Vital Signs

Vital Signs

  • Key Terms: Memorize key terms at the beginning of each chapter as they will be vital in thinking like a nurse. These terms will frequently appear in the course.

Learning Outcomes for Vital Signs

  1. Explain physiological processes regulating body temperature, pulse, respiration, and blood pressure.

  2. Identify factors that influence body temperature, pulse, respiration, and blood pressure.

  3. Know appropriate sites and equipment for measurement and assessment of vital signs including pulse oximetry.

  • Normal Vital Sign Values: Learners should memorize normal ranges for vital signs.

  • Ability to analyze abnormal vital signs critically and identify necessary interventions.

Tips for Exam Preparation

  • Memorize vocabulary at the start of the chapter for effective HESI test preparation.

Definition and Importance of Vital Signs

  • Vital Signs: Include temperature, pulse, respiration, and blood pressure, which are quick, efficient measures of a patient’s overall circulatory, respiratory, neural, and endocrine function.

  • Normal Values:

    • Temperature: 37.0°C (98.6°F)

    • Pulse: 60-100 bpm

    • Respirations: 12-20 breaths/min

    • Blood Pressure: 120/80 mmHg

    • Pain: 0-10 scale (5th vital sign)

    • Pulse Oximetry: ≥ 95%

  • Significance: Vital signs reflect physiological functioning and overall health. Although other personnel can measure them, nurses are responsible for ensuring accurate measurements.

Guidelines for Measuring Vital Signs (Part 1)

  • Measuring vital signs is a nurse's responsibility:

    • Clean all equipment between patients.

    • Ensure that equipment is functioning properly.

    • Choose appropriate equipment based on patient needs.

    • Be aware of the patient’s baseline vital signs.

    • Understand the patient's health history and any medications taken.

    • Control environmental factors impacting measurements.

Guidelines for Measuring Vital Signs (Part 2)

  • Use a systematic approach for consistency.

  • Collaborate on how often to assess.

  • Use findings to make decisions regarding medication administration.

  • Analyze results considering the patient’s condition and communicate significant changes.

  • Provide education for the patient regarding vital signs and their analysis.

When to Take Vital Signs

  • On admission to healthcare facilities.

  • According to specific institutional policies.

  • Any change in the patient's condition.

  • Following a loss of consciousness.

  • Pre- and post-surgical or invasive procedures.

  • After activities that pose risks, such as ambulation post-surgery.

  • Before administering medications that affect cardiovascular and respiratory function.

Body Temperature

  • Defined as the balance between heat production and heat loss measured in degrees.

Heat Transfer Mechanisms

  • Radiation: Heat emitted from the body.

  • Conduction: Transfer of heat to another object.

  • Convection: Heat loss through airflow.

  • Evaporation: Liquid converting to vapor (e.g., sweating).

  • Diaphoresis: Severe sweating concentrated on forehead and upper thorax.

Body Heat Regulation

  • Hypothalamus: Main control center for temperature regulation.

  • Skin: Major site for heat loss.

  • Elevated temperatures impact other vital signs, including pulse and respiration.

Nursing Interventions for Elevated Temperature

  • Independent Interventions:

    • Modify the environment (cool sponges, blankets).

    • Increase oral fluid intake, provide simple carbohydrates to prevent tissue breakdown.

  • Dependent Interventions: Administer fever reducers and anti-infectives as ordered.

Factors Affecting Body Temperature

  • Circadian Rhythms: Temperature is lower in the morning, higher in late afternoon.

  • Age and Gender: Elderly have lower body temperatures.

  • Physical Activity: Increases body temperature.

  • Health State: Disease processes can alter temperature.

  • Environmental Temperature: Risks of hypo- or hyperthermia.

Measuring Body Temperature

  • Thermometers: Various types include electronic, tympanic, and temporal artery.

    • **Common Routes:

      • Oral: 37.0°C (98.6°F)

      • Rectal: 37.5°C (99.5°F)

      • Axillary: 36.5°C (97.7°F)

      • Tympanic: 37.5°C (99.5°F)

      • Forehead: 34.4°C (94.0°F)**

    • Understand measurement conversions.

Pulse

  • Pulse Rate: Number of contractions in a peripheral artery per minute.

    • Bradycardia: Low heart rate (<60 bpm).

    • Tachycardia: High heart rate (100-180 bpm).

  • Factors Influencing Pulse Rate:

    • Age/Sex Stats: Women's heart rates are typically higher.

    • Physical Activity: Increases heart rate; athletes generally have lower rates.

    • Health Conditions: Fever and stress raise heart rate.

    • Medications: May alter pulse rate.

    • Diseases: Various conditions affect heart rate.

Assessing Peripheral Pulses

  • Equipment Used: Fingers, stethoscope, doppler ultrasound.

  • Rate Assessment: Regular, tachycardia, bradycardia (compare left and right pulses).

  • Amplitude Qualifiers:

    • 0: Absent

    • 1+: Diminished

    • 2+: Normal

    • 3+: Full/Strong

    • 4+: Bounding

  • Stroke Volume: Volume of blood with each heartbeat (CO = SV x Pulse).

Respirations

  • Ventilation: Air movement in/out of lungs, either autonomic or voluntary.

Physiology of Respiration

  • Respiratory center activated by blood CO2 levels.

  • Breathing Mechanics: Inhalation (breathing in) and Exhalation (breathing out).

  • Diffusion: Gas exchange between alveoli and blood cells.

  • Perfusion: Distribution of red blood cells in pulmonary capillaries.

Assessing Respirations

  • Factors to note:

    • Rate: 12-20 breaths/min (adults).

    • Depth: Characteristics of breaths.

  • Causes for Changes in Respiratory Rates:

    • Increased rate (tachypnea): Cells needing more oxygen or CO2 build-up.

    • Decreased rate (bradypnea): Increase in intracranial pressure, opioids, or poor positioning.

Common Respiratory Terms

  • Eupnea: Normal, unlabored breathing.

  • Tachypnea: Increased rate; response to metabolism.

  • Bradypnea: Decreased rate; often pathological.

  • Dyspnea: Difficult/labored breathing.

  • Orthopnea: Changes in breathing when seated.

  • Cheyne-Stokes: Cycle of increasing and decreasing breaths with apnea.

  • Kussmaul’s Respirations: Increased rate and depth (hyperventilation).

Pulse Oximetry

  • Definition: Percentage of hemoglobin bound to oxygen in the arteries.

  • Assessment Locations: Fingers, earlobes, toes, forehead.

Factors Leading to Poor Readings:

  • Improper positioning, inadequate hemoglobin levels.

Blood Pressure (BP)

  • Definition: Force of circulating blood against artery walls.

  • Components:

    • Systolic: Pressure during heart contractions.

    • Diastolic: Pressure during heart relaxation.

  • Normal BP Ranges:

    • Normal: <120/<80

    • Elevated: 120-129/<80

    • HTN Stage 1: 130-139/80-89

    • HTN Stage 2: >140/>90

    • Hypertensive Crisis: >180/>120

Factors Affecting Blood Pressure

  • Age, Gender, Race: Natural variations.

  • Circadian Rhythms: Daily BP fluctuations.

  • Diet: BP typically rises post meals.

  • Exercise and Weight: Obesity often correlates with higher BP.

  • Emotional State: BP rises with heightened emotions.

  • Body Position: Lying down often lowers BP.

Orthostatic Vital Signs

  • Orthostatic Hypotension Defined: Also called postural hypotension, it's when BP drops when a patient stands.

  • Assessment Protocol: Measure BP in lying, sitting, and standing positions.

Techniques for Assessing Blood Pressure

  • Equipment Needed: Stethoscope and sphygmomanometer.

  • Korotkoff Sounds: Sounds observed during BP measurement; first sound is systolic, cessation marks diastolic.

  • Common Sites: Brachial and popliteal arteries.

Tips for Accurate Blood Pressure Readings

  • Ensure quiet environment, accurately take the measurement, and reflect on any potential errors affecting accuracy.

  • Consider factors like cuff size, placement, and surroundings.

Patient Teaching for Blood Pressure Management

  1. Educate about normal values and when to report abnormalities.

  2. Ensure BP is taken without clothing over the arm.

  3. Encourage sitting with back straight, feet flat, and no crossed legs.

  4. Stress the importance of consistently measuring BP at the same time daily.

  5. Take multiple readings and record results thoughtfully.