Diabetic status and the relation of the three domains of glycemic control to mortality in critically ill patients: an international multicenter cohort study.

INTRODUCTION: Hyperglycemia, hypoglycemia, and increased glycemic variability have each been independently associated with increased risk of mortality in critically ill patients. The role of diabetic status on modulating the relation of these three domains of glycemic control with mortality remains uncertain. The purpose of this investigation was to determine how diabetic status affects the relation of hyperglycemia, hypoglycemia, and increased glycemic variability with the risk of mortality in critically ill patients. METHODS: This is a retrospective analysis of prospectively collected data involving 44,964 patients admitted to 23 intensive care units (ICUs) from nine countries, between February 2001 and May 2012. We analyzed mean blood glucose concentration (BG), coefficient of variation (CV), and minimal BG and created multivariable models to analyze their independent association with mortality. Patients were stratified according to the diagnosis of diabetes. RESULTS: Among patients without diabetes, mean BG bands between 80 and 140 mg/dl were independently associated with decreased risk of mortality, and mean BG bands>or=140 mg/dl, with increased risk of mortality. Among patients with diabetes, mean BG from 80 to 110 mg/dl was associated with increased risk of mortality and mean BG from 110 to 180 mg/dl with decreased risk of mortality. An effect of center was noted on the relation between mean BG and mortality. Hypoglycemia, defined as minimum BG<70 mg/dl, was independently associated with increased risk of mortality among patients with and without diabetes and increased glycemic variability, defined as CV>or=20%, was independently associated with increased risk of mortality only among patients without diabetes. Derangements of more than one domain of glycemic control had a cumulative association with mortality, especially for patients without diabetes. CONCLUSIONS: Although hyperglycemia, hypoglycemia, and increased glycemic variability is each independently associated with mortality in critically ill patients, diabetic status modulates these relations in clinically important ways. Our findings suggest that patients with diabetes may benefit from higher glucose target ranges than will those without diabetes. Additionally, hypoglycemia is independently associated with increased risk of mortality regardless of the patient's diabetic status, and increased glycemic variability is independently associated with increased risk of mortality among patients without diabetes.

Skeletal morbidity among survivors of critical illness.

OBJECTIVES: To describe the incident fracture rate in survivors of critical illness and to compare fracture risk with population-matched control subjects. DESIGN: Retrospective longitudinal case-cohort study. SETTING: A tertiary adult intensive care unit in Australia. PATIENTS: All patients ventilated admitted to intensive care and requiring mechanical ventilation for ≥48 hrs between January 1998 and December 2005. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: New fractures were identified in the study population for the postintensive care unit period (intensive care unit discharge to January 2008). The incident fracture rate and age-adjusted fracture risk of the female intensive care unit population were compared with the general population adult females derived from the Geelong Osteoporosis Study. Over the 8-yr period, a total of 739 patients (258 women, 481 men) were identified. After a median follow-up of 3.7 yrs (interquartile range, 2.0-5.9 yrs) for women and 4.0 yrs (interquartile range, 2.1-6.1 yrs) for men, incident fracture rates (95% confidence interval) per 100 patient years were 3.84 (2.58-5.09) for females 2.41 (1.73-3.09) for males. Compared with an age-matched random population-based sample of women, elderly women were at increased risk for sustaining an osteoporosis-related fracture after critical illness (hazard ratio, 1.65; 95% confidence interval, 1.08-2.52; p = .02). CONCLUSIONS: The increase in fracture risk observed in postintensive care unit older females suggests an association between critical illness and subsequent skeletal morbidity. The explanation for this association is not explored in this study and includes the effects of pre-existing patient factors and/or direct effects of critical illness. Prospective research evaluating risk factors, the relationship between critical illness and bone turnover, the extent and duration of bone loss, and the associated morbidity in this population is warranted.

Designing and implementing an Australian and New Zealand intensive care data audit study.

PURPOSE: The aim of this pilot audit study is to develop and test a model to examine existing adult patient database (APD) data quality. DESIGN/METHODOLOGY/APPROACH: A database was created to audit 50 records per site to determine accuracy. The audited records were randomly selected from the calendar year 2004 and four sites participated in the pilot audit study. A total of 41 data elements were assessed for data quality--those elements required for APACHE II scoring system. FINDINGS: Results showed that the audit was feasible; missing audit data were an unplanned problem; analysis was complicated owing to the way the APACHE calculations are performed and 50 records per site was too time-consuming. ORIGINALITY/VALUE: This is the first audit study of intensive care data within the ANZICS APD and demonstrates how to determine data quality in a large database containing individual patient records.

Incidence of catheter-related bloodstream infection among patients with a needleless, mechanical valve-based intravenous connector in an Australian hematology-oncology unit.

There are few Australian data on the incidence of catheter-associated bloodstream infection (BSI) among patients in hematology-oncology units. We found an increase in catheter-associated BSI rates coincident with the introduction of a mechanical valve connector (2.6 infections vs 5.8 infections per 1,000 catheter-days; incidence rate ratio, 2.2; P=.031).

Development and implementation of a high-quality clinical database: the Australian and New Zealand Intensive Care Society Adult Patient Database.

OBJECTIVE: To describe the development of a binational intensive care database. SETTING: One hundred thirty-eight intensive care units (ICUs) in Australia and New Zealand. METHODS: A structure was developed to enable ICUs to submit data for central and local analysis. Reports were developed to allow comparison with similar ICU types and against published mortality prediction models. The database was evaluated according to (a) the criteria of the Directory of Clinical Databases (DoCDat) and (b) a proposed framework for data quality assurance in medical registries. RESULTS: Between January 1987 and December 2003, 444,147 data sets were collected from 121 (72.5%) of 167 Australian and 10 (37.0%) of 27 New Zealand ICUs. Data sets from more than 60000 ICU admissions were submitted in 2003. Overall hospital mortality was 14.5%. The mean quality level achieved according to DoCDat criteria was high as was performance against a proposed framework for data quality. The provision of no-cost software has been vitally important to the success of the database. CONCLUSION: A high-quality ICU database has successfully been implemented in Australia and New Zealand and is now used as a routine quality assurance and peer review tool. Similar developments may be both possible and desirable in other countries.

Blood glucose on day of intensive care unit admission as a surrogate of subsequent glucose control in intensive care.

PURPOSE: The aim of the study was to test whether the mean of the highest and lowest glucose values on day 1 (Glu(1)) is a useful surrogate marker of mean blood glucose during the totality of intensive care unit (ICU) stay (Glu(tot)). MATERIALS AND METHODS: Glu(tot) values were extracted from electronically stored biochemical databases (point-of-care laboratory) and Glu(1) values from electronically stored prospectively collected patient databases in ICUs of 4 hospitals from January 2000 to October 2004. Statistical assessment of relationship between Glu(1) and Glu(tot) was done. RESULTS: There were 197227 blood glucose measurements for 8039 patients. The average of all blood glucose measurements was 8.22 +/- 2.75 mmol/L. The difference between the average of all glucose values (N = 197227) and average of Glu(1) (n = 8039) was 0.17 mmol/L. This difference in each hospital was also small (0.26, -0.13, 0.12, and 0.37 mmol/L, respectively). CONCLUSIONS: Glu(1) was a good predictor of Glu(tot) across all study hospitals. This observation makes it possible to use Glu(1) as a surrogate of glucose control during ICU stay and opens the door to understanding ICU glucose control across the whole of Australia and New Zealand.

Insurance status and mortality in critically ill patients.

OBJECTIVE: The association between insurance status and outcome in critically ill patients is uncertain. We aimed to determine if there was an independent relationship between the presence or absence of compensable insurance status and mortality, after admission to the intensive care unit. METHODS: We performed a retrospective cohort study in five public hospitals in Victoria, comprising adult patients admitted to the ICU between 2007 and 2012. We obtained data on demographics, severity of illness, chronic health status, insurance category, length of stay (LOS) and mortality. We matched socio-economic indices (collected from the Australian Bureau of Statistics) to postcodes. The primary outcome measured was in-hospital mortality. Secondary outcomes were ICU mortality, and ICU and hospital LOS, measured in days. RESULTS: We studied 33 306 patients. Compensable patients comprised 21.2% of the study population (7046). Personal private insurance accounted for 13.4% (4451) and Transport Accident Commission insurance for 5.1% (1701) of compensable patients. Unadjusted in-hospital mortality was higher in publicly insured patients (13.4% v 10.6%, P < 0.0001). After adjusting for age, severity of illness, diagnosis and socio-economic status, being a compensable patient in a public hospital ICU was independently associated with a reduction in mortality (odds ratio, 0.73; 95% CI, 0.65-0.80; P < 0.001). CONCLUSIONS: Among ICU patients treated in public hospitals in Victoria, being a compensable patient appears to be independently associated with a reduction in mortality. Further studies are needed to confirm and validate these findings elsewhere in Australia.

EMLA cream in the treatment of post-herpetic neuralgia. Efficacy and pharmacokinetic profile.

The analgesic efficacy of 5% of EMLA cream (5 or 10 g) when applied for 24 h periods was evaluated in 5 female and 7 male patients (mean age 69 years, range 50-85 years) with refractory post-herpetic neuralgia (PHN). Mean visual analogue pain intensity scores for all patients were significantly improved 6 h after application (P less than 0.05). In a subgroup of patients with facial PHN receiving EMLA cream, 5 g (n = 4), there were significant improvements in pain intensity scores at 6 h (P less than 0.05). 8 h (P less than 0.01) and 10 h (P less than 0.01) after application. Plasma lignocaine and plasma prilocaine concentrations were well below potentially toxic levels in all patients after application.

Arterial carbon dioxide tension and outcome in patients admitted to the intensive care unit after cardiac arrest.

BACKGROUND: Arterial carbon dioxide tension (PaCO2) affects neuronal function and cerebral blood flow. However, its association with outcome in patients admitted to intensive care unit (ICU) after cardiac arrest (CA) has not been evaluated. METHODS AND RESULTS: Observational cohort study using data from the Australian New Zealand (ANZ) Intensive Care Society Adult-Patient-Database (ANZICS-APD). Outcomes analyses were adjusted for illness severity, co-morbidities, hypothermia, treatment limitations, age, year of admission, glucose, source of admission, PaO2 and propensity score. We studied 16,542 consecutive patients admitted to 125 ANZ ICUs after CA between 2000 and 2011. Using the APD-PaCO2 (obtained within 24 h of ICU admission), 3010 (18.2%) were classified into the hypo- (PaCO2<35 mmHg), 6705 (40.5%) into the normo- (35-45 mmHg) and 6827 (41.3%) into the hypercapnia (>45 mmHg) group. The hypocapnia group, compared with the normocapnia group, had a trend toward higher in-hospital mortality (OR 1.12 [95% CI 1.00-1.24, p=0.04]), lower rate of discharge home (OR 0.81 [0.70-0.94, p<0.01]) and higher likelihood of fulfilling composite adverse outcome of death and no discharge home (OR 1.23 [1.10-1.37, p<0.001]). In contrast, the hypercapnia group had similar in-hospital mortality (OR 1.06 [0.97-1.15, p=0.19]) but higher rate of discharge home among survivors (OR 1.16 [1.03-1.32, p=0.01]) and similar likelihood of fulfilling the composite outcome (OR 0.97 [0.89-1.06, p=0.52]). Cox-proportional hazards modelling supported these findings. CONCLUSIONS: Hypo- and hypercapnia are common after ICU admission post-CA. Compared with normocapnia, hypocapnia was independently associated with worse clinical outcomes and hypercapnia a greater likelihood of discharge home among survivors.

Critical care outcome prediction equation (COPE) for adult intensive care.

OBJECTIVE: Development and validation of a critical care outcome prediction equation (COPE) using data that are collected routinely for administrative purposes. DESIGN: Retrospective observational study using multivariate logistic regression modelling. Calibration and discrimination were assessed by standardised mortality ratio (SMR), area under the receiver operating characteristic plot (ROC AUC), and Hosmer-Lemeshow contingency tables. SETTING: All intensive care units in the state of Victoria, Australia. PARTICIPANTS: Consecutive adult hospital episodes between 1 July 2004 and 30 June 2006. RESULTS: 17 880 records (1 July 2004 - 30 June 2005) were used to derive the COPE model, which incorporated five variables (age, unplanned admission, mechanical ventilation, hospital category and admission diagnosis) and was validated on the 17 848 records from the following year (1 July 2005 - 30 June 2006). The 95% confidence interval of the SMR in the validation sample was 1.00-1.01, and for the ROC AUC was 0.83-0.84. The COPE model was validated in three major hospital categories (tertiary, metropolitan, and regional) and in five individual ICUs, and compared favourably to the APACHE III model (SMR = 0.83- 0.86; ROC AUC = 0.87-0.88). CONCLUSION: The COPE model is a simple, robust, riskadjusted outcome prediction tool based on five fields from data that are routinely collected for administrative purposes.

Implementation and outcomes of a severe sepsis protocol in an Australian tertiary hospital.

OBJECTIVE: To evaluate the effect of implementation of a sepsis protocol. DESIGN: Before and after cohort study. SETTING: Level III ICU in a tertiary regional hospital, February - July, 2006 (before intervention) and 2007 (after). PARTICIPANTS: Adult patients who fulfilled criteria for severe sepsis or septic shock within 48 hours of ICU admission. INTERVENTION: Implementation of a locally modified sepsis protocol. MAIN OUTCOME MEASURES: Delivery of process of care components, and ICU and hospital mortality. RESULTS: A total of 110 patients were included in the study: 44 in the pre-protocol group, and 66 in the post-protocol group. Demographic variables and severity of illness variables were similar in the two groups except for a lower incidence of respiratory sepsis in the post-protocol group. Post-protocol, there was a shorter time to initiation of appropriate antibiotics, and an increase in the use of vasopressors, deep vein thrombosis prophylaxis, and nutritional support, with no difference in ICU or hospital mortality. There was no difference in resuscitation endpoints at 6, 24, and 72 hours. CONCLUSIONS: Implementation of a sepsis protocol led to a change in the delivery of care with no reduction in mortality in patients with severe sepsis and septic shock admitted to a Level III ICU in a tertiary hospital.

Monitoring the rate of re-exploration for excessive bleeding after cardiac surgery in adults.

BACKGROUND: The monitoring of adverse events in clinical care can be an important part of quality assurance. There is little evidence on the monitoring of re-exploration after cardiac surgery. OBJECTIVE: To apply statistical monitoring techniques to the rate of re-exploration for excessive bleeding in adult patients undergoing cardiac surgery procedures using cardiopulmonary bypass at Geelong Hospital, Victoria, Australia, between 1997 and 2003. METHODS: Shewhart charts, moving average plots and cumulative sum (CUSUM) charts were used to demonstrate changes in the rate of re-exploration over time. RESULTS: A CUSUM chart was used retrospectively at a time of perceived deteriorating clinical outcomes in patients of the cardiac surgery service. At this time, an intervention aimed at reducing the re-exploration rate was performed, and subsequent CUSUM charts indicated an improvement in this rate. The CUSUM chart has become an important part of the quality feedback of clinical care outcomes within the Anaesthesia & Pain Management unit of Geelong Hospital. CONCLUSION: Statistical monitoring techniques for quality assurance can identify important changes in clinical performance, and their adoption by clinicians is recommended.

Why is there such a difference in outcome between Australian intensive care units and others?

PURPOSE OF REVIEW: The aim of this article is to assess the data on clinical outcomes for critically ill patients admitted to Australian and New Zealand intensive care units in comparison to information available for similar patients in other counties RECENT FINDINGS: Australia and New Zealand have been collecting standardized data intensive care unit admissions for over a decade. The Australian and New Zealand Intensive Care Society Database Management Committee has developed a high quality database of close to 600 000 adult intensive care unit admissions. Although comparisons suffer from significant methodological, case-mix and process differences, which make their findings easily subject to criticism, interrogation of this database and of data from clusters of intensive care units within this system consistently yields patient outcomes, which are better than outcomes reported from other nations or international studies for similar patients. In addition, Australia and New Zealand has now achieved the highest rate of patient enrollment in an investigator-initiated multicentre randomized controlled trials. SUMMARY: Although comparisons in outcome between Australia and New Zealand intensive care units and other units worldwide may not have sufficient scientific rigour to truly reflect better national outcomes, many features of Australian and New Zealand units are unique and worthy of consideration by other national systems as they consider their strategic national goals for the next decade.

Circadian rhythm of blood glucose values in critically ill patients.

OBJECTIVE: To test whether there is a circadian rhythm of blood glucose control in critically ill patients and whether morning blood glucose is an accurate surrogate of overall blood glucose control. DESIGN: Retrospective multiple-center observational study. SETTING: Intensive care units of three tertiary hospitals and one affiliated private hospital. PATIENTS: Cohort of 8,307 consecutive critically ill patients. INTERVENTIONS: Extraction of blood glucose values from electronically stored measurements. Extraction of demographic and outcome data from unit and hospital databases. Statistical assessment of variations in blood glucose control over each 24-hr cycle. MEASUREMENTS AND MAIN RESULTS: We studied 208,362 blood glucose measurements in 8,307 patients (5.5 measurements/day/person). In each hospital, there was a circadian rhythm of blood glucose control (p<.0001). The differences between highest and lowest blood glucose concentration in different time periods in each hospital were 0.27, 0.28, 0.95, and 0.22 mmol/L. There was also significant variation in the incidence and notional duration of hyperglycemia. The differences between the lowest and highest incidence of hyperglycemia in different time periods were 3.3, 2.7, 9.9, and 2.6% in each hospital. In all four hospitals, the average blood glucose value from 5:30 am to 6:30 am was significantly lower than the 24-hr average. CONCLUSIONS: Blood glucose values and the incidence of hyperglycemia have a circadian rhythm in critically ill patients. Morning blood glucose may not be an accurate surrogate of blood glucose control over the daily cycle.

Improved outcomes from acute severe asthma in Australian intensive care units (1996 2003).

BACKGROUND: There is limited information on changes in the epidemiology and outcome of patients with asthma admitted to intensive care units (ICUs) in the last decade. A database sampling intensive care activity in hospitals throughout Australia offers the opportunity to examine these changes. METHODS: The Australian and New Zealand Intensive Care Society Adult Patient Database was examined for all patients with asthma admitted to ICUs from 1996 to 2003. Demographic, physiological and outcome information was obtained and analysed from 22 hospitals which had submitted data continuously over this period. RESULTS: ICU admissions with the primary diagnosis of asthma represented 1899 (1.5%) of 126 906 admissions during the 8-year period. 36.1% received mechanical ventilation during the first 24 h. The overall incidence of admission to ICU fell from 1.9% in 1996 to 1.1% in 2003 (p<0.001). Overall hospital mortality was 3.2%. There was a significant decline in mortality from a peak of 4.7% in 1997 to 1.1% in 2003 (p = 0.014). This was despite increasing severity of illness (as evidenced by an increasing predicted risk of death derived from the APACHE II score) over the 8-year period (p = 0.002). CONCLUSIONS: There has been a significant decline in the incidence of asthma requiring ICU admission between 1996 and 2003 among units sampled by the Australian and New Zealand Intensive Care Society Adult Patient Database. The mortality of these patients has also decreased over time and is lower than reported in other studies.

Intensive insulin therapy in postoperative intensive care unit patients: a decision analysis.

RATIONALE: Intensive insulin therapy (IIT) may reduce mortality in mechanically ventilated postoperative patients. OBJECTIVES: To assess the risks and benefits of IIT in different institutions. DESIGN: Retrospective, blinded-to-outcome selection of patient cohorts from four hospitals. METHODS: Selection of a cohort of patients with clinical features similar to those reported in a recent study of IIT and of all mechanically ventilated postoperative patients from each hospital. Retrieval of information on glucose control. Assessment of risks and benefits and final outcomes. MEASUREMENTS AND MAIN RESULTS: We selected 783 consecutive patients with similar clinical and demographic features to the IIT trial control group and four general cohorts for a total of 4,150 consecutive mechanically ventilated postoperative patients. In these patients, glucose levels were measured 212,663 times for a mean value of 8.22 +/- 2.7 mmol/L (148 +/- 49 mg/dl). Intensive care unit (ICU) mortality varied from 2.2 to 13.6%. The incidence of hypoglycemia (defined as < 2.2 mmol/L) varied from 1.4 to 2.7%. Assuming a beneficial effect of IIT as reported, the number needed to treat to save one life varied from 38 in one ICU to 125 in another, whereas the rate of hypoglycemia (number needed to harm) varied from 7 to 13. CONCLUSIONS: The number needed to treat to prevent an ICU death and the associated risk of hypoglycemia (number needed to harm) with IIT vary widely according to baseline mortality, case mix, and case selection. Rational decision analysis in individual ICUs should take these factors into account.

Early audit of renal complications in a new cardiac surgery service in Australia.

OBJECTIVE: To assess the incidence of renal failure in a cardiac surgery service commencing in Australia. DESIGN: Prospective data collection and retrospective database analysis. SETTING: A tertiary referral, university teaching hospital in the state of Victoria, Australia. PARTICIPANTS: The first 502 patients undergoing cardiac surgery in this institution from commencement of the service. RESULTS: The overall rate of renal failure was low in comparison to other studies at 0.2% (95% CI 0.04-1.3%). The rate of postoperative renal dysfunction was also low at 4.2% (95% CI 2.7-6.5%). CONCLUSIONS: The safety of the new service with respect to this complication of cardiac surgery was good when compared with published data. However the lack of uniform definitions of renal failure following cardiac surgery make comparisons between studies difficult. Uniform reporting of this complication would facilitate comparisons between units and quality assurance activities in this field.