Clinical Competency
Clinical tasks are the largest part of the CMA (AAMA) exam and the core of what a medical assistant does at the point of care. This domain covers anatomy and physiology applied to patient care, infection control and asepsis, vital signs, phlebotomy and specimen handling, injections and medication administration, ECG, and assisting with exams and minor procedures. Master the exact numbers, the order of steps, and the reasons behind each rule, because the exam rewards knowing why as much as what.
Vital signs: the normal adult reference ranges
Commit the adult resting norms to memory. Oral temperature averages about 98.6 F (37 C), with a normal range roughly 97.0 to 99.0 F; rectal runs about 1 degree higher and axillary about 1 degree lower than oral. Adult pulse is 60 to 100 beats per minute; below 60 is bradycardia and above 100 is tachycardia. Respirations are 12 to 20 breaths per minute. Normal blood pressure is less than 120/80 mmHg; 120-129 systolic with diastolic under 80 is elevated, 130-139/80-89 is stage 1 hypertension, and 140/90 or higher is stage 2 (current ACC/AHA categories). Always select a cuff whose bladder encircles about 80 percent of the arm — a cuff that is too small gives a falsely high reading and one too large gives a falsely low reading. Pulse oximetry of 95-100 percent is normal. Radial pulse is the routine site in adults; the apical pulse (at the fifth intercostal space, left midclavicular line) is used for infants and when the radial pulse is irregular or hard to palpate.
Asepsis, infection control, and the order of the venipuncture draw
Medical asepsis reduces the number of microorganisms (handwashing, clean gloves, disinfecting surfaces); surgical asepsis removes all microorganisms and spores (sterile field, sterile gloves, autoclaved instruments). Hand hygiene is the single most effective way to prevent the spread of infection. For phlebotomy, follow the CLSI order of draw to prevent additive carryover: blood cultures first, then light-blue (sodium citrate, coagulation), then red or gold serum tubes, then green (heparin), then lavender (EDTA), and finally gray (sodium fluoride/oxalate). A classic memory phrase is 'Boys Love Ravishing Girls Like Girls' or 'Stop Light Red Stay, Green Light Go.' Filling the light-blue coagulation tube completely matters because the fixed 9:1 blood-to-citrate ratio is thrown off by a short draw, invalidating PT/INR results.
Injections: routes, sites, angles, and needle selection
Match the route to the correct angle and site. Intradermal (ID) injections, such as the TB skin test, go into the dermis of the inner forearm at a 10-15 degree angle with a 26-27 gauge, 3/8 to 1/2 inch needle, raising a wheal. Subcutaneous (SubQ) injections, such as insulin and heparin, go into fatty tissue at a 45 degree angle (or 90 degrees with a short needle) using a 25-27 gauge, 5/8 inch needle in the upper outer arm, abdomen, or thigh. Intramuscular (IM) injections go into muscle at a 90 degree angle with a 22-25 gauge, 1 to 1.5 inch needle; the deltoid holds up to about 1 mL, while the ventrogluteal site is preferred for larger or irritating volumes and is the safest gluteal site because it avoids the sciatic nerve. The vastus lateralis is the recommended IM site for infants. Always verify the six rights before giving any medication: right patient, right drug, right dose, right route, right time, and right documentation.