A full-thickness burn from pulse oximeter electrical current in an anesthetized child: multidimensional analysis and safety recommendations

Background: This study investigates a case of deep tissue injury in a child caused by prolonged exposure to electrical current from a fingertip pulse oximeter under general anesthesia. Methods: We documented the clinical progression of an 8-year-old girl who sustained a deep burn on her left thumb. A multidimensional evidence chain was constructed by integrating biophysical modeling with device risk analysis. Fascia viability was evaluated by blinded experts using the Baumann scoring criteria. Results: Wound evolution followed a pattern consistent with electrical injury: full-thickness dermal necrosis at day 10, eschar sloughing with viable fascia revealed at day 15 (κ = 0.82, p < 0.01), and complete epithelialization by day 30. Failure analysis identified stress fatigue at the device hinge as a risk point for insulation rupture. Biophysical modeling indicated an electrical current of 0.48 mA and a tissue temperature increase (ΔT) of at least 5.2°C. These findings demonstrate that prolonged exposure to sub-threshold electrical current can induce deep tissue injury via thermal accumulation. Conclusion: This study provides clinical confirmation that prolonged, low-intensity electrical current can cause deep tissue damage through thermal accumulation, a mechanism we term Low-Intensity Long-Duration Electrical (LILDE) injury. We strongly recommend updating international electrical safety standards to include clinical scenario-based testing and establishing an electronic traceability system to enhance medical device safety.