Neurosurgical patients having GA without neuromuscular blocking more liable to have Intraoperative coughing

A new study found that the incidence of intraoperative coughing was nearly 1.8% in neurosurgical patients undergoing general anesthesia without neuromuscular blockade. High peak inspiratory pressure (PIP) was found to be a significant predictor of intraoperative coughing in these patients. The study results were published in the journal BMC Anesthesiology.

During positive pressure breathing, the airway pressure affects the endotracheal cuff pressure. Intraoperative coughing, which can be hazardous during neurosurgery, may be associated with high endotracheal cuff pressure. Hence Hyongmin Oh et al from the Republic of Korea conducted a study to look at the incidence of intraoperative coughing and its relationship to peak inspiratory pressure (PIP) during neurosurgery under general anesthesia without neuromuscular blockade.

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

Key findings:

• 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 ([4.4%] vs. [1.2%]) and after ([6.3%] vs. [0.5%]) propensity score matching.
• A high PIP, tidal volume divided by predicted body weight, and surgical duration predicted intraoperative coughing in multivariable logistic regression analysis after propensity score matching.

Intraoperative coughing that occurs during neurosurgery is a major concern for anesthesiologists and neurosurgeons. Through the present study, the researchers concluded that high PIP can significantly predict intraoperative coughing in neurosurgical patients who underwent general anesthesia without neuromuscular blockade.

Further reading: Oh, H., Sohn, J.Y., Ma, S. et al. High peak inspiratory pressure may be associated with intraoperative coughing during neurosurgery under general anesthesia without neuromuscular blockade: a retrospective study. BMC Anesthesiol 23, 123 (2023).https://doi.org/10.1186/s12871-023-02080-6