Effects of Head and Neck Position on Nasotracheal Tube Intracuff Pressure: A Prospective Observational Study

Usefulness of video laryngoscopy in tracheal intubation at thyroid surgical position for intraoperative neuromonitoring

This observational study aimed to compare the glottic view between video and direct laryngoscopy for tracheal intubation in the surgical position for thyroid surgery with intraoperative neuromonitoring. Patients scheduled for elective thyroid surgery with intraoperative neuromonitoring were enrolled. After the induction of anesthesia, patients were positioned in the thyroid surgical posture with a standard inclined pillow under their head and back. An investigator assessed the glottic view using the percentage of glottic opening (POGO) scale and the modified Cormack-Lehane grade in direct laryngoscopy and then video laryngoscopy sequentially while using the same McGRATH™ MAC video laryngoscope at once, with or without external laryngeal manipulation, at the surgical position. A total of thirty-nine patients were participated in this study. Without external laryngeal manipulation, the POGO scale significantly improved during video laryngoscopy compared to direct laryngoscopy in the thyroid surgical position (60.0 ± 38.2% vs. 22.4 ± 23.8%; mean difference (MD) 37.6%, 95% confidence interval (CI) = [29.1, 46.0], P < 0.001). Additionally, with external laryngeal manipulation, the POGO scale showed a significant improvement during video laryngoscopy compared to direct laryngoscopy (84.6 ± 22.9% vs. 58.0 ± 36.3%; MD 26.7%, 95% CI = [18.4, 35.0] (P < 0.001). The superiority of video laryngoscopy was also observed for the modified Cormack-Lehane grade. In conclusion, video laryngoscopy with the McGRATH™ MAC video laryngoscope, when compared to direct laryngoscopy with it, improved the glottic view during tracheal intubation in the thyroid surgical position. This enhancement may potentially facilitate the proper placement of the electromyography tracheal tube and prevent tube displacement due to positional change for thyroid surgery.

Relationship of Endotracheal Tube Cuff Pressures with Changes in Body Positions of Critically Ill Patients on Mechanical Ventilation: An Observational Study

Aims and background

Endotracheal tube cuff pressure (ETCP) is an important factor to determine the development of complications associated with invasive mechanical ventilation. To avoid preventable complications arising out of immobilization, frequent changes in body positioning are necessary. Such variations in body position can affect ETCP in critically ill patients who are on mechanical ventilation. So, our study aimed to assess the effect of changes in body position on ETCP in patients who are on mechanical ventilation.

Materials and methods

This prospective observational study included 31 critically ill intubated patients. Each study subject was first placed in a neutral starting position with a 30º head elevation. Then, they were subjected to a sequential change in body position based on the 16 most used positions as part of the critical care unit's (CCUs) daily routine. Endotracheal tube cuff pressure was measured after each position change. Data were analyzed using standard statistical tests.

Results

Statistically significant difference in ETCP was observed during anteflexion of neck, hyperextension of neck, left lateral flexion of neck, right lateral flexion of neck, left lateral rotation of neck, right lateral rotation of neck, 10o recumbent position, supine position, Trendelenburg position, and right lateral 30° and 45° positions. Maximum increase in ETCP was seen during anteflexion of neck (31 ± 4.5; 22-42 cm H2O).

Conclusion

Our study demonstrates significant deviations in ETCP from the recommended range following changes in the body position of mechanically ventilated patients, highlighting the need for the measurement of ETCP after each position change and maintenance of the same within the target range.

How to cite this article

Roy O, Dasgupta S, Chandra A, Biswas P, Choudhury A, Ghosh S, et al. Relationship of Endotracheal Tube Cuff Pressures with Changes in Body Positions of Critically Ill Patients on Mechanical Ventilation: An Observational Study. Indian J Crit Care Med 2024;28(1):36-40.

High peak inspiratory pressure may be associated with intraoperative coughing during neurosurgery under general anesthesia without neuromuscular blockade: a retrospective study

BACKGROUND

The endotracheal cuff pressure depends on the airway pressure during positive-pressure ventilation. A high endotracheal cuff pressure may be related to intraoperative coughing, which can be detrimental during neurosurgery. We investigated the incidence of intraoperative coughing and its association with peak inspiratory pressure (PIP) during neurosurgery under general anesthesia without neuromuscular blockade.

METHODS

This retrospective study divided 1656 neurosurgical patients who underwent total intravenous anesthesia without additional neuromuscular blockade after tracheal intubation into high (PIP > 21.6 cmH₂O, n = 318) and low (PIP ≤ 21.6 cmH₂O, n = 1338) PIP groups. After propensity score matching, 206 patients were selected in each group. Demographic, preoperative, surgical, and anesthetic data were collected retrospectively from electronic medical records and continuous ventilator, infusion pump, and bispectral index data from a data registry.

RESULTS

Intraoperative coughing occurred in 30 (1.8%) patients, including 9 (0.5%) during the main surgical procedure. Intraoperative coughing was more frequent in the high PIP group than in the low PIP group before (14/318 [4.4%] vs. 16/1338 [1.2%], P < 0.001) and after (13/206 [6.3%] vs. 1/206 [0.5%], P = 0.003) propensity score matching. In multivariable logistic regression analysis after propensity score matching, a high PIP (odds ratio [95% confidence interval] 14.22 [1.81-111.73], P = 0.012), tidal volume divided by predicted body weight (mL/kg, 1.36 [1.09-1.69], P = 0.006), and surgical duration (min, 1.01 [1.00-1.01], P = 0.025) predicted intraoperative coughing.

CONCLUSION

The incidence of intraoperative coughing was 1.8% in neurosurgical patients undergoing general anesthesia without neuromuscular blockade and might be associated with a high PIP.