Relative adrenal insufficiency and hemodynamic status in cardiopulmonary bypass surgery patients. A prospective cohort study

Is Preoperative Adrenal Insufficiency Screening Necessary for Cardiovascular Thoracic Surgery Patients?

Background: The association between adrenal insufficiency (AI) and the treatment outcomes of cardiothoracic surgery patients has been little reported. The aims of this study were to investigate the incidence of AI and to compare the post-surgical outcomes of patients with perioperatively treated AI and patients with a normal adrenal response. Methods: A 1.5-year prospective study was conducted in 98 patients scheduled for cardiothoracic surgery. Patients were categorized as either AI or normal-adrenal-response patients. Those with AI were treated with stress doses of glucocorticoid perioperatively. The post-surgical outcomes of patients with AI and of those with a normal adrenaline response were analyzed using multivariable analysis. Results: The overall incidence of AI was 34.7%. There were no statistically significant differences in post-surgical outcomes, including prolonged hospital stay, postoperative infection, prolonged inotropic drug use and relative AI, between the two groups. Only the rate of hyperglycemia requiring insulin infusion was significantly higher in the AI group than in the non-AI group (OR = 14.15, 95% CI = 1.44-138.60, p = 0.02). Conclusions: The proper diagnosis and management of AI can result in surgical outcomes in AI patients comparable to those of normal-adrenal-response patients. Non-life-threatening hyperglycemia requiring insulin infusion was found only in the AI group.

Effect of remimazolam tosilate versus etomidate on hemodynamics in patients undergoing valve replacement surgery: study protocol for a randomized controlled trial

BACKGROUND

Patients with a history of cardiac disease are prone to develop cardiovascular adverse events such as hypotension, hypertension, and tachycardia during anesthesia induction. Therefore, hemodynamic stability is one of the most important concerns for induction of anesthesia in patients undergoing cardiac surgery. Remimazolam tosilate is a new, ultra-short-acting benzodiazepine agent, with the advantages of rapid onset, rapid offset, and minimal cardiorespiratory depression. We aim to compare the effect of remimazolam tosilate and etomidate on hemodynamics during anesthesia induction in patients undergoing valve replacement surgery.

METHODS/DESIGN

The trial is a prospective, randomized, double-blinded, controlled, single-center trial to compare the effect of remimazolam tosilate and etomidate on hemodynamics in patients undergoing valve replacement surgery. One hundred seventeen patients undergoing selective valve replacement surgery between January 1, 2022, and December 31, 2023, will be enrolled and randomly allocated into one of three groups: low-dose remimazolam group (Group LR), high-dose remimazolam group (Group HR), or etomidate group (Group E). The primary outcome is hemodynamic fluctuations during anesthesia induction (the difference between mean arterial pressure [MAP] to baseline, ▴MAP; and the difference between maximum or minimum heart rate [HR] and baseline, ▴HR). Secondary outcomes include the incidence of adverse cardiovascular events (hypotension, severe bradycardia, hypertension, tachycardia, and arrhythmia), the cumulative doses of vasoactive drugs used per patient, incidence and degree of injection pain and myoclonus, blood glucose values, and vital signs at different time points.

DISCUSSION

This research will determine the effectiveness and safety of remimazolam tosilate induction on hemodynamics in patients undergoing valve replacement surgery.

TRIAL REGISTRATION

www.chictr.org .cn identifier ChiCTR2100052535 . Registered on 17th Dec 2021, http://www.chictr.org.cn/ ).

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.

Pro: Propofol Is a Better Induction Agent than Etomidate

Induction refers to the start of anesthesia when the patient is rendered unconscious. The intravenous induction agents allow the patient to experience a pleasant loss of consciousness while also rapidly achieving surgical levels of anesthesia. An ideal induction agent must have a rapid onset and offset of action, and must be easy to administer and without significant side effects. Currently, the commonest used agents include sodium pentothal, propofol, ketamine, and etomidate. Unfortunately, none of these agents possess the characteristics of an ideal induction agent. In this article, we will discuss the merits of propofol as an ideal induction agent for cardiac surgery and how it scores over etomidate for the same purpose.

Use of etomidate in patients with heart failure undergoing noncardiac surgery

BACKGROUND

Patients with symptomatic and asymptomatic heart failure undergoing noncardiac surgery may benefit from the haemodynamic profile of etomidate. However, the safety of etomidate in this population is unknown. We examined anaesthesiologist variation in etomidate use and assessed its safety using an instrumental variable approach to account for differences in treatment selection.

METHODS

A retrospective cohort study of 19 714 patients with heart failure undergoing noncardiac surgery at two tertiary care institutions from January 2006 to December 2017 was performed. The proportion of etomidate use among 294 anaesthesiologists was examined and adjusted risk differences (aRD) for in-hospital and 30-day mortality were calculated using physician preference for etomidate as an instrumental variable.

RESULTS

Etomidate was used in 14.3% (2821/19 714) of patients. Preference for etomidate varied substantially among individual anaesthesiologists with the lowest and highest quartile users using etomidate in 0-4.7% and 20.4-66.7% of their own heart failure patients, respectively. The adjusted instrumental variable analysis showed no significant differences in the risk of in-hospital (aRD -0.2%; 95% confidence interval, -2.4%-1.9%; P=0.83) or 30 day mortality (aRD 0.2%; 95% confidence interval, -2.5%-2.9%; P=0.90). Anaesthesiologists with higher preferences for etomidate were more experienced (greater heart failure and total case volume) than anaesthesiologists with lower preferences for etomidate.

CONCLUSIONS

We found substantial variability in anaesthesiologists' preference for etomidate for use in patients with heart failure undergoing noncardiac surgery. There was no association between etomidate use and in-hospital or 30-day mortality. Etomidate is not inferior to other currently used options for induction of general anaesthesia in patients with heart failure.

Assessment of adrenal reserve and secretion of cortisol in patients over 60 years of age undergoing cardiac surgery

Introduction

Cortisol level affects the prognosis of patients after cardiac surgery. Meanwhile, there are no clear guidelines for steroid supplementation after a cardiac operation. The relationship between age and blood cortisol levels has not been finally clarified.

Aim

Assessment of adrenal reserve and secretion of cortisol in patients over 60 years of age undergoing cardiac surgery.

Material and methods

The study included 20 patients of both sexes referred for cardiac surgery. A short ACTH synthetic stimulation test was carried out. Assessment of cortisol secretion was carried out in the morning on the day of surgery and the 1^st, 2^nd and 4^th days after surgery in blood samples.

Results

A result within the normal range for the adrenal reserve was found in 19 of the 20 patients enrolled in the study. The short Synacthen test predicted postoperative secretion of cortisol (p = 0.04, r = 0.047). A relationship between secretion of cortisol and patients’ age was observed (p = 0.03, r = 0.48). The concentration of cortisol on the 1^st postoperative day was correlated with the total dose of dopamine (p = 0.006, r = 0.58) and adrenaline (p = 0.04, r = 0.47). The concentration of cortisol on the day of the surgery correlated with the lactate concentration on day 2 (p = 0.04, r = 0.45). The concentration of lactates on day 1 correlated with total dose of dopamine (p = 0.01, r = 0.54).

Conclusions

A short Synacthen test allows one to predict secretion of cortisol after cardiac surgery. Greater secretion of cortisol after cardiac surgery may be associated with a more difficult postoperative course. There was no decrease in cortisol secretion with age.

Comparing Hemodynamic Responses to Diazepam, Propofol and Etomidate During Anesthesia Induction in Patients with Left Ventricular Dysfunction Undergoing Coronary Artery Bypass Graft Surgery: a Double-blind, Randomized Clinical Trial

Background:

Anesthesia induction is often accompanied by a period of hemodynamic instability, which could be deleterious in patients with coronary artery disease (CAD) and left ventricular dysfunction undergoing coronary artery bypass graft (CABG) surgery. The aim of this study was to compare the hemodynamic responses to propofol, etomidate, and diazepam following anesthesia induction, laryngoscopy and intubation in CABG surgery patients with low ejection fraction (EF).

Methods:

A double-blind randomized, clinical study was performed on 150 patients with CAD and left ventricular dysfunction (EF≤35%) scheduled for elective CABG surgery with Cardiopulmonary bypass (CPB). Patients were randomly allocated to three groups A, B, and C. These patients received propofol, etomidate or diazepam at induction of anesthesia, respectively. Hemodynamic variables (systolic and diastolic blood pressure [SBP, DBP], mean arterial pressure [MAP] and heart rate [HR]) were measured and recorded at baseline, immediately before laryngoscopy and tracheal intubation and one and three minutes after intubation.

Result:

One minute after induction and before laryngoscopy, there was a statistically significant decrease from the baseline in SBP, DBP and MAP in all three groups, but these variables in each hemodynamic parameters in diazepam group were less than other two groups (p<0.001). Moreover, the mean HR decreased in patients receiving propofol and etomidate one minute after induction and before laryngoscopy, but did not decreased in the diazepam group (p=0.005).

Conclusion:

The present study showed that in patients undergoing CABG surgery with low EF, diazepam is more favorable in terms of hemodynamic stability compared to propofol and etomidate and this drug can be used safely for induction of anesthesia in patients with impaired ventricular function.

Relative Adrenal Insufficiency Is Associated With Prolonged Postoperative Hemodynamic Instability

BACKGROUND

We assessed the hypothesis that a significant proportion of patients undergoing cardiac surgery have postoperative relative adrenal insufficiency (RAI), and that this puts them at higher risk of persistent hemodynamic instability.

METHODS

A prospective study included 135 patients who underwent cardiac surgery using cardiopulmonary bypass between July 2006 and December 2007. Adrenal function was assessed 36 hours after surgery using a 1-μg cosyntropin (adrenocorticotropic hormone [ACTH]) stimulation test. Relative adrenal insufficiency was defined as a peak cortisol level inferior to 500 nmol/L or an increase in cortisol of less than 250 nmol/L, or both, compared with baseline. The primary endpoint was hemodynamic instability at 48 hours after surgery, defined as persistent requirement for any vasoactive drug. The secondary endpoint was long-term survival.

RESULTS

Postoperative RAI was diagnosed in 75 patients (56%). Compared with patients who showed a normal response to the ACTH stimulation test, patients with RAI had significantly higher rates of hemodynamic instability at 48 hours (40% versus 22%, p = 0.03). On multivariable analysis, adrenal response to the ACTH test was a significant independent predictor of hemodynamic instability at 48 hours after surgery (odds ratio 1.06 [95% confidence interval: 1.02 to 1.11] per 10 nmol/L cortisol decrease; p = 0.002). At a mean follow-up of 8.3 ± 2.8 years, patients without perioperative RAI had survival equivalent to that of the general population, whereas patients with RAI had lower than expected survival.

CONCLUSIONS

Postoperative RAI is common among patients undergoing cardiac surgery and is associated with an increased risk of persistent hemodynamic instability.

Steroid administration after anaesthetic induction with etomidate does not reduce in-hospital mortality or cardiovascular morbidity after non-cardiac surgery

BACKGROUND

We tested the primary hypothesis that corticosteroid administration after etomidate exposure reduces a composite of in-hospital mortality and cardiovascular morbidity after non-cardiac surgery.

METHODS

We evaluated ASA physical status III and IV patients who had non-cardiac surgery with general anaesthesia at the Cleveland Clinic. Amongst 4275 patients in whom anaesthesia was induced with etomidate, 804 were also given steroid intraoperatively, mostly dexamethasone at a median dose of 6 mg. We successfully matched 582 steroid patients with 1023 non-steroid patients. The matched groups were compared on composite of in-hospital mortality and cardiovascular morbidity using a generalized-estimating-equation model. Secondly, the matched groups were compared on length of hospital stay using a Cox proportional hazard model, and were descriptively compared on intraoperative blood pressures using a standardized difference.

RESULTS

There was no significant association between intraoperative steroid administration after anaesthetic induction with etomidate and the composite of in-hospital mortality or cardiovascular morbidity; the estimated common odds ratio across the two components of the composite was 0.86 [95% confidence interval (CI): 0.64, 1.16] for steroid vs non-steroid, P=0.33. The duration of postoperative hospitalisation was significantly shorter amongst steroid patients [median (Q1, Q3): 6 (3, 10) days] than non-steroid patients [7 (4, 11) days], with an estimated hazard ratio of 0.89 (0.80, 0.98) for steroid vs non-steroid, P=0.01. Intraoperative blood pressures were similar in steroid and non-steroid patients.

CONCLUSIONS

Steroid administration after induction of anaesthesia with etomidate did not reduce mortality or cardiovascular morbidity.

A randomized clinical trial comparing hemodynamic responses to ketamine-propofol combination (ketofol) versus etomidate during anesthesia induction in patients with left ventricular dysfunction undergoing coronary artery bypass graft surgery

INTRODUCTION

Anesthesia induction is often accompanied by a period of hemodynamic instability, which could be a significant problem in patients with compromised ventricular function. The aim of this study is to compare the hemodynamic responses to etomidate versus a combination of ketamine and propofol (ketofol) for anesthetic induction in patients with left ventricular dysfunction undergoing coronary artery bypass graft (CABG) surgery.

MATERIAL AND METHODS

In a double-blind randomized clinical study, a total of 84 patients with ischemic left ventricular dysfunction (EF < 40%) were randomly assigned to two groups (A and B). Patients in group A received etomidate 0.2 mg/kg and a placebo (normal saline); group B received a combination of ketamine (1 mg/kg) and propofol (1.5 mg/kg) at the induction of anesthesia. Two minutes after induction, hemodynamic variables, including systolic, diastolic, mean arterial pressure (SAP, DAP, MAP) and heart rate (HR), were measured immediately before and after the laryngoscopy, and before intubation and post-intubation at 1, 2, and 3 min.

RESULTS

The decrease in all hemodynamic parameters (SBP, DBP, MAP and HR) from induction time to laryngoscopy was greater in the ketofol group (group B) than in the etomidate group (group A) (p < 0.05). The ephedrine prescription rate due to hemodynamic changes was 24.4% (10 patients) and 5% (2 patients) in group B and group A, respectively (p = 0.03).

CONCLUSIONS

We found that etomidate provides superior hemodynamic stability as compared to ketofol in patients with left ventricular dysfunction undergoing CABG surgery under general anesthesia.

Effect of Vitamin C on adrenal suppression by etomidate induction in patients undergoing cardiac surgery: A randomized controlled trial

Introduction:

Etomidate is usually preferred in the induction of cardiac compromised patients due to its relative cardiovascular stability. However, the use of this drug has been limited as etomidate induces suppression of cortisol biosynthesis as a result of blockade of 11-beta-hydroxylation in the adrenal gland, mediated by the imidazole radical of etomidate. This study was carried out to observe the effect of Vitamin C on adrenal suppression after etomidate induction in patients undergoing cardiac surgery.

Materials and Methods:

A total of 78 patients were randomly distributed into two groups. Group-I received oral Vitamin C (500 mg) twice daily and Group-II received antacid tablet as placebo twice daily instead of Vitamin C for 7 consecutive days prior to surgery till morning of surgery. Patients of both the groups induced with etomidate (0.1–0.3 mg/kg). Blood cortisol was estimated at different points of time till 24^th postinduction hour/blood lactate, glucose, hemodynamic parameters, and perioperative outcomes were assessed.

Results:

Data of seventy patients (n = 35 in each group) were finally analyzed. Cortisol level is statistically significantly higher in Group-I (69.51 ± 7.65) as compared to Group-II (27.74 ± 4.72) (P < 0.05) in the 1^st postinduction hour. In Group-II, cortisol was consistently lower for 1^st 24 postinduction hour. Total adrenaline requirement was statistically significantly high in Group-II. Time of extubation, length of Intensive Care Unit stay arrhythmia was similar in both the groups.

Conclusion:

Vitamin C effectively inhibits etomidate-induced adrenal suppression in cardiac patients, thereby etomidate can be used as a safe alternative for induction in cardiac surgery under cardiopulmonary bypass when pretreated with Vitamin C.

Hemodynamic responses to etomidate versus ketamine-thiopental sodium combination for anesthetic induction in coronary artery bypass graft surgery patients with low ejection fraction: a double-blind, randomized, clinical trial

BACKGROUND

During induction of anesthesia and intubation, hemodynamic changes are very important; especially in patients with coronary artery disease (CAD) and left ventricular dysfunction. A little information is available on the hemodynamic effects of a combination of ketamine-thiopental for induction of anesthesia in patients undergoing coronary artery bypass graft (CABG) surgery, with impaired ventricular function.

AIM

The aim of this study was to compare the hemodynamic responses to etomidate versus ketamine-thiopental sodium combination for anesthetic induction in CABG surgery patients with low ejection fraction (EF<45%).

MATERIALS AND METHODS

In a double blind randomized clinical trial, a total of 100 patients, scheduled for elective CABG surgery were randomly assigned into two groups. These patients received either etomidate or ketamine-thiopental sodium combination at induction of anesthesia. Hemodynamics variable were measured and recorded at baseline, immediately before and after laryngoscopy and intubation, one, two and three minutes after intubation. Also, muscle twitching incidence among patients in two groups was evaluated.

RESULTS

No significant differences between the two groups regarding the changes of hemodynamic variables including systolic and diastolic arterial blood pressure, mean arterial pressure and heart rate, were notice (p>0.05). Muscle twitching was not observed in the two groups.

CONCLUSION

Hemodynamic stability after administration of ketamine-thiopental sodium combination for induction of anesthesia in patients undergoing CABG surgery, with impaired ventricular function, supports the clinical impression that this combination is safe in CABG surgery patients with low EF.

Comparison of clinical outcome variables in patients with and without etomidate-facilitated anesthesia induction ahead of major cardiac surgery: a retrospective analysis

Introduction

It is well known that etomidate may cause adrenal insufficiency. However, the clinical relevance of adrenal suppression after a single dose of etomidate remains vague. The aim of this study was to investigate the association between the administration of a single dose of etomidate or an alternative induction regime ahead of major cardiac surgery and clinical outcome parameters associated with adrenal suppression and onset of sepsis.

Methods

The anesthesia and intensive care unit (ICU) records from patients undergoing cardiac surgery over five consecutive years (2008 to 2012) were retrospectively analyzed. The focus of the analysis was on clinical parameters like mortality, ventilation hours, renal failure, and sepsis-linked serum parameters. Multivariate analysis and Cox regression were applied to derive the results.

Results

In total, 3,054 patient records were analyzed. A group of 1,775 (58%) patients received a single dose of etomidate; 1,279 (42%) patients did not receive etomidate at any time. There was no difference in distribution of age, American Society of Anesthesiologists physical score, duration of surgery, and Acute Physiology and Chronic Health Evaluation II score. Postoperative data showed no significant differences between the two groups in regard to mortality (6.8% versus 6.4%), mean of mechanical ventilation hours (21.2 versus 19.7), days in the ICU (2.6 versus 2.5), hospital days (18.7 versus 17.4), sepsis-associated parameters, Sequential Organ Failure Assessment score, and incidence of renal failure. Administration of etomidate showed no significant influence (P = 0.6) on hospital mortality in the multivariate Cox analysis.

Conclusions

This study found no evidence for differences in key clinical outcome parameters based on anesthesia induction with or without administration of a single dose of etomidate. In consequence, etomidate might remain an acceptable option for single-dose anesthesia induction.

Etomidate use and postoperative outcomes among cardiac surgery patients

BACKGROUND

Although a single dose of etomidate can cause relative adrenal insufficiency, the impact of etomidate exposure on postoperative outcomes is unknown. The objective of this study was to examine the association between a single induction dose of etomidate and clinically important postoperative outcomes after cardiac surgery.

METHODS

The authors retrospectively examined the association between etomidate exposure during induction of anesthesia and postoperative outcomes in patients undergoing cardiac surgery from January 2007 to December 2009 by using multivariate logistic regression analyses and Cox proportional hazards regression analyses. Postoperative outcomes of interest were severe hypotension, mechanical ventilation hours, hospital length of stay, and in-hospital mortality.

RESULTS

Sixty-two percent of 3,127 patients received etomidate. Etomidate recipients had a higher incidence of preoperative congestive heart failure (23.0 vs. 18.3%; P = 0.002) and a lower incidence of preoperative cardiogenic shock (1.3 vs. 4.0%; P < 0.001). The adjusted odds ratio for severe hypotension and in-hospital mortality associated with receiving etomidate was 0.80 (95% CI, 0.58-1.09) and 0.75 (95% CI, 0.45-1.24), respectively, and the adjusted hazard ratio for time to mechanical ventilation removal and time to hospital discharge was 1.10 (95% CI, 1.00-1.21) and 1.07 (95% CI, 0.97-1.18), respectively. Propensity score analysis did not change the association between etomidate use and postoperative outcomes.

CONCLUSIONS

In this study, there was no evidence to suggest that etomidate exposure was associated with severe hypotension, longer mechanical ventilation hours, longer length of hospital stay, or in-hospital mortality. Etomidate should remain an option for induction of anesthesia in cardiac surgery patients.

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.

Steroidogenesis in the adrenal dysfunction of critical illness: impact of etomidate

Introduction

This study was aimed at characterizing basal and adrenocorticotropic hormone (ACTH)-induced steroidogenesis in sepsis and nonsepsis patients with a suspicion of critical illness-related corticosteroid insufficiency (CIRCI), taking the use of etomidate-inhibiting 11β-hydroxylase into account.

Method

This was a prospective study in a mixed surgical/medical intensive care unit (ICU) of a university hospital. The patients were 62 critically ill patients with a clinical suspicion of CIRCI. The patients underwent a 250-μg ACTH test (n = 67). ACTH, adrenal steroids, substrates, and precursors (modified tandem mass spectrometry) also were measured. Clinical characteristics including use of etomidate to facilitate intubation (n = 14 within 72 hours of ACTH testing) were recorded.

Results

At the time of ACTH testing, patients had septic (n = 43) or nonseptic critical illness (n = 24). Baseline cortisol directly related to sepsis and endogenous ACTH, independent of etomidate use. Etomidate was associated with a lower baseline cortisol and cortisol/11β-deoxycortisol ratio as well as higher 11β-deoxycortisol, reflecting greater 11β-hydroxylase inhibition in nonsepsis than in sepsis. Cortisol increases < 250 mM in exogenous ACTH were associated with relatively low baseline (HDL-) cholesterol, and high endogenous ACTH with low cortisol/ACTH ratio, independent of etomidate. Although cortisol increases with exogenous ACTH, levels were lower in sepsis than in nonsepsis patients, and etomidate was associated with diminished increases in cortisol with exogenous ACTH, so that its use increased, albeit nonsignificantly, low cortisol increases to exogenous ACTH from 38% to 57%, in both conditions.

Conclusions

A single dose of etomidate may attenuate stimulated more than basal cortisol synthesis. However, it may only partly contribute, particularly in the stressed sepsis patient, to the adrenal dysfunction of CIRCI, in addition to substrate deficiency.

Corticosteroids for severe sepsis: an evidence-based guide for physicians

Septic shock is characterized by uncontrolled systemic inflammation that contributes to the progression of organ failures and eventually death. There is now ample evidence that the inability of the host to mount an appropriate hypothalamic-pituitary and adrenal axis response plays a major in overwhelming systemic inflammation during infections. Proinflammatory mediators released in the inflamed sites oppose to the anti-inflammatory response, an effect that may be reversed by exogenous corticosteroids. With sepsis, via nongenomic and genomic effects, corticosteroids restore cardiovascular homeostasis, terminate systemic and tissue inflammation, restore organ function, and prevent death. These effects of corticosteroids have been consistently found in animal studies and in most recent frequentist and Bayesian meta-analyses. Corticosteroids should be initiated only in patients with sepsis who require 0.5 μg/kg per minute or more of norepinephrine and should be continued for 5 to 7 days except in patients with poor hemodynamic response after 2 days of corticosteroids and with a cortisol increment of more than 250 nmol/L after a standard adrenocorticotropin hormone (ACTH) test. Hydrocortisone should be given at a daily dose of 200 mg and preferably combined to enteral fludrocortisone at a dose of 50 μg. Blood glucose levels should be kept below 150 mg/dL.