Infection Rate after Cranial Neurosurgical Procedures: A Prospective Single-Center Study

Practical Guidance for Clinical Microbiology Laboratories: Microbiologic diagnosis of implant-associated infections

SUMMARYImplant-associated infections (IAIs) pose serious threats to patients and can be associated with significant morbidity and mortality. These infections may be difficult to diagnose due, in part, to biofilm formation on device surfaces, and because even when microbes are found, their clinical significance may be unclear. Despite recent advances in laboratory testing, IAIs remain a diagnostic challenge. From a therapeutic standpoint, many IAIs currently require device removal and prolonged courses of antimicrobial therapy to effect a cure. Therefore, making an accurate diagnosis, defining both the presence of infection and the involved microorganisms, is paramount. The sensitivity of standard microbial culture for IAI diagnosis varies depending on the type of IAI, the specimen analyzed, and the culture technique(s) used. Although IAI-specific culture-based diagnostics have been described, the challenge of culture-negative IAIs remains. Given this, molecular assays, including both nucleic acid amplification tests and next-generation sequencing-based assays, have been used. In this review, an overview of these challenging infections is presented, as well as an approach to their diagnosis from a microbiologic perspective.

An update on a persisting challenge: A systematic review and meta-analysis of the risk factors for surgical site infection post craniotomy

BACKGROUND

Surgical site infections (SSIs) postcraniotomy continue to impose a significant burden on health care systems and patient outcomes. It is, therefore, important to understand their risk factors in order to promote effective preventative measures. This meta-analysis aims to provide a comprehensive, up-to-date analysis of the risk factors associated with SSIs in neurosurgical procedures.

METHODS

A systematic review was conducted as per preferred reporting items for systematic reviews and meta-analysis guidelines to explore existing primary evidence on the risk factors for SSIs postcraniotomy. A comprehensive search of MEDLINE, EMBASE, and Pubmed was performed from database inception up to June 2023. 43 studies were included in the meta-analysis, encompassing a total of 68,881 patients.

RESULTS

The strongest predictor for SSIs was found to be cerebrospinal fluid (CSF) leak (OR: 8.91, CI: 4.30-18.44). Other significant factors included infratentorial surgery (OR: 0.43, CI: 0.31-0.61), emergency surgery (OR: 1.41, CI: 1.05-1.91), reintervention (OR: 3.19, CI: 1.77-5.75), prolonged operative time (mean difference: 33.25; CI: 18.83-47.67), hospital length of stay (mean difference: 0.60; CI: 0.23-0.98) and intracranial pressure monitor (ICPM) insertion (OR: 1.81; CI: 1.06-3.11). Contrarily, sex, body mass index (BMI), diabetes, antibiotic prophylaxis, immunosuppressive agents, trauma, use of artificial implants did not demonstrate statistical significance.

CONCLUSIONS

This meta-analysis provides an up-to-date and comprehensive evaluation of risk factors for SSIs postcraniotomy. It emphasizes the need for preventive strategies, particularly against CSF leaks, and calls for further research to elucidate the intricate relationships between these factors.

Clinical benefits of therapeutic drug monitoring of vancomycin therapy in patients with postoperative intracerebral hemorrhage: a retrospective cohort study

OBJECTIVE

The objective of this study was to investigate the clinical efficacy and safety of conducting therapeutic drug monitoring (TDM) of vancomycin in patients with postoperative intracerebral haemorrhage.

METHODS

We conducted a retrospective analysis of 435 patients who experienced postoperative cerebral haemorrhage and were treated with vancomycin in the Department of Neurosurgery of Inner Mongolia Autonomous Region People's Hospital from January 2017 to December 2021. Patients were then matched using the propensity score matching method in a ratio of 1:1. Ninety-two pairs of cases were successfully matched, and the data before and after performing vancomycin TDM were analysed.

RESULTS

After PSM, the baseline data of the two groups were balanced. There were no significant differences in the 14-day mortality and length of hospital stay (p>0.05) between the two groups. Compared with the non-TDM group, the TDM group had a higher proportion of patients with normal white blood cells (83.7% vs 56.5%, p=0.000), neutrophil count (57.6% vs 25.0%, p=0.000) and attaining desirable reductions of 80% in procalcitonin (65.2% vs 10.9%, p=0.000) and C-reactive protein (78.3% vs 41.3%, p=0.000) levels. At US$15.82 per additional TDM, TDM significantly promoted patient outcomes, as seen in improvements in the proportion of patients attaining desirable levels of white blood cells, neutrophil count, procalcitonin and C-reactive protein.

CONCLUSIONS

Vancomycin TDM is a safe and effective approach for the treatment of patients with postoperative intracerebral haemorrhage. The empirical use of TDM of vancomycin significantly improved normal values of white blood cells and neutrophil count, achieved desirable reductions of 80% in procalcitonin and C-reactive protein, and reduced nephrotoxicity in patients with postoperative intracerebral haemorrhage.

Effectiveness of outpatient parenteral antimicrobial therapy (OPAT) for patients with cranial infection

Objective

Outpatient parenteral antimicrobial therapy (OPAT) is a well-established and cost-effective method for improving the efficient use of healthcare resources. However, only a few centres in Germany perform it. Here we analysed OPAT for the treatment of patients with cranial infections in our neurosurgical department.

Methods

This retrospective study analysed patients with cranial infections and the need for intravenous (i.v.) antimicrobial treatment between 2018 and 2021.All diagnosed intracranial infections were defined into two infection categories such as long-term antimicrobial treatment and short-term antimicrobial treatment. All included patients were discharged with a peripherally inserted central catheter (PICC) line. Prior to discharge, all patients received training in the safe administration of their medications via the PICC line. The duration of OPAT and the rate of readmission after OPAT were analysed.

Results

We identified a total of 45 patients treated with OPAT for cranial infections. Intradural involvement was present in 40 cases (88.9%). The average length of hospital stay for this cohort after surgical treatment was 45 ± 15 days. 5 patients were treated for soft tissue/skin infection. Surgery was not required in this cohort. The mean hospital stay for this cohort was 8 ± 6 days. Gram-positive organisms were isolated in most cases (53.3%). The most common pathogens were Staphylococcus aureus followed by other Staphylococcus species. For all included patients, OPAT was performed after discharge for an average of 43.1 ± 14 days. There were five cases of readmission due to treatment failure. No serious adverse events or complications of OPAT were observed.

Conclusion

OPAT enables better patient-centred healthcare close to home. The length of hospital stay can be reduced and adverse events due to prolonged hospitalisation can be avoided.

Association of Preoperative Glycated Hemoglobin and Early Postoperative Infections After Elective Craniotomy: A Retrospective Cohort Study

BACKGROUND

The prognostic value of preoperative glycated hemoglobin (HbA1c) testing is controversial. The available evidence on the role of preoperative HbA1c in predicting postoperative complications after different surgical procedures has been conflicting. The primary aim of our retrospective observational cohort study was to assess the association between preoperative HbA1c and postoperative infections after elective craniotomy.

METHODS

We extracted and analyzed data from an internal hospital database on 4564 patients who underwent neurosurgical intervention from January 2017 to May 2022. The primary outcome measure of the present study was infections established in the first week after surgery using the Centers for Disease Control and Prevention criteria. The records were stratified by the HbA1c values and intervention types.

RESULTS

For patients who had undergone brain tumor removal with a preoperative HbA1c ≥6.5%, the odds of early postoperative infections were increased (odds ratio, 2.08; 95% confidence interval, 1.16-3.72; P = 0.01). We found no association between HbA1c and early postoperative infections for patients who had undergone elective cerebrovascular intervention, cranioplasty, or a minimally invasive procedure. After adjusting for age and gender, the threshold for significant infection risk for neuro-oncological patients increased with an HbA1c ≥7.5% (adjusted odds ratio, 2.97; 95% confidence interval, 1.37-6.45; P = 0.0058).

CONCLUSIONS

For patients undergoing elective intracranial surgery for brain tumor removal, a preoperative HbA1c ≥7.5% is associated with a higher infection rate within the first postoperative week. Future prospective studies are required to assess the prognostic value of this association for clinical decision-making.

Understanding bacterial biofilms: From definition to treatment strategies

Bacterial biofilms are complex microbial communities encased in extracellular polymeric substances. Their formation is a multi-step process. Biofilms are a significant problem in treating bacterial infections and are one of the main reasons for the persistence of infections. They can exhibit increased resistance to classical antibiotics and cause disease through device-related and non-device (tissue) -associated infections, posing a severe threat to global health issues. Therefore, early detection and search for new and alternative treatments are essential for treating and suppressing biofilm-associated infections. In this paper, we systematically reviewed the formation of bacterial biofilms, associated infections, detection methods, and potential treatment strategies, aiming to provide researchers with the latest progress in the detection and treatment of bacterial biofilms.

Nomogram Analysis of Clinical Characteristics and Mortality Risk Factor of Non-Fermentative Gram-Negative Bacteria-Induced Post-Neurosurgical Meningitis

Objective

To explore the clinical characteristics of post-neurosurgical meningitis (PNM) patients infected with nonfermenting Gram-negative bacilli (NFGNB) and to evaluate the related mortality risk factors.

Methods

A cohort analysis of PNM patients infected with NFGNB in Beijing Tiantan Hospital and Capital Medical University from 2012.1 to 2020.12. The microbial distribution, antimicrobial sensitivity and genotypes were tested, and potential mortality risk factors were evaluated using Mann–Whitney U or chi-squared tests. Independent risk factors for mortality were established by constructing a logistic model.

Results

A total of 2940 PNM patients were enrolled in this study, of whom 207 (17.1%) were infected with NFGNB. Among these patients, 29 died of NFGNB meningitis, with an overall mortality rate of 14.0%. The top three NFGNBs were Acinetobacter baumannii (105 cases, 50.7%), Pseudomonas aeruginosa (29 cases, 14.0%) and Acinetobacter lwoffii (20 cases, 9.7%). Nomogram analysis revealed that hypertension (OR 4.551, 95% CI: 1.464–14.154, P = 0.009), external ventricular drainage (EVD) (OR 3.944, 95% CI: 1.286–12.095, P = 0.016), and assisted mechanical ventilator (AMV) (OR 6.192, 95% CI: 1.737–22.081, P = 0.005) were independent risk factors for mortality. In addition, antibiotic prophylaxis was shown to play a vital role in NFGNB-induced PNM therapy.

Conclusion

PNM patients infected with NFGNB have a high mortality rate. Hypertension, EVD and AMV were independent mortality risk factors, and clinical attention should be paid to their prevention and treatment.

Severe Intraoperative Hyperglycemia and Infectious Complications After Elective Brain Neurosurgical Procedures: Prospective Observational Study

BACKGROUND

Postoperative infections after brain surgery are a serious complication potentially worsening the outcome of surgical treatment. Severe intraoperative hyperglycemia (SIH) contributes to both infectious and noninfectious postoperative complications. However, there are a lack of data on the incidence of SIH in patients undergoing elective neurosurgical brain procedures and its association with the risk of postoperative infections.

METHODS

A total of 514 patients were prospectively enrolled in this single-center observational cohort clinical study to assess the incidence of SIH (blood glucose concentration [BGC] ≥180 mg/dL) in adult patients undergoing elective brain neurosurgical procedures and its association with postoperative infections. Both nondiabetic and diabetic patients were included in the study. BGC was determined by whole-blood analyses taken at the beginning and at the end of the surgery. Diagnosis of infection (wound, pulmonary, blood stream, urinary tract infection, or central nervous system infection) was established according to US Centers for Disease Control and Prevention (CDC) criteria within the first postoperative week.

RESULTS

SIH was recorded in at least 1 blood sample in 23 patients (4.5%). Infectious complications within the first postoperative week were diagnosed in 40 patients (7.8%). Five of 23 patients (22%) with SIH had postoperative infections, compared with 35 of 491 patients (7%) without SIH (odds ratio [OR] = 3.71; 95% confidence interval [CI], 1.24-11.09; P = .018 after fitting a multiple logistic regression model to adjust for age, body mass index [BMI], and surgery duration). Intraoperative BGC >140 mg/dL was also associated with an increased risk of postoperative infections (OR = 3.10; 95% CI, 1.43-6.75; P = .004). Elevated preoperative glycated hemoglobin (HbA1c) concentration was also associated with postoperative infections in the study population (OR = 2.4; 95% CI, 1.02-6.00; P = .045). Age, BMI, American Society of Anesthesiologists (ASA) physical status, type of surgery, and duration of intervention had no significant association with the postoperative infection rate.

CONCLUSIONS

SIH is associated with a higher risk of infections within the first postoperative week in patients undergoing elective brain neurosurgical procedures. Preoperative HbA1c is a reliable marker of the potential risk both of SIH and postoperative infections in the selected cohort. Future studies need to assess possible improvements in outcome under more precise monitoring and tighter control of perioperative hyperglycemia.

Environmental, Microbiological, and Immunological Features of Bacterial Biofilms Associated with Implanted Medical Devices

The spread of biofilms on medical implants represents one of the principal triggers of persistent and chronic infections in clinical settings, and it has been the subject of many studies in the past few years, with most of them focused on prosthetic joint infections. We review here recent works on biofilm formation and microbial colonization on a large variety of indwelling devices, ranging from heart valves and pacemakers to urological and breast implants and from biliary stents and endoscopic tubes to contact lenses and neurosurgical implants. We focus on bacterial abundance and distribution across different devices and body sites and on the role of environmental features, such as the presence of fluid flow and properties of the implant surface, as well as on the interplay between bacterial colonization and the response of the human immune system.

Systematic Review of Enhanced Recovery After Surgery in Patients Undergoing Cranial Surgery

BACKGROUND

Enhanced Recovery after Surgery (ERAS) pathways are increasingly being integrated in neurosurgical patient management. The full extent of ERAS in cranial surgery is not well studied. We performed a systematic review examining ERAS in cranial surgery patients to 1) identify the extent to which ERAS is integrated in cranial neurosurgical procedures and 2) assess effectiveness of ERAS interventions for patients undergoing these procedures.

METHODS

A systematic review of MEDLINE, Embase, the Cochrane Central Register of Controlled Trials, Scopus, PsychInfo, and Google Scholar was conducted according to PRISMA guidelines (CRD42020197187). Studies eligible for inclusion assessed patients undergoing any cranial surgical procedure using an ERAS or ERAS-like pathway, defined by ≥2 ERAS protocol elements per the ERAS Society's RECOvER Checklist and the recommendations of Hagan et al. 2016 (not including patient education, criteria for discharge, or tracking of postdischarge outcomes).

RESULTS

Nine studies were included in qualitative synthesis, 2 of which were randomized controlled trials. All studies showed a moderate risk of bias. The most common ERAS elements used were screening and/or optimization and formal discharge criteria. The least common ERAS elements used were fasting/carbohydrate loading and antithrombotic prophylaxis. Complication rates were similar in studies comparing ERAS with non-ERAS groups. ERAS interventions were associated with reduced length of stay, with comparable and/or improved patient satisfaction.

CONCLUSIONS

ERAS is a safe and potentially favorable perioperative pathway for select patients undergoing cranial surgery. Future studies of ERAS in cranial surgery patients should emphasize postoperative optimizations and patient-reported outcome measures as key features.

Phenotype, molecular characterisation and risk factors for postoperative meningitis caused by ESBL-producing-Enterobacteriaceae: a six years multi-Centre comparative cohort study

BACKGROUND

To determine the phenotype, molecular characterisation and risk factors of postoperative meningitis induced by Extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae (EPE) in China.

METHODS

We performed a multi-centre comparative cohort study of postoperative meningitis patients infected with Enterobacteriaceae in 4 neurosurgical centres in China from January 2014 to December 2019. Phenotype and molecular characteristics of the isolates were reviewed and tested, and independent risk factors of the EPE meningitis were evaluated by binary logistic regression.

RESULTS

In total, 220 Enterobacteriaceae include 78 EPE were available in this study. 85.6% (67/78) ESBL-related genes were tested, and blaSHV (14.9%) and blaSHV + blaTEM + blaCTX-M-9 (20.9%) were found to be the most frequent mono and combined ESBL-related genes harboured by Enterobacteriaceae. On binary logistic analysis, craniotomy (OR. 2.583, 95% C.I. 1.274-5.235, P = 0.008) and malignancy (OR. 2.406, 95% C.I. 1.299-4.456, P = 0.005) were the associated independent risk factors to meningitis induced by EPE.

CONCLUSIONS

To the best of our knowledge, this is the largest series focusing on risk factors of EPE meningitis which has been conducted in China. Craniotomy and malignancy were independent risk factors for EPE meningitis. The risk factors identified may be further utilized in clinical practice and research to avoid and reduce the mortality in future.

Preoperative antibiotic prophylaxis regimen in brain tumour surgery in Sweden: a quasi-experimental study

Background

There has been varied clinical practice concerning antibiotic prophylaxis in patients undergoing craniotomy. In Sweden, both Cloxacillin and Cefuroxime have frequently been used. We aimed to study the clinical effectiveness of these two regimens.

Methods

A quasi-experimental design was used. The sample consisted of 580 adult (> 18 years) patients operated 2012–2015, of which 375 received Cloxacillin (pre-intervention group) and 205 received Cefuroxime (intervention group). Primary endpoint was the incidence of surgical site infection (SSI) 12 months after surgery, while secondary endpoints were the need for reoperation due to SSI, the amount antibiotics used and the number of visits in the outpatient clinic related to SSI. A control group from another institution was reviewed to rule out clinical trial effects.

Results

When analysed by intention to treat, the pre-intervention group had a significant higher incidence of SSI, 13.3% (50/375) vs 5.4% (11/205) in the intervention group (p < 0.01). A treatment per protocol analysis confirmed the result. The number of reoperations due to SSI were significantly reduced in the intervention group, 3.4% (7/205) vs 8.3% (31/375) (p = 0.02), as was the total antibiotic use (p = 0.03) and the number of visits in the outpatient clinic (p < 0.01). In the control group, the reoperation rate as result of SSI was lower (p = 0.02) prior to the opposite change from Cefuroxime to Cloxacillin, 1.8% (27/1529) vs 3.1% (43/1378).

Conclusion

In Sweden, Cefuroxime as prophylaxis in brain tumour surgery by craniotomy seems to be superior to Cloxacillin.

Implementation of an infection prevention bundle is associated with reduced surgical site infections in cranial neurosurgery

OBJECTIVE

The objective of this study was to quantify surgical site infection (SSI) rates after cranial neurosurgery in a tertiary care hospital, identify risk factors for SSI, and evaluate the impact of standardized surveillance and an infection prevention bundle (IPB).

METHODS

The authors compared SSI rates during 7 months before and after the intervention. The IPB included standardized patient preparation, perioperative antibiotic/antiseptic use, barrier precautions, coaching of surgeons, and the implementation of a specialized technical operation assistant team.

RESULTS

Three hundred twenty-two unselected consecutive patients were evaluated before the IPB, and 296 were evaluated after implementation. Infection rates after 1 year decreased from 7.8% (25/322) to 3.7% (11/296, p = 0.03) with similar mortality rates (14.7% vs 13.8%, p = 0.8). The isolated bacteria included Staphylococcus aureus (42%), Cutibacterium acnes (22%), and coagulase-negative staphylococci (14%). Organ/space infections dominated with 67%, and mostly consisted of subdural empyema and meningitis/ventriculitis. Among the 36 SSIs, 13 (36%) occurred during hospitalization, and 29 (81%) within the first 3 months of follow-up. In multivariable analysis including established risk factors described in the literature, non-CNS neoplasia (odds ratio [OR] 3.82, 95% confidence interval [CI] 1.39–10.53), postoperative bleeding (OR 4.09, 1.44–11.62), operations performed by or under supervision of a senior faculty surgeon (OR 0.38, 0.17–0.84), and operations performed after the implementation of standardized surveillance and an IPB (OR 0.38, 0.17–0.85) significantly influenced the infection rate.

CONCLUSIONS

The introduction of an IPB combined with routine surveillance and personal feedback was associated with a 53% reduced infection rate. The lower infection rates of senior faculty and the strong association between postoperative bleeding and infection underline the importance of both surgical experience as well as thorough supervision and coaching of younger surgeons.

Evaluation of neurosurgical implant infection rates and associated pathogens: evidence from 1118 postoperative infections

OBJECTIVE

Various implanted materials are used in neurosurgery; however, there remains a lack of pooled data on infection rates (IRs) and infective bacteria over past decades. The goal of this study was to investigate implant infections in neurosurgical procedures in a longitudinal retrospective study and to evaluate the IRs of neurosurgically implanted materials and the distribution of pathogenic microorganisms.

METHODS

A systematic literature search was conducted using PubMed and Web of Science databases for the time period between 1968 and 2018. Neurosurgical implant infections were studied in 5 subgroups, including operations or diseases, implanted materials, bacteria, distribution by country, and time periods, which were obtained from the literature and statistically analyzed. In this meta-analysis, statistical heterogeneity across studies was tested by using p values and I2 values between studies of associated pathogens. Egger’s test was used for assessing symmetries of funnel plots with Stata 11.0 software. Methodological quality was assessed to judge the risk of bias according to the Cochrane Handbook.

RESULTS

A total of 22,971 patients from 227 articles satisfied the study’s eligibility criteria. Of these, 1118 cases of infection were reported, and the overall IR was 4.87%. In this study, the neurosurgical procedures or disorders with the top 3 IRs included craniotomy (IR 6.58%), cranioplasty (IR 5.89%), and motor movement disorders (IR 5.43%). Among 13 implanted materials, the implants with the top 3 IRs included polypropylene-polyester, titanium, and polyetheretherketone (PEEK), which were 8.11%, 8.15%, and 7.31%, respectively. Furthermore, the main causative pathogen was Staphylococcus aureus and the countries with the top 3 IRs were Denmark (IR 11.90%), Korea (IR 10.98%), and Mexico (IR 9.26%). Except for the low IR from 1998 to 2007, the overall implant IR after neurosurgical procedures was on the rise.

CONCLUSIONS

In this study, the main pathogen in neurosurgery was S. aureus, which can provide a certain reference for the clinic. In addition, the IRs of polypropylene-polyester, titanium, and PEEK were higher than other materials, which means that more attention should be paid to them. In short, the total IR was high in neurosurgical implants and should be taken seriously.

Risk factors for meningitis in neurosurgical patients with cerebrospinal fluid drains: prospective observational cohort study

BACKGROUND

Cerebrospinal fluid (CSF) drainage or intracranial pressure (ICP) monitoring devices are life-saving devices. We examined the risk factors for infections related to them and assessed the effect of an infection control (IC) intervention.

METHODS

A prospective observational study was conducted in the Neurosurgical Department of our hospital between 2014 and 2017. We included all consecutive patients undergoing CSF catheter insertions, including external ventricular drainage (EVD), lumbar drainage (LD), and ICP catheters. An IC intervention was implemented between March and August 2016. We examined risk factors for meningitis or ventriculitis, defined according to Healthcare-associated infections surveillance definitions, on univariate and multivariate analysis.

RESULTS

A total of 232 patients with 437 drains (212 EVDs, 92 LDs, and 133 ICPs) were included. On univariate and multivariate analysis, the infection incidence was 13.7 per 1000 drain days (17.3/1000 before IC intervention, 7.9/1000 during, and 9.2/1000 after the intervention). Most episodes were caused by Gram-negative bacteria, and the most common pathogen was Acinetobacter baumanii. Risk factors for infection per patient included diabetes mellitus (p = 0.017), CSF leak (p = 0.032), drain opening (p = 0.027), and the duration of the drain in days (p = 0.035). Risk factors per catheter included drain opening (p < 0.001), drain days (p = 0.001), and the IC intervention period compared to before the intervention period (p = 0.037). When restricting the analysis to EVDs, drain days (p = 0.001) was the only significant risk factor.

CONCLUSIONS

Strict adherence to IC, shortening drain duration, and avoiding unnecessary opening and manipulation of the drains are crucial to preventing neurosurgical drain infections.

Incidence and risk factors of neurosurgical site infections: results of a prospective multicenter cohort study on 6359 surgeries

BACKGROUND

Neurosurgical surgical site infections (SSI) are life-threatening complications, requiring medical treatment and additional surgeries and remain a substantial cause of morbidity. In order to identify the incidence and the main risk factors for SSI, we developed the Prophylaxis with Antibiotic Protocol for Neurosurgical Site Infections Study (PASSIS), a prospective observational multicenter cohort study for examining a large number of neurosurgical procedures.

METHODS

The study PASSIS involved four Italian departments of neurosurgery applying the same antibiotic prophylaxis (ABP) protocol on 6359 consecutive neurosurgical procedures. In high-risk conditions (intra-operative contamination and/or postoperative cerebro-spinal fluid [CSF], and/or subcutaneous drainage and/or postoperative hyperpyrexia) and in presence of wound complication (CSF leak and/or CSF collection and/or wound diastasis), a prolongation protocol was prescribed.

RESULTS

The crude rate of SSI in the whole series was and 1.7% for patient and 1.5% for procedure. Patient related SSI risk factors: Younger patients (≤14 years) had a significantly higher SSI risk compared with older patients (RR: 2.17; 95% CI: 1.13-4.14). Patients underwent two surgeries were at increased SSI risk (RR: 3.80; 95% CI: 2.33-6.18), and the risk increased with the number of surgeries. Surgeries lasting longer than 3 hours (RR: 2.27; 95% CI: 1.15-4.50), undergoing two or more surgeries and the presence of prosthetic implants (RR: 2.40; 95% CI: 1.53-3.77) were procedure related SSI risk factors positively associated with SSI. In high-risk conditions and in wound complication as defined previously, ABP prolongation showed limited efficacy (RR:1.97; 95% CI: 1.21-3.22 and 9.31; 95% CI: 5.90-14.68 respectively).

CONCLUSIONS

The subjects submitted to complicated, repeated, long lasting craniotomies, especially if experiencing postoperative deterioration, display the higher risk of SSIs, as a final life-threatening complication. In order to reduce the SSI rate, further studies should address to design tailored prophylaxis protocols for each high risk situation as hereby defined; the wound complications deserve an increased microbiological surveillance, focusing the attention on the timing and source of infections.