8.1 Understanding Vital Signs and Normal Ranges

Why Vital Signs Matter on the INACE

Vital signs are objective measurements of the body's most basic life-sustaining functions. They are called "vital" because they reveal, in numbers, whether the heart, lungs, and temperature-regulating systems are working within safe limits. On the Illinois Nurse Assistant Competency Examination (INACE) — administered by Southern Illinois University Carbondale (SIU) — the Basic Nursing Skills content area makes up roughly 20% of the 85-question written test, and several of the 21 mandated performance skills require you to measure and record vital signs accurately.

To pass, you must clear the written test (a scaled cut score; prep guidance commonly targets roughly 75% or higher) and pass the skills evaluation, which is scored as critical-element pass/fail rather than a percentage. On the skills station, an inaccurate or unsafe vital-sign measurement is a common failure point, so memorize the normal ranges and reportable thresholds cold.

The Five Vital Signs

When to Take Vital Signs

Vital signs are not taken at random. A certified nursing assistant (CNA) measures them at these key times:

• On admission — to establish a baseline for comparison
• At scheduled times — per the care plan (e.g., every shift, twice daily)
• Before and after a procedure — to detect adverse effects (e.g., after a tub bath)
• When the resident's condition changes — to catch deterioration early
• When the resident complains of dizziness, chest pain, or feeling unwell
• Before the nurse gives a PRN (as-needed) medication — the nurse needs your numbers first
• As ordered by the physician for specific monitoring

Factors That Change Vital Signs

A reading that looks abnormal may have a simple, expected cause. Knowing these factors prevents false alarms and helps you decide what to report.

Worked Example

A resident returns from physical therapy and you take a pulse of 104 bpm. Before alerting the nurse, you recall that activity raises pulse. You let the resident rest 10 minutes, recount, and get 84 bpm — within normal limits. You document both readings. This shows the examiner you understand context, not just numbers.

What to Report Immediately

Memorize this table — these thresholds appear repeatedly on the written test.

Common Traps

• Trap: Thinking a CNA "diagnoses" or treats abnormal vitals. You observe, record, and report — the nurse interprets and acts.
• Trap: Rounding or estimating. Record the exact number you obtained.
• Trap: Forgetting to document who you notified. Always note the nurse's name and response.

Documentation Standard

Every vital sign entry must include the date and time, the method/site (e.g., "oral," "right arm"), the position (sitting, lying, standing — critical for BP), any abnormal finding and to whom it was reported, and your name and title (CNA). Never document a vital sign you did not personally take, and never "pre-chart" before measuring.

Order of Taking Vital Signs

Many programs teach a logical sequence so the resident stays calm and readings are not artificially raised. A common order is temperature, then pulse, then respirations, then blood pressure, and finally pain. Pulse and respirations are taken together, with respirations counted while you appear to still hold the wrist. Blood pressure is often saved for last because cuff inflation can briefly make an anxious resident's pulse and breathing rise. Always seat the resident, let them rest, and explain each step before you begin.

Baseline Versus Trend

A single reading rarely tells the whole story. The baseline taken on admission is the yardstick; what matters most is the trend — whether numbers are climbing or falling over hours and days. A blood pressure of 138/86 may be normal for one resident and alarming for another whose baseline is 110/70. This is why complete, legible documentation is part of resident safety, not just paperwork: the nurse compares your number to the resident's own history to decide whether it signals a problem.