Insertion of the nasogastric tube made easy.

Abstract

Gastric tube insertion in anesthetized, paralyzed, and intubated patients is routine practice during many surgical operations. Occasionally, this procedure may be difficult. Many techniques have been proposed to aid gastric tube insertion, including anterior displacement of the larynx, lateral neck pressure, use of endotracheal tubes split longitudinally as an introducer, and immersion of the gastric tube in ice water to harden it before use. Most anesthesiologists have developed their own technique of insertion gastric tubes, with variable success rates.Ozer and Benumof1viewed the passage of nasogastric and orogastric tubes in 60 patients via a fiberscope placed through the left naris. They found the most common sites of impaction to be the piriform sinuses and the arytenoid cartilages. They also found that lateral neck pressure converted these impactions to successful passes 85% of the time.In our experience, passage of the nasogastric or orogastric tube with the patient’s head in the lateral position (turned to either the left or the right) often results in a higher success rate than with the patient’s head in the neutral position. We find that by turning the patient’s head laterally, the path taken by the tip of the tube follows the lateral border of the pharynx, and the tube glides smoothly through the esophagus into the stomach, without coiling in the laryngopharynx. It may be that having the patient’s head turned to one side has a similar effect as applying lateral neck pressure, thus aiding the passage of the tube.We designed a randomized observational study to determine whether insertion of an nasogastric tube in the lateral position results in a higher success rate than insertion in the neutral position. We recruited 30 consecutive patients with normal airways (Mallampati 1 or 2) and normal neck movements undergoing elective surgery who required general anesthesia, intubation, and nasogastric tube insertion as part of the procedure.After obtaining informed consent from the patient, general anesthesia was induced, and the trachea was intubated after administration of an appropriate muscle relaxant. The patient was then randomized into either the neutral group or the lateral group by opening a presealed opaque envelope. A patient assigned to the neutral group had the nasogastric tube inserted with the head in the neutral position. A patient assigned to the lateral group had the tube inserted with the head turned to the right lateral position. When the patient was positioned, a 14-French nasogastric tube was inserted from the ipsilateral (right) nostril, without any further maneuvers of the neck, chin, jaw, or larynx. After two unsuccessful attempts in the intended position, the anesthesiologist was allowed to perform additional maneuvers to aid the successful passage of the nasogastric tube.The number of attempts required for successful insertion was recorded for each patient. The results are summarized in table 1.Fifteen patients were allocated to the lateral group, and 15 were allocated to the neutral group. Passage of the nasogastric tube was successful during the first pass in 12 patients (80%) in the lateral group versus 6 (40%) patients in the neutral group. Three (20%) patients in the lateral group required three or more attempts versus 6 (40%) patients in the neutral group.These results support our observation that passage of the nasogastric tube with the patient’s head turned to the lateral position is associated with a higher success rate than with the neutral position. This technique avoids some of the messy and time-consuming measures of failed nasogastric tube insertions. We now routinely use this method. We also find that the transesophageal echocardiography probe, in the unlocked position, could easily be inserted orally in the same fashion, without having to perform the jaw thrust maneuver.* Singapore General Hospital, Singapore. cchia@doctors.org.uk