Optimizing Transnasal Temperature Modulation: Efficacy and Safety of a Single-Nostril Cooling Device in Critically Ill Patients.

Effective temperature management in critically ill patients with cerebrovascular injuries is vital. A transnasal temperature modulation device (tnTMD) has shown promise in achieving normothermia, but challenges with its dual-nostril configuration limited its efficacy. This study evaluates the efficacy and safety of a single-nostril configuration and identifies the optimal flow rate for effective cooling. This was a prospective, multi-center, open-label study of temperature reduction to achieve normothermia utilizing a tnTMD. Thirty adult patients with ischemic or hemorrhagic stroke, seizure, or metabolic encephalopathy underwent cooling with the tnTMD. Ten patients were treated with the dual-nostril configuration for 8 hours at 60 L/min, and another 10 patients for 24 hours at the same flow rate. Ten patients were treated with the single-nostril configuration for 24 hours at incrementally escalating flow rates (30, 40, and 50 L/min). Core temperature, shivering, and adverse events were reported. The statistical analysis compared reductions in temperature and safety outcomes across flow rates in the single-nostril cohort. The analysis also compares efficacy data from the dual-nostril treatment with those from single-nostril treatments of the tnTMD. A total of 10 patients underwent single-nostril cooling. The 40 L/min flow rate achieved the most consistent normothermia within 4 hours, with reduced temperature burden over 24 hours compared with 30 L/min (p = 0.03). Cooling efficacy at 40 and 50 L/min was similar, but 40 L/min showed lower variance. Shivering occurred in three cases; however, no severe cases of shivering were observed. There were no severe adverse effects. The single-nostril device demonstrated efficacy comparable to that of the dual-nostril approach, with improved practicality. The tnTMD effectively achieved normothermia with a novel single-nostril design with an optimal flow rate of 40 L/min. Given its ease of use and benign safety profile, future research should explore its applicability in non-intubated patients and in longer-duration cooling intervention.