Effect of sugammadex on processed EEG parameters in patients undergoing robot-assisted radical prostatectomy.

BACKGROUND: Sugammadex has been associated with increases in the bispectral index (BIS). We evaluated the effects of sugammadex administration on quantitative electroencephalographic (EEG) and electromyographic (EMG) measures. METHODS: We performed a prospective observational study of adult male patients undergoing robot-assisted radical prostatectomy. All patients received a sevoflurane-based general anaesthetic and a continuous infusion of rocuronium, which was reversed with 2 mg kg-1 of sugammadex i.v. BIS, EEG, and EMG measures were captured with the BIS Vista™ monitor. RESULTS: Twenty-five patients were included in this study. Compared with baseline, BIS increased at 4-6 min (ß coefficient: 3.63; 95% confidence interval [CI]: 2.22-5.04; P<0.001), spectral edge frequency 95 (SEF95) increased at 2-4 min (ß coefficient: 0.29; 95% CI: 0.05-0.52; P=0.016) and 4-6 min (ß coefficient: 0.71; 95% CI: 0.47-0.94; P<0.001), and EMG increased at 4-6 min (ß coefficient: 1.91; 95% CI: 1.00-2.81; P<0.001) after sugammadex administration. Compared with baseline, increased beta power was observed at 2-4 min (ß coefficient: 93; 95% CI: 1-185; P=0.046) and 4-6 min (ß coefficient: 208; 95% CI: 116-300; P<0.001), and decreased delta power was observed at 4-6 min (ß coefficient: -526.72; 95% CI: -778 to -276; P<0.001) after sugammadex administration. Neither SEF95 nor frequency band data analysis adjusted for EMG showed substantial differences. None of the patients showed clinical signs of awakening. CONCLUSIONS: After neuromuscular block reversal with 2 mg kg-1 sugammadex, BIS, SEF95, EMG, and beta power showed small but statistically significant increases over time, while delta power decreased.

Development and Performance Evaluation of a Clinical Predictive Model to Estimate the Risk of Red Blood Cell Requirements in Brain Tumor Surgery.

BACKGROUND: The identification of factors associated with perioperative red blood cell (RBC) transfusion provides an opportunity to optimize the patient and surgical plan, and to guide perioperative crossmatch and RBC orders. We examined the association among potential bleeding risk factors and RBC requirements to develop a novel predictive model for RBC transfusion in patients undergoing brain tumor surgery. METHODS: This retrospective study included 696 adults who underwent brain tumor surgery between 2008 and 2018. Multivariable logistic regression with backward stepwise selection for predictor selection was used during modeling. Model performance was evaluated using area under the receiver operating characteristic curve, and calibration was evaluated with Hosmer-Lemeshow goodness-of-fit χ 2 -estimate. RESULTS: Preoperative hemoglobin level was inversely associated with the probability of RBC transfusion (odds ratio [OR]: 0.50; 95% confidence interval [CI]: 0.39-0.63; P <0.001). The need for RBC transfusion was also greater in patients who had a previous craniotomy (OR: 2.71; 95% CI: 1.32-5.57; P =0.007) and in those with larger brain tumor volume (OR: 1.01; 95% CI: 1.00-1.02; P =0.009). The relationship between number of planned craniotomy sites and RBC transfusion was not statistically significant (OR: 2.11; 95% CI: 0.61-7.32; P =0.238). A predictive model for RBC requirements was built using these 4 variables. The area under the receiver operating characteristic curve was 0.79 (95% CI: 0.70-0.87; P <0.001) showing acceptable calibration for predicting RBC transfusion requirements. CONCLUSIONS: RBC requirements in patients undergoing brain tumor surgery can be estimated with acceptable accuracy using a predictive model based on readily available preoperative clinical variables. This predictive model could help to optimize both individual patients and surgical plans, and to guide perioperative crossmatch orders.

Permanent renal sequelae secondary to drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome induced by quetiapine.

We describe a Caucasian man in his late 60s who was admitted to the intensive care unit (ICU) with a history of cardiogenic shock secondary to an acute myocardial infarction. The patient's baseline serum creatinine levels were 0.9-1 mg/dL. On day 7 of the admission treatment with quetiapine was initiated due to a delirium episode. The next day the patient developed an erythematous-maculopapular rash and fever, with eosinophilia in the blood count. Over the following days the patient experienced an acute deterioration of kidney function requiring continuous renal replacement therapy. The skin lesions and eosinophilia resolved after withdrawal of quetiapine and systemic steroid therapy was administered. The patient was discharged from the ICU with a serum creatinine level of 2.6 mg/dL. Three months later, blood tests showed no recovery of the kidney function. According to the Naranjo adverse drug reaction probability scale, this event would be classified as 'probable' DRESS syndrome and, based on the RegiSCAR scoring system, was classified as 'definite' DRESS syndrome.

Factors Associated with Headache and Nausea During Magnetic Resonance-Guided Focused Ultrasound for Tremor.

BACKGROUND: During magnetic resonance-guided focused ultrasound for essential or parkinsonian tremor, adverse events (headache, nausea/vomiting, or anxiety) may alter the outcome of the procedure despite being mostly transient and mild. OBJECTIVES: Our aim was to analyze the relationship between demographic, procedural, and anesthetic characteristics with magnetic resonance/ultrasound-related events. METHODS: This was a retrospective study at the Clinica Universidad de Navarra of patients undergoing thalamotomy with magnetic resonance-guided focused ultrasound between September 2018 and October 2019. The anesthesia protocol included headache and nausea/vomiting prophylaxis and rescue therapy. Dexmedetomidine was used for anxiolysis in some patients after thorough multidisciplinary assessment. RESULTS: A total of 123 patients were included. Headache was directly related to skull density ratio (P < 0.001) and skull thickness (P = 0.02). Patients with a skull density ratio less than 0.48 had 3 times the odds of experiencing moderate or severe headache (odds ratio [OR], 3.08; 95% confidence interval [CI], 1.21-7.82) and had a higher odds of aborting sonication due to pain. Sex was associated with increased nausea (P = 0.007). Women had 4 times the odds of nausea than men (OR, 4.4; 95% CI, 1.61-12.11). Dexmedetomidine did not reduce headache or nausea incidence. Patients who received dexmedetomidine had a higher number (P = 0.01) and total minutes of sonication (P = 0.01). CONCLUSIONS: Patients with lower skull density ratios and higher skull thicknesses could benefit from an aggressive analgesic prophylaxis. Women are more likely to experience nausea. Dexmedetomidine did not reduce headache and nausea, but increased the number and duration of sonications. Its exact effect on tremor is still unclear.

Effects of dexmedetomidine on subthalamic local field potentials in Parkinson's disease.

BACKGROUND: Dexmedetomidine is frequently used for sedation during deep brain stimulator implantation in patients with Parkinson's disease, but its effect on subthalamic nucleus activity is not well known. The aim of this study was to quantify the effect of increasing doses of dexmedetomidine in this population. METHODS: Controlled clinical trial assessing changes in subthalamic activity with increasing doses of dexmedetomidine (from 0.2 to 0.6 µg kg-1 h-1) in a non-operating theatre setting. We recorded local field potentials in 12 patients with Parkinson's disease with bilateral deep brain stimulators (24 nuclei) and compared basal activity in the nuclei of each patient and activity recorded with different doses. Plasma levels of dexmedetomidine were obtained and correlated with the dose administered. RESULTS: With dexmedetomidine infusion, patients became clinically sedated, and at higher doses (0.5-0.6 µg kg-1 h-1) a significant decrease in the characteristic Parkinsonian subthalamic activity was observed (P<0.05 in beta activity). All subjects awoke to external stimulus over a median of 1 (range: 0-9) min, showing full restoration of subthalamic activity. Dexmedetomidine dose administered and plasma levels showed a positive correlation (repeated measures correlation coefficient=0.504; P<0.001). CONCLUSIONS: Patients needing some degree of sedation throughout subthalamic deep brain stimulator implantation for Parkinson's disease can probably receive dexmedetomidine up to 0.6 µg kg-1 h-1 without significant alteration of their characteristic subthalamic activity. If patients achieve a 'sedated' state, subthalamic activity decreases, but they can be easily awakened with a non-pharmacological external stimulus and recover baseline subthalamic activity patterns in less than 10 min. CLINICAL TRIAL REGISTRATION: EudraCT 2016-002680-34; NCT-02982512.

Breath-Hold Induced Cerebrovascular Reactivity Measurements Using Optimized Pseudocontinuous Arterial Spin Labeling.

A pseudocontinuous arterial spin labeling (PCASL) sequence combined with background suppression and single-shot accelerated 3D RARE stack-of-spirals was used to evaluate cerebrovascular reactivity (CVR) induced by breath-holding (BH) in ten healthy volunteers. Four different models designed using the measured change in PETCO2 induced by BH were compared, for CVR quantification. The objective of this comparison was to understand which regressor offered a better physiological model to characterize the cerebral blood flow response under BH. The BH task started with free breathing of 42 s, followed by interleaved end-expiration BHs of 21 s, for ten cycles. The total scan time was 12 min and 20 s. The accelerated readout allowed the acquisition of PCASL data with better temporal resolution than previously used, without compromising the post-labeling delay. Elevated CBF was observed in most cerebral regions under hypercapnia, which was delayed with respect to the BH challenge. Significant statistical differences in CVR were obtained between the different models in GM (p < 0.0001), with ramp models yielding higher values than boxcar models and between the two tissues, GM and WM, with higher values in GM, in all the models (p < 0.0001). The adjustment of the ramp amplitude during each BH cycle did not improve the results compared with a ramp model with a constant amplitude equal to the mean PETCO2 change during the experiment.

Recovery time after oral and maxillofacial ambulatory surgery with dexmedetomidine: an observational study.

OBJECTIVES: To evaluate the relationship between pharmacokinetic descriptors of dexmedetomidine (predicted area under the curve during the procedure, predicted plasma level at the end of the procedure, and duration of procedure) and sedation depth (proportion of time with bispectral index < 85 during the procedure) with recovery time after ambulatory procedures. MATERIALS AND METHODS: Clinical observational study of patients undergoing oral and maxillofacial ambulatory surgery with dexmedetomidine as sole sedative agent. Patients received a loading dose of dexmedetomidine (0.25-1 µg kg-1) followed by a maintenance infusion (0.2-1.4 µg kg-1 h-1) to keep a bispectral index < 85 until 5 min before the end of the procedure, and were transferred to a post-anesthesia care unit until criteria for discharge were met. RESULTS: Data from 75 patients was analyzed. Sedation depth was directly associated with recovery time (Pearson correlation coefficient [r] = 0.26; p = 0.024). Around 7% of the variation in recovery time was explained by the proportion of time with bispectral index < 85. No association with procedure duration (r = 0.01; p = 0.9), predicted area under the curve (r = 0.1; p = 0.4), or predicted plasma level of dexmedetomidine at the end of the procedure (r = 0.12; p = 0.3) with recovery time was observed. CONCLUSIONS: Sedation depth with dexmedetomidine could play a role in increasing recovery time after oral and maxillofacial ambulatory surgery. In our study, the pharmacokinetic descriptors of dexmedetomidine did not seem to influence recovery time. CLINICAL RELEVANCE: Sedation depth with dexmedetomidine could play a role in increasing recovery time after ambulatory procedures.

Effect of Dexmedetomidine and Propofol on Basal Ganglia Activity in Parkinson Disease: A Controlled Clinical Trial.

BACKGROUND: Deep brain stimulation electrodes can record oscillatory activity from deep brain structures, known as local field potentials. The authors' objective was to evaluate and quantify the effects of dexmedetomidine (0.2 µg·kg·h) on local field potentials in patients with Parkinson disease undergoing deep brain stimulation surgery compared with control recording (primary outcome), as well as the effect of propofol at different estimated peak effect site concentrations (0.5, 1.0, 1.5, 2.0, and 2.5 µg/ml) from control recording. METHODS: A nonrandomized, nonblinded controlled clinical trial was carried out to assess the change in local field potentials activity over time in 10 patients with Parkinson disease who underwent deep brain stimulation placement surgery (18 subthalamic nuclei). The relationship was assessed between the activity in nuclei in the same patient at a given time and repeated measures from the same nucleus over time. RESULTS: No significant difference was observed between the relative beta power of local field potentials in dexmedetomidine and control recordings (-7.7; 95% CI, -18.9 to 7.6). By contrast, there was a significant decline of 12.7% (95% CI, -21.3 to -4.7) in the relative beta power of the local field potentials for each increment in the estimated peak propofol concentrations at the effect site relative to the control recordings. CONCLUSIONS: Dexmedetomidine (0.2 µg·kg·h) did not show effect on local field potentials compared with control recording. A significant deep brain activity decline from control recording was observed with incremental doses of propofol.

Factors Associated with Tremor Changes during Sedation with Dexmedetomidine in Parkinson's Disease Surgery.

INTRODUCTION: Dexmedetomidine is an α2-agonist recently proposed as a potentially ideal drug for sedation during the surgical treatment of Parkinson's disease (PD). This report documents the incidence of changes in motor symptoms (especially tremor) in PD patients sedated with dexmedetomidine for deep brain stimulation or ablation procedures. METHODS: We reviewed a retrospective cohort of 22 patients who underwent surgery for PD with dexmedetomidine sedation at a single institution from 2010 to 2014. A logistic regression analysis was performed to analyze possible confounding factors. RESULTS: 14 cases of tremor reduction or suppression were recorded (cumulative incidence: 63.6%; 95% CI: 40.7-82.8). No association could be identified between loading dose, ß-blocker use and preoperative total Unified Parkinson's Disease Rating Scale III, with tremor changes. The maintenance dose of dexmedetomidine was higher in patients who did not experience changes [median and range for patients with and without tremor alteration 0.75 (0.2-1.0) and 1.0 µg × kg(-1) × h(-1) (0.7-1.4), respectively; p = 0.021]. CONCLUSION: Dexmedetomidine provides adequate sedation during surgery for PD, but it might affect motor signs making intraoperative testing difficult or even impossible. Dosage appears not to be the determining factor in motor changes, whose cause remains unclear.

Safety Profile of 5-Aminolevulinic Acid as a Surgical Adjunct in Clinical Practice: A Review of 207 Cases From 2008 to 2013.

BACKGROUND: 5-Aminolevulinic acid (5-ALA) is used for brain tumor identification during surgery through fluorescence. Its use is linked to side effects such as photodermatosis, anemia, or plaquetopenia. Many institutions take very strict precautions to prevent them. Our hospital's protocol mandates avoidance of direct sunlight during the first 24 hours only. METHODS: Retrospective cohort observational study of 207 consecutive patients who underwent 5-ALA-guided brain tumor resection between 2008 and 2013, and compared with a control group of 53 patients without 5-ALA. RESULTS: No skin reaction was reported. No difference was found in hemoglobin or platelet level comparisons at different points in time. There was no difference in trends within groups. Mean duration of surgery was longer in the 5-ALA group; the subgroup of patients undergoing their first surgery had a positive correlation with lower hemoglobin levels. In postoperative magnetic resonance imaging, patients in the 5-ALA group had a lower percentage of residual bleeding (19% of all patients; 17.9% in 5-ALA group and 22.7% in non-ALA [P=0.04]). Eight patients in the 5-ALA group required blood transfusion (3.9%), compared with 2 in the control group (3.8%). Four patients in the 5-ALA group required reintervention in the first 48 hours due to bleeding, although none had platelets <150,000/mL. CONCLUSIONS: Significant side effects appear to be uncommon. Blood count changes are likely multifactorial; surgical time may account for it partially, whereas 5-ALA role is not clear and may not be significant.

Risks factors and regression model for risk calculation of anesthesiologic intervention in topical and intracameral cataract surgery.

PURPOSE: To determine risk factors for anesthesiologist intervention during routine cataract surgery performed with topical and intracameral anesthesia and establish a regression model to identify high-risk patients. SETTING: Department of Ophthalmology, Clínica Universidad de Navarra, Pamplona, Spain. DESIGN: Prospective case series. METHODS: After cataract surgery at an ambulatory surgical center, anesthesia personnel completed a questionnaire to determine adverse medical events and risk factors related to anesthesiologist intervention. A Poisson regression model was used to calculate the interventional risks. Bootstrapping was performed for internal model validation. RESULTS: Of the 1010 cases, 50 (4.95%) required anesthesiologist intervention. Univariate analysis identified an association between anesthesiologist intervention and hypertension (P<.001), psychiatric history (P=.002), initial systolic blood pressure (P<.001), surgical duration (P=.001), and diabetes (P=.018). Scores were obtained using the following proposed regression model equation: (-8.68 + 0.33 × sex [men, 0; women, 1] + -0.02 × age [years] + 0.68 × hypertensive history [no, 0; yes, 1] + 1.18 × psychiatric background [no, 0; yes, 1] + 0.04 × initial systolic blood pressure [mm Hg]). The area under the receiver-operating curve was 0.803 (95% confidence interval [CI], 0.721-0.886). The area under the curve found in the validation method was 0.813 (95% CI, 0.727-0.887). CONCLUSION: Hypertension was the main risk factor for anesthesiologist intervention. The regression model discriminated between patients at lower and higher risk for intraoperative intervention for monitored anesthesia care. The probability of anesthesiologist intervention was 11.7 times higher when the model obtained a high score. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.