RESUMEN
Background: Bioimpedance spectroscopy (BIS) is a non-invasive method used to measure fluid volumes. In this report, we compare BIS measurements from patients with heart failure (HF) to those from healthy adults, and describe how these point-of-care fluid volume assessments may be applied to HF management. Methods and results: Fluid volumes were measured in 64 patients with NYHA class II or III HF and 69 healthy control subjects. BIS parameters including extracellular fluid (ECF), intracellular fluid (ICF), total body water (TBW), and ECF as a percentage of TBW (ECF%TBW) were analyzed. ECF%TBW values for the HF and control populations differed significantly (49.2 ± 3.2% vs. 45.2 ± 2.1%, respectively; p < 0.001); both distributions satisfied criteria for normality. Interquartile ranges did not overlap (46.7-51.0% vs. 43.8-46.4%, respectively; p < 0.001). Subgroup analyses of HF patients who underwent transthoracic echocardiography showed that impedance measurements correlated with inferior vena cava size (Pearson correlation -0.73, p < 0.0001). A case study is presented for illustrative purposes. Conclusions: BIS-measured ECF%TBW values were significantly higher in HF patients as compared to adults without HF. We describe three strata of ECF%TBW (normal, elevated, fluid overload) that may aid in clinical risk stratification and fluid volume monitoring of HF patients. Clinical Trial Registration: COMPARE - www.ClinicalTrials.gov; IMPEL - www.ClinicalTrials.gov; Heart Failure at Home - www.ClinicalTrials.gov, identifier: NCT02939053; NCT02857231; NCT04013373.
RESUMEN
We sought to evaluate the safety and feasibility of mild therapeutic hypothermia using an endovascular temperature management system in awake acute ischemic stroke patients. The Intravascular Cooling in the Treatment of Stroke (ICTuS) study was an uncontrolled, multicenter development and feasibility study of conscious patients (n = 18) presenting within 12 hours of onset of an acute ischemic stroke at 5 clinical sites in the United States. Enrolled patients were to undergo core temperature management using an endovascular cooling system to induce and maintain mild, therapeutic hypothermia (target temperature of 33.0 degrees C) for a period of either 12 or 24 hours, followed by controlled rewarming to 36.5 degrees C over the subsequent 12-hour period. Nine patients underwent 12 hours of cooling followed by 12 hours of controlled rewarming, and 6 patients underwent 24 hours of cooling followed by 12 hours of controlled rewarming. Three patients underwent <1.5 hours of hypothermia due to clinical or technical issues. We also developed an antishivering regimen using buspirone and meperidine administered prophylactically to suppress shivering. The endovascular cooling catheter was well tolerated, with acceptable adverse event rates. Increasing the duration of hypothermia administration from 12 hours to 24 hours did not appear to increase the incidence or severity of adverse effects. Endovascular cooling with a proactive antishivering regimen can be accomplished in awake stroke patients. Further studies are needed to establish the safety and efficacy of this approach.