What happens to Small Bowel Obstruction (SBO) when Nasogastric (NG) suction is stopped?

From the Guidelines

When nasogastric (NG) tube suction is stopped in a patient with small bowel obstruction (SBO), it is crucial to closely monitor for signs of worsening obstruction or complications, as the cessation of decompression can lead to increased abdominal distension, nausea, vomiting, and potentially life-threatening complications such as bowel ischemia or perforation 1.

Physiological Changes

Without the decompression provided by the NG tube, several physiological changes occur:

• Increase in abdominal distension due to accumulation of intestinal secretions and gas in the obstructed bowel
• Worsening of abdominal pain and discomfort
• Potential increase in pressure within the bowel lumen, which can worsen the obstruction and increase the risk of complications
• Fluid and electrolyte imbalances may worsen as the body continues to secrete fluids into the obstructed bowel without the removal provided by suction
• Risk of bacterial overgrowth in the stagnant intestinal contents, potentially leading to bacterial translocation and sepsis

Clinical Considerations

It is essential to consider the following:

• NG suction should only be discontinued when there are clear signs of resolving obstruction, such as decreased NG output, passage of flatus or stool, or improved radiographic findings 1
• Close monitoring is crucial for patients with SBO after NG suction is stopped to promptly identify any signs of worsening obstruction or complications
• The use of water-soluble contrast administration has been shown to be a valid and safe treatment that correlates with a significant reduction in the need for surgery in patients with adhesive small bowel obstruction, and may be considered in the management of these patients 1

From the Research

Effects of Stopping Nasogastric Suction on SBO

• When nasogastric (NG) suction is stopped in patients with small bowel obstruction (SBO), the effects on the patient's condition can vary depending on the individual case and the severity of the obstruction 2.
• Studies have shown that the use of nasogastric tubes (NGTs) in patients with SBO can be associated with increased risks of pneumonia and respiratory failure, as well as longer hospital stays and time to resolution of the obstruction 2.
• However, NG suction can be beneficial in patients with significant distension and vomiting, as it can help remove contents proximal to the site of obstruction and alleviate symptoms 3.
• The decision to stop NG suction should be made on a case-by-case basis, taking into account the patient's overall condition, the severity of the obstruction, and the presence of any complications such as strangulation or perforation 3, 4, 5.
• In some cases, the removal of the NGT can lead to a reduction in complications and a shorter hospital stay, as patients without active emesis may not require NG decompression 2.
• The management of SBO should be tailored to the individual patient, and a multidisciplinary approach involving clear communication and evidence-based decision making is essential for optimal outcomes 6.