Measuring forces and frequency during active compression decompression cardiopulmonary resuscitation: a device for training, research and real CPR

Active compression decompression (ACD) cardiopulmonary resuscitation (CPR) is possibly a superior alternative to standard (STD) CPR, but an optimal co mpression and decompression pattern has to be ensured. ACD-CPR can be evalu ated during CPR training sessions using commercially available manikins; ho wever devices for recording compression and decompression forces or frequen cy during real CPR are lacking, Using the Ambu CardioPump(R) without changi ng its mechanical characteristics, two force transducers were integrated in to the ACD device. Using specially designed electronics and a portable comp uter, compression and decompression forces were measured and displayed cont inuously and compression frequency and the compression decompression phase are calculated on-line during real CPR action. All measured parameters were stored on a hard disk for later retrieval and analysis. Linearity of force measurement was better than 6% within a -250- + 500 N range. The error in repeatability was below 5% thus outperforming the original mechanical force measurement system of the Ambu CardioPump(R). Compression frequency was ca lculated very accurately (error < 1%). The system has been successfully use d during CPR training, during ACD-CPR in 37 corpses under research conditio ns and in five out-of-hospital CPR casualties. Simple and safe in use, our modified CardioPump(R) with integrated electronics provides an important, t echnically advanced solution for monitoring ACD-CPR on-line. It warrants qu ality assurance during ACD-CPR training and in real CPR scenarios and guara ntees accurate recording of compression and decompression forces and compre ssion frequency. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved .