From the Guidelines
Metoclopramide is the recommended prokinetic agent for a dilated colon, despite its potential for serious adverse effects, due to its FDA approval for the treatment of gastroparesis and its ability to enhance gastric emptying and intestinal transit. The typical adult dosage is 10 mg orally or intravenously three to four times daily, with treatment duration typically ranging from a few days to weeks depending on clinical response, as noted in 1. Metoclopramide works by blocking dopamine receptors in the gastrointestinal tract, which enhances gastric emptying and intestinal transit by increasing the tone and amplitude of gastric contractions and relaxing the pyloric sphincter.
For patients with severe colonic dilation, such as in acute colonic pseudo-obstruction (Ogilvie's syndrome), neostigmine may be considered as an alternative at a dose of 2-2.5 mg intravenously over 3-5 minutes under cardiac monitoring, as mentioned in 1. Side effects of metoclopramide include extrapyramidal symptoms, drowsiness, and restlessness, so it should be used cautiously in elderly patients and those with Parkinson's disease.
Other treatment options include domperidone, erythromycin, and prucalopride, but their use may be limited by potential side effects or lack of availability, as discussed in 1 and 1. Treatment should be accompanied by other supportive measures such as:
- Correction of electrolyte abnormalities
- Discontinuation of anticholinergic medications
- Appropriate bowel management It's essential to weigh the benefits and risks of each prokinetic agent and consider the individual patient's needs and medical history when making a treatment decision, as emphasized in 1 and 1.
From the Research
Prokinetic Agents for Dilated Colon
- The use of prokinetic agents for a dilated colon is supported by several studies, including a case report where a patient with methamphetamine-induced ileus was treated with intravenous metoclopramide and erythromycin 2.
- Erythromycin has been shown to be effective in facilitating gastric emptying and tolerance to intragastric nutrition in critically ill patients, and may be more effective than metoclopramide for enhancing gastric motility 3.
- In patients with terminal illness, erythromycin suspension has been used successfully in preventing recurrence of small bowel obstruction, and may be a viable alternative to metoclopramide and domperidone 4.
- However, the use of erythromycin-based prokinetic therapy has been associated with a risk of diarrhoea in critically ill patients, although this is not typically related to Clostridium difficile infection 5.
- Metoclopramide and erythromycin are currently the most promising prokinetic agents for treating motility disorders in critically ill patients, although novel propulsive agents such as motilin agonists and mu-receptor antagonists are being developed 6.