Method of measuring transcutaneous access blood flow
US6746407B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 29, 2000 |
| Grant date | Jun 8, 2004 |
| Priority date | — |
| Expiry date | Jan 9, 2021 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61M1/3656
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
Indicator dilution techniques are used to measure vascular access flow rates during routine hemodialysis. A bolus injection port is used to infuse a specific volume (Vi) of an indicator diluent, such as saline or dye, into the patient cardiovascular circuit by one of the following:1. Needle injection of a known volume (bolus) of indicator diluent directly into the access site in the presence or absence of the hemodialysis circuit.2. Infusion of an indicator diluent into the arterial, venous line upstream of the venous needle.3. Turning the ultrafiltration of the dialysis delivery system from OFF to ON and OFF again over a predetermined time period.4. In a hemodialysis circuit, turning on the hemodialysis pump and using the priming saline volume as a single saline bolus.A transdermal sensor is used to measure the percent change in a blood parameter. The sensor is positioned directly over the vascular access site a prescribed distance downstream of the injection site and upstream of the access-vein connection. The sensor employs emitter and detector elements at multiple spacings (d1, d2) for the purpose of measuring the bulk absorptivity (&agr;) of the area immediately surrounding an…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.