Medical Assistant Exam: Clinical Procedures - Preparing and Maintaining the Treatment Area

The medical assistant is largely responsible for preparing and maintaining the treatment area. This guide reviews the important aspects of this vital function.

Equipment and Materials
Instruments and equipment must be properly maintained, and all maintenance procedures must be documented. A maintenance log provides a complete record of all work performed on instruments or on a piece of equipment. The medical assistant must be sure to follow manufacturers’ guidelines for performing instrument and equipment maintenance.

Examination Tables
Examination tables usually come with storage drawers to provide plenty of storage volume for gowns, drapes, and other items, yet are made to help organize the medical office’s assortment of smaller supplies and bulk supplies. In addition, there are front drawers for easy access to items during pelvic exams.
The one-piece, upholstered top of the examination table can be easily removed without tools, to allow for thorough cleaning. The footstep allows patients to feel more secure and to get on and off the table more confidently. The medical assistant should always assist the patient on and off the examination table. Retractable stirrups pull out straight and are then positioned in four lateral positions.

Autoclave/Sterilizer
Information about the use and operation of an autoclave—used to sterilize equipment—is included in the Infection Control guide on Fatskills.

Cast Equipment/Materials
Casts are applied to immobilize a fracture and allow the bone to heal in proper alignment. The type of cast to be used depends on the location and severity of the injury, the age and occupation of the patient, and the physician’s preference. Different types of casts include:
- An air cast is a temporary cast that is inflated around the limb to immobilize it and can be used if some mobility is allowed. If no mobility is allowed, the patient will be fitted with a fiberglass cast, which is the most common type of cast.
- A plaster cast is a bandage impregnated with calcium sulfate crystals and is supplied as rolls of material in widths appropriate to a variety of sites. After water is added to the dry rolls of bandages and the wet bandages are applied to the area, a chemical reaction generates heat. This chemical reaction produces a rigid dressing when dry, in about 72 hours. The bandage molds to the area as it is applied. Plaster casts must be kept dry at all times.
- A fiberglass cast is applied in a manner similar to plaster casts; the polyurethane additives used in fiberglass casts harden in minutes, eliminating the extended drying time. The fabric has a more open weave than plaster, which helps maintain skin integrity.

The medical assistant must instruct the patient in proper cast care. The guidelines are as follows:
- Cover the cast when bathing.
- Keep the cast dry and exposed to air as much as possible.
- Elevate the cast to reduce swelling and pain.
- Observe the fingers and toes for changes in color, temperature, and decreased sensation.
- Call the office if there is any bad odor, loss of sensation, numbness, tingling, or bleeding around the cast.
- Clean the cast with a damp cloth.

Scales
Although many types of scales are available for measuring weight, the most common in the medical office is the balance beam scale, because of its accuracy. Some important points of operation are:

1. Weights that slide above two rows of numbered measurements indicate the weight.
- The bottom row shows measurements in 50-pound units.
- The top row shows measurements in 2-pound units.

2. The bottom row—which jumps in bigger increments—should first be moved to get the general range of the individual’s weight.

3. The top row is then adjusted to measure the weight exactly.

4. The beam will be in balance when all weights are at set to zero and when the pointer at the end of the balance bar floats in the middle of the frame.

Oxygen
Adequate amounts of oxygen are vital to the proper functioning of the body and the health of the body’s organs. If a patient’s breathing is labored, supplemental oxygen may needed. Important aspects of administering oxygen are:
- Explain the procedure to patient and review safety precautions necessary when oxygen is in use.
- No Smoking signs should be placed in the appropriate areas.
- A doctor’s prescription will dictate how much oxygen should be used.
- A mask should be used if the amount of oxygen to administer is between 5 and 15 liters per minute.
- A nasal cannula, that is, tubing connected to the larger oxygen delivery tubes, should be used if the amount to administer is 6 liters or less per minute.
- Humidification can be added to help keep the inside of the patient’s nose from drying. Sterile water must always be used.
- The nasal prongs—which are attached at the end of the cannula leading into the nostrils—should point downward.
- The patient should be encouraged to breathe through the nose while keeping the mouth closed.

Spirometer
Spirometry is a test to measure breathing capacity. An instrument called a spirometer measures the air taken in by and expelled from the lungs. Several different measurements related to lung volume and capacity can be made with a spirometer. Some of these measurements are made directly by the spirometer; others are calculated.
The following procedure should be followed when performing spirometry on a patient:
- The patient should be in a sitting position with legs uncrossed and both feet on the floor.
- The patient’s chin should be slightly elevated, and the patient’s neck should be slightly extended.
- A nose clip should be securely placed on the patient’s nose.
- The patient should take as deep a breath as possible, and the patient should blow in the mouthpiece as hard and as fast as possible.
- The patient should complete three acceptable sessions.
If the results are less than 60 percent of the predicted value, the patient may be given bronchodilators (medication used to dilate the bronchi, or air passages), and be retested to determine the impact of the inhalant on function after the bronchodilator has been administered.

Nebulizer
A nebulizer is a device used for patients who have symptoms of asthma, including wheezing and difficulty breathing. A bronchodilator (a medication administered to dilate the bronchi), such as albuterol, is added to the nebulizer, which causes the liquid medication to break apart into a fine spray that is inhaled by the patient through a mouthpiece or mask. Because bronchodilator medications can cause an increase in heart rate, the patient’s pulse should be monitored before, during, and after the treatment.

Oximeter
An oximeter is a device that measures oxygen levels in the blood, as well as an individual’s pulse rate. A probe is placed on a relatively translucent area of the body, such as a fingertip or earlobe; a portable fingertip unit can be placed directly on the fingertip. The oximeter then uses beams of red and infrared light to calculate the amount of oxygen the blood sample running by the probes, or unit, contains.

Thermometer
A thermometer is used to measure body temperature, which is one of the vital signs used to assess an individual’s health status. A person’s temperature can be measured at different sites in the body. Normal body temperature varies with the time of day and the site of measurement. Normal body temperature is between 96°F and 99.5°F (36.4°C to 37.3°C).
More information about body temperature can be found under 'Vital Signs' on page 168.

Sphygmomanometers
The aneroid sphygmomanometer is an instrument used to measure blood pressure. The instrument consists of:
- an inflatable cuff
- an inflation bulb with a control valve
- a pressure gauge, with the needle pointing to a scale showing millimeters of mercury

Blood pressure cuffs come in a variety of sizes: one for adults, one for children, and one to fit around the thigh. The size of a cuff refers to its inner inflatable bladder. The cuff should fit snugly and should be applied so that the center of the inflatable bag is directly over the brachial artery to allow for complete compression of the artery. The cuff has a velcro fastener to hold the cuff in place.
The aneroid sphygmomanometer should be recalibrated at least once a year.
A stethoscope, for listening to the heartbeat, is also needed to measure blood pressure. The measurement is recorded in millimeters of mercury (mm Hg). It is usually given as two numbers, for example, 110 over 70 (written as 110/70).
- The top number is the systolic blood pressure reading. It represents the maximum pressure exerted on the artery walls when the heart
contracts.
- The bottom number is the diastolic blood pressure reading. It represents the minimum pressure in the arteries when the heart is at rest.

Stethoscope
The acoustic stethoscope is a diagnostic device through which an examiner listens to sounds from within a patient. The parts of a stethoscope include:
- the diaphragm, which picks up high-pitched sounds and is often referred to as the chestpiece, because it is most frequently used on the chest to pick up sounds in the chest cavity.
- the bell, which is the cone-shaped side of the stethoscope chestpiece. It must be held lightly against the skin to amplify sound. The bell is best at amplifying low-pitched sounds, such as vascular and heart sounds.
- earpieces, which are connected to the chestpiece through tubing. When the earpieces are placed in the examiner’s ears, the acoustic waves coming from inside the patient can be heard.

Electrocardiograph
The electrocardiogram (ECG or EKG) is the written record of electrical current as it moves through the heart. The electrocardiograph machine is connected to the patient with wires and electrodes that are sensitive to the electrical impulses generated by the patient’s heart. This electrical activity is transmitted to the main unit of the electrocardiograph machine and is represented on electrocardiograph paper through specific waveforms, which are then reviewed and analyzed by the physician.
The waves of electrical impulses responsible for cardiac cycle produce a series of waves and lines on an electrocardiogram, which is the tracing made by an electrocardiograph. These peaks and valleys, called waves or deflections, are labeled with the letters P, Q, R, S, T, and U. Each letter represents a specific part of the pattern.
The information obtained aids in the diagnosis and treatment of cardiac problems (such as ischemia or arrhythmias); abnormalities in the size of the waves or the various time intervals indicate certain types of heart problems. ECGs are also commonly done prior to major surgical procedures in order to establish baseline health information about a patient and to identify potential cardiac disorders.

The Stylus and Paper
The horizontal axis of the paper represents time and the vertical axis represents amplitude. The stylus marks the ECG paper as it moves horizontally at a rate of 25 mm/sec.
The voltage, or strength, of the heartbeat is also recorded on the paper. Voltage can be displayed as either a positive or a negative deflection. One millivolt (mV) of electrical activity moves the stylus upward over 10 mm.
All ECG machines are standardized so that an ECG can be interpreted in the same manner, regardless what part of the world a patient is in. Standardization needs to be checked each time the ECG machine is used; the manufacturer’s manual explains exactly how the standardization process works.

Leads and Electrodes
Ten sensors called electrodes are placed on the patient’s arms, legs, and chest to pick up the electrical activity of the heart. Each of the electrodes is connected to color-coded lead wires by a metal clip. The lead wires transmit data about cardiac electrical activity to the ECG machine. Each lead records the electrical impulse through the heart from different angles. The ECG machine amplifies the electrical waveforms created by deflection of the stylus.
The standard ECG consists of 12 separate leads, or recordings, of the electrical activity of the heart from different angles. The 12-lead ECG produces a three-dimensional record of the impulse wave.
Lead I to lead III: The first three leads recorded are called the standard, or bipolar, leads because each of these leads uses two limb electrodes to record the heart’s electrical activity. The right arm electrode is the negative pole, and the left leg or left arm electrodes are the positive poles. Roman numerals I, II, and III are used to identify the leads. These leads are also known as Einthoven leads, and they show a frontal view of the heart’s activity from side to side.
Augmented leads: The augmented leads are designated voltage right arm (aVR), augmented voltage left arm (aVL), and augmented voltage left leg (aVF). The electrical activity recorded by these leads is small, so the ECG machine amplifies or augments the electrical potential when recorded. These are all unipolar leads with a single positive electrode that uses the right leg for grounding.
Precordial leads: The precordial, or chest, leads are unipolar and provide a transverse-plane view of the heart. They are identified as V1, V2, V3, V4, V5, and V6. The V means 'chest,' and each of the numbers represents a specific location on the chest. Precordial leads measure the electrical activity among six specific points on the chest wall and a point within the heart.

ECG Artifacts
Artifacts are caused by improper technique, poor conduction, outside interference, or improper handling of a tracing.
Because electrocardiograph machines are sensitive to electrical activity, they sometimes record electrical activity from sources other than the patient’s heart. Examples include electricity from nearby equipment or even the patient’s own noncardiac muscle movement. When the ECG stylus moves in response to this interfering electrical activity, it records markings on the ECG strip known as artifacts, which are distracting and irrelevant.

Microscopes
The microscope, an optical instrument consisting of one or more lenses used to magnify objects, is used in the medical office to examine microorganisms and to count cells. The compound microscope is the most common type used in the medical office.
Binocular microscopes minimize eyestrain and have adjustments to allow for variations in spacing between the user’s eyes.

Parts of a Microscope
- The eyepiece has three or four objective lenses and rotates to bring the objective into working position. The grip should be used to rotate the lenses.
- The objective lenses determine the magnification power of the microscope. The magnification power is marked on each objective. The longer, or higher power, objective magnifies × 40 (for closer observation). With the use of oil, the third objective, sometimes called the oil immersion lens, magnifies × 100.
- The stage of the microscope is a flat surface that holds the slide for viewing. An opening in the solid surface allows illumination of the slide from below.
- The condenser concentrates the focus of the light rays on the slide. The condenser is adjustable. In the lower position, the light focus is reduced; in the higher position, it is increased.
- The diaphragm, located in the condenser, consists of interlocking plates that adjust into variable-sized openings, or irises, thus controlling the amount of light from the source in conjunction with the condenser. The greater the need for light, the more highly magnified the slide must be.
- The light source is housed in the base of the microscope.

Several precautions should be used when handling the microscope.
- The microscope should be lifted with one hand holding the arm and the other hand under the base.
- The microscope should be operated on a sturdy surface.
- The lenses of the eyepieces or of any of the objectives should not be touched.
- Lenses should be cleaned with lens paper dipped in lens cleaner.
- The stage and other metal parts should be kept free of excess oil.

Ophthalmoscope
The ophthalmoscope is a lighted instrument used to examine the interior of the eye. It consists of:
- the base, or handle
- the concave mirror
- a light source
- rotating disks of lenses, operating by dials, which allows a patient’s eyes to be viewed at various depths and magnifications

The examiner can view specific landmarks on the patient’s fundus, such as the optic nerve, which transmits visual information from the eye to the brain, and the macula, an oval-shaped part of the eye that absorbs excess blue and ultraviolet light.

Otoscope
An otoscope is a device used to look into the ear. The head of the otoscope houses a light source and a lens that magnifies at a low power. An ear speculum, used to open up the ear canal, is placed at the front end.
To examine the ears of an adult, the ear canal must be straightened by pulling on the pinna (the projecting part of the ear lying outside of the head), and then the ear speculum is inserted in the external ear canal. When examining children’s ears, the examiner should pull the top of the child’s ear up and out to straighten the ear canal.

Endoscopes
An endoscope is an instrument used to see inside a hollow part of the body. It is made up of a flexible or rigid tube (or shaft), an eyepiece with a light source, an opening for inserting instruments, and a system of lenses that transmits images of what is being viewed.
There are a variety of types of endoscopes, depending on which part of the body is being examined, including:
- gastrointestinal tract: gastroscope, colonoscope, sigmoidoscope
- air passageways: bronchoscope, nasopharyngoscope
- urological system: cystoscope, ureteroscope

The medical assistant may be called upon to assist in endoscopic examinations. His or her primary role is to assist the patient into the correct position and to drape the patient properly.

Mobility Assistive Devices
Patients who require assistance to maintain mobility may use crutches, a cane, a walker, or a wheelchair. Medical assistants often are responsible for teaching patients how to use these ambulatory aids safely.

Crutches
One crutch or a pair of crutches can be used to assist an individual with his or her gait, or way of walking. Crutches can be made of aluminum or wood. Axillary crutches are fitted to the patient’s armpit height. The axillary bars, the padded parts at the top of the crutches, should fit two inches below the patient’s axillae, or armpits.

Canes
A cane is used when a patient needs extra support and stability, but requires only a small measure of assistance. The tripod (three legs) or quad (four legs) cane is useful when the patient needs stability. The tripod cane stands alone when the patient needs to use his or her hands or have other support. To measure for proper cane length, have the patient stand erect. The cane should be level with the patient’s hips and the patient’s elbow should be bent at a 30° angle.

Walkers
A walker is a lightweight aluminum frame on which a patient can lean for stability while walking. The walker frame should be level with the patient’s hip, and the patient’s elbow should be bent at about a 30° angle.

Wheelchair
A wheelchair is a mobility device to assist people who have difficulty walking or are unable to walk because of illness, injury, or disability. The wheelchair dimensions—such as seat height, width, and depth—are important in allowing for a proper fit. It depends not only on an individual’s size, but also on his or her needs. For instance, the height of the seat is important if individual needs to use the wheelchair at an office desk.