Chapter 10 - Vital Signs

Vital Sign Significance

• Vital signs are objective measurements of the body's basic functions.
• They include temperature, blood pressure, pulse, respiratory rate, and oxygen saturation.
• Normal ranges vary based on factors like age, BMI, and gender.
• Vital signs monitor patient health and detect deterioration, especially in acute care.

Assessment Techniques & Equipment

Temperature

• Oral: Convenient, commonly used, electronic thermometers (20-30 seconds).
• Rectal: Most accurate, invasive, patient positioned in left lateral decubitus.
• Tympanic: Noninvasive, quick, for adults, pull ear up and back; children under 3, pull ear down and back.
• Temporal Artery: Sliding probe across forehead/behind ear, less accurate.

Pulse

• Measures the heart's pumping action, felt as a pressure wave.
• Palpate radial pulse using first three fingers at the wrist.
• Count beats for 30 seconds (multiply by 2 for regular rhythm), 60 seconds (for irregular rhythm).
• Assess rate, rhythm, and force. Auscultate heart sounds if irregularities are detected.
• Normal rates vary by age and gender (faster in infancy/childhood, slightly faster in females after puberty).

Respiration Rate

• Normal breathing is relaxed, regular, automatic, and silent.
• Count for 60 seconds for accuracy.
• Document rate per minute and breathing characteristics.

Blood Pressure

• Force of blood against vessel walls, changes with cardiac cycle.
• Systolic: Maximum pressure during contraction.
• Diastolic: Resting pressure between contractions.
• Pulse Pressure: Difference between systolic and diastolic.
• Mean Arterial Pressure (MAP): Average pressure forcing blood into tissues (MAP > 60 mmHg needed for adequate perfusion).
• Normal readings vary based on age, sex, race, social determinants, daily patterns, weight, exercise, emotions, and stress.
• Noninvasive: Electric devices, measures BP, MAP, and pulse rate.
• Manual: Sphygmomanometer and stethoscope, able to assess pulse quality.
• Proper technique crucial for accurate readings including a 5-minute rest, sitting position, uncrossed legs, and arms at heart level, correct cuff size.
• Document extremity used, position, and cuff size for consistency.
• Normal BP < 120 mmHg / < 80 mmHg

Oxygen Saturation (SpO2)

• Noninvasive, measures arterial blood oxygen saturation.
• Measured on fingers, forehead, nose, or toes (adults); hands, thumbs, or feet (infants).
• Normal range is 97% to 99%.

Doppler

• Used to measure blood flow through vessels.
• Detects and amplifies changes in sound frequencies as blood flows and ebbs.
• Useful for locating peripheral pulse sites.

Abnormal Vital Signs

• Bradycardia: Heart rate < 60 bpm
• Tachycardia: Heart rate > 100 bpm
• Tachypnea: Respiratory rate > 25 breaths/min
• Bradypnea: Respiratory rate < 12 breaths/min
• Hypertension: Systolic > 140 mmHg or diastolic > 90 mmHg
• Hypotension: Low blood pressure, 20 mmHg decrease or diastolic drop >10 mmHg in a standing position.

Orthostatic Vital Signs

• Serial measurements of pulse and blood pressure.
• Useful in volume depletion suspicion, known hypertension/antihypertensive medication use, syncope/near-syncope reports.
• Procedure:
  • Patient rests supine 3-5 minutes, measure BP and pulse.
  • Have patient sit, measure BP and pulse.
  • Have patient stand, measure BP and pulse.
  • After standing 3 minutes, measure BP and pulse.
• Normally, a slight decrease in reading when changing from supine to standing is expected.