Q: We are caring for more patients with left ventricular assist devices in our unit. How do we know when these patients require external chest compressions?-FH, PA
Colleen Halverson, PhD, RN responds-It is increasingly likely that nurses will encounter patients with advanced heart failure (HF) refractory to optimal medical and device-based therapies who have opted for long-term mechanical circulatory support with a left ventricular assist device (LVAD).1
Technologic advances to prolong survival and improve quality of life in patients with advanced HF now include LVADs, either as a bridge to transplant or as a destination therapy for patients who do not meet the criteria as a transplant candidate.2 The number of patients undergoing LVAD implantation greatly increased after the FDA approved their use in 2010 for destination therapy.2 Second-generation LVADs have been implanted in over 22,000 patients.2,3
Newer LVADs provide systemic perfusion with impellers that pump blood from the weakened left ventricle into the aorta. LVADs consist of an inlet tube directing blood from the left ventricle into the pump that operates at speeds of several thousand revolutions per minute, resulting in continuous blood flow into the aorta via a flexible outflow graft.4,5 Thus, patients who have adequate perfusion usually do not have a palpable pulse or measurable BP. Do not assess perfusion in a patient with an LVAD by assessing pulses because these devices result in adequate perfusion without a palpable pulse. A lack of pulse is not an indication for chest compressions in patients with an LVAD.
The American Heart Association provides guidelines for assessing perfusion and initiating CPR in adults with an LVAD.4,6 According to these guidelines, if the patient has an altered mental status, assist ventilation as needed and assess perfusion with skin color and temperature, and capillary refill. If there is adequate perfusion, assess for and treat non-LVAD causes for altered mental status, such as hypoxia or stroke. When signs of adequate perfusion are absent, assess the LVAD function by auscultating for an LVAD hum over the left chest or left upper abdominal quadrant, and looking and listening for LVAD alarms. If the LVAD is not functioning, attempt to restart the LVAD by ensuring secure connections to the LVAD controller, and ensuring sufficient power for the LVAD.4,6 If unable to restart the LVAD, perform external chest compressions for the patient with inadequate perfusion.4,6
If the LVAD is functioning and the ETCO2 is at least 20 mm Hg or the patient has a mean arterial pressure (MAP) greater than 50 mm Hg using a Doppler probe, chest compressions should be withheld because the LVAD is functioning properly and chest compressions are not indicated.4,6 If the LVAD is functioning, but the ETCO2 is not at least 20 mm Hg, or the patient does not have a MAP of greater than 50 mm Hg using a Doppler probe, chest compressions should be performed. Notify the patient's ventricular assist device (VAD) center and consult with the VAD coordinator as soon as possible to optimize the care of these patients.4,6,7
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