External authors:

• Erick Strange ( Pontificia Universidad Catolica de Chile )
• Fernando R. Altermatt ( Pontificia Universidad Catolica de Chile )
• Luis Caceres ( Pontificia Universidad Catolica de Chile )
• Christopher Morrison ( Pontificia Universidad Catolica de Chile )
• Luis Cortes ( Red Salud UC CHRISTUS )
• Nicolas I. Sumonte ( Pontificia Universidad Catolica de Chile , Natl Ctr Artificial Intelligence )

Abstract:

Background Patients with continuous nerve blocks need structured follow-up, but daily phone calls are resource-intensive. Automated text messaging may offer a scalable alternative.Methods In this randomized feasibility trial, 100 outpatients with continuous peripheral nerve catheters were assigned to either automated WhatsApp-based follow-up (mobile app group) or daily telephone calls (phone group) for 3 days. The primary outcome was usability, measured by the System Usability Scale (SUS, 0-100 scale; scores >= 68 indicate acceptable usability, >= 85 excellent usability). Secondary outcomes included satisfaction, response rates, reconsultations, and catheter-related events.Results Out of 100 randomized patients, 91 were analyzed (46 mobile app group; 45 phone call group). The mobile app achieved a mean SUS score of 87.8, reflecting excellent usability. Satisfaction and response rates were high and similar between groups. Reconsultations were more frequent with the app (28.3% vs 6.7%), mainly non-urgent patient calls. Reports of minor catheter-related events were also more common in the app group (60.9% vs 37.8%).Conclusions Automated messaging is feasible, demonstrates excellent usability, and preserves patient satisfaction. The higher rates of minor symptom reporting and reconsultations highlight areas for refinement in future research.Trial registration number NCT06313294.