamination occurs with each incision, but proven strategies exist to decrease the risk of SSI. In particular, improved adherence to evidence-based preventative measures related to appropriate antimicrobial prophylaxis can decrease the rate of SSI. Aggressive surgical debridement and effective antimicrobial therapy are needed to optimize the treatment of SSI.

Vaccine development to prevent Staphylococcus aureus surgical-site infections

BACKGROUND

Staphylococcus aureus surgical-site infections (SSIs) are a major cause of poor health outcomes, including mortality, across surgical specialties. Despite current advances as a result of preventive interventions, the disease burden of S. aureus SSI remains high, and increasing antibiotic resistance continues to be a concern. Prophylactic S. aureus vaccines may represent an opportunity to prevent SSI.

METHODS

A review of SSI pathophysiology was undertaken in the context of evaluating new approaches to developing a prophylactic vaccine to prevent S. aureus SSI.

RESULTS

A prophylactic vaccine ideally would provide protective immunity at the time of the surgical incision to prevent initiation and progression of infection. Although the pathogenicity of S. aureus is attributed to many virulence factors, previous attempts to develop S. aureus vaccines targeted only a single virulence mechanism. The field has now moved towards multiple-antigen vaccine strategies, and promising results have been observed in early-phase clinical studies that supported the recent initiation of an efficacy trial to prevent SSI.

CONCLUSION

There is an unmet medical need for novel S. aureus SSI prevention measures. Advances in understanding of S. aureus SSI pathophysiology could lead to the development of effective and safe prophylactic multiple-antigen vaccines to prevent S. aureus SSI.

Influence of Gelatin-Thrombin Matrix Tissue Sealant on Bacterial Colony Formation and Risk of Pelvic Infection

Objective. Gelatin-thrombin matrix (GTM) tissue sealant use was previously identified as an independent predictor of pelvic infection following hysterectomies. We aim to elucidate contributing factors by assessing influence of GTM on bacterial colony formation and characterizing bacteria present at the vaginal cuff. Methods. Escherichia coli was incubated in phosphate-buffered saline (PBS) and pelvic washings with and without GTM to assess influence on colony formation. Pelvic washings of the vaginal cuff were collected from hysterectomies occurring from June through October 2015. In vitro techniques, 16S rRNA gene qPCR, and 16S amplicon sequencing were performed with washings to characterize bacteria at the vaginal cuff. Results. Mean bacterial colony formation in PBS was greater for E. coli incubated in the presence of GTM (1.48 × 10(7) CFU/mL) versus without (9.95 × 10(5) CFU/mL) following 20-hour incubation (p = 0.001). Out of 61 pelvic washings samples, 3 were culture positive (≥5000 CFU/mL) with Enterococcus faecalis. Conclusion. In vitro experiments support a facilitating role of GTM on colony formation of E. coli in PBS. However, given the negative results of surgical site washings following adequate disinfection, the role of GTM in promoting posthysterectomy pelvic infections may be limited. Analysis of pelvic washings revealed presence of E. faecalis, but results were inconclusive. Further studies are recommended.

The effect of preheated versus room-temperature skin disinfection on bacterial colonization during pacemaker device implantation: a randomized controlled non-inferiority trial

Background

In clinical practice, patients who are awake often comment that cold surgical skin disinfectant is unpleasant. This is not only a problem of patients’ experience; heat loss during the disinfection process is a problem that can result in hypothermia. Evidence for the efficacy of preheated disinfection is scarce.

We tested whether preheated skin disinfectant was non-inferior to room-temperature skin disinfectant on reducing bacterial colonization during pacemaker implantation.

Methods

This randomized, controlled, non-inferiority trial included 220 patients allocated to skin disinfection with preheated (36 °C) or room-temperature (20 °C) chlorhexidine solution in 70 % ethanol. Cultures were obtained by swabbing at 4 time-points; 1) before skin disinfection (skin surface), 2) after skin disinfection (skin surface), 3) after the incision (subcutaneously in the wound), and 4) before suturing (subcutaneously in the wound).

Results

The absolute difference in growth between patients treated with preheated versus room-temperature skin disinfectant was zero (90 % CI −0.101 to 0.101; preheated: 30 of 105 [28.6 %] vs. room-temperature: 32 of 112 [28.6 %]). The pre-specified margin for statistical non-inferiority in the protocol was set at 10 % for the preheated disinfectant. There were no significant differences between groups regarding SSIs three month postoperatively, which occurred in 0.9 % (1 of 108) treated with preheated and 1.8 % (2 of 112) treated with room-temperature skin disinfectant.

Conclusion

Preheated skin disinfection is non-inferior to room-temperature disinfection in bacterial reduction. We therefore suggest that preheated skin disinfection become routine in clean surgery.

Trial registration

The study is registered at ClinicalTrials.gov (NCTO2260479).

Bacteria in hernia sac: an important risk fact for surgical site infection after incarcerated hernia repair

BACKGROUND

Although some recent reports have proven that incarcerated and/or strangulated hernia is not contraindication to mesh repair, there is still a common concern owing to increased rate of postoperative surgical site infection (SSI). The aim of this clinical study was to evaluate factors that increase the risk of SSI after incarcerated hernia repair, and to identify the pathogens related to SSI.

METHODS

A retrospective analysis was performed on data collected prospectively over a 4-year interval from January 2007 to December 2011. A total of 121 patients who underwent emergency surgery for incarcerated hernias were analyzed.

RESULTS

107 hernias were repaired using mesh versus 14 primary suture repairs. SSIs were observed in 9 of the 121 patients. Of 15 preoperative and intraoperative variables studied, duration of symptoms, diabetes mellitus, present of ileus, bowel resection or mesh repair performed, bacteria present in hernia sac and cloudy fluid in hernia sac were found to be significant factors predicting SSI. On multivariate analysis only bowel resection, duration of symptoms and bacteria present in hernia sac were independent variables. The most common pathogen found in hernia sac and cultured from wound drainage or swab was Escherichia coli. The strains of bacteria cultured from wound drainage or swab were same as those cultured from fluid in hernia sac in six of nine patients.

CONCLUSION

Gut-sourced E. coli is an important common organisms associated with SSI after incarcerated hernia repair. Prosthetic mesh could be used when no bowel resection is performed, duration of symptoms less than 24 h and fluid hernia sac is clear.

[Significance and prevention of post-operative wound complications]

Although surgical site infections (SSI) in dermatologic operative procedures are extremely rare, it is important to understand risks and etiological factors to initiate risk assessment and specific preventive measures. SSI commonly are associated with a complicated, long-term and expensive outcome. Typical wound pathogens of these infections include a variety of multiresistant organisms along with Staphylococcus aureus, Staphylococcus epidermidis, hemolytic streptococci and the gram-negative bacilli Escherichia coli and Pseudomonas aeruginosa. Effective hygienic measures as part of an adequate quality management system should consider the critical points in the development of SSI, particularly in the setting of an outpatient dermatologic unit, such as preparation of the operative area, preoperative skin antisepsis, hand hygiene, safe and skilled technique by surgeons, and barrier nursing to prevent spread of pathogens. The baseline infection incidence in dermatologic surgery inherently is low; nevertheless significant improvements can be achieved by implementation of risk-adapted infection control measures.

Adherence of surgeons to antimicrobial prophylaxis guidelines in a tertiary general hospital in a rapidly developing country

Objectives. To assess the standard practice of care of surgeons regarding surgical antibiotic prophylaxis, to identify gaps, and to set recommendations. Methods. A retrospective analysis of data obtained from different surgical units in a single center in Qatar over a 3-month period in 2012. A total of 101 patients who underwent surgery and followed regimes for surgical prophylaxis as per hospital guidelines were included in the study. Results. The overall use of antibiotic was 89%, whereas the current practice did not match the recommended hospital protocols in 53.5% of cases. Prolonged antibiotics use (59.3%) was the commonest reason for nonadherence followed by the use of an alternative antibiotic to that recommended in the protocol (31.5%) and no prophylaxis was used in 9.2% of cases. The rate of compliance was significantly higher among clean surgery than clean contaminated group (P = 0.03). Forty-four percent of clean and 65% of clean-contaminated procedures showed noncompliance with the recommended surgical antimicrobial prophylaxis hospital guidelines. Conclusion. Lack of adherence to hospital protocols is not uncommon. This finding remains a challenge to encourage clinicians to follow hospital guidelines appropriately and to consistently apply the surgical antibiotic prophylaxis. The role of clinical pharmacist may facilitate this process across all surgical disciplines.

Analysis of postoperative complications associated with the use of anti-adhesion sodium hyaluronate-carboxymethylcellulose (HA-CMC) barrier after cytoreductive surgery for ovarian, fallopian tube and peritoneal cancers

OBJECTIVE

To evaluate the risk of postoperative complications related to HA-CMC use in patients undergoing optimal cytoreductive surgery for primary and recurrent ovarian, fallopian tube, and peritoneal cancers.

METHODS

A single institution retrospective review identified all patients undergoing optimal (≤1 cm) cytoreductive surgery for primary or recurrent ovarian, fallopian tube, and peritoneal cancers between 1/95 and 12/08. Operative details and post-operative complications (<30 days) were extracted from the medical record. Fisher's exact test, Mann-Whitney-U, and multiple regression analyses were performed to identify factors, including HA-CMC use, associated with post-operative complications.

RESULTS

Three hundred seventy-five cases were analyzed: HA-CMC was utilized in 168 debulking procedures. There was no difference in the incidence of overall morbidity for patients with HA-CMC compared to those without HA-CMC (OR 1.07; 95% CI: 0.68-1.67). On univariate analysis, application of HA-CMC increased the risk of pelvic abscess (OR 2.66; 95% CI: 1.21-5.86), particularly in the primary surgery setting (OR 4.65; 95% CI: 1.67-12.98) and in patients undergoing hysterectomy (OR 3.36; 95% CI: 1.18-9.53). After controlling for confounding factors using multiple linear regression, HA-CMC use approached statistical significance in predicting an increased risk of pelvic abscess but not major postoperative morbidity.

CONCLUSIONS

HA-CMC adhesion barrier placement at the time of optimal cytoreductive surgery for ovarian, fallopian tube, and peritoneal cancer is not associated with major postoperative complications but may be associated with increased risk of pelvic abscess.

Staphylococcal surgical site infections

Staphylococcus aureus is the leading cause of surgical site infections (SSI) in the United States. In particular, SSI caused by methicillin-resistant Staphylococcus aureus (MRSA) has emerged as a devastating complication, leading to increased mortality rates, increased length of hospitalization, and increased costs. Proven strategies for prevention of SSI caused by S aureus include addressing modifiable risk factors and correct choice and timing of antimicrobial prophylaxis. Other strategies, including decolonization and the use of vancomycin, remain controversial.

Postoperative surgical site infections in cardiac surgery--an overview of preventive measures

Postoperative surgical site infections are a major cause of postoperative morbidity and mortality in cardiac surgery. A surgical site infection occurs when the contaminating pathogens overcome the host defense systems and an infectious process begins. Bacteria may enter the operating site either by direct contamination from the patient's skin or internal organs, through the hands and instruments of the surgical staff or by bacteria-carrying particles that float around in the operating theatre and may land in the wound. The ability to withstand the contaminating bacteria depends on both local and systemic host defense. Successful preventive strategies are multiple and must include: 1) Minimizing the bacterial contamination of the surgical site (skin preparation, operating room ventilation, scrubbing, double gloving, etc.), 2) Minimizing the consequences of virulent contaminating bacteria by antibiotic prophylaxis (adequate dose, sort, timing, duration), 3) Minimizing injury to local host defense (atraumatic surgery, no excessive electrocautery, meticulous hemostasis, etc.), and 4) Optimizing general host defense (nutrition, tobacco smoking, weight loss, etc.). Compliance with these preventive procedures must be enforced through regular reviews of performance. Non-compliance with hygiene routines is often due to ignorance and poor planning. Education of personnel in these issues is a continuous process.

Skin and Soft Tissue Infections in Older Adults

Skin and soft tissue infections (SSTIs) are a common cause of morbidity in older patients. Because of changes in skin consistency, immunosenescence, and the presence of underlying skin conditions and comorbid conditions, elderly persons are at high risk for SSTIs. Specific community- and hospital-associated SSTIs are reviewed in this article with particular emphasis on the epidemiology, prevention, risk factors, and treatment of SSTIs in older patients.

Cultures of sternal wound and mediastinum taken at the end of heart surgery do not predict postsurgical mediastinitis

The aim of the study was to assess of the role of intraoperative cultures taken at the end of major heart surgery (MHS) in the prediction of postoperative mediastinitis (PM) in patients undergoing MHS over a 6-month period in a tertiary university hospital. Just before wound closure, a sample of the sternal border was taken, swabbing back and forth the sternal border and the subcutaneous tissues. A second sample was taken after irrigation of the deep mediastinal structures with 10 mL of Ringer lactate. Swabs were processed semiquantitatively and the mediastinal fluid with a quantitative technique. The observation of one or more colonies per plate was considered a positive culture. Cultures obtained at the end of 229 surgical interventions (227 patients) were positive with the semiquantitative or with the quantitative procedures in 31.0% (95% confidence interval [CI], 25.1-37.4%) and 34.5% (95% CI, 28.4-41.0%) of the times, respectively (P = NS). The number of microorganisms isolated in the wound swab or mediastinal fluid was 91 and 110, respectively. Of the 227 patients, 7 developed an episode of PM (3.1%; 95% CI, 1.2-6.2%) after a median time of 11 days (range, 5-19 days). The microorganisms causing the 7 cases of mediastinitis were not isolated in the intraoperative cultures in any of the cases. The value of intraoperative cultures as a test for prediction of PM depending on the breakpoint chosen were as follows: sensitivity (0%), specificity (66.2-97.3%), and positive (0%) and negative predictive values (96.8-98.0%). We recommend against surveillance cultures taken intraoperatively in patients undergoing MHS.

Does pre- and postoperative metronidazole treatment lower vaginal cuff infection rate after abdominal hysterectomy among women with bacterial vaginosis?

OBJECTIVE

Bacterial vaginosis (BV) is a known risk factor for postoperative infection following abdominal hysterectomy. Vaginal bacterial flora scored as intermediate has been shown to have the same risk of postoperative infection as BV.

METHODS

Women undergoing total abdominal hysterectomy for benign diseases were open-randomized according to Zelen to either treatment with metronidazole rectally for at least 4 days or no treatment. At the preoperative gynecological examination a vaginal smear was collected and Gram stained. Women with BV or intermediate flora were merged to one group called abnormal vaginal flora.

RESULTS

In total 213 women were randomized to treatment or no treatment. After exclusion of 71 women, 142 women were eligible for analysis. Among the 59 women diagnosed with abnormal vaginal flora there were no vaginal cuff infections in the treated arm, compared with 27% in the 'no treatment' arm (p < 0.01). Treatment also reduced the vaginal cuff infection rate from 9.5 to 2% among the 83 women with lactobacilli flora. However, this difference was not statistically significant. Treatment had no effect on the rate of wound infections. Intention-to-treat analysis showed a significant reduction in vaginal cuff infections among women randomized to treatment.

CONCLUSION

Pre- and postoperative treatment for at least 4 days with metronidazole rectally reduces significantly vaginal cuff infection among women with abnormal vaginal flora.

Piperacillin versus cefotetan as single-dose prophylaxis in abdominal hysterectomy: a prospective, randomized, multicenter study

Five hundred and sixty-six women, consecutively admitted to nine different hospitals for elective abdominal hysterectomy, were randomized to receive a single 2 g i.v. dose of either cefotetan or piperacillin at induction of anesthesia. Five patients were excluded and 561 (287 given cefotetan and 274 given piperacillin) could be evaluated. In 10 patients (5 for each drug) the concentrations of either cefotetan or piperacillin in serum and subcutaneous tissue at the beginning and at the end of surgery and in uterus, salpinx and ovary samples, were microbiologically assessed. No significant differences could be found between cefotetan and piperacillin groups for any of the considered infectious complications (bacteremia, wound or vaginal cuff infection, pelvic cellulitis and febrile morbidity) nor for the pooled data (cefotetan group: 4.9%, piperacillin group: 5.8%, p:NS). As for the concentrations of prophylactic drugs, serum levels throughout surgery were found to be adequate.

Antimicrobial prophylaxis in surgery: mechanisms, misconceptions, and mischief

There is a major misconception among many surgeons about need for prolonged postoperative use of antimicrobial prophylaxis in preventing operative site infections. For example, among community hospital members of the Florida Consortium for Infection Control there is a mean duration of four days' use of intravenous antimicrobials in uninfected patients immediately following elective large bowel operations (Ehrenkranz NJ, unpublished data). Historically, much of the early work demonstrating antimicrobial prophylactic efficacy in large bowel operations was done at Jackson Memorial Hospital in Miami by Hiram Polk more than 20 years ago. A number of then surgical residents who took part in these studies, writing orders for only three doses of prophylactic drug, are now senior surgeons in active practice in Florida. Some of these surgeons currently prescribe prolonged postoperative courses of antimicrobials following large bowel surgery in uninfected patients. This is both mystifying and disconcerting.