Techniques and devices for extending a piston, for example connected to a medical device such as a mechanical CPR device, to accommodate different sized patients, are described herein. In some cases, a piston of a mechanical CPR device may include an inner piston at least partially slidable into an external piston sleeve. In one aspect, an external piston spacer may be attached to an outward surface of the inner piston to extend the length of the piston. In another aspect an internal bayonet sleeve may contact one or more locking rods at various positions, enabling adjustment of the length of the inner piston. In yet another aspect, a piston adapter may be removably attached to the end of the piston. In all aspects, the change in length of the piston may be detected and used to modify movement of the piston, for example to more safely perform mechanical CPR.

A CPR machine (100) is configured to perform, on a patient's (182) chest, compressions that alternate with releases. The CPR machine includes a compression mechanism (148), and a driver system (141) configured to drive the compression mechanism. A force sensing system (149) may sense a compression force, and the driving can be adjusted accordingly if there is a surprise. For instance, driving may have been automatic according to a motion-time profile, which is adjusted if the compression force is not as expected (850). An optional chest-lifting device (152) may lift the chest between the compressions, to assist actively the decompression of the chest. A lifting force may be sensed, and the motion-time profile can be adjusted if the compression force or the lifting force is not as expected.

Among other things, in one aspect, we describe a system for assisting with cardiopulmonary resuscitation (CPR). The system includes at least one sensor; and one or more processors configured for calculating a chest compliance relationship based on data received from the at least one sensor, and determining a neutral position of chest compression based at least in part on a feature of the chest compliance relationship. The system can take the form of an active compression-decompression device.

Systems and methods related to the field of cardiac resuscitation, and in particular to devices for assisting rescuers in performing cardio-pulmonary resuscitation (CPR) are described herein. The system includes an applicator device configured to provide ACD CPR treatment to a patient's chest according to a plurality of phases at least one sensor configured to be coupled to the patient's chest and to measure at least one parameter related to the ACD CPR treatment and information for determining whether at least one transition point of the ACD CPR treatment has been reached; and one or more processors configured to provide a feedback signal based on a parameter for administering ACD CPR treatment to the patient's chest according to a desired treatment protocol.

A method for performing cardiopulmonary resuscitation (CPR) includes elevating the heart of an individual to a first height relative to a lower body of the individual. The lower body may be in a substantially horizontal plane. The method may also include elevating the head of the individual to a second height relative to the lower body of the individual. The second height may be greater than the first height. The method may further include performing one or more of a type of CPR or a type of intrathoracic pressure regulation while elevating the heart and the head. The first height and the second height may be determined based on one or both of the type of CPR or the type of intrathoracic pressure regulation.

A mechanism attached to a mechanical CPR device can be automatically attached to the patient's torso. The mechanical CPR device can extend the mechanism to a first position at which the mechanism comes into contact with the patient's torso. The mechanism can be further extended until a first threshold is reached. The mechanism can be retracted to the first position. The mechanism can be further retracted from the first position until a second threshold is exceeded. The mechanism can then be extended to a second point at which the second threshold is no longer exceeded. The mechanism may comprise a suction cup or sticker plate, and may be attached to an end of a piston of the mechanical CPR device.

Systems and apparatuses related to the field of cardiac resuscitation, and in particular to devices for assisting rescuers in the administration of cardio-pulmonary resuscitation (CPR) are described herein. The system includes an adhesive pad configured to be adhered to at least a portion of a patient's chest, a sensor configured to be placed on the patient's chest and to measure at least one chest compression parameter during CPR treatment, and a landing pad having a coupling surface at least partially surrounding the sensor and configured for maintaining adherence with an active compression decompression device, the adherence sufficient to transfer decompression force between the active compression decompression device and the patient's chest during the CPR treatment.

A system for performing an active compression decompression (ACD) treatment on a patient includes a platform for placement under a patient, a chest compression actuator that may include a belt configured to extend over a thorax of the patient, an upward force actuator, a coupling mechanism for coupling the upward force actuator to the thorax of the patient to transfer a decompressing force from the upward force actuator to the thorax of the patient, and a motor that is coupled to the belt, the motor configured to cause the belt to tighten about the thorax of the patient and exert a compressing force on the thorax of the patient; and cause the belt to loosen about the thorax of the patient and allow the upward force actuator to cause decompression of the patient.

A system for assisting with a cardiopulmonary resuscitation (CPR) treatment being administered to a patient. In one aspect, the system includes electrodes to provide an ECG signal of the patient, one or more sensors configured to measure an intrinsic myocardial wall movement of the patient, and one or more processors. The one or more processors are configured to perform operations including: during the CPR treatment being administered to the patient, receiving an input from the sensor(s), processing the input from the sensor(s) and the ECG signal, determining, based on processing, whether the intrinsic myocardial wall movement is indicative of a perfusion movement of the patient's heart, and providing an indication to a user of the system based on the determination.

Systems and methods related to the field of cardiac resuscitation, and in particular to devices for assisting rescuers in performing cardio-pulmonary resuscitation (CPR) are described herein. The system includes a chest compression device having force sensing capabilities, for providing feedback in enhancing the quality of acute care. The force sensor(s) may exhibit varying resolutions over different dynamic force ranges, for example, to provide information helpful to the resuscitative treatment. Chest compression devices that are able to sense force may be able to assist a system in providing accurate chest compression depth and rate information, as well as assess the amount of work exerted by one or more rescuers during the course of resuscitation. Force sensors described herein may employ relatively inexpensive components, such as pressure sensors, emitters, optical detectors, simple circuit boards, springs, compliant/resilient materials, electrically resistive layers, force-sensitive materials, amongst other suitable parts.