Mathers J et al, 2015: Cardiac Dysrhythmias in Children Undergoing Extracorporeal Shock Wave Lithotripsy Under General Anesthesia or Propofol Sedation: A Prospective, Observational Cohort Study.
Mathers J, Troncoso Solar B, Harding L, Smeulders N, Hume-Smith H.
Department of Anaesthesia, Great Ormond Street Hospital, London, United Kingdom.
Department of Urology, Great Ormond Street Hospital, London, United Kingdom.
Department of Anaesthesia, Great Ormond Street Hospital, London, United Kingdom.
Abstract
OBJECTIVE: To assess the frequency and severity of cardiac dysrhythmias and identify any intraoperative or postoperative complications in children undergoing extracorporeal shock wave lithotripsy (ESWL).
METHODS: All children coming to our institution for ESWL from June 2014 to January 2015 were prospectively enrolled in an observational cohort study. Intraoperative cardiac dysrhythmias and perioperative and postoperative complications were recorded.
RESULTS: In total, 21 children aged 1-18 years were enrolled receiving a total of 26 treatments. Intravenous sedation was used in 19 cases and general anesthesia with an inhalational agent in 7 cases. Cardiac dysrhythmias occurred in 58% of children. No hemodynamic instability was noted. No therapies were terminated because of dysrhythmias, and there were no postoperative cardiac dysrhythmias.
CONCLUSION: ESWL remains a safe therapy for children with urinary stone disease. Although we experienced more dysrhythmias than currently published literature, there were no long-term adverse outcomes and children were able to go home the same day.
Urology. 2015 Jul 22. pii: S0090-4295(15)00697-4. doi: 10.1016/j.urology.2015.07.017. [Epub ahead of print]
Comments 1
In this article the authors have recorded the occurrence of dysrhythmias in children exposed to SWL. They surprisingly noted dysrhythmias in as many as 58% of their children. That high percentage of abnormal cardiac electrical activity is different from my own experience with (Storz SLX-lithotripters). Although all these episodes terminated by themselves without consequences, there seems to be place for a note of caution. The reason for not using ECG-triggered SWL, because it would slow down the frequency of SW administration, is a weak argument. Shockwaves delivered at frequencies corresponding to the heart rate (60-90/minute) would in fact favour stone disintegration. The mean frequencies reported in the article were between 67 and 77 per minute. Most studies have shown a better outcome of SWL with low rather than high frequencies. It had indeed been of great interest in this regard to compare treatments with and without ECG triggering.
Why shockwaves induce dysrhythmias is not fully understood. It might of course be related to the shape of the shockwave, but my personal view is that the electromagnetic field, rather than the shockwave geometry itself, is responsible for the abnormal electrical activities.