Characterization of end-of-life electroencephalographic surges in critically ill patients.

Neuromonitoring devices to assess level of sedation are now used commonly in many hospital settings. The authors previously reported that electroencephalicgraphic (EEG) spikes frequently occurred after the time of death in patients being neuromonitored at the time of cessation of circulation. In addition to the initial report, end-of-life electrical surges (ELES) have been subsequently documented in animal and human studies by other investigators. The frequency, character, intensity, and significance of ELES are unknown. Some have proposed that patients should not be declared dead for purposes of organ donation prior to the occurrence of an ELES. If clinical practice were altered to await the presence of an ELES, there could be detrimental consequences to donated organs and their recipients. To better characterize ELES, the authors retrospectively assessed the frequency and nature of ELES in serial patients. To better document ELES, they collected neuromonitoring, demographic, and clinical data on consecutive patients who expired while being actively monitored as part of their standard palliative care. These data were retrospectively collected when available as a convenience sample. The authors assessed 35 patients of which 7 were clinically confirmed as brain dead. None of the brain-dead patients displayed an ELES. Thirteen of the 28 remaining patients (46.4%) exhibited an ELES. The ELES observed were demonstrated to have high frequency EEG signal. The mean peak amplitude of ELES as measured by Patient State IndexTM (PSI) was 58.5 ± 25.7. In this preliminary assessment, the authors found that ELES are common in critically ill patients who succumb. The exact cause and significance of ELES remain unknown; further study is warranted.

Furosemide Stress Test and Biomarkers for the Prediction of AKI Severity.

Clinicians have access to limited tools that predict which patients with early AKI will progress to more severe stages. In early AKI, urine output after a furosemide stress test (FST), which involves intravenous administration of furosemide (1.0 or 1.5 mg/kg), can predict the development of stage 3 AKI. We measured several AKI biomarkers in our previously published cohort of 77 patients with early AKI who received an FST and evaluated the ability of FST urine output and biomarkers to predict the development of stage 3 AKI (n=25 [32.5%]), receipt of RRT (n=11 [14.2%]), or inpatient mortality (n=16 [20.7%]). With an area under the curve (AUC)±SEM of 0.87±0.09 (P<0.0001), 2-hour urine output after FST was significantly better than each urinary biomarker tested in predicting progression to stage 3 (P<0.05). FST urine output was the only biomarker to significantly predict RRT (0.86±0.08; P=0.001). Regardless of the end point, combining FST urine output with individual biomarkers using logistic regression did not significantly improve risk stratification (ΔAUC, P>0.10 for all). When FST urine output was assessed in patients with increased biomarker levels, the AUC for progression to stage 3 improved to 0.90±0.06 and the AUC for receipt of RRT improved to 0.91±0.08. Overall, in the setting of early AKI, FST urine output outperformed biochemical biomarkers for prediction of progressive AKI, need for RRT, and inpatient mortality. Using a FST in patients with increased biomarker levels improves risk stratification, although further research is needed.

Intravenous angiotensin II for the treatment of high-output shock (ATHOS trial): a pilot study.

INTRODUCTION: Patients with distributive shock who require high dose vasopressors have a high mortality. Angiotensin II (ATII) may prove useful in patients who remain hypotensive despite catecholamine and vasopressin therapy. The appropriate dose of parenteral angiotensin II for shock is unknown. METHODS: In total, 20 patients with distributive shock and a cardiovascular Sequential Organ Failure Assessment score of 4 were randomized to either ATII infusion (N =10) or placebo (N =10) plus standard of care. ATII was started at a dose of 20 ng/kg/min, and titrated for a goal of maintaining a mean arterial pressure (MAP) of 65 mmHg. The infusion (either ATII or placebo) was continued for 6 hours then titrated off. The primary endpoint was the effect of ATII on the standing dose of norepinephrine required to maintain a MAP of 65 mmHg. RESULTS: ATII resulted in marked reduction in norepinephrine dosing in all patients. The mean hour 1 norepinephrine dose for the placebo cohort was 27.6 ± 29.3 mcg/min versus 7.4 ± 12.4 mcg/min for the ATII cohort (P =0.06). The most common adverse event attributable to ATII was hypertension, which occurred in 20% of patients receiving ATII. 30-day mortality for the ATII cohort and the placebo cohort was similar (50% versus 60%, P =1.00). CONCLUSION: Angiotensin II is an effective rescue vasopressor agent in patients with distributive shock requiring multiple vasopressors. The initial dose range of ATII that appears to be appropriate for patients with distributive shock is 2 to 10 ng/kg/min. TRIAL REGISTRATION: Clinicaltrials.gov NCT01393782. Registered 12 July 2011.

Safety and dose-finding study of activated protein C (drotrecogin alfa activated) as an anticoagulant in end-stage renal disease patients treated with hemodialysis.

BACKGROUND/AIMS: End-stage renal disease (ESRD) patients treated with hemodialysis (HD) experience a high risk of death. ESRD patients with elevated levels of pro-inflammatory cytokines are at increased risk of death from cardiovascular events and infection. HD is often facilitated by the use of an anticoagulant. We hypothesized that the use of an anticoagulant that also possessed anti-inflammatory qualities without significant immunosuppressive effects may reduce the risk of death. In this pilot study, we sought to determine the optimal dose of activated protein C (APC) to achieve adequate regional anticoagulation for HD and determine if the drug can be safely used in ESRD patients treated with HD. METHODS: Twelve stable HD patients were enrolled into this safety and dose-finding study. Varying doses of APC were administered in place of usual heparin at varying doses to determine the range of APC that can be used for extracorporeal circuit anticoagulation. Partial thromboplastin time was assessed at fixed intervals during the HD treatment. RESULTS: The average age of study patients was 49 ± 12 years. 75% of patients were African-American and 66.7% were male. The optimal dose of APC to induce adequate anticoagulation was 24-30 µg/kg/h. No patients experienced any serious adverse events. One patient had their infusion stopped early due to refractory intradialytic hypertension. CONCLUSIONS: For ESRD patients undergoing HD, an initial starting dose of 24-30 µg/kg/h achieves a target partial thromboplastin time that should be adequate for circuit anticoagulation. This dose appears safe and was well tolerated.

Development and standardization of a furosemide stress test to predict the severity of acute kidney injury.

INTRODUCTION: In the setting of early acute kidney injury (AKI), no test has been shown to definitively predict the progression to more severe stages. METHODS: We investigated the ability of a furosemide stress test (FST) (one-time dose of 1.0 or 1.5 mg/kg depending on prior furosemide-exposure) to predict the development of AKIN Stage-III in 2 cohorts of critically ill subjects with early AKI. Cohort 1 was a retrospective cohort who received a FST in the setting of AKI in critically ill patients as part of Southern AKI Network. Cohort 2 was a prospective multicenter group of critically ill patients who received their FST in the setting of early AKI. RESULTS: We studied 77 subjects; 23 from cohort 1 and 54 from cohort 2; 25 (32.4%) met the primary endpoint of progression to AKIN-III. Subjects with progressive AKI had significantly lower urine output following FST in each of the first 6 hours (p<0.001). The area under the receiver operator characteristic curves for the total urine output over the first 2 hours following FST to predict progression to AKIN-III was 0.87 (p = 0.001). The ideal-cutoff for predicting AKI progression during the first 2 hours following FST was a urine volume of less than 200mls(100ml/hr) with a sensitivity of 87.1% and specificity 84.1%. CONCLUSIONS: The FST in subjects with early AKI serves as a novel assessment of tubular function with robust predictive capacity to identify those patients with severe and progressive AKI. Future studies to validate these findings are warranted.