From the Guidelines
Ileus is primarily caused by surgical manipulation, medications, and underlying medical conditions. Certain medications, such as opioid analgesics like morphine and anticholinergics like scopolamine, can slow down bowel motility and contribute to the development of ileus 1. Additionally, postoperative ileus is a common complication following abdominal surgery, with the duration of ileus typically ranging from 2-5 days, depending on the extent of surgical manipulation and individual patient factors 1.
Key Factors Contributing to Ileus
- Surgical manipulation: Abdominal surgery can cause ileus due to the manipulation of intestinal tissues, leading to inflammation and disruption of normal bowel function 1.
- Medications: Opioid analgesics and anticholinergics can slow down bowel motility, contributing to the development of ileus 1.
- Underlying medical conditions: Certain medical conditions, such as intestinal dysmotility, can increase the risk of developing ileus 1.
- Fluid management: Excess fluid administration can lead to postoperative ileus and delayed gastric emptying 1.
- Postoperative care: Early mobilization, early postoperative food intake, and omission of postoperative nasogastric tubes can help prevent postoperative ileus 1.
Prevention and Management of Ileus
Prevention and management of ileus involve a multifaceted approach, including:
- Minimally invasive surgery: Reduces the risk of postoperative ileus 1.
- Optimized fluid management: Avoids excess fluid administration and promotes early return of bowel function 1.
- Opioid-sparing analgesia: Reduces the risk of opioid-induced ileus 1.
- Early mobilization: Promotes early return of bowel function 1.
- Early postoperative food intake: Helps maintain intestinal function and reduces the risk of ileus 1.
From the FDA Drug Label
Morphine sulfate tablets are contraindicated in patients with gastrointestinal obstruction, including paralytic ileus. The morphine in morphine sulfate tablets may cause spasm of the sphincter of Oddi. Opioids may cause increases in serum amylase Monitor patients with biliary tract disease, including acute pancreatitis for worsening symptoms. The concomitant use of anticholinergic drugs may increase risk of urinary retention and/or severe constipation, which may lead to paralytic ileus
The cause of ileus is not directly stated in the label, but it is mentioned that morphine sulfate tablets are contraindicated in patients with gastrointestinal obstruction, including paralytic ileus, and that anticholinergic drugs may increase the risk of urinary retention and/or severe constipation, which may lead to paralytic ileus. Therefore, it can be inferred that opioids, such as morphine, and anticholinergic drugs may contribute to the development of ileus. 2 2
From the Research
Causes of Ileus
The causes of ileus are multifactorial and can be attributed to various factors, including:
- Neurogenic components, such as surgical stress and prolonged opioid analgesic use 3
- Inflammatory components, such as gastrointestinal stretch and inflammation 4
- Hormonal components, which can be affected by surgical stress and other factors 3
- Pharmacologic components, such as the use of opioids and other medications 3, 4
Risk Factors for Postoperative Ileus
Several risk factors have been identified for postoperative ileus, including:
- Duration of surgery over 200 minutes 5
- Opiate consumption over 10 mg on the second postoperative day 5
- Carcinoma situated in the transverse colon 5
- Fluid overload, exogenous opioids, neurohormonal dysfunction, gastrointestinal stretch, and inflammation 4
Pathophysiology of Ileus
The pathophysiology of ileus is complex and not fully understood, but it is thought to involve a combination of neurogenic, inflammatory, hormonal, and pharmacologic mechanisms 3, 4, 6. The development of ileus can lead to a range of complications, including delayed surgical wound healing, atelectasis, pneumonia, and deep vein thrombosis 3.
Prevention and Management of Ileus
Prevention and management of ileus are crucial to reducing its clinical and economic impact. Strategies such as minimally invasive surgery, protocol-driven recovery, and measures to avoid major inflammatory events may help reduce the incidence of ileus 6. Early enteral nutrition (EEN) has been shown to facilitate the return of normal bowel function and reduce hospital length of stay 4. However, the effectiveness of other interventions, such as metoclopramide and erythromycin, is uncertain 4.