Standard Anesthesia Monitoring Research Articles

Unexpected Events That Occur in Patients on the Day of Surgery: A Single-center, Prospective Observational Study

PurposeThe purpose of this study is to investigate the reasons for case cancellations on the day of surgery and determine the rates of unexpected events and case cancellations. DesignThis is a prospective, cross-sectional study conducted at a single hospital. MethodsThe patients’ reasons for surgical cancellation were classified as preventable or nonpreventable. Patient data were obtained in the operating room after standard anesthesia monitoring by anesthesiologists. Unexpected problems that emerged in patients and cases canceled due to these problems were recorded. We evaluated blood pressure values according to the American College of Cardiology and American Heart Association guidelines. FindingsElective surgery was planned for a total of 4,287 patients. The incidence of an unexpected event detected on the day of surgery was 5.8% (n = 250), and the case cancellation rate was 2.16%. Examination or medical condition-related factors (n = 78, 83.9%) were the most common reason for case cancellation. Among the 250 unexpected events, patients with undiagnosed hypertension were in the majority (n = 130, 52%). Severe hypertension was observed in 30 patients (12%) who were previously diagnosed with hypertension, and the surgery was canceled in 25 (83.3%) of these (P < .001). ConclusionsPreventable causes (60.2%) were more common than nonpreventable ones among case cancellations. Our findings showed that many patients had high blood pressure and were unaware of this condition. Our study allowed referral of patients to a cardiologist to begin the follow-up process. Additionally, our study highlights the need for adequate preoperative anesthesia preparation and comprehensive nursing care.

Decrease of the peak heights of EEG bicoherence indicated insufficiency of analgesia during surgery under general anesthesia.

Studies show that the two peak heights of electroencephalographic bicoherence (pBIC-high, pBIC-low) decrease after incision and are restored by fentanyl administration. We investigated whether pBICs are good indicators for adequacy of analgesia during surgery. After local ethical committee approval, we enrolled 50 patients (27-65years, ASA-PS I or II) who were scheduled elective surgery. Besides standard anesthesia monitors, to assess pBICs, we used a BIS monitor and freeware Bispectrum Analyzer for A2000. Fentanyl 5µg/kg was completely administered before incision, and anesthesia was maintained with sevoflurane. After skin incision, when the peak of pBIC-high or pBIC-low decreased by 10% in absolute value (named LT10-high and LT10-low groups in order) or when either peak decreased to below 20% (BL20-high and BL20-low groups), an additional 1g/kg of fentanyl was administered to examine its effect on the peak that showed a decrease. The mean values and standard deviation for pBIC-high 5min before fentanyl administration, at the time of fentanyl administration, and 5min after fentanyl administration for LT10-high group were 39.8% (10.9%), 26.9% (10.5%), and 35.7% (12.5%). And those for pBIC-low for LT10-low group were 39.5% (6.0%), 26.8% (6.4%) and 35.0% (7.0%). Those for pBIC-high for BL20-high group were 26.3% (5.6%), 16.5% (2.6%), and 25.7% (7.0%). And those for pBIC-low for BL20-low group were 26.7% (4.8%), 17.4% (1.8%) and 26.9% (5.7%), respectively. Meanwhile, at these trigger points, hemodynamic parameters didn't show significant changes. Superior to standard anesthesia monitoring, pBICs are better indicators of analgesia during surgery. Clinical trial Number and registry URL: UMIN ID: UMIN000042843 https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno = R000048907.

Accuracy and role of consumer facing wearable technology for continuous monitoring during endoscopic procedures.

Consumer facing wearable devices capture significant amounts of biometric data. The primary aim of this study is to determine the accuracy of consumer-facing wearable technology for continuous monitoring compared to standard anesthesia monitoring during endoscopic procedures. Secondary aims were to assess patient and provider perceptions of these devices in clinical settings. Patients undergoing endoscopy with anesthesia support from June 2021 to June 2022 were provided a smartwatch (Apple Watch Series 7, Apple Inc., Cupertino, CA) and accessories including continuous ECG monitor and pulse oximeter (Qardio Inc., San Francisco, CA) for the duration of their procedure. Vital sign data from the wearable devices was compared to in-room anesthesia monitors. Concordance with anesthesia monitoring was assessed with interclass correlation coefficients (ICC). Surveys were then distributed to patients and clinicians to assess patient and provider preferences regarding the use of the wearable devices during procedures. 292 unique procedures were enrolled with a median anesthesia duration of 34 min (IQR 25-47). High fidelity readings were successfully recorded with wearable devices for heart rate in 279 (95.5%) cases, oxygen in 203 (69.5%), and respiratory rate in 154 (52.7%). ICCs for watch and accessories were 0.54 (95% CI 0.46-0.62) for tachycardia, 0.03 (95% CI 0-0.14) for bradycardia, and 0.33 (0.22-0.43) for oxygen desaturation. Patients generally felt the devices were more accurate (56.3% vs. 20.0% agree, p < 0.001) and more permissible (53.9% vs. 33.3% agree, p < 0.001) to wear during a procedure than providers. Smartwatches perform poorly for continuous data collection compared to gold standard anesthesia monitoring. Refinement in software development is required if these devices are to be used for continuous, intensive vital sign monitoring.

The AccuFlow sensor: a novel digital health tool to assess intrapartum blood loss at cesarean delivery.

During obstetric hemorrhage, peripheral vasoconstriction maintains heart rate and blood pressure until compensatory mechanisms are overwhelmed and patients deteriorate rapidly. Real-time perfusion measurements could quantify vasoconstriction, improving early recognition of hemorrhage and facilitating early intervention to reduce morbidity and mortality. The AccuFlow device makes rapid, non-invasive, quantitative measurements of perfusion, but has not been studied for hemorrhage detection or used in surgical settings. This study evaluated feasibility, tolerability, and preliminary efficacy of the AccuFlow for assessment of blood loss at cesarean delivery (CD). In this pilot study, sensors were applied to the wrist, forearm, bicep, and chest wall of 25 patients undergoing scheduled CD. Postoperatively, sensors were removed and patients rated the AccuFlow and the standard anesthesia monitoring equipment on a validated comfort rating scale for wearable computers (CRS). Blood loss was estimated by the surgical team (EBL) and calculated from change in hematocrit, weight, and height (CBL). CRS scores were compared via Wilcoxon signed ranks tests. Coefficients of correlation between sensor readings and CBL, and between EBL and CBL, were compared using Fisher's R-to-z transformation. There were no safety events; no participants requested device removal. CRS ratings of the AccuFlow andthe standard monitoring equipment were similar (7.2vs. 8.8, p=0.25). Change in wrist perfusion from delivery to dressing placement was more strongly correlated with CBL than was EBL (R=-0.48 vs. R=0.087, p=0.03). The AccuFlow sensor is well-tolerated and shows promise in detecting intrapartum hemorrhage, though larger studies are needed.

Endocrine and metabolic monitoring for anesthesia care in orthopedic trauma surgery on the lower extremities of children: prospective comparative study

BACKGROUND: Standard anesthesia monitoring during surgery only indirectly allows us to estimate achieving an effective level of analgesia sufficient to protect the patient from surgical trauma. Recently, studies have analyzed cortisol, glucose, and lactate levels during surgery in children and adults; however, data presented remain inconsistent.&#x0D; OBJECTIVE: This study aimed to conduct a prospective comparative analysis of endocrine metabolic dynamic rates in orthopedic trauma surgery on the lower extremities of children.&#x0D; MATERIALS AND METHODS: The study included 39 children who underwent orthopedic trauma surgery. They were divided into two groups: group 1 (n=17) underwent multicomponent balanced general anesthesia, and group 2 (n=22) received combined anesthesia (multicomponent balanced general anesthesia combined with regional blockade of the sciatic and femoral nerves). The dynamics of cortisol, glucose, and lactate indicators at three stages of the perioperative period, total amount of fentanyl, and need for an inhalation anesthetic were examined.&#x0D; RESULTS: Indicators of cortisol, glucose, and lactate in mixed venous blood during surgery did not exceed the age norm in both groups. In group 1, cortisol, glucose, and lactate levels did not statistically differ at all stages of the study. In group 2, cortisol and lactate levels increased at the fifth stage (traumatic stage) of surgery, and lactate levels increased in the sixth stage (end of surgery). In intergroup comparison, the lactate level at the traumatic stage of surgery was higher in group 1 than in group 2 (p=0.048). Cortisol and glucose levels at the stages of the study did not differ significantly. The total amount of fentanyl for pain relief in group 1 was 4.1 [3.3; 5.0] g/kg, which was 8.2 times higher than that in group 2, with 0.5 [0.4; 0.53] g/kg (p 0.0001).&#x0D; CONCLUSION: Both anesthesia methods ensure stable levels of cortisol, glucose, and lactate, and adequate level of analgesia at all stages of surgery; however, the use of a conduction blockade as a component of combined anesthesia provides more pronounced antinociceptive protection and reduces surgical stress in children.

Comparison of 4.5% Versus 8% Sevoflurane for Inhalational Induction in Adults

Background: Inhalational induction is a frequently used anesthetic technique in pediatric patients. However, it is less frequently used in adult patients undergoing surgery. General anesthesia can be induced either by intravenous injection or inhalation of anesthetic drugs. There are no established guidelines about the usage of 4.5% vs 8% sevoflurane for inhalation induction in adults undergoing elective day care surgery. Aim: To compare mean time to loss of eyelash reflex using 4.5% vs 8% sevoflurane for inhalational induction in adult patients undergoing elective day care surgery. Methodology: This randomized controlled trial was conducted in the department of anesthesia, Mayo Hospital Lahoreover a period of six months from June 2018 to December 2018. A total of 60 patients were enrolled in the study. We included adult patients aged 18-60 years of either gender and ASA status I &amp; II undergoing elective day care surgery. While, patients having history of adverse reaction to inhalational agents and those who were on chronic sedatives, antipsychotic treatment were excluded. Demographic data of age and gender were obtained along with their body weight, height and BMI. They were randomly divided into two study groups using lottery method. After routine pre-op check and attaching standard anesthesia monitoring, patients in group-A and group-B were given 4.5% sevoflurane &amp; 8% sevoflurane respectively at a fresh gas flow of 8 L/min of oxygen and they were instructed to take deep breaths while inhaling gas with help of face mask. Results: The mean age in 4.5% sevoflurane group was 42.27±11.83 years while in 8% sevoflurane group it was 45.43±12.76 years. In 4.5% sevoflurane group there were 12(40%) male and 18(60%) female cases while in 8% sevoflurane group there were 11(36.67%) male and 19(63.33%) female cases. The mean time to loss of eyelash reflex in 4.5% sevoflurane group was 88.57±6.71 seconds and in 8% sevoflurane group the mean time to loss eyelashes reflex was 67.87±5.90 seconds. The mean time to loss eyelashes reflex was statistically less in 8% sevoflurane group, with p-value 0.001. Conclusion: We concluded that mean time to loss eyelashes reflex was considerably lesser with8% sevoflurane when compared with 4.5% sevoflurane for inhalational induction in adult patients for elective day care surgery. Keywords: Inhalational induction, sevoflurane, eyelash reflex, day care surgery.

The AccuFlow Sensor: A Novel Tool to Assess Intrapartum Blood Loss

To 1) assess patient comfort with a wireless, cellular-capable heat flux sensor, the AccuFlow Sensor, during scheduled cesarean delivery, and 2) determine the most appropriate site at which to use the sensor to measure vasoconstriction as a proxy for intrapartum blood loss. Patients with a BMI of < 35kg/mˆ2 and hemoglobin ≥10.0g/dL undergoing scheduled cesarean were enrolled. Perfusion sensors were applied to the wrist, forearm, bicep, and chest prior to spinal anesthesia. Postoperatively, patients rated the tolerability of the sensors and standard anesthesia monitoring equipment on a validated comfort rating scale for wearable computers (CRS). Blood loss was estimated by the surgical team and also calculated by change in hematocrit adjusted for weight and height. Wilcoxon signed ranks tests were used to compare CRS scores. Correlations between calculated blood loss and surgical team estimates, and between calculated blood loss and sensor readings, were compared using Fisher’s R-to-z transformation. 25 patients were enrolled; none requested sensor removal. CRS scores were similar for the sensor and the standard anesthesia equipment (Table). Change in blood flow at all sites on the arm correlated with blood loss. Change in perfusion at the wrist was most strongly correlated with blood loss (R=-0.41, Figure). The sensor performed better than the surgical team at estimating blood loss (R=-0.41 vs R=0.087, p=0.043). In isolation, wrist perfusion at cesarean conclusion also correlated with blood loss (R=0.22), indicating that the device detects decreased perfusion in the absence of pre-hemorrhage measurements. The AccuFlow Sensor was well-tolerated, may estimate surgical blood loss more accurately than the surgical team, and shows promise to detect decreased perfusion in the absence of pre-hemorrhage readings. A larger trial is needed to assess the sensor’s ability to predict clinically important outcomes such as need for blood transfusion.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Curious Case of the Pretracheal Stethoscope

Curious Case of the Pretracheal Stethoscope

Havayolunun Uyanık Video Laringoskopik Değerlendirmesi Öngörülmeyeni Öngörmekte Yeni Araç Olabilir mi?: Randomize Çapraz Geçişli Çalışma

Objective: Even with worldwide acceptance and obedience to airway evaluation tests, there have not been enough tests performed to predict a difficult intubation with 100% accuracy. The Cochrane database published a review about the insufficiency of airway examination tests. For decades, anesthesiologists have tried to identify these issues. Material and Methods: After ethics committee approval and written informed consent had been obtained, 20 patients were enrolled to this prospective randomised study. All patients were oxygenated before and during the procedure. Standard anesthesia monitoring and 0.05 mg.kg-1 midazolam was administered intravenously. The nasopharynx was prepared with a topical 10% lidocaine spray then a continuous remifentanil infusion was given at a rate of 0.07 μ.kg.min-1 at least for 3 minutes. Awake videolaryngoscopy with Storz C-MAC, Storz D-Blade, McGrath MAC X-Blade and Airtraq was performed in random order to the same patient. Results: Two women denied participation and we analysed 18 patients. One patient did not allow the Airtraq to be inserted deeper and so we had 17 analyses for awake assessment for the Airtraq. Demographic and airway variables of patients were similar. The duration to obtain the optimal view was similar among the videolaryngoscopes. The comfort rating of patient and the observer were lower in the C-MAC (p<0.001). The Cormack-Lehane grades were worse in the C-MAC when compared to the others (p=0.006). Gag reflex occurred more in the Airtraq and the C-MAC videolaryngoscopes (p=0.007). Conclusion: Airtraq, McGrath MAC X-Blade, Storz D-Blade was superior to Storz C-MAC for awake videolaryngoscopic assessment of the airway as a new tool to predict a difficult laryngoscopy.

Effect of Priming Principle on Propofol Dose Required to Induce General Anesthesia

Objective: To compare the mean induction dose of Propofol to induce general anesthesia by conventional method versus mean induction dose after applying priming principle. Study Design and Setting: Randomized controlled trial at Operation theatre complex, Shalamar Hospital, Lahore from November 2016 to May 2017. Methods: A total of 100 patients aged 18-55 years were equally divided into control and study groups. After standard anesthetic monitoring, intravenous propofol was used for induction of general anesthesia by conventional method in Control (C) group and by applying Priming principle in Study (S) group. Total dose requirement of propofol was noted. Data was analyzed in SPSS version 20 and paired sample t-test was applied. P-value of &lt; 0.05 was considered as significant. Results: The mean induction dose of propofol was 70.90 ± 16.77 mg in study group (S) as compared to 94.60 ± 20.22 mg in the control group (C). The difference of mean induction dose in both groups was 23.7± 3.45 mg and thus p-value of 0.000. Conclusion: There was significant reduction of dose of propofol required to induce general anesthesia in elective surgical patient by applying priming principle

Benefits and boundaries of processed electroencephalography (pEEG) monitors when they do not concur with standard anesthetic clinical monitoring: lights and shadows.

Numerous clinical conditions that have a direct effect on electroencephalography (EEG) cerebral function could also directly influence brain function monitors (BFM) indices. There is no conventional comparator technology for BFM assessment. The conventional comparator technology used as a benchmark for assessing BFMs technologies chosen by the UK National Institute for Health and Care Excellence (NICE) to reflect the currently used standards in the National Health Service (NHS), was demarcated as "standard anesthetic clinical monitoring" and precisely defined as "the combination of routine clinical observation and electronic monitoring used in clinical practice to assess the adequacy of anesthesia." Because BFMs are EEG-derived parameters, all conditions that can "alter" the raw EEG signal would subsequently change BFM indices to reflect other unrelated EEG events of patient-dependent pathophysiologic perturbations. In many instances we are often confronted with disparate BFM values that do not concur with "standard anesthetic clinical monitoring". Changes in BFM indices during acute cerebral pathology would be highly beneficial to trained informed clinicians as it alerts to something they would not otherwise be aware was happening. This fact-based, citation-supported, narrative review article provides better understanding of BFMs' limitations through examining various published reports of all values that did not coincide with a "standard anesthetic clinical monitoring" whether arising from an underlying alteration of patients' own EEG or those due to shortcomings in the BFM design or performance. The notion of just "riding the numbers" seems to be not a good anesthesia practice; rather we should interpret these BFM indices within context and limitations.

Placement of TOF-Cuff\xae on the lower leg for neuromuscular and blood pressure monitoring during anesthetic induction for shoulder surgeries

PurposeThe aim of this study was to compare two devices for neuromuscular monitoring during anesthetic induction. TOF-Cuff® was installed on the lower leg stimulating the tibial nerve, while the more conventional TOF-Scan® was installed over the ulnar nerve at the wrist.MethodsTwenty adult patients were enrolled in this prospective, controlled study. Train-of-four (TOF) was recorded every 15 s until TOF ratio of 0%. Mean arterial blood pressure (MAP) was assessed with TOF-Cuff® and with standard anesthesia monitoring from the brachial artery. MAP was measured before and after anesthetic induction. Time to TOF ratio = 0% was compared with one-sample t test and Bland–Altman plots.ResultsPatients received 0.53 ± 0.09 mg atracurium per kg body weight intravenously. Mean time to TOF ratio = 0% was 150.8 s (± 43.7) for TOF-Scan®, and 174.4 s (± 42.7) for TOF-Cuff® (p = 0.1356). Bias was − 15.9 (95% confidence interval − 37.5 to 5.6) with 95% limits of agreement of − 95.2 to 63.3. Twenty-five percent of the patients had a technical issue with a TOF-Cuff® measurement. For MAP, mean difference was 1.4 (95% confidence interval − 2.4 to 5.2) with 95% limits of agreement of − 22.7 to 25.5.ConclusionThe time from administration of a common dose of atracurium to a TOF ratio of 0% assessed with TOF-Cuff® stimulating the tibial nerve compared to TOF-Scan® stimulating the ulnar nerve showed large limits of agreement in Bland–Altman analysis. There was a high failure rate with TOF-Cuff® measurements on the lower leg.

Changes in serum cortisol and blood glucose concentrations in anesthetized, pain-free dogs administered fentanyl

ObjectiveTo evaluate whether fentanyl administered at analgesic doses in pain-free anesthetized dogs increases the serum cortisol or blood glucose concentrations and is associated with postanesthetic dysphoria. Study designExperimental, blinded, randomized crossover. AnimalsA group of six adult research dogs. MethodsEach dog was anesthetized twice and was administered fentanyl or saline with a 15-day wash-out period. Treatment allocation was randomly assigned via a closed envelope technique. Cortisol and glucose concentrations were measured on arrival in the research room (TPRE), induction of general anesthesia (TIND), extubation (TEXT) and 1 hour after extubation (TPOST). Dogs were premedicated with methadone (0.1 mg kg−1) and carprofen (4 mg kg−1) intravenously (IV), anesthesia induced with propofol (4–6 mg kg−1) IV and maintained with isoflurane in oxygen. Standard anesthesia monitoring was performed throughout the experiment. Fentanyl (5 μg kg−1 over 90 seconds followed by 7.5 μg kg−1 hour −1) or an equivalent amount in mL of saline solution were administered IV for 60 minutes. TPRE behavior scores and recovery scores were evaluated using descriptive 4-point scales. Data from serum cortisol and blood glucose concentrations were analyzed with a Split Plot on time test, whereas recovery scores were analyzed using a Wilcox match-pairs signed rank test. Statistical significance was set at p < 0.05. ResultsThere were no significant increases in serum cortisol and blood glucose concentrations over time, and there were no differences between treatments. None of the dogs developed postanesthetic dysphoria with either treatment. Conclusions and clinical relevanceFentanyl, administered at analgesic doses to healthy, pain-free, anesthetized dogs, was not associated with significant changes in serum cortisol or glucose concentrations in the studied population.

ANALYSIS OF THE EFFICIENCY OF EXTENDED INTRA-OPERATING MONITORING IN PERFORMING COCHLEAR IMPLANTATIONS

Introduction. Cochlear implantation is a recognized treatment method for patients with severe and deep neurosensory hearing loss. To adjust the parameters of the speech processor of a cochlear implant (CI), the implementation of subjective techniques is not always possible, especially for younger patients. A good starting point for determining patient comfort levels during the initial connection of a speech processor is the intraoperatively obtained data of objective methods, one of which is the registration of an electrically induced stapedial reflex (EISR). Due to the marked effect of general anesthesia on the results of testing of CI and the lack of a universal anesthesiological protocol for this surgical intervention, the purpose of the study is to study the effectiveness of using extended intraoperative monitoring during testing of CI. Material and methods. The study included two groups, each consisting of 26 patients aged from 1 year to 15 years with a diagnosis of chronic sensorineural hearing loss. All children were installed CI delivered by company Med El (Austria). In the 1st group, data from medical records were analyzed retrospectively (anesthetic patient card and ESRT threshold values registration card during anesthesia and standard anesthesia monitoring volume). In the 2nd group of patients, intraoperative monitoring of anesthesia was extended by continuous evaluation of EEG (BIS-index) and indices of the degree of myoplegia. CI testing in this group was carried out in the recovery phase of neuro-muscular conductivity (4 TOF responses) and with BIS-index values from 60 to 80, which corresponded to sedation during drug sleep. Results. In the course of the work done in two groups of patients, the average values of intermediate points of the ESRT were analyzed, a comparative assessment of hemodynamic parameters at the main stages of the operation was carried out, and the optimal values of the minimum alveolar concentration of sevoflurane anesthetic and BIS index were determined for timely registration of the movement of stapedial muscle by the surgeon.

Propofol TCI Reductions Do Not Attenuate Significant Falls in Cardiac Output Associated With Anesthesia Induction and Knee-Chest Positioning in Spinal Surgery.

Induction of anesthesia and the knee-chest position are associated with hemodynamic changes that may impact patient outcomes. The aim of this study was to assess whether planned reductions in target-controlled infusion propofol concentrations attenuate the hemodynamic changes associated with anesthesia induction and knee-chest position. A total of 20 patients scheduled for elective lumbar spinal surgery in the knee-chest position were included. In addition to standard anesthesia monitoring, bispectral index and noninvasive cardiac output (CO) monitoring were undertaken. The study was carried out in 2 parts. In phase 1, target-controlled infusion propofol anesthesia was adjusted to maintain BIS 40 to 60. In phase 2, there were 2 planned reductions in propofol target concentration: (1) immediately after loss of consciousness-reduction calculated using a predefined formula, and (2) before positioning-reduction equal to the average percentage decrease in CO after knee-chest position in phase 1. Changes from baseline in CO and other hemodynamic variables following induction of anesthesia and knee-chest positioning were compared. Induction of anesthesia led to decreases of 25.6% and 19.8% in CO from baseline in phases 1 and 2, respectively (P<0.01). Knee-chest positioning resulted in a further decrease such that the total in CO reduction from baseline to 10 minutes after positioning was 38.4% and 46.9% in phases 1 and 2, respectively (P<0.01). There was no difference in CO changes between phases 1 and 2, despite the planned reductions in propofol during phase 2. There was no significant correlation between changes in CO and mean arterial pressure. Planned reductions in propofol concentration do not attenuate anesthesia induction and knee-chest position-related decreases in CO. The knee-chest position is an independent risk factor for decrease in CO. Minimally invasive CO monitors may aid in the detection of clinically relevant hemodynamic changes and guide management in anesthetized patients in the knee-chest position.

Use of a novel functional bed sheet to monitor heart rate and respiratory rate of six isoflurane-anesthetized dogs

Introduction: A functional bed sheet monitor is a novel technology that was used with standard anesthetic monitoring in six dogs to assess measurement of heart rate (HR) and respiratory rate (RR). The functional bed sheet contains a sensing thread that captures information by contact, and communicates with a computer and monitor for viewing data. The functional bed sheet has potential for recording HR and RR noninvasively in anesthetized dogs. This is proof of concept for new technology.

Challenges in Awake Craniotomy for Intrinsic Brain Tumors in Eloquent Cortex

Introduction: Surgical treatment of brain tumors in the eloquent areas has high risk of functional impairment like speech or motor. These tumors represent a unique challenge as most of the patients have a higher risk of treatment related complications. A wake craniotomy is a useful surgical approach to help to identify and preserve functional areas in the brain and maximizes tumor removal and minimizes complications. Methods: Selected patients admitted with intrinsic brain tumor between from July, 2011 to August, 2016 in the eloquent area of brain like speech or motor area were chosen for awake craniotomy. A retrospective analysis was done. A preoperative assessment was also done. These patients were presented with seizure and or progressive neurological deficit like speech or motor. A standard anesthesia monitoring was done during surgery. Long acting local anesthesia (Bupivacaine) was used for scalp block. The surgeries were performed in a state of asleep-awake-asleep pattern, keeping the patients fully awake during tumor removal. Propofol and Fentanyl was used as anesthetic agents which was completely withdrawn prior to tumor removal. The speech and motor functions were closely monitored clinically by verbal commands during tumor resection. No brain mapping was performed due to lack of resources. All patients underwent noncontrast computed tomogram head in the first post-operative day. Results: A total of 35 patients were included in the study. The oldest patient was 55 years and youngest being 24 years (mean 36 years). 20 (57.14 %) were females and 15(42.85 %) males. 20 (57.14%) patients presented with predominantly seizure disorders and rest with progressive neurological deficit like speech or motor. 30 (85.71%) patients were discharged on second post-operative day. Complications were encountered in 4 (11.42 %) patients who developed brain swelling intraoperatively and 5(14.28 %) deteriorated neurologically in the immediate post-operative period however managed successfully and discharged in a week’s time. 5(14.28%) patients require ICU/ HDU care for different reasons. There was no mortality during the hospital stay. Histopathology revealed 25 (71.42 %) patients as low grade glioma, 8 (22.85%) as high grade glioma and 2 (5.71%) of them were metastases. Conclusion: A wake Craniotomy is a safe surgical management for intrinsic brain tumors in the eloquent cortex although surgery and anesthesia is a challenge. It offers great advantage towards disease outcome. However long follow up and more studies are required.

Tracheal intubation in patients immobilized by a rigid collar: a comparison of GlideScope and an intubating laryngeal mask airway.

Intubation must be rapidly performed with the utmost care in cervical trauma patients. We present the first comparison of GlideScope and an intubating laryngeal mask airway (ILMA) regarding insertion and intubation times, intubation success rates, mucosal damage, need for optimization maneuvers, effects on hemodynamic changes, and postoperative minor complications in a simulated cervical injury with a Philadelphia cervical collar. Ethics committee approval and patient consent were obtained and 94 American Society of Anesthesiology physical status I or II patients were enrolled in this study. Following standard anesthesia monitoring and induction, the Philadelphia-type cervical collar was applied and patients were subsequently intubated with ILMA or GlideScope. The total intubation success rates were similar between the groups (96%). The insertion (14.9 ± 10 s vs. 21.9 ± 6.5 s, respectively; P < 0.001) and intubation (43.5 ± 13 s vs. 48.4 ± 11 s; P = 0.02) times for ILMA were longer than for GlideScope. The total intubation times for ILMA were longer than the intubation time for GlideScope (43.5 ± 13 s vs. 85.6 ± 13 s; P < 0.001). The mucosal damage was higher in the ILMA group (P = 0.04). The two airway devices increased the heart rate and mean arterial pressure after insertion compared with the postinduction values within groups. GlideScope is superior to ILMA in terms of lower insertion and intubation times and lower levels of mucosal damage in cervical collar-immobilized patients.

Monitoring Depth of Anesthesia Utilizing a Combination of Electroencephalographic and Standard Measures

For decades, monitoring depth of anesthesia was mainly based on unspecific effects of anesthetics, for example, blood pressure, heart rate, or drug concentrations. Today, electroencephalogram-based monitors promise a more specific assessment of the brain function. To date, most approaches were focused on a "head-to-head" comparison of either electroencephalogram- or standard parameter-based monitoring. In the current study, a multimodal indicator based on a combination of both electro encephalographic and standard anesthesia monitoring parameters is defined for quantification of "anesthesia depth." Two hundred sixty-three adult patients from six European centers undergoing surgery with general anesthesia were assigned to 1 of 10 anesthetic combinations according to standards of the enrolling hospital. The anesthesia multimodal index of consciousness was developed using a data-driven approach, which maps standard monitoring and electroencephalographic parameters into an output indicator that separates different levels of anesthesia from awake to electroencephalographic burst suppression. Obtained results were compared with either a combination of standard monitoring parameters or the electroencephalogram-based bispectral index. The anesthesia multimodal index of consciousness showed prediction probability (P(K)) of 0.96 (95% CI, 0.95 to 0.97) to separate different levels of anesthesia (wakefulness to burst suppression), whereas the bispectral index had significantly lower PK of 0.80 (0.76 to 0.81) at corrected threshold P value of less than 0.05. At the transition between consciousness and unconsciousness, anesthesia multimodal index of consciousness yielded a PK of 0.88 (0.85 to 0.91). A multimodal integration of both standard monitoring and electroencephalographic parameters may more precisely reflect the level of anesthesia compared with monitoring based on one of these aspects alone.

The efficacy of the semi-blind approach of transversus abdominis plane block on postoperative analgesia in patients undergoing inguinal hernia repair: a prospective randomized double-blind study

PurposeIn this prospective, randomized, double-blind study, our aim was to compare the analgesic efficacy of the semi-blind approach of transversus abdominis plane (TAP) block with a placebo block in patients undergoing unilateral inguinal hernia repair.MethodsAfter receiving hospital ethical committee approval and informed patient consents, American Society of Anesthesiologists (ASA) I–III patients aged 18–80 were enrolled in the study. Standard anesthesia monitoring was applied to all patients. After premedication, spinal anesthesia was administered to all patients with 3.5 mL heavy bupivacaine at the L3-L4 subarachnoid space. Patients were randomly allocated into 2 groups. Group I (n = 32) received a placebo block with 20 mL saline, Group II (n = 32) received semi-blind TAP block with 0.25% bupivacaine in 20 mL with a blunt regional anesthesia needle into the neurofascial plane via the lumbar triangle of Petit near the midaxillary line before fascial closure. At the end of the operation, intravenous (IV) dexketoprofen was given to all patients. The verbal analog scale (VAS) was recorded at 2, 4, 6, 12, and 24 hours postoperatively. Paracetamol IV was given to patients if their VAS score > 3. A rescue analgesic of 0.05 mg/kg morphine IV was applied if VA S > 3. Total analgesic consumption and morphine requirement in 24 hours were recorded.ResultsTAP block reduced VAS scores at all postoperative time points (P < 0.001). Postoperative analgesic and morphine requirement in 24 hours was significantly lower in group II (P < 0.01).ConclusionSemi-blind TAP block provided effective analgesia, reducing total 24-hour postoperative analgesic consumption and morphine requirement in patients undergoing elective unilateral inguinal hernia repair.