From the Guidelines
Neostigmine is indicated for the treatment of postoperative ileus, specifically for acute colonic pseudo-obstruction (Ogilvie's syndrome), when conservative management fails 1.
Key Considerations
- The recommended dose is typically 2.5 mg administered intravenously over 3-5 minutes, which can be repeated in 3 hours if no response is observed, up to a maximum of 3 doses in 24 hours.
- Prevention of postoperative ileus is a key objective in the recovery process, and a multimodal approach to optimize gut function is recommended, including measures such as gum chewing and oral magnesium 1.
- Caution should be exercised in patients with certain medical conditions, such as asthma, bradycardia, or hypotension, and in those taking medications that may interact with neostigmine, such as beta-blockers or anticholinesterases.
- It is essential to monitor patients closely for potential side effects, including abdominal cramps, diarrhea, and bronchospasm.
Prevention Strategies
- Minimally invasive surgery, optimized fluid management, and opioid-sparing analgesia are key strategies to prevent postoperative ileus 1.
- Early mobilization, early postoperative food intake, and laxatives may also be beneficial in preventing postoperative ileus 1.
- Omission of postoperative nasogastric tubes is recommended to prevent postoperative ileus 1.
From the Research
Indications for Neostigmine in Postoperative Ileus
- Neostigmine is indicated for the treatment of postoperative ileus, acute colonic pseudo-obstruction (ACPO), and refractory constipation 2, 3, 4, 5.
- The medication can be administered intravenously or subcutaneously, with the subcutaneous route being a viable alternative to intravenous administration 2.
- Neostigmine enhances excitatory parasympathetic activity, competing with acetylcholine for attachment to acetylcholinesterase, and enhancing cholinergic action, which helps restore peristalsis in patients with ACPO 4.
Contraindications and Precautions
- Neostigmine should be avoided in patients with new-onset heart block, a history of second-degree heart block, or following bowel resection with primary anastomosis 2.
- Patients with symptomatic first-degree heart block or those with a permanent pacemaker should be treated with caution 6.
- Monitoring for bradycardia with telemetry may be considered due to the potential for adverse cardiac effects 2, 6.
Efficacy and Safety
- Neostigmine has been shown to be safe and effective in treating ACPO, with complete clinical resolution of large bowel distention occurring in approximately 90% of patients 4.
- The median time to pass flatus after administration of neostigmine can range from 30 seconds to 10 minutes 4.
- Adverse effects, such as abdominal pain, cramping, and bradycardia, can occur, but are generally infrequent and manageable 3, 4.