Inserting a nasogastric tube into anesthetized and intubated patients is sometimes very difficult and traumatic. After several failed attempts, complication rates usually increase. Threading the pliable NGT through probable anatomic obstacles without any manipulations or facilities is challenging.
Therefore, some authors suggest the compression of the ipsilateral lateral neck at the level and lateral border of the thyrohyoid membrane to transiently collapse the ipsilateral piriform sinus and slightly move the arytenoids cartilage so that the NGT can more easily pass through via the lateral or posterior hypopharynx [6
]. Deflation of the cuff of the endotracheal tube can release the compression over the esophagus and improve NGT passage. The methods adopted, which have high success rates, include the use of a slit endotracheal tube placed via the nasoesophageal route [2
], a laryngoscope with a Magil forcep [12
], a GlideScope for placement [13
], or gloved finger steering to navigate the NGT [14
]. However, these methods may be difficult in patients with limited mouth opening and cervical spine injuries, and some of these methods may be time-consuming in preparation or performance. Other authors suggest forward neck flexion [15
], head rotation [1
], or forward displacement of the larynx [7
] to facilitate the threading of the NGT more smoothly through lateral or posterior hypopharynx spaces; the NGT can then enter the esophageal opening [1
]. Gupta D et al. [16
] suggests inflation with air via a facepiece to open the upper esophageal sphincter.
Considering the faults of NGT’s material properties, some authors suggest stiffening the NGT before an insertion [3
]. The suggested methods include immersion of the NGT in ice-cold water [17
], keeping the NGT in a refrigerator [18
], using a water-fill method [3
], freezing the NGT with distilled water [4
], choosing a large-caliber NGT [8
], or introducing guidewire [21
], forcep [19
], or guitar string [20
] into the NGT before use. These steps significantly reduce NGT kinking and improve the success rate of insertion.
The use of a slit endotracheal tube may cause obvious mucosal damage and bleeding [2
]. Deflation of the cuff of the endotracheal tube, freezing the NGT with distilled water [4
], and the water-fill method are of concern in patients who have not fasted to avoid pulmonary aspiration or regurgitation. The insufflation of air in the oropharynx might possibly lead to regurgitation and aspiration despite the presence of a cuffed tracheal tube and adequate starvation [16
]. Forward displacement of the larynx occasionally causes bradycardia via vasovagal reflex due to compression of the bilateral carotid arteries [22
]. Forward neck flexion sometimes causes increased peak pressure of air way when the endotracheal tube bends. Our novel method is free from these limitations.
In our study, the success rate of NGT intubation in Group S on first attempt was significantly higher than that in Group C (94.3% vs. 54%, p
0.01). The highwayman’s hitch is used to bind together the tips of the NGT and the “Rusch” intubation stylet on their distal ends (introduced to the lower esophagus), and it can be quickly released with a very light tug of the proximal end (outside of the nostril). Tying a highwayman’s hitch is easy to learn, and both the “Rusch” intubation stylet and the surgical silk sutures (70
cm in length, size 3–0) are readily available in operation rooms.
In the control group, successful rescues of failed cases were achieved in 17/18 patients (94.4%) by using this new technique with an intubation stylet as an introducer. Sixteen patients were rescued successfully on the first attempt. We recommend this novel technique not only due to the high success rate on the first attempt in common cases, but also because of the high rescue rate for difficult cases. Because of the limited number of rescue cases in our study, further studies will need to evaluate this outcome.
The mean insertion time was 39.5
s in Group C and 40.3
s in Group S. There was no statistical difference in the mean insertion time between the two groups. The insertion time was defined as the procedure of intubation and did not include the time needed to tie the highwayman’s hitch. If this was included, the insertion time in Group S would be a little longer. However, it can take only a few seconds to tie a highwayman’s hitch with practice.
A total of 18 of the 103 study patients developed complications. Kinking of the NGT occurred in 9 patients (18%) in Group C but in no patients in Group S. Using a 2.6-mm “Rusch” intubation stylet as an introducer makes it easy to guide the NGT through sites of impaction and up to 40
cm deep into the nostril without any kinking or knotting. Insertions using smaller size NGTs or softer silicone stomach tubes have kinking more often, and these may particularly benefit from the usage of this method.
Another common complication was nasal mucosal bleeding. This occurred in 6 patients (12%) in Group C and also in 6 patients (11.3%) in Group S. All of these complications involved mucosal blood tinged, not active bleeding, and no blood entered the mouth. None of these patients needed further medical or surgical treatment. Although the NGT tied with a 2.6-mm “Rusch” intubation stylet in Group S had a larger diameter, it did not cause more complications of nasal mucosal bleeding than the single NGT used in Group C. In some studies, the patients’ nostrils were prepared with vasoconstrictors to lessen the occurrences of bleeding. We did not use any vasoconstrictors to prepare the nostrils of patients in this study. Several reports have revealed other complications (knotting and tracheal insertion) during NGT insertion [23
]. The incidences of knotting and tracheal insertion were not observed in our study, and this might be due to inadequate sample size to evaluate these complications.
If the “Rusch” intubation stylet is replaced by a fiberoptic scope for guiding NGT insertion, physicians would benefit from direct vision of the procedure. However, comparisons with a firberoptic-guided method using a slipknot to insert a NGT still require further investigation.
The average patient height in our study was 160
cm (range from 140 to 179
cm). The “Rusch” intubation stylet used in this study was only 40.5
cm in length. It is possible that in taller patients, the length of the stylet might not be sufficient to reach the gastroesophageal junction. The potential success rate of the technique on taller patients is unknown.
Some reliable methods need to open patient’s mouth including a slit endotracheal tube, a laryngoscope with a Magil forcep, a GlideScope for placement, and gloved finger to navigate the NGT [2
]. Our method does not require oral manipulations. In this regard, our technique might have potential role on patients with limited mouth opening or other difficult airways. Additional studies are needed to precisely elucidate whether our method had beneficial effects on those patients.