Primary Assessment Study Guide for the EMT Test

Circulation

Many emergencies involve problems with the heart and its functions, which include circulation. In assessing circulation, you will be dealing with both the heart and the circulatory system and you’ll need to know both the appropriate terms and actions to make the most of the few minutes you may have to save a life. Cardiac assessment is critical no matter the environment. In an emergency situation, accuracy, timing of treatment, and medication regimens are extremely important for the best patient outcomes.

Cardiac Anatomy and Physiology

The cardiovascular system consists of arteries, veins, capillaries, and the heart. Knowledge of this system and how it works, including its potential dysfunctions and diseases, is critical to patient management in emergencies.

Heart Function

The primary function of the cardiovascular system is to ensure the flow of oxygenated blood throughout the body. Using the atrium, ventricles, and aorta, the system is precise in delivery. The veins carry blood to the heart and the arteries carry blood from the heart throughout the body. In the process of this delivery, by-products are carried to the systems that function to rid the body of waste, such as the urinary or digestive systems.

Here are some terms to know:

• atria—the two upper chambers of the heart that receive blood and pump it to the ventricles

• ventricles—the two lower chambers of the heart that receive blood from the atria

• aorta—the main artery in the body

• parts of the heart—includes the four main chambers, several valves, and other features

• blood flow pathway—the path blood takes through the body, including its path through the various parts of the heart

• automaticity—the ability of cardiac tissue to automatically set the pace of the heart through electrical impulses

• autonomic nervous system—controls involuntary body functions, such as breathing and heart rate

• sympathetic nervous system—part of the autonomic nervous system; controls the body’s “fight or flight” response to stressful situations

• parasympathetic nervous system—functions to calm and relax the body after stressful events

Circulation

Circulation is the system of flow from the heart to the other tissues of the body and back again. For the system to function optimally, there must be an adequate volume of blood, patent valves, and functional vessels that dilate to allow blood flow.

Here are some terms to know:

• myocardium—thick, muscular, middle layer of the heart wall

• Chordae tendineae—thin, cord-like bands that anchor the heart’s atrioventricular valves to the papillary muscles, while keeping the valves from flipping backward, or inverting, when the ventricles contract

• stroke volume—the amount of blood the heart pumps out of the left ventricle with each heartbeat

• dilation—widening or opening of a blood vessel

• coronary arteries—blood vessels that supply oxygenated blood to the heart muscle (myocardium)

• pulmonary artery—the artery that carries oxygen-poor blood from the right ventricle to the lungs for oxygenation

• aortic valve—one-way valve in the heart, between the ventricle and aorta, allowing for oxygenated blood to flow from the heart to the body

• cardiac output—amount of blood the heart pumps in one minute; can be calculated by multiplying the heart rate by stroke volume

Review of the Cardiovascular System

The cardiovascular system’s main job is to maintain adequate blood flow, pressure, and supply throughout the body. The word system is key, as there is more to it than the heart; the system also includes veins, capillaries, and arteries.

Here are some terms to know:

• function and location of the heart—The heart pumps blood throughout the body and is located in the thoracic cavity between the lungs and mediastinum.

• arteries—blood vessels that carry blood away from the heart

• capillaries—tiny, thin blood vessels that connect arteries to veins

• the three parts of the cardiovascular system—These three parts are:

  • heart—the muscular pump that moves blood through the body

  • blood vessels—the network of tubes that carry blood (arteries, veins, capillaries)

  • blood—the fluid that transports oxygen, nutrients, hormones, and waste products

• aorta—largest artery in the body; carries oxygenated blood from the left ventricle to the heart

• venules—small blood vessels that carry blood from the capillaries to the veins

• veins—blood vessels that carry blood toward the heart

• arterioles—small blood vessels that branch off from arteries and lead to capillaries

• left ventricle—the lower left chamber of the heart pumps oxygen-rich blood into the aorta and out to the body, containing the thickest muscle wall of the heart chambers

• right ventricle—the lower right chamber of the heart that pumps oxygen-poor blood to the lungs for oxygenation

Pathophysiology and Perfusion

The Merriam-Webster medical dictionary describes perfusion as “the pumping of fluid through an organ or tissues.” You need to understand the importance of adequate perfusion. Your knowledge needs to include the symptoms and disease processes that impact organs and systems when there is not adequate perfusion.

Here are some concepts to know:

• perfusion as it relates to blood flow—Perfusion is the process of blood delivering oxygen to the body’s tissues. When blood flow is decreased, so is perfusion, as that oxygenated blood is unable to reach the tissue adequately.

• inadequate perfusion impact to critical organs and systems—When perfusion is decreased and oxygenated blood cannot adequately flow to body tissue, critical organ systems are at risk of failure.

• time frames for death/damage to an organ or system without adequate perfusion—No organ or body system can function properly or survive very long without being perfused. Some can outlast others; the longer-lasting tissues include the skin and muscle. The skin can tolerate several hours of reduced perfusion, muscles and tissues usually two to four hours, kidneys less than 90 minutes, and the brain can only last a few minutes (generally, four to six minutes).

Chest Pain or Discomfort

The presence of chest pain and/or discomfort is a sign for further assessment and immediate intervention. Not all chest pain is related to a cardiac event; however, a timely response is imperative if it is cardiac-related.

Basic Treatment

The fundamental treatment regimens for chest pain include: positioning of the patient, basic comfort measures, removal or adjustments to clothing, and oxygen support via an appropriate mechanism for the condition.

Here are concepts to know:

• oxygen titration—adjusting the amount of oxygen given to a patient to reach a safe and effective oxygen level

• mechanisms for oxygen delivery—methods used to provide supplemental oxygen to patients (nasal cannula, simple mask, non-rebreather mask, bag valve mask, venturi mask)

• preventive ASA (aspirin) usage and doses—often used to reduce the risk of heart attack in patients experiencing chest pain/cardiac problems; the dose given by EMTs is four 81mg tablets for a total of 324mg

Using Nitroglycerin

Many patients who are at risk and those who have had previous cardiovascular episodes have prescriptions for nitroglycerin. The maximum dosage frequency and time frame for nitroglycerin administration for a chest-pain incident is three (3) doses every 5 minutes. There are important key points in its administration: be sure to know the nitroglycerin expiration date, the potency, the prescription rights, any contamination issues, and the handling steps of the pills and patches.

Here are concepts to know:

• nitroglycerin dosage—A single dose of nitroglycerin is 0.4mg; this dose can be given every 5 minutes up to three (3) times by the EMT per episode, as long as symptoms persist.

• indications and contraindications—Nitroglycerin is indicated in conscious patients who are able to follow commands, those with a prescription for nitroglycerin, and those experiencing atraumatic chest pain believed to be cardiac in nature. Contraindications include a systolic blood pressure below 90–100mmHg, recent use of phosphodiesterase inhibitors within 24–48 hours, a known allergy to nitroglycerin, or head trauma/increased ICP.

• steps and precautions when administering and handling nitroglycerin—Nitroglycerin is administered sublingually; therefore, the EMT should place the medication under the patient’s tongue and allow for absorption through the mucus membranes. The EMT should warn the patient that they may feel a strange sensation in their mouth or develop a headache. EMTs should administer nitro tabs/paste with care, utilizing proper PPE, as it is a transdermal medication and can absorb through the skin of those administering it.

Cardiac Care and Age Range

Emergency care for patients with cardiac concerns is critical. Procedures must be followed and may need to be tweaked based on the individual’s age and unique healthcare needs. For example, a pediatric patient with a history of heart disease typically has congenital defects that would require a slightly different care approach than the care given to the general pediatric population.

Chest Pain in a Child

Chest pain in a child is typically a benign and self-limiting condition related to an acute illness. Respiratory issues, such as choking, are typically the cause of cardiac events in children without a previous cardiac history.

Here is a concept to know:

• congenital—condition or trait a person is born with

Cardiac Issues in Older Patients

Cardiocare for the older patient with a chronic history of cardiac and cardiovascular diseases may differ somewhat from that of a patient with clear arteries.

Here is a concept to know:

• complications common with older patients—Older patients tend to have comorbidities present for which they are taking medications. These conditions may include hypertension, coronary artery disease, heart failure, arrhythmias (afib), etc. These conditions make this particular patient population more susceptible to acute cardiac emergencies like heart attacks, strokes, and even cardiac arrest.