Effects of different deflation modes for endotracheal tube cuff on coughing response and hemodynamics during extubation

Objective To investigate the effects of different deflation methods of endotracheal tube cuff on coughing response and hemodynamics during extubation.

Methods Ninety patients undergoing elective surgery for endotracheal intubation under general anesthesia were selected as study subjects and randomly divided into study group and control group, with 45 patients in each group. In the study group, the cuff end of the endotracheal tube cuff was connected to a syringe and a non-liquid pressure gauge through a three-way stopcock. Before extubation, the cuff was aspirated to decrease the cuff pressure at a rate of 3 cmH₂O/s. In the control group, the gas in cuff was rapidly deflated by aspirating all the gas inside with a syringe during extubation. The incidence and severity of coughing response during extubation were recorded in both groups. Mean arterial pressure (MAP) and heart rate (HR) were recorded before induction of general anesthesia (T₀), before cuff deflation (T₁), immediately after cuff deflation (T₂), 1 minute after extubation (T₃), 3 minutes after extubation (T₄), and 5 minutes after extubation (T₅). Adverse events were also recorded in both groups.

Results The coughing response during extubation started immediately after cuff deflation in both groups. The incidence and severity of coughing response were lower in the study group than in the control group (P < 0.05). Compared with the control group, values of MAP were lower at T₂ to T₄ and values of HR were lower at T₂ to T₅ in the study group (P < 0.05). The incidence of post-extubation pharyngeal discomfort was 6.67 % in the study group, which was lower than 26.67 % in the control group (P < 0.05). There was no significant difference in the incidence of post-extubation hypoventilation between the two groups (P>0.05).

Conclusion The method of slowly reducing the pressure of the endotracheal tube cuff at a constant rate can reduce the incidence and severity of coughing, decrease postoperative extubation complications, and stabilize hemodynamics, with better effects than the method of rapidly aspirating all the gas inside the cuff at once.