The physiological determinants of near-infrared spectroscopy-derived regional cerebral oxygenation in critically ill adults.

Background: To maintain adequate oxygen delivery to tissue, resuscitation of critically ill patients is guided by assessing surrogate markers of perfusion. As there is no direct indicator of cerebral perfusion used in routine critical care, identifying an accurate strategy to monitor brain perfusion is paramount. Near-infrared spectroscopy (NIRS) is a non-invasive technique to quantify regional cerebral oxygenation (rSO) that has been used for decades during cardiac surgery which has led to targeted algorithms to optimize rSO being developed.

Dysfunctional cerebral autoregulation is associated with delirium in critically ill adults.

Delirium is common during critical illness and is associated with morbidity and mortality, but its pathophysiology is unknown. We tested whether dysfunctional cerebral autoregulation (CA) contributes to the development of delirium. Adult patients ( = 40) with respiratory failure and/or shock were prospectively enrolled.

Low brain tissue oxygenation contributes to the development of delirium in critically ill patients: A prospective observational study.

Purpose: To test the hypothesis that poor brain tissue oxygenation (BtO) during the first 24h of critical illness correlates with the proportion of time spent delirious. We also sought to define the physiological determinants of BtO.

Materials And Methods: Adult patients admitted to the ICU within the previous 24h were considered eligible for enrollment if they required mechanical ventilation, and/or vasopressor support.

Outcomes of elderly critically ill medical and surgical patients: a multicentre cohort study.

Purpose: Very elderly (over 80 yr of age) critically ill patients admitted to medical-surgical intensive care units (ICUs) have a high incidence of mortality, prolonged hospital length of stay, and dependent living conditions should they survive. The primary purpose of this study is to describe the outcomes and differences in outcomes between very elderly medical patients and their surgical counterparts admitted to Canadian ICUs, thereby informing decision-making for clinicians and substitute decision-makers.

Methods: This was a prospective multicentre cohort study of very elderly medical and surgical patients admitted to 22 Canadian academic and non-academic ICUs.

A clinical prediction tool for hospital mortality in critically ill elderly patients.

Background: Very elderly (80 years of age and above) critically ill patients admitted to medical intensive care units (ICUs) have a high incidence of mortality, prolonged hospital length of stay, and living in a dependent state should they survive.

Objective: The objective was to develop a clinical prediction tool for hospital mortality to improve future end-of-life decision making for very elderly patients who are admitted to Canadian ICUs.

Design: This was a prospective, multicenter cohort study.

The adequacy of timely empiric antibiotic therapy for ventilator-associated pneumonia: an important determinant of outcome.

Objective: The individual impact of timeliness vs adequacy of empiric antibiotic therapy for a clinical suspicion of ventilator-associated pneumonia (CSVAP) is unknown. Accordingly, in patients with CSVAP and timely initiation of empiric antibiotic therapy, we determined the impact of inadequate therapy (IT).

Methods: Analysis of a randomized trial of CSVAP treated empirically with meropenem or meropenem plus ciprofloxacin was done.

Mortality, attributable mortality, and clinical events as end points for clinical trials of ventilator-associated pneumonia and hospital-acquired pneumonia.

Appropriate end points are crucial for the successful interpretation of clinical trials. Choosing end points for therapeutic trials of ventilator-associated pneumonia (VAP) and hospital-acquired pneumonia (HAP) requires careful consideration, because they are complications of critical illness. It may be difficult to distinguish the consequences of VAP and HAP from manifestations of the underlying illnesses, and it is important to determine their incremental magnitude, to plan for possible treatment effects and, thus, sample size calculations.

Determinants of outcome in patients with a clinical suspicion of ventilator-associated pneumonia.

Introduction: In the absence of a reference standard, a probabilistic approach to the diagnosis of ventilator-associated pneumonia (VAP) has been proposed; and clinician judgment augmented by microbiological tests is used to guide therapy for patients having a clinical suspicion of VAP (CSVAP). However, the correlation of both clinician judgment at the time of CSVAP and the probability of VAP with clinical outcomes is unknown. In a cohort of patients with CSVAP, we sought to determine the correlation of clinician judgment and the probability of VAP with clinical outcomes.

The impact of ventilator-associated pneumonia on the Canadian health care system.

Introduction: Ventilator-associated pneumonia (VAP) is a cause of morbidity and mortality in critically ill patients. It is associated with increased health care costs and duration of mechanical ventilation. Using published data and information from public health care providers, we sought to determine the impact of VAP on the Canadian health care system.

Venous thromboembolism in critical illness in a community intensive care unit.

Background: Venous thromboembolism (VTE) can be a life-threatening complication of critical illness. Venous thromboembolism rates observed depend on the population studied, the screening modality used, and thromboprophylaxis prescribed. Few studies report on the rates of clinically diagnosed VTE in critically ill patients.