swallowing depends on the synergistic motion of the tongue, larynx, and pharyngeal wall to develop a bolus pressure gradient for bolus transit. However, few studies have provided timing relationships for clinical evaluations. To examine the timing relationships of pharyngeal anatomic motion, pressure generation, and bolus transit in the normal swallow, this study uses a new method, manofluorography, to correlate these swallowing aspects. Thirty-one events were timed by analyzing five swallows each in 14 normal subjects. A different perspective of pharyngeal physiology is presented.
Acute postobstructive pulmonary edema may occur after airway obstruction. A decrease in intrathoracic and intraalveolar pressures causes an increased blood flow into the pulmonary vasculature and favors the development of pulmonary edema. Two mechanisms for the development of acute postobstructive pulmonary edema are proposed: type 1 follows acute airway obstruction, and type 2 follows relief of chronic airway obstruction.
The fact that pressures in the pharynx are asymmetric has raised questions about the validity of measurements made using manofluorography. Using a special manometric catheter that measures the pressures in four different directions, manofluorography was performed on seven normal volunteers and the measurements in the four directions were compared. When the bolus was not present the measurements were found to be asymmetrical. When the bolus filled the cavity, the measurements were symmetrical. Therefore, manometric measurements made in the pharynx during bolus flow are not invalidated by variations in the orientation of the catheter.
Acute postobstructive pulmonary edema may occur after airway obstruction. A decrease in intrathoracic and intraalveolar pressures causes an increased blood flow into the pulmonary vasculature and favors the development of pulmonary edema. Two mechanisms for the development of acute postobstructive pulmonary edema are proposed: type 1 follows acute airway obstruction, and type 2 follows relief of chronic airway obstruction.
Measurement of pressures in the pharyngeal esophageal segment (P-E segment) is complicated by the vertical motion and by the rapidly changing pressures in the segment. The sensors move superiorly and interiorly with respect to the P-E segment during the swallow. This study examines the validity of manofluorographic measurements taken in the P-E segment by using a catheter with sensors spaced at 1 cm intervals. Seven normal volunteers were tested. Measurements were similar using one sensor and using an average of five sensors. During the time of bolus passage, the P-E segment is open and the bolus itself equalizes pressures measured within the bolus.
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