Effect of intermittent high-frequency stimulation on muscle velocity recovery cycle recordings.

The technique of multifiber muscle velocity recovery cycle recordings was developed as a diagnostic tool to assess muscle membrane potential changes and ion channel function in vivo. This study was undertaken to assess the impact of intermittent high-frequency stimulation on muscle velocity recovery cycle components and to study whether the changes can be modified by endurance training. We recorded muscle velocity recovery cycles with 1 and 2 conditioning stimuli in the left tibialis anterior muscle in 15 healthy subjects during intermittent 37-Hz stimulation and analyzed its effects on the different phases of supernormality. Recordings were conducted before and after 2-wk endurance training. Training effect was assessed by measuring the difference in endurance time, peak force, and limb circumference. Muscle velocity recovery cycle recordings during intermittent high-frequency stimulation were successfully recorded in 12 subjects. Supernormality for interstimulus intervals shorter than 15 ms (early supernormality) was maximally reduced at the beginning of repetitive stimulation and recovered during stimulation. Supernormality for interstimulus intervals between 50 and 150 ms (late supernormality) showed a delayed decrease and stayed significantly reduced after high-frequency stimulation. Training had no significant effect on any of the measured parameters, but we found that training induced changes in peak force correlated positively with baseline changes of early supernormality. Our results support the hypothesis that early supernormality represents membrane potential, which depolarizes in the beginning of high-frequency stimulation. Late supernormality probably reflects transverse tubular function and shows progressive changes during high-frequency stimulation with delayed normalization.NEW & NOTEWORTHY A conditioning impulse in human muscle fibers induces a prolonged phase of increased velocity (also called supernormality) with two phases related to an early and late afterpotential. We investigated the effects of intermittent 37-Hz stimulation on muscle fiber supernormality and found that the early and late phases of supernormality changed differently, and that the late phase may reflect the ionic interactions responsible for the counter-regulation of muscle fatigue.

Individualized Brain Tissue Oxygen-Monitoring Probe Placement Helps to Guide Therapy and Optimizes Outcome in Neurocritical Care.

BACKGROUND/OBJECTIVE: In order to monitor tissue oxygenation in patients with acute neurological disorders, probes for measurement of brain tissue oxygen tension (ptO2) are often placed non-specifically in a right frontal lobe location. To improve the value of ptO2 monitoring, placement of the probe into a specific area of interest is desirable. We present a technique using CT-guidance to place the ptO2 probe in a particular area of interest based on the individual patient's pathology. METHODS: In this retrospective cohort study, we analyzed imaging and clinical data from all patients who underwent CT-guided ptO2 probe placement at our institution between October 2017 and April 2019. Primary endpoint was successful placement of the probe in a particular area of interest rated by two independent reviewers. Secondary outcomes were complications from probe insertion, clinical consequences from ptO2 measurements, clinical outcome according to the modified Rankin Scale (mRS) as well as development of ischemia on follow-up imaging. A historical control group was selected from patients who underwent conventional ptO2 probe placement between January 2010 and October 2017. RESULTS: Eleven patients had 16 CT-guided probes inserted. In 15 (93.75%) probes, both raters agreed on the correct placement in the area of interest. Each probe triggered on average 0.48 diagnostic or therapeutic adjustments per day. Only one infarction within the vascular territory of a probe was found on follow-up imaging. Eight out of eleven patients (72.73%) reached a good outcome (mRS ≤ 3). In comparison, conventionally placed probes triggered less diagnostic and therapeutic adjustment per day (p = 0.007). Outcome was worse in the control group (p = 0.024). CONCLUSION: CT-guided probe insertion is a reliable and easy technique to place a ptO2 probe in a particular area of interest in patients with potentially reduced cerebral oxygen supply. By adjusting treatment aggressively according to this individualized monitoring data, clinical outcome may improve.

Velocity and pattern of growth of intracranial meningiomas.

OBJECTIVE: The authors' aim was to assess the velocity and pattern of growth of meningiomas and to correlate the kinetics of tumor growth with their previously reported two-item radiological risk stratification and CNS WHO grade (5th edition, 2021). METHODS: The authors performed a serial volumetric analysis of meningiomas diagnosed radiologically at their institution between 2003 and 2015. The primary endpoint was velocity of diametric expansion (VDE), which represents the slope of the linear regression of the mean tumor diameter against time. For the secondary analysis, they categorized the growth patterns as linear or exponential by fitting time-volume curves to a linear and exponential function. Three radiological risk categories based on T2-weighted iso/hyperintensity and absence of calcifications were compared: low risk (T2-weighted hypointense), intermediate-risk (T2-weighted iso/hyperintense with calcifications), and high-risk (T2-weighted iso/hyperintense without calcifications) tumors. RESULTS: For the entire cohort of 240 meningiomas, the median (IQR) VDE was 0.33 (0.00-0.71) mm/year. Distribution of VDE differed significantly among radiological risk categories (0.49 vs 0.35 vs 0.05 mm/year, p < 0.001). High-risk and intermediate-risk tumors more frequently tended to grow exponentially compared to low-risk tumors (43.8% vs 37.0% vs 8.3%, p = 0.067). The authors found no correlation of growth velocity with CNS WHO grade in their cohort (1.30 mm/year for CNS WHO grade 1 vs 4.01 mm/year for CNS WHO grade 2, p = 0.185). CONCLUSIONS: A radiological risk assessment using two parameters-T2-weighted signal iso/hyperintensity and absence of calcifications-allows estimation of growth velocity and characteristics of untreated intracranial meningiomas. Only high-risk tumors exhibit the potential for rapid growth. However, rapid tumor growth does not indicate a higher CNS WHO grade per se.

Tolerability of COVID-19 mRNA vaccines in patients with postural tachycardia syndrome: a cross-sectional study.

Background: Postural tachycardia syndrome (POTS) is a form of autonomic dysregulation. There is increasing evidence that the etiology may be immune-mediated in a subgroup of patients. Patients with POTS often experience an exacerbation of their symptoms associated with (viral) infections and often fear the same symptom aggravation after vaccination. In this report we describe the tolerability of messenger ribonucleic acid (mRNA) vaccines against coronavirus disease 19 (COVID-19) and the consequences of a COVID-19 infection on POTS symptoms in our cohort of patients with neuropathic POTS. Methods: We conducted a standardized, checklist-based interview with 23 patients and recorded the acute side effects of mRNA vaccination, acute symptoms of COVID-19 infection as well as the effects of vaccination and COVID-19 infection on POTS symptoms. Results: Of all included patients, 20 patients received two mRNA vaccines without having had a previous COVID-19 infection, and five patients in total had suffered a COVID-19 infection. Of these, three had COVID-19 without and two after being vaccinated. No increased frequency of side effects after both doses of mRNA vaccines was observed. Six patients reported a mild and short-term aggravation of their POTS symptoms beyond the duration of acute vaccine side effects. All five patients who suffered a COVID-19 infection subsequently reported a pronounced and persistent exacerbation of POTS symptoms. Conclusions: Our observations suggest that mRNA vaccines are not associated with a higher frequency of acute side effects in patients with POTS. Symptom exacerbation as a consequence of mRNA vaccination seems to be less frequent and of shorter duration compared to patients who suffered a COVID-19 infection.

Quantitative Analysis of the MGMT Methylation Status of Glioblastomas in Light of the 2021 WHO Classification.

Background: Glioblastomas with methylation of the promoter region of the O(6)-methylguanine-DNA methyltransferase (MGMT) gene exhibit increased sensitivity to alkylating chemotherapy. Quantitative assessment of the MGMT promoter methylation status might provide additional prognostic information. The aim of our study was to determine a quantitative methylation threshold for better survival among patients with glioblastomas. Methods: We included consecutive patients ≥18 years treated at our department between 11/2010 and 08/2018 for a glioblastoma, IDH wildtype, undergoing quantitative MGMT promoter methylation analysis. The primary endpoint was overall survival. Results: A total of 321 patients were included. Median overall survival was 12.6 months. Kaplan−Meier and adjusted Cox regression analysis showed better survival for the groups with 16−30%, 31−60%, and 61−100% methylation. In contrast, survival in the group with 1−15% methylation was similar to those with unmethylated promoter regions. A secondary analysis confirmed this threshold. Conclusions: Better survival is observed in patients with glioblastomas with ≥16% methylation of the MGMT promoter region than with <16% methylation. Survival with tumors with 1−15% methylation is similar to with unmethylated tumors. Above 16% methylation, we found no additional benefit with increasing methylation.

Development and early diagnosis of critical illness myopathy in COVID-19 associated acute respiratory distress syndrome.

BACKGROUND: The COVID-19 pandemic has greatly increased the incidence and clinical importance of critical illness myopathy (CIM), because it is one of the most common complications of modern intensive care medicine. Current diagnostic criteria only allow diagnosis of CIM at an advanced stage, so that patients are at risk of being overlooked, especially in early stages. To determine the frequency of CIM and to assess a recently proposed tool for early diagnosis, we have followed a cohort of COVID-19 patients with acute respiratory distress syndrome and compared the time course of muscle excitability measurements with the definite diagnosis of CIM. METHODS: Adult COVID-19 patients admitted to the Intensive Care Unit of the University Hospital Bern, Switzerland requiring mechanical ventilation were recruited and examined on Days 1, 2, 5, and 10 post-intubation. Clinical examination, muscle excitability measurements, medication record, and laboratory analyses were performed on all study visits, and additionally nerve conduction studies, electromyography and muscle biopsy on Day 10. Muscle excitability data were compared with a cohort of 31 age-matched healthy subjects. Diagnosis of definite CIM was made according to the current guidelines and was based on patient history, results of clinical and electrophysiological examinations as well as muscle biopsy. RESULTS: Complete data were available in 31 out of 44 recruited patients (mean [SD] age, 62.4 [9.8] years). Of these, 17 (55%) developed CIM. Muscle excitability measurements on Day 10 discriminated between patients who developed CIM and those who did not, with a diagnostic precision of 90% (AUC 0.908; 95% CI 0.799-1.000; sensitivity 1.000; specificity 0.714). On Days 1 and 2, muscle excitability parameters also discriminated between the two groups with 73% (AUC 0.734; 95% CI 0.550-0.919; sensitivity 0.562; specificity 0.857) and 82% (AUC 0.820; CI 0.652-0.903; sensitivity 0.750; specificity 0.923) diagnostic precision, respectively. All critically ill COVID-19 patients showed signs of muscle membrane depolarization compared with healthy subjects, but in patients who developed CIM muscle membrane depolarization on Days 1, 2 and 10 was more pronounced than in patients who did not develop CIM. CONCLUSIONS: This study reports a 55% prevalence of definite CIM in critically ill COVID-19 patients. Furthermore, the results confirm that muscle excitability measurements may serve as an alternative method for CIM diagnosis and support its use as a tool for early diagnosis and monitoring the development of CIM.

Natural history of meningiomas: a serial volumetric analysis of 240 tumors.

OBJECTIVE: The management of asymptomatic intracranial meningiomas is controversial. Through the assessment of growth predictors, the authors aimed to create the basis for practicable clinical pathways for the management of these tumors. METHODS: The authors volumetrically analyzed meningiomas radiologically diagnosed at their institution between 2003 and 2015. The primary endpoint was growth of tumor volume. The authors used significant variables from the multivariable regression model to construct a decision tree based on the exhaustive Chi-Square Automatic Interaction Detection (CHAID) algorithm. RESULTS: Of 240 meningiomas, 159 (66.3%) demonstrated growth during a mean observation period of 46.9 months. On multivariable logistic regression analysis, older age (OR 0.979 [95% CI 0.958-1.000], p = 0.048) and presence of calcification (OR 0.442 [95% CI 0.224-0.872], p = 0.019) had a negative predictive value for tumor growth, while T2-signal iso-/hyperintensity (OR 4.415 [95% CI 2.056-9.479], p < 0.001) had a positive predictive value. A decision tree model yielded three growth risk groups based on T2 signal intensity and presence of calcifications. The median tumor volume doubling time (Td) was 185.7 months in the low-risk, 100.1 months in the intermediate-risk, and 51.7 months in the high-risk group (p < 0.001). Whereas 0% of meningiomas in the low- and intermediate-risk groups had a Td of ≤ 12 months, the percentage was 8.9% in the high-risk group (p = 0.021). CONCLUSIONS: Most meningiomas demonstrated growth during follow-up. The absence of calcifications and iso-/hyperintensity on T2-weighted imaging offer a practical way of stratifying meningiomas as low, intermediate, or high risk. Small tumors in the low- or intermediate-risk categories can be monitored with longer follow-up intervals.

Inhaled Nitric Oxide Treatment for Aneurysmal SAH Patients With Delayed Cerebral Ischemia.

BACKGROUND: We demonstrated experimentally that inhaled nitric oxide (iNO) dilates hypoperfused arterioles, increases tissue perfusion, and improves neurological outcome following subarachnoid hemorrhage (SAH) in mice. We performed a prospective pilot study to evaluate iNO in patients with delayed cerebral ischemia after SAH. METHODS: SAH patients with delayed cerebral ischemia and hypoperfusion despite conservative treatment were included. iNO was administered at a maximum dose of 40 ppm. The response to iNO was considered positive if: cerebral artery diameter increased by 10% in digital subtraction angiography (DSA), or tissue oxygen partial pressure (PtiO2) increased by > 5 mmHg, or transcranial doppler (TCD) values decreased more than 30 cm/sec, or mean transit time (MTT) decreased below 6.5 secs in CT perfusion (CTP). Patient outcome was assessed at 6 months with the modified Rankin Scale (mRS). RESULTS: Seven patients were enrolled between February 2013 and September 2016. Median duration of iNO administration was 23 h. The primary endpoint was reached in all patients (five out of 17 DSA examinations, 19 out of 29 PtiO2 time points, nine out of 26 TCD examinations, three out of five CTP examinations). No adverse events necessitating the cessation of iNO were observed. At 6 months, three patients presented with a mRS score of 0, one patient each with an mRS score of 2 and 3, and two patients had died. CONCLUSION: Administration of iNO in SAH patients is safe. These results call for a larger prospective evaluation.

Negligible Systemic Uptake of Suprafascial Vancomycin Powder Following Instrumented Posterior Spinal Fusion-Preliminary Results From A Randomized Clinical Trial (VANCO Trial).

BACKGROUND: Intrawound vancomycin powder is an emerging strategy to reduce surgical site infections (SSIs) in spine surgery. However, there are concerns relating to its safety profile and toxicity. Data on systemic uptake of suprafascially administered vancomycin powder following instrumented spinal fusion is lacking. OBJECTIVE: To study the systemic uptake and safety of suprafascially administered vancomycin powder in the early postoperative phase following open instrumented posterior spinal fusion. METHODS: This was a substudy of an ongoing randomized clinical trial. Eligible adult patients were randomized 1:1 to either receive suprafascial vancomycin powder before wound closure or not to receive vancomycin powder. Serum vancomycin levels were assessed on postoperative days 1 and 2, serum creatinine levels were measured pre- and post-operatively. Adverse events up to 6 wk following surgery were recorded. RESULTS: Among 34 randomized patients (mean age 62 yr, range 31-84 yr; 18 [53%] women), 17 received vancomycin powder. No detectable serum vancomycin levels (>4.0 mg/L) were found. Proportion of adverse events per patient in the vancomycin and control group, respectively, were 29.4% (5/17) vs 11.8% (2/17) (OR 3.12; 95% CI, 0.52; 19.38; P = .398). No patient had nephrotoxicity or ototoxicity in either group. CONCLUSION: Suprafascial vancomycin powder in open instrumented spinal fusion surgery is safe and results in negligible systemic uptake. Final results of the VANCO Trial need to be awaited for conclusive data on the efficacy of vancomycin for SSI prevention and its impact on wound healing.

Anesthesia modality does not affect clinical outcomes of intra-arterial vasodilator treatment in patients with symptomatic cerebral vasospasms.

Background: Delayed cerebral ischemia and cerebral vasospasm remain the leading causes of poor outcome in survivors of aneurysmal subarachnoid hemorrhage. Refractory cerebral vasospasms can be treated with endovascular vasodilator therapy, which can either be performed in conscious sedation or general anesthesia. The aim of this study is to compare the effect of the anesthesia modality on long-term clinical outcomes in patients undergoing endovascular vasodilator therapy due to cerebral vasospasm and hypoperfusion. Methods: Modified Rankin Scale (mRS) scores were retrospectively analyzed at time of discharge from the hospital and six months after aneurysmal subarachnoid hemorrhage. Additionally, National Institutes of Health Stroke Scale (NIHSS) was assessed 24 hours before, immediately before, immediately after, and 24 hours after endovascular vasodilator therapy, and at discharge and six months. Interventional parameters such as duration of intervention, choice and dosage of vasodilator and number of arteries treated were also recorded. Results: A total of 98 patients were included in this analysis and separated into patients who had interventions in conscious sedation, general anesthesia and a mix of both. Neither mRS at discharge nor at six months showed a significant difference for functionally independent outcomes (mRS 0-2) between groups. NIHSS before endovascular vasodilator therapy was significantly higher in patients receiving interventions in general anesthesia but did not differ anymore between groups six months after the initial bleed. Conclusion: This study did not observe a difference in outcome whether patients underwent endovascular vasodilator therapy in general anesthesia or conscious sedation for refractory cerebral vasospasms. Hence, the choice should be made for each patient individually.

How safe are elective craniotomies in elderly patients in neurosurgery today? A prospective cohort study of 1452 consecutive cases.

OBJECTIVE: With global aging, elective craniotomies are increasingly being performed in elderly patients. There is a paucity of prospective studies evaluating the impact of these procedures on the geriatric population. The goal of this study was to assess the safety of elective craniotomies for elderly patients in modern neurosurgery. METHODS: For this cohort study, adult patients, who underwent elective craniotomies between November 1, 2011, and October 31, 2018, were allocated to 3 age groups (group 1, < 65 years [n = 1008], group 2, ≥ 65 to < 75 [n = 315], and group 3, ≥ 75 [n = 129]). Primary outcome was the 30-day mortality after craniotomy. Secondary outcomes included rate of delayed extubation (> 1 hour), need for emergency head CT scan and reoperation within 48 hours after surgery, length of postoperative intensive or intermediate care unit stay, hospital length of stay (LOS), and rate of discharge to home. Adjustment for American Society of Anesthesiologists Physical Status (ASA PS) class, estimated blood loss, and duration of surgery were analyzed as a comparison using multiple logistic regression. For significant differences a post hoc analysis was performed. RESULTS: In total, 1452 patients (mean age 55.4 ± 14.7 years) were included. The overall mortality rate was 0.55% (n = 8), with no significant differences between groups (group 1: 0.5% [95% binominal CI 0.2%, 1.2%]; group 2: 0.3% [95% binominal CI 0.0%, 1.7%]; group 3: 1.6% [95% binominal CI 0.2%, 5.5%]). Deceased patients had a significantly higher ASA PS class (2.88 ± 0.35 vs 2.42 ± 0.62; difference 0.46 [95% CI 0.03, 0.89]; p = 0.036) and increased estimated blood loss (1444 ± 1973 ml vs 436 ± 545 ml [95% CI 618, 1398]; p <0.001). Significant differences were found in the rate of postoperative head CT scans (group 1: 6.65% [n = 67], group 2: 7.30% [n = 23], group 3: 15.50% [n = 20]; p = 0.006), LOS (group 1: median 5 days [IQR 4; 7 days], group 2: 5 days [IQR 4; 7 days], and group 3: 7 days [5; 9 days]; p = 0.001), and rate of discharge to home (group 1: 79.0% [n = 796], group 2: 72.0% [n = 227], and group 3: 44.2% [n = 57]; p < 0.001). CONCLUSIONS: Mortality following elective craniotomy was low in all age groups. Today, elective craniotomy for well-selected patients is safe, and for elderly patients, too. Elderly patients are more dependent on discharge to other hospitals and postacute care facilities after elective craniotomy. Clinical trial registration no.: NCT01987648 (clinicaltrials.gov).

Repetitive Computed Tomography Perfusion for Detection of Cerebral Vasospasm-Related Hypoperfusion in Aneurysmal Subarachnoid Hemorrhage.

BACKGROUND: Delayed cerebral infarction after aneurysmal subarachnoid hemorrhage (aSAH) still remains the leading cause of disability in patients that survive the initial ictus. It has been shown that computed tomography perfusion (CTP) imaging can detect hypoperfused brain areas. The aim of this study was to evaluate if a single acute CTP examination at time of neurologic deterioration is sufficient or if an additional baseline CTP increases diagnostic accuracy. METHODS: Retrospective analysis of acute and baseline (within 24 hours after aneurysm treatment) CTP examinations of patients with neurologic deterioration because of vasospasm-related hypoperfusion. Patients without clinical deterioration during the vasospasm period served as control subjects. The following CTP parameters were analyzed for predefined brain regions: time to drain (TTD), mean transit time, time to peak, cerebral blood flow, and volume. RESULTS: Thirty-three patients with and 23 without neurologic deterioration were included. Baseline CTP examination did not ameliorate diagnostic accuracy of the acute CTP examination in symptomatic patients. The same was true for interhemispheric comparison of perfusion parameters of the acute examination. The CTP parameter with the highest diagnostic yield was TTD of the symptomatic brain region (threshold value, 4.7 seconds; sensitivity, 97%; specificity, 96%). CONCLUSIONS: Acute CTP examination in case of suspected vasospasm-induced neurologic deterioration after aSAH has the highest diagnostic accuracy to detect misery perfusion. Additional baseline CTP is not needed. The most sensitive parameter to detect critically perfused brain areas is TTD.

Nimodipine-Induced Blood Pressure Changes Can Predict Delayed Cerebral Ischemia.

Background: Early diagnosis of delayed cerebral ischemia (DCI) in patients after aneurysmal subarachnoid hemorrhage (aSAH) still poses a leading problem in neurointensive care. The aim of this study was to analyze the effect of oral Nimodipine administration on systemic blood pressure in patients with evolving DCI compared to patients without DCI. Methods: Systolic (SBP), mean (MAP), and diastolic (DBP) blood pressures were analyzed at the time of Nimodipine administration and additionally 30, 60, and 120 min thereafter on days 1, 3, and 5 after aSAH. Additionally, the 24 h period preceding DCI and in patients without DCI day 10 after aSAH were analyzed. Statistical analysis was performed for SBP, MAP and DBP at time of Nimodipine administration and for the maximal drop in blood pressure after Nimodipine administration. Results: Thirty patients with aSAH were retrospectively analyzed with 17 patients developing DCI ("DCI") and 13 patients who did not ("Non-DCI"). DCI patients showed a more pronounced rise in MAP and DBP over the examined time period as well as a higher decrease in SBP following Nimodipine administration. A fall of 18 mmHg in SBP after Nimodipine administration showed a sensitivity of 82.4% and specificity of 92.3% for occurrence of DCI. Conclusion: An increase of MAP and DBP after aSAH and a heightened sensitivity to Nimodipine administrations may serve as additional biomarkers for early detection of evolving DCI.

Preliminary Results of Emergency Computed Tomography-Guided Ventricular Drain Placement-Precision for the Most Difficult Cases.

BACKGROUND: External ventricular drainage (EVD) catheter placement is one of the most commonly performed neurosurgical procedures. The study's objective was to compare a computed tomography (CT) bolt scan-guided approach for the placement of EVDs with conventional landmark-based insertion. METHODS: In this retrospective case-control study, we analyzed patients undergoing bolt-kit EVD catheter placement, either CT-guided or landmark-based, between 2013 and 2016. The CT bolt scan-guided approach was based on a dose-reduced CT scan after bolt fixation with immediate image reconstruction along the axis of the bolt to evaluate the putative insertion axis. If needed, angulation of the bolt was corrected and the procedure repeated before the catheter was inserted. Primary endpoint was the accuracy of insertion. Secondary endpoints were the overall number of attempts, duration of intervention, complication rates, and cumulative radiation dose. RESULTS: In total, 34 patients were included in the final analysis. In the group undergoing CT-guided placement, the average ventricle width was significantly smaller (P = 0.04) and average midline shift significantly more pronounced (P = 0.01). CT-guided placement resulted in correct positioning of the catheter in the ipsilateral frontal horn in all 100% of the cases compared with landmark-guided insertion (63%; P = 0.01). Application of the CT-guided approach increased the number of total CT scans (3.6 ± 1.9) and the overall radiation dose (3.34 ± 1.61 mSv) compared with the freehand insertion group (1.84 ± 2.0 mSv and 1.55 ± 1.66 mSv). No differences were found for the other secondary outcome parameters. CONCLUSIONS: CT-guided bolt-kit EVD catheter placement is feasible and accurate in the most difficult cases.

Early Postoperative Perils of Intraventricular Tumors: An Observational Comparative Study.

BACKGROUND: Early postoperative patient surveillance after removal of intraventricular tumors is often hindered by delayed awakening and prolonged somnolence. The objective of this study was to analyze the incidence of early critical postoperative events after elective craniotomy for intraventricular tumors in adults compared with extraventricular lesions. METHODS: An observational comparative study was conducted on adult patients who had undergone first-time elective craniotomy between November 2011 and August 2016. Patients were stratified into extraventricular lesions (group 1) and intraventricular tumors (group 2). The rates of late extubation, early postoperative seizures, emergency head computed tomography (CT) scans, and urgent surgical intervention within 48 hours and mortality within 30 days of surgery were analyzed from a prospective database. RESULTS: A total of 977 elective craniotomies were analyzed, including 951 (97.3%) in group 1 and 26 (2.7%) in group 2. Emergency CT scans were ordered significantly more frequently in group 2 (34.6% vs. 8.4%; odds ratio, 5.76; 95% confidence interval [CI], 2.49-13.35; P = 0.0002), and the incidence of urgent surgical intervention was significantly higher in group 2 (11.5% vs. 0.8%; odds ratio, 15.38; 95% CI, 3.83-61.72; P = 0.002). The main reason for urgent surgical intervention in group 2 was acute obstructive hydrocephalus. Overall surgical mortality after 30 days was 0.3% (3 cases in group 1, no cases in group 2). CONCLUSIONS: Intraventricular tumors are at significantly higher risk for early emergency head CT and urgent surgical intervention. This patient cohort might benefit from routine intraoperative and early postoperative imaging, as well as intraoperative extraventricular drain placement.

No Routine Postoperative Head CT following Elective Craniotomy--A Paradigm Shift?

INTRODUCTION: Patient management following elective cranial surgery often includes routine postoperative computed tomography (CT). We analyzed whether a regime of early extubation and close neurological monitoring without routine CT is safe, and compared the rate of postoperative emergency neurosurgical intervention with published data. METHODS: Four hundred ninety-two patients were prospectively analyzed; 360 had supra- and 132 had infratentorial lesions. Extubation within one hour after skin closure was aimed for in all cases. CT was performed within 48 hours only in cases of unexpected neurological findings. RESULTS: Four-hundred sixty-nine of the 492 patients (95.3%) were extubated within one hour, 20 (4.1%) within 3 hours, and three (0.6%) within 3 to 10 hours. Emergency CT within 48 hours was performed for 43/492 (8.7%) cases. Rate of recraniotomy within 48 hours for patients with postoperative hemorrhage was 0.8% (n = 4), and 0.8% (n = 4) required placement of an external ventricular drain (EVD). Of 469 patients extubated within one hour, 3 required recraniotomy and 2 required EVD placements. Of 23 patients with delayed extubation, 1 recraniotomy and 2 EVDs were required. Failure to extubate within one hour was associated with a significantly higher risk of surgical intervention within 48 hours (rate 13.0%, p = 0.004, odds ratio 13.9, 95% confidence interval [3.11-62.37]). DISCUSSION: Early extubation combined with close neurological monitoring is safe and omits the need for routine postoperative CT. Patients not extubated within one hour do need early CT, since they had a significantly increased risk of requiring emergency neurosurgical intervention. TRIAL REGISTRATION: ClinicalTrials.gov NCT01987648.