RESUMEN
Background: In neurologic prognostication of comatose survivors from cardiac arrest, two independent predictors of poor outcome are the loss of the Pupillary light reflex (PLR) and the loss of the N20 response from Somatosensory Evoked potentials (SSEP). The PLR can be quantitatively assessed by pupillometry. Both tests depend on the midbrain, in which a dysfunction reflects a severe hypoxic injury. We reasoned that a certain level of defective PLR would be predictive of a bilaterally absent SSEP N20 response. Method: Neurological Pupil index (NPi) from the pupillometry and the SSEP N20 response were registered >48 h after cardiac arrest in comatose survivors. Clinical data were retrospectively analyzed. A receiver operating characteristic curve was used to evaluate the capacity of NPi to predict bilaterally absent SSEP N20 response. An NPi threshold value resulting in <5% false positive rate (FPR) for bilaterally absent N20 response was identified. Results: From February 2020 to August 2022, we included 54 patients out of which 49 had conclusive pupillometry and SSEP examinations. The NPi threshold value with FPR < 5% was 3.4, yielding 36% sensitivity (95% CI 18-55) and significantly discriminated between respective groups with preserved and bilaterally absent N20 response to SSEP (p-value <0.01). Conclusion: In this limited cohort, NPi < 3.4 in patients remaining comatose >48 hours after cardiac arrest predicted bilateral loss of the SSEP N20 response with a FPR < 5%. If validated in a larger cohort, an NPi threshold may be clinically applied in settings where SSEP is unavailable.
RESUMEN
BACKGROUND: Post-resuscitation care of comatose survivors from cardiac arrest includes target temperature management (TTM) to mitigate cerebral reperfusion injury. High-quality TTM requires protocols enhancing good precision. This study explored how the quality of TTM may have evolved with increasing experience from clinical trial protocols and standard operating procedures. We hypothesized that there would be a positive effect over time, detectable between trial periods and between trial periods and later everyday practice. METHODS: Three TTM quality parameters were defined: time to target, temperature variability, and fever incidence. Data from 181 patients treated during three different time periods in a tertiary center were analyzed; 45 from Period 1 (local trial cohort 2011-2013) targeting 33°C or 36°C; 76 from Period 2 (local trial cohort 2018-2020) targeting 33 or <37.5°C; 60 from Period 3 (current standard operating procedure 2020-2021) targeting 36°C. Groups of similar target temperatures from different time periods were compared using ordinary group statistics. RESULTS: TTM quality in all three parameters increased between trial periods. There were no differences in TTM quality as to temperature variability or fever incidence between the <37.5°C Period 2 and the 36°C Period 3 groups. A 33°C target temperature was associated with lower fever incidence than 36°C and <37.5°C target regimes. CONCLUSION: The observed increase in TTM quality in this single-center study may be a result of increased competence through learning and training in different strict TTM protocols. If so, the results of this study further support the protocolization of post-cardiac arrest intensive care.
