Use of online blood volume and blood temperature monitoring during haemodialysis in critically ill patients with acute kidney injury: a single-centre randomized controlled trial.

BACKGROUND: Little is known about the clinical impact on cardiovascular stability during intermittent haemodialysis (IHD) for acute kidney injury (AKI) of online monitoring devices that control blood volume (BV) and blood temperature in the intensive care unit (ICU) setting. We compared different dialysis treatment modalities with or without these new systems among critically ill patients requiring IHD. METHODS: In a prospective single-centre three-arm randomized controlled trial, 600 dialysis sessions in 74 consecutive AKI critically ill patients were involved to assess intradialytic hypotension. Standard dialysis therapy with constant ultrafiltration (UF) rate, cool dialysate and high sodium conductivity (Treatment A) was compared to regimens with adjunctive interventions including BV control (Treatment B) and the combination of BV and active blood temperature control (Treatment C). Each dialysis session was randomly assigned to one of the three treatment arms and served as statistical unit. RESULTS: Five hundred and seventy-two dialysis sessions were analysed (188, 190 and 194 in Treatments A, B and C, respectively). Hypotension occurred in 16.6% treatments, with similar rates among the arms. Haemodynamic parameters and dialysis-related complications did not differ between therapies. Based on generalized estimating equation adjusted to dialysate sodium conductivity, higher Sequential Organ Failure Assessment the day of dialysis session, the need for vasopressors and lower systolic blood pressure at the onset of the session were identified as independent predictors of hypotensive episodes, whereas regimens containing the new online monitors were not. CONCLUSIONS: These results suggest that both actively controlled body temperature and UF profiled by online monitoring systems have no significant impact on the incidence of intradialytic hypotension in the ICU setting. Further research is needed before the use of these new sophisticated automatic methods can be applied routinely to the ICU setting.

Serum neuron-specific enolase as predictor of outcome in comatose cardiac-arrest survivors: a prospective cohort study.

BACKGROUND: The prediction of neurological outcome in comatose patients after cardiac arrest has major ethical and socioeconomic implications. The purpose of this study was to assess the capability of serum neuron-specific enolase (NSE), a biomarker of hypoxic brain damage, to predict death or vegetative state in comatose cardiac-arrest survivors. METHODS: We conducted a prospective observational cohort study in one university hospital and one general hospital Intensive Care Unit (ICU). All consecutive patients who suffered cardiac arrest and were subsequently admitted from June 2007 to February 2009 were considered for inclusion in the study. Patients who died or awoke within the first 48 hours of admission were excluded from the analysis. Patients were followed for 3 months or until death after cardiopulmonary resuscitation. The Cerebral Performance Categories scale (CPC) was used as the outcome measure; a CPC of 4-5 was regarded as a poor outcome, and a CPC of 1-3 a good outcome. Measurement of serum NSE was performed at 24 h and at 72 h after the time of cardiac arrest using an enzyme immunoassay. Clinicians were blinded to NSE results. RESULTS: Ninety-seven patients were included. All patients were actively supported during the first days following cardiac arrest. Sixty-five patients (67%) underwent cooling after resuscitation. At 3 months 72 (74%) patients had a poor outcome (CPC 4-5) and 25 (26%) a good outcome (CPC 1-3). The median and Interquartile Range [IQR] levels of NSE at 24 h and at 72 h were significantly higher in patients with poor outcomes: NSE at 24 h: 59.4 ng/mL [37-106] versus 28.8 ng/mL [18-41] (p < 0.0001); and NSE at 72 h: 129.5 ng/mL [40-247] versus 15.7 ng/mL [12-19] (p < 0.0001). The Receiver Operator Characteristics (ROC) curve for poor outcome for the highest observed NSE value for each patient determined a cut-off value for NSE of 97 ng/mL to predict a poor neurological outcome with a specificity of 100% [95% CI = 87-100] and a sensitivity of 49% [95% CI = 37-60]. However, an approach based on a combination of SSEPs, NSE and clinical-EEG tests allowed to increase the number of patients (63/72 (88%)) identified as having a poor outcome and for whom intensive treatment could be regarded as futile. CONCLUSION: NSE levels measured early in the course of patient care for those who remained comatose after cardiac arrest were significantly higher in patients with outcomes of death or vegetative state. In addition, we provide a cut-off value for NSE (> 97 ng/mL) with 100% positive predictive value of poor outcome. Nevertheless, for decisions concerning the continuation of treatment in this setting, we emphasize that an approach based on a combination of SSEPs, NSE and clinical EEG would be more accurate for identifying patients with a poor neurological outcome.

Predictors of mortality and short-term physical and cognitive dependence in critically ill persons 75 years and older: a prospective cohort study.

BACKGROUND: The purpose of this study was to identify predictors of 3-month mortality in critically ill older persons under medical care and to assess the clinical impact of an ICU stay on physical and cognitive dependence and subjective health status in survivors. METHODS: We conducted a prospective observational cohort study including all older persons 75 years and older consecutively admitted into ICU during a one-year period, except those admitted after cardiac arrest, All patients were followed for 3 months or until death. Comorbidities were assessed using the Charlson index and physical dependence was evaluated using the Katz index of Activity of Daily Living (ADL). Cognitive dependence was determined by a score based on the individual components of the Lawton index of Daily Living and subjective health status was evaluated using the Nottingham Health Profile (NHP) score. RESULTS: One hundred patients were included in the analysis. The mean age was 79.3 ± 3.4 years. The median Charlson index was 6 [IQR, 4 to 7] and the mean ADL and cognitive scores were 5.4 ± 1.1 and 1.2 ± 1.4, respectively, corresponding to a population with a high level of comorbidities but low physical and cognitive dependence. Mortality was 61/100 (61%) at 3 months. In multivariate analysis only comorbidities assessed by the Charlson index [Adjusted Odds Ratio, 1.6; 95% CI, 1.2-2.2; p < 0.003] and the number of organ failures assessed by the SOFA score [Adjusted Odds Ratio, 2.5; 95% CI, 1.1-5.2; p < 0.02] were independently associated with 3-month mortality. All 22 patients needing renal support after Day 3 died. Compared with pre-admission, physical (p = 0.04), and cognitive (p = 0.62) dependence in survivors had changed very little at 3 months. In addition, the mean NHP score was 213.1 ± 132.8 at 3 months, suggesting an acceptable perception of their quality of life. CONCLUSIONS: In a selected population of non surgical patients 75 years and older, admission into the ICU is associated with a 3-month survival rate of 38% with little impact on physical and cognitive dependence and subjective health status. Nevertheless, a high comorbidity level (ie, Charlson index), multi-organ failure, and the need for extra-renal support at the early phase of intensive care could be considered as predictors of death.