Mechanisms of pain associated with internal defibrillation shocks: results of a randomized study of shock waveform. Export

@article{Boriani2005Mechanisms, abstract = {BACKGROUND: Shock pain has limited the acceptance of the implantable atrial cardioverter and is a complication of ventricular implantable cardioverter-defibrillator therapy. Rounding off of the peak of a shock waveform reduces pain. Whether the pain reduction results from reduction in the peak voltage or from the rounding has not been established. In other words, does reducing the extreme dV/dt (voltage derivative) of the conventional truncated exponential capacitive discharge waveform reduce pain? OBJECTIVES: The purpose of this study was to compare the relative contributions of peak voltage and waveform shape to pain. METHODS: We compared rounded and conventional waveforms with equal peak voltages. Eighty-five shocks of 50 to 500 V were delivered to 10 patients requiring atrial cardioversion for persistent atrial fibrillation. The patient touched an analog pain scale (0-15 cm) and orally reported a pain score on a scale from 0 to 5. An observer scored thoracic contractions on a scale from 0 to 5. RESULTS: No differences between the rounded and conventional waveform on any scale were noted for either univariate or multivariate analyses. However, all three response scales were strongly predicted by voltage with r(2) = 0.77 (oral), r(2) = 0.86 (analog), and r(2) = 0.85 (contraction) after correcting for patient variability and including a log voltage term. CONCLUSIONS: Patient pain perception was determined primarily by waveform peak voltage and not by the rounding, per se.}, author = {Boriani, G. and Biffi, M. and Silvestri, P. and Martignani, C. and Valzania, C. and Diemberger, I. and Moulder, C. and Mouchawar, G. and Kroll, M. and Branzi, A.}, citeulike-article-id = {4243639}, citeulike-linkout-0 = {http://dx.doi.org/10.1016/j.hrthm.2005.03.024}, citeulike-linkout-1 = {http://view.ncbi.nlm.nih.gov/pubmed/15992726}, citeulike-linkout-2 = {http://www.hubmed.org/display.cgi?uids=15992726}, doi = {10.1016/j.hrthm.2005.03.024}, issn = {1547-5271}, journal = {Heart rhythm : the official journal of the Heart Rhythm Society}, keywords = {rvshocking}, month = {July}, number = {7}, pages = {708--713}, posted-at = {2009-03-31 17:10:00}, priority = {5}, title = {Mechanisms of pain associated with internal defibrillation shocks: results of a randomized study of shock waveform.}, url = {http://dx.doi.org/10.1016/j.hrthm.2005.03.024}, volume = {2}, year = {2005} }

TY - JOUR ID - Boriani2005Mechanisms L3 - citeulike-article-id:4243639 N2 - BACKGROUND: Shock pain has limited the acceptance of the implantable atrial cardioverter and is a complication of ventricular implantable cardioverter-defibrillator therapy. Rounding off of the peak of a shock waveform reduces pain. Whether the pain reduction results from reduction in the peak voltage or from the rounding has not been established. In other words, does reducing the extreme dV/dt (voltage derivative) of the conventional truncated exponential capacitive discharge waveform reduce pain? OBJECTIVES: The purpose of this study was to compare the relative contributions of peak voltage and waveform shape to pain. METHODS: We compared rounded and conventional waveforms with equal peak voltages. Eighty-five shocks of 50 to 500 V were delivered to 10 patients requiring atrial cardioversion for persistent atrial fibrillation. The patient touched an analog pain scale (0-15 cm) and orally reported a pain score on a scale from 0 to 5. An observer scored thoracic contractions on a scale from 0 to 5. RESULTS: No differences between the rounded and conventional waveform on any scale were noted for either univariate or multivariate analyses. However, all three response scales were strongly predicted by voltage with r(2) = 0.77 (oral), r(2) = 0.86 (analog), and r(2) = 0.85 (contraction) after correcting for patient variability and including a log voltage term. CONCLUSIONS: Patient pain perception was determined primarily by waveform peak voltage and not by the rounding, per se. IS - 7 JF - Heart rhythm : the official journal of the Heart Rhythm Society SN - 1547-5271 EP - 713 TI - Mechanisms of pain associated with internal defibrillation shocks: results of a randomized study of shock waveform. VL - 2 SP - 708 KW - rvshocking AU - Boriani, G AU - Biffi, M AU - Silvestri, P AU - Martignani, C AU - Valzania, C AU - Diemberger, I AU - Moulder, C AU - Mouchawar, G AU - Kroll, M AU - Branzi, A PY - 2005/07// UR - http://dx.doi.org/10.1016/j.hrthm.2005.03.024 ER -