Autonomic tone in medical intensive care patients receiving mechanical ventilation and during a CPAP weaning trial.

Mechanical ventilator support and the resumption of spontaneous ventilation or weaning create significant alterations in alveolar and intrathoracic pressure that influence thoracic blood volume and flow. Compensatory autonomic tone alterations occur to ensure adequate tissue oxygen delivery, but autonomic responses may produce cardiovascular dysfunction with subsequent weaning failure. The authors describe autonomic responses of critically ill patients (n = 43) during a 24-hr period of mechanical ventilatory support and during the 24 hr that included their initial spontaneous breathing trial using continuous positive airway pressure.

Undergraduate and graduate students partnering in a short term transcultural experience in Honduras.

Undergraduate and graduate nursing students were partnered in a short-term transcultural nursing experience in Choluteca Honduras. Learning objectives specific to the level of the student were developed to meet their individual needs with a women's health focus. Learning opportunities were created to encourage interaction between the undergraduate and graduate students.

Prevalence of myocardial ischemia during mechanical ventilation and weaning and its effects on weaning success.

Background: Myocardial ischemia may be considered both a consequence of weaning from ventilation and a potential cause of weaning failure. A limited number of investigations have evaluated myocardial ischemia during mechanical ventilation and weaning and its effect on weaning success. The purpose of this pilot investigation was to determine the prevalence of myocardial ischemia in a diverse group of medical intensive care unit (MICU) patients during baseline mechanical ventilation, during weaning using continuous positive airway pressure, and up to 24 hours after extubation and to evaluate the relationship between ischemia and weaning failure.

Hemodynamic changes during discontinuation of mechanical ventilation in medical intensive care unit patients.

Background: Cardiac dysfunction can prevent successful discontinuation of mechanical ventilation. Critically ill patients may have undetected cardiac disease, and cardiac dysfunction can be produced or exacerbated by underlying pathophysiology.

Objective: To describe and compare hemodynamic function and cardiac rhythm during baseline mechanical ventilation with function and rhythm during a trial of continuous positive airway pressure in medical intensive care patients.

Verification of inefficacy of the glucose method in detecting aspiration associated with tube feedings.

While some authors believe that testing for glucose in suctioned tracheal secretions can be used to detect aspiration of glucose-containing formula, others disagree. Previous evaluative studies of the glucose method's efficacy have lacked adequate statistical power and a gold standard for aspiration. In this animal study, a gold standard for aspiration was used and possessed sufficient statistical power to address the glucose method's sensitivity and specificity.

Endotracheal suctioning: open versus closed with and without positive end-expiratory pressure.

An open system of delivery of supplemental oxygen was compared with a closed system during endotracheal suction (ETS) at zero end-expiratory pressure (ZEEP) and 10 cm H2O positive end-expiratory pressure (PEEP). Four protocols in a 2 x 2 design were administered in random order to 12 anesthetized and oleic acid-injured animals. Statistically significant differences were found between protocols for arterial carbon dioxide tension (PaCO2), arterial oxygen saturation (SaO2), airway pressure (Paw), right atrial pressure (Pra), intrathoracic pressure (Pit), arterial pressure, and right ventricular afterload.

Efficacy of dye-stained enteral formula in detecting pulmonary aspiration.

Study Objective: To determine the extent to which a mixture of human gastric juice and enteral formula stained with two concentrations of FD&C Blue No. 1 food dye (0.8 and 1.

Pepsin as a marker for pulmonary aspiration.

Background: Although assessment for aspiration of small volumes of gastric contents in tube-fed patients receiving mechanical ventilation is important, available methods for this purpose are not wholly satisfactory. A potential method is immunoassay of tracheal secretions for the gastric enzyme pepsin.

Objectives: To determine the frequency with which pepsin in suctioned tracheal secretions from acutely ill, tube-fed patients receiving mechanical ventilation could be detected via an immunoassay.