Coagulopathy in Penetrating Ballistic Cranial Trauma: A 7-Year Experience.

BACKGROUND AND OBJECTIVES: Penetrating ballistic cranial trauma (PBCT) carries significant mortality when compared with blunt trauma. The development of coagulopathy in PBCT is a strong predictor of mortality. The goal of the study was to describe the incidence and risk factors of coagulopathy in PBCT and to report the value of tranexamic acid administration in PBCT. METHODS: We retrospectively analyzed 270 patients who presented with PBCT to a single, Level 1 trauma center between 2016 and 2023. RESULTS: A total of 47% (127/270) of patients with PBCT developed coagulopathy at presentation. Fifty-seven patients received tranexamic acid at presentation, which did not affect the development of coagulopathy. Coagulopathic patients were more likely to have more serious injury patterns (bihemispheric [adjusted odds ratio, aOR: 2.6 CI: 1.4-4.9, P = .004] or transventricular trajectories [aOR: 4.9 CI: 1.9-19.6, P = .03]). In addition, they presented with a larger base deficit (aOR: 0.9 CI: 1.002-1.2 per mEq/L, P = .006) which negatively correlated with the international normalized ratio (ρ: -0.46, P < .0001, Spearman correlation). Using thromboelastography helped to identify an additional 20% of patients who presented with normal coagulation on conventional testing. CONCLUSION: Coagulopathy is prevalent in approximately 50% of patients with PBCT and is persistent despite treatment in a substantial subset of patients. The addition of thromboelastography with its increased coagulopathy sensitivity can potentially guide treatment more efficiently than traditional coagulopathy laboratory tests and fibrinogen alone. Patients with a significant base deficit on arterial blood gas are at higher risk for coagulopathy.

The Neurosurgeon's Dilemma-Do Antiplatelet/Anticoagulant Medications Increase the Risk of Catheter-Associated Hemorrhage in External Ventricular Drain Placement?

OBJECTIVE: External ventricular drain (EVD) placement is a common neurosurgical procedure that can be performed at bedside. A frequent complication following EVD placement is catheter-associated hemorrhage (CAH). The hemorrhage itself is rarely clinically significant but may be complicated in patients taking anticoagulant or antiplatelet (AC/AP) medications. METHODS: A total of 757 patients were who underwent EVD placement at bedside were included as part of a retrospective study at a large academic medical center. Demographic factors, use of AC/AP therapies, and several other clinical variables were recorded and assessed in univariate and multivariate regression analysis for association with CAH and mortality. RESULTS: One hundred (13.2%) patients experienced CAH within 24 hours of the procedure. After univariate analysis, in 2 tandem-run multivariate regression analyses after stepwise variable selection, use of 2 or more AC/AP agents (odds ratio [OR] = 2.362, P = 0.020) and dual antiplatelet therapy with aspirin and clopidogrel (OR = 3.72, P = 0.009) were significantly associated with CAH. Use of noncoated catheters was a protective factor against CAH compared to use of antibiotic-coated catheters (OR = 0.55, P = 0.019). Multivariate analysis showed age, multiagent therapy, and thrombocytopenia were significantly associated with increased mortality. CONCLUSIONS: There was increased risk of CAH after EVD placement in patients taking more than one AC/AP agent regardless of presenting pathology. In particular, use of aspirin and clopidogrel combined was associated with significantly higher odds of CAH, although it was not associated with higher mortality. In addition, there appears to be an association between use of antibiotic-coated catheters and CAH across univariate and multivariate analysis.

Differences in microorganisms causing infection after cranial and spinal surgeries.

OBJECTIVE: The primary aim of this retrospective study was to assess differences in the pathogens causing surgical site infections (SSIs) following craniectomies/craniotomies and open spinal surgery. The secondary aim was to assess differences in rates of SSI among these operative procedures. METHODS: ANOVA tests with Bonferroni correction and incidence risk ratios (RRs) were used to identify differences in pathogens by surgical site and procedure using retrospective, de-identified records of 19,993 postneurosurgical patients treated between 2007 and 2020. RESULTS: The overall infection rates for craniotomy/craniectomy, laminectomy, and fusion were 2.1%, 1.1%, and 1.5%, respectively, and overall infection rates for cervical, thoracic, and lumbar spine surgery were 0.3%, 1.6%, and 1.9%, respectively. Craniotomy/craniectomy was more likely to result in an SSI than spine surgery (RR 1.8, 95% CI 1.4-2.2, p < 0.0001). Cutibacterium acnes (RR 24.2, 95% CI 7.3-80.0, p < 0.0001); coagulase-negative staphylococci (CoNS) (methicillin-susceptible CoNS: RR 2.9, 95% CI 1.6-5.4, p = 0.0006; methicillin-resistant CoNS: RR 5.6, 95% CI 1.4-22.3, p = 0.02); Klebsiella aerogenes (RR 6.5, 95% CI 1.7-25.1, p = 0.0003); Serratia marcescens (RR 2.4, 95% CI 1.1-7.1, p = 0.01); Enterobacter cloacae (RR 3.1, 95% CI 1.2-8.1, p = 0.02); and Candida albicans (RR 3.9, 95% CI 1.2-12.3, p = 0.02) were more commonly associated with craniotomy/craniectomy cases than fusion or laminectomy SSIs. Pseudomonas aeruginosa was more commonly associated with fusion SSIs than craniotomy SSIs (RR 4.4, 95% CI 1.3-14.8, p = 0.02), whereas Escherichia coli was nonsignificantly associated with fusion SSIs compared to craniotomy SSIs (RR 4.1, 95% CI 0.9-18.1, p = 0.06). Infections with E. coli and P. aeruginosa occurred primarily in the lumbar spine (p = 0.0003 and p = 0.0001, respectively). CONCLUSIONS: SSIs due to typical gastrointestinal or genitourinary gram-negative bacteria occur most commonly following lumbar surgery, particularly fusion, and are likely to be due to contamination of the surgical bed with microbial flora in the perianal area and genitourinary tract. Cutibacterium acnes in the skin flora of the head and neck increases risk of infection due to this microbe following surgical interventions in these body sites. The types of gram-negative bacteria associated with craniotomy/craniectomy SSIs suggest potential environmental sources of these pathogens. Based on the authors' findings, neurosurgeons should consider using a two-step skin preparation with benzoyl peroxide, in addition to a standard antiseptic such as alcoholic chlorhexidine for cranial, cervical, and upper thoracic surgeries. Additionally, broader gram-negative bacterial coverage, such as use of a third-generation cephalosporin, should be considered for lumbar/lumbosacral fusion surgical antibiotic prophylaxis.

Near-lifespan longitudinal tracking of brain microvascular morphology, topology, and flow in male mice.

In age-related neurodegenerative diseases, pathology often develops slowly across the lifespan. As one example, in diseases such as Alzheimer's, vascular decline is believed to onset decades ahead of symptomology. However, challenges inherent in current microscopic methods make longitudinal tracking of such vascular decline difficult. Here, we describe a suite of methods for measuring brain vascular dynamics and anatomy in mice for over seven months in the same field of view. This approach is enabled by advances in optical coherence tomography (OCT) and image processing algorithms including deep learning. These integrated methods enabled us to simultaneously monitor distinct vascular properties spanning morphology, topology, and function of the microvasculature across all scales: large pial vessels, penetrating cortical vessels, and capillaries. We have demonstrated this technical capability in wild-type and 3xTg male mice. The capability will allow comprehensive and longitudinal study of a broad range of progressive vascular diseases, and normal aging, in key model systems.

Investigating the correlation between early vascular alterations and cognitive impairment in Alzheimer's disease in mice with SD-OCT.

Vascular alterations have recently gained some attention with their strong association with Alzheimer's disease (AD). We conducted a label-free in vivo optical coherence tomography (OCT) longitudinal imaging using an AD mouse model. We achieved the tracking of the same individual vessels over time and conducted an in-depth analysis of temporal dynamics in vasculature and vasodynamics using OCT angiography and Doppler-OCT. The AD group showed an exponential decay in both vessel diameter and blood flow change with the critical timepoint before 20 weeks of age, which precedes cognitive decline observed at 40 weeks of age. Interestingly, for the AD group, the diameter change showed the dominance in arterioles over venules, but no such influence was found in blood flow change. Conversely, three mice groups with early vasodilatory intervention did not show any significant change in both vascular integrity and cognitive function compared to the wild-type group. We found early vascular alterations and confirmed their correlation with cognitive impairment in AD.

Time of Discharge and 30-Day Re-Presentation to an Acute Care Setting After Elective Lumbar Decompression Surgery.

BACKGROUND: Evidence regarding the consequence of efforts to increase patient throughput and decrease length of stay in the context of elective spine surgery is limited. OBJECTIVE: To evaluate whether early time of discharge results in increased rates of hospital readmission or return to emergency department for patients admitted after elective, posterior, lumbar decompression surgery. METHODS: We conducted a retrospective cohort study of 779 patients admitted to hospital after undergoing elective, posterior, lumbar decompression surgery. Multiple logistic regression evaluated the relationship between time of discharge and the primary outcome of return to acute care within 30 days, while controlling for sociodemographic, procedural, and discharge characteristics. RESULTS: In multiple logistic regression, time of discharge earlier in the day was not associated with increased odds of return to acute care within 30 days (odds ratio [OR] 1.18, 95% CI 0.92-1.52, P = .19). Weekend discharge (OR 1.99, 95% CI 1.04-3.79, P = .04) increased the likelihood of return to acute care. Surgeon experience (<1 year of attending practice, OR 0.43, 95% CI 0.19-1.00, P = .05 and 2-5 years of attending practice, OR 0.50, 95% CI 0.25-1.01, P = .054), weekend discharge (OR 0.49, 95% CI 0.27-0.89, P = .02), and physical therapy evaluation (OR 0.20, 95% CI 0.12-0.33, P < .001) decreased the likelihood of discharge before noon. CONCLUSION: Time of discharge is not associated with risk of readmission or presentation to the emergency department after elective lumbar decompression. Weekend discharge is independently associated with increased risk of readmission and decreased likelihood of prenoon discharge.

Reducing ventriculoperitoneal shunt infection with intraoperative glove removal.

BACKGROUND: Contamination of ventriculoperitoneal shunts (VPS) by cutaneous flora, particularly coagulase-negative staphylococci, is a common cause of shunt infection and failure, leading to prolonged hospital stay, higher costs of care, and poor outcomes. Glove contamination may occur during VPS insertion, increasing risk of such infections. METHODS: We performed a systematic search of the PubMed database for studies published January 1, 1970, through August 31, 2021 that documented VPS infection rates before and after implementing a practice of double gloving with change or removal of the outer glove immediately prior to shunt insertion. RESULTS: Among 272 reports screened, 4 were eligible for review based on our inclusion criteria. The incidence of VPS infection was reduced in all 4 quasi-experimental studies with an aggregate incidence of VPS infection of 11.8% before the change in intraoperative protocol and 4.9% after protocol change. One study documented reduced hospital stay with this change in protocol. CONCLUSION: The risk of VPS infection is reduced by removal or replacement of the outer surgical gloves immediately prior to intraoperative insertion of a VPS as part of an infection control bundle.

Development of posttraumatic frontal brain abscess in association with an orbital roof fracture and odontogenic abscess: A case report.

Background: Brain abscess is a potentially fatal condition. Orbital fractures caused by penetrating injury may be associated with intracranial infection. Such complication associated with blunt trauma, orbital roof fractures, and odontogenic abscesses is exceedingly rare. Case Description: We report the case of a 40-year-old transgender female with a frontal abscess presenting several weeks following a motor vehicle crash from which she suffered multiple facial fractures and an odontogenic abscess. On computed tomography scan, the patient had multiple right-sided facial fractures, including a medial orbital wall fracture and a right sphenoid fracture extending into the superior orbital roof. There was hemorrhage notable in the right frontal lobe. Communication with the ethmoid sinuses likely provided a conduit for bacterial spread through the orbit and into the intracranial and subdural spaces. Conclusion: Skull base fractures that communicate with a sinus, whether it be frontal, ethmoid, or sphenoid may increase the risk of brain abscess, especially in patients who develop an odontogenic abscess. Surgical repair of the defect is essential, and treating patients prophylactically with antibiotics may be beneficial.

Incidence, Characteristics, and Outcomes of Pseudomeningocele and Cerebrospinal Fluid Fistula after Posterior Fossa Surgery.

OBJECTIVE: Posterior fossa approaches are common neurosurgical procedures. Rates of postoperative infection, pseudomeningocele, and cerebrospinal fluid (CSF) fistula are high; however, evidence regarding predisposing risk factors and treatment outcomes remain sparse. METHODS: A retrospective cohort study was carried out of all posterior fossa surgeries conducted at a single institution between January 2015 and October 2019. Univariate statistical methods and stepwise logistic regression were used to assess which factors contributed most to risk of development of postoperative complications. RESULTS: A total of 269 patients were included; 18.6% experienced any postoperative complication, 13% developed either pseudomeningocele or CSF fistula, and 9.7% developed an infection. In multivariate analysis, development of a pseudomeningocele was significantly associated with previous cranial surgery (hazard ratio [HR], 3.15; 95% confidence interval [CI], 1.12-9.28; P = 0.0391). Development of a CSF fistula was significantly associated with index surgery for resection of neoplasm (HR, 7.65; 95% CI, 1.86-22.31; P = 0.0174). Development of an infection was significantly associated with concurrent CSF fistula (HR, 7.16; 95% CI, 1.91-23.19; P = 0.0041) and concurrent pseudomeningocele (HR, 3.41; 95% CI, 1.37-5.95; P = 0.0082) and nonsignificantly associated with diabetes requiring treatment (HR, 2.42; 95% CI, 0.69-8.50; P = 0.168). Other hypothesized risk factors for these complications, such as nonmidline approaches to the posterior fossa, watertight duraplasty, use of dural fibrin sealant, and cranioplasty were not associated with these complications on multivariate analysis. Although many patients with pseudomeningocele were successfully managed with observation, only 38% of patients in whom CSF diversion was attempted avoided surgery. CONCLUSIONS: History of diabetes, cranioplasty, revision surgery, and surgery for tumor resection are identified as risk factors for the development of infection, pseudomeningocele, and CSF fistula, respectively.

Risk factors and outcomes associated with external ventricular drain infections.

BACKGROUND: Insertion of an external ventricular drain (EVD) is a common neurosurgical procedure which may lead to serious complications including infection. Some risk factors associated with EVD infection are well established. Others remain less certain, including specific indications for placement, prior neurosurgery, and prior EVD placement. OBJECTIVE: To identify risk factors for EVD infections. METHODS: We reviewed all EVD insertions at our institution from March 2015 through May 2019 following implementation of a standardized infection control protocol for EVD insertion and maintenance. Cox regression was used to identify risk factors for EVD infections. RESULTS: 479 EVDs placed in 409 patients met inclusion criteria, and 9 culture-positive infections were observed during the study period. The risk of infection within 30 days of EVD placement was 2.2% (2.3 infections/1,000 EVD days). Coagulase-negative staphylococci were identified in 6 of the 9 EVD infections). EVD infection led to prolonged length of stay post-EVD-placement (23 days vs 16 days; P = .045). Cox regression demonstrated increased infection risk in patients with prior brain surgery associated with cerebrospinal fluid (CSF) diversion (HR, 8.08; 95% CI, 1.7-39.4; P = .010), CSF leak around the catheter (HR, 21.0; 95% CI, 7.0-145.1; P = .0007), and insertion site dehiscence (HR, 7.53; 95% CI, 1.04-37.1; P = .0407). Duration of EVD use >7 days was not associated with infection risk (HR, 0.62; 95% CI, 0.07-5.45; P = .669). CONCLUSION: Risk factors associated with EVD infection include prior brain surgery, CSF leak, and insertion site dehiscence. We found no significant association between infection risk and duration of EVD placement.

Decreasing External Ventricular Drain Infection Rates in the Neurocritical Care Unit: 12-Year Longitudinal Experience at a Single Institution.

OBJECTIVE: External ventricular drain (EVD) placement is a common neurosurgical procedure, and EVD-related infection is a significant complication. We examined the effect of infection control protocol changes on EVD-related infection incidence. METHODS: Changes in EVD placement protocol and incidence density of infections after implementation of protocol changes in the neurocritical care unit were tracked from 2007 to 2019. EVD infections were defined using a modified U.S. Centers for Disease Control and Prevention National Healthcare Safety Network surveillance definition of meningitis/ventriculitis for patients with EVDs in situ for at least 2 days confirmed by positive culture. Contribution of protocol changes to EVD infection risk was assessed via multivariate regression. RESULTS: Fifteen major changes in EVD protocol were associated with a reduction in infections from 6.7 to 2.0 per 1000 EVD days (95% confidence interval [CI], 4.1-5.3; P < 0.001). Gram-positive bacterial infection incidence decreased from 4.8 to 1.7 per 1000 EVD days (95% CI, 2.3-3.9; P = 0.00882) and gram-negative infection incidence decreased from 1.9 to 0.5 per 1000 EVD days (95% CI, 0.6-2.3; P = 0.0303). Of all protocol changes since 2007, the largest reduction in incidence was 3.9 infections per 1000 days (95% CI, 0.50-7.30; P = 0.011), associated with combined standardization of reduced EVD sampling frequency, cutaneous antisepsis with alcoholic chlorhexidine before EVD placement, and use of a subcutaneous tunneling technique during EVD insertion. CONCLUSIONS: The most significant reduction in EVD infections may be achieved through the combination of reducing EVD sampling frequency and standardizing alcoholic chlorhexidine cutaneous antisepsis and subcutaneous tunneling of the EVD catheter.

Spinal Epidural Hematoma After Attempted Catheter Thrombectomy of a Large Iliofemoral Deep Venous Thrombosis: A Case Report.

The authors report the case of an 82-year-old woman with a spinal epidural hematoma following attempted catheter-directed thrombolysis of a large femoral- popliteal deep venous thrombosis. The patient rapidly developed acute motor and sensory paralysis below the level of T7 within hours of the thrombectomy procedure. Computed tomography imaging revealed that the catheter had perforated the wall of the right inferior vena cava and magnetic resonance imaging subsequently demonstrated an extensive T1-S1 dorsal epidural hematoma with compression of the thoracic spinal cord, conus medullaris, and cauda equina. Given the extent of cord infarction and the risks of extensive thoracolumbar laminectomy, decompression was not performed. The incidence, diagnosis, and management of anticoagulation- associated spinal epidural hematoma as well as the indications for catheter-directed thrombolysis of acute deep venous thrombosis are reviewed.

Doppler OCT clutter rejection using variance minimization and offset extrapolation.

Doppler optical coherence tomography (OCT) is widely used for high-resolution mapping of flow velocities and is based on analysis of temporal changes in the phase of an OCT signal (i.e., how fast the OCT signal rotates in the complex plane). Determination of the rate of phase change or rotation speed critically depends on the center of rotation. Here, we demonstrate the bias in high-pass filtering, the current widely used method to determine the center of rotation, and propose two advanced methods for Doppler OCT clutter rejection. The bias in the high-pass filtering method becomes increasingly significant with lower velocities or larger signal noise. Two novel methods based on variance minimization and offset extrapolation can potentially reduce this bias and thereby improve the accuracy of Doppler OCT measurements of flow velocities, even for low-velocity and/or high-noise signals. The two novel methods and the current standard method (high-pass filtering) have been tested in combination with several currently used velocity measurement algorithms: Kasai, autocorrelation function fitting, and maximum likelihood estimation. The newly proposed methods are shown to improve the accuracy in both the center of rotation and resultant velocity by up to 60 percentage points and reduce the flow conservation error by 30% when applied to in vivo cerebral blood flow imaging of the rodent brain cortex.