The effect of whole body disinfection on intraoperative wound contamination

Surgical Site Infections at Shirati KMT Hospital in Northeastern Tanzania

Despite improved guidelines for surgical practices and better surgical methods and tools, surgical site infection (SSI) is still a common cause of morbidity and mortality with increased rates in resource-limited nations. In Tanzania, there is limited data on SSI and associated risk factors for developing an effective surveillance system for SSI. In this study, we aimed to establish for the first time the baseline SSI rate and its associated factors at the Shirati KMT Hospital in Northeastern Tanzania. We collected hospital records of 423 patients who had undergone major and minor surgeries between January 1 and June 9, 2019, at the hospital. After accounting for incomplete records and missing information, we analyzed a total of 128 patients and found an SSI rate of 10.9% and performed univariate and multivariate logistic regression analyses for elucidating the relationship between risk factors and SSI. All patients with SSI had undergone major operations. Moreover, we observed trends of increased association of SSI with patients who are 40 or younger, female, and had received antimicrobial prophylaxis or more than one type of antibiotics. In addition, patients who had received an American Society of Anesthesiologists (ASA) score of II or III, as one category, or undergone elective operations or operations lasting longer than 30 minutes were prone to develop SSI. Although these findings were not statistically significant, both univariate and multivariate logistic regression analyses showed a significant correlation between clean contaminated wound class and SSI, consistent with previous reports. The study is the first to elucidate the rate of SSI and its correlated risk factors at the Shirati KMT Hospital. We conclude that, based on the obtained data, clean contaminated wound class is a significant predictor of SSI at the hospital and that an effective surveillance system for SSI should begin with adequate record keeping of all patients' hospitalization and an efficient follow-up system. Moreover, a future study should aim to explore more widespread SSI predictors such as premorbid illness, HIV status, duration of hospitalization prior to operation, and type of surgery.

The Japan Society for Surgical Infection: guidelines for the prevention, detection, and management of gastroenterological surgical site infection, 2018

BACKGROUND

The guidelines for the prevention, detection, and management of gastroenterological surgical site infections (SSIs) were published in Japanese by the Japan Society for Surgical Infection in 2018. This is a summary of these guidelines for medical professionals worldwide.

METHODS

We conducted a systematic review and comprehensive evaluation of the evidence for diagnosis and treatment of gastroenterological SSIs, based on the concepts of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. The strength of recommendations was graded and voted using the Delphi method and the nominal group technique. Modifications were made to the guidelines in response to feedback from the general public and relevant medical societies.

RESULTS

There were 44 questions prepared in seven subject areas, for which 51 recommendations were made. The seven subject areas were: definition and etiology, diagnosis, preoperative management, prophylactic antibiotics, intraoperative management, perioperative management, and wound management. According to the GRADE system, we evaluated the body of evidence for each clinical question. Based on the results of the meta-analysis, recommendations were graded using the Delphi method to generate useful information. The final version of the recommendations was published in 2018, in Japanese.

CONCLUSIONS

The Japanese Guidelines for the prevention, detection, and management of gastroenterological SSI were published in 2018 to provide useful information for clinicians and improve the clinical outcome of patients.

No Clear Benefit of Chlorhexidine Use at Home Before Surgical Preparation

INTRODUCTION

Several studies have evaluated the efficacy of home use of chlorhexidine before surgery to reduce bacterial colonization. However, these studies have provided conflicting evidence about the potential efficacy of this strategy in decreasing bacterial loads and infection rates across surgical populations, and no prior study has analyzed the benefit of this intervention before spine surgery. We prospectively analyzed the effectiveness of chlorhexidine gluconate wipes for decreasing bacterial counts on the posterior neck.

METHODS

Sixteen healthy adults participated in this prospective study. The right side of each participant's neck was wiped twice (the night before and the morning of the experiment) with chlorhexidine gluconate wipes. The left side was used as the control region. Bacterial swabs were obtained as a baseline upon enrollment in the study, then upon arrival at the hospital, and, finally, after both sides of the neck had received standard preoperative scrubbing.

RESULTS

All patients had positive baseline bacterial growth (median >1,000 colonies/mL). When chlorhexidine gluconate wipes were used, decreased bacterial counts were noted before the preoperative scrub, but this finding was not statistically significant (P = 0.059). All patients had zero bacteria identified on either side of their neck after completion of the preoperative scrub.

CONCLUSION

At-home use of chlorhexidine gluconate wipes did not decrease the topical bacterial burden. Therefore, using chlorhexidine gluconate wipes at home before surgery may offer no added benefit.

Preoperative bathing of the surgical site with chlorhexidine for infection prevention: Systematic review with meta-analysis

BACKGROUND

Preoperative bathing with 4% chlorhexidine is recommended as a measure to prevent surgical site infection (SSI) despite uncertainty regarding the effectiveness of the intervention. This review aimed to assess the effect of bathing with 4% chlorhexidine on the prevention of SSIs in clean surgeries compared with bathing with placebo solution or soap.

METHODS

Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines for systematic reviews and the Cochrane manual were followed. Sources were MEDLINE and Latin American and Caribbean Health Sciences Literature databases and manual search of references from evaluated studies. We included randomized studies evaluating clean surgical wounds and reporting SSIs after preoperative bathing with 4% chlorhexidine.

RESULTS

A total of 243 primary studies were identified and 8 were considered methodologically appropriate based on the Jadad Scale. Data were gathered from 10,655 patients. The global SSI rate was 7.2%. The SSI rate for chlorhexidine bathing, placebo, and soap without antiseptic groups was 7.1%, 9.1%, and 5.1%, respectively. A significant reduction in the infection rates was not found in the comparison between patients subjected to preoperative bathing with 4% chlorhexidine versus placebo solution (relative risk, 0.91; 95% confidence interval, 0.76-1.09). The same absence of benefit was observed comparing chlorhexidine bathing with soap (relative risk, 1.06; 95% confidence interval, 0.68-1.66).

CONCLUSIONS

Controlled clinical trials are needed to assess the effect of preoperative chlorhexidine bathing on infection rates following clean surgery before the incorporation of this intervention in health care services.

Does Preadmission Cutaneous Chlorhexidine Preparation Reduce Surgical Site Infections After Total Knee Arthroplasty?

BACKGROUND

Many preventive methodologies seek to reduce the risk of surgical site infections after total knee arthroplasty (TKA), including the use of preoperative chlorhexidine baths and cloths. Although we have demonstrated in previous studies that this may be an efficacious method for infection prevention, our study was underpowered and we therefore set out to evaluate this with a larger sample size.

QUESTIONS/PURPOSES

(1) Does a preadmission chlorhexidine cloth skin preparation protocol decrease the risk of surgical site infection in patients undergoing TKA? (2) When stratified using the National Healthcare Safety Network (NHSN) risk categories, which categories are associated with risk reduction from the preadmission chlorhexidine preparation protocol?

METHODS

In our study, all patients (3717 total) who had undergone primary or revision TKA at a single institution between January 1, 2007, and December 31, 2013, were identified, of whom 991 patients used the chlorhexidine cloths before surgery and 2726 patients did not. All patients were provided cloths with instructions before surgery; however, as a result of a lack of compliance, we were able to substratify patients into treatment and control cohorts. Additionally, we substratified patients by NHSN risk category to determine differences in infection between the two cohorts (cloth versus no cloth). Patient medical records and an infection-tracking database were reviewed to determine the development of periprosthetic infection (patients who had superficial infections were excluded from our study) in both groups after 1 year surveillance. We then calculated relative risk reductions with use of chlorhexidine gluconate and stratified results based on NHSN risk category.

RESULTS

Use of a preoperative chlorhexidine cloth skin preparation protocol is associated with reduced relative risk of periprosthetic infection after TKA (infections with protocol: three of 991 [0.3%]; infections in control: 52 of 2726 [1.9%]; relative risk [RR]: 6.3 [95% confidence interval [CI], 1.9-20.1]; p = 0.002). When stratified by NHSN risk category, periprosthetic infection risk reduction was seen in the medium-risk category (protocol: one of 402 [0.3%]; control: 25 of 1218 [2.0%]; RR, 8.3 [CI, 1.1-60.7]; p = 0.038), but no significant difference was detected in the low- and medium-risk groups (RR, 2.1 [CI, 0.5-9.6; p = 0.33] and RR, 11.3 [CI, 0.7-186.7; p = 0.09]).

CONCLUSIONS

A prehospital chlorhexidine gluconate wipe protocol appears to reduce the risk of periprosthetic infections after TKA, primarily in those patients with medium and high risk. Although future multicenter randomized trials will need to confirm these preliminary findings, the intervention is inexpensive and is unlikely to be risky and therefore might be considered on the basis of this retrospective, comparative study.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Preoperative chlorhexidine shower or bath for prevention of surgical site infection: a meta-analysis

BACKGROUND

Chlorhexidine showering is frequently recommended as an important preoperative measure to prevent surgical site infection (SSI). However, the efficacy of this approach is uncertain.

METHODS

A search of electronic databases was undertaken to identify prospective controlled trials evaluating whole-body preoperative bathing with chlorhexidine versus placebo or no bath for prevention of SSI. Summary risk ratios were calculated using a DerSimonian-Laird random effects model and a Mantel-Haenzel dichotomous effects model.

RESULTS

Sixteen trials met inclusion criteria with a total of 17,932 patients: 7,952 patients received a chlorhexidine bath, and 9,980 patients were allocated to various comparator groups. Overall, 6.8% of patients developed SSI in the chlorhexidine group compared with 7.2% of patients in the comparator groups. Chlorhexidine bathing did not significantly reduce overall incidence of SSI when compared with soap, placebo, or no shower or bath (relative risk, 0.90; 95% confidence interval: 0.77-1.05, P = .19).

CONCLUSIONS

Meta-analysis of available clinical trials suggests no appreciable benefit of preoperative whole-body chlorhexidine bathing for prevention of SSI. However, most studies omitted details of chlorhexidine application. Better designed trials with a specified duration and frequency of exposure to chlorhexidine are needed to determine whether preoperative whole-body chlorhexidine bathing reduces SSI.

Predictors of surgical site infections among patients undergoing major surgery at Bugando Medical Centre in Northwestern Tanzania

Background

Surgical site infection (SSI) continues to be a major source of morbidity and mortality in developing countries despite recent advances in aseptic techniques. There is no baseline information regarding SSI in our setting therefore it was necessary to conduct this study to establish the prevalence, pattern and predictors of surgical site infection at Bugando Medical Centre Mwanza (BMC), Tanzania.

Methods

This was a cross-sectional prospective study involving all patients who underwent major surgery in surgical wards between July 2009 and March 2010. After informed written consent for the study and HIV testing, all patients who met inclusion criteria were consecutively enrolled into the study. Pre-operative, intra-operative and post operative data were collected using standardized data collection form. Wound specimens were collected and processed as per standard operative procedures; and susceptibility testing was done using disc diffusion technique. Data were analyzed using SPSS software version 15 and STATA.

Results

Surgical site infection (SSI) was detected in 65 (26.0%) patients, of whom 56 (86.2%) and 9 (13.8%) had superficial and deep SSI respectively. Among 65 patients with clinical SSI, 56(86.2%) had positive aerobic culture. Staphylococcus aureus was the predominant organism 16/56 (28.6%); of which 3/16 (18.8%) were MRSA. This was followed by Escherichia coli 14/56 (25%) and Klebsiella pneumoniae 10/56 (17.9%). Among the Escherichia coli and Klebsiella pneumoniae isolates 9(64.3%) and 8(80%) were ESBL producers respectively. A total of 37/250 (14.8%) patients were HIV positive with a mean CD4 count of 296 cells/ml. Using multivariate logistic regression analysis, presence of pre-morbid illness (OR = 6.1), use of drain (OR = 15.3), use of iodine alone in skin preparation (OR = 17.6), duration of operation ≥ 3 hours (OR = 3.2) and cigarette smoking (OR = 9.6) significantly predicted surgical site infection (SSI)

Conclusion

SSI is common among patients admitted in surgical wards at BMC and pre-morbid illness, use of drain, iodine alone in skin preparation, prolonged duration of the operation and cigarette smoking were found to predict SSI. Prevention strategies focusing on factors associated with SSI is necessary in order to reduce the rate of SSI in our setting.

Use of a surgical preparation and sterile dressing change during office visit treatment of chronic foot and ankle wounds decreases the incidence of infection and treatment costs

Foot and ankle surgeons work with a patient population burdened by multiple factors that adversely affect wound healing and the ability to combat infection. As a result, many of these patients are seen for treatment of chronic ulcerations on their lower extremities that are highly susceptible to colonization and possible progression to a limb- and/or life-threatening infection. The Limb Preservation Service at the Madigan Army Medical Center hypothesized that implementation of a standardized protocol involving a formal physician-directed surgical preparation of the affected lower extremity and a physician-applied sterile dressing at each outpatient clinic appointment would reduce the incidence of infection, use of systemic antibiosis, and thus the requirement for frequent follow-up office appointments. Initiation of this protocol resulted in the reduction of infection to the extent that antibiotic need was eliminated. The frequency of office visits required for follow-up was also significantly reduced. This is key in treating a patient population in which the financial burden to treat chronic wounds and associated infections represents a large portion of the health care money spent for their medical care.

Bandages, dressings, and cranial neurosurgery

OBJECT

Bandages and dressings are commonly applied to incisional scalp wounds to prevent complications, particularly infection, during the early stages of wound healing. Bandaging cranial incisional wounds requires resources, consumes healthcare workers' time, and incurs expense; it is therefore important to examine its efficacy.

METHODS

All cranial operations (excluding shunt placements, procedures on the scalp alone, and bur hole procedures) performed between June 30, 2001 and January 1, 2006, by two neurosurgeons at either of two hospitals, one adult and one pediatric institution, were reviewed. Surgical site infections (SSIs) and other postoperative complications were investigated with respect to the use of bandaging for incisional wounds and other aspects of postoperative wound management. The operations were classified into four categories based on wound type: "clean," "clean-contaminated," "contaminated," and "dirty," according to the criteria of the Centers for Disease Control and Prevention.

CONCLUSIONS

A total of 702 operations were performed in 577 patients; only five patients received any type of surgical bandaging. There were four SSIs (0.57%; 95% confidence interval [CI] 0.16-1.45). The postoperative infection rate in the 626 clean cases was 0.48% (95% CI 0.10-1.39) and was 2.63% (95% CI 0.07-13.81) in the 38 clean-contaminated cases. The data obtained in this investigation is consistent with the position that bandaging incisional scalp wounds after cranial surgery adds little if any benefit beyond the easier, simpler, and cheaper practice of using antibiotic ointment as a dressing without bandaging.

The effect of thorough preoperative disinfection on the incidence of postoperative mediastinitis

This study was conducted to evaluate the effectiveness of scrubbing the skin of patients scheduled to undergo elective cardiac surgery with disinfectant solutions in an attempt to reduce the incidence of the potentially fatal postoperative complication of mediastinitis. Since April 1991, we have routinely disinfected the skin of all such patients three times preoperatively. A retrospective comparison of the incidence of mediastinitis before and after April 1991 was carried out. Microbiological examinations of the anterior chest were conducted in ten patients admitted for elective operations, and in four patients admitted for emergency surgery. Specimens were obtained before each scrubbing, before the operation, and just after skin closure. There was a significant decrease in the general incidence of mediastinitis after April 1991 (P < 0.01). Microbiologically, significant decreases in colony counts were also observed after the first (P < 0.05) and second scrubbing (P < 0.05) in the ten patients specifically studied before elective surgery. No colonies grew in the postoperative specimens from any of these patients, but colony formations were observed in two of the four patients who underwent emergency surgery (P = 0.066). Thus, we conclude that our thorough disinfection method effectively achieves adequate, prolonged suppression of the skin flora, which explains the marked decrease in the incidence of mediastinitis in our hospital since its institution.

Principles of closed surgical wound care

A review of the factors before, during and after surgical procedures that may predispose patients to post-operative wound infection

Does the addition of pre-operative skin preparation with povidone-iodine reduce groin sepsis following arterial surgery?

Sixty-four consecutive patients undergoing elective vascular surgery involving exposure of the femoral artery at the groin were randomized to one of two groups. Group A (N = 34) received twice-daily skin preparation with 10% aqueous povidone-iodine for 48 h preoperatively, while group B (N = 30) did not. Both groups were examined on a daily basis following surgery and any discharge from the wound was recorded and sent for bacteriological culture. The groups were well matched for age, sex and the type of vascular graft material used. In group A there were six (18.7%) groin wound infections and in group B there were five (17.2%). In this series of patients the addition of preoperative skin preparation with 10% povidone-iodine to standard peri-operative prophylaxis had no effect on the incidence of postoperative groin wound sepsis.

A method for multiple synchronous collection of airborne organisms and the effects on colony counts of various processing procedures

A method is described for synchronous collection on agar of 10 similar specimens of airborne bacterial colony-forming units (cfu) for comparative experiments. The system delivers 50 to 100 cfu per specimen with a coefficient of variance of 13 among the 10 specimens. After collection, different methods for removing colonies from the agar surface and counting them were employed. A progressive increase in colony counts was noted when increasingly destructive procedures were used. The increases noted were 4% by wetting, 30% by jet lavage, 58% by pulsed jet lavage, 82% by blending, 130% by spreading and 340% by grinding. As airborne cfu consist mainly of skin squames with multiple organisms attached, disruption of cfu is proposed as the cause of the increases. Membrane filtration of wash fluid containing cfu from the air resulted in a 47% decrease in colony counts when compared with pour-plating. Destructive processing techniques also resulted in increased variability in colony counts. The break up of occasional exceptionally large cfu is a probable explanation. The procedure described is suitable for investigating the behaviour of airborne micro-organisms and can be modified to model surgical wound contamination by replacing the agar with tissue.