Positioning device for use in apparatus for treating sudden cardiac arrest

#The present application is a 35 U.S.C. §§371 national phase conversion of PCT/SE2004/001596, filed Nov. 4, 2004, which claims priority of Swedish Patent Application No. 0303054-1, filed Nov. 17, 2003. The PCT International Application was published in the English language.

#The present invention relates to a positioning device for use in apparatus for treating sudden cardiac arrest.

#Sudden cardiac arrest is commonly treated mechanically and/or by electrical defibrillation. Mechanical treatment may be given manually or by a chest compression apparatus. The length of a compression/decompression cycle is typically from half a second to one second. A number of chest compression apparatus are known in the art, such as the pneumatically driven LUCAS™ mechanical chest compression/decompression system (“Lucas™ system”; an apparatus for compression and physiological decompression in Cardio-Pulmonary Resuscitation, CPR, manufactured by Jolife A B, Lund, Sweden). Specifically the Lucas™ system comprises a support structure and a compression/decompression unit. The support structure includes a back plate for positioning the patient's back posterior to the patient's heart and a front part for positioning around the patient's chest anterior to the heart. The front part has two legs, each having a first end pivotally connected to at least one hinge of the front part and a second end removably attachable to the back plate. The front part is devised to centrally receive the compression/decompression unit which is arranged to repeatedly compress/decompress the patient's chest when the front part is attached to the back plate. The compression/decompression unit comprises a pneumatic unit arranged to drive and control compression and decompression, an adjustable suspension unit to which a compression/decompression pad is attached, and a means for controlling the position of the pad in respect of the patient's chest. Defibrillation may be provided independently of and concomitantly with mechanical stimulation.

#In the attached drawing,

#FIG. 1 is a perspective view of first embodiment of the device of the invention mounted at the legs of an apparatus for treating sudden cardiac arrest fully enclosing a patient to which mechanical heart compression/decompression is being provided, in a perspective view;

#FIG. 2 is a second embodiment of the invention mounted at left and right legs of an apparatus of the aforementioned kind but with the patient omitted, the flexible means of the device disposed in a horizontal plane being shown in a top view but mounting being shown in a sectional view;

#FIG. 1 shows a patient in a supine position receiving heart massage by an apparatus for treating cardiac arrest. The apparatus for treating cardiac arrest is only shown to the extent required for illustrating the principles of the present invention. The apparatus, which shares the general design of the Lucas™ system, encloses the patient in the sternum region. The uppermost portion of the enclosure is positioned at a substantial distance above the patient's chest. “Left” and “right” designate positions from the patient's perspective. Curved left 1 and right 2 legs extend from a bottom plate (not shown) at which their first ends are releasably mounted. At their second ends the legs 1, 2 are swivelingly mounted via joints 7, 8, respectively, at a bridge element 3 that carries a central pneumatic compression/decompression unit 4. A plunger extends downwards from the compression/decompression unit 4 and terminates in a suction cup 6. By a reciprocating movement B of the plunger and the suction cup 6 the patient's breast is compressed and decompressed periodically. In its top or apical position the cup 6 abuts the uncompressed breast at the sternum, from which position the compression/decompression cycle starts. The apparatus for treating cardiac arrest allows the depth and rate of compression to be adjusted to suit the individual patient. Due to the anatomy of the chest the apparatus has a tendency to move in a caudal direction A. This movement is restricted by the positioning device of the invention which comprises a flexible but essentially non-elastic strap 10 having two end portions flanking a central strap portion which passes through a neck support 15. The strap is fixed via snap connections 32, 33 at mountings 30, 31 which, in turn are fixed to the left 1 and right legs 2, respectively. The snap connections 32, 33 comprise tensioning means and are shown in greater detail in FIG. 8. A belt 30 of synthetic textile material encloses tightly the right leg 2. At its short side it is connected by stitched seams 39 to the ends of a short piece 37 of same material so as to form an eye which holds a bar 40 of the male member 38 of a snap connection 32 of ordinary make. Its female member 41 comprises buckle means in form of three bars 42, 43, 44 defining two slots in which the flexible strap 10 is mounted and then is folded back. The strap can be tensioned by pulling the back-folded free end portion 34.

#The device of the invention thus consists of a flexible strap provided with tensioning and, possibly, other means such as neck support means, two mountings releasably or non-releasably fixed to the legs of an apparatus for treating cardiac arrest, and releasable means for connecting left and right free end portions of the strap with the left and right mountings, respectively.

#FIGS. 2 to 7 illustrate further preferred embodiments of the invention. The person skilled in the art will realize that the connecting, mounting, and tensioning means of the various embodiments are substantially exchangeable.