Perfusion ratio detector
US4424814A · kind A · utility
Inventor
Key dates
| Filing date | Mar 30, 1981 |
| Grant date | Jan 10, 1984 |
| Priority date | — |
| Expiry date | Mar 30, 2001 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B8/4236
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
The detector provides an effective means of non-invasively monitoring the perfusion of blood by external cardiac massage during a cardiac arrest. A Doppler probe is adhesively placed on the patient's skin, preferably to sense the carotid pulse which has been found as the most significant indicator of sufficient cerebral perfusion. The electronic part of the detector measures both the period of blood flow (T.sub.f), and the period of the external cardiac massage (ECM) cycle (T.sub.ecm). The electronic components comprise a flow detector such as a Doppler sensor and Schmidtt trigger, a rate converter such as a frequency to voltage converter feeding a voltage controlled oscillator, and a counter and display. The preferred display is a series of ten light indicators for demarcating perfusion ratio in 10% increments.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.