Reperfusion protection in resuscitation

• US 9,457,165 B2
• Filed: 02/03/2011
• Issued: 10/04/2016
• Est. Priority Date: 01/24/2006
• Status: Active Grant

• Current Assignee: Zoll Medical Corporation (Asahi Kasei Corporation)
• Original Assignee: Zoll Medical Corporation (Asahi Kasei Corporation)
• Inventors: Freeman, Gary A.
• Primary Examiner(s): Yu, Justine
• Assistant Examiner(s): Louis, LaToya M
• Application Number:
  US13/020,096
• Publication Number:
  US 20110120471A1
• Time in Patent Office: 2,070 Days
• Field of Search: 128/203.12, 128/203.14, 128/203.25, 128/204.23, 128/204.21, 128/205.11
• US Class Current: 1/1
• CPC Class Codes: A61M 16/0081 Bag or bellow in a bottle
• CPC Class Codes: A61M 16/12 by mixing different gases
• CPC Class Codes: A61M 16/202 electrically actuated
• CPC Class Codes: A61M 2016/0413 with detectors of CO2 in exhaled gases
• CPC Class Codes: A61M 2202/0007 introduced into the body
• CPC Class Codes: A61M 2202/0225 Carbon oxides, e.g. Carbon dioxide
• CPC Class Codes: A61M 2205/502 User interfaces, e.g. screens or keyboards
• CPC Class Codes: A61M 2230/005 Parameter used as control input for the apparatus
• CPC Class Codes: A61M 2230/202 partial carbon oxide pressure, e.g. partial dioxide pressure (P-CO2)
• CPC Class Codes: A61M 2230/208 pH-value
• CPC Class Codes: A61M 2230/40 Respiratory characteristics

Abstract

An apparatus and method for resuscitating a patient suffering from cardiac arrest or another condition in which normal circulation has been interrupted. A ventilator is used for delivering a gas mixture to the patient. The ventilator is configured to adjust the partial pressure of CO2 to one or more partial pressures high enough to slow expiration of CO2 from the patient'"'"'s lungs and thereby maintain a reduced pH in the patient'"'"'s tissues for a period of time following return of spontaneous circulation.

Claims

1. Apparatus for resuscitating a patient suffering from cardiac arrest or another condition in which normal circulation has been interrupted, the apparatus comprising:

a ventilator for applying to the patient;

the ventilator being configured to deliver a gas mixture to the patient,

wherein the ventilator comprises at least one first sensor, associated processing, and memory configured to measure CO₂ concentration in an airway of the patient and, based on a comparison of at least two measurements of CO₂ concentration in the airway, determine that return of spontaneous circulation (ROSC) has occurred,

wherein the processor and the associated memory are further configured so that after the determination of the return of spontaneous circulation, the partial pressure of CO₂ is automatically adjusted to one or more partial pressures high enough to slow expiration of CO₂ from the patient'"'"'s lungs and thereby maintain a reduced pH in the patient'"'"'s tissues for an automatically determined period of time following the determination of the return of spontaneous circulation (ROSC), and

wherein the processor is configured to adjust the partial pressure of CO2 to be higher than ambient CO2 partial pressure during the automatically determined period of time.

2. The apparatus of claim 1 wherein adjustment of the partial pressure of CO₂ includes adding CO₂ to the gas inspired by the patient.

3. The apparatus of claim 1 wherein adjustment of the partial pressure of CO₂ has an effect of maintaining the pH of the patient'"'"'s tissues below 7.0 for the period of time following the return of spontaneous circulation.

4. The apparatus of claim 1 further comprising a second sensor and associated processing for determining the pH of the patient'"'"'s tissue, and automatically adjusting the partial pressure of CO₂ at least in part in response to the pH of the patient'"'"'s tissue.