PATIENT MONITORING SYSTEM

• US 20140163402A1
• Filed: 03/15/2013
• Published: 06/12/2014
• Est. Priority Date: 06/21/2011
• Status: Active Grant

• Current Assignee: Masimo Corporation
• Original Assignee: Cercacor Laboratories
• Inventors: Lamego, Marcelo M., Kiani, Massi Joe E., Poeze, Jeroen, Dalvi, Cristiano, Vo, Hung
• Granted Patent: US 9,986,919 B2
• Time in Patent Office: Days
• US Class Current: 600/493
• CPC Class Codes: A61B 2560/0214 of power generation or supply
• CPC Class Codes: A61B 5/02141 Details of apparatus construction, e.g. pump units or housings therefor, cuff pressurising systems, arrangements of fluid conduits or circuits A61B5/02233, A61B5/0235 take precedence
• CPC Class Codes: A61B 5/022 by applying pressure to close blood vessels, e.g. against the skin; Ophthalmodynamometers
• CPC Class Codes: A61B 5/02225 using the oscillometric method
• CPC Class Codes: A61B 5/02233 Occluders specially adapted therefor tourniquets A61B17/132
• CPC Class Codes: A61B 5/0225 the pressure being controlled by electric signals, e.g. derived from Korotkoff sounds
• CPC Class Codes: A61B 5/0235 Valves specially adapted therefor
• CPC Class Codes: A61B 5/6824 Arm or wrist
• CPC Class Codes: A61B 5/6828 Leg
• CPC Class Codes: A61B 5/72 Signal processing specially adapted for physiological signals or for diagnostic purposes character recognition, recognising digital ink, document-oriented image-based pattern recognition G06V30/00; recognition or understanding of postal images G06V30/424
• CPC Class Codes: A61B 5/7221 Determining signal validity, reliability or quality A61B5/7207 and A61B5/7217 take precedence
• CPC Class Codes: A61B 5/725 using specific filters therefor, e.g. Kalman or adaptive filters A61B5/316 take precedence

Abstract

A patient monitoring system includes an inflatable cuff, a gas reservoir containing a compressed gas, and a sensor. When the inflatable cuff is coupled to a wearer, the gas reservoir supplies gas to the inflatable cuff to inflate the inflatable cuff via gas pathways. As the inflatable cuff inflates, a patient monitor can receive blood pressure data from the sensor and use the blood pressure data to determine the blood pressure of the wearer. The patient monitor can also receive blood pressure data during deflation of the inflatable cuff to determine the blood pressure of the wearer.

Claims

1-77. -77. (canceled)

78. A patient monitoring system comprising:

an inflatable cuff attachable to a wearer;

a gas reservoir coupled to the inflatable cuff and configured to provide gas to the inflatable cuff via a gas pathway;

a sensor configured to obtain blood pressure data from the inflatable cuff; and

a patient monitor coupled to the inflatable cuff and configured to receive the blood pressure data from the sensor to determine a blood pressure measurement of the wearer.

79. The patient monitoring system of claim 78, wherein the gas is compressed gas.

80. The patient monitoring system of claim 78, wherein the gas reservoir comprises at least one of a gas tank, a gas cylinder, and a bottled gas and at least one of a pre-filled gas and compressed gas.

81. The patient monitoring system of claim 78, wherein the gas reservoir is replaceable.

82. The patient monitoring system of claim 78, further comprising a valve associated with the gas pathway and configured to open to allow gas to flow from the gas reservoir to the inflatable cuff.

83. The patient monitoring system of claim 82, further comprising:

a chamber coupled to the valve; and

a chamber cover hingedly coupled to the chamber, wherein when the chamber cover is closed the chamber cover and the chamber encapsulate the gas reservoir and the chamber cover exerts a force on the gas reservoir in the direction of the valve.

84. The patient monitoring system of claim 78, wherein the valve comprises a three-way valve and is configured to allow gas to flow from the gas reservoir to the inflatable cuff when in a first configuration and further configured to allow gas to exit the inflatable cuff when in a second configuration.

85. The patient monitoring system of claim 78, further comprising a two-stage regulator configured to maintain the pressure in a segment of the gas pathway at an approximately constant pressure.

86. The patient monitoring system of claim 78, wherein the patient monitor is configured to filter the blood pressure data to generate filtered blood pressure data.

87. The patient monitoring system of claim 86, wherein the filtered blood pressure data comprises pressure oscillations in the inflatable cuff due to blood flow in an artery of the wearer.

88. The patient monitoring system of claim 78, wherein the gas from the gas reservoir is used to generate electricity for the patient monitoring system.

89. The patient monitoring system of claim 78, wherein the sensor is a pressure sensor.

90. The patient monitoring system of claim 78, further comprising a valve, wherein the valve comprises:

a body having an input nozzle defining an input port;

a cap having an output nozzle defining an output port;

an actuator disposed between the body and the cap,

the actuator having an open position that allows gas flow from the input port to the output port and a closed position that prevents gas flow from the input port to the output port,

the actuator having an SMA wire loop in communication with an electrical plug, and

the SMA wire loop contracting and expanding in response to current applied to the electrical contacts so as to move the actuator between the closed position and the open position.

91. The patient monitoring system of claim 90, wherein the actuator comprises:

a plunger having a seal end and a spring end.

a seal disposed at the seal end,

the seal configured to press against a seat disposed in the body proximate the input port so as to prevent gas flow through the input port in the closed position;

a spring disposed at the spring end,

the spring biasing the seal against the seat;

the SMA wire loop having a closed end strung through the plunger and open ends fixedly secured proximate the cap,

the SMA wire loop pulls the actuator against the force of the spring when current flows through the electrical contacts so as to move the seal away from the seat as the actuator moves from the closed position to the open position.

92. The patient monitoring system of claim 91, wherein the plunger comprises:

a cylindrical piston;

a plurality of semi-cylindrical rails disposed around the walls of the piston.

93. The patient monitoring system of claim 92, wherein the body comprises:

a generally elongated hollow shell having an closed first end defining the input nozzle and a generally open second end that receives the cap;

a generally square cross-sectioned exterior defining edges; and

a fluted interior that accommodates the actuator.

94. The patient monitoring system of claim 93, wherein the body fluted interior comprises:

a plurality of semi-cylindrical grooves proximate the shell edges; and

a plurality of partially-cylindrical grooves proximate the shell sides,

the semi-cylindrical grooves receive the plunger rails which slidably fit within the grooves,

the partially-cylindrical grooves receive the relatively smaller-diameter plunger piston so as to define gas channels that accommodate gas flow between the input port of the body and the output port of the end cap when the seal is pulled away from the seal seat by the SMA wire in opposition to the spring during valve actuation.

95. The patient monitoring system of claim 78, wherein the sensor is a pressure sensor responsive to a predetermined gas pressure threshold so as to create a conductive path across sensor contacts, the pressure sensor comprising:

a sensor housing having an external nozzle defining a nozzle aperture;

a chamber defined within the housing;

the aperture extending from the nozzle to the chamber;

a plurality of electrical contacts partially disposed within the chamber and extending from the chamber to a terminus external to the housing;

a flexible conductive element disposed within the chamber proximate the contacts;

the conductive element responsive to gas pressure exerted at the nozzle and translated into the chamber via the nozzle aperture so as to cause the conductive element to bridge the electrical contacts;

the electrical contacts configured to conduct current when bridged by the conductive element so as to indicate a gas pressure threshold at the nozzle.