John A Wyatt

US Patent:

20140074030, Mar 13, 2014

Filed:

Sep 6, 2013

Appl. No.:

14/019745

Inventors:

David Tseng Ho Hung - Palo Alto CA, US
David Pih - Milpitas CA, US
Purushottam Amarnath Patil - San Diego CA, US
John Michael Wyatt - San Diego CA, US
Vincent James DeFrank - Temecula CA, US

International Classification:

A61M 5/168

US Classification:

604152, 702 47

Abstract:

A pump system and method of detecting/alerting for a possible unintended free flow condition in an administration set includes the steps of a) sampling force signals from a force sensor of the pump at a predetermined frequency; b) storing each of the sampled forces signal in a N-point circular buffer, where N is an integer greater than two; c) calculating a derivative dF/dt based on the two most recent samples; d) repeating step c) and when the most recently calculated derivative dF/dt exceeds a first predetermined threshold, then calculating a N-point moving average of the derivatives dF/dt; and f) when the N-point moving average exceeds a second predetermined threshold, generating a user perceptible alarm to alert the user that a flow stop open condition may have occurred.