Propofol causes more hypotension than etomidate in patients with severe aortic stenosis: a double-blind, randomized study comparing propofol and etomidate

Etomidate versus propofol for sedation in gastrointestinal endoscopy: A systematic review and meta-analysis of outcomes

BACKGROUND

Propofol is increasingly being used for sedation in gastrointestinal endoscopy; however, owing to its side effects, an alternative drug is needed. We aimed to compare the safety, satisfaction, and efficacy outcomes of etomidate versus propofol in patients undergoing gastrointestinal endoscopy, including advanced endoscopic procedures.

METHODS

We systematically searched Embase, PubMed, Cochrane Central Register of Controlled Trials, CINAHL (via EBSCO), China National Knowledge Infrastructure, and Web of Science (1946-April 2020) databases for randomized controlled trials of gastrointestinal endoscopy (upper gastrointestinal endoscopy, colonoscopy, and advanced endoscopy) using etomidate or propofol as sedatives. We pooled odds ratios (ORs) for the safety profile and patient and anesthesiologist satisfaction using mixed-effects conditional logistic models and standardized mean differences for efficiency outcomes using random-effects models.

RESULTS

Twenty-four studies involving 3875 patients were included. Compared with propofol, etomidate resulted in significantly reduced apnea (OR: 0.22; 95% confidence interval [CI]: 0.13-0.37; P < .001), hypoxemia (OR: 0.43; 95% CI: 0.35-0.54; P < .001), hypotension (OR: 0.20; 95% CI: 0.11-0.36; P < .001), and bradycardia (OR: 0.52; 95% CI: 0.30-0.91; P = .02) but led to increased myoclonus (OR: 8.54; 95% CI: 5.20-14.01; P < .001) and lowered anesthesiologist satisfaction (OR: 0.60; 95% CI: 0.39-0.91; P = .02).

CONCLUSION

Etomidate may be a good alternative to propofol for gastrointestinal endoscopy, especially advanced endoscopy. Etomidate appears to be safe as an inducer for hemodynamically unstable patients or older adult patients undergoing gastrointestinal endoscopy.

Hemodynamic changes during aortic valve surgery among patients with aortic stenosis

Introduction. Patients with severe aortic stenosis (AS) undergoing surgery are at increased risk of hypotension and hypoperfusion. Although treatable with inotropic agents or fluid, little is known about how these therapies affect central hemodynamics in AS patients under general anesthesia. We measured changes in central hemodynamics after dobutamine infusion and fluid bolus among patients with severe AS and associated these changes with preoperative echocardiography. Methods. We included 33 patients with severe AS undergoing surgical AVR. After induction of general anesthesia, hemodynamic measurements were obtained with a pulmonary artery catheter, including Cardiac index (CI), stroke volume index (SVi) and pulmonary capillary wedge pressure (PCWP). Measurements were repeated during dobutamine infusion, after fluid bolus and lastly after sternotomy. Results. General anesthesia resulted in a decrease in CI and SVi compared to preoperative values. During dobutamine infusion CI increased but mean SVi did not (38 ± 12 vs 37 ± 13 ml/m², p = .90). Higher EF and SVi before surgery and a larger decrease in SVi after induction of general anesthesia were associated with an increase in SVi during dobutamine infusion. After fluid bolus both CI, SVi (48 ± 12 vs 37 ± 13 ml/min/m², p < .0001) and PCWP increased. PCWP increased mostly among patients with a larger LA volume index. Conclusion. In patients with AS, CI can be increased with both dobutamine and fluid during surgery. Dobutamine's effect on SVI was highly variable and associated with baseline LVEF, and an increase in CI was mostly driven by an increase in heart rate. Fluid increased SVi at the cost of an increase in PCWP.

Peri-intubation Cardiovascular Collapse in Patients Who Are Critically Ill: Insights from the INTUBE Study

Rationale: Cardiovascular instability/collapse is a common peri-intubation event in patients who are critically ill. Objectives: To identify potentially modifiable variables associated with peri-intubation cardiovascular instability/collapse (i.e., systolic arterial pressure <65 mm Hg [once] or <90 mm Hg for >30 minutes; new/increased vasopressor requirement; fluid bolus >15 ml/kg, or cardiac arrest). Methods: INTUBE (International Observational Study to Understand the Impact and Best Practices of Airway Management In Critically Ill Patients) was a multicenter prospective cohort study of patients who were critically ill and undergoing tracheal intubation in a convenience sample of 197 sites from 29 countries across five continents from October 1, 2018, to July 31, 2019. Measurements and Main Results: A total of 2,760 patients were included in this analysis. Peri-intubation cardiovascular instability/collapse occurred in 1,199 out of 2,760 patients (43.4%). Variables associated with this event were older age (odds ratio [OR], 1.02; 95% confidence interval [CI], 1.02-1.03), higher heart rate (OR, 1.008; 95% CI, 1.004-1.012), lower systolic blood pressure (OR, 0.98; 95% CI, 0.98-0.99), lower oxygen saturation as measured by pulse oximetry/Fi_O2 before induction (OR, 0.998; 95% CI, 0.997-0.999), and the use of propofol as an induction agent (OR, 1.28; 95% CI, 1.05-1.57). Patients with peri-intubation cardiovascular instability/collapse were at a higher risk of ICU mortality with an adjusted OR of 2.47 (95% CI, 1.72-3.55), P < 0.001. The inverse probability of treatment weighting method identified the use of propofol as the only factor independently associated with cardiovascular instability/collapse (OR, 1.23; 95% CI, 1.02-1.49). When administered before induction, vasopressors (OR, 1.33; 95% CI, 0.84-2.11) or fluid boluses (OR, 1.17; 95% CI, 0.96-1.44) did not reduce the incidence of cardiovascular instability/collapse. Conclusions: Peri-intubation cardiovascular instability/collapse was associated with an increased risk of both ICU and 28-day mortality. The use of propofol for induction was identified as a modifiable intervention significantly associated with cardiovascular instability/collapse.Clinical trial registered with clinicaltrials.gov (NCT03616054).

The hemodynamic stability of remimazolam compared with propofol in patients undergoing endoscopic submucosal dissection: A randomized trial

Objective

Hypotension is common in propofol anesthesia. Whether remimazolam could reduce intraoperative hypotension remains unknown. We therefore tested the primary hypothesis that remimazolam reduces the incidence of intraoperative hypotension compared with propofol in adult patients undergoing endoscopic submucosal dissection (ESD) surgery.

Materials and methods

We conducted a prospective trial to compare patients who received either remimazolam or propofol bolus induction and thereafter intravenous infusion. The hemodynamic parameters were measured using CNAP® Monitor 500 system. Our primary analysis was to compare the incidence of hypotension defined as systolic blood pressure below 90 mmHg between remimazolam and propofol during the whole anesthesia period.

Results

The incidence of hypotension decreased by 50%, from 67.9% in propofol group to 32.1% in remimazolam group (p &lt; 0.01). Patients received less amount of intraoperative phenylephrine in the remimazolam group than the propofol group (0 [0–40] μg vs. 80 [0–200] μg, p &lt; 0.01). Time-weighted average and cumulative time of hypotension was lower in remimazolam group compared with propofol group (p &lt; 0.05). Cardiac output continuously measured by CNAP was preserved much better in remimazolam group compared with propofol group (p = 0.01), while systemic vascular resistance did not differ between the groups. The median time from discontinuation until full alertness was 4 [3–11.8] min in the remimazolam group compared with 15 [12.0–19.8] min in the propofol group (p &lt; 0.01).

Conclusion

Remimazolam has better hemodynamic stability than propofol in adult patients undergoing ESD surgery. The benefits of remimazolam on hemodynamic stability and hypotension prevention may be partly contributed to its better preservation of cardiac output.

Clinical Trial Registration

[http://www.chictr.org.cn/com/25/showproj.aspx?proj=61104], identifier [ChiCTR2000037975].

Remimazolam for induction of anesthesia in elderly patients with severe aortic stenosis: a prospective, observational pilot study

Background

Remimazolam, a novel benzodiazepine, has been reported to cause less hypotension than propofol during induction of anesthesia. Therefore, remimazolam might be a valuable option in elderly patients with severe aortic stenosis who are considered to be the most vulnerable to hemodynamic instability. We aimed to evaluate the feasibility and hemodynamic effects of remimazolam as an induction agent in elderly patients with severe aortic stenosis.

Methods

This prospective, open-label, single-arm, observational pilot study was conducted in a university hospital between November 2020 and April 2021. We included 20 patients aged 65 years or older scheduled for transcatheter or surgical aortic valve replacement for severe aortic stenosis under general anesthesia. Patients were administered intravenous remimazolam infusion at 6 mg/kg/h combined with 0.25 μg/kg/min of remifentanil infusion. The primary outcome was the vasopressor dosage between the induction of anesthesia and the completion of tracheal intubation. The secondary outcomes included hemodynamic changes, bispectral index changes, and the time from the start of remimazolam infusion to loss of consciousness. We also recorded awareness during anesthesia induction and serious adverse events related to death, life-threatening events, prolonged hospitalizations, and disability due to permanent damage.

Results

Twenty patients aged 84 [79–86] (median [interquartile range]) with American Society of Anesthesiologists physical status 4 were analyzed. Ephedrine 0 [0–4] mg and phenylephrine 0.1 [0–0.1] mg were administered to 14/20 patients (3 doses in 1 patient, 2 doses in 4 patients, and one dose in 9 patients). Loss of consciousness was achieved at 80 [69–86] s after the remimazolam infusion was started. The mean arterial pressure decreased gradually after loss of consciousness but recovered immediately after tracheal intubation. The bispectral index values gradually decreased and reached < 60 at 120 s after loss of consciousness. Neither awareness during induction of anesthesia nor serious adverse events, such as severe bradycardia (< 40 bpm), life-threatening arrhythmia, myocardial ischemia, or anaphylactic reactions were observed.

Conclusions

Remimazolam could be used as an induction agent with timely bolus vasopressors in elderly patients with severe aortic stenosis.

Trial registration

UMIN Clinical Trials Registry, identifier UMIN000042318.

Anaesthetic management using remimazolam in a patient with severe aortic stenosis: a case report

Background

The administration of general anaesthesia in patients with aortic stenosis (AS) requires careful attention to haemodynamics. We used remimazolam for the induction and maintenance of anaesthesia in a woman with severe AS undergoing a total mastectomy.

Case presentation

An 81-year-old woman with severe AS was scheduled to undergo a total mastectomy. We decided to administer total intravenous anaesthesia with remimazolam to minimize haemodynamic changes. Although the patient showed transient hypotension after anaesthesia induction, the cardiac index was preserved with a low dose of continuous noradrenaline. The anaesthesia was then safely maintained without a decrease in the patient’s cardiac index.

Conclusions

General anaesthesia using remimazolam preserved cardiac output in this patient; therefore, remimazolam can be safely used to avoid the risk of cardiac suppression in patients with severe AS.

Effect of remimazolam induction on hemodynamics in patients undergoing valve replacement surgery: A randomized, double-blind, controlled trial

Background

The stability of hemodynamics during anesthesia induction in patients undergoing valve replacement surgery is particularly important. Remimazolam is a new type of benzodiazepine drug, with supposed advantages of rapid induction, rapid recovery, stable hemodynamics, and mild respiratory inhibition.

Aim

To evaluate the effect of remimazolam anesthesia induction on hemodynamics in patients undergoing valve replacement surgery.

Methods

This randomized, double‐blind, controlled trial enrolled consecutive patients undergoing mitral valve replacement (MVR)/aortic valve replacement (AVR)/double‐valve replacement (DVR) surgery on cardiopulmonary bypass (CPB). The study was conducted according to the Consolidated Standards of Reporting Trials statement. Participants were randomly assigned to receive either remimazolam or propofol induction of 30 patients each. All patients, data collectors, and data analyzers were blinded to the group allocation. The primary outcomes were the fluctuations in hemodynamic parameters (the difference of maximum or minimum heart rate to baseline, ▲HR, the difference of maximum or minimum mean arterial pressure to baseline, ▲MAP), the occurrence of cardiovascular events (hypotension, severe bradycardia), and the cumulative norepinephrine doses used per patient, averaged per group during induction. The secondary outcomes were hemodynamic parameters (heart rate, HR, mean arterial pressure, MAP, bispectral index, BIS, plasma lactic acid, Lac, and blood glucose, Glu values).

Results

A total of 60 patients with heart valve replacement were included in the final analysis, with 30 patients in each group. The ▲MAP was significantly lower in the remimazolam group than in the propofol group during induction (p < .05). The incidences of hypotension and the cumulative norepinephrine doses used per patient, averaged per group during induction were significantly lower in the remimazolam group than in the propofol group (p < .05).

Conclusion

Remimazolam may be safe and effective for induction and may as an alternative to propofol during anesthesia induction in patients undergoing valve replacement surgery.

CON: Propofol Is Better Than Etomidate for Induction in Cardiac Surgical Patients

There is an ongoing debate regarding the choice of ideal induction agent between propofol and etomidate for cardiac surgical patients. Etomidate appears to be better than propofol as the induction agent due to the superior hemodynamic stability. However, the adrenal suppression due to etomidate can pose challenges to the anesthesiologist in certain clinical situations.

Anesthetic Induction With Etomidate in Cardiac Surgical Patients: A PRISMA-Compliant Systematic Review and Meta-Analysis

OBJECTIVE

This meta-analysis aimed to systematically review the effects of etomidate (ETM) during anesthetic induction on patients undergoing cardiac surgery.

DESIGN

Systematic review and meta-analysis.

SETTING

Operating room.

PARTICIPANTS

Patients undergoing cardiac surgery.

INTERVENTIONS

ETM or control drugs.

MEASUREMENTS AND MAIN RESULTS

PubMed, Cochrane Library, OVID, and EMBASE were searched through August 31, 2020. Primary outcomes included hemodynamic profiles and stress responses. Secondary outcomes included morbidity, mortality, and postoperative recovery. For continuous/dichotomous variables, treatment effects were calculated as weighted mean difference (WMD)/odds ratio (OR) and 95% confidence interval (CI). A database search yielded 18 randomized controlled trials including 1,241 patients. The present meta-analysis demonstrated that ETM-anesthetized patients had lower heart rates (WMD, -3.31; 95% CI -5.43 to -1.19; p = 0.002), higher blood pressures (systolic blood pressure: WMD, 12.02; 95% CI 6.24 to 17.80; p < 0.0001; diastolic blood pressure: WMD, 5.23; 95% CI 2.39 to 8.08; p = 0.0003; mean arterial pressure (MAP): WMD, 8.64; 95% CI 5.85 to 11.43; p < 0.00001), less requirement for vasopressor (OR, 0.26; 95% CI 0.15 to 0.44; p < 0.00001), and more nitroglycerin usage (OR, 14.89; 95% CI 4.92 to 45.08; p < 0.00001) during anesthetic induction. Current meta-analysis also demonstrated that single-dose ETM lowered cortisol levels transiently and did not have a significant effect on endogenous norepinephrine and epinephrine levels and was not associated with increased postoperative inotrope and/or vasopressor requirement. Additionally, the meta-analysis suggested that ETM anesthesia was associated with neither increased mortality nor morbidity, except a higher incidence of transient adrenal insufficiency in ETM recipients.

CONCLUSION

The present meta-analysis suggested that single-dose ETM during anesthetic induction could be associated with more stable hemodynamics, transient and reversible lower cortisol levels, and a higher adrenal insufficiency incidence, but not worse outcomes in cardiac surgical patients.

The effect of cardiac output on the pharmacokinetics and pharmacodynamics of propofol during closed-loop induction of anesthesia

BACKGROUND AND OBJECTIVE

Intraoperative hemodynamic stability is essential to safety and post-operative well-being of patients and should be optimized in closed-loop control of anesthesia. Cardiovascular changes inducing variations in pharmacokinetics may require dose modification. Rigorous investigational tools can strengthen current knowledge of the anesthesiologists and support clinical practice. We quantify the cardiovascular response of high-risk patients to closed-loop anesthesia and propose a new application of physiologically-based pharmacokinetic-pharmacodynamic (PBPK-PD) simulations to examine the effect of hemodynamic changes on the depth of hypnosis (DoH).

METHODS

We evaluate clinical hemodynamic changes in response to anesthesia induction in high-risk patients from a study on closed-loop anesthesia. We develop and validate a PBPK-PD model to simulate the effect of changes in cardiac output (CO) on plasma levels and DoH. The wavelet-based anesthetic value for central nervous system monitoring index (WAV_CNS) is used as clinical end-point of propofol hypnotic effect.

RESULTS

The median (interquartile range, IQR) changes in CO and arterial pressure (AP), 3 min after induction of anesthesia, are 22.43 (14.82-36.0) % and 26.60 (22.39-35.33) % respectively. The decrease in heart rate (HR) is less marked, i.e. 8.82 (4.94-12.68) %. The cardiovascular response is comparable or less enhanced than in manual propofol induction studies. PBPK simulations show that the marked decrease in CO coincides with high predicted plasma levels and deep levels of hypnosis, i.e. WAV_CNS < 40. PD model identification is improved using the PBPK model rather than a standard three-compartment PK model. PD simulations reveal that a 30% drop in CO can cause a 30% change in WAV_CNS.

CONCLUSIONS

Significant CO drops produce increased predicted plasma concentrations corresponding to deeper anesthesia, which is potentially dangerous for elderly patients. PBPK-PD model simulations allow studying and quantifying these effects to improve clinical practice.

Difficult Intubation due to Penetrating Trauma from a Crossbow Bolt

We present the case of a patient with penetrating neck and craniofacial trauma from a self-inflicted crossbow bolt injury. This case highlights the challenges involved in prehospital airway management related to an in situ foreign object penetrating the oral cavity. We review the complications associated with such injuries and considerations for effective prehospital airway management.

The effect of etomidate or propofol on brainstem function during anesthesia induction: a bispectral index-guided study

Purpose

To compare the effect of etomidate versus propofol infusion on hemodynamic profiles, spontaneous breathing, and corneal reflex during the induction of anesthesia.

Methods

Adult patients (n=80) were randomized to receive etomidate (Group E, n=40) or propofol (Group P, n=40) infusion during anesthesia induction. Throughout induction, mean blood pressure and heart rate were monitored. Time to loss of consciousness (LOC), bispectral index (BIS), existence of spontaneous breathing, and corneal reflex at LOC were recorded.

Results

Fewer changes in hemodynamic profile occurred in Group E compared with Group P during induction of anesthesia. The mean time to LOC was shorter with etomidate than propofol (129.5 s vs 189.5 s, P<0.0001). BIS was lower in Group E compared with Group P at LOC (46.3 vs 52.9, P=0.0141). More patients exhibited spontaneous breathing in Group E compared with Group P at LOC (80% vs 17.5%, P<0.0001). Similarly, more patients maintained corneal reflex in Group E compared with Group P (34 patients vs 4 patients, P<0.0001). The incidence of etomidate-induced myoclonus was 17.5%.

Conclusion

Compared with propofol infusion, etomidate infusion during anesthesia induction had fewer effects on the hemodynamic profile of patients. Among patients who received etomidate, the BIS value was lower at LOC, and more patients displayed spontaneous breathing and corneal reflex.

Trial Registry Number

China Clinical Research Information Service, ChiCTR-IOR-17011050

Editor’s Choice- Sedation in the coronary intensive care unit: An adapted algorithm for critically ill cardiovascular patient

In the current era, cardiovascular intensive care units care for more complex patients who are far sicker than historical post-myocardial infarction patients, and sedation has become a common intervention in these units. Current sedation best practices derive mainly from non-cardiac units which limits their generalization to the critically ill cardiac patient. Thus, a great variability in sedation protocols, especially the selection of sedative agents, is commonly seen in daily practice across cardiac units. We present an updated review on sedation in cardiovascular critical care medicine with emphasis on the hemodynamic impact. The goal of this review is to generate a general sedation algorithm specific for the cardiac patient.

Anaesthetic induction with etomidate in cardiac surgery: A randomised controlled trial

BACKGROUND

Etomidate is perceived as preserving haemodynamic stability during induction of anaesthesia. It is also associated with adrenocortical dysfunction. The risk/benefit relationship is controversial.

OBJECTIVES

We tested the hypotheses that single-dose etomidate increases cumulative vasopressor requirement, time to extubation and length of stay in the ICU.

DESIGN

Double-blind randomised controlled trial.

SETTING

Bern University Hospital, Switzerland, from November 2006 to December 2009.

PATIENTS

There were 90 patients undergoing coronary artery bypass grafts (CABG) and 40 patients undergoing mitral valve surgery (MVS). Reasons for noninclusion were known adrenocortical insufficiency, use of etomidate or propofol within 1 week preoperatively, use of glucocorticoids within 6 months preoperatively, severe renal or liver dysfunction, or carotid stenosis.

INTERVENTIONS

CABG patients were allocated randomly to receive either etomidate 0.15 mg kg with placebo, propofol 1.5 mg kg with placebo or etomidate 0.15 mg kg with hydrocortisone (n = 30 in each arm). Risk stratification (low vs. high) was achieved by block randomisation. MVS patients received either etomidate 0.15 mg kg or propofol 1.5 mg kg (n = 20 in each arm).

MAIN OUTCOME MEASURES

Cumulative vasopressor requirements, incidence of adrenocortical insufficiency, length of time to extubation and length of stay in ICU.

RESULTS

Cumulative vasopressor requirements 24 h after induction did not differ between treatments in patients who underwent CABG, whereas more noradrenaline was used in MVS patients following propofol induction (absolute mean difference 5.86 μg kg over 24 h P = 0.047). The incidence of relative adrenocortical insufficiency was higher after etomidate alone than propofol (CABG 83 vs. 37%, P < 0.001; MVS: 95 vs. 35%, P < 0.001). The time to extubation, length of stay in ICU and 30-day mortality did not differ among treatments. Within low and high-risk subgroups, no differences in vasopressor use or outcomes were found.

CONCLUSION

In elective cardiac surgery, laboratory indicators of etomidate-induced adrenal insufficiency do not translate into increased vasopressor requirement or inferior early outcomes.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT 00415701.

Etomidate versus propofol sedation for complex upper endoscopic procedures: a prospective double-blinded randomized controlled trial

BACKGROUND AND AIMS

Although a growing body of evidence demonstrates that propofol-induced deep sedation can be effective and performed safely, cardiopulmonary adverse events have been observed frequently. Etomidate is a new emerging drug that provides hemodynamic and respiratory stability, even in high-risk patient groups. The objective of this study was to compare safety and efficacy profiles of etomidate and propofol for endoscopic sedation.

METHODS

A total of 128 patients undergoing EUS were randomized to receive either etomidate or propofol blinded administered by a registered nurse. The primary outcome was the proportion of patients with any cardiopulmonary adverse events.

RESULTS

Overall cardiopulmonary adverse events were identified in 22 patients (34.38%) of the etomidate group and 33 patients (51.56%) of the propofol group, without significant difference (P = .074). However, the incidence of oxygen desaturation (4/64 [6.25%] vs 20/64 [31.25%]; P =.001) and respiratory depression (5/64 [7.81%] vs 21/64 [32.81%]; P =.001) was significantly lower in the etomidate group than in the propofol group. The frequency of myoclonus was significantly higher in the etomidate group (22/64 [34.37%]) compared with the propofol group (8/64 [12.50%]) (P =.012). Repeated measure analysis of variance revealed significant effects of sedation group and time on systolic blood pressure (etomidate group greater than propofol group). Physician satisfaction was greater in the etomidate group than in the propofol group.

CONCLUSIONS

Etomidate administration resulted in fewer respiratory depression events and had a better sedative efficacy than propofol; however, it was more frequently associated with myoclonus and increased blood pressure during endoscopic procedures. (Clinical trial registration number: KCT0001701.).

Sedative-hypnotic Binding to 11β-hydroxylase

BACKGROUND

Etomidate potently suppresses adrenocortical steroid synthesis with potentially deleterious consequences by binding to 11β-hydroxylase and inhibiting its function. The authors hypothesized that other sedative-hypnotics currently in clinical use or under development (or their metabolites) might bind to the same site at clinically relevant concentrations. The authors tested this hypothesis by defining etomidate's affinity for this site and the potencies with which other sedative-hypnotics (and their metabolites) inhibit etomidate binding.

METHODS

H-etomidate's binding to adrenal membranes from Sprague-Dawley rats was characterized with a filtration assay, and its dissociation constant was defined using saturation and homologous ligand competition approaches. Half-inhibitory concentrations of sedative-hypnotics and metabolites were determined from the reduction in specific H-etomidate binding measured in the presence of ranging sedative-hypnotic and metabolite concentrations.

RESULTS

Saturation and homologous competition studies yielded H-etomidate dissociation constants of 40 and 21 nM, respectively. Half-inhibitory concentrations of etomidate and cyclopropyl methoxycarbonyl metomidate (CPMM) differed significantly (26 vs. 143 nM, respectively; P < 0.001), and those of the carboxylic acid (CA) metabolites etomidate-CA and CPMM-CA were greater than or equal to 1,000× higher than their respective parent hypnotics. The half-inhibitory concentration of dexmedetomidine was 2.2 µM, whereas those of carboetomidate, ketamine, and propofol were greater than or equal to 50 µM.

CONCLUSION

Etomidate's in vitro dissociation constant for 11β-hydroxylase closely approximates its in vivo adrenocortical half-inhibitory concentration. CPMM produces less adrenocortical suppression than etomidate not only because it is metabolized faster but also because it binds to 11β-hydroxylase with lower affinity. Other sedative-hypnotics and metabolites bind to 11β-hydroxylase and inhibit etomidate binding only at suprahypnotic concentrations.

Effect of etomidate and propofol induction on hemodynamic and endocrine response in patients undergoing coronary artery bypass grafting/mitral valve and aortic valve replacement surgery on cardiopulmonary bypass

INTRODUCTION

The concerns for induction of anaesthesia in patients undergoing cardiac surgery include hemodynamic stability, attenuation of stress response and maintenance of balance between myocardial oxygen demand and supply. Various Intravenous anaesthetic agents like Thiopentone, Etomidate, Propofol, Midazolam, and Ketamine have been used for anesthetizing patients for cardiac surgeries. However, many authors have expressed concerns regarding induction with thiopentone, midazolam and ketamine. Hence, Propofol and Etomidate are preferred for induction in these patients. However, these two drugs have different characteristics. Etomidate is preferred for patients with poor left ventricular (LV) function as it provides stable cardiovascular profile. But there are concerns about reduction in adrenal suppression and serum cortisol levels. Propofol, on the other hand may cause a reduction in systemic vascular resistance and subsequent hypotension. Thus, this study was conducted to compare induction with these two agents in cardiac surgeries.

METHODS

Baseline categorical and continuous variables were compared using Fisher's exact test and student's t test respectively. Hemodynamic variables were compared using student's t test for independent samples. The primary outcome (serum cortisol and blood sugar) of the study was compared using Wilcoxon Rank Sum test. The P value less than 0.05 was considered significant.

RESULTS

Etomidate provides more stable hemodynamic parameters as compared to Propofol. Propofol causes vasodilation and may result in drop of systematic BP. Etomidate can therefore be safely used for induction in patients with good LV function for CABG/MVR/AVR on CPB without serious cortisol suppression lasting more than twenty-four hours.

Etomidate Anesthesia during ERCP Caused More Stable Haemodynamic Responses Compared with Propofol: A Randomized Clinical Trial

BACKGROUND

Propofol may result in hypotension and respiratory depression, while etomidate is considered to be a safe induction agent for haemodynamically unstable patients because of its low risk of hypotension. We hypothesized that etomidate anesthesia during ERCP caused more stable haemodynamic responses compared with propofol. The primary endpoint was to compare the haemodynamic effects of etomidate vs. propofol in ERCP cases. The secondary endpoint was overall survival.

METHODS

A total of 80 patients undergoing ERCP were randomly assigned to an etomidate or propofol group. Patients in the etomidate group received etomidate induction and maintenance during ERCP, and patients in the propofol group received propofol induction and maintenance. Cardiovascular parameters and procedure-related time were measured and recorded during ERCP.

RESULTS

The average percent change to baseline in MBP was -8.4±7.8 and -14.4±9.4 with P = 0.002, and in HR was 1.8±16.6 and 2.4±16.3 with P = 0.874 in the etomidate group and the propofol group, respectively. MBP values in the etomidate group decreased significantly less than those in the propofol group (P<0.05). The ERCP duration and recovery time in both groups was similar. There was no significant difference in the survival rates between groups ( p = 0.942).

CONCLUSIONS

Etomidate anesthesia during ERCP caused more stable haemodynamic responses compared with propofol.

Anesthesia for stem cell transplantation in autistic children: A prospective, randomized, double-blind comparison of propofol and etomidate following sevoflurane inhalation

The objective of the present study was to comparatively investigate the feasibility and safety of etomidate and propofol use following sevoflurane inhalation in autistic children during the intrathecal transplantation of stem cells. The patients selected were 60 autistic children with American Society of Anesthesiologists physical status I, who were aged between two and 12 years and scheduled for stem cell transplantation. The children received an inhalation induction of 8% sevoflurane, followed by intravenous injection of etomidate (0.2 mg/kg) in group E and propofol (2 mg/kg) in group P (n=30/group). Supplemental doses of 0.1 mg/kg etomidate or 1 mg/kg propofol were used until a deep sedation was obtained. The heart rate (HR), mean arterial pressure, oxygen saturation, respiratory rate, Ramsay sedation score (RSS) and recovery time were monitored continuously. Following anesthesia, blood pressure and HR measurements were significantly decreased in group P compared with the baseline (P<0.01) and group E values at the same time-points (P<0.05). The occurrence of adverse effects, such as respiratory depression, bradycardia, hypotension and pain on injection, was significantly higher in group P than that in group E, whereas the incidence of myoclonus in group E was significantly higher than that in group P (P<0.01). No significant differences in anesthesia induction, surgery duration, recovery time, RSS and physician satisfaction were observed between the two groups. In conclusion, sevoflurane-etomidate combinations resulted in more stable hemodynamic responses and relatively fewer adverse effects compared with propofol injection following sevoflurane inhalation and may therefore be more suitable for the induction of short-term anesthesia in autistic children during stem cell transplantation.

Predictors of severe hypotension in neurocritical care patients sedated with propofol

INTRODUCTION

Propofol is used extensively in neurocritical care (NCC) due to its pharmacologic properties allowing for facilitation of serial neurologic examinations. Despite widespread use, few studies have identified risk factors for hypotension in these patients. We aimed to determine predictors of hypotension in NCC patients sedated with propofol.

METHODS

This retrospective, multicenter study evaluated 237 patients at two academic medical centers, both with dedicated NCC teams led by board-certified neurointensivists. Univariate analyses were performed to determine risk factors associated with severe hypotension during sedation with propofol. Multivariable analysis was performed to determine variables independently associated with hypotension, defined as a mean arterial pressure (MAP) less than 60 mmHg.

RESULTS

There was an average maximum reduction in MAP of 28.8 % after propofol initiation in the entire cohort. Severe hypotension developed in 62 (26.2 %) patients to a median nadir MAP of 56 mmHg. Those who developed severe hypotension had a longer median duration of mechanical ventilation (5.0 vs. 3.6 days; p = 0.01) and an increased in-hospital mortality (38.7 vs. 24.0 %; p = 0.03). Multivariable logistic regression analysis identified increasing number of changes to the propofol infusion rate, baseline MAP 60-70 mmHg, and need for renal replacement therapy (RRT) as factors independently associated with hypotension.

CONCLUSIONS

Multiple factors predicted hypotension in NCC patients receiving propofol. Clinicians should use propofol cautiously in patients with a lower baseline MAP or receiving RRT. Development of protocols related to the frequency of dose titrations is also recommended to prevent this avoidable complication.

Optimal perioperative management of arterial blood pressure

Perioperative blood pressure management is a key factor of patient care for anesthetists, as perioperative hemodynamic instability is associated with cardiovascular complications. Hypertension is an independent predictive factor of cardiac adverse events in noncardiac surgery. Intraoperative hypotension is one of the most encountered factors associated with death related to anesthesia. In the preoperative setting, the majority of antihypertensive medications should be continued until surgery. Only renin-angiotensin system antagonists may be stopped. Hypertension, especially in the case of mild to moderate hypertension, is not a cause for delaying surgery. During the intraoperative period, anesthesia leads to hypotension. Hypotension episodes should be promptly treated by intravenous vasopressors, and according to their etiology. In the postoperative setting, hypertension predominates. Continuation of antihypertensive medications and postoperative care may be insufficient. In these cases, intravenous antihypertensive treatments are used to control blood pressure elevation.

Etomidate--a review of robust evidence for its use in various clinical scenarios

Etomidate is an intravenous hypnotic with a favourable clinical profile in haemodynamic high-risk scenarios. Currently, there is an active debate about the clinical significance of the drug's side effects and its overall risk-benefit ratio. Etomidate-induced transient adrenocortical suppression is well documented and has been associated with increased mortality in sepsis. In surgical patients at risk of hypotensive complications, however, a review of current literature provides no robust evidence to contraindicate a single-bolus etomidate induction. Large randomised controlled trials as well as additional observational data are required to compare safety of etomidate and its alternatives.

Predictors of severe hypotension in neurocritical care patients sedated with propofol

INTRODUCTION

Propofol is used extensively in neurocritical care (NCC) due to its pharmacologic properties allowing for facilitation of serial neurologic examinations. Despite widespread use, few studies have identified risk factors for hypotension in these patients. We aimed to determine predictors of hypotension in NCC patients sedated with propofol.

METHODS

This retrospective, multicenter study evaluated 237 patients at two academic medical centers, both with dedicated NCC teams led by board-certified neurointensivists. Univariate analyses were performed to determine risk factors associated with severe hypotension during sedation with propofol. Multivariable analysis was performed to determine variables independently associated with hypotension, defined as a mean arterial pressure (MAP) less than 60 mmHg.

RESULTS

There was an average maximum reduction in MAP of 28.8 % after propofol initiation in the entire cohort. Severe hypotension developed in 62 (26.2 %) patients to a median nadir MAP of 56 mmHg. Those who developed severe hypotension had a longer median duration of mechanical ventilation (5.0 vs. 3.6 days; p = 0.01) and an increased in-hospital mortality (38.7 vs. 24.0 %; p = 0.03). Multivariable logistic regression analysis identified increasing number of changes to the propofol infusion rate, baseline MAP 60-70 mmHg, and need for renal replacement therapy (RRT) as factors independently associated with hypotension.

CONCLUSIONS

Multiple factors predicted hypotension in NCC patients receiving propofol. Clinicians should use propofol cautiously in patients with a lower baseline MAP or receiving RRT. Development of protocols related to the frequency of dose titrations is also recommended to prevent this avoidable complication.

Severe aortic stenosis and subarachnoid hemorrhage: Anesthetic management of lethal combination

Despite advances in various modalities of management, subarachnoid hemorrhage (SAH) continues to be associated with high mortality, which is further increased by associated comorbidities. Aortic stenosis (AS) is one such disease which can further complicate the course of SAH. We recently managed a known patient of severe AS, who presented with aneurysmal SAH. Patient was planned for eurovascular intervention. With proper assessment and planning, patient was managed with favorable outcome despite the restrictions faced in the neurovascular intervention laboratory.

Bispectral index-guided induction of general anaesthesia in patients undergoing major abdominal surgery using propofol or etomidate: a double-blind, randomized, clinical trial

BACKGROUND

In a double-blind, randomized trial, we compared the haemodynamic effects of a bispectral index (BIS)-guided etomidate and propofol infusion for anaesthesia induction in patients undergoing major abdominal surgery.

METHODS

Forty-six patients were randomly assigned to two groups based on the induction of anaesthesia, performed with a BIS value of 60 titrated infusion of etomidate (E group) or propofol (P group). Mean arterial pressure (MAP), cardiac index (CI), heart rate, and systemic vascular resistance index (SVRI) measurements were taken 1 min before induction and recorded at 1-min intervals for 20 min. P<0.05 was considered statistically significant.

RESULTS

Before intubation, no significant differences between the two groups regarding the haemodynamics were noticed. At intubation and up to 7 min after intubation MAP (P=0.019) was significantly higher in the E group. CI was significantly higher in the E group with respect to the P group 2, 6, and 7 min after intubation. Twenty-three patients developed complications. The incidence of hypotension was higher in the P group than that in the E group (8 vs 3; P=0.08), and the incidence of hypertension was significantly higher in the E group than that in the P group (10 vs 2; P=0.007).

CONCLUSIONS

Our study showed that the use of propofol resulted in less hypertension and tachycardia at and after intubation than etomidate. But even with the reduced doses given with the BIS-guided protocol, it often caused significant hypotension.