Recognizing Abnormal Vital Signs
Compare readings with a person's baseline, take orthostatic vitals when ordered and decide when to call the nurse or 911.
Table of contents
A vital sign is only useful if someone acts on it. Anyone can write down a number. The skill is knowing what is unusual for this person, checking that the number is real and getting it to the right person at the right speed. This guide is about that judgment. You still do not diagnose, but you decide quickly whether a reading can wait.
What You Will Be Able to Do
- Use a person's baseline and trend, not just a normal range.
- Check whether an abnormal number is real.
- Take orthostatic vital signs when ordered.
- Spot combinations of readings that point to danger.
- Decide who to call, and how fast.
Reference Ranges for Adults at Rest
| Vital sign | Usual range | Word for out of range |
|---|---|---|
| Blood pressure | Under 120 and under 80 | Hypertension (high), hypotension (low) |
| Pulse | 60 to 100 | Bradycardia (slow), tachycardia (fast) |
| Respirations | 12 to 20 | Bradypnea (slow), tachypnea (fast) |
| Oral temperature | 97.8 to 99.1°F | Fever (100.4°F or higher), hypothermia (under 95°F) |
| SpO2 | 95 to 100 percent | Hypoxemia (low oxygen) |
These are starting points. The care plan may set its own limits for this person, and those limits take priority.
Baselines and Trends
A person's baseline is what is normal for them. One reading rarely tells the whole story.
Mr. Green's systolic pressure usually runs about 150. Today it is 118, which looks perfect on a chart. For him, it is a 30-point drop. He also says he feels dizzy. That is worth a call.
Mrs. Adams has COPD. Her SpO2 runs 89 to 91 percent, and that is within her care plan. Today's 90 percent is not a change.
Look across the last few readings. A pulse that climbs 72, 84, 96 and 108 over a shift tells a story, even though only the last number is out of range. Mention the trend in your report.
Check the Number First
When a reading is abnormal, confirm it before you sound the alarm, unless the person looks seriously ill.
- Look at the person. Are they pale, sweaty, confused or short of breath?
- Check the equipment. Is it the right cuff, is the finger warm, is the sensor on properly?
- Check the conditions. Did they just walk, eat, drink something hot, smoke or get upset?
- Repeat the reading with careful technique, using manual methods if you can.
- If the second reading is also abnormal, report both.
Warning: If the person looks unwell, skip the recheck and get help now. Numbers can be normal in someone who is in danger, and a person who looks seriously ill always takes priority over a chart.
Taking Orthostatic Vital Signs
Orthostatic vital signs check how blood pressure and pulse respond to a change in position. They are used when someone is dizzy or falling, has been on bed rest or is taking medicines that lower blood pressure. A drop in pressure when standing is called orthostatic hypotension, and it is a leading cause of falls. Take these only when ordered, and stay close, because the person may faint.
- Have the person lie flat for at least 5 minutes, then take blood pressure and pulse.
- Help them sit or stand, according to the order, with a gait belt on and a chair behind them.
- Take the blood pressure and pulse again after 1 minute, and at 3 minutes if ordered.
- Ask about dizziness each time.
- Stop and help them sit or lie down if they feel faint.
- Record every number with its position, and any symptoms.
Orthostatic hypotension is generally defined as a drop of at least 20 mmHg in systolic pressure or 10 mmHg in diastolic pressure within 3 minutes of standing.
For example, lying 138/80, pulse 78. Standing at 3 minutes 112/68, pulse 98, says "a little dizzy." That is a 26-point systolic drop and a 12-point diastolic drop. Report it to the nurse.
Combinations That Mean Trouble
Reading each number alone can miss the pattern. You are not diagnosing, but these combinations call for a fast report.
| Pattern | Why it matters |
|---|---|
| Fast pulse with low blood pressure | The body may be struggling to keep blood flowing |
| Fever with a fast pulse, fast breathing or new confusion | May be a serious infection such as sepsis |
| Low SpO2 with fast breathing | The body may not be getting enough oxygen |
| High blood pressure with a severe headache, weakness or trouble speaking | Possible stroke or other emergency |
| Slow, shallow breathing with sleepiness in someone on opioids | Possible overdose |
Sepsis is the body's life-threatening response to an infection. Early signs can include fever or low temperature, chills, confusion, shortness of breath, a fast heart rate, severe pain and clammy skin. Older adults may show only confusion or weakness.
Who to Call and How Fast
| Finding | Action |
|---|---|
| Unresponsive, not breathing normally, severe trouble breathing, chest pain, signs of stroke | Call 911 first |
| Over 180 or over 120 with symptoms | Call 911 |
| Over 180 or over 120 with no symptoms | Recheck in a minute, then tell the nurse right away |
| Systolic under 90 or well below baseline | Tell the nurse right away |
| Fever of 100.4°F or higher | Tell the nurse right away |
| SpO2 under 92 percent or below the care plan limit | Tell the nurse right away |
| Pulse under 60 or over 100, respirations under 12 or over 20 | Recheck and tell the nurse |
| Slightly out of range, with no symptoms and no change from baseline | Record it and mention it in your report |
Reporting and Recording
Give the nurse the numbers, the baseline and what you see:
"Mr. Green's blood pressure is 118 over 70 on two readings. He usually runs about 150 systolic. His pulse is 102 and he says he feels dizzy when he stands. Could you come see him?"
Record each reading with the time, site, position and any symptoms, along with who you told and when. If the record has a numeric field, enter the exact measured values in the standard format, such as 120/80. Never adjust a number to look more normal.
Common Mistakes
| Mistake | What it costs |
|---|---|
| Comparing only to the textbook range | Dangerous changes look normal |
| Rechecking again and again instead of reporting | Delays care |
| Ignoring how the person looks | A very sick person gets missed |
| Standing someone up without a chair or belt during orthostatic checks | A fall |
| Reporting a number with no baseline or trend | The nurse has no context |
Check Your Understanding
1. A patient who usually runs 110/70 reads 110/70 today, but she looks pale, sweaty and confused. Does her normal number matter?
No. Her appearance matters more. Get help right away.
2. A resident's SpO2 reads 84 percent, but he is chatting comfortably. What should you check first?
Check the equipment and the finger, warm his hand and repeat the reading. If it is still low, tell the nurse right away.
3. Lying down, a man's blood pressure is 130/78. After 3 minutes standing, it is 106/72. Is that a significant drop?
Yes. The systolic pressure dropped by 24 points, which meets the 20-point definition. Report it and keep him safe from falling.
4. A woman has a temperature of 101.2°F, a pulse of 112 and new confusion. What do you do?
Tell the nurse right away, or call 911 if she looks seriously ill. This combination can mean a serious infection.
Key Takeaways
- Compare each reading with the person's baseline and recent trend.
- Confirm abnormal readings, unless the person looks seriously ill.
- How the person looks outranks the number.
- Orthostatic hypotension means a drop of at least 20 systolic or 10 diastolic within 3 minutes of standing.
- Some combinations of readings need a faster response than any one number.
- Report the numbers, the baseline and what you see, and never change a value.