Early prediction of infection after craniotomy for brain tumours

Incidence and Risk Factors of Surgical Site Infection After Cranial Surgery for Patients with Brain Tumors: A Systematic Review and Meta-analysis

BACKGROUND

Surgical site infections after craniotomy (SSI-CRANs) are a serious adverse event given the proximity of the wound to the central nervous system. SSI-CRANs are associated with substantial patient morbidity and mortality. Despite the importance and recognition of this event in other surgical fields, there is a paucity of evidence in the neurosurgical literature devoted to SSI-CRAN specifically in patients after brain tumor surgery.

METHODS

Systematic searches of Medline, Embase, and Cochrane Central were undertaken. The primary outcome was the incidence of SSI-CRAN at 30 and 90 days. Secondary outcomes were risk factors for SSI-CRAN.

RESULTS

Thirty-seven studies reporting 91,907 patients with brain tumors who underwent cranial surgery were included in the meta-analysis. Pooled incidence of SSI-CRAN at 30 and 90 days was 4.03% (95% CI: 2.94%-5.28%, I2 = 97.3) and 6.17% (95% CI: 3.16%-10.07%, I2 = 97.3), respectively. Specifically, incidence of SSI-CRAN following surgery for posterior fossa tumors was the highest at 9.67% (95% CI: 5.98%-14.09%, I2 = 75.5). Overall pooled incidence of readmission within 30 days and reoperation due to SSI-CRAN were 13.9% (95% CI: 12.5%-15.5%, I2 = 0.0) and 16.3% (95% CI: 5.4%-31.3%, I2 = 72.9), respectively. Risk factors for SSI-CRAN included reintervention (risk ratio [RR] 1.58, 95% CI: 1.22-2.04, I2 = 0.0), previous radiotherapy (RR 1.69, 95% CI: 1.20-2.38, I2 = 0.0), longer duration of operation (mean difference 64.18, 95% CI: 3.96-124.40 minutes, I2 = 90.3) and cerebrospinal fluid (CSF) leaks (RR 14.26, 95% CI: 2.14-94.90, I2 = 73.2).

CONCLUSIONS

SSI-CRAN affects up to 1 in 14 patients with brain tumors. High-risk groups include those with reintervention, previous radiotherapy, longer duration of operation, and CSF leaks. Further prospective studies should focus on bundles of care that will reduce SSI-CRAN.

A data-driven medical knowledge discovery framework to predict the length of ICU stay for patients undergoing craniotomy based on electronic medical records

Craniotomy is an invasive operation with great trauma and many complications, and patients undergoing craniotomy should enter the ICU for monitoring and treatment. Based on electronic medical records (EMR), the discovery of high-risk multi-biomarkers rather than a single biomarker that may affect the length of ICU stay (LoICUS) can provide better decision-making or intervention suggestions for clinicians in ICU to reduce the high medical expenses of these patients and the medical burden as much as possible. The multi-biomarkers or medical decision rules can be discovered according to some interpretable predictive models, such as tree-based methods. Our study aimed to develop an interpretable framework based on real-world EMRs to predict the LoICUS and discover some high-risk medical rules of patients undergoing craniotomy. The EMR datasets of patients undergoing craniotomy in ICU were separated into preoperative and postoperative features. The paper proposes a framework called Rules-TabNet (RTN) based on the datasets. RTN is a rule-based classification model. High-risk medical rules can be discovered from RTN, and a risk analysis process is implemented to validate the rules discovered by RTN. The performance of the postoperative model was considerably better than that of the preoperative model. The postoperative RTN model had a better performance compared with the baseline model and achieved an accuracy of 0.76 and an AUC of 0.85 for the task. Twenty-four key decision rules that may have impact on the LoICUS of patients undergoing craniotomy are discovered and validated by our framework. The proposed postoperative RTN model in our framework can precisely predict whether the patients undergoing craniotomy are hospitalized for too long (more than 15 days) in the ICU. We also discovered and validated some key medical decision rules from our framework.

Central nervous system hemangioblastomas in the elderly (over 65 years): Clinical characteristics and outcome analysis

OBJECTIVES

Hemangioblastomas (HBs) in the elderly are very uncommon and have rarely been studied. This retrospective study aimed to identify clinical features, optimal treatment, surgical outcomes and long-term prognostic factors in these rare lesions.

PATIENTS AND METHODS

We performed a retrospective analysis of HBs patients over 65 years old who underwent surgery from 2008 to 2018 at our department. Clinical data was retrospectively reviewed and statistically analyzed.

RESULTS

Thirty-three elderly patients with a mean age of 68.76 years were included in this study. Cerebellum, brainstem, and spinal cord locations accounted for 72.7 %, 18.2 % and 9.1 %. Two patients (6.1 %) were diagnosed as von Hippel-Lindau (VHL) syndrome. After mean follow-up of 37.95 ± 22.12 months, clinical symptoms improved in 22 patients (67 %), unchanged in seven patients (21 %) and aggravated in 4 patients (12 %). Only 1(3 %) patient experienced local recurrence during follow-up. Univariate analysis showed tumor size (P = 0.044) and tumor characteristic (cystic or solid) (P = 0.034) were significantly related to long-term outcomes, while multiple logistic regression analysis depicted tumor characteristics were exclusively correlated with outcomes (P = 0.04).

CONCLUSIONS

Our study suggests elderly hemangioblastomas may be different from their younger counterparts in that they often display solid configuration with large size and include more cerebellar tumors. HBs should be included in the differential diagnosis of elderly patients presenting with cerebellar mass. Despite many challenges involved, surgical removal of HBs in this age group is a safe procedure with acceptable risks. They may do not require as frequent follow-up as younger counterparts due to the low associations with VHL disease and tumor recurrence rate.

Predictors of Surgical Site Infection After Nonemergent Craniotomy: A Nationwide Readmission Database Analysis

OBJECTIVE

Surgical site infections (SSIs) carry significant patient morbidity and mortality and are a major source of readmissions after craniotomy. Because of their deleterious effects on health care outcomes and costs, identifying modifiable risk factors holds tremendous value. However, because SSIs after craniotomy are rare and most existing data comprise single-institution studies with small sample sizes, many are likely underpowered to discern for such factors. The objective of this study was to use a large hetereogenous patient sample to determine SSI incidence after nonemergent craniotomy and identify factors associated with readmission and subsequent need for wound washout.

METHODS

We used the 2010-2014 Nationwide Readmissions Database cohorts to discern for factors predictive of SSI and washout.

RESULTS

We identified 93,920 nonemergent craniotomies. There were 2079 cases of SSI (2.2%) and 835 reoperations for washout (0.89%) within 30 days of index admission and there were 2761 cases of SSI (3.6%) and 1220 reoperations for washout (1.58%) within 90 days. Several factors were predictive of SSI in multivariate analysis, including tumor operations, external ventricular drain (EVD), age, length of stay, diabetes, discharge to an intermediate-care facility, insurance type, and hospital bed size. Many of these factors were similarly implicated in reoperation for washout.

CONCLUSIONS

SSI incidence in neurosurgery is low and most readmissions occur within 30 days. Several factors predicted SSI after craniotomy, including operations for tumor, younger age, hospitalization length, diabetes, discharge to institutional care, larger hospital bed size, Medicaid insurance, and presence of an EVD. Diabetes and EVD placement may represent modifiable factors that could be explored in subsequent prospective studies for their associations with cranial SSIs.

Infections in patients undergoing craniotomy: risk factors associated with post-craniotomy meningitis

OBJECT The authors performed a prospective study to define the prevalence and microbiological characteristics of infections in patients undergoing craniotomy and to clarify the risk factors for post-craniotomy meningitis. METHODS Patients older than 18 years who underwent nonstereotactic craniotomies between January 2006 and December 2008 were included. Demographic, clinical, laboratory, and microbiological data were systemically recorded. Patient characteristics, craniotomy type, and pre- and postoperative variables were evaluated as risk factors for meningitis RESULTS Three hundred thirty-four procedures were analyzed (65.6% involving male patients). Traumatic brain injury was the most common reason for craniotomy. Almost 40% of the patients developed at least 1 infection. Ventilator-associated pneumonia (VAP) was the most common infection recorded (22.5%) and Acinetobacter spp. were isolated in 44% of the cases. Meningitis was encountered in 16 procedures (4.8%), and CSF cultures were positive for microbial growth in 100% of these cases. Gram-negative pathogens (Acinetobacter spp., Klebsiella spp., Pseudomonas aeruginosa, Enterobacter cloaceae, Proteus mirabilis) represented 88% of the pathogens. Acinetobacter and Klebsiella spp. demonstrated a high percentage of resistance in several antibiotic classes. In multivariate analysis, the risk for meningitis was independently associated with perioperative steroid use (OR 11.55, p = 0.005), CSF leak (OR 48.03, p < 0.001), and ventricular drainage (OR 70.52, p < 0.001). CONCLUSIONS Device-related postoperative communication between the CSF and the environment, CSF leak, and perioperative steroid use were defined as risk factors for meningitis in this study. Ventilator-associated pneumonia was the most common infection overall. The offending pathogens presented a high level of resistance to several antibiotics.

Risk factors and outcomes associated with surgical site infections after craniotomy or craniectomy

OBJECT

Many studies that have evaluated surgical site infections (SSIs) after craniotomy or craniectomy (CRANI) did not use robust methods to assess risk factors for SSIs or outcomes associated with SSIs. The authors conducted the current study to identify risk factors for SSIs after CRANI procedures and to evaluate outcomes attributed to SSIs.

METHODS

The authors performed a nested case-control study of patients undergoing CRANI procedures between 2006 and 2010 at the University of Iowa Hospitals and Clinics. They identified 104 patients with SSIs and selected 312 controls. They collected data from medical records and used multivariate analyses to identify risk factors and outcomes associated with SSIs.

RESULTS

Thirty-two percent of SSIs were caused by Staphylococcus aureus, 88% were deep incisional or organ space infections, and 70% were identified after discharge. Preoperative length of stay (LOS) ≥ 1 day was the only significant patient-related factor in the preoperative model (OR 2.1 [95% CI 1.2-3.4]) and in the overall model (OR 1.9 [95% CI 1.1-3.3]). Procedure-related risk factors that were significant in the overall model included Gliadel wafer use (OR 6.7 [95% CI 2.5-18.2]) and postoperative CSF leak (OR 3.5 [95% CI 1.4-8.5]). The preoperative SSI risk index, including body mass index, previous brain operation, chemotherapy on admission, preoperative LOS, procedure reason, and preoperative glucose level, had better predictive efficacy (c-statistic = 0.664) than the National Healthcare Safety Network risk index (c-statistic = 0.547; p = 0.004). Surgical site infections were associated with increased LOS during the initial hospitalizations (average increase of 50%) or readmissions (average increase of 100%) and with an increased risk of readmissions (OR 7.7 [95% CI 4.0-14.9]), reoperations (OR 36 [95% CI 14.9-87]), and death (OR 3.4 [95% CI 1.5-7.4]).

CONCLUSIONS

Surgeons were able to prospectively assess a patient's risk of SSI based on preoperative risk factors and they could modify some processes of care to lower the risk of SSI. Surgical site infections substantially worsened patients' outcomes. Preventing SSIs after CRANI could improve patient outcomes and decrease health care utilization.

Clinical significance of positive cranial bone flap cultures and associated risk of surgical site infection after craniotomies or craniectomies

OBJECT

The risk of surgical site infection (SSI) after craniotomies or craniectomies in patients in whom contaminated bone flaps have been reimplanted has not been determined. The objectives of this study were to identify the prevalence of bone flaps with positive cultures--especially those contaminated with Propionibacterium acnes--to assess the risk of SSI after reimplanting (either during the initial operation or subsequently) bone flaps with positive cultures, and to identify risk factors for SSI following the initial craniotomies or craniectomies.

METHODS

The authors conducted a retrospective review of cases in which patients underwent craniotomy/craniectomy procedures between January and October 2007 in the neurosurgery department at the University of Iowa Hospitals and Clinics. They also reviewed processes and procedures and did pulsed field gel electrophoresis of P. acnes isolates to look for a common source of contamination. They then conducted a prospective cohort study that included all patients who underwent craniotomy/craniectomy procedures between November 2007 and November 2008 and met the study criteria. For the cohort study, the authors obtained cultures from each patient's bone flap during the craniotomy/craniectomy procedures. Data about potential risk factors were collected by circulating nurses during the procedures or by a research assistant who reviewed medical records after the procedures. An infection preventionist independently identified SSIs through routine surveillance using the Centers for Disease Control and Prevention's definitions. Univariate and bivariate analyses were performed to determine the association between SSI and potential risk factors.

RESULTS

The retrospective review did not identify specific breaks in aseptic technique or a common source of P. acnes. Three hundred seventy-three patients underwent 393 craniotomy/craniectomy procedures during the cohort study period, of which 377 procedures met the study criteria. Fifty percent of the bone flaps were contaminated by microorganisms, primarily skin flora such as P. acnes, coagulase-negative staphylococci, and Staphylococcus aureus. Reimplanting bone flaps that had positive culture results did not increase the risk of infection after the initial craniotomy/craniectomy procedures and the subsequent cranioplasty procedures (p = 0.80). Allowing the skin antiseptic to dry before the procedures (p = 0.04, OR 0.26) was associated with lower risk of SSIs. Female sex (p = 0.02, OR = 3.49) was associated with an increased risk of SSIs; Gliadel wafer implants (p = 0.001, OR = 8.38) were associated with an increased risk of SSIs after procedures to treat tumors.

CONCLUSIONS

Operative factors such as the way the skin is prepared before the incision rather than the skin flora contaminants on the bone flaps may play an important role in the pathogenesis of SSIs after craniotomy/craniectomy. Gliadel wafers significantly increased the risk of SSI after procedures to treat tumors.

Absence of an association between glucose levels and surgical site infections in patients undergoing craniotomies for brain tumors

Object

In select patient populations, hyperglycemia has been shown to increase the risk of surgical site infection (SSI), whereas stringent glucose control has improved outcomes. To date, no study has focused on whether SSIs in patients with brain tumors undergoing resection are associated with hyperglycemia.

Methods

The authors performed a retrospective chart review of patients who underwent a craniotomy after receiving a diagnosis of brain tumor. From 2001 to 2008, 2485 patients underwent a craniotomy for tumor resection at the Brain Tumor & Neuro-Oncology Center at the Cleveland Clinic. Fifty-seven of these patients (2.3%) developed SSIs postoperatively. A matched case-control study design was used, with 57 patients who developed SSIs after craniotomy (cases) matched with 57 patients who did not develop SSIs (controls). The results were analyzed using both univariate and multivariate conditional logistic regression.

Results

Glucose level was not a significant factor in postoperative SSI (p = 0.83) after adjusting for duration of surgery and adherence to antibiotic prophylaxis. However, duration of surgery was significantly associated with postoperative SSI (p = 0.047).

Conclusions

For patients who undergo craniotomy for definitive resection of a brain tumor, duration of surgery described more variation in the model to predict SSI than blood glucose levels.