Choosing a Prokinetic for Your Patient Beyond Metoclopramide

2023 update on the clinical management of gastroparesis

INTRODUCTION

Gastroparesis is characterized by symptoms suggesting gastric retention of food and objective evidence of delayed gastric emptying in the absence of a mechanical obstruction. Nausea, vomiting, early satiety, and postprandial fullness are the classic symptoms of gastroparesis. Gastroparesis is increasingly encountered by physicians. There are several recognized etiologies of gastroparesis, including diabetic, post-surgical, medication-induced, post-viral, and idiopathic.

AREAS COVERED

A comprehensive literature review was conducted to identify studies discussing gastroparesis management. Dietary modifications, medication adjustments, glucose control, antiemetic agents, and prokinetic agents are all part of gastroparesis management. In this manuscript, we detail treatments evolving for gastroparesis, including nutritional, pharmaceutical, device, and recent advanced endoscopic and surgical therapies. This manuscript concludes with a speculative viewpoint on how the field will evolve in 5 years' time.

EXPERT OPINION

Identification of the dominant symptoms (fullness, nausea, abdominal pain, and heartburn) helps to direct management efforts of the patients. Treatments for refractory (treatment resistant) symptoms may include gastric electric stimulation and intra-pyloric interventions like botulinum toxin and endoscopic pyloromyotomy. Understanding the pathophysiology of gastroparesis, relating pathophysiologic abnormalities to specific symptoms, new efficacious pharmacotherapies, and better understanding of the clinical predictors of response of therapies, are priorities for future research in the field of gastroparesis.

Prokinetic Agents

Gastrointestinal (GI) prokinetic agents are drugs that increase GI motility and promote the movement of contents in the GI tract by amplifying and controlling the contraction of GI smooth muscle. Currently used prokinetics increase GI motility by acting as a dopamine D₂ receptor antagonist (e.g., metoclopramide, domperidone, levosulpiride) and 5-HT₄ receptor agonist (e.g., mosapride, prucalopride). Some prokinetics also have a cholinesterase inhibitory property (e.g., itopride), and herb-derived prokinetics (e.g., motilitone) affect multiple receptors. Depending on the type and distribution of receptors on which the prokinetics bind, the effect(s) may be regional or throughout the GI tract. Most prokinetics have been used for functional dyspepsia and gastroparesis because they mainly affect upper GI motility. However, prucalopride, a highly selective 5-HT₄ receptor agonist, is used primarily to treat chronic constipation and pseudo-obstruction. Dopamine D₂ receptor antagonists also inhibit the D₂ receptor in the medulla oblongata chemoreceptor trigger zone; therefore, they can treat nausea and vomiting. However, short term use of dopamine D₂ antagonists at an appropriate dose is recommended because of their potential for central nervous system side effects by penetrating the blood-brain barrier. It is necessary to know the mechanism of action, each clinical trial’s characteristics, and the side effects of prokinetics to obtain the best clinical outcomes. This article aims to summarize the results of clinical studies related to the impact of currently available prokinetic agents in Korea on GI motility.

[The Gastrointestinal Tract in Intensive Care Medicine - Overview 2020]

Gastrointestinal dysfunctions and failure are common clinical incidents in critically ill patients, which are recognized as both, primary and even more often as secondary diagnoses as consequence of an already existing disease or as a corollary of intensive care treatment. These functional complications may aggravate into life-threatening emergencies and are highly associated with prognosis and increased mortality.This article gives an overview about the pathophysiology, diagnostics and therapy of three very relevant current topics in intensive care medicine: prophylaxis and management of gastrointestinal bleeding, gastrointestinal motility and absorption disorders as well as different forms of liver dysfunctions.

Esophageal and Gastric Motility Disorders in the Elderly

The elderly are particularly prone to developing upper gastrointestinal disturbances. Changes are due to the aging process, diabetes, cardiovascular risk factors, and neurologic issues. Medications used to treat these underlying conditions can cause gastrointestinal symptoms. Dysphagia is common and can be oropharyngeal and/or esophageal. Gastroparesis is due to either medications such opiates, or due to neurologic sequala of diabetes, cerebrovascular accidents, or neurologic diseases such as Parkinson's disease. Given limitations in many commonly used prokinetics with a wide range of side effect profiles including neurologic and cardiac, the focus of treatment should be on symptom management with dietary changes.

Ultrasonographic Assessment of Metoclopramide Administration Effectiveness in Accelerating Gastric Emptying Before Urgent Surgery in Patients with Insufficient NPO Time

Background

Aspiration is one of the important complications of general anesthesia, although infrequent as well as accompanying high morbidity and mortality. The volume of gastric content is considered as a risk factor in this regard. Therefore, it is normally mostly recommend to consider proper fasting time before induction of general anesthesia.

Objectives

This study was conducted to assess the effect of metoclopramide on reducing gastric contents in patients with incomplete fasting before induction of general anesthesia.

Methods

This quasi-experimental study was conducted on patients with urgent surgical indications with incomplete NPO time. Every other patient received metoclopramide or placebo. Patients in the intervention group received 10 mg (2 ml) of intravenous metoclopramide, and patients in the control group received 2 ml of distilled water as a placebo. Patients in both groups underwent ultrasonography before starting surgery by an expert radiologist to calculate gastric antral grade (GAG) and cross-sectional antral area (CSA). These measurements were then taken for the second time 30 minutes after intervention, before starting the surgery. The values were compared statistically.

Results

The data of 60 patients were analyzed, of which 30 were in each group. The mean age, body mass index, type of the last consumed food (solid or fluid), NPO time in the two groups were not significantly different (P value > 0.05). The number of patients in the metoclopramide group with higher GAG (P value = 0.001) and the mean CSA (P value = 0.004) before the intervention was more than the control group. The GAG and mean CSA after intervention were not significantly different between the two groups; but the mean difference of decrease in CSA in the metoclopramide group was more than the control group (4.3 vs. 0.99; P value = 0.001), and changes of GAG after intervention to lower levels in the metoclopramide group was more than the control group (P value < 0.05).

Conclusions

In the current study in which ultrasonographic indexes, including GAG and CSA, were assessed as a suboptimal gastric emptying test method, it was found that metoclopramide could accelerate gastric emptying compared to placebo in patients with incomplete fasting before induction of general anesthesia.