Skills / Vital Signs Monitoring / Introduction to Vital Signs Monitoring / Vital Signs Monitoring: BP, Pulse, Temp, and SpO2 for New CNAs
Vital Signs Monitoring

Vital Signs Monitoring: BP, Pulse, Temp, and SpO2 for New CNAs

45 min read Training Guide

Blood pressure, pulse, temperature, and SpO2 - the vitals CNAs and medical assistants take on every patient, with normal ranges and the red flags to report.

Table of contents

What the work looks like

Vital signs are the basic measurements taken on every patient at every visit or shift check: blood pressure, heart rate (pulse), body temperature, and oxygen saturation (SpO2). Respirations round out the "big five" on any clinically detailed check. They are the first objective data the care team uses to judge whether a patient is stable, deteriorating, or improving. Getting them right, and recognizing when a reading is outside expected range, is what turns a CNA or medical assistant from a task-taker into a clinical observer the nurse can rely on.

A new CNA on a med-surg floor takes vitals on every assigned patient at the start of shift, at scheduled intervals (every 4 or 8 hours for stable patients, every 15 to 30 minutes for post-op or unstable patients), and any time the patient's condition changes. A medical assistant in an outpatient clinic takes them at check-in on every visit and enters them into the EMR (Epic, Cerner, Athenahealth, Allscripts) before the provider walks in.

Job titles: CNA, Home Health Aide (HHA), Medical Assistant (MA), Patient Care Technician (PCT), Medication Aide. Pay $15 to $24 per hour; hospital settings typically pay higher than long-term care. CNA requires state registry; MA does not in most states but employers prefer CAAHEP- or ABHES-accredited program graduates.

Safety and tools

Normal adult ranges to memorize:

  • Blood pressure: systolic 90 to 120, diastolic 60 to 80. Stage 1 hypertension starts at 130/80. A systolic over 180 or diastolic over 120 is hypertensive crisis; call the nurse immediately.
  • Pulse: 60 to 100 beats per minute at rest. Under 60 (bradycardia) or over 100 (tachycardia) is a call unless the patient's baseline is known to be outside.
  • Temperature: 97.8 to 99.1 F oral. Fever at 100.4 F and above. Site matters: rectal reads about 1 F higher than oral, axillary about 1 F lower, temporal artery is site-variable.
  • SpO2 (pulse oximetry): 95 to 100 percent on room air. Under 92 is a call on most adult patients; COPD baselines run lower and should be noted in the care plan.
  • Respirations (often counted alongside): 12 to 20 per minute at rest. Count discreetly; patients alter breathing when they know you are counting.

Tools: manual sphygmomanometer with stethoscope (the gold standard; every CNA program trains on it), automated BP monitor (Welch Allyn, Omron), digital thermometer (oral and rectal probe covers), temporal artery scanner (Exergen), pulse oximeter (fingertip clip), watch with a second hand for manual pulse and respiration counts, gloves, alcohol prep pads.

Safety and technique:

  • Hand hygiene before and after every patient. Wipe shared equipment (BP cuff, thermometer, pulse ox) with a hospital-grade disinfectant wipe between patients (infection control).
  • BP cuff sizing matters: a cuff too small reads high, too large reads low. The cuff bladder should cover 80 percent of the upper arm circumference.
  • HIPAA: vital signs are PHI. Do not discuss them in a public hallway or on social media.
  • Reporting: if a reading is outside expected range or the patient looks unwell even with normal numbers, tell the nurse. Your job is observation plus escalation, not diagnosis.

Your first exercise

Practice on yourself or a willing family member (with permission). Take a manual blood pressure with a cuff and stethoscope: palpate the brachial pulse in the antecubital space, place the bell over it, inflate to 30 mmHg above the point the pulse disappears, release at 2 mmHg per second, note the first Korotkoff sound (systolic) and the point sounds disappear (diastolic). Take your own pulse for a full 60 seconds on the radial artery. Place a fingertip pulse oximeter and note SpO2 and heart rate. Take temperature with whatever digital thermometer you have. Record all four in a notebook with the time.

Doing this five times across a week builds the technique and the comfort that every clinical shift will demand.

Where to go next

Build on Vital Signs Monitoring with Infection Control, Patient Care & Comfort, Introduction to Medical Terminology, Diabetes Management (Introduction to Diabetes Management), HIPAA & Patient Privacy, and Wound Care (Introduction to Wound Care). Safety: Bloodborne Pathogens, Hand Hygiene, Workplace Safety. Promotion path: CNA -> PCT -> LPN -> RN, or MA -> Lead MA -> Clinic Manager.