Comparative evaluation between two methods of induced hypotension with infusion of Remifentanil and Labetalol during sinus endoscopy

Remimazolam to prevent hemodynamic instability during catheter ablation under general anesthesia: a randomized controlled trial

PURPOSE

Maintaining hemodynamic stability during cardiac ablation under general anesthesia is challenging. Remimazolam, a novel ultrashort-acting benzodiazepine, is characterized by maintaining comparatively stable blood pressure and does not influence the cardiac conduction system, which renders it a reasonable choice for general anesthesia for cardiac ablation. We aimed to evaluate whether remimazolam is associated with a decreased incidence of intraoperative hypotension compared with desflurane.

METHODS

In this single-centre, parallel-group, prospective, single-blind, randomized clinical trial, we randomized patients (1:1) into a remimazolam group (remimazolam-based total intravenous anesthesia) or desflurane group (propofol-induced and desflurane-maintained inhalational anesthesia) during cardiac ablation procedures for arrhythmia. The primary outcome was the incidence of intraoperative hypotensive events, defined as mean arterial pressure of < 60 mm Hg at any period.

RESULTS

Overall, we enrolled 96 patients between 2 August 2022 and 19 May 2023 (47 and 49 patients in the remimazolam and desflurane groups, respectively). The remimazolam group showed a significantly lower incidence of hypotensive events (14/47, 30%) than the desflurane group (29/49, 59%; relative risk [RR], 0.5; 95% confidence interval [CI], 0.31 to 0.83; P = 0.004). Remimazolam was associated with a lower requirement for bolus or continuous vasopressor infusion than desflurane was (23/47, 49% vs 43/49, 88%; RR, 0.56; 95% CI, 0.41 to 0.76; P < 0.001). No between-group differences existed in the incidence of perioperative complications such as nausea, vomiting, oxygen desaturation, delayed emergence, or pain.

CONCLUSIONS

Remimazolam was a viable option for general anesthesia for cardiac ablation. Remimazolam-based total intravenous anesthesia was associated with significantly fewer hypotensive events and vasopressor requirements than desflurane-based inhalational anesthesia was, without significantly more complications.

STUDY REGISTRATION

ClinicalTrials.gov (NCT05486377); first submitted 1 August 2022.

Does preoperative administration of hypotensive agents affect the quality of the surgical field during endoscopic sinus surgery? A triple-blind randomized controlled trial

PURPOSE

Endoscopic sinus surgery (ESS) is a surgical procedure widely used in the treatment of various sinonasal conditions. Excessive bleeding during ESS leads to potentially major complications. The primary aim of this trial was to explore any different effects of bisoprolol and nifedipine on the intraoperative surgical field. In addition, the correlations regarding surgical field state, total blood loss (TBL), mean arterial pressure (MAP), and heart rate (HR) were also examined.

METHODS

A prospective, triple-blinded, randomized, placebo-controlled trial was conducted, including 72 patients between 18 and 65 years of age who underwent ESS. As an indicator of the worst state of the intraoperative surgical field, the Boezaart scale score was used, as evaluated by two surgeons. Appropriate statistical analysis was conducted to explore score comparisons across groups and correlations between vital signs, bleeding, and the operative field state.

RESULTS

No statistically significant difference was found among different intervention groups regarding the worst state of the surgical field (p = 0.367 > 0.05). The Boezaart scale score was positively correlated with TBL (rxy = 0.619, p = 0.000 < 0.001) and MAP (rxy = 0.259, p = 0.028 < 0.05). Furthermore, MAP was positively correlated with HR (rs = 0.254, p = 0.32 < 0.05).

CONCLUSION

Our study demonstrates that preoperative administration of bisoprolol and nifedipine does not affect the worst state of the operative field. However, vital signs seem to either directly or indirectly affect bleeding and operative field state, and agents affecting them are worth exploring further.

Effects of remimazolam on hemodynamic changes during cardiac ablation for atrial fibrillation under general anesthesia: a propensity-score-matched retrospective cohort study

PURPOSE

Abrupt hemodynamic changes or life-threatening arrhythmias are frequently observed in individuals receiving anesthesia for cardiac arrhythmia ablation. Remimazolam is a novel ultra-short-acting benzodiazepine that has been associated with better hemodynamic stability than conventional anesthetic agents do. This study aimed to investigate whether remimazolam reduces vasoactive agent use compared with desflurane in individuals undergoing ablation for atrial fibrillation under general anesthesia.

METHODS

In a retrospective cohort study, we reviewed electronic medical records of adult patients who underwent ablation for atrial fibrillation under general anesthesia between July 2021 and July 2022. We divided patients into remimazolam and desflurane groups according to the principal agent used for anesthesia. The primary endpoint was the overall incidence of vasoactive agent use. We compared the groups using propensity-score matching (PSM) analysis.

RESULTS

A total of 177 patients were included-78 in the remimazolam group and 99 in the desflurane group. After PSM, 78 final patients were included in each group. The overall incidence of vasoactive agent use was significantly lower in the remimazolam group than in the desflurane group (41% vs 74% before PSM; 41% vs 73% after PSM; both, P < 0.001). The incidence rate, duration, and maximum dose of continuous vasopressor infusion were also significantly lower in the remimazolam group (P < 0.001). Use of remimazolam was not associated with increased complications after the ablation procedures.

CONCLUSIONS

General anesthesia using remimazolam vs desflurane was associated with significantly reduced vasoactive agent requirement and better hemodynamic stability without increased postoperative complications in patients undergoing ablation for atrial fibrillation.

Short-acting versus long-acting opioids for pediatric postoperative pain management

INTRODUCTION

Opioids are potent analgesics commonly used to manage children's moderate to severe perioperative pain in children. A wide range of short and long-acting opioids are used to treat surgical pain and will be reviewed in this article.

AREAS COVERED

Both short- and long-acting opioids contain unique therapeutic benefits and adverse effects; however, due to the side effect profile and safety concerns, lack of familiarity, and evidence with long-acting opioids to treat surgical pain, shorter-acting opioids have traditionally been used in children. Almost all opioids work by binding to the mu receptor. Methadone, a long-acting opioid, is an exception because it also has beneficial N-methyl-D-aspartate antagonist properties. Clinically methadone's properties could translate to improved analgesic outcomes, reduced risk of adverse events, less risk for acute hyperalgesia, tolerance and abuse potential, faster recovery, and reduced risk for chronic persistent surgical pain. This review article summarizes and compares the evidence of commonly used short and long-acting opioids for perioperative pain control in the pediatric population.

EXPERT OPINION

Individualized methadone therapy using pharmacogenomics has the potential to transform opioid use in pain management by improving patient safety and analgesic outcomes, thereby addressing the gaps in current standardized ERAS protocols.

Pre-procedural Preparation and Sedation for Gastrointestinal Endoscopy in Patients with Advanced Liver Disease

Gastrointestinal endoscopy in patients with advanced liver disease poses various challenges, a major one being procedural sedation and its associated considerations. While sedation during endoscopy can improve patient comfort, decrease anxiety, and facilitate procedural completion, in patients with advanced liver disease, it is also associated with substantial and unique risks due to alterations in drug metabolism and other factors. As such, the choice of sedative agent(s) and related logistics may require careful inter-disciplinary planning and individualized considerations. Furthermore, a large proportion of agents require dose reductions and particular monitoring of the vital signs, level of consciousness, and other indices. In the present review, we provide a contemporary overview of procedural sedation considerations, commonly used intravenous sedatives, and second-line as well as novel sedatives for gastrointestinal endoscopy in patients with advanced liver disease.

Comparison of the Effect of Two Different Doses of Labetalol to Induce Controlled Hypotension on Hemodynamic Changes During Spinal Fusion Surgery

Background: Spinal fusion surgery is often associated with heavy bleeding. Labetalol is one of the most effective drugs used to control bleeding in surgery. Objectives: Here, we measured the effect of two therapeutic doses of labetalol on the amount of bleeding. Methods: This is a randomized clinical trial that was performed in 2020-2021 in Al-Zahra hospital in Isfahan, Iran, on patients that were candidates for posterior spinal fusion surgery under general anesthesia. A total number of 64 patients were entered and randomized into two groups, one receiving labetalol at the dose of 2 mg/min and another group at 4 mg/min during surgery. The amount of bleeding in patients, heart rate, blood pressure, blood oxygen saturation, hypotension or bradycardia, and the mean length of stay in the recovery room were measured and compared between the groups. Results: Extubation time (14 ± 4) and recovery time (76 ± 17) were significantly lower in patients that received labetalol (2 mg/min) compared to another group (21 ± 7 for intubation time and 116 ± 32 for recovery time (P < 0.001 for both items). Patients that received labetalol (4 mg/min) had significantly lower amounts of hemorrhage compared to other group (P = 0.001), and the surgeon's satisfaction was significantly higher in the second group (P = 0.001). The frequency of hypotension and bradycardia during the surgery were significantly higher among patients that received labetalol at the dose of 4 mg/min (P = 0.002 and P = 0.001, respectively). The patients in the group labetalol at 4 mg/min had also significantly lower systolic and diastolic blood pressure and lower mean arterial pressure (MAP) compared to the other group (P < 0.05). Conclusions: Administration of labetalol at the dose of 4 mg/min had significantly desirable effects on hemodynamics that resulted in reduced bleeding volume and blood pressures compared to labetalol at the dose of 2 mg/min.

The Efficacy of Hypotensive Agents on Intraoperative Bleeding and Recovery Following General Anesthesia for Nasal Surgery: A Network Meta-Analysis

OBJECTIVES

A systematic review of the literature was conducted to evaluate hypotensive agents in terms of their adverse effects and associations with perioperative morbidity in patients undergoing nasal surgery.

METHODS

Two authors independently searched databases (Medline, Scopus, and Cochrane databases) up to February 2020 for randomized controlled trials comparing the perioperative administration of a hypotensive agent with a placebo or other agent. The outcomes of interest for this analysis were intraoperative morbidity, operative time, intraoperative bleeding, hypotension, postoperative nausea/vomiting, and postoperative pain. Both a standard pairwise meta-analysis and network meta-analysis were conducted.

RESULTS

Our analysis was based on 37 trials. Treatment networks consisting of six interventions (placebo, clonidine, dexmedetomidine, beta-blockers, opioids, and nitroglycerine) were defined for the network meta-analysis. Dexmedetomidine resulted in the greatest differences in intraoperative bleeding (-0.971; 95% confidence interval [CI], -1.161 to -0.781), intraoperative fentanyl administration (-3.683; 95% CI, -4.848 to -2.518), and postoperative pain (-2.065; 95% CI, -3.170 to -0.960) compared with placebo. The greatest difference in operative time compared with placebo was achieved with clonidine (-0.699; 95% CI, -0.977 to -0.421). All other agents also had beneficial effects on the measured outcomes. Dexmedetomidine was less likely than other agents to cause adverse effects.

CONCLUSION

This study demonstrated the superiority of the systemic use of dexmedetomidine as a perioperative hypotensive agent compared with the other five tested agents. However, the other agents were also superior to placebo in improving operative time, intraoperative bleeding, and postoperative pain.

Does intravenous tranexamic acid reduce bleeding during mastoidectomy?

Mastoidectomy is one of the important head and neck surgeries which is mostly performed due to complications of otitis media. This procedure is performed under microscopic surgery and as a result, a clean visual field is required for surgeons. Bleeding is one of the important issues during microscopic surgeries which reduces visualization. In this clinical trial, we aimed to examine effects of tranexamic acid in reducing bleeding during mastoidectomy. Here we investigated 69 patients who were candidates of mastoidectomy. Patients were randomized into two groups. In group 1, patients received tranexamic acid (10 mg/kg) at the beginning of surgeries along with other anesthetic drugs. In group 2, patients received normal saline as placebo with the same volume. Data regarding to bleeding, duration of surgeries, heart rate and blood pressure of patients were collected and analyzed. We indicated that administration of tranexamic acid is associated with significant reduced bleeding and also reduced blood pressure during surgeries (P<0.001). Taken together, we suggest that otolaryngologists should administer tranexamic acid during microscopic surgeries in order to reduce bleeding and provide a better visual field.

Anesthetic Management of a Pediatric Patient With Bardet-Biedl Syndrome: A Case Report

Bardet-Biedl syndrome is a rare autosomal recessive genetic disorder that affects many organ systems. In cases of Bardet-Biedl syndrome, since the risk of developing inspiratory, cardiovascular, and metabolic problems is high, endotracheal intubation and anesthesia management are difficult. In this report, we present our experience in the management of anesthesia during endoscopic sinus surgery that was performed for the first time on a 6-year-old pediatric patient diagnosed with Bardet-Biedl syndrome.

Effects of small-dose remifentanil combined with index of consciousness monitoring on gastroscopic polypectomy: a prospective, randomized, single-blinded trial

BACKGROUND

With the development of painless diagnosis and treatment, remifentanil, a synthetic opioid agonist, is increasingly used in gastroscopy for its rapid, short-term, and potent analgesic effect. However, the dosage of remifentanil used in endoscopy is unclear. Index of consciousness (IOC) is a new anesthesia depth-monitoring indicator that can be divided into index of consciousness 1 (IOC₁) and index of consciousness 2 (IOC₂); IOC₁ is used for estimating a patient's sedation state, whereas IOC₂ reflects analgesic depth. We hypothesized that combining with IOC₁ and IOC₂ monitoring may be helpful to identify an optimal remifentanil dosage in gastroscopic polypectomy.

METHODS

One hundred twenty patients scheduled for gastroscopic polypectomy were enrolled and were randomly assigned to remifentanil 2 ng/mL (group R2), 4 ng/mL (group R4), or 6 ng/mL (group R6), and 40 cases were in each group. During the anesthesia period, remifentanil was kept at the initial given concentration but propofol was adjusted according to IOC₁. The primary outcomes were the dosage of propofol and remifentanil. The secondary outcomes were the variety of IOC₁ and IOC₂, patients' awakening time, and peri-operative adverse reactions such as hypotension, hypertension, bradycardia, tachycardia, body movements, hypoxemia, therapy interruption, nausea, vomiting, aspiration, and intra-operative awareness.

RESULTS

With the increasing dosage of remifentanil, the propofol dosage and patients' awakening time decreased significantly, the morbidity of hypertension and body movements also declined, but the incidence of hypotension, bradycardia, and hypoxemia rose. In group R2, the value of IOC₂ remained above 50 during the treatment. However, IOC₂ dropped to below 30 at the beginning of the gastroscopy in group R6, and there was statistical difference in hypoxemia between groups R2 and R6 (P <0.05).

CONCLUSIONS

With the help of IOC monitoring, we found that a target concentration of remifentanil 4 ng/mL is comparatively ideal in patients under gastroscopic polypectomy.

TRIAL REGISTRATION

Chinese Clinical Trial Register: ChiCTR-OOD-16009489 , on October 19, 2016.

Effects of remifentanil with or without midazolam pretreatment on the 95% effective dose of propofol for loss of consciousness during induction: A randomized, clinical trial

BACKGROUND

Propofol is a rapid, efficient hypnotic agent with antiemetic effects. However, a high dosage is related to hemodynamic abnormalities such as hypotension and bradycardia. Pretreatment with remifentanil can decrease injection pain and stabilize hemodynamics during the induction period. Remifentanil or midazolam in combination with propofol can provide synergistic or additive effects during anesthesia induction. However, the hypnotic doses of propofol required in patients who receive pretreatment with remifentanil or midazolam remain unclear.

METHODS

Patients aged 20 to 50 years who were scheduled to undergo surgery under general anesthesia were enrolled in this study. The patients were randomized into 3 groups using a computer-generated randomization table. Patients in Group P (Propofol) received only propofol for loss of consciousness, those in Group PR (Propofol-Remifentanil) received remifentanil prior to propofol, and those in Group PMR (Propofol-Midazolam-Remifentanil) received remifentanil and midazolam prior to propofol. After propofol administration, loss of both the eyelash reflex and verbal response represented success. The 95% effective dose of propofol for loss of consciousness in each group, which was the primary outcome, was determined using a modified biased coin up-and-down method.

RESULTS

A total of 124 patients were initially enrolled. Of these, 4 were excluded, and the remaining 120 patients were randomized to each (n = 40) of the 3 groups. The 95% effective dose of propofol for loss of consciousness was 1.74 , 1.38, and 0.92 mg/kg in Groups P, PR, and PMR, respectively. Blood pressure decreased at 2 minutes after propofol administration in all the groups. However, compared with Group P, Groups PR and PMR exhibited a significant decrease in blood pressure.

CONCLUSIONS

The effective dose of propofol for loss of consciousness could be decreased by 21% and 47% when remifentanil pretreatment was used without and with midazolam, respectively. However, the decrease in blood pressure was greater with pretreatment than sole propofol use. These findings suggest that the combination of remifentanil with or without midazolam may have no benefit on hemodynamic stability during induction using propofol.

TRIAL REGISTRATION

NCT02536690 (clinicaltrials.gov).

Comparing Labetalol and Nitroglycerine on Inducing Controlled Hypotension and Intraoperative Blood Loss in Rhinoplasty: A Single-Blinded Clinical Trial

Background

Uncontrolled bleeding during surgery is one of the main predisposing factors for failure of the surgeon and complications following rhinoplasty. The current study aimed at comparing the effects of nitroglycerine and labetalol on the induction of controlled hypotension and bleeding volume during septorhinoplasty.

Methods

The current randomized, controlled, clinical trial enrolled 60 patients candidate for septorhinoplasty at Firoozgar hospital in Tehran, Iran, in 2 equal groups receiving either 0.1 to 1 mcg/kg/minute nitroglycerine or 2 to 4 mg/minute labetalol to achieve a mean arterial blood pressure of about 60 to 65 mmHg. In case the targeted blood pressure was not achieved, isoflurane was added. Degree of bleeding was evaluated by the volume of suctioned blood and the blood remaining in surgical gauzes. Additionally, the surgeon's satisfaction with the surgical field was evaluated by a scoring system. The collected data were, then, compared between the study groups by the statistical methods.

Results

Based on the current study findings, systolic (P < 0.001), diastolic (P = 0.002), and the mean arterial blood pressures (P < 0.001) were significantly lower in the nitroglycerine group. Ninety percent of the patients in the labetalol group received isoflurane to achieve the targeted blood pressure defined as controlled hypotension. There was no significant difference between the groups regarding the volume of bleeding (P = 0.75); however, the surgeons were more satisfied with nitroglycerine than labetalol (P < 0.001).

Conclusions

It was concluded that nitroglycerine had a better effect, in comparison to labetalol, on inducing the controlled hypotension in septorhinoplasty.

The efficacy of Labetalol versus Nitroglycerin for induction of controlled hypotension during sinus endoscopic surgery. A prospective, double-blind and randomized study

OBJECTIVE

To assess the efficacy of labetalol versus nitroglycerin for induction of controlled hypotension during sinus endoscopic surgery.

DESIGN

A prospective, double-blind and randomized study.

SETTING

Carried out in operating room in university hospital.

PATIENTS

60 patients of both sexes, American Society of Anesthesiologists (ASA) physical status I and II, age range from 20 to 60years; scheduled for elective sinus endoscopic surgery under general anesthesia (GA).

INTERVENTIONS

Patients were divided into two groups (30 each). NTG group received nitroglycerin infusion at a dose of 2-5μg/kg/min, LAB group received labetalol infusion at a dose of 0.5-2mg/min.

MEASUREMENTS

Surgical condition was assessed by surgeon using average category scale (ACS) of 0-5, a value of 2-3 being ideal. In both groups mean arterial blood pressure (MAP) was gradually reduced till the ideal ACS for assessment of surgical condition, the target of ACS was 2-3 or lower.

RESULTS

Both studied drugs achieved desired hypotension and improved visualization of surgical field by decreasing bleeding in the surgical site, but ideal surgical conditions were created at mild hypotension (MAP 70-75) in LAB group while same conditions were created at MAP of 65-69mmHg in NTG group. Mean heart rate (HR) was significantly higher in NTG group as compared to LAB group. Blood loss decreased significantly in LAB group.

CONCLUSION

Both labetalol and NTG are effective and safe drugs for induction of controlled hypotension during sinus endoscopic surgery. While, labetalol was better as it offered optimum operative condition with mild decrease in blood pressure, decreased surgical bleeding and less tachycardia during the surgery.