34. HM II System Controller
Microprocessor that:
• Delivers power to the pump
• Controls pump speed and power
• Monitors, interprets & responds to system performance
• Performs diagnostic monitoring
• Indicates hazard and advisory alarms
• Provides complete backup system
• Event recording capability
36. Field Considerations
• A patient can be in a lethal arrhythmia
and be asymptomatic. Treat the patient
not the monitor.
• Do not cardiovert/defib unless the
patient is unstable with the arrhythmia.
• Electrical shock from cardiovert/defib
will not damage any of the VAD
37. Field Considerations
• Chest Compressions are NOT
recommended. Chest compressions
can disrupt the implanted equipment
causing massive hemorrhaging.
38. HeartMate II Patient Managem
• Most often no way to • NO MRI – CT scan okay.
check a BP – Good
nursing assessment. • Sterile dressing change
to driveline site.
• No palpable pulse in
pt., heart is “beating”, • VAD speed is a set rpm.
but pump is propelling • Frequent labs to check
all the blood from the Pro-BNP, LFT’s, BUN/Cr.
left ventricle & aortic
valve remains closed. • Document pump speed,
• Optimization of heart pump flow, pump power.
failure med regimen. • Patients log daily pump
• INR 1.5-2.0 – STRICT #’s and weights @
39. HeartMate II Emergency
• No chest • Sinus rhythm is best,
compressions, all but if pt. goes in to VT
other ACLS protocols or VF, they are
apply. supported by the
• Controller does NOT pump!
need to be • Most emergencies
disconnected for related to patient
external defibrillation. physiology (i.e. low
• Red Heart alarm on BP, arrhythmias, could
pump indicates LOW be an MI etc.)
FLOW. • Pt. has backup
controller if needed.
40. VAD Patient F/U
• Weekly clinic visits for first 4-6 weeks post d/c to
home.
• Clinic visits every 2 weeks for next 4-6 weeks.
• Then can stretch visits out to every 4 or even 6
weeks.
• Contact by phone weekly to discuss daily log in
between visits.
• VAD team acts as PCP’s for patients.
• VAD patients know not to see a dentist before
clearing with us.
• VAD patients know not to start a new script or
41. VAD Resuscitation Measures
1. DO NOT unplug / remove equipment
2. Assess vitals (C-A-B)
Non-pulsatile flow requires doppler
MAP 70-80, keep < 90 mmHg
Pulse oximetry, NIBP likely inaccurate
1. NO CPR
2. Obtain immediate trained assistance
Family / caregivers are highly trained
42. VT or VF
• STABLE
– Patient may “feel funny” “light headed” or
“different”
– Pump speeds / flows normal or low normal
– Consider cardioversion in consult with VAD center
• UNSTABLE
– Patient unresponsive or evidence poor perfusion
43. Showering Outer Skirt
Inner Pouch
• Allowed once exit site healing Vent Connector Tubing
• Keep exit site as clean & dry as possible
• Use shower kit to protect external components
• Preparing to shower:
– Remove vent connector tubing from inner pouch & discard
– Hang kit over shoulder or neck & adjust strap
– Raise outer skirt
– Lift Velcro tabs & open inner pouch
NYHA Classification - The Stages of Heart Failure In order to determine the best course of of therapy, physicians often assess the stage of heart failure according to the New York Heart Association (NYHA) functional classification system. This system relates symptoms to everyday activities and the patient's quality of life. Class Patient Symptoms Class I (Mild) No limitation of physical activity. Ordinary physical activity does not cause undue fatigue, palpitation, or dyspnea (shortness of breath). Class II (Mild) Slight limitation of physical activity. Comfortable at rest, but ordinary physical activity results in fatigue, palpitation, or dyspnea. Class III (Moderate) Marked limitation of physical activity. Comfortable at rest, but less than ordinary activity causes fatigue, palpitation, or dyspnea. Class IV (Severe) Unable to carry out any physical activity without discomfort. Symptoms of cardiac insufficiency at rest. If any physical activity is undertaken, discomfort is increased.
A computer controller, a power pack, and a reserve power pack remain outside the body. Often times patients will have additional computer controllers and up to three sets of batteries. There are two batteries located beneath each arm. This way one can be switched out while the other maintains the pump. If able, bring additional charged batteries to ED if family has not already done so.
Pulsatile – Uses pneumatics to circulate blood. These are loud devices and ventricular rate can be assessed by simply listening to the machine. These patients will have a pulse and blood pressure although it may be faint. Older first generation type models. Non-Pulsatile – Continuous flow that work with an impeller similar to a fire pump. These devices are quiet and cannot be heard outside the patient. Auscultation of the apex of the left ventricle will produce a smooth humming sound to ensure device is functioning. Patients will have weak or no pulses. The patient will additionally may have narrow pulse pressures and often difficult to obtain with automatic BP monitors.
Pulsatile – Uses pneumatics to circulate blood. These are loud devices and ventricular rate can be assessed by simply listening to the machine. These patients will have a pulse and blood pressure although it may be faint. Older first generation type models. Non-Pulsatile – Continuous flow that work with an impeller similar to a fire pump. These devices are quiet and cannot be heard outside the patient. Auscultation of the apex of the left ventricle will produce a smooth humming sound to ensure device is functioning. Patients will have weak or no pulses. The patient will additionally may have narrow pulse pressures and often difficult to obtain with automatic BP monitors. Pulsatile Older first generation models Non-Pulsatile Second / Third Generation Models
Hundreds of children in the United States are born each year with failing hearts, and often the only hope is transplant. Unfortunately many are not able to survive long enough to find a suitable donor heart. As children's hearts continues to deteriorate, doctors turn to bridging therapie
Thrombus found in the inlet bearing ball and bearing cup upon dismantle of the HeartMate II LVAD. Baseline LVAD settings were speed of 10,000 rpm, pulsatility index of 5.7, power consumption of 7.6 W, and flow of 6.7 l/min. At the time of his readmission, echocardiogram demonstrated a distended left ventricle, elevated pulmonary artery pressures, and an aortic valve opening with each cardiac cycle. Although he clinically appeared to have inflow obstruction, his inflow cannula was well positioned had low velocity flow. LVAD settings were increased to 10,800 rpm; pulsatility index remained at 5.5, power consumption was 7.8 W, and flow was 4.8 l/min. Since the thrombus was in the inlet bearing ball and cup, it did not lead to increased power consumption, as would be the case if the thrombus was in the impeller itself. A HeartMate II was implanted as a bridge to transplant. The patient was transfused fresh-frozen plasma for gross hematuria 5 months later. He developed heart failure and evaluation revealed left ventricular assist device (LVAD) dysfunction. He underwent LVAD exchange (Video 1). A thrombus was noted in the inlet bearing ball and bearing cup (Fig. 1).
A 53-year-old man presented with acute ST-elevation myocardial infarction and cardiogenic shock, due to proximal left main stem artery occlusion. Recovery was complicated by end-stage ischemic heart failure, and he was referred for left ventricular assist device (LVAD) implantation 2 months after his original presentation. A HeartMate II LVAD was implanted via a median sternotomy with cardiopulmonary bypass. He had an uneventful postoperative recovery and was started on clopidogrel and heparin infusion. Antithrombin 3 levels were in the normal range, and the activated partial thromboplastin time was 60–100 sec at all times. On postoperative day 9, he developed sudden severe hemodynamic compromise, and the LVAD stopped working. An emergency re-sternotomy showed that the LVAD was completely blocked by blood clots in the inflow and outflow cannulae (Figure 1). The LVAD was explanted and replaced with a CentriMag Levitronix system as a salvage operation. After 6 weeks, the CentriMag Levitronix system was replaced with a new HeartMate II LVAD, and the patient was started on heparin and aspirin. Later, heparin was changed to warfarin. The LVAD revealed diffuse thrombosis with no evidence of mechanical failure. Screening of the patient for clotting disorders and platelet dysfunction was remarkable for clopidogrel resistance.
The touch screen is menu driven with six tabs across the top. The active screen tab will appear in black. There are 2 versions of the system monitor: Older version monochrome screen (one color) Newer version multicolor screen If the system monitor has been upgraded with the HM II software, when the system monitor is turned on the HeartMate logo screen with software version will appear. Once the system controller is connected to the PBU cable, the appropriate software will be displayed, ie HM II clinical screen or XVE clinical screen.
The clinical screen is the default screen and displays the primary operating parameters. The system monitor will automatically return to the clinical screen should there be 60 seconds of inactivity on any other screen. Information is updated every second. Pump flow display can be turned off by touching the flow box and back on by touching it again. Pump flow will not be displayed for speeds set below 8,000 rpm. Pump flow is an estimate based on pump speed and amount of power being provided to the pump. Pump speed is displayed in revolutions per minute (rpm) – under normal conditions, it will match the speed setpoint + 100 rpm. Speed setpoint range is 6,000 – 15,000 rpm. If pump is disconnected or becomes disconnected, box will display pump disconnected and banner turns red. If pump is stopped, box will display ----. Pulse index range is 0.0 to 10.0. If pump is off or becomes disconnected, -.- will be displayed. Pump Power is displayed in Watts with a range of 0.0 to 25.5. Alarm messages - the 2 highest active alarm messages will be displayed below the operating mode. Hazard messages are black upper case letters in a flashing red banner and advisories are upper and lower case letters in a non-flashing yellow banner (except Warning Low Speed Operation which flashes). If more than 2 alarms are active, + appears on right side in the 2 nd banner. Go to alarms screen to view all active alarms. Two command buttons appear during certain conditions: Pump start button appears on the lower left corner when the pump has stopped. Silence alarm button appears on the lower right corner with any active audible alarms. Pressing silences the hazards for 2 minutes and advisories for 4 hours (same as system controller).
The system controller has 2 controller boards, one for the primary system operation and one for complete backup system operation in the event the primary system malfunctions or becomes inoperable. The system controller power leads provide equal power to the pump. The white power lead contains a data link cable that transmits data from the controller to the System Monitor or Display Module when connected to the PBU. To save data &/or waveforms to a card: White lead - download data to the card Black lead – save waveform (current trace) So as long as the cables are intact, transferring the event recorder should be ok with just the white. But for the complete waveform capture data both cables are required.
But like any implanted device, it is best to not place pads directly over it.
If family members or aide’s on scene, utilize their expertise to help mitigate any problem there might be with equipment. Contact medical control.
Counterpulsation is the key to proper use of the IAB with the goal of ….
Pulsatile – Uses pneumatics to circulate blood. These are loud devices and ventricular rate can be assessed by simply listening to the machine. These patients will have a pulse and blood pressure although it may be faint. Older first generation type models. Non-Pulsatile – Continuous flow that work with an impeller similar to a fire pump. These devices are quiet and cannot be heard outside the patient. Auscultation of the apex of the left ventricle will produce a smooth humming sound to ensure device is functioning. Patients will have weak or no pulses. The patient will additionally may have narrow pulse pressures and often difficult to obtain with automatic BP monitors.
Has two posterior pads and one pad that lies anterior just below the left nipple. - These are dry pads that release a conductive gel when a shock is imminent - Patients who have been shocked by these devices will have blue gel covering their torso A series of four electrodes located in the harness continually monitor patient rhythms The control module on the hip has a battery located in it that slides in. The module also has controls the operator can manipulate to prevent a shock from happening should the patient be awake. This would prevent an unneeded shock from occurring. The module itself records continuously, should a shock occur, bring the AED with you to the hospital so a cardiologist can analyze the data.
Essentially it is used to treat anyone who is at risk for sudden cardiac arrest but is not able to have an ICD placed. Some MI patients must wait 30 days or so before an ICD and be implanted. These patients can now have protection from SCA with the lifevest.
Over 25,000 patients nationally have utilized the lifevest Of those 25,000 – there have been 358 saves *LifeVest has a 98% first shock success rate. In Dupage county there are approx. 20-30 users of the lifevest CDH is large distributor There has been a 200+% increase in usage in the past year.
Treat these patients as if they had a normal AED on. Allow the LifeVest to finish it’s cycle before manipulating the defibrillator. The device will alarm to advise of when a shock will be delivered. A two tone siren alarm followed by a voice “Press response buttons to delay treatment.” “Electrical shock possible, Do Not Touch Patient.” “Bystanders do not interfere.” Once the cycle has finished and the patient has been shocked, it will take approximately 45 seconds for another shock to be delivered. In this time frame we can remove the patient from the lifevest and place onto provider monitors.
The only way to completely shut down the lifevest is to remove the battery. The battery is located in the control module worn at the waist. Simply remove the module from the case and there will be a battery that slides in and out. Release the locking mechanism to remove the battery.
In the front of the vest on the lower abdomen, there is a clasp that is easily undone. The vest can now be slid off the patients shoulders. This allows us to have access to the patient to place our own pads on to assist in monitoring and defibrillation. Try to avoid cutting any part of the vest itself. And there is no need to remove the entire garment. Just enough to give yourself access to the apex and anterior chest of the patient. Bring AED with you to the hospital for data acquisition and analysis. Questions?
LVAD – Sends blood from the left ventricle to the aorta RVAD – Sends blood from the right ventricle to the pulmonary artery Bi-VAD – Pumps from both ventricles into both the pulmonary artery and the aorta.
Statistics are ANNUAL data. Becoming much more common. Statistically, there are approximately 45 VAD’s being utilized by patients in the chicagoland area.
Bridge to Transplant – For patient awaiting a heart transplant. This can be utilized to help the patient survive for years while waiting for a heart transplant Bridge to Recovery – The VAD is used on these patients to essentially take the workload off the heart so it can recover. Temporary use of an external VAD device is placed on the lower leg. Connected to the circulatory system via cannulae inserted into the arteries in the groin area. AKA TandemHeart (as pictured). These patients will not be mobile while under the care of the Tandemheart type VAD. Destination Therapy – These are patients who are not candidates for heart transplants but will die without one. The VAD can add a few more quality years until they pass. Again the applicability of VAD devices is becoming more common. Therefore, their use is on the rise.
Watch for skin parameters in these patients. Normal vitals may be difficult to obtain including pulse ox levels. Patients skin condition can tell a lot about his or her cardiac output. Look for signs and symptoms of heart failure. Contact medical control as early as possible!
To assess, auscultate with a stethoscope just inferior to the left nipple. You should hear a distinct humming sound which ensures the pump is operating. If pump operation failure detected, check the main percutaneous lead to the body to make sure it is plugged into the control module. Additionally, check to be sure battery levels are adequate on the module as well. If the pulse is obtainable.
Patients should have an emergency contact sheet for a VAD representative/coordinator for their particular VAD device. If able, call the emergency contact number for assistance.
But like any implanted device, it is best to not place pads directly over it.
If family members or aide’s on scene, utilize their expertise to help mitigate any problem there might be with equipment. Contact medical control.
Hand pump utilized on some models in case of electronic pump failure.