A survey of possible etiologic agents in postoperative craniotomy infections

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.

Association of predictive factors and neurosurgical postoperative infections: A retrospective analysis

OBJECTIVE

To identify the factors that predispose neurosurgical patients to surgical site infections (SSI) as well as assess the risk factors attached to infection by a specific microorganism.

METHODOLOGY

A retrospective case-control study was conducted at University College of Medical Sciences and G.T.B. Hospital, Delhi. Adult patients (>18 years) undergoing a neurosurgical procedure with a diagnosis of SSI in the year 2021 having a minimum follow up of 30 days postoperatively or until death if they survived less than 30 days were included. Statistical analysis was performed using the SPSS 16 software with level of significance at 0.05.

RESULTS

An incidence of 3.15% was observed at our center. Mean age of the study population was 39.2 ± 13.07 years (range 22-70 years) with a male: female ratio of 3:1. Having an underlying infection (p = 0.024), ASA score> 2 (p = 0.041), duration of surgery> 4 h (p = 0.025), diabetes (p = 0.027) and preoperative stay at the hospital (p = 0.036) were found to be statistically significant risk factors in the prediction of SSI in neurosurgical patients which were utilised to create a regression model with an accuracy of 70% and AUC of 0.833. Deep infections were found to have a significant association with positive culture on the collected samples (p = 0.035).

CONCLUSIONS

This study is a starting point to identify which factors could predict the presence of a particular organism isolated from the site of infection in neurosurgical patients, thereby minimizing AMR.

Surgical Antimicrobial Prophylaxis in Neonates and Children Undergoing Neurosurgery: A RAND/UCLA Appropriateness Method Consensus Study

Pediatric neurosurgery is a highly specialized branch of surgery in which surgical site infections (SSIs) are potentially serious complications that can also adversely affect a good surgical outcome, compromising functional recovery and, in some cases, even putting the patient’s life at risk. The main aim of this consensus document is to provide clinicians with a series of recommendations on antimicrobial prophylaxis for neonates and children undergoing neurosurgery. The following scenarios were considered: (1) craniotomy or cranial/cranio-facial approach to craniosynostosis; (2) neurosurgery with a trans-nasal-trans-sphenoidal approach; (3) non-penetrating head injuries; (4) penetrating head fracture; (5) spinal surgery (extradural and intradural); (6) shunt surgery or neuroendoscopy; (7) neuroendovascular procedures. Patients undergoing neurosurgery often undergo peri-operative antibiotic prophylaxis, with different schedules, not always supported by scientific evidence. This consensus provides clear and shared indications, based on the most updated literature. This work has been made possible by the multidisciplinary contribution of experts belonging to the most important Italian scientific societies, and represents, in our opinion, the most complete and up-to-date collection of recommendations on the behavior to be held in the peri-operative setting in this type of intervention, in order to guide physicians in the management of the patient, standardize approaches and avoid abuse and misuse of antibiotics.

A Novel Approach for Responsive Neural Stimulator Implantation With Infraclavicular Placement of the Internal Pulse Generator

INTRODUCTION

The Responsive Neurostimulation System (RNS, Neuropace, Mountain View, California) has been proven to be effective at reducing seizures in patients with partial-onset epilepsy. The system incorporates a skull-mounted neurostimulator that requires a cranial incision for replacement. Although integral to the functioning of the system, in some circumstances, such as in the setting of infection, this can be disadvantageous. At present, there are no alternatives to cranial implantation of the RNS System.

METHODS

We describe a novel procedure enabling implantation of the neurostimulator within the chest wall, using components from a peripheral nerve stimulator. In a patient who achieved complete seizure freedom with the use of the RNS System, distant site implantation provided a viable means of continuing therapy in a setting where device explantation would have otherwise been inevitable as a result of cranial infection. We present continuous electrocorticographic data recorded from the device documenting the performance of the system with the subclavicular neurostimulator.

RESULTS

Band pass detection rates increased by 50%, while line length detection rates decreased by 50%. The number of detections decreased from 1046 to 846, with a resultant decrease in stimulations. Although there was some compromise of function due to the elevated noise floor, more than 2 yr following the procedure the patient remains free of seizures and infection.

CONCLUSION

The salvage procedure we describe offered an alternative therapeutic option in a patient with a complicated cranial wound issue, using heterogeneous components with marginal compromises in device functionality and no sacrifice in patient outcome.

Risk factors of neurosurgical site infection after craniotomy: A systematic review and meta-analysis

BACKGROUND

Neurosurgical site infection (SSI) is a complication related to craniotomy, which may lead to severe morbidity and higher hospital costs during the postoperative period.

METHODS

Retrospective cohorts, case-control studies, or prospective investigations addressing risk factors of SSI updated until January 2017 were systematically searched in 2 databases (PubMed and Embase). The Newcastle-Ottawa Scale was used to evaluate quality of the included studies, heterogeneity was assessed by I² tests, and a funnel plot and Egger test were used for the evaluation of publication bias.

RESULTS

There were 26 studies in total enrolled in this review. The results showed that the risk factors which had relation with SSI were other infection (odds ratio [OR], 5.42; 95% confidence interval [CI], 2.8-10.49), number of operations (>1) (OR, 2.352; 95% CI, 1.142-4.847), cerebrospinal fluid (CSF) leak (OR, 7.817; 95% CI, 2.573-23.751), CSF drainage (OR, 2.55; 95% CI, 1.58-4.11), duration of operation (>4 hours) (as for retrospective cohort studies) (OR, 1.766; 95% CI, 1.110-2.809), venous sinus entry (OR, 4.015; 95% CI, 1.468-10.982), American Society of Anesthesiologists score (>2) (OR, 1.398; 95% CI, 1.098-1.78), sex (male) (as for prospective investigations) (OR, 1.474; 95% CI, 1.013-2.145), and surgical reasons (nontraumatic) (OR, 2.137; 95% CI, 1.106-4.129).

CONCLUSIONS

According to the current analysis, all the factors mentioned were the risk factors for SSI after craniotomy. Patients with these risk factors should be paid more attention to prevent SSI. More evidence provided by high-quality studies is still needed to further investigate the risk factors of SSI.

The Role of Antibiotic Prophylaxis in Clean Neurosurgery

OBJECTIVE

To investigate the efficacy of antibiotic prophylaxis (AP) and the risk factors for postoperative infections in clean neurosurgery.

METHODS

Data were retrospectively collected on all patients who had undergone clean neurosurgical operation at our institution between January 2009 and December 2014. From January 2009 until October 2011, AP was administered to every clean neurosurgical patient. From November 2011 to December 2014, no AP (n-AP) was prescribed for all clean neurosurgical operations. The efficacy of AP and independent risk factors for infection were studied.

RESULTS

A total of 808 clean neurosurgical cases were included. The AP group comprised 360 surgical cases, including 29 meningitis cases and 2 cases of incision infections, whereas the n-AP group consisted of 448 surgical cases, including 35 meningitis cases and 4 cases of incision infections (P = 0.848). Microorganisms were identified in 7 of 29 cases in the AP group compared with their identification in 22 of 35 cases in the n-AP group (P = 0.002). The percentage of patients with multidrug-resistant bacterial meningitis in the AP group was 57.1% compared with 13.6% in the n-AP group (P = 0.038). The risk factors for postoperative infection were cerebrospinal fluid leakage (odds ratio, 27.8; 95% confidence interval, 9.38-28.55) and surgery time (odds ratio, 1.12; 95% confidence interval, 1.02-1.22).

CONCLUSIONS

Our results show that in our data set, AP had no preventive effect on postoperative infections in clean neurosurgery. In addition, AP appeared to decrease the positive bacterial culture rate and to promote the emergence of multidrug-resistant bacteria. Cerebrospinal fluid leakage and surgery time were the risk factors for postoperative infection.

Risk factors for meningitis after craniotomy in patients with subarachnoid hemorrhage due to anterior circulation aneurysms rupture

OBJECTIVES

Postoperative meningitis is a serious complication occurring after neurosurgical interventions. However, few investigations have focused specifically on the risk factors that predispose patients to meningitis after major craniotomy. This study identified the risk factors for postoperative meningitis after neurovascular surgery, and investigated the relationship between postoperative meningitis and clinical outcome.

PATIENTS AND METHODS

A total of 148 consecutive patients with subarachnoid hemorrhage (SAH) who underwent clipping surgery through a pterional approach within 72 h between January 2007 and September 2011 were retrospectively analyzed. The treatment strategy of our hospital for patients with SAH was based on the findings of digital subtraction angiography in the acute phase. Coil embolization was firstly considered, and clipping through craniotomy if indicated was performed as soon as possible. Prophylactic antibiotics were administered before beginning craniotomy and for at least 3 days after. Hydrocortisone was used to prevent hyponatremia if allowed by the medical condition of the patient. Intrathecal administration of nicardipine hydrochloride was given if required for vasospasm treatment. Meningitis was clinically diagnosed from the blood samplings and cerebrospinal fluid (CSF) examinations. Data were collected from the electronic and paper charts. The status of modified Rankin scale (mRS) 0-2 at discharge was defined as favorable outcome.

RESULTS

A total of 14 patients (9.5%) had meningitis during this study period. Symptomatic vasospasm was detected in 33 patients (22.3%), and 12 patients (8.1%) had permanent neurological deficits caused by vasospasm. Overall, 109 patients (73.6%) had favorable outcome. The longer duration of drainage placement, presence of CSF leakage, and intrathecal administration of vasodilatory agent showed significantly higher incidence of postoperative meningitis in univariate analysis (p=0.0093, 0.0017, and 0.0090, respectively). The proportion of favorable outcome patients at discharge (mRS 0-2) was significantly lower in patients with postoperative meningitis (35.7%) than in patients without it (77.6%) (p=0.0004). The duration of in-hospital stay was significantly longer in patients with postoperative meningitis (median 58.5, range 28-115 days) than in patients without it (median 38.5, range 19-149 days) (p<0.001). Multivariate logistic regression analysis showed that only presence of CSF leakage was associated with postoperative meningitis (p=0.0299).

CONCLUSION

Meningitis after surgery is still a serious complication that requires preventative intervention. The clinical outcome of patients with postoperative meningitis after neurovascular surgery is not still satisfactory.

The incidence and risk factors of meningitis after major craniotomy in China: a retrospective cohort study

Background

Meningitis after neurosurgery can result in severe morbidity and high mortality. Incidence varies among regions and limited data are focused on meningitis after major craniotomy.

Aim

This retrospective cohort study aimed to determine the incidence, risk factors and microbiological spectrum of postcraniotomy meningitis in a large clinical center of Neurosurgery in China.

Methods

Patients who underwent neurosurgeries at the Department of Neurosurgery in Huashan Hospital, the largest neurosurgery center in Asia and the Pacific, between 1^stJanuary and 31^st December, 2008 were selected. Individuals with only shunts, burr holes, stereotactic surgery, transsphenoidal or spinal surgery were excluded. The complete medical records of each case were reviewed, and data on risk factors were extracted and evaluated for meningitis.

Results

A total of 65 meningitides were identified among 755 cases in the study, with an incidence of 8.60%. The risk of meningitis was increased by the presence of diabetes mellitus (odds ratio [OR], 6.27; P = 0.009), the use of external ventricular drainage (OR, 4.30; P = 0.003) and the use of lumbar drainage (OR, 17.23; P<0.001). The isolated microorganisms included Acinetobacter baumannii, Enterococcus sp, Streptococcus intermedius and Klebsiella pneumonia.

Conclusions

Meningitis remains an important source of morbidity and mortality after major craniotomy. Diabetic patients or those with cerebral spinal fluid shunts carry significant high risk of infection. Thus, identification of the risk factors as soon as possible will help physicians to improve patient care.

Antibiotic prophylaxis in craniotomy: a review

The effectiveness of antibiotic prophylaxis (AP) in craniotomies has been clarified through the accumulation of evidence and increased antibiotic knowledge. This paper focuses on the use of AP in craniotomies during different historical periods and collects highly relevant evidence on this issue. This review surveys different AP guidelines and explains why cefazolin was selected by most guidelines. Recent prominent topics, including strategies to update and implement guidelines and antibiotic efficacy in postoperative meningitis and surveillance and decolonization therapies for methicillin-resistant Staphylococcus aureus, are discussed.

Complex wound-healing problems in neurosurgical patients: risk factors, grading and treatment strategy

BACKGROUND

Wound-healing problems in the neurosurgical patient can be particularly bothersome, owing to various specific risk factors involved. These may vary from simple wound dehiscence to complex multi-layer defects with cerebrospinal fluid (CSF) leakage and contamination. The latter is quite rare in practice and requires an individually titrated reconstruction strategy. The objective is to retrospectively analyze neurosurgical patients with complex, recalcitrant wound-healing problems we had treated in our department, attempt to develop a grading system based on the risk factors specific to our specialty and adapt a surgical reconstruction algorithm.

METHODS

During an 11-year period, 49 patients were identified to have had complex, recalcitrant wound-healing problems involving the cranial vault (n = 43) and the skull base (n = 6) that required an adapted surgical wound-management strategy. The etiologies of wound healing problems were aftermaths of surgical treatment of: (1) brain tumors (nine cases), (2) aneurysm clipping (ten cases), (3) trauma (27 patients), and (4) congenital malformations (three patients). Local rotational advancement flaps were performed in 18 patients and free microvascular tissue transfer was performed in 37 cases.

RESULTS

Major risk factors leading to recalcitrant wound healing problems in the presented group were: prolonged angiographic interventions (20%), ongoing chemotherapy or radiotherapy (47%), prolonged cortisone application (51%), CSF leak (76%) and, above all, multiple failed attempts at wound closure (94%). Stable long-term wound healing was achieved in all patients using vascularized tissue coverage. A ternary grading system was developed based on various risk factors in the presented cohort. Accordingly, the algorithm for reconstruction in neurosurgical patients was adapted.

CONCLUSIONS

Primary disease, treatment history, and distorted anatomical structures are major concerns in the management of complex wound-healing problems in neurosurgical patients. The higher the risk factors involved, the more complex is the surgical strategy. Free microvascular tissue transfer offers stable long-term results in recalcitrant cases. However, this may be indicated only in patients with a good prognosis of the underlying disease.

Central nervous system infection in the pediatric population

Infection of the central nervous system is a life-threatening condition in the pediatric population. Almost all agents can cause infection within the central nervous system and the extent of infection ranges from diffuse involvement of the meninges, brain, or the spinal cord to localized involvement presenting as a space-occupying lesion. Modern imaging techniques define the anatomic region infected, the evolution of the disease, and help in better management of these patients. Acute bacterial meningitis remains a major cause of mortality and long-term neurological disability. Fortunately, the incidence of infection after clean craniotomy is < 5%, but it leads to significant morbidity as well as fiscal loss. The most significant causative factor in postcraniotomy infections is postoperative CSF leak. Cerebral abscess related to organic congenital heart disease is one of the leading causes of morbidity and mortality in the pediatric population. The administration of prophylactic antibiotics is indicated for contaminated and clean-contaminated wounds.

Topical antibiotics and neurosurgery: Have we forgotten to study it?

BACKGROUND

For neurosurgery, the last decades have been a time of incredible improvement in areas such as imaging, microscopy, endoscopy, stereotactic guidance, navigation, radiosurgery and endovascular techniques. However, the efficacy of topical antibiotic prophylaxis in neurological operations remains to be established by neurosurgeons.

METHODS

The authors did an historical review of the literature regarding the utilization of topical antibiotic prophylaxis in neurological operations. The Pub Med database of the U.S. National Library of Medicine / National Institutes of Health was utilized as the primary source of the literature. The authors performed the search by using the following Mesh terms: "neurosurgery" or "neurosurgical procedures" and "administration, topical" and "antibiotic prophylaxis"; "neurosurgery" or "neurosurgical procedures" and "administration, topical" and "antibacterial agents."

RESULTS

In the last 70 years, we have poorly studied the use of topical antibiotics in neurosurgery. All the papers reported were Class III evidence.

CONCLUSION

To the best of our knowledge, there is no publication that provided Class I or II evidence about topical antibiotic prophylaxis in neurosurgery.

Risk factors for neurosurgical site infections: an 18-month prospective survey

OBJECT

The purpose of this study was to determine the incidence rate and risk factors of surgical site infections (SSIs) in neurosurgery for any type of surgery and any American Society of Anesthesiologists class.

METHODS

The authors undertook an exhaustive 18-month prospective survey including patients who underwent neurosurgery. In particular, a 30-day follow-up was completed in patients whose surgery did not involve placement of a prosthesis or implant, and 1-year follow-up was completed for patients who underwent surgery to place a prosthesis or implant. The Centers for Disease Control definition of SSI was used. Univariate and multivariate analyses were conducted; all dependent variables found in univariate analysis were entered in the multiple regression model. A stepwise multiple logistic regression method was used.

RESULTS

Of the 844 patients studied, 35 SSIs were diagnosed, yielding an incidence rate of 4.1% (95% confidence interval 3.6-4.5). Independent predictive risk factors for infection were cerebrospinal fluid leakage, external shunt, Altemeier class, and further neurosurgery. A lack of antibiotic prophylaxis was not found to be a risk factor.

CONCLUSIONS

Infection risk factors occur mainly during the postoperative period.

Efficacy of Prophylactic Antibiotics Against Meningitis after Craniotomy: A Meta-Analysis

OBJECTIVE

Although prophylactic antibiotics have been shown by randomized clinical trials (RCTs) to help prevent deep infection after craniotomies, recent reports have suggested that antibiotics are not effective in preventing postcraniotomy meningitis.

METHODS

Data on meningitis as an end point from RCTs on prophylactic antibiotics for craniotomies were pooled in a random-effects meta-analysis.

RESULTS

Six prospective randomized trials or trial subgroups enrolling 1729 patients or operations were identified. Antibiotics reduced postoperative infection rates in five of the six RCTs; no trial individually showed a statistically significant benefit from antibiotics. The pooled odds ratio for meningitis with antibiotic treatment in the six RCTs was 0.43 (95% confidence interval, 0.20–0.92; P = 0.03). Subgroup analyses showed no detectable difference in antibiotic efficacy if antibiotics, with or without gram- negative coverage, were used or if the trial was single or double blinded. A sensitivity analysis showed modest dependence of the results of the analysis on the specific definition of postoperative meningitis used in interpreting trial results.

CONCLUSION

Prophylactic antibiotics administered before craniotomy reduce rates of postoperative meningitis by approximately one-half, a statistically and clinically significant benefit.

Risk factors associated with postcraniotomy meningitis

OBJECTIVE

The authors conducted a retrospective cohort study to determine the incidence, bacteriological features, and risk factors for postcraniotomy meningitis.

METHODS

Patients older than 18 years who underwent nonstereotactic craniotomies between January 1996 and March 2000 and who survived for more than 7 days were included. Operations for placement of burr holes and shunts were excluded. Records of the first 30 postoperative days were abstracted. Host factors, types of craniotomy, and pre- and postoperative variables were evaluated as risk factors for meningitis

RESULTS

Among 453 patients, there were 25 cases of meningitis. Eight out of 12 culture-positive cases were the result of gram-positive cocci. Four hundred twenty (92%) patients received antibiotic prophylaxis, most commonly a first-generation cephalosporin. In multivariate analysis, the risk of meningitis was increased by surgery that entered a sinus (odds ratio [OR], 4.49; P = 0.018), an increase in the American Society of Anesthesiologists score (OR, 1.72; P = 0.023), and increases in the number of days of external ventricular drainage (OR, 1.21; P = 0.049) and intracranial pressure monitoring (OR, 1.24; P = 0.002).

CONCLUSION

Access of upper airway bacteria to the surgical wound, host factors as expressed by the American Society of Anesthesiologists score, and duration of device-related postoperative communication of the cerebrospinal fluid and the environment are major risk factors for postoperative meningitis after craniotomy.

Risk Factors for Adult Nosocomial Meningitis After Craniotomy Roleof Antibiotic Prophylaxis

OBJECTIVE

To evaluate incidence and risk factors of postoperative meningitis, with special emphasis on antibiotic prophylaxis, in a series of 6243 consecutive craniotomies.

METHODS

Meningitis was individualized from a prospective surveillance database of surgical site infections after craniotomy. Ventriculitis related to external ventricular drainage or cerebrospinal fluid shunt were excluded. From May 1997 until March 1999, no antibiotic prophylaxis was prescribed for scheduled, clean, lasting less than 4 hours craniotomies, whereas emergency, clean-contaminated, or long-lasting craniotomies received cloxacillin or amoxicillin-clavulanate. From April 1999 until December 2003, prophylaxis was given to every craniotomy. Independent risk factors for meningitis were studied by a multivariate analysis. Efficacy of antibiotic prophylaxis in preventing meningitis was studied as well as consequences on bacterial flora.

RESULTS

The overall meningitis rate was 1.52%. Independent risk factors were cerebrospinal fluid leakage, concomitant incision infection, male sex, and surgical duration. Antibiotic prophylaxis reduced incision infections from 8.8% down to 4.6% (P < 0.0001) but did not prevent meningitis: 1.63% in patients without antibiotic prophylaxis and 1.50% in those who received prophylaxis. Bacteria responsible for meningitis were mainly noncutaneous in patients receiving antibiotics and cutaneous in patients without prophylaxis. In the former, microorganisms tended to be less susceptible to the prophylactic antibiotics administered. Mortality rate was higher in meningitis caused by noncutaneous bacteria as compared with those caused by cutaneous microorganisms.

CONCLUSION

Perioperative antibiotic prophylaxis, although clearly effective for the prevention of incision infections, does not prevent meningitis and tends to select prophylaxis resistant microorganisms.

Risk factors for surgical site infections in neurosurgery patients with antibiotic prophylaxis

BACKGROUND

This prospective study aimed to determine the spectrum and the main risk factors of surgical site infection (SSI) after neurosurgical procedures in our clinic.

METHODS

Consecutive patients undergoing neurosurgery between November 1, 2001, and November 1, 2002, were recruited for the study. All patients were followed for a minimum of 2 weeks postoperatively and all SSIs were recorded. The complete medical records of each case were reviewed, and data on 14 possible risk factors were extracted. Statistical analyses were performed to identify the risk factors for SSIs.

RESULTS

A total of 31 postoperative SSIs were identified among 503 cases included in the study, with a resulting overall infection rate of 6.2%. The risk of SSI was increased by age (odds ratio [OR], 1.1; 95% confidence interval [CI], 1.0-1.1; P = .039), operation type such as "shunt operations" (OR, 670.4; 95% CI, 2.6-171123.1; P = .021), presence of foreign body (OR, 141.0; 95% CI, 2.5-7925.9; P = .016), presence of diabetes mellitus (OR, 24.3; 95% CI, 2.1-284.9; P = .011), and intracranial pressure monitoring (OR, 4878.9; 95% CI, 23.8-1001229; P = .002). The predominantly isolated microorganisms in patients with SSIs were Staphylococcus aureus (22 [71.0%]), Acinetobacter baumanii (5 [16.1%]), and Staphylococcus epidermidis (4 [12.9%]).

CONCLUSIONS

SSIs remain an important problem in neurosurgery. Identification of the risk factors for SSI will help physicians to improve patient care and may decrease mortality, morbidity, and health care costs of neurosurgery patients.

L'infection postopératoire après craniotomie chez l'adulte

OBJECTIVE

The aim of this study was to determine the risk factors for postoperative infection after craniotomy, a threat for the vital prognosis, in order to define specific prevention measures.

METHOD AND PATIENTS

An open prospective study was made on all adult patients undergoing craniotomy and followed 30 days postoperatively. The infections were defined according to CDCA criteria. The parameters studied were: age, sex, ASA and Glasgow scores, neurosurgical history, the type, the moment and the surface of shaving, antibioprophylaxis, and the type and duration of surgery as well as its emergency level.

RESULTS

One hundred and seventy patients were included. Thirty presented with an infection (17.6%), nine with a skull infection, 13 with meningitis, three with empyema, and two with osteitis. The risk factors identified thanks to a univariate analysis were the emergency level of surgery (P < 0.01), duration of surgery >200 min, and duration of stay in ICU >72 h (P < 0.02).

Preservation of bone flaps in patients with postcraniotomy infections

OBJECT

Management of postcraniotomy wound infections has traditionally consisted of operative debridement and removal of devitalized bone flaps followed by delayed cranioplasty. The authors report the highly favorable results of a prospective study in which postcraniotomy wound infections were managed with surgical debridement to preserve the bone flaps and avoid cranioplasty.

METHODS

Since 1990, 13 patients with postcraniotomy wound infections have been prospectively treated with open surgical debridement and replacement of the bone flap. All patients received a full course of systemic antibiotic agents based on the determination of the bacterial culture and antibiotic sensitivity. Notable risk factors for infection included prior craniotomies, radiotherapy, and skull base procedures. The mean long-term follow-up period was 35 +/- 20 months. In all five patients who underwent craniotomies without complications, bone flap preservation was possible with full resolution of the infection and without the need for additional surgery. Among the eight patients with risk factors, bone preservation was possible in six patients, although two required minor wound revisions (without bone flap removal). Both patients who underwent craniofacial procedures required an additional procedure in which the bone flap was removed for recurrent infection (one after 2 months and the other after 29 months).

CONCLUSIONS

In patients with uncomplicated postcraniotomy infections, simple operative debridement is sufficient and it is not necessary to discard the bone flaps and perform cranioplasties. Even patients with risk factors such as prior surgery or radiotherapy can usually be treated using this strategy. Patients who undergo craniofacial surgeries involving the nasal sinuses are at higher risk and may require bone flap removal.

Concomitant use of computer image guidance, linear or sigmoid incisions after minimal shave, and liquid wound dressing with 2-octyl cyanoacrylate for tumor craniotomy or craniectomy: analysis of 225 consecutive surgical cases with antecedent historical control at one institution

OBJECTIVE

Recent neurosurgical literature reflects rapidly evolving, technically enhanced methods that promise to improve neurosurgical outcomes. We review our experience with computer image guidance, linear or sigmoid incisions after minimal shaving, and liquid wound dressing with 2-octyl cyanoacrylate (Dermabond; Ethicon, Inc., Somerville, NJ) for tumor craniotomy or craniectomy in our attempt to optimize craniotomy or craniectomy for tumor.

METHODS

After institutional review board approval, we retrospectively reviewed patients who underwent craniotomy or craniectomy for tumor with or without the combination of techniques specified above. A prior cohort of patients who underwent craniotomy or craniectomy with traditional techniques served as a retrospective basis of comparison. Analysis included in- and outpatient chart reviews, which included the operative notes, pathology reports, discharge summaries, outpatient office records, and intraoperative nursing records. Data were entered into a statistical spreadsheet for analysis and comparison.

RESULTS

A total of 225 consecutive patients underwent a combination of less invasive techniques from July 2000 through October 2001. These patients were matched with 225 patients in a standard neurosurgical cohort that included patients who underwent operations from July 1994 through July 2000. Age, tumor type, radiation, reoperation rate, tumor location, and extent of resection were comparable for both groups. The overall wound complication rate was significantly lower in the minimally invasive group when compared with the control cohort of patients (0.9% versus 6.2%; P = 0.0298), even for early follow-up (0.9% versus 3.5%; P = 0.0427). Pedicle flap design was a variable that was significantly associated with wound complication.

CONCLUSION

Modern neurosurgical techniques are beneficial for patients undergoing craniotomy or craniectomy for tumor and seem to be superior to standard techniques. Although the study is multifactorial and retrospective, this conclusion is further supported by the enhanced self-image patients have during the postoperative period.

Hospital-acquired meningitis in patients undergoing craniotomy: incidence, evolution, and risk factors

OBJECTIVES

To establish the incidence of postcraniotomy meningitis, identify etiologic agents, assess patients' medical progress in relation to both length of hospitalization and mortality, and analyze risk factors.

MATERIAL AND METHODS

This study was developed at Hospital São Paulo, a tertiary university hospital, between August 1995 and January 1998. We conducted a case-control trial, in which 50 pairs of patients were matched.

RESULTS

An 8.9%-postcraniotomy meningitis incidence was found. Gram-negative bacilli were the most common etiologic agents isolated. Mortality among the patients was 30%. Mean hospital stay for the patients was 42.9 +/- 22.1 days; for the controls, mean hospital stay was 19.0 +/- 11.4 days (P =.00001). Although several risk factors were identified by univariate analysis, including postoperative external ventricular shunt (OR = 2.92, CI 95% = 1.245-6.865, P =.014), remote site infection (OR = 2.85, CI 95% = 0.995-8.173, P =.051), and repeat operation (OR = 5.02, CI 95% = 1.569-16.066, P =.007), only repeat operation remained in the multivariate analysis model (OR = 3.68, CI 95% = 1.158-11.700, P =.027).

CONCLUSION

Postcraniotomy meningitis resulted in a high mortality rate and a longer hospital stay, with repeat operation identified among the risk factors.

Hyperbaric Oxygen Treatment of Postoperative Neurosurgical Infections

OBJECTIVE

To evaluate the clinical usefulness of hyperbaric oxygen (HBO) therapy for neurosurgical infections after craniotomy or laminectomy.

METHODS

The study involved review of medical records, office visits, and telephone contacts for 39 consecutive patients who were referred in 1996 to 2000. Infection control and healing without removal of bone flaps or foreign material, with a minimum of 6 months of follow-up monitoring, were considered to represent success.

RESULTS

Successful results were achieved for 27 of 36 patients, with a mean follow-up period of 27 months (range, 6–58 mo). One patient discontinued HBO therapy because of claustrophobia, and two could not be evaluated because of death resulting from tumor recurrence. In Group 1 (uncomplicated cranial wound infections), 12 of 15 patients achieved healing with retention of bone flaps. In Group 2 (complicated cranial wound infections, with risk factors such as malignancy, radiation injury, repeated surgery, or implants), all except one infection resolved; three of four bone flaps and three of six acrylic cranioplasties could be retained. In Group 3 (spinal wound infections), all infections resolved, five of seven without removal of fixation systems. There were no major side effects of HBO treatment.

CONCLUSION

HBO treatment is an alternative to standard surgical removal of infected bone flaps and is particularly useful in complex situations. It can improve outcomes, reduce the need for reoperations, and allow infection control without mandatory removal of foreign material. HBO therapy is a safe, powerful treatment for postoperative cranial and spinal wound infections, it seems cost-effective, and it should be included in the neurosurgical armamentarium.

Postoperative intracranial abscess--clinical aspects in the differential diagnosis to early recurrence of malignant glioma

Out of 2941 patients who received a clean, major craniotomy, 39 patients (1.3%) developed the complication of an intracranial deep infection, i.e. abscess or empyema. A total of 14 patients with a postoperative abscess were initially operated upon intracerebral malignant glioma (WHO III or IV) and could be compared to a matched group of patients with recurrent malignancy concerning clinical and radiological aspects. A statistically significant elevation of median values was seen for erythrocyte sedimentation rate (ESR), fibrinogen and body temperature in the study group. C-reactive protein (CRP) was not investigated in the control group and could not be compared, but it was elevated in all abscess patients when measured. CT-scan did not allow a safe differentiation between infection and recurrent glioma. Local signs like suppuration of the wound could be observed in 71% of patients with intracranial infection. Postoperative abscesses had been diagnosed in all cases within 3 months, whereas none of the early recurrences of intracerebral malignoma became symptomatic before 12 weeks after initial operation. Therefore, the course of time seems to be another important factor in this differential diagnosis.

Risk factors for neurosurgical site infections after craniotomy: a prospective multicenter study of 2944 patients. The French Study Group of Neurosurgical Infections, the SEHP, and the C-CLIN Paris-Nord. Service Epidémiologie Hygiène et Prévention

OBJECTIVE

To determine the incidence and risk factors of surgical site infections (SSIs) after craniotomy and to test the risk index score proposed by the National Nosocomial Infections Surveillance (NNIS) system, which, to our knowledge, has not been validated in neurosurgery to date.

METHODS

During a 15-month period, every adult patient undergoing craniotomy in 10 neurosurgical units was prospectively evaluated for development and risk factors of SSI. The follow-up period was at least 30 days. SSIs were defined according to the Center for Disease Control definitions. Incidence was calculated per patient. Multivariate analyses were conducted at first to include all significant risk factors of univariate analysis and then only those known preoperatively. Finally, the NNIS risk index was tested in this population.

RESULTS

Of a total of 2944 patients, 117 patients (4%) with SSIs were observed, including 30 with wound infections, 14 with bone flap osteitis, 56 with meningitis, and 17 with brain abscesses. Independent risk factors for SSIs were postoperative cerebrospinal fluid leakage (odds ratio, 145; 95% confidence interval, 72-293) and subsequent operation (odds ratio, 7; 95% confidence interval, 4-12). Independent predictive risk factors were emergency surgery, clean-contaminated and dirty surgery, an operative time longer than 4 hours, and recent neurosurgery. Absence of antibiotic prophylaxis was not a risk factor. The NNIS risk index was effective in identifying at-risk patients.

CONCLUSION

Independent risk factors for SSIs after craniotomy involve postoperative events. However, the NNIS risk index is effective in identifying at-risk patients.

The perioperative use of ceftriaxone as infection prophylaxis in neurosurgery

An open label study was conducted in the department of neurosurgery, Beijing Tiantan Hospital in China to determine the incidence of postoperative infections following the use of one or two doses of ceftriaxone administered perioperatively. A total of 343 patients, who required neurosurgery and had satisfied the inclusion criteria, was recruited during a 12 month study period. Of these 343 patients, there were 97 and 107 cases of malignant and benign tumours, respectively, 52 cases of aneurysm, 34 cases of arteriovenous malformation, and 53 other cases who underwent neurosurgery for drainage of sub-dural haematoma, relief of cerebral oedema and other indications. A total of 6 (1.75%) cases of postoperative infection was observed, of which 4 were found in the malignant tumour group, and 2 in the arteriovenous malformation group. All six patients were suffering from meningitis. During the 12 month period immediately prior to the present study, when postoperative penicillin and gentamicin was administered twice daily for 5-7 days as regular prophylaxis against infection, the incidence of postoperative infection was 7.2% in the same department managed by the same staff. Results of our present study suggest that one to two doses of ceftriaxone administered perioperatively are effective in reducing the rate of postoperative infections.

Intracranial suppuration: a modern decade of postoperative subdural empyema and epidural abscess

A retrospective study of subdural empyema and epidural abscess spanning 11 years and encompassing 41 patients was performed, demonstrating that the clinical characteristics of intracranial suppuration have changed over time. Sinusitis and otitis media, previously the predominant etiologies, were predisposing factors in only 29% of patients. A prior craniotomy had been performed in 66% of cases and was the most common risk factor for abscess development. The postoperative patients were subjected to detailed analysis. Patients who had undergone a prior craniotomy were notable for the following features: older age, lack of fever, evidence of wound infection, frequent false-negative computed tomographic scans, and a high percentage of Gram negative aerobic organisms or skin flora as pathogens. The population at highest risk for abscess development ranged from 50 to 60 years old, older than in previous series. Older age and an advanced degree of encephalopathy were indicative of a poor prognosis. Patients with subdural empyema had a worse prognosis as well. Hyponatremia was a frequent complicating factor. A much greater percentage of Gram-negative aerobic bacteria were isolated than in previous studies. Computed tomographic scans, half of which were performed with intravenous contrast material, were nondiagnostic in 30% of patients. The mortality rate was 18.5%, and delay in treatment correlated with increased risk of poor outcome. All patients were treated with a craniotomy. Repeated operations were required in three patients and were associated with the development of intraparenchymal abscess.

Operative sepsis in neurosurgery: a method of classifying surgical cases

Neurosurgical operations have traditionally been classified along the lines of general surgical procedures. A prospective study, during an 18-month period, was undertaken in 2249 patients undergoing neurosurgical procedures to establish and evaluate a method of classifying surgical cases by the use of specific neurosurgical criteria. Patients were placed in one of five categories according to the level and type of contamination at the time of surgery. Infection included all abnormal wounds and was documented as deep when infection occurred beneath the galea (subgaleal pus, osteitis, abscess/empyema, ventriculomeningitis) and as superficial if only the scalp (including wound erythema) was involved. A statistically significant difference in the sepsis rate was found in the different categories (P < 0.0001). Of the 342 "dirty cases," 9.1% of patients developed further wound sepsis. Concomitant cerebrospinal fluid fistulae (44%), second operations (11.8%), and patients with penetrating injuries (9.2%) were the major factors implicated in sepsis in the "contaminated" category (9.7%). In the "clean contaminated" category, a sepsis rate of 6.8% was found. Prolonged surgery (longer than 4 hours) was also implicated in higher infection rates (13.4%). This study strongly supports the separation of patients who have foreign materials implanted (sepsis rate = 6.0%) from "clean" patients, essentially cases categorized as having no known risk factors that may affect sepsis, in whom a sepsis rate of 0.8% was found (P < 0.001). Importantly, surgery for the repair of so-called "clean" neural tube defects in neonates requires separate consideration. An infection rate of 14.8% existed in this subgroup. A uniform system of reporting wound abnormalities is also proposed.

Ceftizoxime versus vancomycin and gentamicin in neurosurgical prophylaxis: a randomized, prospective, blinded clinical study

In a prospective, randomized, blinded study, 826 patients undergoing clean neurosurgical procedures received single intravenous doses of ceftizoxime (2 g) (n = 422) or a combination of vancomycin (1 g) and gentamicin (80 mg) (n = 404) 1 hour before an incision was made. Patients with infected or contaminated wounds and those receiving shunts or other implants were excluded. Primary wound infections occurred within 30 days in five patients in each group and were most common after spinal surgery and procedures through previous incisions. Secondary infections (pneumonias, urinary tract infections, and intravenous line-related bacteremia) occurred in 24 patients in the ceftizoxime group and 25 in the vancomycin/gentamicin group. The infection rates after transsphenoidal procedures (n = 129) were remarkably low in both groups. Ceftizoxime caused no adverse drug reactions, but six patients in the vancomycin/gentamicin group had clinically significant infusion-related hypotension or flushing. Placement of a temporary external drain, use of an operating microscope, preoperative steroids, and diabetes were not associated with increased infection rates. Analysis of routinely encountered ventricular cerebrospinal fluid and simultaneously obtained peripheral blood showed low but detectable levels of all three antibiotics within 2 hours; only ceftizoxime, however, achieved cerebrospinal fluid levels sufficient to inhibit the staphylococcus and Gram-negative bacilli most often associated with postneurosurgical infections. We conclude that ceftizoxime is as effective as vancomycin and gentamicin in neurosurgical prophylaxis but is less toxic and penetrates cerebrospinal fluid better.

Risk factors in postoperative neurosurgical infection. A prospective study

Four hundred and seventy patients who had undergone neurosurgical operations were studied prospectively. After defining post-operative infection so that is included all the infective complications irrespective of location occurring after surgery, the overall infection rate was 17%. The infection rate in 413 cases without pre-existing infection was 15%. Wound infection was recorded in 5% and meningitis in 6%. Risk factors which lead to a significant increase in the incidence of postoperative infection were found to be altered sensorium, multiple operations, pre-existing infection, emergency surgery, duration of surgery more than 4 hours, urinary catheterisation, cerebrospinal fluid leak, and ventilatory support.

Antibiotic prophylaxis during prolonged clean neurosurgery. Results of a randomized double-blind study using oxacillin

The efficacy of oxacillin as a prophylaxis for infection was analyzed in a 27-month randomized double-blind study of 400 patients who had undergone clean neurosurgical interventions lasting longer than 2 hours. Four neurosurgeons took part in the study and 356 patients were eligible for final analysis. Among the 171 patients treated with oxacillin, there was one case of infection (0.6%), compared to nine (4.9%) of the 185 patients given a placebo. The difference between the two groups was statistically significant (p = 0.0398). This study, together with others (randomized or not), clearly demonstrates the efficacy of antibiotic prophylaxis in prolonged clean neurosurgery.

Five days versus one day of penicillin as prophylaxis in elective neurosurgical operations

Of 423 patients undergoing elective cranial and spinal operations, infections due to Staphylococcus aureus occurred in 3 of 217 (1.4%) receiving penicillin for 1 day, in none of 206 receiving penicillin for 5 days. There was no significant difference in rates of infection between the two groups receiving penicillin. It is concluded that penicillin for 1 day is as effective as penicillin for 5 days, in the prevention of wound infections due to S. aureus.

A double-blind placebo-controlled trial of perioperative prophylactic antibiotics for elective neurosurgery

In this study, 417 patients undergoing "clean" elective neurosurgical operative procedures were randomized to receive a broad-spectrum antibiotic (piperacillin) or placebo given as three perioperative doses, each 6 hours apart. Randomization was carried out by hospital pharmacists, and the investigators remained blinded until the end of the study. Twenty cases were excluded from analysis because either an unforeseen second operation was performed or antibiotic therapy was initiated within 30 days after surgery to treat infection or the risk of infection. Twelve of the 205 patients treated with placebo developed postoperative wound sepsis, and four of the 192 piperacillin-treated patients developed wound sepsis--a statistically significant difference (p less than 0.05, Fisher's exact test). Piperacillin thus appeared to reduce the incidence of neurosurgical wound infection in this study.

Simple peroperative antimicrobial chemoprophylaxis in elective neurosurgical operations

From August 1981 to February 1982 postoperative infections due to different strains of penicillin-resistant Staphylococcus aureus occurred in 20 of 467 patients (4.3%) undergoing elective cranial and spinal operations. These infections were not attributable to defects in procedures or the theatre environment, therefore chemoprophylaxis was instituted. In the following 8 months, when patients were given penicillin G and sulphadiazine for 5 days commencing immediately postoperatively, S. aureus infections occurred in five of 579 patients (0.9%). In a subsequent randomized uncontrolled study, infections occurred in six of 265 patients receiving penicillin (2.3%), three of 270 receiving penicillin and sulphadiazine (1.1%) and one of 45 receiving erythromycin (2.2%) immediately postoperatively for 5 days. In a further study in which 587 patients received penicillin for 5 days commencing immediately preoperatively, infections due to S. aureus occurred in six (1.1%). Infections due to gram-negative organisms were seen in five (0.4%) of 1167 patients in the two uncontrolled studies.

Prophylactic parenteral antibiotics in clean neurosurgical procedures: a review

Clean surgical procedures carry a risk of postoperative wound infection that is less than 5% in most hospitals. The use of prophylactic antibiotic agents in clean neurosurgical cases is controversial, and the neurosurgical literature through 1980 contains no controlled clinical trials to study its effectiveness in such cases. A report of 1732 consecutive procedures without a single postoperative wound infection in patients receiving systemic gentamicin, vancomycin, and streptomycin irrigation fluids is often quoted by neurosurgeons; however, these results have not yet been duplicated by others. Since 1980, there have been several controlled trials that support the use in clean neurosurgical cases of prophylactic antibiotics, including the vancomycin/gentamicin/streptomycin regimen and the first-generation cephalosporins. A report in 1986 of 1602 cases without a primary wound infection supports the use of a single perioperative dose of cefazolin. A review of causative organisms in postoperative wound infections demonstrates the preponderance of Gram-positive pathogens. Therefore, when antibiotic prophylaxis is indicated, adequate Gram-positive bacterial coverage, including protection against Staphylococcus infection, is required. With consideration of the present data, the cost of antibiotic therapy, and the danger of drug toxicity, a short perioperative regimen of cefazolin as prophylaxis is preferred in clean neurosurgical cases.

Antibiotic prophylaxis in neurosurgery. Study comparing two groups of patients with and without treatment

We present the results of a study comparing two groups of patients who underwent neurosurgical operations, one pretreated with Ampicillin (184) and the other not (193), in comparable time-spans. The results of this study argue for a beneficial action of Ampicillin prophylaxis on neurosurgical infections. A brief discussion of the appropriate literature is given.

Craniotomy flap osteomyelitis: a diagnostic approach

Nine cases of suspected craniotomy flap osteomyelitis evaluated by combined bone and gallium scanning are presented. In six cases, the clinical data were inconclusive and evaluation by radionuclide imaging provided an accurate negative diagnosis. The other three cases considered positive by this technique were proven infected at subsequent exploration and flap removal. The use of radionuclide bone and gallium imaging should be considered in cases of possible craniotomy flap osteomyelitis.

Randomized clinical trial of intra-operative antimicrobial prophylaxis of infection after neurosurgical procedures

A randomized, placebo-controlled, double-blind and sequentially analysed clinical trial to determine the efficacy of intra-operative parenteral gentamicin and vancomycin (with streptomycin in the irrigating solution) in preventing infection at the operative site following neurosurgical procedures is described. Patients receiving prophylaxis had a significantly (P = 0.046) lower operative site infection rate (2/71 = 2.8%) than those receiving placebo (9/77 = 11.7%). This difference was most apparent during an epidemic, the source of which was not evident. Moreover, a total of 13 infections (two operative site, five pneumonia and six urinary tract) occurred among 12 patients receiving prophylaxis, whereas there was a total of 31 infections (nine operative site, nine pneumonia, 10 urinary tract and three septicaemia) among 24 patients receiving placebo. A smaller quantity of antimicrobial drugs was administered postoperatively to patients receiving prophylaxis (3.96 'antibiotic-days' per patient) than to those receiving placebo (6.87 'antibiotic-days' per patient).