Body Systems II and Common Conditions

This is Unit Four of Medical Assistant Prep. Unit Three ended on one patient whose concerns crossed several systems. This unit adds the remaining systems, the heart, lungs, digestion, kidneys and reproduction, and then the long-term conditions you will see every week. Carry one idea through this lecture. Knowing a condition makes you a better observer, not a decision maker. A constructed morning at the end puts that idea to work in three rooms. By the end you will be able to describe the heart and circulation. To outline breathing, digestion, the urinary tract and reproduction. To name the signs of diabetes and high blood pressure. And to recognize the heart and lung conditions that call for an immediate report.

Six entries on circulation: the heart's chambers and valves, the vessels, pulse and pressure, the pacemaker, and lymph.

Atria receive, ventricles pump.

MAS 076 The Heart's Chambers and Layers

The heart is a muscular organ with four chambers, about the size of a closed fist. The two upper chambers, the atria, receive blood from the veins; the two lower chambers, the ventricles, pump it out; the thick middle layer of the heart wall is the myocardium. The ventricles do the heavy pumping, so their walls are the thickest.

Valves and coronary arteries.

MAS 077 Valves Keep Blood Moving One Way

The heart's valves keep blood flowing in one direction. The tricuspid valve sits on the right between atrium and ventricle, and the mitral valve on the left; semilunar valves guard the exits into the pulmonary trunk and the aorta. The coronary arteries feed the heart muscle itself, which needs a constant supply of oxygen.

Away, exchange, return.

MAS 078 Arteries, Capillaries and Veins

Blood travels from the heart through arteries, exchanges materials in capillaries, and returns through veins. Arteries carry blood away from the heart; capillaries, the smallest vessels, exchange gases, nutrients and wastes with tissues; veins have thinner walls and carry blood back. Veins depend on surrounding muscle activity to push blood home, which matters later for blood draws.

Two measures of one pump.

MAS 079 What Pulse and Blood Pressure Measure

The pulse is the rhythmic expansion of an artery each time a ventricle ejects blood, and blood pressure is the force of blood against the artery walls. Systolic pressure comes from ventricular contraction, diastolic pressure from relaxation; a reading is written systolic over diastolic. Blood pressure varies through the day, so one reading tells less than a pattern.

The heart starts its own beat.

MAS 080 The Heart's Own Pacemaker

The heart starts its own beat: the sinoatrial node fires rhythmic impulses without any signal from the brain. Left alone, the node fires roughly seventy to eighty times a minute; the autonomic nerves then speed the rate up or slow it down to match the body's needs. This electrical system is what an electrocardiogram records, the subject of units twenty-two and twenty-three.

Fluid return and defense.

MAS 081 The Lymphatic System

The lymphatic system returns fluid to the blood and helps defend the body. Lymph nodes, small bean-shaped structures along the lymphatic pathways, filter the lymph through dense clusters of white blood cells before it returns to the bloodstream. Swollen lymph nodes are a finding to report, not one to explain to the patient.

Seven entries on the remaining systems: breathing, the digestive tract and its helpers, the kidneys, and reproduction.

Active in, passive out.

MAS 082 How Breathing Works

Breathing moves air in and out of the lungs by changing pressure inside the chest. Inhaling is active: the diaphragm contracts, the chest enlarges, and air flows in. Exhaling at rest is passive: the diaphragm relaxes and elastic tissue recoils, pushing air out. Labored breathing means that muscles are working hard; report it.

Breaths and spirometry.

MAS 083 Breathing Rate and Lung Volumes

At rest, an average adult takes roughly twelve to fifteen breaths a minute; one breath is one inhalation and one exhalation. A spirometer measures how much air moves in and out of the lungs, and the test is called spirometry. Lung capacity peaks in early adulthood and declines with age, so results are compared with expected values.

The digestive tract.

MAS 084 The Digestive Tract

The digestive tract is one long tube that opens at the mouth and ends at the anus. Its wall has four layers, from the inner mucous lining to the outer covering, with smooth muscle layers that move food along. Accessory organs such as the liver sit outside the tube but are essential to digestion.

Absorbing and ending.

MAS 085 The Small and Large Intestines

The small intestine completes digestion and absorbs nutrients; the large intestine produces no digestive enzymes. The small intestine has three parts, the duodenum, jejunum and ileum, and empties into the large intestine, which ends at the rectum and anus. Stool specimens for testing come from the end of this tract, as unit seventeen covers.

Organs outside the tube.

MAS 086 The Accessory Digestive Organs

The salivary glands, liver, gallbladder and pancreas aid digestion from outside the digestive tube. The liver, the body's largest gland, makes bile and detoxifies; the gallbladder stores bile; the pancreas releases digestive enzymes and, from its islets, hormones. The pancreas works in two systems, digestive and endocrine.

How urine travels.

MAS 087 The Urinary System

The urinary system includes the kidneys, which make urine, the ureters, the bladder and the urethra. Urine travels from each kidney down a ureter to the bladder, a storage reservoir in the pelvis, whose smooth muscle wall contracts to empty it. Urine reflects what the kidneys filter, which is why a simple urine test reveals so much.

Cells and hormones.

MAS 088 The Reproductive Organs

The primary reproductive organs, the testes and the ovaries, produce sperm and eggs and also release hormones. The testes release testosterone; the ovaries release estrogens and progesterone, which together drive the changes of the menstrual cycle. Reproductive examinations call for privacy, consent and a chaperone where the practice requires it, covered in unit fourteen.

Four entries on the conditions you measure most: diabetes and its signs, high blood pressure, and cholesterol.

Too much glucose, two causes.

MAS 089 Diabetes and Its Main Types

Diabetes means blood glucose runs too high, because the body makes too little insulin or cannot use it well. In type one, the immune system destroys the insulin-making cells; it is usually found in the young, though it can appear at any age. Type two, the most common, is cells not using insulin well while the pancreas cannot keep up. Gestational diabetes develops in pregnancy and usually resolves after birth, though it raises the chance of type two later. Prediabetes is glucose above normal but below a diagnosis of type two. Explaining risk and treatment is the provider's role; yours is accurate testing and careful recording.

What patients mention.

MAS 090 Signs of Diabetes

Common signs of diabetes include more urination, strong thirst and hunger, blurred vision and tiredness. Sores that do not heal and frequent infections, such as urinary, skin or yeast infections, are also common signs. When a patient mentions these, record them in the patient's words and tell the provider.

No symptoms until harm.

MAS 091 High Blood Pressure Is Often Silent

High blood pressure usually causes no symptoms until it has already done serious harm. That is why blood pressure is measured at so many visits; a pattern of readings at or above one hundred thirty over eighty counts as high. A patient who feels fine can still have a dangerous reading, so report every high reading.

Hardening from injury.

MAS 092 Cholesterol and Hardened Arteries

Too much bad cholesterol in the blood, called hyperlipidemia, raises the risk of heart disease and stroke. Injury to an artery's lining, from high glucose, tobacco or excess blood fats, starts inflammation that leaves the wall scarred and stiff; this is atherosclerosis. Many risk factors cause artery damage together, so record smoking and diet history accurately.

Five entries on heart and lung disease, ending with a constructed morning of three rooming visits.

Coronary disease and heart attack.

MAS 093 Coronary Artery Disease and Heart Attack

Coronary artery disease happens when plaque narrows the arteries that feed the heart muscle. When a coronary artery becomes blocked, part of the heart loses its oxygen and muscle cells die; this is a myocardial infarction, commonly called a heart attack. Chest pain is always reported to the provider at once, never left for later.

When the pump falls short.

MAS 094 Heart Failure

Heart failure means the heart cannot pump enough blood to meet the body's needs. When the right side fails, too little blood reaches the lungs; when the left side fails, too little oxygen-rich blood reaches the rest of the body. Heart failure does not mean the heart has stopped; it is a long-term condition that the provider manages over many visits.

Inflamed, swollen, tightened.

MAS 095 Asthma

Asthma is a long-term disease in which the airways become inflamed, swollen and tightened. Inflammation, swelling and spasm of the airways block air from entering, and extra mucus adds to the blockage; it affects adults and children alike. An asthma attack can worsen quickly, so report wheezing or labored breathing at once.

A smoking-linked lung disease.

MAS 096 Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease, known as COPD, is a long-term inflammatory lung disease that blocks airflow out of the lungs. Its symptoms include difficult breathing, cough, mucus and wheezing; it most often follows long-term smoking. Chronic bronchitis is one of the conditions grouped under COPD.

Three rooms, three findings.

MAS 097 A Morning of Chronic Conditions

A constructed morning pays off the opening idea across three rooms. The first patient, with type two diabetes, mentions a foot sore that has not healed in weeks. Knowing slow-healing sores are a sign, she records it in his words and tells the provider before the provider enters. The second patient feels fine and wants a refill, but her blood pressure is high. Knowing it is often silent, the assistant rechecks as the procedure directs, records both readings and reports them. The third patient came about a rash, but pauses for breath with a faint wheeze. Asthma can worsen quickly, so the assistant stops the intake and tells the provider at once. In no room did she explain a finding or suggest a cause. Reassuring or warning a patient would have moved her from reporting into diagnosis.

Look at what you can now do. You can describe the heart's chambers and valves, the vessels, what pulse and blood pressure measure, and the heart's own pacemaker. You can outline how breathing works, how food moves through the digestive tract, how urine is made and stored, and what the reproductive organs release. You can name the types and signs of diabetes, and explain why high blood pressure is measured so often. And you can recognize heart and lung conditions that call for an immediate report. Unit Five turns to medications: how drugs act, how they are named, and how they are classified.