CPR mask with compression timing metronome and methods

#This invention relates generally to the field of resuscitation, and in particular, to the field of cardiopulmonary resuscitation. More specifically, the invention is related to techniques for assisting a rescuer in performing appropriately timed chest compressions and in ventilating a patient.

#Sudden cardiac arrest is a significant cause of death throughout the world. The performance of cardiopulmonary resuscitation (CPR) is one well-accepted technique to assist in restoring cardiac function. The effectiveness of CPR may depend upon the manner of its performance. For example, when performing CPR it may be desirable to compress the chest at a certain rate. Also, it may be desirable to perform chest compressions according to a certain rhythm as described generally in “The Guidelines of for CPR and Emergency Cardiovascular Care” , JAMA, 1992; 268: 2172-2295, the complete disclosure of which is herein incorporated by reference. Even when properly trained, however, the correct performance of CPR on a patient can be difficult. For example, it may be difficult to evaluate whether chest compressions are being performed at an optimal rate.

#When performing CPR, it may also be desirable to periodically ventilate the patient, e.g., using mouth to mouth resuscitation. However, the proper timing of ventilations may be difficult to evaluate when performing CPR. Further, many ventilation techniques may transfer respiratory pathogens between the rescuer and the patient.

#FIG. 1 is a top view of one embodiment of a facial mask having a metronome according to the invention.

#FIG. 2 is a side view of the facial mask of FIG. 1.

#FIG. 3 is a partial cutaway side view of the mask of FIG. 2 when respiratory gases are being supplied to the patient.

#In one embodiment, the invention provides a facial mask that incorporates a metronome to assist a rescuer in the performance of CPR. The facial mask is configured to be secured to a patient's face to facilitate ventilation of the patient while performing CPR. The mask may be secured manually by the rescuer, by use of an adhesive, or by the use of straps placed around the patient's head. By incorporating a metronome, a chest compression signal may be produced to guide the rescuer in performing regular and appropriately timed chest compressions. For example, the metronome may produce a repeating chest compression signal that repeats at a constant rate in the range from about 50 signals per minute to about 100 signals per minute, and more preferably at about 80 signals per minute. The metronome may also be configured to produce a regular and repeating ventilation signal to indicate when the patient should be ventilated. For example, the ventilation signal may be produced one to two times about every 5 to 25 chest compression signals to indicate that a ventilation should be performed.

#A variety of signals may be employed to indicate when chest compressions or ventilations should be performed. Such signals may include, for example, visual signals, audible signals, and the like. Merely by way of example, such signals may include a flashing light, a beep, a voice, a whistle, a bell, vibrations, and the like. Different types of the same signal or different signals may be used to differentiate between a chest compression signal and a ventilation signal. For example, the signals may be differentiated based on colors, sound levels, frequency, pitch, voice commands, and the like, as well as the use of different types of signals. Merely by way of example, an audible beep may be produced each time a chest compression is to be performed while an audible “breathe” would be produced to indicate that a ventilation should be performed. Hence, such a cadence would be as follows: “beep, beep, beep, beep, breathe, beep . . . ” Further, it will be appreciated that different types of signals may be produced at the same time to enhance their perception. For example, a flashing light and a beep may be produced at the same time to indicate that a chest compression should occur.

#The facial masks may also utilize a valve system to permit the exchange of respiratory gases. The facial masks and/or valve systems may have a variety of designs, and may be constructed of a variety of materials, including rubber, silicone, plastic, polyurethane, polycarbonate, acrylic, blends, other synthetic poly carbons, and the like. In one aspect, the valve system may be configured to prevent respiratory gases or fluids produced by the patient from coming into contact with the rescuer. For example, the valve system may include an inhalation port that is only opened during ventilation so that gases from the patient are not able to exit through the inhalation port. Further, the valve system may include an exhalation port that is apart from the inhalation port to permit the exit of respiratory gases from the patient only through the exit port. Preferably, the exit of respiratory gases from the patient will be permitted only after a ventilation has stopped.