Effects of morphine and midazolam on pharyngeal function, airway protection, and coordination of breathing and swallowing in healthy adults.

Background: Drugs used for sedation in anesthesia and intensive care may cause pharyngeal dysfunction and increased risk for aspiration. In this study, the authors investigate the impact of sedative doses of morphine and midazolam on pharyngeal function during swallowing and coordination of breathing and swallowing.

Methods: Pharyngeal function, coordination of breathing and swallowing, and level of sedation were assessed by manometry, videoradiography, measurements of respiratory airflow, and a visual analog scale in 32 healthy volunteers (age 19 to 35 yr).

Pharyngeal function and breathing pattern during partial neuromuscular block in the elderly: effects on airway protection.

Background: Intact pharyngeal function and coordination of breathing and swallowing are essential for airway protection and to avoid respiratory complications. Postoperative pulmonary complications caused by residual effects of neuromuscular-blocking agents occur more frequently in the elderly. Moreover, elderly have altered pharyngeal function which is associated with increased risk of aspiration.

Breathing and swallowing in normal man--effects of changes in body position, bolus types, and respiratory drive.

Background: Coordination of breathing and swallowing is essential for airway protection and dyscoordination may cause morbidity and mortality.

Methods: Using a recently developed technique for high accuracy respiratory measurements of airflow during swallowing, we investigated the effects of body position (upright vs left lateral), bolus type (spontaneously swallowed saliva vs water), and respiratory drive (normo- vs hypercapnia) on coordination of breathing and swallowing in 32 healthy volunteers.

Key Results: Swallows were in all cases (100%) proceded by expiration and 98% were also followed by expiration, regardless of body position, bolus type, or respiratory drive.

Swallowing and respiratory pattern in young healthy individuals recorded with high temporal resolution.

The coordination of swallowing and respiration is essential for a safe swallow. Swallowing consists of several subsecond events. To study this, it is important to use modalities with high temporal resolution.

Co-ordination of spontaneous swallowing with respiratory airflow and diaphragmatic and abdominal muscle activity in healthy adult humans.

Co-ordination of breathing and swallowing is essential for normal pharyngeal function and to protect the airway. To allow for safe passage of a bolus through the pharynx, respiration is interrupted (swallowing apnoea); however, the control of airflow and diaphragmatic activity during swallowing and swallowing apnoea are not fully understood. Here, we validated a new airflow discriminator for detection of respiratory airflow and used it together with diaphragmatic and abdominal electromyography (EMG), spirometry and pharyngeal and oesophageal manometry.