Near-infrared spectroscopy in post-cardiac arrest patients undergoing therapeutic hypothermia
Suffoletto B et al. – The authors found that peripheral skin temperature in post–arrest critically ill patients undergoing TH strongly influences tissue oxygen desaturation and reoxygenation rates. In additional, changes in NIRS derived variables were independent of measures of shock, vasopressor use or illness severity.Methods
- This prospective, observational study included a convenience sample of 30 patients hospitalized in a multidisciplinary intensive care unit in a university hospital and treated with therapeutic hypothermia.
- Near infrared spectroscopy (NIRS) was used to measure thenar tissue oxygen saturation, desaturation rate and saturation recovery rate after the vascular occlusion test, conducted within 24hours of hospital admission and within 12hours of initiating re-warming.
- Measurements included heart rate (HR), mean arterial blood pressure (MAP), oxygen saturation, use of vasopressors and sedatives, core body (esophageal) and peripheral skin temperature and sequential organ failure assessment (SOFA) score.
- Peripheral skin temperature was found to have a significant effect on StO2 deoxygenation and recovery slopes, resulting in lower rates at colder temperatures.
- This effect was independent of MAP, HR, and core temperature.
- NIRS-derived variables were not associated with SOFA score or use of vasopressors and did not predict mortality.