Effect of desflurane anesthesia on flash visual evoked potential monitoring in patients undergoing spine surgery: study protocol for a randomized controlled trial.

BACKGROUND: Flash visual evoked potentials (FVEPs) are a reliable method for protecting visual function during spine surgery in prone position. However, the popularization and application of FVEPs remain limited due to the unclear influence of various anesthetics on FVEPs. Exploring the effects of anesthetic drugs on FVEP and establishing appropriate anesthesia maintenance methods are particularly important for promoting and applying FVEP. According to the conventional concept, inhaled narcotic drugs significantly affect the success of FVEP monitoring, FVEP extraction, and interpretation. Nonetheless, our previous study demonstrated that sevoflurane-propofol balanced anesthesia was a practicable regimen for FVEPs. Desflurane is widely used in general anesthesia for its rapid recovery properties. As the effect of desflurane on FVEP remains unclear, this trial will investigate the effect of different inhaled concentrations of desflurane anesthesia on amplitude of FVEPs during spine surgery, aiming to identify more feasible anesthesia schemes for the clinical application of FVEP. METHODS/ DESIGN: A total of 70 patients undergoing elective spinal surgery will be enrolled in this prospective, randomized controlled, open-label, patient-assessor-blinded, superiority trial and randomly assigned to the low inhaled concentration of desflurane group (LD group) maintained with desflurane-propofolremifentanil-balanced anesthesia or high inhaled concentration of desflurane group (HD group) maintained with desflurane-remifentanil anesthesia maintenance group at a ratio of 1:1. All patients will be monitored for intraoperative FVEPs, and the baseline will be measured half an hour after induction under total intravenous anesthesia (TIVA). After that, patients will receive 0.5 minimum alveolar concentration (MAC) of desflurane combined with propofol and remifentanil for anesthesia maintenance in the LD group, while 0.7-1.0 MAC of desflurane and remifentanil will be maintained in the HD group. The primary outcome is the N75-P100 amplitude 1 h after the induction of anesthesia. We intend to use the dual measure evaluation, dual data entry, and statistical analysis by double trained assessors to ensure the reliability and accuracy of the results. DISCUSSION: This randomized controlled trial aims to explore the superiority effect of low inhaled concentration of desflurane combined with propofolremifentanil-balanced anesthesia versus high inhaled concentration of desflurane combined with remifentanil anesthesia on amplitude of FVEPs. The study is meant to be published in a peer-reviewed journal and might guide the anesthetic regimen for FVEPs. The conclusion is expected to provide high-quality evidence for the effect of desflurane on FVEPs and aim to explore more feasible anesthesia schemes for the clinical application of FVEPs and visual function protection. TRIAL REGISTRATION: This study was registered on clinicaltrials.gov on July 15, 2022. CLINICALTRIALS: gov Identifier: NCT05465330.

Influence of intravenous fentanyl or dexmedetomidine infusions, combined with lidocaine and ketamine, on cardiovascular response, sevoflurane requirement and postoperative pain in dogs anesthetized for unilateral mastectomy.

OBJECTIVE: To compare the effects of constant rate infusions (CRI) of fentanyl or dexmedetomidine, combined with lidocaine and ketamine, on cardiovascular response during surgery, sevoflurane requirement and postoperative pain in dogs undergoing mastectomy. STUDY DESIGN: Prospective, randomized, blinded, clinical trial. ANIMALS: A total of 29 female dogs with mammary tumors. METHODS: Premedication consisted of intramuscular acepromazine and morphine. General anesthesia was induced with intravenous propofol and maintained with sevoflurane. Dogs were randomized to be administered intravenous DLK [dexmedetomidine 1 µg kg-1 loading dose (LD) and 1 µg kg-1 hour-1; lidocaine 2 mg kg-1 LD and 3 mg kg-1 hour-1; ketamine 1 mg kg-1 LD and 0.6 mg kg-1 hour-1; n = 14] or FLK (fentanyl 5 µg kg-1 LD and 9 µg kg-1 hour-1; same doses of lidocaine and ketamine; n = 15) during anesthesia. Cardiorespiratory variables and end-tidal sevoflurane (Fe'Sevo) were recorded during surgery. The number of dogs administered ephedrine to treat arterial hypotension [mean arterial pressure (MAP) < 60 mmHg] was recorded. Meloxicam was administered to both groups. Postoperative pain and rescue analgesia requirement were assessed for 24 hours using the short form of the Glasgow Composite Measure Pain Scale. Data were compared using a mixed effects model or a Mann-Whitney test. RESULTS: More dogs required ephedrine in FLK than in DLK (67% versus 7%). Heart rate was not significantly different between groups, whereas lower values of MAP (p ≤ 0.01) and Fe'Sevo (p = 0.018) were observed in FLK than in DLK. Rescue analgesia was administered to 2/15 dogs in FLK and 0/14 dogs in DLK. CONCLUSIONS AND CLINICAL RELEVANCE: Based on the cardiovascular response during surgery, intraoperative infusions of FLK and DLK provided adequate antinociception. Infusion of DLK provided greater stability of blood pressure. Both protocols resulted in minimal need for additional analgesia within 24 hours postoperatively.

Worry as Important "Feelers" in Clinical Anesthesia Practice: A Mixed-Methods Study.

PURPOSE: Worry is an intuitive sense that goes beyond logical reasoning and is valuable in situations where patients' conditions are rapidly changing or when objective data may not fully capture the complexity of a patient's situation. Nurse anesthetists' subjective reasons for worry are quite vague as they are valued inconsistently and not accurately expressed. This study aimed to identify factors playing a role in the emergence of worry during anesthesia practice to clarify its concept. DESIGN: Mixed-methods design consisting of quantitative online surveys followed by qualitative focus group interviews including Dutch nurse anesthetists. METHODS: Both quantitative and qualitative thematic analyses were performed, followed by data and methodological triangulation to enhance the validity and credibility of findings and mitigate the presence of bias. FINDINGS: Surveys (N = 102) were analyzed, and 14 nurse anesthetists participated in the focus group interviews. A total of 89% of the survey respondents reported that at least once have had the feeling of worry, of which 92% use worry during clinical anesthesia practice. Worry was mentioned to be a vital element during anesthesia practice that makes it possible to take precautionary actions to change the anesthetic care plan in a changing situation or patient deterioration. CONCLUSIONS: While a clear definition of worry could not be given, it is a valuable element of anesthesia practice as it serves as a catalyst for critical thinking, problem-solving, clinical reasoning, and decision-making. Use of the feeling of worry alongside technological systems to make an informed decision is crucial. Technology has significantly improved the ability of health care providers to detect and respond to patient deterioration promptly, but it is crucial for nurse anesthetists to use their feeling of worry or intuition alongside technological systems and evidence-based practice to ensure quick assessments or judgments based on experience, knowledge, and observations in clinical practice.

The Rise of Remimazolam: A Review of Pharmacology, Clinical Efficacy, and Safety Profiles.

Anesthesiologists often use benzodiazepines (BZDs) due to their remarkable amnestic and anxiolytic capabilities. Because of this, they are perfect for use during the perioperative phase, when patients' anxiety levels are already high. Remimazolam has replaced certain commonly used intravenous (IV) anesthetics due to its excellent safety profile, rapid onset of action, and short half-life. The four classes of BZDs, 2-keto-benzodiazepines, 3-hydroxy-benzodiazepines, triazolobenzodiazepines, and 7-nitro-benzodiazepines based on chemical structure, provide various levels of drowsiness, forgetfulness, and anxiolysis. Based on their elimination half-life, short-acting BZDs typically have a half-life ranging from one to 12 hours, e.g., oxazepam; intermediate-acting BZDs have an average elimination half-life of 12 to 40 hours, e.g., alprazolam; and long-acting BZDs have an average elimination half-life of more than 40 hours, e.g., diazepam. The chloride ion channel is conformationally shifted by the benzodiazepine molecule resulting in central nervous system (CNS) inhibition and hyperpolarization. Each type of benzodiazepine has a favored use. For example, diazepam is used to treat anxiety. Midazolam is used for its anxiolytic and anterograde amnestic effects during the perioperative phase. Anxiety and epilepsy are two conditions that lorazepam effectively treats. There are now phase II and III clinical studies investigating remimazolam. It is not sensitive to alterations in its surroundings and has a brief half-life so that it may be removed rapidly, even after extensive infusion. Being a soft drug means the body easily breaks it down via metabolism, which explains many features. Remimazolam is hydrolyzed into methanol and its carboxylic acid metabolite CNS 7054 by esterase metabolism. Therefore, remimazolam has a shorter onset time and faster recovery than other BZDs. Remimazolam is metabolized independently of any particular organ. Patients with hepatic and renal problems will not see any changes in metabolism or excretion since the drug's ester moiety makes it a substrate for general tissue esterase enzymes. Like its predecessor, midazolam, it has a high potential for addiction. Some side effects that could occur during infusion include headaches and drowsiness. In clinical trials, hypotension, respiratory depression, and bradycardia were noted in participants. BZDs are helpful when used in conjunction with anesthesia. Remimazolam stands out, thanks to its unique pharmacokinetics, pharmacodynamics, safety profile, and potential medical applications. Its desirable properties make it a potential surgical premedication and sedative in the critical care unit. Anesthesiologists and other doctors could have access to more consistent and safer medication. However, additional comprehensive clinical trials are necessary to understand remimazolam's advantages and disadvantages.

Effects of Anesthetic Choice on the Incidence of Transcranial-Motor Potential-Induced Oral Trauma.

Transcranial motor-evoked potentials (TcMEPs) play an integral role in assessing motor tract function in surgical procedures where motor function is at risk. However, transcranial stimulation creates a risk for oral trauma. Several studies have reported on distinct factors that can influence the rate of TcMEP-induced oral trauma, but little is known about how an anesthetic regimen can influence this rate. In this retrospective review, we investigated the incidence of oral injury under total intravenous anesthesia (TIVA) and balanced anesthesia in 66,166 cases from 2019 to 2021. There were 295 oral injuries in our sample, yielding an incidence of 0.45%, which is in line with ranges reported in the literature. A total of 222 of the injured patients were sedated with balanced anesthesia, while the remaining 73 were under TIVA anesthetics. This difference in distribution was statistically significant (p < 0.0002). Our findings suggest TIVA is associated with lower risk of oral trauma when TcMEPs are monitored, thereby improving patient safety.

Balanced volatile sedation with isoflurane in critically ill patients with aneurysmal subarachnoid hemorrhage - a retrospective observational study.

Introduction: In patients with severe aneurysmal subarachnoid hemorrhage (SAH) deep sedation is often used early in the course of the disease in order to control brain edema formation and thus intracranial hypertension. However, some patients do not reach an adequate sedation depth despite high doses of common intravenous sedatives. Balanced sedation protocols incorporating low-dose volatile isoflurane administration might improve insufficient sedation depth in these patients. Methods: We retrospectively analyzed ICU patients with severe aneurysmal SAH who received isoflurane in addition to intravenous anesthetics in order to improve insufficient sedation depth. Routinely recorded data from neuromonitoring, laboratory and hemodynamic parameters were compared before and up to 6 days after initiation of isoflurane. Results: Sedation depth measured using the bispectral index improved in thirty-six SAH patients (-15.16; p = 0.005) who received additional isoflurane for a mean period of 9.73 ± 7.56 days. Initiation of isoflurane sedation caused a decline in mean arterial pressure (-4.67 mmHg; p = 0.014) and cerebral perfusion pressure (-4.21 mmHg; p = 0.013) which had to be balanced by increased doses of vasopressors. Patients required increased minute ventilation in order to adjust for the increase in PaCO2 (+2.90 mmHg; p < 0.001). We did not detect significant increases in mean intracranial pressure. However, isoflurane therapy had to be terminated prematurely in 25% of the patients after a median of 30 h due to episodes of intracranial hypertension or refractory hypercapnia. Discussion: A balanced sedation protocol including isoflurane is feasible for SAH patients experiencing inadequately shallow sedation. However, therapy should be restricted to patients without impaired lung function, hemodynamic instability and impending intracranial hypertension.

Usefulness and Reliability of the Bispectral Index during Balanced Anesthesia for Neurovascular Surgery in New Zealand White Rabbits.

Few data about the electroencephalogram and its calculated indices, such as the bispectral index (BIS), have been reported in rabbits. We aimed to evaluate whether a clinically stable anesthesia was mirrored by consistent and stable BIS values and to investigate the effects of modified cerebral blood supply, due to bilateral carotid clamping and re-opening, on BIS values. We also investigated the effects of fentanyl, as an antinociceptive drug, on the BIS. Sixty-eight rabbits undergoing general anesthesia for surgical creation of carotid bifurcation aneurysms were enrolled. The BIS values were recorded at nine selected time points (TPs) during each procedure and before and after fentanyl administration. The BIS values over time were compared with two-way repeated-measures analysis of variance followed by Tukey test, while the Wilcoxon signed rank test was performed to compare values at clamping and re-opening of the carotids as well as before and after fentanyl administration. The BIS values were significantly lower during anesthesia than at the end of anesthesia and at tracheal extubation; no significant differences were found among other TPs. Adequate depth of anesthesia was mirrored by consistent BIS values among rabbits, and alteration of cerebral blood supply did not modify BIS values, except once. Following fentanyl, BIS values did not change in a clinically relevant way.

Comparison of Postoperative Recovery between Balanced and Total Intravenous Anesthesia in Patients Undergoing Off-Pump Coronary Artery Bypass (OPCAB) Surgery: A Prospective, Single-Blind Randomized Study.

Recovery after anesthesia has a significant impact on a patient's return to daily life. This study was performed to compare the postoperative quality of recovery according to the method of anesthesia administered among patients undergoing OPCAB using the Korean version of the Quality of Recovery-40 (QoR-40K) questionnaire. This single-blind, prospective study (trial number: KCT0004726) was performed using a population of 102 patients undergoing OPCAB under general anesthesia. The patients were randomly assigned to one of two groups using a computer-generated list: a total intravenous anesthesia group (Group T) and a balanced anesthesia group (Group B). The QoR-40K score was measured preoperatively and at 24 and 48 h after extubation. There was no significant difference in the QoR-40K scores between the groups at 24 and 48 h after extubation. In addition, there were no significant differences between groups with respect to any of the five dimensions of QoR-40K at 24 and 48 h after extubation. Finally, there were no differences in the postoperative opioid consumption, time to extubation, or length of hospital stay. In this study, there was no difference in the QoR-40K score at 24 h after extubation between Groups T and B. Therefore, both methods of anesthesia are suitable for use when performing OPCAB.

Influence of Constant Rate Infusions of Fentanyl Alone or in Combination With Lidocaine and Ketamine on the Response to Surgery and Postoperative Pain in Isoflurane Anesthetized Dogs Undergoing Unilateral Mastectomy: A Randomized Clinical Trial.

The aim of this study was to compare the effects of constant rate infusions (CRI) of fentanyl alone or combined with lidocaine and ketamine (FLK), on physiological parameters, isoflurane requirements and the number of postoperative analgesic rescues in dogs undergoing unilateral mastectomy. Twenty-two dogs were premedicated with acepromazine 0.02 mg/kg and morphine 0.5 mg/kg and anesthetized with propofol and isoflurane. Dogs were randomly assigned to 1 of 2 groups: Fentanyl group (fentanyl 5 µg/kg loading dose [LD] and 9 µg/kg/h CRI; n = 11); FLK group (fentanyl [same doses]; lidocaine 2 mg/kg LD and 3 mg/kg/h CRI; ketamine 1.0 mg/kg LD and 0.6 mg/kg/h CRI; = 11). Intraoperative evaluations were performed before the start of surgery and administration of the treatments (T0); three minutes after the LD (T1); during incision and tissue divulsion (T2); during closure of the surgical wound (T3). Meloxicam (0.1 mg/kg) was administered at T3. Blood samples were collected for determination of plasma concentrations of fentanyl, lidocaine and ketamine. Pain scores and the number of postoperative analgesic rescues with morphine (0.5 mg/kg) were evaluated for 24 hours postoperatively using the short form of the Glasgow Composite Measure Pain Scale. Compared to T0, significant decreases in heart rate (from 84 ± 28 to 53 ± 16 bpm in the Fentanyl group and from 93 ± 16 to 63 ± 15 bpm in FLK) and mean arterial pressure (from 61 ± 5 to 49 ± 10 mmHg in Fentanyl and from 59 ± 3 to 38 ± 6 mmHg in FLK) were observed at T1. Arterial hypotension was transient, with normalization of values at T2 and T3. The expired fraction of isoflurane did not differ significantly between the groups. Plasma concentrations of fentanyl, lidocaine and ketamine remained within the therapeutic range. Postoperatively, the number of dogs requiring analgesic rescue was significantly lower in the FLK (0/11, 0%) than in the Fentanyl group (5/11, 45%). In dogs administered morphine and meloxicam as part of the anesthesia protocol, an intraoperative CRI of FLK abolished the requirement for postoperative analgesic rescue for 24 hours in dogs undergoing mastectomy.

Effects of two continuous infusion doses of lidocaine on isoflurane minimum anesthetic concentration in chickens.

OBJECTIVE: To assess the effect of two intravenous (IV) doses of lidocaine on the minimum anesthetic concentration (MAC) of isoflurane in chickens. STUDY DESIGN: Blinded, prospective, randomized, experimental crossover study. ANIMALS: A total of six adult female chickens weighing 1.90 ± 0.15 kg. METHODS: Chickens were anesthetized with isoflurane and mechanically ventilated. Isoflurane MAC values were determined (T0) in duplicate using an electrical noxious stimulus and the bracketing method. After MAC determination, a low dose (LD; 3 mg kg-1 followed by 3 mg kg-1 hour-1) or high dose (HD; 6 mg kg-1 followed by 6 mg kg-1 hour-1) of lidocaine was administered IV. MAC determination was repeated at 1.5 (T1.5) and 3 (T3) hours of lidocaine administration and blood was collected for analysis of plasma lidocaine and monoethylglycinexylidide (MEGX) concentrations. Pulse rate, peripheral hemoglobin oxygen saturation, noninvasive systolic arterial pressure and cloacal temperature were recorded at T0, T1.5 and T3. Treatments were separated by 1 week. Data were analyzed using mixed-effects model for repeated measures. RESULTS: MAC of isoflurane (mean ± standard deviation) at T0 was 1.47 ± 0.18%. MAC at T1.5 and T3 was 1.32 ± 0.27% and 1.26 ± 0.09% (treatment LD); and 1.28 ± 0.06% and 1.30 ± 0.06% (treatment HD). There were no significant differences between treatments or times. Maximum plasma lidocaine concentrations at T3 were 496 ± 98 and 1200 ± 286 ng mL-1 for treatments LD and HD, respectively, and were not significantly different from T1.5. With treatment HD, plasma concentration of MEGX was significantly higher at T3 than at T1.5. Physiological variables were not significantly different among times with either treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of lidocaine did not significantly change isoflurane MAC in chickens. Within treatments, plasma lidocaine concentrations were not significantly different at 1.5 and 3 hours.

Anesthesia-related postoperative oncological surgical outcomes: a comparison of total intravenous anesthesia and volatile anesthesia. A meta-analysis.

Introduction: In patients undergoing cancer surgery, it is ambiguous whether propofol-based total intravenous anesthesia (TIVA) elicits a significantly higher overall survival rate than volatile anesthetics (VA). Consequently, evaluating the impact of TIVA and VA on long-term oncological outcomes is crucial. Aim: This study compared TIVA versus VA for cancer surgery patients and investigated the potential correlation between anesthetics and their long-term surgical outcomes. Material and methods: A comprehensive search of Medline, EMBASE, Scopus, and Cochrane Library identified English-language peer-reviewed journal papers. The statistical measurements of hazard ratio (HR) and 95% CI were calculated. We assessed heterogeneity using Cochrane Q and I2 statistics and the appropriate p-value. The analysis used RevMan 5.3. Results: The meta-analysis included 10 studies with 14036 cancer patients, 6264 of whom received TIVA and 7777 VA. In this study, we examined the long-term oncological outcomes of cancer surgery patients with TIVA and VA. Our data show that the TIVA group had a considerably higher overall survival rate (HR = 0.49, 95% CI: 0.30-0.80) and recurrence-free survival rate (HR = 0.56, 95% CI: 0.32-0.97). Each outcome was statistically significant (p < 0.05). Conclusions: The present study concludes that TIVA is a more effective anesthetic agent than VA in obtaining better long-term oncological outcomes in cancer patients after surgery as it provides a higher overall survival rate, a higher recurrence-free survival rate and fewer post-operative pathological findings in patients who have undergone surgery for cancer as compared to VA.

Response surface model comparison and combinations for remifentanil and propofol in describing response to esophageal instrumentation and adverse respiratory events.

BACKGROUND: The primary aim of this essay was to explore the best fitting model in remifentanil-propofol combined administrations during esophageal instrumentation (EI) from five distinct response surface models. The secondary aim was to combine the models to give appropriate effect-site drug concentrations (Ces) range with maximal comfort and safety. METHODS: The Greco, reduced Greco, Minto, Scaled C50 Hierarchy and Fixed C50 Hierarchy models were constructed to fit four drug effects: loss of response to esophageal instrumentation (LREI), loss of response to esophageal instrumentation revised (LREIR), intolerable ventilatory depression (IVD) and respiratory compromise (RC). Models were tested by chi-square statistical test and evaluated with Akaike Information Criterion (AIC). Model prediction performance were measured by successful prediction rate (SPR) and three prediction errors. RESULTS: The reduced Greco model was the best fitting model for LREI and RC, and the Minto model was the best fitting model for LREIR and IVD. The SPRs of reduced Greco model for LREI and RC were 81.76% and 79.81%. The SPRs of Minto model for LREIR and IVD were 80.32% and 80.12%. Overlay of the reduced Greco model for LREI and Minto model for IVD offered visual aid for guidance in drug administration. CONCLUSION: Using proper response surface model to fit different drug effects will describe the interactions between anesthetic drugs better. Combining response surface models to select the more reliable effect-site drug concentrations range can be used to guide clinical drug administration with greater safety and provide an improvement of anesthesia precision.

Comparison of direct costs associated with the use of balanced general anesthesia and total intravenous anesthesia (TIVA) techniques / Comparación de los costos directos asociados al uso de técnicas de anestesia general balanceada y anestesia total intravenosa (TIVA)

Abstract Introduction: Healthcare costs are increasing against the backdrop of scarce resources. Surgical procedures are an important part of healthcare spending, and the cost of anesthetic techniques is relevant as part of the total cost of care and it is a potential target for expenditure optimization. Although important economic differences have been reported internationally for general anesthesia options, there are no publications in Colombia that compare current costs and allow for informed and financially responsible decision-making. Objective: To quantify and compare direct costs associated with the various general anesthesia options most frequently used at the present time. Methods: Cost minimization analysis based on a theoretical model of balanced general anesthesia using isoflurane, sevoflurane, desflurane in combination with remifentanil, and TIVA (propofol and remifentanil). Initial results were obtained using a deterministic simulation method and a sensitivity analysis was performed using a Monte Carlo simulation. Results: The average total cost per case for the different anesthetic techniques was COP 126381 for sevoflurane, COP 97706 for isoflurane, COP 288605 for desflurane and COP 222 960 for TIVA. Conclusions: Balanced general anesthesia with desflurane is the most costly alternative, 1.2 times more expensive than TIVA, and 2 and 3 times more costly than balanced anesthesia with sevoflurane and isoflurane, respectively. TIVA ranks second with a cost 1.8 times higher than balanced anesthesia with sevoflurane and 2.5 times higher than balanced anesthesia with isoflurane.

Resumen Introducción: Los costos de la atención en salud son crecientes y se enfrentan a un escenario de recursos escasos. La realización de procedimientos quirúrgicos hace parte importante de la atención y del gasto en salud, el costo de las técnicas anestésicas utilizadas es relevante en el costo total de la atención y es un objetivo potencial para la optimización del gasto. Aunque a escala internacional se han reportado diferencias económicas importantes entre las alternativas para anestesia general, en Colombia no se cuenta con publicaciones que comparen los costos actuales y permitan una toma de decisiones informada y responsable económicamente. Objetivo: Cuantificar y comparar los costos directos para Colombia de las diferentes alternativas para anestesia general usadas con más frecuencia en la actualidad. Métodos: Análisis de minimización de costos basado en un modelo teórico de anestesia general balanceada con isoflurano, sevoflurano, desflurano en combinación con remifentanilo y TIVA (propofol y remifentanilo). Se obtuvieron resultados iniciales utilizando una simulación con un método determinista y se realizó un análisis de sensibilidad con una simulación de Montecarlo. Resultados: El costo total promedio por caso para las diferentes técnicas anestésicas fue de COP 126.381 para sevoflurano, COP 97.706 para isoflurano, COP 288.605 para desflurano y COP 222.960 para TIVA. Conclusiones: La anestesia general balanceada con desflurano es la alternativa de mayor costo, es 1,2 veces más costosa que la TIVA, y 2 y 3 veces más que la balanceada con sevoflurano e isoflurano, respectivamente. La TIVA ocupa el segundo lugar con un costo 1,8 veces superior a la balanceada con sevoflurano y 2,5 veces a la balanceada con isoflurano.

Less Fluctuation in Hemodynamics of the Wide-Awake Local Anesthesia No Tourniquet Technique Than General Anesthesia in Distal Radius Plating Surgery: A Prospective Case-Control Study.

This prospective case-control study aimed to compare the intraoperative hemodynamic changes between the wide-awake local anesthesia no tourniquet (WALANT) technique and general anesthesia (GA) in patients undergoing distal radius plating surgery. Forty adults with distal radius fractures underwent plating surgery via the WALANT technique (20 patients) or GA (20 patients). Mean arterial pressure (MAP) and heart rate were recorded. Intraoperative pain intensity was measured using the visual analog scale (VAS) for pain in the WALANT group. The measures of hemodynamics and VAS were recorded at seven-time points perioperatively. The VAS score decreased significantly compared with the preoperative status in the WALANT group for most of the intraoperative period except during injections of local anesthetics and fracture reduction. The intraoperative MAP in the WALANT group showed no significant change during the perioperative period. In addition, the WALANT group showed fewer perioperative MAP fluctuations than the GA group (p < 0.05). The reduction and plating quality were similar between the two groups. WALANT provided a feasible technique with less fluctuation in hemodynamic status. With gentle manipulation of the fracture reduction, distal radius plating surgery using the WALANT technique is a well-tolerated surgical procedure and shows similar reduction and plating quality to GA.

Opioid-free versus opioid-based anesthesia in pancreatic surgery.

BACKGROUND: Opioid-free anesthesia (OFA) is associated with significantly reduced cumulative postoperative morphine consumption in comparison with opioid-based anesthesia (OBA). Whether OFA is feasible and may improve outcomes in pancreatic surgery remains unclear. METHODS: Perioperative data from 77 consecutive patients who underwent pancreatic resection were included and retrospectively reviewed. Patients received either an OBA with intraoperative remifentanil (n = 42) or an OFA (n = 35). OFA included a combination of continuous infusions of dexmedetomidine, lidocaine, and esketamine. In OBA, patients also received a single bolus of intrathecal morphine. All patients received intraoperative propofol, sevoflurane, dexamethasone, diclofenac, neuromuscular blockade. Postoperative pain management was achieved by continuous wound infiltration and patient-controlled morphine. The primary outcome was postoperative pain (Numerical Rating Scale, NRS). Opioid consumption within 48 h after extubation, length of stay, adverse events within 90 days, and 30-day mortality were included as secondary outcomes. Episodes of bradycardia and hypotension requiring rescue medication were considered as safety outcomes. RESULTS: Compared to OBA, NRS (3 [2-4] vs 0 [0-2], P < 0.001) and opioid consumption (36 [24-52] vs 10 [2-24], P = 0.005) were both less in the OFA group. Length of stay was shorter by 4 days with OFA (14 [7-46] vs 10 [6-16], P < 0.001). OFA (P = 0.03), with postoperative pancreatic fistula (P = 0.0002) and delayed gastric emptying (P < 0.0001) were identified as only independent factors for length of stay. The comprehensive complication index (CCI) was the lowest with OFA (24.9 ± 25.5 vs 14.1 ± 23.4, P = 0.03). There were no differences in demographics, operative time, blood loss, bradycardia, vasopressors administration or time to extubation among groups. CONCLUSIONS: In this series, OFA during pancreatic resection is feasible and independently associated with a better outcome, in particular pain outcomes. The lower rate of postoperative complications may justify future randomized trials to test the hypothesis that OFA may improve outcomes and shorten length of stay.

Spontaneous breathing for managing analgesia during balanced anesthesia with remifentanil and desflurane: a prospective, single center randomized controlled trial.

The main goal of anesthesiology is to achieve the best level of analgesia and a fast recovery of consciousness following anesthesia. The preservation of spontaneous breathing during general anesthesia with anesthetic gases is practiced by many anesthetists. However, very few studies have dealt with these positive properties of volatile anesthetics such as sevoflurane or desflurane. Remifentanil is a very short half-life opiate that combines sufficient intra-operative analgesia with a fast post-operative recovery time. We tested the hypothesis that spontaneous breathing can reduce overdosing with remifentanil during desflurane anesthesia. In this prospective, single center, multiple anesthetist study, 30 patients were randomized into two groups (volume-controlled ventilation mode and spontaneous breathing). The spontaneous breathing group showed a significantly lower post-operative pain level than the volume-controlled ventilation mode group. Furthermore, less remifentanil as well as less piritramide was needed in the spontaneous breathing group compared with volume-controlled ventilation mode. It was possible to achieve spontaneous breathing in all patients with 0.6 minimum alveolar concentration desflurane, in order to control the remifentanil rate and prevent an overdose. All spontaneous breathing patients had low intra- and post-operative pain levels and the need for analgesics was equal to or lower than that in the volume-controlled ventilation mode group. By reducing the intra-operative amount of opiates, both the post-operative pain and the amount of post-operative analgesia required can be reduced. A balanced anesthesia with spontaneous intra-operative breathing is needed to determine the required amount of opiates. This study was approved by the Ethic Committee of the Ruhr-University of Bochum (approval No. 2435) in September, 2004.

A novel balanced anesthesia shortens time to emergence in patients undergoing modified radical mastectomy: a randomized prospective trial.

BACKGROUND: In balanced anesthesia, protocol during the last 30 min is very important to guarantee rapid emergence and smooth extubation. In clinical practice, sevoflurane and propofol are often used in combination to achieve a better anesthetic effect and less adverse reaction. Approximately 30 min before surgical completion, sevoflurane inhalation is often discontinued and propofol is adjusted to keep sufficient depth of anesthesia. However, propofol-based anesthesia may delay time to emergence due to its unpredictable interindividual variability. In contrast, sevoflurane can be rapidly excreted unchanged from the respiratory tract, and more importantly, with minimal variability. This study aimed to investigate the effect of a novel balanced anesthesia protocol, that is propofol-based intravenous induction, propofol-sevoflurane combined maintenance, and total sevoflurane inhalation during the last 30 min of the surgery, on the time to emergence/extubation. METHODS: In our study, a total of 100 female patients undergoing modified radical mastectomy were enrolled. All patients received propofol-based intravenous anesthesia for induction followed by propofolsevoflurane combined maintenance. Approximately 30 min before the end of surgery, sevoflurane was continually inhaled without propofol infusion in group Sev (n=50), while propofol was only infused in group Pro (n=50). The primary outcome was the time to emergence/extubation. The second outcomes included time to respiratory recovery, and duration of post-anesthesia care unit (PACU) stay. The hemodynamic parameters and incidences of postoperative adverse events such as hypoxemia, nausea, vomiting, dizziness, and emergence agitation (EA) were also assessed. RESULTS: The time to emergence/extubation in group Sev was shorter than that in group Pro (12.74±4.31 vs. 17.74±4.27 min, P<0.0001). Similarly, time to respiratory recovery, and duration of PACU stay were significantly shortened in group Sev (all P<0.0001). Most of the patients in group Sev were extubated under a totally waking state of consciousness. The hemodynamic parameters and incidences of postoperative hypoxemia, nausea, vomiting, dizziness, and EA during the PACU stay were similar between the two groups. CONCLUSIONS: In patients undergoing modified radical mastectomy, this novel balanced anesthesia method could shorten the time to emergence/extubation and better waking state without increasing the incidence of adverse events.

Change of inspired oxygen concentration in low flow anesthesia.

BACKGROUND: There are several advantages of low flow anesthesia including safety, economics, and eco-friendliness. However, oxygen concentration of fresh gas flow and inspired gas are large different in low flow anesthesia. This is a hurdle to access to low flow anesthesia. In this study, we aimed to investigate the change in inhaled oxygen concentration in low flow anesthesia using oxygen and medical air. METHODS: A total of 60 patients scheduled for elective surgery with an American Society of Anesthesiologist physical status I or II were enrolled and randomly allocated into two groups. Group H: Fresh gas flow rate (FGF) 4 L/min (FiO2 0.5). Group L: FGF 1 L/min (FiO2 0.5). FGF was applied 4 L/min in initial phase (10 min) after intubation. After initial phase FGF was adjusted according to groups. FGF continued at the end of surgery. Oxygen and inhalation anesthetic gas concentration were recorded for 180 min at 15 min interval. RESULTS: The inspired oxygen concentration decreased by 5.5% during the first 15 min in the group L. Inspired oxygen decreased by 1.5% during next 15 min. Inspired oxygen decreased by 1.4% for 30 to 60 min. The inspired oxygen of group L is 35.4 ± 4.0% in 180 min. The group H had little difference in inspired oxygen concentration over time and decreased by 1.8% for 180 min. CONCLUSIONS: The inspired oxygen concentration is maintained at 30% or more for 180 min in patients under 90 kg. Despite some technical difficulties, low flow anesthesia may be considered.

A novel application of Transnasal Humidified Rapid Insufflation Ventilatory Exchange via the oral route in morbidly obese patient during monitored anesthesia care - A case report.

BACKGROUND: Transnasal Humidified Rapid Insufflation Ventilatory Exchange (THRIVE) is used to improve oxygenation, with the added benefit of a smaller increase in CO2 if self-respiration is maintained with THRIVE. Despite these advantages, the use of THRIVE through a nasal cannula is limited in situations such as epistaxis or a basal skull fracture. CASE: We successful used THRIVE, through the oral route under general anesthesia with spontaneous breathing in a morbidly obese patient (weight, 148 kg; height, 183 cm; body mass index, 44.2 kg/m2) who received transnasal steroid injections due to subglottic stenosis. CONCLUSIONS: THRIVE through the oral route may be an effective novel option, although further studies are needed.

Ventajas de la anestesia intravenosa libre de opioides en cirugía ambulatoria oncológica de mama / Advantages of opioid-free intravenous anesthesia over anesthesia in ambulatory breast cancer surgery

RESUMEN Introducción: la anestesia general libre de opioides surge ante la necesidad de evasión del uso de opioides en el transoperatorio y sus efectos indeseados en el posoperatorio. Objetivo: evaluar el comportamiento hemodinámico y la recuperación anestésica en pacientes intervenidas mediante cirugía ambulatoria por cáncer de mama, en las cuales se administró anestesia general total intravenosa libre de opioides o general balanceada. Métodos: se realizó un estudio cuasiexperimental, prospectivo en pacientes a las que se aplicó anestesia general balanceada (n=34) y total intravenosa libre de opioides (n=34) intervenidas quirúrgicamente por cáncer de mama, en el Hospital General Docente "Abel Santamaría Cuadrado", durante el 2018. Resultados: el grupo de anestesia general balanceada mostró mayor variación intraoperatoria de los parámetros evaluados, con diferencias significativas (p=0,019). El tiempo medio de despertar fue menor en el grupo de anestesia total intravenosa (2,10 ± 0,907 min vs 5,35 ± 1,250 min; p<0,01), al igual que el dolor, con diferencia significativa (p<0,05) y el tiempo de recuperación, donde una hora después de la intervención, el 85 % cumplía los criterios de alta anestésica. El retraso en el alta de la unidad de recuperación ocurrió principalmente por el bajo nivel de actividad motora, con mayor incidencia en el grupo de anestesia general balanceada (71 % vs 26 %; p=0,00). Conclusiones: la anestesia total intravenosa libre de opioides fue superior al método general balanceado, pues mostró mayor estabilidad hemodinámica y analgesia, menor incidencia de complicaciones posoperatorias y menor tiempo de estancia en sala de recuperación posanestésica.

ABSTRACT Introduction: opioid-free general anesthesia arises from the need to avoid the use of opioids in the transoperative period and the undesirable effects in the postoperative period. Objective: to assess the hemodynamic behavior and anesthetic recovery in patients who underwent ambulatory surgery for breast cancer and those who were given either opioid-free intravenous general or balanced general anesthesia. Methods: a quasi-experimental, prospective study was carried out on patients who received balanced general anesthesia (n=34) and total opioid-free intravenous anesthesia (n=34), who underwent breast cancer surgery at Abel Santamaria Cuadrado General Teaching Hospital during 2018. Results: the group of balanced general anesthesia showed greater intraoperative variation of the parameters assessed, with significant differences (p=0.019). The mean time of awakening was lower in the intravenous total anesthesia group (2.10 ± 0,907 min vs. 5,35 ± 1,250 min; p<0.01), as was pain, with significant difference (p<0.05) and the recovery time, where one hour after the surgery, 85 % met the criteria for anesthesia discharge. The delay in discharge from the recovery unit occurred mainly because of the low level of motor activity, with a higher incidence in the group of balanced general anesthesia (71% vs. 26 %; p=0.00). Conclusions: intravenous opioid-free total anesthesia was higher to the balanced general approach because it showed greater hemodynamic and analgesic stability, lower incidence of postoperative complications, and shorter time spent in the post-anesthesia recovery room.