Exam 46: Physiology of Ventilatory Support

Patients receiving mechanical ventilation are usually turned every 2 hr to prevent which of the following? 1) Atelectasis 2) Secretion retention 3) Pressure sores 4) Hyperoxemia

Primary indications for using positive end expiratory pressure (PEEP) in conjunction with mechanical ventilation include which of the following? 1) When dynamic hyperinflation occurs in chronic obstructive pulmonary disease (COPD) patients. 2) When the imposed work of breathing is excessive. 3) When acute lung injury causes refractory hypoxemia.

After accounting for the compressed volume loss on a stable adult patient receiving volume-controlled continuous mandatory ventilation at a preset volume of 500 ml, you still note a 150-ml difference between the expected and the actual delivered volume. Which of the following is most likely causing this problem?

In which of the following types of ventilation can pleural pressure become positive during inspiration? 1) Positive-pressure ventilation 2) Spontaneous ventilation 3) Negative-pressure ventilation

During ventilatory support, peak inspiratory pressure (PIP) is the pressure needed to overcome which of the following? 1) Chest wall compliance 2) Lung compliance 3) Airway resistance 4) Systemic arterial pressure

Which level of FiO₂ and what time of exposure has been associated with oxygen toxicity? 1) FiO₂ of 0.5 2) FiO₂ of 0.7 3) FiO₂ of 0.6 4) 24 to 48 hr

What factors contribute to the development of auto-positive end expiratory pressure (PEEP)? 1) High expiratory Raw 2) High inspiratory flows 3) Inadequate expiratory time

Positive-pressure ventilation (PPV) can reduce urinary output by how much?

What does pressure-supported ventilation consist of?

Which of the following strategies are useful in the management of shunt? 1) Positive end expiratory pressure 2) Permissive hypercapnia 3) Control of membrane permeability

Assuming a constant rate of breathing, which of the following inspiratory-to-expiratory (I:E) ratio would tend to most greatly impair a patient's systemic diastolic pressure?

Bilevel positive airway pressure (BiPAP) is used for which of the following purposes? 1) Nocturnal ventilatory support of chronic disease patients 2) Preventing intubation of patients with acute exacerbations of chronic obstructive pulmonary disease (COPD) 3) Treatment of obstructive sleep apnea (OSA) in the home 4) Providing ventilatory support for patients with status asthmaticus

Which of the following is considered a normal spontaneous tidal volume?

Which of the following variables determine the level of support achieved with adaptive support ventilation? 1) Patient effort 2) Flow 3) Time constant

In which of the following types of ventilation is alveolar expansion during inspiration due to a decrease in pleural pressure? 1) Positive-pressure ventilation (PPV) 2) Negative-pressure ventilation (NPV) 3) Spontaneous ventilation

Beneficial physiological effects of positive end expiratory pressure (PEEP) include which of the following? 1) Increased PaO₂ for given FiO₂ 2) Increased lung compliance (C_L) 3) Decreased shunt fraction 4) Increased functional residual capacity

In which of the following modes of ventilatory support would the patient's work of breathing be least?

Which of the following are true about continuous positive airway pressure (CPAP)? 1) It maintains alveoli at greater inflation volumes. 2) It holds airway pressure essentially constant. 3) It provides the pressure gradient needed for ventilation. 4) It has side effects similar to those of positive pressure ventilation.

In which of the following modes of ventilatory support would the patient's work of breathing be greatest?

Which of the following is the recommended tidal volume for mechanical ventilation in patients with COPD?