Henry Ford Health System HENRY FORD HOSPITAL Ventricular Assist Device Program: Emergency Department Education Henry Ford Health System

Agenda Definition of a VAD Current LVADs Basic LVAD function & Key differences Stable VAD patient in ED Unstable VAD patient in ED

WHAT IS A VAD? A Ventricular Assist Device (VAD) is a mechanical circulatory support device used to treat heart failure patients. It helps a weakened heart pump blood throughout the body. Although VADs can provide right, left, or biventricular support, the LVAD (left ventricular assist device) is the most common. Patients are usually discharged home on these devices.

* 07/16/96 These pumps differ in technical design, but all are continuous-flow pumps and have the following analogous components: an inflow cannula that is surgically implanted into the left ventricular (LV) apex, serving as a conduit for blood from the LV to the pump; 2) a pump enclosure which houses an impeller that circulates blood; 3) an outflow graft that carries blood from the pump to the systemic circulation; and 4) a surgically tunneled driveline that connects the pump to an external controller that operates and monitors the pump function. The external controller is connected by 2 power cables to a battery powered source or a power module connected to an AC source while batteries are charging. *

Basic LVAD function LVADs move blood from the LV apex to systemic circulation in a continuous manner Controller: Speed (RPM), Flow (L/min), Power (watts), PI (pulsatility index) Pump speed is the fundamental parameter that the provider can alter The system controller monitors power consumption and estimates cardiac output based on speed and power consumption may not be accurate in the case of physiologic derangements (e.g., AI or LVAD dysfunction including pump thrombosis) Additionally, the controller measures temporal power fluctuations to give an estimate of pulsatility through the pump, termed pulsatility index for HeartMate devices and represented graphically as the HVAD pump flow waveform for the HeartWare device Contemporary pump design and operating software are unable to automatically modulate speed or cardiac output based on physiologic demand; therefore, they will operate at the speed the provider sets, consuming as much power as needed to maintain that speed.

* 07/16/96 Key Differences HVAD and HM 3 provide more accurate CO estimates compared to HM 2 HVAD and HM 3 have a larger change in flow for a given pressure gradient change across the pump than HM 2 centrifugal flow pumps are more sensitive to changes in preload and afterload, and controlling hypertension is a key element of normal centrifugal flow pump function HVAD and HM 3 have automated speed modulation capabilities to enhance washing of the pump and allow possible intermittent ejection through the native aortic valve. These rapid speed modulations, termed “Artificial Pulse” for HM 3 and “Lavare Cycle” for HVAD may have benefits in preventing pump thrombosis, AV insufficiency and stroke. -(centrifugal design, and by using the patient’s manually entered hematocrit to estimate the serum viscosity. *

HeartMate II Left Ventricular Assist System * 07/16/96 HeartMate II Left Ventricular Assist System Implantable Pump Batteries The HeartMate II Left Ventricular Assist System consists of an implantable pump, percutaneous lead, microprocessor-based system controller, and portable power source. Percutaneous Lead Controller *

HMII VAD FLOW Press to see flow VAD flow is visible on the power module (circled) and the controller. Click square button on controller to see Liters per min Flow is like cardiac output (3-6 ok)

HeartMate II VAD POWER SOURCES VAD must be connected to AC power or batteries AT ALL TIMES! Batteries last ~10-14 hours. *If patient connected to AC (wall) power and power goes out, power module (PM) will provide only about 20 minutes backup power…switch patient from PM to batteries immediately! HeartMate II drains both batteries simultaneously.

HVAD® System Configuration Controller Battery

HVAD® System Components HVAD™ Controller HVAD™ Pump HVAD™ Monitor HVAD™ Controller AC Adapter HVAD™ Controller DC Adapter HVAD™ Batteries & Battery Charger

HVAD™ Controller Flow and speed on controller screen! Requires two power sources at all times: 2 batteries 1 battery & AC or DC Adapter Batteries 10-16 Hrs Need Doppler to measure BP Doppler opening sound approximates mean arterial pressure (70-90 mmHg goal) in most patients speed flow

HeartMate 3 LVAD Has engineered pulsatility in pump to “mimic” a pulse. May or may not get cuff BP: Goal SBP <110 mmHg Goal MAP 70-90 mmHg Doppler may approximate MAP (if not pulsatile) or SBP! If Doppler 70-100 mmHg probably ok. Doppler here will approximate SBP not MAP because wide pulse pressure in patient

GUIDANCE FOR EMERGENCY MEDICAL SERVICES TEAMS In the event of an emergency, all efforts should be made to direct patients with MCS to their respective MCS/left ventricular assist device (LVAD) centers. It is crucial that emergency medical services personnel make every effort to bring the patient's peripheral equipment needed to maintain LVAD/TAH function (including the batteries, power base unit, and controllers), even if this entails a slight delay in transporting the patient. This equipment will be needed to support the patient until he or she can be transferred to his or her LVAD center.

Major Adverse Events

Stable VAD Patient in Emergency Room Connect patient to power module (PM) to get VAD numbers and obtain basic vital signs. Doppler BP O2 saturation may be inaccurate on VAD Keep patient caregiver with patient. Follow VAD Emergency Department Algorithm. Notify cardiology fellow and VAD coordinator @ (313) 705-0089

Clinical Assessment of a Conscious LVAD patient * 07/16/96 Clinical Assessment of a Conscious LVAD patient History Device parameters and alarms Symptoms of infection; including driveline Symptoms of HF Signs of hemoglobinuria (dark urine) Signs of bleeding Physical exam: Cardiac examination! Measurement of BP Assessment of perfusion by skin temperature and capillary refill since there is often no palpable pulse Assessment of signs of right heart failure (JVD, hepatomegaly) Driveline Device connections Document Flow, speed, power, pulsatility index, rate -no pulse, minimal pulse pressure, and no discernable heart sounds, which makes cardiac assessment difficult *

Pulse Underlying LV contractility AV function LVAD pump speed * 07/16/96 Pulse Underlying LV contractility AV function LVAD pump speed LVAD preload and afterload Assessments of heart rate often require telemetry or electrocardiography instead of palpation of a pulse, which is often absent. *

* 07/16/96 Blood Pressure Propeller inside pump spins blood through providing CONTINUOUS FLOW. Narrow pulse pressure: These patients may not have a radial pulse! Carotid pulse is palpable Due to continuous flow you will likely need a Doppler to get a blood pressure on this patient. The sound you hear when deflating the cuff will often be reflective of the mean arterial pressure (MAP), not systolic. A “perfect MAP” is 70-90 mmHg A dangerously low MAP is ≤50 mmHg Noninvasive BP measurements are difficult in CF LVAD patients due to diminished pulse pressure, and automated BP monitors may fail to measure BP. Doppler ultrasound is recommended as the most reliable noninvasive method to assess BP in CF LVAD patients. -The pressure at which the sound of blood flow returns to the brachial artery is recorded and best described as an opening or Doppler pressure, although in practice it is often called a mean arterial pressure (MAP). If a patient has significant pulsatility, then the opening pressure likely represents systolic BP. If there is low pulsatility, then the opening pressure gives a reasonable estimate of the MAP. Narrow pulse pressure mean Doppler opening pressure is closest to MAP *

VAD Patient Transport Take extra batteries and controller with patient (or just take PM cart with those items inside). Allow caregiver to stay with patient if possible. Patients only admitted to P5 or H5.

VAD Patient EMERGENCY in ER VAD TEAM PAGER: (313) 705-0089 On call 24 hours, 365 days a year If no response, keep paging and call attending CHF/Transplant MD on call.

VAD EMERGENCY PRECAUTIONS Feel carotid pulse- radial pulse may not be present. Be mindful of unique BP measurement needs in VAD patients and pulse ox inaccuracies! 70-90 mmHg perfect for mean arterial pressure ≤50 mmHg is emergent! CHECK LVAD CONNECTIONS! Flow of 3-5L usually perfect. If flow is very low: Bleeding? Tamponade? VAD failure or VAD obstruction?

Approach to the Unconscious LVAD patient * 07/16/96 Approach to the Unconscious LVAD patient If pulse present and Doppler BP > 50mHg: Consider non-LVAD causes for unresponsiveness: - Stroke - Hypoglycemia - Overdose - Hypoxia *

Approach to Hypotension in a Conscious LVAD patient

ACLS Indications ACLS may be needed if Not conscious No carotid pulse Mean arterial pressure ≤50 mmHg by Doppler Oxygenation impairment or signs of malperfusion on exam (color, temperature, capillary refill) Use AHA algorithm on CPR rate, depth, airway management

Adult CPR in LVAD patient VF/VT? Is there a carotid pulse present? Doppler preferred Is patient conscious Check BP: Doppler needed! No No Yes VT/VF resolved but unconscious Yes NO or Yes: While waiting for Coordinator, begin secondary assessment Yes No Are LVAD controller and Batteries Hooked up? Doppler or MAP <50 Doppler or MAP ≥50 Shock per ACLS guidelines No Doppler BP available, Signs of malperfusion or instability No Begin VAD Arrest: Standard ACLS Epi Chest Compressions Shock when indicated Ongoing VT/VF Call Coordinator and on-call Fellow Assess BP and VAD flows every 2 min Call Coordinator VAD Coordinator: (313) 705-0089

VAD Emergencies VT/VF: Patient may or may not be stable on LVAD support Unstable patient: defibrillation ok up to 200 J. Do not disconnect VAD. Don’t stress over pad placement Stable patient: call cardiology fellow Can try amio bolus 150-300 mg. Risks of persistent VT/VF are device clot, RV failure and cardiogenic shock (RV is impacted by VT/VF and LVAD won’t fill). Would not leave in VT/VF for >30 min, even if stable OK to sedate and shock if needed.

Key Facts on VADs Do not get any part of any VAD wet. A carotid pulse is palpable. Radial and femoral pulses are often not palpable. Pulse Ox values are often inaccurate! Usually need a Doppler to measure blood pressure. Good number is an opening pressure of 70-90. Pump flow is what is supplementing cardiac output. Good flow is 3-6 L Defibrillation for VT/VF and CPR is safe. Do NOT disconnect LVAD CPR is provided according to algorithm.

On call 24 hours, 365 days a year TAKE HOME MESSAGE VAD TEAM PAGER: (313) 705-0089 On call 24 hours, 365 days a year If no response, keep paging and call attending CHF/Transplant Cardiology on call. Dr. Cowger is Medical Director of program for any concerns: 734 546 4911 (cell)

References 1. American Heart Association, May 2017. Cardiopulmonary Resuscitation in Adults and Children with mechanical Circulatory Support. A Scientific Statement From the American Heart Association. Peberty, M., Gluck, J. et al. Dallas Texas. AMHA. 2. http://www.thoratec.com/medical-professionals/vad-product-information/heartmate-ll-lvad.aspx 3. https://www.sjm.com/en/professionals/featured-products/heart-failure-management/mechanical-circulatory-support/left-ventricular-assist-device/heartmate-3-left-ventricular-assist-system?clset=af584191-45c9-4201-8740-5409f4cf8bdd%3ab20716c1-c2a6-4e4c-844b-d0dd6899eb3a 4. https://www.heartware.com/ 5. The 2013 International Society for Heart and Lung Transplantation Guidelines for Mechanical Circulatory Support: Executive Summary. The Journal of Heart and Lung Transplantation, Vol 32, No 2, February 2013. http://dx.doi.org/10.1016/j.healun.2012.09.013 6. Waqas M and Cowger JA. Role of Mechanical Circulatory Support. Heart Failure Clinics 2016;12:399-409. PMID: 27371516. 7. Trauma Resuscitation in a Left Ventricular Assist Device Patient: An Emergency Medicine Simulation Scenario. Cureus. 2017 Oct; 9(10): e1773. doi: 10.7759/cureus.1773 8. Algorithms to guide ambulance clinicians in the management of emergencies in patients with implanted rotary left ventricular assist devices. Emerg Med J. 2017 Dec; 34(12): 842–850. doi: 10.1136/emermed-2016-206172 9. Two-Year Outcomes with a Magnetically Levitated Cardiac Pump in Heart Failure. N Engl J Med 2018; 378:1386-1395. DOI: 10.1056/NEJMoa1800866 10. Intrapericardial Left Ventricular Assist Device for Advanced Heart Failure. N Engl J Med 2017; 376:451-460 DOI: 10.1056/NEJMoa1602954.