Anh T. Nguyen

Awake craniotomy for gliomas in a high-field intraoperative magnetic resonance imaging suite: analysis of 42 cases

OBJECTIVES The object of this study was to describe the experience of combining awake craniotomy techniques with high-field (1.5 T) intraoperative MRI (iMRI) for tumors adjacent to eloquent cortex. METHODS From a prospective database the authors obtained and evaluated the records of all patients who had undergone awake craniotomy procedures with cortical and subcortical mapping in the iMRI suite. The integration of these two modalities was assessed with respect to safety, operative times, workflow, extent of resection (EOR), and neurological outcome. RESULTS Between February 2010 and December 2011, 42 awake craniotomy procedures using iMRI were performed in 41 patients for the removal of intraaxial tumors. There were 31 left-sided and 11 right-sided tumors. In half of the cases (21 [50%] of 42), the patient was kept awake for both motor and speech mapping. The mean duration of surgery overall was 7.3 hours (range 4.0-13.9 hours). The median EOR overall was 90%, and gross-total resection (EOR ≥ 95%) was achieved in 17 cases (40.5%). After viewing the first MR images after initial resection, further resection was performed in 17 cases (40.5%); the mean EOR in these cases increased from 56% to 67% after further resection. No deficits were observed preoperatively in 33 cases (78.5%), and worsening neurological deficits were noted immediately after surgery in 11 cases (26.2%). At 1 month after surgery, however, worsened neurological function was observed in only 1 case (2.3%). CONCLUSIONS There was a learning curve with regard to patient positioning and setup times, although it did not adversely affect patient outcomes. Awake craniotomy can be safely performed in a high-field (1.5 T) iMRI suite to maximize tumor resection in eloquent brain areas with an acceptable morbidity profile at 1 month.

Preoperative statin use is not associated with improvement in survival after glioblastoma surgery

Cohort studies have suggested that the use of statins is associated with decreased risk of glioma formation and mortality. Here, a cohort of patients with glioblastoma multiforme (GBM) was analyzed to further investigate associations between preoperative use of statins and recurrence, and progression free and overall survival. Patients who had surgery for GBM (N=284) were followed up for a median of 18.1months. Seventy-eight patients were taking statins preoperatively while the rest were not. Cox proportional hazards models adjusted for several covariates of interest were applied before and after propensity score matching. Compared with statin users, those not taking the lipid-lowering drugs had similar progression free survival before (hazard ratio [HR] 0.94, 95% confidence interval [CI] 0.70-1.26; p=0.68) and after propensity score matching (HR 0.95, 95% CI 0.67-1.35; p=0.68). Mortality was similar between both groups of patients before (HR 0.94, 95% CI 0.70-1.22; p= 0.73) and after propensity score matching (HR 1.13, 95% CI 0.78-1.64; p=0.49). Age and dexamethasone use were independent prognostic factors of survival. Contrary to previously published evidence, this study could not find an association between preoperative statin use and longer survival in GBM patients. Due to the small number of patients and retrospective nature of the study, further work is needed to understand the role of perioperative statins in GBM patients.

Association Between Perioperative Hyperglycemia and Survival in Patients With Glioblastoma.

Background: Several studies have examined the association between hyperglycemia in the first 10 to 12 weeks following surgery and postoperative survival in glioblastoma multiforme (GBM) patients. We hypothesize that episodes of hyperglycemia before, during and/or following surgery for primary GBM are independent predictors of disease progression and mortality. Materials and Methods: A total of 162 adult patients were included in the analysis. All patients received adjuvant temozolamide. The progression free survival (PFS) and overall survival (OS) rates at 1 and 5 years were analyzed using different glycemic cutoff values. Multivariate analyses were conducted to test the association between preoperative, intraoperative and postoperative hyperglycemia with PFS and OS. Results: Kaplan-Meier curves revealed a trend toward increased PFS and OS with lower glucose concentrations with the exception of glucose concentrations >180 mg/dL in the intraoperative/postoperative day 0 time period. Univariate analysis of blood glucose levels did not demonstrate a statistically significant effect on PFS in any time period, however hyperglycemia was statistically significant for OS in the preoperative time period. Although, multivariate analysis showed no statistically significant association with hyperglycemia on PFS, a statistically significant decrease in OS was seen for plasma glucose concentrations >112 mg/dL (P=0.01) and >180 mg/dL (P=0.01) in the preoperative period. There was a decreasing effect on OS with blood glucose concentrations greater than the median in multiple time periods (P=0.02). Conclusions: Preoperative hyperglycemia is associated with poor OS after GBM surgery.

The use of isoflurane and desflurane as inhalational agents for glioblastoma surgery. A survival analysis.

BACKGROUND Several studies have examined the impact of anesthetics on cancer recurrence. Isoflurane but not desflurane has protumoral effects. We hypothesize the use of isoflurane but not desflurane during surgery for primary GBM is an independent predictor of disease progression and mortality. METHODS 378 adult patients were included in the study. The progression free survival (PFS) and overall survival (OS) rates at 1 and 5years were compared in patients who had either desflurane or isoflurane alone or in combination with propofol infusion. Multivariate analyses were conducted to test the association between preoperative, intraoperative and postoperative hyperglycemia with PFS and OS. RESULTS Kaplan-Meier curves demonstrated similar survival in patients who had either desflurane or isoflurane. The use of a propofol infusion during surgery did not affect survival. Univariate analysis demonstrated that age, body mass index and the adjusted Charlson comorbidity score were associated with reduced survival. The multivariate analysis confirmed that age and BMI but not the type volatile anesthetic use were independent prognostic factors for PFS (HR, 95%CI: 1.07, 0.85-1.37, 9=0.531) and OS (HR, 95%CI: 1.13, 0.86-1.48, p=0.531). CONCLUSION The use of isoflurane or desflurane during GBM surgery is not associated with reduced PFS or OS.

Intraoperative serum lactate is not a predictor of survival after glioblastoma surgery

BACKGROUND Cancer cells can produce lactate in high concentrations. Two previous studies examined the clinical relevance of serum lactate as a biomarker in patients with brain tumors. Patients with high-grade tumors have higher serum concentrations of lactate than those with low-grade tumors. We hypothesized that serum lactic could be used of biomarker to predictor of survival in patients with glioblastoma (GB). METHODS This was a retrospective study. Demographic, lactate concentrations and imaging data from 275 adult patients with primary GB was included in the analysis. The progression free survival (PFS) and overall survival (OS) rates were compared in patients who had above and below the median concentrations of lactate. We also investigated the correlation between lactate concentrations and tumor volume. Multivariate analyses were conducted to test the association lactate, tumor volume and demographic variables with PFS and OS. RESULTS The median serum concentration of lactate was 2.3mmol/L. A weak correlation was found between lactate concentrations and tumor volume. Kaplan-Meier curves demonstrated similar survival in patients with higher or lower than 2.3mmol/L of lactate. The multivariate analysis indicated that the intraoperative levels of lactate were not independently associated with changes in survival. On another hand, a preoperative T1 volume was an independent predictor PFS (HR 95%CI: 1.41, 1.02-1.82, p=0.006) and OS (HR 95%CI: 1.47, 1.11-1.96, p=0.006). CONCLUSION This retrospective study suggests that the serum concentrations of lactate cannot be used as a biomarker to predict survival after GB surgery. To date, there are no clinically available serum biomarkers to determine prognosis in patients with high-grade gliomas. These tumors may produce high levels of lactic acid. We hypothesized that serum lactic could be used of biomarker to predictor of survival in patients with glioblastoma (GB). In this study, we collected perioperative and survival data from 275 adult patients with primary high-grade gliomas to determine whether intraoperative serum acid lactic concentrations can serve as a marker of prognosis. The median serum concentration of lactate was 2.3mmol/L. Our analysis indicated the intraoperative levels of lactate were not independently associated with changes in survival. This retrospective study suggests that the serum concentrations of lactate cannot be used as a biomarker to predict survival after GB surgery.

319: REFRACTORY HYPOXEMIA IN ACUTE RESPIRATORY DISTRESS SYNDROME: SYSTEMATIC REVIEW OF DIAGNOSTIC CRITERIA.

Crit Care Med 2015 • Volume 43 • Number 12 (Suppl.) to identify risk factors associated with multiple admissions. Methods: This was a case-control study of cancer patients admitted to the ICU between Jan 2009 and Dec 2013. The case group consisted of patients with more than one ICU admission during the study period, while the control group was patients with only one ICU admission. We determined the number of ICU admissions per patient and the time between those admissions. In addition, we recorded the patient characteristics and ICU mortality. We performed univariate analysis and logistic multivariate analysis to identify factors associated with multiple admissions. In addition, logistic regression analysis was performed to evaluate the association between multiple admissions and mortality and to determine the risk of mortality associated with each admission. Results: Over the study period, 2439 patients were admitted to the ICU and among those 620 (25.4%) patients had more than one admission, with an average of 2 admissions per patient, after a median of 31 days from their initial ICU admission. The most common readmission diagnosis were sepsis (25%), and respiratory distress (24.5%). Hematologic malignancy (OR 1.71; CI 1.39–2.1) and having received cancer-related therapies (OR 1.79; CI 1.28–2.51) were associated with multiple ICU admissions. Multiple admissions were associated with increased ICU mortality (OR 1.42, 95%CI 1.2–1.7) and with each ICU admission, the OR of mortality increased by 1.194 (95%CI 1.07–1.33).Conclusions: About one-fourth of cancer patients admitted to the ICU required readmission to the ICU. Hematologic malignancy and having received cancer-related therapies were associated with multiple ICU admissions. Multiple ICU admissions were associated with increased mortality.

CRITICALLY ILL CANCER PATIENTS ARE NOT CONSISTENTLY HYPERCOAGULABLE AFTER CRANIOTOMY.: 192-M

INTRODUCTION Recent reports using thrombelastography have suggested that neurosurgical patients develop a hypercoagulable state in the postoperative period. Since venous thromboembolism is a potentially life threatening complication in these patients, we studied a similar population in our institution. METHODS We conducted a prospective pilot study to evaluate postoperative coagulation changes in critically ill cancer patients after craniotomy. Data collected included demographics, diagnoses, severity of illness, all hematological information (coagulation tests included conventional and TEG), therapies, and complications. Analysis included descriptive statistics, and multivariate regression analysis. RESULTS Eleven patients were included in the study. Mean age was 52 +/- 17 years, BMI 28 +/- 6.5, APACHE II and SOFA scores were 11.18 +/- 5.0 and 3.82 +/- 1.6 respectively. The Coagulation Index (CI), which is derived from the measured values of R, K, MA, and alpha angle was 1.22 +/- 3.5, R 4.2 +/- 1.6, K 2.0 +/- 2.1, MA 60.78 +/- 5.97, and alpha angle 66.88 +/- 14.9; while the Thrombodynamic Potential Index (TPI), which is derived from the measured values of K and MA only was 32.48 +/- 21. The CI correlated significantly with R, K, alpha angle, MA, TMA, TPI, PMA, E, A30 and A60 but not with the PTT, INR, or SOFA and APACHE II scores. One patient was hypocoagulable by CI and TPI values; in contrast, nine patients were hypercoagulable by TPI but only one by CI. There were no cases of VTE. CONCLUSIONS Hypercoagulability as defined by the CI was not a common finding in this study. Although the TPI indicated hypercoagulability in a large number of patients, we do not believe it is a good tool to assess the patients clotting status or predictor of thrombosis because in contrast to the CI, it does not take into account the enzymatic portions of the clotting cascade. A larger TEG study is warranted to determine the clinical significance of these changes in this and other populations.