Yes, certified nursing assistants (CNAs) take vital signs as one of their core daily responsibilities. Measuring vitals is a fundamental skill taught in every CNA training program, tested during certification exams, and performed routinely in hospitals, nursing homes, and other care settings. In many facilities, CNAs are the staff members who take vitals most frequently.
Which Vitals CNAs Measure
CNA training covers seven key measurements that fall under the vital signs umbrella:
- Body temperature
- Pulse (heart rate)
- Respiratory rate
- Blood pressure
- Oxygen saturation, measured with a finger clip (pulse oximeter)
- Pain level, typically using a 0-to-10 scale
- Blood glucose, using a fingerstick monitor
The first four are the “classic” vital signs you’ll encounter in virtually every CNA role. Oxygen saturation, pain assessment, and blood glucose monitoring are increasingly standard parts of the job, though the exact tasks a CNA performs can vary by facility and state.
What CNAs Can and Can’t Do With the Results
CNAs collect vital sign data, but they don’t make clinical decisions based on it. That distinction is central to how nursing care is legally structured. A CNA measures a blood pressure reading; a registered nurse (RN) or licensed practical nurse (LPN) interprets what that reading means for the patient’s treatment plan. The delegated task cannot require the CNA to exercise professional nursing judgment.
That said, CNAs are trained to recognize when numbers fall outside normal ranges and must immediately report those readings to the supervising nurse. The general thresholds drilled into CNA training include:
- Temperature: above 100.4°F (38°C), which indicates a fever
- Pulse: below 60 or above 100 beats per minute in adults
- Respiratory rate: below 12 or above 20 breaths per minute
- Blood pressure: any reading outside the patient’s normal range
If a patient shows signs of respiratory distress while a CNA is taking vitals, the expectation is to stop and notify the nurse immediately rather than finish the routine. Any significant change in a patient’s breathing, circulation, cognition, or pain level also triggers an immediate report.
How Delegation Works
Vital sign measurement is a nursing task that gets delegated down to CNAs by the supervising RN. This delegation follows a structured process. In Texas, for example, state regulations require the RN to assess the patient’s needs, confirm the CNA is competent in the task, provide adequate supervision, and periodically re-evaluate whether delegation remains appropriate, especially when a patient’s condition changes.
Most states follow a similar framework built around what’s known as the “five rights of delegation”: the right task, the right person, the right circumstances, the right communication, and the right supervision. The practical takeaway is that a CNA doesn’t just independently decide to start taking vitals. An RN must determine it’s safe and appropriate for that particular patient, and the CNA must have demonstrated competence in the skill.
How the Setting Affects the Role
CNAs take vitals in both hospitals and long-term care facilities, but the pace and frequency differ significantly. In hospitals, patients tend to be more acutely ill, which means vitals are checked more often, sometimes every few hours or even more frequently for unstable patients. Hospital CNAs get extensive practice with vital sign measurement simply because it’s needed so often.
In nursing homes and assisted living facilities, the schedule is typically less intense. Vitals might be taken once or twice per shift for most residents, or on a set schedule like weekly for stable, long-term residents. The measurements still matter, but the urgency is usually lower. Regardless of setting, the core skills are the same: CNAs in both environments are trained in obtaining vitals, bathing and dressing patients, and providing personal care.
Vital Signs on the CNA Certification Exam
If you’re considering becoming a CNA, expect vital signs to be a major part of both your coursework and your state certification exam. Knowing how to accurately measure vital signs and understanding their normal ranges is a requirement for earning certification. Most state exams include a written portion covering vital sign knowledge and a hands-on skills test where you demonstrate the actual measurement techniques, often including blood pressure and pulse measurement using manual equipment.
Training programs typically spend significant time on proper technique: positioning the blood pressure cuff correctly, counting respirations without the patient noticing (which can alter their breathing pattern), finding the right pulse point, and reading a thermometer accurately. These aren’t just test skills. They’re the tasks you’ll perform dozens of times per shift in your first job.