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Simplified method to measure respiratory-related changes in arterial pulse pressure in patients receiving mechanical
Capucine Morélot-Panzini1, Yannick Lefort, Jean-Philippe Derenne
1Laboratoire de Physiopathologie Respiratoire et Unité de Réanimation, Service de Pneumologie, Groupe Hospitalier Pitié-Salpêtrière, Assistance Publique-Hôpitaux de Paris, Paris, France.
Study Objectives:
Measuring respiratory-related changes in arterial pulse pressure is useful to guide fluid expansion in hemodynamically compromised patients. In the absence of automation, this can be uneasy in clinical practice. The objective of this study was to test an alternative approach (expiratory pause) that should be easier to apply.
Design:
Prospective observational study comparing two measurement methods of a biological variable.
Patients:
Seventeen patients receiving mechanical ventilation without spontaneous respiratory activity, with an arterial indwelling catheter, exhibiting respiratory-related fluctuations in arterial pressure.
Setting:
Ten-bed respiratory ICU in a 2,000-bed university hospital.
Intervention:
Analysis of clinically gathered data without specific experimental intervention.
Measurements:
Determinations of the change in arterial pulse pressure observed during ventilatory cycling (Delta Pp,dyn) ["dynamic"] and change in arterial pulse pressure observed during expiratory pauses (Delta Pp,stat) ["static"] were performed to assess respiratory mechanics, and comparison of the two sets of data (correlation, Bland and Altman, Passing and Bablok regression).
Results:
Delta Pp,dyn and Delta Pp,stat were strongly correlated (R = 0.964; 95% confidence interval, 0.917 to 0.987; p < 0.0001), with a good level of agreement (mean difference, 0.016; lower limit of agreement, - 0.087; upper limit, 0.120) and no systematic difference.
Conclusion:
Measuring respiratory-related Delta Pp,stat provides data that seem interchangeable with Delta Pp,dyn, providing an easy means to routinely obtain this information.
Related Concept Videos
Assessment of Ventilation I: Respiratory Rate
A Ventilation assessment is critical for monitoring a patient's health status. Respiration, one of the most accessible vital signs, provides insights into the function of numerous body systems and can indicate serious health issues, such as brainstem injuries from head trauma.
Critical Guidelines for Assessing Ventilation:
Special considerations while measuring oxygen saturation
Ensuring accuracy in vital sign recordings while prioritizing patient comfort and minimizing anxiety is important.
Sites for measuring blood pressure
The Brachial Artery: Primary Site for Blood Pressure Measurement
Assessment of blood pressure in brachial artery(two-step method)
Assessment of Ventilation II: Respiratory Depth and Rhythm
Respiratory depth measures the volume of air inhaled or exhaled during a breath. It can vary from shallow to deep and typically remains consistent when a person is at rest or asleep. Occasionally, individuals will automatically inhale deeply, known as sighing, which inflates the lungs with more air than normal breathing.
To assess respiratory depth, observe the degree of chest excursion or movement:
Measurement of Blood Pressure

