Your browser is no longer supported

For the best possible experience using our website we recommend you upgrade to a newer version or another browser.

Your browser appears to have cookies disabled. For the best experience of this website, please enable cookies in your browser

We'll assume we have your consent to use cookies, for example so you won't need to log in each time you visit our site.
Learn more


Safe removal of knotted nasogastric tubes

  • 1 Comment

Knotting or looping of nasogastric tubes when in situ can distress the patient on removal. Nurses should know how to recognise and respond to the situation


This article discusses how looping or knotting while in situ can occur, and reports a case study of such an incident. It also presents a mnemonic to help health professionals to remember how to respond if a tube becomes knotted.

Citation: Wright S et al (2014) Safe removal of knotted nasogastric tubes. Nursing Times; 110: 43, 16-17.

Authors: Steve Wright is lead specialist practitioner; Janindra Warusavitarne is consultant colorectal surgeon; Irshad Shaikh is senior resident surgical officer; all at St Mark’s Hospital, North West London Hospitals Trust.


Nasogastric tubes are used in a range of clinical situations. In postoperative surgical patients they are usually inserted for the following reasons:

  • To decompress the stomach of its contents, usually after abdominal surgery;
  • To provide enteral feeding;
  • To administer liquid medication (Makama, 2010).

Nasogastric tubes come in a variety of sizes 8, 10, 12, 14, 16, and 18 French gauge (usually abbreviated as Ch after its inventor, Charriere, or Fr). This is the same system used to measure urinary catheters. Ryles tubes, used to decompress the stomach, are usually a wider bore 12-18Ch, while enteral feeding tubes are usually a fine-bore size 8-10Ch, although smaller bore tubes are available for paediatric or neonatal patients.

This article focuses on NG tubes used to drain the stomach of surgical patients experiencing transient impairment of intestinal motility following abdominal surgery, known as postoperative ileus (Hans-Geurts et al, 2007). Box 1 lists its signs and symptoms.

Box 1. Symptoms of postoperative ileus

  • Abdominal distension 
  • Abdominal pain
  • Delayed passage of flatus/stool
  • Inability to eat
  • Nausea
  • Vomiting

Source: Barletta and Senagore (2014)

Risks and complications

In recent years, much attention has been placed on the importance of ensuring NG tubes are correctly placed to avoid serious complications or death; misplaced NG tubes are one of 25 never events for the NHS (NHS England, 2013). The National Patient Safety Agency issued an alert to facilitate the safe insertion of NG feeding tubes, advising healthcare providers to implement a range of policies and procedures to minimise the risk of incorrect tube placement, including staff training, competency frameworks and supervision to ensure all health professionals involved with NG tube placement checks have been assessed as competent (NPSA, 2011).

Reported complication rates for insertion of NG tubes varies widely, with figures of 0.3-15% quoted in the literature (Smith et al, 2012). A number of complications can occur during insertion of an NG tube:

  • The tube may coil in the patient’s throat;
  • Epistaxis (nosebleed);
  • The tube may enter the lungs.

Other problems that occur much less frequently but nurses should be aware of are:

  • Aspiration;
  • Perforation of the oesophagus;
  • Parotitis;
  • Sinusitis;
  • The tube entering the brain;
  • Death from feed entering the lung (Durai et al, 2009).

Although the nursing literature places much emphasis on the correct and safe insertion of NG tubes to minimise the risk of complications (Dougherty and Lister, 2011), there is little information and no clear guidance on the safe removal of NG tubes in clinical practice; the task is often seen as a simple procedure and delegated to junior members of the nursing team. However, a number of complications can occur when removing an NG tube:

  • Respiratory distress (Agrawal et al, 2002);
  • Laryngeal injury( Malik et al, 1999);
  • Epistaxis.

Knotted tube

Tube removal complications can be caused by knotting or twisting of the tube. Knots are usually simple (Fig 1), or lariat loop (Fig 2); they occur when the tube tip passes through a coil of excess length of tube (Kinshuck et al, 2011), and the majority occur in fine-bore tubes (Trujillo, 2006). The removal process may cause the knot to tighten, making removal difficult and distressing for the patient.

Factors contributing to knotting of NG tubes include:

  • Narrow bore of tube;
  • Altered anatomy (for example a small stomach following gastrectomy);
  • Multiple manipulations of the tube;
  • Inserting the tube too far into the stomach;
  • Spontaneous knotting due to neck movement or coughing;
  • Softening of the tube at body temperature (Santhanam and Margarson, 2008).

Removing nasogastric tubes

Removal of NG tubes should be undertaken with a slow, controlled withdrawal rather than a rapid, uncontrolled motion. This allows the procedure to be stopped if resistance is encountered (Dinsmore and Benson, 1999). If there is any resistance removal should stop immediately and the oral cavity should be assessed for a knot or lariat loop. If either is discovered the procedure should be discontinued and the patient reassured. The patient should then be reviewed immediately by a doctor for endoscopic removal (Tapiawala et al, 2008).

Case study

The case study in Box 2 describes an NG tube removal complicated by a knotted tube in a postoperative surgical patient in our trust. This was an important incident for the surgical and nursing team caring for Mr Wells to reflect on and learn from. Before this event, nurses on the ward were unaware of this unusual complication that can occur during NG tube removal. Though knots and lariat loops in these tubes are a rare occurrence, the team’s practice has changed.

Box 2. case study

John Wells* was admitted to the ward following an emergency laparoscopic appendicectomy for a perforated appendix. On the second day postoperatively Mr Wells was not progressing as expected, and he exhibited signs of postoperative paralytic ileus.

The surgical team decided to insert a Ryles NG tube, which initially drained 1,250ml of bile. Over the following days the tube drainage diminished and the team felt the tube could be removed.

The nursing staff who tried to remove the tube at the bedside were unaware of the potential complication of knotting in the tube. Mr Wells became distressed and agitated when the tube could not be removed, and when a torch was used to visualise his oral cavity a knot was clearly visible in his mouth, although no trauma had been caused by the nurses trying to remove the tube. The surgical team were called and Mr Wells was taken to the endoscopy department where the tube was safely removed under sedation.

Further examination demonstrated no injury or damage to the oesophagus. Mr Wells made a full recovery, and was discharged home two days later. *

The patient’s name has been changed

“SAVES” mnemonic

On reviewing the available literature on complications relating to safe NG tube removal, no aide-memoire or similar mnemonic could be found. We felt that this would be useful for nursing staff, to help the safe removal of NG tubes when resistance is felt, and devised the mnemonic SAVES. This has been adopted within our area of clinical practice to facilitate the safe removal of NG tubes:

S - Stop immediately if resistance is felt;

A - Ask patient to open their mouth;

V - Visualise oral cavity;

E - Evaluate what you see - knot or lariat in the NG tube?

S - Summon help from a doctor to facilitate safe removal.

By using this mnemonic when contemplating removal of NG tubes nurses can ensure that if a problem arises it can be dealt with safely and effectively. 

Key points

  • Nasogastric tubes are used in a range of clinical situations, and are associated with a range of complications
  • Misplacement of nasogastric tubes is considered to be a “never event” within the NHS in England
  • Nursing literature offers little guidance on the safe removal of nasogastric tubes
  • Knotting or looping while in situ is an unusual complication associated with nasogastric tubes
  • Nurses caring for patients with nasogastric tubes should be aware of how to recognise and respond to knotted tubes
  • 1 Comment

Readers' comments (1)

Have your say

You must sign in to make a comment

Please remember that the submission of any material is governed by our Terms and Conditions and by submitting material you confirm your agreement to these Terms and Conditions. Links may be included in your comments but HTML is not permitted.