Key Takeaways
- Assess apical pulse for 1 full minute before giving heart rate-affecting medications
- Orthostatic hypotension is a drop of ≥20 mmHg systolic or ≥10 mmHg diastolic when standing
- Kussmaul respirations (deep and rapid) indicate metabolic acidosis
- SpO2 < 90% is critical and requires immediate intervention
- Report any significant deviation from baseline vital signs immediately
Last updated: January 2026
Vital Signs Assessment
Vital signs are the foundation of patient assessment, providing critical data about cardiovascular, respiratory, and neurological function. LPN/VNs must accurately measure, interpret, and report vital sign findings. This content area represents 9-15% of the NCLEX-PN exam.
Normal Vital Sign Ranges
| Vital Sign | Normal Adult Range | Concerning Values |
|---|---|---|
| Temperature | 97.8-99.1°F (36.5-37.3°C) | < 95°F or > 100.4°F |
| Pulse | 60-100 bpm | < 50 or > 120 bpm |
| Respirations | 12-20 breaths/min | < 10 or > 24 breaths/min |
| Blood Pressure | < 120/80 mmHg | > 140/90 or < 90/60 mmHg |
| Oxygen Saturation | 95-100% | < 90% (critical) |
Temperature Measurement
Temperature Routes:
| Route | Normal Range | Duration | Considerations |
|---|---|---|---|
| Oral | 97.6-99.6°F | 3-5 min (glass), 10-60 sec (digital) | Wait 15-30 min after eating/drinking |
| Tympanic | 98.6°F ± 1°F | 2-3 seconds | Pull pinna up and back (adults) |
| Temporal Artery | 97.4-100.1°F | 2-3 seconds | Sweep across forehead |
| Axillary | 96.6-98.6°F | 3-5 min | Less accurate, good for screening |
| Rectal | 98.6-100.6°F | 2-3 min | Most accurate; contraindicated in some patients |
Temperature Abnormalities:
- Hypothermia: < 95°F (35°C) - Medical emergency
- Fever: > 100.4°F (38°C)
- Hyperthermia/Hyperpyrexia: > 105.8°F (41°C) - Medical emergency
Pulse Assessment
Pulse Sites:
| Site | Location | Uses |
|---|---|---|
| Radial | Lateral wrist | Routine assessment |
| Apical | 5th intercostal space, MCL | Before digoxin, with irregular rhythm |
| Carotid | Lateral to trachea | CPR, assessing circulation |
| Brachial | Antecubital fossa | Blood pressure, infant CPR |
| Femoral | Groin | Emergency, circulation check |
| Dorsalis Pedis | Top of foot | Peripheral circulation |
| Posterior Tibial | Behind medial malleolus | Peripheral circulation |
| Popliteal | Behind knee | Lower extremity circulation |
Pulse Characteristics:
- Rate: Beats per minute
- Rhythm: Regular or irregular
- Quality/Strength: Bounding (3+), normal (2+), weak/thready (1+), absent (0)
- Equality: Compare bilaterally
Pulse Abnormalities:
- Tachycardia: > 100 bpm
- Bradycardia: < 60 bpm
- Pulse Deficit: Difference between apical and radial rates (indicates cardiac dysfunction)
Blood Pressure
Proper Technique:
- Patient seated quietly for 5 minutes
- Arm supported at heart level
- Correct cuff size (bladder covers 80% of arm circumference)
- Palpate brachial artery, place stethoscope diaphragm
- Inflate 30 mmHg above palpated systolic
- Deflate 2-3 mmHg per second
- First Korotkoff sound = systolic; last = diastolic
Blood Pressure Categories (AHA/ACC Guidelines):
| Category | Systolic | Diastolic | |
|---|---|---|---|
| Normal | < 120 | and | < 80 |
| Elevated | 120-129 | and | < 80 |
| Stage 1 HTN | 130-139 | or | 80-89 |
| Stage 2 HTN | ≥ 140 | or | ≥ 90 |
| Hypertensive Crisis | > 180 | and/or | > 120 |
Orthostatic (Postural) Hypotension:
- Drop of ≥ 20 mmHg systolic or ≥ 10 mmHg diastolic upon standing
- Measure lying, sitting, and standing (wait 1-3 minutes between positions)
- Common in elderly, dehydration, and with certain medications
Respiratory Assessment
Respiratory Characteristics:
- Rate: Breaths per minute (count for 30-60 seconds)
- Depth: Shallow, normal, or deep
- Rhythm: Regular or irregular
- Quality: Labored or unlabored
Respiratory Patterns:
| Pattern | Description | Associated Conditions |
|---|---|---|
| Eupnea | Normal breathing | Healthy individuals |
| Tachypnea | Rapid, > 20/min | Fever, anxiety, pain, hypoxia |
| Bradypnea | Slow, < 12/min | Opioids, increased ICP, sleep |
| Apnea | Absence of breathing | Life-threatening |
| Cheyne-Stokes | Crescendo-decrescendo with apnea | End of life, CHF, brain injury |
| Kussmaul | Deep, rapid | Metabolic acidosis (DKA) |
| Biot's | Irregular with apneic periods | Increased ICP, meningitis |
Oxygen Saturation (SpO2)
Pulse Oximetry Considerations:
- Normal: 95-100% (may be lower in COPD patients)
- Apply sensor to finger, toe, earlobe, or forehead
- Factors affecting accuracy:
- Motion artifact
- Poor perfusion (cold, hypotension)
- Nail polish (especially dark colors)
- Carbon monoxide poisoning (falsely high)
- Anemia (may be normal despite hypoxia)
When to Report Vital Signs
Immediate Reporting Required:
- Temperature > 101°F or < 96°F
- Pulse < 50 or > 120 bpm
- Respirations < 10 or > 24/min
- Blood pressure > 180/120 or < 90/60 mmHg
- Oxygen saturation < 90%
- Any significant change from baseline
- New onset of irregular rhythm
Test Your Knowledge
Before administering a medication that slows the heart rate, the LPN/VN should assess which pulse?
A
B
C
D
Test Your Knowledge
A patient's blood pressure is 92/58 mmHg when lying down and 68/40 mmHg when standing. What does this indicate?
A
B
C
D
Test Your Knowledge
A patient has deep, rapid respirations (Kussmaul breathing). Which condition is this pattern most commonly associated with?
A
B
C
D