Lesson 12: Pulse Contour Analysis Summary

Lesson 12: Pulse Contour Analysis Overview

  • Measures preload responsiveness through various methods:

    • Plethysmography Variability Index (requires pulse oximeter)

    • Stroke Volume Variation (requires esophageal Doppler)

    • Systolic Pressure Variation (requires direct arterial pressure)

    • Pulse Pressure Variation (requires arterial pressure)

Conditions for Accurate Measurement

  • Requires positive pressure ventilation for accuracy.

  • Hypovolemia increases stroke volume variation due to intrathoracic pressure effects.

Clinical Implications

  • Preload responsiveness indicated by a ≥ 10% increase in stroke volume (SV) upon administration of 200-250 mL fluid.

  • A calculated fluid responsiveness threshold of 13-15% in dynamic measures predicts volume responsiveness.

Administration of Fluids

  • Monitor SV changes with fluid boluses:

    • If SV increases > 10%, consider further 200-250 mL boluses.

    • Maximize fluid therapy until SV changes < 10% (optimal Starling curve position).

  • If plateau is reached, assess other interventions (vasoactive drugs) if hypotension occurs.

Limitations of Pulse Contour Analysis

  • Several factors can reduce accuracy:

    • Spontaneous ventilation

    • Small tidal volume

    • PEEP

    • Open chest

    • Right ventricular dysfunction

    • Dysrhythmias