Critical Care Flashcards
Reflects left ventricular end-diastolic pressure
Pulmonary artery Wedge Pressure (PAWP)
What is the volume of blood within the ventricle at the end of diastole called?
Preload
Reflects right ventricular end-diastolic pressure and volume depletion or overload
Central Venous Pressure
Forces opposing ventricular ejection
Afterload
Systemic venous resistance and arterial pressure indicate?
Left ventricular afterload
Peripheral vascular resistance and pulmonary arterial pressure indicate
Right ventricular afterload
Increased preload does what to Cardiac Output?
increases it
Increased afterload does what to cardiac output?
decreases it
How often should arterial lines be changed?
q96h
What two invasive pressure monitors assess cardiac function and fluid volume status?
Pulmonary artery diastolic pressure and PAWP
What is used to monitor Pulmonary Artery Pressure?
PA flow-directed catheter (e.g. Swan-Ganz)
What are the two proximal lumens in a Swan-Ganz used for?
Central venous pressure monitoring, injecting fluid for cardiac output, drawing blood, and administering fluids or drugs
What is the distal port used for in a Swan-Ganz?
Thermistor port
Increased systemic vascular resistance indicates what?
vasoconstriction
Decreased systemic vascular resistance indicates what?
vasodilation
Central venous pressure measures what?
Central venous oxygen saturation and indicates volume status
Pulmonary artery catheters measure what?
Mixed venous oxygen saturation (SvO2) to see if gas exchange is occurring
SvO2 and ScvO2 reflect what?
the balance between oxygenation of arterial blood, tissue perfusion, and tissue oxygen consumption
Normal venous O2 concentration is what?
60-80%
What is the tidal volume normal set at on a mechanical ventilator?
6-7 mL/kg
What is the FiO2?
Fraction of inspired oxygen, usually >21% (room air) if ventilated
Positive end-expiratory pressure is used for what and what pressure is typical?
PEEP maintains alveolar inflation and functional reserve. It is normally between 5-10 cm H2O.
In which mechanical ventilatory mode does the ventilator do all of the WOB?
Controlled Ventilatory support
In which mechanical ventilatory mode does the ventilator and patient share the WOB?
Assisted Ventilatory support
Which ventilation mode delivers a present Vt at a preset frequency and when the patient initiates a breath, the preset Vt is delivered?
Assist-Control (A/C) ventilation
Which ventilator mode delivers a preset Vt at a preset frequency in synchrony with the pt’s spontaneous breathing. In between delivered breaths, the patient is able to breath spontaneously. The pt receives a preset FiO2, but self regulates the rate and volume of spontaneous breaths.
Synchronized intermittent mandatory ventilation
Which ventilator mode gives positive pressure to the airway only during inspiration in conjunction with spontaneous respirations. The machine senses spontaneous effort and supplies rapid flow of gas at initiation of breath. The patient determines the inspiratory length, Vt, and respiratory rate.
Pressure support ventilation
Positive pressure is applied to airway during exhalation, preventing alveolar collapse.
Positive end-expiratory pressurje
Pressure is delivered continuously during spontaneous breathing. There is increased WOB.
Continuous positive airway pressure (CPAP)
Delivers oxygen and two levels of positive pressure support. Higher inspiratory positive airway pressure and lower expiratory positive airway pressure. The patient must be able to breathe spontaneously.
Bilevel positive airway pressure (BiPAP)
Delivery of a small Vt at a rapid respiratory rate
High-frequency oscillatory ventillation
Nitric Oxide causes what and is used to treat what?
Pulmonary vasodilation, ARDS
What special considerations are there for the prone patient?
No NAPs!
Dobutamine is used in what type of shock? What effects does it have?
Cardiogenic shock and septic shock
Increased myocardial contractility
Decreases SVR/PAWP
Increases CO/SV/CVP
What are the nursing considerations for dobutamine?
Administer via central line (avoids tissue sloughing)
Monitor HR/BP (hypotension may occur, requiring vasopressor)
Do not administer in same line as NaHCO3 (sodium bicarb)
Dopamine is used in what type of shock? What effects does it have?
Cardiogenic shock
Increases myocardial contractility
Increases HR/CO/BP/MAP, blood flow to renal/mesenteric/cerebral circulation
Anticoagulant/antiinflammatory/vasoconstrictive effects