[Ventilator-associated pneumonia (VAP) : A risk already at the time of anesthetic induction]

Efficacy of sedation with dexmedetomidine plus propofol during esophageal endoscopic submucosal dissection

BACKGROUND AND AIM

During endoscopic submucosal dissection for superficial esophageal cancer, patient body movement can sometimes occur, which may cause discontinuation of the procedure. Propofol and dexmedetomidine have recently been found to be useful sedatives for endoscopic submucosal dissection. This study investigated whether sedation using propofol plus dexmedetomidine can suppress the patient's body movements during esophageal endoscopic submucosal dissection and compared this combination with sedation using propofol alone.

METHODS

This was a prospective double-blind randomized controlled trial. Patients with superficial esophageal cancers who underwent esophageal endoscopic submucosal dissection at Yokohama City University Hospital were prospectively enrolled and were randomly assigned to the propofol and the propofol plus dexmedetomidine groups. The primary endpoint was the incidence of restlessness. The secondary endpoints were the satisfaction score, maintenance dose of propofol, and number of rescue propofol injections.

RESULTS

Sixty-six patients (propofol group: n = 33; combination group: n = 33) were included. The combination group had a significantly lower incidence of restlessness than the propofol group (3.0% vs 27.3%, P = 0.02). In the combination group, the satisfaction scores of the endoscopists were significantly higher, the maintenance dose of propofol was significantly lower, and the number of rescue propofol injections was lower than those in the propofol group (3.0% vs 18.2%, P < 0.001). Although the incidence of bradycardia was significantly higher in the combination group (30.3% vs 3.0%, P < 0.01), no serious adverse effects occurred.

CONCLUSION

The propofol plus dexmedetomidine combination provided excellent sedation that effectively suppressed the patient's body movements during esophageal endoscopic submucosal dissection.

Endotracheal tube cuff pressure changes during manual cuff pressure control manoeuvres: An in-vitro assessment

BACKGROUND

Endotracheal tube (ETT) cuffs are designed to seal the lower airway for precise ventilation and to protect against ingress of pathogens from the pharyngeal space. Therefore, a minimal continuous cuff pressure must be maintained. Aim of this study was to analyse the course of cuff pressure in an in-vitro model during manual cuff pressure control manoeuvres.

METHODS

An artificial trachea was intubated with an appropriately sized ETT and cuff pressure set to 20 cm H₂ O. Thirty-two experienced ICU nurses each performed six cuff pressure control manoeuvres (three times in two different ETTs) using a manual cuff pressure manometer. Course of cuff pressure from connecting the manometer to disconnecting it from the cuff pilot balloon was recorded using a pressure transducer.

RESULTS

There were 190 cuff pressure control manoeuvres suitable for analysis. In all control manoeuvres a cuff pressure below 20 cm H₂ O was noted. In 20.0% of the control manoeuvres the cuff pressure dropped below 10 cm H₂ O. Cuff pressure drops were mainly caused by initially connecting the manometer to the pilot balloon, less frequently by manipulating the pressure gauge of the manometer. Disconnecting the manometer after the control manoeuvre caused a cuff pressure drop in 78.1% of cases, contributing to a final cuff pressure below 20 cm H₂ O in 31.3% of control manoeuvres.

CONCLUSION

Routine manual cuff pressure control manoeuvres in ETT cuffs result in considerable cuff pressure drops. This may have an impact on silent aspiration of pharyngeal contents passing along the cuff into the lower airway.