A knotted nasogastric tube.

Sir,

Nasogastric tubes are widely used in the practice of anesthesiology and can cause considerable morbidity and, also, mortality.[1] Previous case reports on nasogastric tube knotting have usually involved nasogastric tubes that were in situ for a prolonged duration, ranging from 1[2] to 12 days.[3] We report a knotted nasogastric tube causing difficulty in removal of the tube during a surgical procedure that lasted 40 min and wish to highlight the fact that nasogastric tube knotting is not essentially associated with prolonged duration of intubation.

A 45-year-old, obese (body mass index, 31.1 kg/m2 ) lady, ASA physical status 1, was posted for laparoscopic cholecystectomy. Intraoperatively, after tracheal intubation, a 16 F nasogastric tube (Romsons TM, Nunhai, Agra, India) was inserted through the right nostril. It was fixed at an approximately 55 cm mark at the nostril after confirmation of correct placement by aspiration of gastric contents. After creation of pneumoperitoneum, the surgeon pointed out that the stomach was still distended. The anesthesia trainee then performed direct laryngoscopy and reinserted the nasogastric tube with the aid of a Magill's forceps.

Postoperatively, attempts to withdraw the nasogastric beyond the 60 cm mark were met with resistance. After two such failed attempts, direct laryngoscopy was performed, which, to our surprise, revealed the presence of a knot at the distal end of the nasogastric tube, which was now lying in the nasopharynx [Figure 1].

Figure 1

Knotted nasogastric tube

The knotted end of the tube was withdrawn from the mouth with the aid of a Magill's forceps to an approximate length of 10 cm and cut, while the remaining length of the tube was removed easily through the nose. The tracheal extubation was uneventful and the patient was discharged from the hospital on the second postoperative day in a satisfactory condition.

Nasogastric tube coiling and knotting is more common with small bore tubes or in patients with small stomachs.[4] Insertions of an extra length of the nasogastric tube, endotracheal intubation and repetitive advancement of the tube are the other risk factors associated with knotting of the tube. Agarwal et al. state that pushing or pulling of the nasogastric tube after it has been placed, either by an operator or due to coughing or neck movement, may lead to the formation of a loop.[5] Hence, repositioning of the nasogastric tube should be avoided, especially in patients who are anesthetized or have an obtunded cough reflex. It is imperative to measure the correct length of insertion of the nasogastric tube prior to its placement and mark this length with a marker or tape so that only the necessary length of the tube is inserted and any unrecognized tube movement can be detected. A lateral radiograph of the head and neck may aid in the diagnosis of a coiled and knotted nasogastric tube.

There should be a low threshold for aborting attempts of nasogastric tube withdrawal if such attempts are met with resistance to avoid serious complications, including respiratory distress,[5] or laryngeal injury and epistaxis.[6]