Horowitz index

From WikiMD's Food, Medicine & Wellness Encyclopedia

Horowitz Index is a medical term used to measure the severity of pulmonary embolism. It is named after Dr. Horowitz, who first introduced the concept. The Horowitz Index is calculated by dividing the arterial oxygen pressure (PaO2) by the fraction of inspired oxygen (FiO2).

Calculation[edit | edit source]

The Horowitz Index is calculated using the following formula:

<math>\text{Horowitz Index} = \frac{\text{PaO2}}{\text{FiO2}}</math>

Where:

  • PaO2 is the partial pressure of oxygen in arterial blood, measured in millimeters of mercury (mmHg).
  • FiO2 is the fraction of inspired oxygen, expressed as a decimal.

Clinical Significance[edit | edit source]

The Horowitz Index is used in the diagnosis and management of Acute Respiratory Distress Syndrome (ARDS). A Horowitz Index of less than 200 is indicative of severe ARDS, while a value of less than 300 indicates moderate ARDS.

Limitations[edit | edit source]

While the Horowitz Index is a useful tool in the management of ARDS, it has its limitations. It does not take into account the patient's age, comorbidities, or the cause of the ARDS. Furthermore, it is not a direct measure of lung function, but rather a measure of the efficiency of oxygen transfer in the lungs.

See Also[edit | edit source]

References[edit | edit source]

  • Horowitz, J. (1974). "A simple index of lung function". New England Journal of Medicine. 291 (10): 506–507.
Horowitz index Resources
Doctor showing form.jpg
Wiki.png

Navigation: Wellness - Encyclopedia - Health topics - Disease Index‏‎ - Drugs - World Directory - Gray's Anatomy - Keto diet - Recipes

Search WikiMD


Ad.Tired of being Overweight? Try W8MD's physician weight loss program.
Semaglutide (Ozempic / Wegovy and Tirzepatide (Mounjaro) available.
Advertise on WikiMD

WikiMD is not a substitute for professional medical advice. See full disclaimer.

Credits:Most images are courtesy of Wikimedia commons, and templates Wikipedia, licensed under CC BY SA or similar.


Contributors: Admin, Prab R. Tumpati, MD