Clinical Medical AssistingChapter 13: Circulatory System

Objectives• Identify combining word forms of the cardiovascular system

and their role for the formation of medical terms

• Define the structures and functions of the circulatory system

• Identify common diseases, diagnostic procedures, and treatments related to the circulatory system

• List abbreviations related to the circulatory system

• Explain the principle of the vacuum tube system

• State the manner in which anticoagulants prevent coagulation

• Explain the three skill sets used in collecting blood specimens

• Explain the importance of correct patient identification; complete specimen labeling; and proper handling, storage, and delivery of the specimen

• Explain how to handle the various reactions a patient might have to venipuncture

• Follow the circulation of blood through the heart starting at the vena cava

Objectives (con’t)

Chapter OverviewThe circulatory system, also called the cardiovascular system, is composed of the heart and blood vessels. Circulation consists of two separate cycles: pulmonary circulation, which transports blood between the lungs and the heart so gas exchange can occur, and systemic circulation, which transports blood between the heart and the rest of the body so the exchange of nutrients, metabolites, and hormones can occur.

Structure and Function of the Circulatory System

The primary function of the circulatory system is to propel blood through the body.

Heart

A muscle that is about the size of a fist and pumps blood.

ArteriesCarry blood containing oxygen and nutrients away from the heart to cells throughout the body

Veins

Carry blood that lacks oxygen back to the heart

Diseases and Disorders of the Circulatory System

A leading cause of disability and death each year

Arrhythmias

Variation in the normal heart rate or rhythm

Signs and Symptoms of Arrhythmias

Abnormal contraction and electrical conduction of the heart lead to conditions.

Congestive Heart Failure

The heart is unable to pump enough blood to meet the body’s needs

Signs and Symptoms of Heart Failure

Increased shortness of breath during formerly comfortable activities

Hyperlipidemia

Elevated levels of lipoproteins, triglycerides, and cholesterol

Signs and Symptoms of Hyperlipidemia

Diagnosis of hyperlipidemia requires a blood test.

HypertensionBlood pressure is the product of cardiac output and total peripheral resistance.

Signs and Symptoms of Hypertension

Elevated blood pressure can lead to devastating and disabling consequences.

Ischemic Heart Disease

A condition in which the heart muscles receive a decreased supply of blood

Signs and Symptoms of Ischemic Heart Disease

Angina is the hallmark symptom of ischemic heart disease.

Myocardial Infarction

Commonly known as a heart attack

Signs and Symptoms of Myocardial Infarction

Chest pain is the hallmark symptom

Stroke

Occurs when oxygen supply to an area of the brain is interrupted

Signs and Symptoms of Stroke

Develop suddenly and include a headache

Peripheral Artery Disease

A manifestation of the narrowing of the blood vessels in the extremities due to atherosclerosis

Signs and Symptoms of Peripheral Artery Disease

The first symptoms to appear are usually pain or discomfort in the legs.

Venous Thromboembolism

A thrombus may result from abnormal coagulation, altered blood flow, increased platelet adhesion, or damaged blood vessels.

Signs and Symptoms of Venous Thromboembolism

Many blood clots exist without symptoms.

Diagnostic and Treatment-Related Procedures of the Circulatory System

More than 60% of cardiac deaths occur with no prior history of heart disease and, often, few or no symptoms.

Cardiovascular History

A detailed medical history is the cornerstone of cardiovascular evaluation.

Physical ExaminationA component of a global patient evaluation includes a physical assessment of all body systems.

Testing Modalities

Chest radiography is often the first cardiovascular test performed after the initial history and physical.

Helping with Radiography

The Medical Assistant may help with chest radiography, and so must learn appropriate techniques.

Bipolar LeadsThe first three leads are standard or bipolar leads, because they connect two electrodes.

Augmented Leads

The second three leads are augmented leads and also measure the voltage difference between two points.

Precordial Leads

Monitor only one electrode and a point within the heart

Electrocardiogram

The electrocardiogram (ECG or EKG) measures the heart’s electrical activity through electrodes placed on the surface of the body.

Stress TestA stress test, also known as exercise electrocardiography, is used to assess cardiovascular disease by evaluating the circulatory system’s ability to respond to physiologic changes.

Echocardiogram

An echocardiogram (ECHO) uses sound waves to create a moving picture of the heart.

Cardiac Catheterization

The process of passing a thin tube (catheter) through the blood vessels leading to the heart

Blood Tests

Laboratory blood tests are performed on whole blood, serum, or plasma

Skills for the Medical Assistant

Your confidence will ease the patient’s fears and allow for safe and accurate testing.

Performing Venipuncture by Syringe

When a blood sample is needed from a small or fragile vein, blood can be collected using a needle and syringe.

Performing Venipuncture by Vacuum Tube System

The vacuum tube system for blood collection is the preferred method for blood collection because it is simple and requires the fewest steps.

Performing Venipuncture by Butterfly Needle System

A butterfly needle system is used to perform a venipuncture in small, fragile veins or those that are difficult to see or access.

Performing Capillary Puncture

A skin puncture using a sterile lancet is used to collect a small amount of capillary blood.

Performing a 12-Lead ECG

An ECG is performed to obtain a graphical representation of the electrical activity of the heart.

Performing an Ambulatory ECG

Patients who experience irregular or intermittent chest pain or unusual symptoms, but who still have normal standard ECG results, may require ambulatory ECG monitoring.

SummaryThe circulatory system is composed of the heart and the blood vessels (arteries, veins, and capillaries) that circulate blood through the body. Pulmonary circulation transports blood from the heart to the lungs so gas exchange can occur, and systemic circulation transports blood from the heart to the rest of the body so the exchange of nutrients, metabolites, and hormones can occur.

Summary (con’t)The heart is a double pump. It contains two collecting vessels (atria) and two distributing chambers (ventricles). Four valves in the heart direct the unidirectional flow of blood through its chambers.

Blood flows in a continuous loop around the body. Each beat of the heart is a series of integrated, coordinated events that lead to the contraction and relaxation of the heart’s atria and ventricles that propel the blood through the body. The heart contracts as a result of an electrical impulse initiated in the sinoatrial node, known as the heart’s pacemaker.

Summary (con’t)As a medical assistant, you will have the opportunity to assist in procedures related to the diagnosis and evaluation of disorders of the circulatory system, including venipuncture by a variety of methods, capillary puncture, and performing an ECG. You should be calm, confident, and professional throughout the procedures to maintain the safety and comfort of the patient. You also have the opportunity to promote healthy lifestyle choices to patients and encourage lifestyle modifications to manage risk factors for cardiovascular diseases and complications.