David James Cooper

Critical care services and 2009 H1N1 influenza in Australia and New Zealand

BACKGROUND Planning for the treatment of infection with the 2009 pandemic influenza A (H1N1) virus through health care systems in developed countries during winter in the Northern Hemisphere is hampered by a lack of information from similar health care systems. METHODS We conducted an inception-cohort study in all Australian and New Zealand intensive care units (ICUs) during the winter of 2009 in the Southern Hemisphere. We calculated, per million inhabitants, the numbers of ICU admissions, bed-days, and days of mechanical ventilation due to infection with the 2009 H1N1 virus. We collected data on demographic and clinical characteristics of the patients and on treatments and outcomes. RESULTS From June 1 through August 31, 2009, a total of 722 patients with confirmed infection with the 2009 H1N1 virus (28.7 cases per million inhabitants; 95% confidence interval [CI], 26.5 to 30.8) were admitted to an ICU in Australia or New Zealand. Of the 722 patients, 669 (92.7%) were under 65 years of age and 66 (9.1%) were pregnant women; of the 601 adults for whom data were available, 172 (28.6%) had a body-mass index (the weight in kilograms divided by the square of the height in meters) greater than 35. Patients infected with the 2009 H1N1 virus were in the ICU for a total of 8815 bed-days (350 per million inhabitants). The median duration of treatment in the ICU was 7.0 days (interquartile range, 2.7 to 13.4); 456 of 706 patients (64.6%) with available data underwent mechanical ventilation for a median of 8 days (interquartile range, 4 to 16). The maximum daily occupancy of the ICU was 7.4 beds (95% CI, 6.3 to 8.5) per million inhabitants. As of September 7, 2009, a total of 103 of the 722 patients (14.3%; 95% CI, 11.7 to 16.9) had died, and 114 (15.8%) remained in the hospital. CONCLUSIONS The 2009 H1N1 virus had a substantial effect on ICUs during the winter in Australia and New Zealand. Our data can assist planning for the treatment of patients during the winter in the Northern Hemisphere.

Goal-directed resuscitation for patients with early septic shock.

BACKGROUND Early goal-directed therapy (EGDT) has been endorsed in the guidelines of the Surviving Sepsis Campaign as a key strategy to decrease mortality among patients presenting to the emergency department with septic shock. However, its effectiveness is uncertain. METHODS In this trial conducted at 51 centers (mostly in Australia or New Zealand), we randomly assigned patients presenting to the emergency department with early septic shock to receive either EGDT or usual care. The primary outcome was all-cause mortality within 90 days after randomization. RESULTS Of the 1600 enrolled patients, 796 were assigned to the EGDT group and 804 to the usual-care group. Primary outcome data were available for more than 99% of the patients. Patients in the EGDT group received a larger mean (±SD) volume of intravenous fluids in the first 6 hours after randomization than did those in the usual-care group (1964±1415 ml vs. 1713±1401 ml) and were more likely to receive vasopressor infusions (66.6% vs. 57.8%), red-cell transfusions (13.6% vs. 7.0%), and dobutamine (15.4% vs. 2.6%) (P<0.001 for all comparisons). At 90 days after randomization, 147 deaths had occurred in the EGDT group and 150 had occurred in the usual-care group, for rates of death of 18.6% and 18.8%, respectively (absolute risk difference with EGDT vs. usual care, -0.3 percentage points; 95% confidence interval, -4.1 to 3.6; P=0.90). There was no significant difference in survival time, in-hospital mortality, duration of organ support, or length of hospital stay. CONCLUSIONS In critically ill patients presenting to the emergency department with early septic shock, EGDT did not reduce all-cause mortality at 90 days. (Funded by the National Health and Medical Research Council of Australia and the Alfred Foundation; ARISE ClinicalTrials.gov number, NCT00975793.).

Systemic Inflammatory Response Syndrome Criteria in Defining Severe Sepsis

BACKGROUND The consensus definition of severe sepsis requires suspected or proven infection, organ failure, and signs that meet two or more criteria for the systemic inflammatory response syndrome (SIRS). We aimed to test the sensitivity, face validity, and construct validity of this approach. METHODS We studied data from patients from 172 intensive care units in Australia and New Zealand from 2000 through 2013. We identified patients with infection and organ failure and categorized them according to whether they had signs meeting two or more SIRS criteria (SIRS-positive severe sepsis) or less than two SIRS criteria (SIRS-negative severe sepsis). We compared their characteristics and outcomes and assessed them for the presence of a step increase in the risk of death at a threshold of two SIRS criteria. RESULTS Of 1,171,797 patients, a total of 109,663 had infection and organ failure. Among these, 96,385 patients (87.9%) had SIRS-positive severe sepsis and 13,278 (12.1%) had SIRS-negative severe sepsis. Over a period of 14 years, these groups had similar characteristics and changes in mortality (SIRS-positive group: from 36.1% [829 of 2296 patients] to 18.3% [2037 of 11,119], P<0.001; SIRS-negative group: from 27.7% [100 of 361] to 9.3% [122 of 1315], P<0.001). Moreover, this pattern remained similar after adjustment for baseline characteristics (odds ratio in the SIRS-positive group, 0.96; 95% confidence interval [CI], 0.96 to 0.97; odds ratio in the SIRS-negative group, 0.96; 95% CI, 0.94 to 0.98; P=0.12 for between-group difference). In the adjusted analysis, mortality increased linearly with each additional SIRS criterion (odds ratio for each additional criterion, 1.13; 95% CI, 1.11 to 1.15; P<0.001) without any transitional increase in risk at a threshold of two SIRS criteria. CONCLUSIONS The need for two or more SIRS criteria to define severe sepsis excluded one in eight otherwise similar patients with infection, organ failure, and substantial mortality and failed to define a transition point in the risk of death. (Funded by the Australian and New Zealand Intensive Care Research Centre.).

Early Parenteral Nutrition in Critically Ill Patients With Short-term Relative Contraindications to Early Enteral Nutrition: A Randomized Controlled Trial

IMPORTANCE Systematic reviews suggest adult patients in intensive care units (ICUs) with relative contraindications to early enteral nutrition (EN) may benefit from parenteral nutrition (PN) provided within 24 hours of ICU admission. OBJECTIVE To determine whether providing early PN to critically ill adults with relative contraindications to early EN alters outcomes. DESIGN, SETTING, AND PARTICIPANTS Multicenter, randomized, single-blind clinical trial conducted between October 2006 and June 2011 in ICUs of 31 community and tertiary hospitals in Australia and New Zealand. Participants were critically ill adults with relative contraindications to early EN who were expected to remain in the ICU longer than 2 days. INTERVENTIONS Random allocation to pragmatic standard care or early PN. MAIN OUTCOMES AND MEASURES Day-60 mortality; quality of life, infections, and body composition. RESULTS A total of 1372 patients were randomized (686 to standard care, 686 to early PN). Of 682 patients receiving standard care, 199 patients (29.2%) initially commenced EN, 186 patients (27.3%) initially commenced PN, and 278 patients (40.8%) remained unfed. Time to EN or PN in patients receiving standard care was 2.8 days (95% CI, 2.3 to 3.4). Patients receiving early PN commenced PN a mean of 44 minutes after enrollment (95% CI, 36 to 55). Day-60 mortality did not differ significantly (22.8% for standard care vs 21.5% for early PN; risk difference, -1.26%; 95% CI, -6.6 to 4.1; P = .60). Early PN patients rated day-60 quality of life (RAND-36 General Health Status) statistically, but not clinically meaningfully, higher (45.5 for standard care vs 49.8 for early PN; mean difference, 4.3; 95% CI, 0.95 to 7.58; P = .01). Early PN patients required fewer days of invasive ventilation (7.73 vs 7.26 days per 10 patient × ICU days, risk difference, -0.47; 95% CI, -0.82 to -0.11; P = .01) and, based on Subjective Global Assessment, experienced less muscle wasting (0.43 vs 0.27 score increase per week; mean difference, -0.16; 95% CI, -0.28 to -0.038; P = .01) and fat loss (0.44 vs 0.31 score increase per week; mean difference, -0.13; 95% CI, -0.25 to -0.01; P = .04). CONCLUSIONS AND RELEVANCE The provision of early PN to critically ill adults with relative contraindications to early EN, compared with standard care, did not result in a difference in day-60 mortality. The early PN strategy resulted in significantly fewer days of invasive ventilation but not significantly shorter ICU or hospital stays. TRIAL REGISTRATION anzctr.org.au Identifier: ACTRN012605000704695.

Dalteparin versus unfractionated heparin in critically ill patients.

BACKGROUND The effects of thromboprophylaxis with low-molecular-weight heparin, as compared with unfractionated heparin, on venous thromboembolism, bleeding, and other outcomes are uncertain in critically ill patients. METHODS In this multicenter trial, we tested the superiority of dalteparin over unfractionated heparin by randomly assigning 3764 patients to receive either subcutaneous dalteparin (at a dose of 5000 IU once daily) plus placebo once daily (for parallel-group twice-daily injections) or unfractionated heparin (at a dose of 5000 IU twice daily) while they were in the intensive care unit. The primary outcome, proximal leg deep-vein thrombosis, was diagnosed on compression ultrasonography performed within 2 days after admission, twice weekly, and as clinically indicated. Additional testing for venous thromboembolism was performed as clinically indicated. Data were analyzed according to the intention-to-treat principle. RESULTS There was no significant between-group difference in the rate of proximal leg deep-vein thrombosis, which occurred in 96 of 1873 patients (5.1%) receiving dalteparin versus 109 of 1873 patients (5.8%) receiving unfractionated heparin (hazard ratio in the dalteparin group, 0.92; 95% confidence interval [CI], 0.68 to 1.23; P=0.57). The proportion of patients with pulmonary emboli was significantly lower with dalteparin (24 patients, 1.3%) than with unfractionated heparin (43 patients, 2.3%) (hazard ratio, 0.51; 95% CI, 0.30 to 0.88; P=0.01). There was no significant between-group difference in the rates of major bleeding (hazard ratio, 1.00; 95% CI, 0.75 to 1.34; P=0.98) or death in the hospital (hazard ratio, 0.92; 95% CI, 0.80 to 1.05; P=0.21). In prespecified per-protocol analyses, the results were similar to those of the main analyses, but fewer patients receiving dalteparin had heparin-induced thrombocytopenia (hazard ratio, 0.27; 95% CI, 0.08 to 0.98; P=0.046). CONCLUSIONS Among critically ill patients, dalteparin was not superior to unfractionated heparin in decreasing the incidence of proximal deep-vein thrombosis. (Funded by the Canadian Institutes of Health Research and others; PROTECT ClinicalTrials.gov number, NCT00182143.).

Prehospital Rapid Sequence Intubation Improves Functional Outcome for Patients With Severe Traumatic Brain Injury: A Randomized Controlled Trial

Objective: To determine whether paramedic rapid sequence intubation in patients with severe traumatic brain injury (TBI) improves neurologic outcomes at 6 months compared with intubation in the hospital. Background: Severe TBI is associated with a high rate of mortality and long-term morbidity. Comatose patients with TBI routinely undergo endo-tracheal intubation to protect the airway, prevent hypoxia, and control ventilation. In many places, paramedics perform intubation prior to hospital arrival. However, it is unknown whether this approach improves outcomes. Methods: In a prospective, randomized, controlled trial, we assigned adults with severe TBI in an urban setting to either prehospital rapid sequence intubation by paramedics or transport to a hospital emergency department for intubation by physicians. The primary outcome measure was the median extended Glasgow Outcome Scale (GOSe) score at 6 months. Secondary end-points were favorable versus unfavorable outcome at 6 months, length of intensive care and hospital stay, and survival to hospital discharge. Results: A total of 312 patients with severe TBI were randomly assigned to paramedic rapid sequence intubation or hospital intubation. The success rate for paramedic intubation was 97%. At 6 months, the median GOSe score was 5 (interquartile range, 1–6) in patients intubated by paramedics compared with 3 (interquartile range, 1–6) in the patients intubated at hospital (P = 0.28). The proportion of patients with favorable outcome (GOSe, 5–8) was 80 of 157 patients (51%) in the paramedic intubation group compared with 56 of 142 patients (39%) in the hospital intubation group (risk ratio, 1.28; 95% confidence interval, 1.00–1.64; P = 0.046). There were no differences in intensive care or hospital length of stay, or in survival to hospital discharge. Conclusions: In adults with severe TBI, prehospital rapid sequence intubation by paramedics increases the rate of favorable neurologic outcome at 6 months compared with intubation in the hospital.

Relative hyperlactatemia and hospital mortality in critically ill patients: a retrospective multi-centre study

IntroductionHigher lactate concentrations within the normal reference range (relative hyperlactatemia) are not considered clinically significant. We tested the hypothesis that relative hyperlactatemia is independently associated with an increased risk of hospital death.MethodsThis observational study examined a prospectively obtained intensive care database of 7,155 consecutive critically ill patients admitted to the Intensive Care Units (ICUs) of four Australian university hospitals. We assessed the relationship between ICU admission lactate, maximal lactate and time-weighted lactate levels and hospital outcome in all patients and also in those patients whose lactate concentrations (admission n = 3,964, maximal n = 2,511, and time-weighted n = 4,584) were under 2 mmol.L-1 (i.e. relative hyperlactatemia).ResultsWe obtained 172,723 lactate measurements. Higher admission and time-weightedlactate concentration within the reference range was independently associated with increased hospital mortality (admission odds ratio (OR) 2.1, 95% confidence interval (CI) 1.3 to 3.5, P = 0.01; time-weighted OR 3.7, 95% CI 1.9 to 7.00, P < 0.0001). This significant association was first detectable at lactate concentrations > 0.75 mmol.L-1. Furthermore, in patients whose lactate ever exceeded 2 mmol.L-1, higher time-weighted lactate remained strongly associated with higher hospital mortality (OR 4.8, 95% CI 1.8 to 12.4, P < 0.001).ConclusionsIn critically ill patients, relative hyperlactataemia is independently associated with increased hospital mortality. Blood lactate concentrations > 0.75 mmol.L-1 can be used by clinicians to identify patients at higher risk of death. The current reference range for lactate in the critically ill may need to be re-assessed.

A multicenter randomized trial of atorvastatin therapy in intensive care patients with severe sepsis

RATIONALE Observational studies link statin therapy with improved outcomes in patients with severe sepsis. OBJECTIVES To test whether atorvastatin therapy affects biologic and clinical outcomes in critically ill patients with severe sepsis. METHODS Phase II, multicenter, prospective, randomized, double-blind, placebo-controlled trial stratified by site and prior statin use. A cohort of 250 critically ill patients (123 statins, 127 placebo) with severe sepsis were administrated either atorvastatin (20 mg daily) or matched placebo. MEASUREMENTS AND MAIN RESULTS There was no difference in IL-6 concentrations (primary end point) between the atorvastatin and placebo groups (P = 0.76) and no interaction between treatment group and time to suggest that the groups behaved differently over time (P = 0.26). Baseline plasma IL-6 was lower among previous statin users (129 [87-191] vs. 244 [187-317] pg/ml; P = 0.01). There was no difference in length of stay, change in Sequential Organ Failure Assessment scores or mortality at intensive care unit discharge, hospital discharge, 28- or 90-day (15% vs. 19%), or adverse effects between the two groups. Cholesterol was lower in patients treated with atorvastatin (2.4 [0.07] vs. 2.6 [0.06] mmol/L; P = 0.006). In the predefined group of 77 prior statin users, those randomized to placebo had a greater 28-day mortality (28% vs. 5%; P = 0.01) compared with those who received atorvastatin. The difference was not statistically significant at 90 days (28% vs. 11%; P = 0.06). CONCLUSIONS Atorvastatin therapy in severe sepsis did not affect IL-6 levels. Prior statin use was associated with a lower baseline IL-6 concentration and continuation of atorvastatin in this cohort was associated with improved survival. Clinical trial registered with the Australian New Zealand Clinical Trials Registry (ACTRN 12607000028404).

A multicenter, randomized controlled trial comparing early nasojejunal with nasogastric nutrition in critical illness*

Objective: Current guidelines recommend enteral nutrition in critically ill adults; however, poor gastric motility often prevents nutritional targets being met. We hypothesized that early nasojejunal nutrition would improve the delivery of enteral nutrition. Design: Prospective, randomized, controlled trial. Setting: Seventeen multidisciplinary, closed, medical/surgical, intensive care units in Australia. Patients: One hundred and eighty-one mechanically ventilated adults who had elevated gastric residual volumes within 72 hrs of intensive care unit admission. Interventions: Patients were randomly assigned to receive early nasojejunal nutrition delivered via a spontaneously migrating frictional nasojejunal tube, or to continued nasogastric nutrition. Measurements and Main Results: The primary outcome was the proportion of the standardized estimated energy requirement that was delivered as enteral nutrition. Secondary outcomes included incidence of ventilator-associated pneumonia, gastrointestinal hemorrhage, and in-hospital mortality rate. There were 92 patients assigned to early nasojejunal nutrition and 89 to continued nasogastric nutrition. Baseline characteristics were similar. Nasojejunal tube placement into the small bowel was confirmed in 79 (87%) early nasojejunal nutrition patients after a median of 15 (interquartile range 7–32) hrs. The proportion of targeted energy delivered from enteral nutrition was 72% for the early nasojejunal nutrition and 71% for the nasogastric nutrition group (mean difference 1%, 95% confidence interval −3% to 5%, p = .66). Rates of ventilator-associated pneumonia (20% vs. 21%, p = .94), vomiting, witnessed aspiration, diarrhea, and mortality were similar. Minor, but not major, gastrointestinal hemorrhage was more common in the early nasojejunal nutrition group (12 [13%] vs. 3 [3%], p = .02). Conclusions: In mechanically ventilated patients with mildly elevated gastric residual volumes and already receiving nasogastric nutrition, early nasojejunal nutrition did not increase energy delivery and did not appear to reduce the frequency of pneumonia. The rate of minor gastrointestinal hemorrhage was increased. Routine placement of a nasojejunal tube in such patients is not recommended.

Measuring functional and quality of life outcomes following major head injury: Common scales and checklists

Traumatic brain injury (TBI) is a major public health issue, which results in significant mortality and long term disability. The profound impact of TBI is not only felt by the individuals who suffer the injury but also their care-givers and society as a whole. Clinicians and researchers require reliable and valid measures of long term outcome not only to truly quantify the burden of TBI and the scale of functional impairment in survivors, but also to allow early appropriate allocation of rehabilitation supports. In addition, clinical trials which aim to improve outcomes in this devastating condition require high quality measures to accurately assess the impact of the interventions being studied. In this article, we review the properties of an ideal measure of outcome in the TBI population. Then, we describe the key components and performance of the measurement tools most commonly used to quantify outcome in clinical studies in TBI. These measurement tools include: the Glasgow Outcome Scale (GOS) and extended Glasgow Outcome Scale (GOSe); Disability Rating Scale (DRS); Functional Independence Measure (FIM); Functional Assessment Measure (FAM); Functional Status Examination (FSE) and the TBI-specific and generic quality of life measures used in TBI patients (SF-36 and SF-12, WHOQOL-BREF, SIP, EQ-5D, EBIQ, and QOLIBRI).