OBJECTIVES

Identify the presence of auto-PEEP by assessing a ventilator flow waveform. Explain how manipulation of the inspiratory rise time can improve patient-ventilator synchrony during pressure-targeted ventilation Discuss how the following laboratory tests provide valuable insight into the management of patients receiving mechanical ventilation: - arterial blood gases - serum electrolytes - thyroid function tests - adrenal function tests Explain how to use a simple clinical calculation to determine whether acidosis is pure respiratory or mixed respiratory and metabolic. Review recent research findings supporting a restrictive fluid management protocol in patients with acute lung injury and ARDS. Explain why cardiac output often decreases during weaning when the patient has impaired left ventricular function. Discuss how the use of PEEP can contribute to pulmonary edema formation via its effects on the lymphatic system. Describe the role of inflammatory spread from the abdomen to the lungs via trans-diaphragmatic pathways in the lymphatic system. Describe the relationship between high FIO2’s, impaired innate immune response, and the risk and severity of infectious complications in critically ill patients. Discuss how hyperoxia interacts with mechanical stretch of the lung to augment ventilator-induced lung injury. Describe how resuming spontaneous ventilation during mechanical ventilation can assist in resolution of pulmonary edema. Identify assessment parameters useful in determining whether or not to extubate a patient following a successful spontaneous breathing trial. Explain why sepsis is the most serious and common impediment to weaning success. Explain how ST segment monitoring can be useful when weaning the patient with an evolving or threatening myocardial infarction. Describe a practical approach to monitoring patients during a spontaneous breathing trial, using the following clinical parameters:  - heart rate and blood pressure - respiratory rate - tidal volume - rapid shallow breathing index - minute ventilation recovery time Explain the etiology of transfusion-related acute lung injury (TRALI), including antibodies to leukocytes as well as biological response mediators present in stored blood. State the physiologic explanation concerning the relative risk of TRALI following transfusion of plasma verses transfusion of packed red blood cells. Discuss the role of restrictive transfusion practices in reducing the incidence of TRALI.