Laryngopharyngeal Mucosal Injury Due to Nasogastric Tube Insertion during Cardiopulmonary Resuscitation: A Retrospective Cohort Study

Abstract

Background: Patients under cardiopulmonary resuscitation (CPR) are at high risk of aspirating gastric contents. Nasogastric tube insertion (NGTI) after tracheal intubation is usually performed blindly. This sometimes causes laryngopharyngeal mucosal injury (LPMI), leading to severe bleeding. This study clarified the incidence of LPMI due to blind NGTI during CPR.

Methods: We retrospectively analyzed 84 patients presenting with cardiopulmonary arrest on arrival, categorized them into a Smooth group (Smooth; blind NGTI was possible within 2 min), and Difficult group (blind NGTI was not possible), and consequently performed video laryngoscope-assisted NGTI. The laryngopharyngeal mucosal condition was recorded using video laryngoscope. Success rates and insertion time for the Smooth group were calculated. Insertion number and LPMI scores were compared between the groups. Each regression line of outcome measurements was obtained using simple regression analysis. We also analyzed the causes of the Difficult group, using recorded video laryngoscope-assisted videos.

Results: The success rate was 78.6% (66/84). NGTI time was 48.8 ± 4.0 s in the Smooth group. Insertion number and injury scores in the Smooth group were significantly lower than those in the Difficult group. The severity of LPMI increased with NGT insertion time and insertion number.

Conclusions: Whenever blind NGTI is difficult, switching to other methods is essential to prevent unnecessary persistence.

Keywords: cardiopulmonary arrest; cardiopulmonary resuscitation; insertion number; insertion time; laryngopharyngeal mucosal injury; nasogastric tube insertion; video laryngoscope.

Figure 1

A schematic illustrating the complications of nasogastric tube insertion. (a) Video laryngoscopy showing that the nasogastric tube (arrow) is placed in the trachea with the intubation tube; (b) Severe bleeding from the site of mucosal injury during nasogastric tube insertion after initiation of anticoagulation therapy.

Figure 2

Study protocol. One hundred and fifty-nine patients with cardiopulmonary arrest on arrival were referred to our emergency department. Of these, 67 patients were excluded from this study based on criterion 1, and eight were excluded based on criterion 2. Finally, 84 patients (Smooth group: n = 67 and Difficult group: n = 17) were retrospectively analyzed in this study.

Figure 3

Evaluation of laryngopharyngeal mucosal injury after nasogastric tube insertion. (a) Laryngopharyngeal mucosal injury was evaluated using injury scores: 0, no injury; 1, erythema (arrow); 2, hematoma (arrow); 3, more than 10 spots of erythema and hematoma (arrows); and 4, laceration (arrow); (b) The three regions of the laryngopharynx (retropharyngeal wall (arrow indicates the uvula), pharynx (white arrowhead indicates the hypopharynx, and black arrow indicates the vocal cord), and epiglottis/vallecula (arrow indicates the epiglottis)) were evaluated separately. The highest score for each region was defined as the injury score for that region. The sum of the injury scores of the three regions was used as the score for the patient.

Figure 4

Regression lines for the insertion number, insertion time, and injury score. Regression lines are helpful in predicting the injury score (p < 0.05). (a,b) These regression lines suggested that the predicted injury score was low in cases where the nasogastric tube could be inserted blindly within a short duration and with a lower insertion number.