Aug. 26: Physiology of Vital Signs Response to Exercise

What affects Respiratory Rate?

  • exercise, autonomic NS, environment (temp.)

Changes in Respiration Rate

  • chemical, mechanical, higher brain

  • CO2 increased, Less O2 and decreased pH, aortic bodies gives signals to receptors for INCREASED RESPIRATION

SUM IT UP

  • f

Vital Sign Case

  • g

WHAT ABOUT TEST?

(Objective: Describe physiologic response to various types of exercise and training across systems)

  • You have a patient who had a severe loss of blood, how would you expect his blood pressure to respond in the immediate?

    • Blood pressure would fall

Objective: Describe physiologic response to various types of exercise and training across systems

  • Short answer: (YOU HAVE TO EXPLAIN around 3-4 sentences)

    • You have a patient who had a severe loss of blood, how would you expect his blood pressure to respond in the immediate? Why?

      • I would expect it to drop b/c of the loss of blood volume. Cardiac Output, which consists of HR and Stroke Volume,

Questions/Things to Consider from the Podcast or Text... Clinical thoughts

Understanding Systolic BP and Diastolic BP: Why does Systolic BP do one thing and Diastolic BP do another with exercise?

What about Post-exercise hypotension??

  • Hypertensive versus hypotensive person

What about when load increases for person exercising

What about fit or unfit? Same effort?

  • b

What does what? HR, SV, Vasodilation, Vasoconstriction?

  • g

Feedforward vs. Feedback

  • Feedforward: anticipatory (the body getting ready to do what it knows is coming; anticipating needs before they are actually needed)

  • Feedback: using info. already available to modify (could be negative, could be positive)

Vital Signs

  • HR: increase

  • BP: increase

  • RR: increase

  • (Temp): increase

  • Pain: increase

  • SpO2: about same

  • Waist Circumference: same

  • Gait speed: same

Cardiovascular Response to Exercise

  • Take Home:

    • The body responds to meet the needs of the tissue with an increased cardiac output and increased blood flow to the muscles being used

    • some flux in blood volume depending on how much is sitting in veins (can hold some or not hold to meet body’s needs)

Blood Flow Distribution with Exercise

  • Take home:

    • The body responds to meet the needs of the tissue. There is vasoconstriction in the viscera and capillaries opening in the muscle to shunt blood flow to the muscles being used. Increased open capillaries to the muscle keep available surface area for gas/nutrient exchange high

Heart Rate: How does it change?

  • depends on what you’re doing and how hard you are doing it

Heart Rate with Exercise

  • Take home:

    • The body responds to meet the needs of the tissue by increasing heart rate to support an increased cardiac output and increased blood flow to the muscles being used. Note also the anticipatory rise in HR.

Heart Rate

  • Take home:

    • Heart rate in a fit person tends to be lower than that of an unfit person. Following exercise, heart rate returns to normal more quickly in a fit person.

    • training helps you differently perceive work (lower HR for trained)

Blood Pressure:

  • Rising w/ exercise (Systolic Rises, Diastolic stays the same)

  • Resting BP lower in trained

  • AFTER EXERCISE, expect to see HYPOTENSION (lower)

    • stronger heart

MAP= CO x TPR

  • CO = Stroke Volume x HR

MAP= Diastolic BP + (0.333 (Systolic - Diastolic BP))

Blood Pressure Change w/ Exercise

  • Systolic increases, Diastolic relatively same

    • overall, MEAN increase

  • WITH PROLONGED EXERCISE

    • Take Home:

      • With prolonged exercise (at consistent intensity), cardiac output is maintained, even as stroke volume falls because HR is increased.

Respiration Rate: How does it change?

  • increase rate AND increase in depth

What happens to respiration with submaximal exercise?

  • Take home:

    • The respiratory control center receives input from higher brain centers, chemoreceptors, and mechanoreceptors to make sure that the body’s needs are met.

Response to Activity

  • O2 consumption and CO2 production can increase up to 20-fold

  • Alveolar ventilation and oxygen consumption increase almost step for step (almost 1:1 ratio)

  • The arterial PO2 and pH remain normal

Respiratory Response to Exercise

  • Take home:

    • The respiratory system accommodates to meet the body’s need for oxygen. Thus, during exercise, tidal volume (TV) and/or respiratory rate (RR) increase to meet the increased need for oxygen. In this graphic, both RR and TV increase

Response to Exercise: Alveolar Ventilation and Arterial PCO2

  • Take home:

    • Alveolar ventilation increases immediately in response to exercise. This increase in alveolar ventilation can cause a short-term drop in arterial PCO2. This allows the body to keep a normal acid-base balance

HR and Breathing W/ Exercise

  • large changes (almost 50%)

HR, RR w/ Exercise

O2 Consumption vs. Level of Training

  • Take home:

    • There is a linear relationship between work output and oxygen consumption. (The harder the body works, the more oxygen it needs. An untrained individual maxes out before the trained

Vital Signs Trial

What might a test question look like?

Objective: Describe physiologic response to various types of exercise and training across systems.

  • Your patient, a deconditioned individual, comes to you for an exercise program. You help him begin with a brisk walking program. How would you expect his blood pressure to respond (during)?

    • A. Systolic and diastolic stay the same

    • B. Systolic and diastolic rise

    • C. Systolic and diastolic fall

    • D. Systolic rise, diastolic stay the same

    • E. Diastolic rise, systolic stay the same

    • F. None of the above