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 InfectionDevice‐related (i.e., endocarditis)Device‐specific (i.e., driveline and VAD pump pocket infection)Non‐LVAD infection (i.e., urinary tract infection, pneumonia)

 Bleeding (i.e., gastrointestinal bleeding)

 Cerebrovascular pathology: ischemic or hemorrhagic stroke

 Hemolysis

 New right ventricular failure

 Dysrhythmia

 Aortic regurgitation

Device‐specific problems can manifest as device failure (fortunately rare) or from battery or cable connection issues. Suction events can occur when there is not enough volume in the left ventricle to support the speed of the pump. This causes the intake cannula to collapse and subsequent ventricular arrhythmias [11]. LVADs in place for a long time can become dislodged, resulting in incomplete left ventricle emptying, right ventricular failure, and arrhythmias. LVADs may also have thrombotic complications, causing problems ranging from dyspnea to cardiogenic shock [18, 19].

While EMS clinician interactions with LVAD patients may be infrequent, these patients are high acuity and tend to have high rates of hospital admission [20]. It is beneficial for EMS systems to be aware of LVAD patients in their service areas, and have device reference cards and VAD specialist contact information accessible [21]. Hospital policies may indicate that a VAD specialist be sent to the scene to evaluate the device in the event of a problem. This situation could then result in a delay in patient transport while the VAD specialist is en route. If the patient is having a time‐sensitive medical issue not related to the device, a medical oversight decision may need to be made regarding transport. For example, perhaps a portable LVAD patient is having an acute stroke or GI bleed and no LVAD issues, but the EMS crew is not familiar with the LVAD. The medical oversight physician will need to weigh the risks of delay of transport while waiting on the VAD specialist to arrive versus the risk of an LVAD complication during the EMS transport.

The LVAD patient in distress might be having an issue with the device, an exacerbation of the underlying cardiac disease, or an unrelated medical event. The initial EMS assessment should be to determine if the issue is LVAD‐related or not (Figure 11.3). If the event does not seem to be LVAD‐related, then local protocols or medical oversight should be consulted for further guidance. The next step is to determine the type of LVAD involved. The patient and caregiver should have device information available. This information should include whether the patient can receive electrical therapy and whether or not CPR can be performed. Obviously, these questions need immediate answers [11, 21].

EMS personnel must determine if the device provides pulsatile flow or continuous flow. A patient with a pulsatile flow device should have a palpable pulse and blood pressure. Pulsatile‐pump LVAD failure requires the use of a hand pump to produce blood flow. A patient with a continuous‐flow device will have no detectable pulse. A functioning pump should make a humming sound on auscultation [11]. In the event of device malfunction, the LVAD should generate a series of auditory and visual alarms. These alarms will be device‐ and manufacturer‐specific. The patient, caregiver, and device literature should be used to determine alarm causes. Power alarms may be triggered by low voltage in the batteries, necessitating battery changes, or, in the case of a pulsatile device power failure, hand pumping. Low‐flow pump alarms most likely result from hypovolemia, which indicate the need for IV fluids or blood products. Other alarms may indicate cable disconnections that require troubleshooting. Transport should not be delayed to perform these interventions [11].

Figure 11.3 Emergency assessment of a patient with an LVAD.

Patients with continuous‐flow devices may not have reliable pulse oximetry readings due to low pulse pressures. As noted, a continuous‐flow device will not produce a palpable pulse or a measureable blood pressure. The EMS clinician will need to use other signs to assess perfusion, such as skin color, absence or presence of diaphoresis, and mental status changes. The patient should be placed on a cardiac monitor, and a 12‐lead ECG should be performed if possible, though the LVAD will create electrical noise on the ECG tracing. LVAD patients should also be exposed to examine for cable disconnections. The driveline skin site should not be routinely examined unless absolutely necessary, due to risk of infection. Clothes should not be cut with shears as there is risk of cutting the cables with disastrous results. For the same reasons, the patient should be moved carefully to prevent dislodgment. Patients showing signs and symptoms of another illness, such as stroke, should be assessed in the usual fashion, regardless of the assist device.

Patients with evidence of hemodynamic compromise or hypoperfusion should have large‐bore IV access, and be volume resuscitated. Vasopressors are not generally a good initial therapy, as many problems are volume‐related, and vasopressors will increase afterload, which can worsen pump flow [11].

Arrhythmias should only be treated if they are symptomatic. An LVAD patient with full left ventricle support may be able to tolerate ventricular tachycardia or fibrillation. If the arrhythmia requires treatment, the usual therapies can be used for rate control and rhythm conversion. The patient can also receive electrical therapy [11]. Defibrillator pads should not be placed over the device. Some devices may require that the system controller cables be disconnected prior to defibrillation to prevent damage to the electronics. The patient should also be examined for the presence of an implantable cardioverter defibrillator (ICD), which should provide the appropriate treatment in the event of ventricular arrhythmia [22].

The decision of when to perform CPR can be a major conundrum in treating these patients. Knowledge of the device type and function is crucial. Patients with first‐generation LVADs producing pulsatile flow should not receive chest compressions. Instead the hand pump should be used. Second‐generation and later continuous‐flow devices will not have a hand pump. Chest compressions carry the risk that they may dislodge the device, resulting in exsanguination and death. On the other hand, if the LVAD is not pumping, the underlying left ventricle will not have the ability to maintain perfusion of organ systems. Patient survival is not likely. Lack of compressions may also result in a thrombus formation in the pump, resulting in obstruction to pump flow, and potential downstream embolic events. Awareness by EMS clinicians of the patient’s advanced directives regarding resuscitation may be important, as these patients have chronic severe disease. Ideally, device information, patient wishes and treatment plans, and contact information should be prepared prior to initial discharge from the hospital. In the event of an EMS contact with a patient who is hypoperfused and has a nonfunctioning pump, an attempt may be made to contact the LVAD coordinator for further recommendations. If the coordinator cannot be reached, and the patient is to be resuscitated, compressions should be started and transport initiated per local protocols [11].

The LVAD patient should be transported to the hospital that placed the device if possible. These hospitals are usually tertiary care centers and should be capable of managing not only LVAD complications but also other issues, such as stroke or GI bleeding. If there are distance issues, air medical transport should be considered. This can shorten transit time and also provide critical care services. Regardless of transport mode, the LVAD patient should be transported with all device equipment, batteries, controllers, documentation, and caregivers (if possible).