Patient Treatment and Transport Study Guide for the EMT Test

Cardiovascular and Circulatory Management: Part 1

Dealing with Heart Surgeries and Cardiac Assistive Devices

The current healthcare environment has many advanced treatments, surgeries, and technological devices that assist the patients with heart conditions. Knowledge of these devices and how they assist the patient is important for the EMT.

Implantable Cardiac Defibrillator (ICD)

A physician places the ICD device in the chest or abdominal area. It is used for patients with high-risk arrhythmias that have potential for sudden cardiac arrest. It works by delivering shocks to the heart when life-threatening arrhythmias occur.

Here are concepts to know:

basic knowledge of the cardiac electrical system—This is the body’s built-in wiring that controls the heart’s rhythm and ensures coordinated pumping. It starts at the sinoatrial (SA) node, the heart’s pacemaker, which causes the atria to contract. The signal then travels to the atrioventricular (AV) node, allowing the ventricles to fill. Then it moves to the bundle of His, through the right and left bundle branches, and into the Purkinje fibers, triggering a strong, organized ventricular contraction.
how to treat a patient with an ICD—EMT care of ICD patients is mainly supportive and focuses on standard assessment. If the patient reports being shocked, appears anxious, or is experiencing chest pain, the EMT should treat them like a cardiac patient; assess airway, breathing, and circulation; monitor for continued symptoms; and prepare for transport. If the patient becomes unresponsive and pulseless, begin CPR immediately and use the AED as usual.

Pacemaker

A pacemaker is an implanted device that helps regulate the heart rate by sending small electrical impulses through leads attached at the myocardium (heart muscle). Patients with pacemakers should be assessed and treated according to their signs and symptoms. If the patient becomes pulseless, begin CPR and use an AED as indicated. Avoid placing AED pads directly over the pacemaker.

Defibrillator Vest

This device is a vest worn externally under clothing. It has a defibrillator, monitor, and voice system. The device delivers high-energy shocks similar to an AED.

Here is a concept to know:

precautions with a patient who has a defibrillator vest—do not remove the vest unless absolutely necessary; be aware that the vest can deliver a shock (do not touch the patient when this happens); remove the vest to perform CPR and apply the AED as usual; avoid getting the vest wet; do not place AED pads or monitors on the vest; expect sounds or alarms

If blue gel is seen under the defibrillator vest pads, the device has already delivered at least one shock. Do not touch the patient while the vest is preparing to shock. Follow local protocols to remove the vest if CPR and AED placement are needed. Continue resuscitation without any delays.

Left Ventricular Assist Device

Patients with severe heart failure or those with a need for additional support to pump blood may have this type of device. The left ventricular assist device (LVAD) supports the pumping function of the left ventricle. The device may be set for intermittent pumping or pulsing, similar to the way the heart functions. It may also be a continuous pumping, which impacts the ability to palpate the patient’s pulses.

Here is a concept to know:

difference between pulsatile and continuous LVAD—Pulsatile LVADs are older devices that mimic the natural heartbeat by pumping blood in pulses. Patients using these will have a palpable pulse and measurable blood pressure. These devices are larger, louder, and less common today. Continuous-flow LVADs are modern devices that pump blood in a steady, continuous stream without a traditional heartbeat. Typically, there is no pulse or blood pressure.

Automated External Defibrillator

The defibrillation process is done in conjunction with and in coordination with persons performing CPR, giving rotating breaks when possible to prevent exhaustion. The AED is used on the unresponsive patient as soon as it is available at the scene. The AED will direct the process for delivering shocks. After each defibrillation, CPR will continue, starting with compressions.

Here are some concepts to know:

how to coordinate CPR and defibrillation—Minimize interruptions in chest compressions as much as possible while preparing and applying the AED. Compressions should be paused only briefly, just long enough for the device to be applied and the rhythm analyzed. If a shock is advised, everyone must be clear of the patient (no touching) while the shock is delivered. Immediately following delivery, CPR should be resumed. This process will be repeated in 2 minutes after five cycles of CPR. The goal should always be to keep pauses in compressions under 2 minutes.
steps for using an AED, ROSC—Ensure the scene is safe; assess the patient for responsiveness, pulse, and breathing (call for help or start CPR); turn on the AED; expose the chest; attach pads; allow analysis; shock if advised; resume CPR immediately; and repeat. Once a patient regains a pulse or shows signs of circulation, the EMT should check for responsiveness and breathing, maintain the airway and provide oxygen as necessary, monitor vital signs closely, position the patient appropriately, prepare for transport, and continue monitoring.

The AED is a computerized, interactive, semi-automated device. The invention and wide distribution and use of AEDs have supported the increased survival rate for cardiac emergencies. The device works to monitor electrical impulses from the heart through electrodes and deliver appropriate shock based on certain and often fatal arrhythmias. AEDs are designed to be easy-to-use so even non-medical personnel can use them in the event of a cardiac emergency.

Here are some concepts to know:

five links in the chain of survival—immediate recognition of cardiac arrest and activation of EMS, early CPR, rapid defibrillation, effective advanced life support, and post-cardiac-arrest care
Electrocardiogram (ECG)—a recording of the heart’s electrical activity obtained through electrodes placed on the patient’s skin. AEDs analyze the heart’s electrical activity to determine whether a shock is advised, while ECGs and cardiac monitors display the heart’s rhythm for assessment and monitoring.
Artifact—interference on an ECG tracing that does not come from the heart’s electrical activity. Common causes may include patient movement, poor electrode contact, incorrect lead placement, or a loose monitor connection. Artifacts can make it more difficult to accurately interpret the heart rhythm.

When to Use a Defibrillator

As a general rule, the defibrillator should be used on all unresponsive patients without palpable pulses. The defibrillator will monitor and analyze if a shock is needed at any point during the time care is being provided. Always follow the defibrillator’s instructions before delivering a shock.

Here are concepts to know:

general function and advantages of the AED—General functions include analysis of heart rhythm, shock delivery advisement, rescuer guidance, and event data recording. Some advantages of the AED include rapid defibrillation, simplicity of use, reduction of human error, portability and accessibility, and increased survival rates.
when to avoid use of the defibrillator and rationale—The only time use of a defibrillator should be avoided is if its use is not indicated (patient has a pulse), or the scene is unsafe. A defibrillator should always be used to treat patients in cardiac arrest if available. Instances where caution should be used include patients submerged in water or that are in contact with metal materials; in these instances, the patient should first be dried/moved before they are defibrillated in an effort to avoid electrical conduction.
bradycardia—a heart rate that is slower than normal, less than 60 beats per minute for an adult
tachycardia—a heart rate that is faster than normal, greater than 100 beats per minute for an adult

Using a Defibrillator and Resuscitation

Many communities have provisions for laypersons to be trained to provide CPR. This has many benefits and often plays a large part in positive patient outcomes. The EMT may encounter patients in whom CPR is already in progress, but should be ready to take over care when they arrive on the scene. AEDs should be used on patients for whom CPR is not producing a pulse and/or the patient is unresponsive. When applying the AED pads, place one pad on the upper right chest below the collarbone and the other on the left side of the chest, approximately 2–3 inches below the armpit. Follow the placement diagram shown on the AED pads.

Here are concepts to know:

asystole—This is a cardiac rhythm characterized by a complete absence of electrical activity in the heart, resulting in no pulse or perfusion; it resembles a flat line on an EKG.
pulseless electrical activity (PEA)—This is a non-shockable cardiac arrest rhythm in which organized electrical activity may be present, but the heart is not producing an effective pulse.
use of AED with active CPR—The AED should be applied as soon as it becomes available with minimal interruption in CPR. Once the AED has been turned on, applied, and has begun analyzing, CPR should be paused briefly to allow the AED to obtain an accurate reading. After analysis, if no shock is advised, chest compressions should be immediately resumed. If a shock is advised, the patient should remain untouched until the shock is delivered, after which chest compressions should be immediately resumed.

After Defibrillation

Post-defibrillation care includes three basic scenarios: (1) the patient has regained a pulse; (2) there is no pulse and the AED recommends shock; and (3) there is no pulse and the AED does not recommend shock. Knowing your jurisdiction policies and procedures in various scenarios is important.

Here is a concept to know:

treating a patient with no pulse and no AED shock recommended— Treatment for this patient consists of high-quality CPR, including chest compressions and ventilations until ROSC is achieved, the patient is transported, or the patient is pronounced dead by a higher level of care.

Arrest During Transport

During transport, the patient should be closely monitored. If, during the course of the transport, the patient does not have a palpable pulse or a conscious patient becomes unconscious, the process for care delivery must resume according to the best practice recommendations within your jurisdiction and ALS guidelines.

Here is a concept to know:

resuming or starting CPR during transport—Performing CPR while in transport poses a significant risk to providers; however, it may be necessary if the patient is in cardiac arrest. Providers may pull over safely to initiate and perform resuscitation efforts if needed. Mechanical CPR devices may also be used if available to minimize risk.

Defibrillator Maintenance

The emergency team is responsible for the proper use and maintenance of the AED on its rig. Preventive maintenance (PM) and quality checks should be a part of the emergency equipment maintenance regime and should always include the AED. Follow your jurisdiction and/or machine handbook to ensure everyone is trained on the proper use and maintenance of all relevant medical equipment.

Here are concepts to know:

legal risks with an AED—There is very minimal, if any, risk associated with use of an AED, as it is a life-saving tool. There are also laws in place, such as the Good Samaritan law, which protect responders from liability. EMTs should, however, exercise caution and avoid using the AED on patients with valid DNR/advanced directive orders in place, as this could lead to liability and legal issues.
ways to ensure the function of an AED— Proper function of the AED can often be indicated by a light or marker identifying that it is ready for use; however, most AEDs can also be put through a function test, which performs checks and tests quickly to ensure the AED is working properly. Manufacturer specifications should be followed for each individual AED when determining its functionality status.
reporting manufacturer’s malfunction of an AED—Any issues or essential events encountered while using an AED should be reported to department heads; however, they should also be taken directly to the specific AED’s manufacturer to collect data and prevent further incidents from occurring.

Defibrillator Use for Children

AED and manual defibrillators are safe to use with children. There are considerations for the type of device, pads, and a dose-attenuating system (energy reducer) for infants under one year of age, and for those up to eight years of age. Seek best practice recommendations from the American Heart Association.

Here are concepts to know:

manual defibrillator—a method used by advanced providers where the clinician interprets the cardiac rhythm on the cardiac monitor and manually selects the energy level before delivering the shock
pediatric dose attenuator—device used with an AED to reduce the energy of the shock so it is safe for infants and small children (typically under 8 years old or less than 55 pounds)
options in the absence of a pediatric defibrillator—If pediatric modification devices, such as pads or a dose attenuator, are not available, adult AED pads and energy should still be utilized. Alternate pad placement may be necessary for smaller children (anterior/posterior).

Special Situations

There are always variables that fall outside of a “normal” defibrillation situation. Here, we will discuss three that require additional knowledge, especially concerning safety.

Pacemakers and Implanted Defibrillators—Patients with chronic heart conditions may have implanted or internal devices. Avoid placing the AED pads directly over these devices. If a device is located where the AED pad would normally be placed, simply put the AED pad directly below the device. The anterior or posterior pad position may also be used.
Wet Patients—The scene size-up must include observation of the environment related to damp/wet areas around the patient. Water acts as a conductor of electricity, and electronics, including the AED, should not be used in water. This is for both the safety of the patient as well as the safety of the emergency response team. If the patient is lying in a large amount of water, move them out of the water and dry the skin prior to attaching the AED pads.
Transdermal Patches—Patients may wear medication patches for various reasons. Always use a gloved hand to remove any patches that may interfere with lead or AED pad placement, and wipe the area clean and dry to free it of gel or residue before application.

Here is a concept to know:

alternative AED pad placements—Anterior-posterior pad placement can be utilized as an alternative to traditional placement. This includes placing one pad on the center of the chest over the sternum and the other on the back between the shoulder blades.

Spontaneous Circulation Return

Return of spontaneous circulation (ROSC) in a patient who may not have had palpable pulses is a positive sign. This means that the patient has regained sufficient blood flow to the body after a cardiac arrest.

Here is a concept to know:

how to handle—The priority of managing a ROSC patient should be to support circulation and prevent rearrest. The EMT should stop compressions; reassess airway, breathing, and circulation; and obtain a pulse and respiratory rate. Provide high-flow oxygen and assist ventilations as needed. Monitor mental status, skin signs, and blood pressure. Watch closely for signs of rearrest and promptly transport the patient to the hospital.