The laboratory response to glucagon dosages used in gastrointestinal examinations

The acute effect of glucagon on components of energy balance and glucose homoeostasis in adults without diabetes: a systematic review and meta-analysis

Objective

Using a systematic review and meta-analysis, we aimed to estimate the mean effect of acute glucagon administration on components of energy balance and glucose homoeostasis in adults without diabetes.

Methods

CENTRAL, CINAHL, Embase, MEDLINE, PubMed, and Scopus databases were searched from inception to May 2021. To be included, papers had to be a randomised, crossover, single- or double-blind study, measuring ad libitum meal energy intake, energy expenditure, subjective appetite, glucose, and/or insulin following acute administration of glucagon and an appropriate comparator in adults without diabetes. Risk of bias was assessed using the Revised Cochrane Risk of Bias Tool for Randomized trials with additional considerations for cross-over trials. Certainty of evidence was assessed using the GRADE approach. Random-effect meta-analyses were performed for outcomes with at least five studies. This study is registered on PROSPERO (CRD42021269623).

Results

In total, 13 papers (15 studies) were considered eligible: energy intake (5 studies, 77 participants); energy expenditure (5 studies, 59 participants); subjective appetite (3 studies, 39 participants); glucose (13 studies, 159 participants); insulin (12 studies, 147 participants). All studies had some concerns with regards to risk of bias. Mean intervention effect of acute glucagon administration on energy intake was small (standardised mean difference [SMD]: –0.19; 95% CI, –0.59 to 0.21; P = 0.345). Mean intervention effect of acute glucagon administration on energy expenditure (SMD: 0.72; 95% CI, 0.37–1.08; P < 0.001), glucose (SMD: 1.11; 95% CI, 0.60–1.62; P < 0.001), and insulin (SMD: 1.33; 95% CI, 0.88–1.77; P < 0.001) was moderate to large.

Conclusions

Acute glucagon administration produces substantial increases in energy expenditure, and in circulating insulin and glucose concentrations. However, the effect of acute glucagon administration on energy intake is unclear. Insufficient evidence was available to evaluate the acute effect of glucagon on subjective appetite.

Pharmacological and mechanical management of calcium channel blocker toxicity

Cardiovascular instability associated with calcium channel blocker toxicity comprises a small percentage of overdose presentations, yet they are associated with a high mortality rate. We detail the management of a 64-year-old man who took an intentional overdose of 840 mg nimodipine. We include the treatment he received and highlight the scarcity of evidence behind the use of gastric decontamination, calcium, glucagon, intravenous lipid emulsion, high-dose insulin therapy, sodium bicarbonate, vasopressors and methylene blue in calcium channel blocker toxicity. Additionally, the article explores the use of electrical pacing and venoarterial extracorporeal membrane oxygenation (VA-ECMO). Following successful weaning of VA-ECMO, the patient was successfully extubated but remained neurologically impaired due to hypoxic-ischaemic brain injury, critical care polyneuropathy and renal failure requiring dialysis. He has cerebral performance category 3; he has mild cognitive impairment but able to perform some activities of daily living independently and communicate his thoughts and needs. He requires no respiratory or cardiovascular support.

Contrast media for fluoroscopic examinations of the GI and GU tracts: current challenges and recommendations

One of the significant challenges facing radiologists who perform and interpret studies of the gastrointestinal and genitourinary systems have been periodic interruptions in the availability of barium and iodinated contrast media specially formulated for gastrointestinal (GI) and genitourinary (GU) studies. These interruptions are due to the US Food and Drug Administration's recent requirement for more stringent documentation of the safety and efficacy of contrast media and the consolidation among contrast manufacturers. Therefore, radiologists may be required to recommend an alternative means of evaluation, such as computed tomography, magnetic resonance, or endoscopy, or they may need to substitute a different formulation of a contrast agent not specifically developed for GI or GU use, for example the utilization of an agent designed and marketed for vascular use. This article reviews the current status of fluoroscopic contrast media, and provides suggestions and recommendations for the optimal and alternative use of contrast media formulations.

Management of beta-adrenergic blocker and calcium channel antagonist toxicity

State-of-the-art therapy for beta-adrenergic receptor blocker and calcium channel antagonist toxicity is reviewed in the light of new insights into drug-induced shock. A brief discussion of pathophysiology, including cardiac, hemodynamic, and metabolic effects of cardiac drug toxicity, provides a foundation for understanding the basis of therapy. The major focus of this review is a critical evaluation of antidotal use of calcium, glucagon, catecholamines, insulin-euglycemia, and other novel therapies based on investigational studies and cumulative clinical experience.

A randomized study comparing glucagon and hyoscine N-butyl bromide before endoscopic retrograde cholangiopancreatography

BACKGROUND

This study tried to resolve whether glucagon is a better premedication for endoscopic retrograde cholangiopancreatography (ERCP).

METHODS

We first measured the basal blood sugar and amylase levels. Then an endoscope was placed in the duodenum without premedication, and basal pulse and duodenal peristaltic rates were measured. ERCP began after studied subjects were randomly premedicated with either 1 mg glucagon (n = 38) or 40 mg hyoscine N-butyl bromide (n = 36) intravenously. Ten minutes later the variables were measured again.

RESULTS

Glucagon elicited hyperglycemia whereas hyoscine N-butyl bromide manifested an anticholinergic effect. No difference was found between these two groups with regard to the necessary interval for ERCP (20.6 +/- 14.1 min versus 21.4 +/- 14.7 min; NS) or the success rate for cholangiopancreatography (92.1% versus 91.7%; NS). Neither hyperamylasemia nor pancreatitis was preventable when glucagon was used.

CONCLUSIONS

The two premedications appear equally effective in the performance of ERCP.

Utility of glucagon in the emergency department

Glucagon is a pancreatic polypeptide hormone that has diverse utility as both a therapeutic and diagnostic agent. Many of its pharmacologic actions are pertinent to the practice of emergency medicine. The author reviews the literature supporting each potential use of the drug and the purported physiologic mechanisms by which glucagon exerts these actions. The indications and proper dosages for glucagon in the acute care setting are summarized.