What question did this study set out to answer?

This study investigates how cardiac glycosides affect hemodynamics in normal individuals during rest and exercise.

November 1, 1958Journal of Applied Physiology

Hemodynamic Effects of Cardiac Glycosides on Normal Human Subjects During Rest and Exercise

View Full Paper

Ask AI

Bookmark

Why the study?

What are the hemodynamic effects of intravenous cardiac glycosides on normal human subjects during rest and exercise?

Population

11 normal human subjects (8 in the main study, 3 in the verification study)

Comparison

Intravenous administration of 1.0-1.2 mg of… vs Baseline measurements before administration

Design

Other

Authors

MWM. Henry WilliamsGrant Medical Center LZLenore R. ZohmanUniversity of Vermont ARArnold C. RatnerNational Institutes of Health

Discussion

Member takes

Implication

May caution against assuming inotropic benefit in normals; leaves open net effects in heart failure.

Key Points

This study investigates how cardiac glycosides affect hemodynamics in normal individuals during rest and exercise.
Eight normal subjects were tested for hemodynamics using the dye dilution technique and strain gauges.
Measurements were taken at rest and during exercise before and after administering digitalis (digoxin or acetyl strophanthidin).
Blood pressure changes were verified with additional injections of acetyl strophanthidin and control saline.
At rest, cardiac output decreased by an average of 12% and blood pressure increased from 95 mm Hg to 109 mm Hg after digitalization.
During exercise, cardiac output decreased by an average of 18%, with no change in blood pressure following digitalization.
Systemic vascular resistance increased following digitalization in both resting and exercising states.

Structured PICO

What are the hemodynamic effects of intravenous cardiac glycosides on normal human subjects during rest and exercise?

Population

11 normal human subjects (8 in the main study, 3 in the verification study)

Intervention

Intravenous administration of 1.0-1.2 mg of digoxin or 1.6-1.8 mg of acetyl strophanthidin

Comparator

Baseline measurements before administration (and control saline injection in 3 verification subjects)

Outcome

Hemodynamic changes (cardiac output, pulse rate, stroke volume, blood pressure, systemic vascular resistance) at rest and during exercisesurrogate

In normal human subjects, the peripheral vasoconstrictive action of cardiac glycosides overshadows any positive inotropic effects, leading to increased systemic vascular resistance and decreased cardiac output.

Cite This Study

Williams et al. (1958) studied this question.

synapsesocial.com/papers/6a20232ceaa49a33b5fbf3b2 https://doi.org/10.1152/jappl.1958.13.3.417

View Full Paper

Ask AI

Bookmark

Hemodynamic Effects of Cardiac Glycosides on Normal Human Subjects During Rest and Exercise

Discussion

Member takes

Implication

Key Points

Structured PICO

Cite This Study

Hemodynamic Effects of Cardiac Glycosides on Normal Human Subjects During Rest and Exercise

Discussion

Member takes

Implication

Key Points

Structured PICO

Cite This Study

Also Consider

Also Consider