Pilbeams Mechanical Ventilation Chapter 4.docx

What is the primary purpose of ventilation? - correct answer To maintain homeostasis and maintain adequate gas exchange and Acid Base balance What are the physiological objectives of Mechanical Ventilation? (3) - correct answer 1. Support or manipulate pulmonary gas exchange ~ Alveolar ventilation ~ Alveolar Oxygenation 2. Increase lung volume ~Atelectasis - treat/prevent ~ Maintain/restore FRC 3. Reduce WOB clinical objectives of mechanical ventilation (8) - correct answer reverse acute respiratory failure, reverse respiratory distress, reverse hypoxemia, prevent or reverse atelectasis and maintain FRC, reverse respiratory muscle fatigue, permit sedation or paralysis (or both), reduce systemic or myocardial oxygen consumption, and minimize associated complication and reduce mortality What are the three parts of initial assessment for a patient in respiratory distress? - correct answer 1. LOC 2. Appearance and texture of patient's skin 3. Patient's vital signs What are the three criteria for ARF to be considered present in a patient? - correct answer 1. PaO2 below predicted normal range for age and atm 2. PaCO2 50mmHg and rising 3. A falling ph of 7.25 and lower What are the two forms of ARF? - correct answer 1) Acute hypoxic respiratory failure (lung failure) 2) Acute hypercapnic respiratory failure (pump failure) What is hypoxemic respiratory failure and the criteria? - correct answer Acute life-threatening or vital organ threatening tissue hypoxia PaO2 60mmHg on FiO2 greater than or equal to 0.50 PaO2 40mmHg on any Fio2; SaO2 90% What can cause hypoxemic respiratory failure? - correct answer Severe V/Q mismatching, diffusion defects, R to L shunting, alveolar hypoventilation, aging, and inadequate inspired O2 How is hypoxemic resp. failure treated? - correct answer Supplemental O2 PEEP CPAP What is acute hypercapnic resp. failure? - correct answer Acute ventilatory failure occurs when a person cannot achieve adequate ventilation to maintain a normal PaCO2 What does the ventilatory pump consists of? - correct answer Respiratory muscles Thoracic Cage Nerves controlled by the reps center in the brainstem What are the three elements of achieving a successful outcome - correct answer 1. Administer supplemental oxygen 2. Maintain a patent airway 3. Continuous monitoring of oxygenation and ventilation status w/ pulse oximetry and ABG analysis What disorders lead to ventilatory pump failure? - correct answer CNS disorders Neuromuscular disorders disorders that increase WOB {see pg. 46 box 4.2 for more details} How often should RT's monitor MIP & VC, and what are critical values? - correct answer MIP and VC should be monitored every 2-4 hours to monitor changes in resp. status MIP of -20 to 0 cmh2o VC lower than 10-15mL/kg What are the critical values indicating ARF and the need for Mechanical Ventilatory support? Ventilation and Oxygenation* - correct answer pH 7.25 PaCO2 55mmHg and rising Vd/Vt 0.6 PaO2 70mmHg (on O2 greater than or equal to 0.60) P(A-a)O2 450mmHg on supp. O2 PaO2/PAO2 0.15 PaO2 / Fio2 200 In patient's with neuromuscular disorders what two measurements would be the most helpful in determining the need for mechanical ventilation? - correct answer MIP and VC