N. David Yanez

Randomized trial of light versus deep sedation on mental health after critical illness

Objectives:To investigate if light sedation favorably affects subsequent patient mental health compared with deep sedation. Symptoms of posttraumatic stress disorder are common in patients after they have undergone prolonged mechanical ventilation and are associated with sedation depth. Design:Randomized, open-label, controlled trial. Setting:Single tertiary care center. Patients:Adult patients requiring mechanical ventilation. Interventions:Patients were randomized to receive either light (patient awake and cooperative) or deep sedation (patient asleep, awakening upon physical stimulation). Measurements and Main Results:Self-reported measures of posttraumatic stress disorder, anxiety, and depression were collected at intensive care unit discharge and 4 wks later. The primary outcomes were symptoms of posttraumatic stress disorder, anxiety, and depression 4 wks after intensive care unit discharge. A total of 137 patients were assigned to either the light (n = 69) or the deep sedation (n = 68) group. Seven patients withdrew consent and one patient was randomized in error, leaving 129 patients (n = 65 in light sedation and n = 64 in deep sedation) available for analysis. At the 4-wk follow-up, patients in the deep sedation group tended to have more posttraumatic stress disorder symptoms (p = .07); the deep sedation group had more trouble remembering the event (37% vs. 14%; p = .02) and more disturbing memories of the intensive care unit (18% vs. 4%; p = .05). Patients in the light sedation group had an average one day less being ventilated and 1.5 fewer days in the intensive care unit. There were no differences between the two groups in the occurrence of anxiety and depression, and also no difference in mortality or in the incidence of adverse events. Conclusions:These data suggest that a strategy of light sedation affords benefits with regard to reduction of intensive care unit stay and duration of ventilation without negatively affecting subsequent patient mental health or patient safety.

Prevalence, predisposing factors, and prognosis of clinically unrecognized myocardial infarction in the elderly ☆

OBJECTIVES This study was designed to determine the prevalence of unrecognized myocardial infarction (UMI), as well as risk factors, and to compare prognosis after detection of previously UMI to that after recognized myocardial infarction (RMI). BACKGROUND Past studies revealed that a significant proportion of MIs escape recognition, and that prognosis after such events is poor, but the epidemiology of UMI has not been reassessed in the contemporary era. METHODS The Cardiovascular Health Study (CHS) database, composed of individuals > or =65, was queried for participants who, at entry, demonstrated electrocardiographic evidence of a prior Q-wave MI, but who lacked a history of this diagnosis. The features and outcomes of this group were compared to those of individuals with prevalent RMI. RESULTS Of 5,888 participants, 901 evidenced a past MI, and 201 (22.3%) were previously unrecognized. The independent predictors of UMI were the absence of angina and the absence of congestive heart failure (CHF). Six-year mortality did not significantly differ between the two groups. CONCLUSIONS 1) In the elderly, UMI continues to represent a significant proportion of all MIs; 2) associations with angina and CHF may reflect complex neurological issues, but they also may represent diagnosis bias; 3) these individuals can otherwise not be distinguished from those with recognized infarctions; and 4) mortality rates after UMI and RMI are similar. Future studies should address screening for UMI, risk stratification after detection of previously UMI, and the role of standard post-MI therapies.

Intensive insulin therapy and mortality in critically ill patients.

IntroductionIntensive insulin therapy (IIT) with tight glycemic control may reduce mortality and morbidity in critically ill patients and has been widely adopted in practice throughout the world. However, there is only one randomized controlled trial showing unequivocal benefit to this approach and that study population was dominated by post-cardiac surgery patients. We aimed to determine the association between IIT and mortality in a mixed population of critically ill patients.MethodsWe conducted a cohort study comparing three consecutive time periods before and after IIT protocol implementation in a Level 1 trauma center: period I (no protocol); period II, target glucose 80 to 130 mg/dL; and period III, target glucose 80 to 110 mg/dL. Subjects were 10,456 patients admitted to intensive care units (ICUs) between 1 March 2001 and 28 February 2005. The main study endpoints were ICU and hospital mortality, Sequential Organ Failure Assessment score, and occurrence of hypoglycemia. Multivariable regression analysis was used to evaluate mortality and organ dysfunction during periods II and III relative to period I.ResultsInsulin administration increased over time (9% period I, 25% period II, and 42% period III). Nonetheless, patients in period III had a tendency toward higher adjusted hospital mortality (odds ratio [OR] 1.15, 95% confidence interval [CI] 0.98, 1.35) than patients in period I. Excess hospital mortality in period III was present primarily in patients with an ICU length of stay of 3 days or less (OR 1.47, 95% CI 1.11, 1.93 There was an approximately fourfold increase in the incidence of hypoglycemia from periods I to III.ConclusionA policy of IIT in a group of ICUs from a single institution was not associated with a decrease in hospital mortality. These results, combined with the findings from several recent randomized trials, suggest that further study is needed prior to widespread implementation of IIT in critically ill patients.

Management guided by brain tissue oxygen monitoring and outcome following severe traumatic brain injury.

OBJECT The authors sought to describe changes in clinical management associated with brain tissue oxygen (PbO(2)) monitoring and how these changes affected outcomes and resource utilization. METHODS The cohort study comprised 629 patients admitted to a Level I trauma center with a diagnosis of severe traumatic brain injury over a period of 3 years. Hospital mortality rate, neurological outcome, and resource utilization of 123 patients who underwent both PbO(2) and intracranial pressure (ICP) monitoring were compared with the same measures in 506 patients who underwent ICP monitoring only. The main outcomes were hospital mortality rate, functional independence at hospital discharge, duration of mechanical ventilation, hospital length of stay, and hospital cost. Multivariable regression with robust variance was used to estimate the adjusted differences in the main outcome measures between patient groups. The models were adjusted for patient age, severity of injury, and pathological features seen on head CT scan at admission. RESULTS On average, patients who underwent ICP/PbO(2) monitoring were younger and had more severe injuries than patients who received ICP monitoring alone. Relatively more patients treated with PbO(2) monitoring received osmotic therapy, vasopressors, and prolonged sedation. After adjustment for baseline characteristics, the hospital mortality rate was, if anything, slightly higher in patients undergoing PbO(2)-guided management than in patients monitored with ICP only (adjusted mortality difference 4.4%, 95% CI -3.9 to 13%). Patients who underwent PbO(2)-guided management also had lower adjusted functional independence scores at hospital discharge (adjusted score difference -0.75, 95% CI -1.41 to -0.09). There was a 27% relative increase (95% CI 6-53%) in the median hospital length of stay when the PbO(2) group was compared with the ICP-only group. CONCLUSIONS The mortality rate in patients with traumatic brain injury whose clinical management was guided by PbO(2) monitoring was not reduced in comparison with that in patients who received ICP monitoring alone. Brain tissue oxygen monitoring was associated with worse neurological outcome and increased hospital resource utilization.

Racial Disparities Among Patients With Lung Cancer Who Were Recommended Operative Therapy

HYPOTHESIS Health care system and provider biases and differences in patient characteristics are thought to be prevailing factors underlying racial disparities. The influence of these factors on the receipt of care would likely be mitigated among patients who are recommended optimal therapy. We hypothesized that there would be no significant evidence of racial disparities among patients with early-stage lung cancer who are recommended surgical therapy. DESIGN, SETTING, AND PATIENTS Retrospective cohort study of patients in the Surveillance, Epidemiology, and End Results-Medicare database who were diagnosed with stage I or II lung cancer between January 1, 1992, and December 31, 2002 (follow-up through December 31, 2005). MAIN OUTCOME MEASURES Receipt of lung resection and overall survival. RESULTS Among 17,739 patients who were recommended surgical therapy (mean [SD] age, 75 [5] years; 89% white, 6% black), black patients less frequently underwent resection compared with white patients (69% vs 83%, respectively; P < .001). After adjustment, black race was associated with lower odds of receiving surgical therapy (odds ratio = 0.43; 99% confidence interval, 0.36-0.52). Unadjusted 5-year survival rates were lower for black patients compared with white patients (36% vs 42%, respectively; P < .001). After adjustment, there was no significant association between race and death (hazard ratio = 1.03; 99% confidence interval, 0.92-1.14) despite a 14% difference in receipt of optimal therapy. CONCLUSIONS Even among patients who were recommended surgical therapy, black patients underwent lung resection less often than white patients. Unexpectedly, racial differences in the receipt of optimal therapy did not appear to affect outcomes. These findings suggest that distrust, beliefs and perceptions about lung cancer and its treatment, and limited access to care (despite insurance) might have a more dominant role in perpetuating racial disparities than previously recognized.

The effects of measurement error in response variables and tests of association of explanatory variables in change models

Biomedical studies often measure variables with error. Examples in the literature include investigation of the association between the change in some outcome variable (blood pressure, cholesterol level etc.) and a set of explanatory variables (age, smoking status etc.). Typically, one fits linear regression models to investigate such associations. With the outcome variable measured with error, a problem occurs when we include the baseline value of the outcome variable as a covariate. In such instances, one can find a relationship between the observed change in the outcome and the explanatory variables even when there is no association between these variables and the true change in the outcome variable. We present a simple method of adjusting for a common measurement error bias that tends to be overlooked in the modelling of associations with change. Additional information (for example, replicates, instrumental variables) is needed to estimate the variance of the measurement error to perform this bias correction.

A Regression Model for Longitudinal Change in the Presence of Measurement Error

PURPOSE The analysis of change in measured variables has become quite popular in studies where data are collected repeatedly over time. The authors describe some of the potential pitfalls in the analysis of change when the variable for change is measured with error. They show that regression analysis is often biased, possibly leading to erroneous results. METHODS A simple method to correct for measurement error bias in regression models that model change is presented. RESULTS AND CONCLUSIONS The two examples illustrate how measurement error can adversely affect an analysis. The bias-corrected approach yields valid results.

Improved Analgesia, Sedation, and Delirium Protocol Associated with Decreased Duration of Delirium and Mechanical Ventilation

RATIONALE Introduction of sedation protocols has been associated with improved patient outcomes. It is not known if an update to an existing high-quality sedation protocol, featuring increased patient assessment and reduced benzodiazepine exposure, is associated with improved patient process and outcome quality metrics. METHODS This was an observational before (n = 703) and after (n = 780) cohort study of mechanically ventilated patients in a 24-bed trauma-surgical intensive care unit (ICU) from 2009 to 2011. The three main protocol updates were: (1) requirement to document Richmond Agitation Sedation Scale (RASS) scores every 4 hours, (2) requirement to document Confusion Assessment Method-ICU (CAM ICU) twice daily, and (3) systematic, protocolized deescalation of excess sedation. Multivariable linear regression was used for the primary analysis. The primary outcome was the duration of mechanical ventilation. Prespecified secondary endpoints included days of delirium; the frequency of patient assessment with the RASS and CAM-ICU instruments; benzodiazepine dosing; durations of mechanical ventilation, ICU stay, and hospitalization; and hospital mortality and ventilator associated pneumonia rate. RESULTS Patients in the updated protocol cohort had 1.22 more RASS assessments per day (5.38 vs. 4.16; 95% confidence interval [CI], 1.05-1.39; P < 0.01) and 1.15 more CAM-ICU assessments per day (1.49 vs. 0.35; 95% CI, 1.08-1.21; P < 0.01) than the baseline cohort. The mean hourly benzodiazepine dose decreased by 34.8% (0.08 mg lorazepam equivalents/h; 0.15 vs. 0.23; P < 0.01). In the multivariable model, the median duration of mechanical ventilation decreased by 17.6% (95% CI, 0.6-31.7%; P = 0.04). The overall odds ratio of delirium was 0.67 (95% CI, 0.49-0.91; P = 0.01) comparing updated versus baseline cohort. A 12.4% reduction in median duration of ICU stay (95% CI, 0.5-22.8%; P = 0.04) and a 14.0% reduction in median duration of hospitalization (95% CI, 2.0-24.5%; P = 0.02) were also seen. No significant association with mortality (odds ratio, 1.18; 95% CI, 0.80-1.76; P = 0.40) was seen. CONCLUSIONS Implementation of an updated ICU analgesia, sedation, and delirium protocol was associated with an increase in RASS and CAM-ICU assessment and documentation; reduced hourly benzodiazepine dose; and decreased delirium and median durations of mechanical ventilation, ICU stay, and hospitalization.

The relationship of bottle feeding and other sucking behaviors with speech disorder in Patagonian preschoolers

BackgroundPrevious studies have shown that childrens nonnutritive sucking habits may lead to delayed development of their oral anatomy and functioning. However, these findings were inconsistent. We investigated associations between use of bottles, pacifiers, and other sucking behaviors with speech disorders in children attending three preschools in Punta Arenas (Patagonia), Chile.MethodsInformation on infant feeding and sucking behaviors, age starting and stopping breast- and bottle-feeding, pacifier use, and other sucking behaviors, was collected from self-administered questionnaires completed by parents. Evaluation of speech problems was conducted at preschools with subsequent scoring by a licensed speech pathologist using age-normative standards.ResultsA total of 128 three- to five-year olds were assessed, 46% girls and 54% boys. Children were breastfed for an average of 25.2 (SD 9.6) months and used a bottle 24.4 (SD 15.2) months. Fifty-three children (41.7%) had or currently used a pacifier for an average of 11.4 (SD 17.3) months; 23 children (18.3%) were reported to have sucked their fingers. Delayed use of a bottle until after 9 months appeared to be protective for subsequent speech disorders. There was less than a one-third lower relative odds of subsequent speech disorders for children with a delayed use of a bottle compared to children without a delayed use of a bottle (OR: 0.32, 95% CI: 0.10-0.98). A three-fold increase in relative odds of speech disorder was found for finger-sucking behavior (OR: 2.99, 95% CI: 1.10-8.00) and for use of a pacifier for 3 or more years (OR: 3.42, 95% CI: 1.08-10.81).ConclusionThe results suggest extended use of sucking outside of breastfeeding may have detrimental effects on speech development in young children.

Occurrence and complications of tracheal reintubation in critically ill adults.

BACKGROUND: Timing and preparation for tracheal extubation are as critical as the initial intubation. There are limited data on specific strategies for a planned extubation. The extent to which the difficult airway at reintubation contributes to patient morbidity is unknown. The aim of the present study was to describe the occurrence and complications of failed extubation and associated risk factors, and to estimate the mortality and morbidity associated with reintubation attempts. METHODS: Cohort study of 2,007 critically ill adult patients admitted to the ICU with an ETT. Patients were classified in 2 groups, based on the requirement for reintubation: “never reintubated” versus “≥ 1 reintubations.” Baseline characteristics, ICU and hospital stay, hospital mortality, and in-patient costs were compared between patients successfully extubated and those with reintubation outside the operating room, using regression techniques. Reasons, airway management techniques, and complications of intubation and reintubation were summarized descriptively. RESULTS: 376 patients (19%) required reintubation, and 230 (11%) were reintubated within 48 hours, primarily due to respiratory failure. Patients requiring reintubation were older, more likely to be male, and had higher admission severity score. Difficult intubation and complications were similar for initial and subsequent intubation. Reintubation was associated with a 5-fold increase in the relative odds of death (adjusted odds ratio 5.86, 95% CI 3.87–8.89, P < .01), and a 2-fold increase in median ICU and hospital stay, and institutional costs. Difficult airway at reintubation was associated with higher mortality (adjusted odds ratio 2.23, 95% CI 1.01–4.93, P = .05). CONCLUSIONS: Nearly 20% of critically ill patients required out of operating room reintubation. Reintubation was associated with higher mortality, stay, and cost. Moreover, a difficult airway at reintubation was associated with higher mortality.