4.4 Monitoring During Exercise (PTA Critical)
Key Takeaways
- Stop exercise immediately if Systolic Blood Pressure (SBP) drops 10 mmHg or more during an increasing workload - this signals a failing left ventricle response.
- Stop and notify the supervising Physical Therapist (PT) if SBP rises to 250 mmHg or higher, or Diastolic Blood Pressure (DBP) rises to 115 mmHg or higher.
- A Heart Rate (HR) that falls as workload increases is abnormal and is a stop sign - normally HR rises in proportion to intensity.
- New chest pain, unexpected dyspnea, mental status changes, pallor, diaphoresis, or claudication require the PTA to stop, monitor, and report.
- Oxygen saturation (SpO2) thresholds for stopping vary by Plan of Care (POC); a commonly cited PTA threshold is SpO2 less than 88-90%.
Why PTAs Get Tested on This So Hard
The NPTE-PTA writes scenarios that hand you a single vital sign change and expect you to choose 'stop and report' versus 'modify and continue' versus 'progress'. Knowing the stop list cold is the single highest-yield study task in this domain.
Normal vs Abnormal Responses
| Parameter | Normal Exercise Response | Stop-Exercise Trigger |
|---|---|---|
| Heart Rate (HR) | Rises with workload | Drops with increased workload; rises more than about 20-30 bpm above resting in patients with strict prescribed limits (e.g., post-MI Phase I) |
| Systolic Blood Pressure (SBP) | Rises 8-12 mmHg per Metabolic Equivalent of Task (MET) | Drops 10 mmHg or more during increasing workload; rises to 250 mmHg or higher |
| Diastolic Blood Pressure (DBP) | Stays the same or changes less than 10 mmHg | Rises to 115 mmHg or higher; rises more than 10 mmHg above resting |
| Respiratory Rate / Dyspnea | Increases proportionately | Dyspnea disproportionate to effort, audible wheeze, accessory muscle use at low load |
| Oxygen Saturation (SpO2) | Stays close to baseline | Falls below the Plan of Care (POC) parameter; common PTA cutoff is below 88-90% |
| Rating of Perceived Exertion (RPE) | Climbs gradually toward target | Jumps to 15+ on the 6-20 Borg scale, especially with chest pain or dyspnea |
| Mental Status | Alert and oriented | Confusion, sudden agitation, lightheadedness, syncope |
| Skin | Mild flushing or sweat | Pallor, cyanosis, cold and clammy diaphoresis |
The PTA Stop-and-Report List
If any of the following appears, stop exercise, position the patient safely (usually seated or supine with feet up), monitor vitals, and notify the supervising PT and medical team:
- New or worsening chest pain, jaw pain, or arm pain suggesting angina.
- Dyspnea disproportionate to effort or new audible wheeze.
- Lightheadedness, syncope, near-syncope, or new confusion.
- Pallor, cyanosis, or cold clammy diaphoresis.
- Claudication (leg cramping that resolves with rest) at a workload below the prescribed limit.
- SBP drops 10 mmHg or more during a rising workload.
- SBP at or above 250 mmHg or DBP at or above 115 mmHg.
- HR falls as workload increases.
- SpO2 drops below the POC parameter (commonly less than 88-90% on continuous monitoring).
- New abnormal cardiac rhythm, new murmur, or unexplained palpitations.
A Quick Decision Frame
When a scenario looks borderline, the PTA can run this checklist:
- Is there a stop-exercise sign on the list above? If yes, stop and report. Do not modify and continue.
- Is the change explained by something fixable (room is hot, patient skipped breakfast, fan off)? Try a short rest with vitals recheck once, then progress only if all values return to baseline.
- Is the change outside the PTA's scope (medication adjustment, new diagnosis, IV change)? Notify the PT and medical team and document.
Documentation
When something stops a session, document objective values (HR, BP, SpO2, RPE, exact symptom), the action taken, who was notified, and how the patient responded. Stop-exercise events are common citation points in NPTE-PTA professional-responsibility items.
During treadmill walking, a patient's HR drops from 110 to 85 with no rest while the speed is being increased. The PTA should:
A patient in Phase II cardiac rehabilitation has a resting BP of 132/82 mmHg. After 6 minutes on the bike, BP is 118/80 mmHg and the patient reports 'a little dizzy.' The PTA should first: