Category: Critical Care Nursing Positive pressure ventilation has a direct impact on the lungs. Whether delivered as a set volume or set pressure, invasive positive pressure ventilation forcibly distends the lung. It can be injurious causing volutrauma and barotrauma.
Category: Critical Care Nursing Propofol's ability to penetrate the blood-brain barrier rapidly and distribute into peripheral tissues is responsible for the rapidity and short duration of its clinical effect. Propofol can precipitate hypotension by increasing venous capacitance.
Category: Critical Care Nursing After intubation, additional neuromuscular blocking agents should generally be used only when poor ventilator synchrony interferes with ventilation sedation and analgesia. This may be particularly true in patients with ARDS.
Category: Critical Care Nursing Intubation, mechanical ventilation and paralysis are a significant cause of pain and anxiety for patients, and analgesia and sedation are required to promote patient comfort and patient-ventilator synchrony.
Category: Critical Care Nursing CPAP provides constant positive pressure throughout the respiratory cycle, whereas BiPAP alternates between higher pressure during inspiration (IPAP) and lower pressure during expiration (EPAP).
Category: Critical Care Nursing PEEP increases intrapulmonary and intrathoracic pressures and may affect pulmonary and cardiovascular physiology. Potential adverse effects of PEEP include decreased cardiac output, lung overdistention and pneumothorax.
Category: Critical Care Nursing During acute respiratory failure, lung volumes are typically decreased. The application of PEEP increases functional residual capacity, improves oxygenation and decreases intrapulmonary shunting.
Category: Critical Care Nursing Regardless of the ventilatory mode chosen, PEEP is often used during invasive mechanical ventilation. PEEP refers to the maintenance of positive airway pressure after the completion of passive exhalation.
Category: Critical Care Nursing Synchronized intermittent mandatory ventilation (SIMV) provides intermittent ventilatory support to patients by delivering mandatory and spontaneous breaths. In SIMV, a mandatory breath is given at a preset rate.
Category: Critical Care Nursing Continuous mechanical ventilation (CMV) is intended to provide full ventilatory support. However, if a patient generates negative pressure, representing respiratory effort, on CMV, that breath will be assisted by the ventilator.
Category: Critical Care Nursing The term ventilator mode refers specifically to the amount of respiratory support provided by the ventilator. The most common ventilator modes can be categorized on the basis of how often the ventilator will initiate a breath for the patient.
Category: Critical Care Nursing In volume-controlled ventilation, a breath is defined by delivery of a set tidal volume to the lungs. Inspiratory volume and flow rate are set by the provider and inhalation ends once a preset tidal volume has been delivered.
Category: Critical Care Nursing In pressure-controlled ventilation (PCV), a set amount of pressure is applied to the airway to expand the lungs for a specified amount of time. During PCV, the target pressure and inspiratory time are set by the provider.
Category: Critical Care Nursing How the ventilator defines a breath is referred to as the control variable. The ventilator can give breaths based on delivery of a set pressure or a set volume, referred to as pressure-controlled ventilation and volume-controlled ventilation.
Category: Critical Care Nursing The primary considerations regarding initiation of mechanical ventilation relate to how each breath should be delivered. This includes how a breath is defined, size, duration, frequency and the degree of interaction the patient has with the ventilator.