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The free energy change for a reaction that occurs under the standard conditions of 1 bar pressure and at 298 K is called the standard free energy change. Since free energy is a state function, its value depends only on the conditions of the initial and final states of the system. A convenient and common approach to the calculation of free energy changes for physical and chemical reactions is by use of widely available compilations of standard state thermodynamic data. One method involves the...
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Drosophila Adult Olfactory Shock Learning
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Calculated decisions: Shock index

Kamal Medlej1

  • 1Department of Emergency Medicine, Massachusetts General Hospital, Boston, MA

Emergency Medicine Practice
|June 1, 2019
PubMed
Summary
This summary is machine-generated.

The shock index, a ratio of heart rate to blood pressure, can better detect hidden shock in trauma and hemorrhage patients than vital signs alone.

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Area of Science:

  • Emergency Medicine
  • Critical Care Medicine
  • Physiology

Background:

  • Occult shock, a state of critical hypoperfusion not immediately apparent from vital signs, poses a diagnostic challenge.
  • Traditional vital signs like heart rate and blood pressure have limitations in identifying early or compensated shock.
  • Trauma and acute hemorrhage are high-risk scenarios where early shock detection is crucial for patient outcomes.

Purpose of the Study:

  • To evaluate the diagnostic utility of the shock index in identifying occult shock.
  • To compare the sensitivity of the shock index against heart rate and blood pressure alone in specific patient populations.

Main Methods:

  • Retrospective analysis of patient data including heart rate, blood pressure, and clinical outcomes.
  • Calculation of the shock index (heart rate divided by systolic blood pressure).
  • Comparison of the shock index's performance with individual vital signs in detecting occult shock.

Main Results:

  • The shock index demonstrated higher sensitivity in detecting occult shock compared to heart rate or blood pressure alone.
  • This enhanced sensitivity was particularly noted in patients presenting with trauma or acute hemorrhage.
  • Elevated shock index values correlated with increased likelihood of occult shock.

Conclusions:

  • The shock index serves as a valuable and sensitive early warning indicator for occult shock.
  • Clinicians should consider utilizing the shock index in the initial assessment of patients with trauma or acute hemorrhage.
  • The shock index may facilitate earlier intervention and improve management of shock.