Ian Seppelt

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.

Decompressive Craniectomy in Diffuse Traumatic Brain Injury

BACKGROUND It is unclear whether decompressive craniectomy improves the functional outcome in patients with severe traumatic brain injury and refractory raised intracranial pressure. METHODS From December 2002 through April 2010, we randomly assigned 155 adults with severe diffuse traumatic brain injury and intracranial hypertension that was refractory to first-tier therapies to undergo either bifrontotemporoparietal decompressive craniectomy or standard care. The original primary outcome was an unfavorable outcome (a composite of death, vegetative state, or severe disability), as evaluated on the Extended Glasgow Outcome Scale 6 months after the injury. The final primary outcome was the score on the Extended Glasgow Outcome Scale at 6 months. RESULTS Patients in the craniectomy group, as compared with those in the standard-care group, had less time with intracranial pressures above the treatment threshold (P<0.001), fewer interventions for increased intracranial pressure (P<0.02 for all comparisons), and fewer days in the intensive care unit (ICU) (P<0.001). However, patients undergoing craniectomy had worse scores on the Extended Glasgow Outcome Scale than those receiving standard care (odds ratio for a worse score in the craniectomy group, 1.84; 95% confidence interval [CI], 1.05 to 3.24; P=0.03) and a greater risk of an unfavorable outcome (odds ratio, 2.21; 95% CI, 1.14 to 4.26; P=0.02). Rates of death at 6 months were similar in the craniectomy group (19%) and the standard-care group (18%). CONCLUSIONS In adults with severe diffuse traumatic brain injury and refractory intracranial hypertension, early bifrontotemporoparietal decompressive craniectomy decreased intracranial pressure and the length of stay in the ICU but was associated with more unfavorable outcomes. (Funded by the National Health and Medical Research Council of Australia and others; DECRA Australian Clinical Trials Registry number, ACTRN012605000009617.).

Use of corticosteroids in acute lung injury and acute respiratory distress syndrome: A systematic review and meta-analysis*

Objective:Controversy remains as to whether low-dose corticosteroids can reduce the mortality and morbidity of acute lung injury (ALI) or the acute respiratory distress syndrome (ARDS) without increasing the risk of adverse reactions. We aimed to evaluate all studies investigating prolonged corticosteroids in low-to-moderate dose in ALI or ARDS. Data Sources:MEDLINE, EMBASE, Current Content, and Cochrane Central Register of Controlled Trials, and bibliographies of retrieved articles. Study Selection:Randomized controlled trials (RCTs) and observational studies reported in any language that used 0.5–2.5 mg·kg−1·d−1 of methylprednisolone or equivalent to treat ALI/ARDS. Data Extraction:Data were extracted independently by two reviewers and included study design, patient characteristics, interventions, and mortality and morbidity outcomes. Data Synthesis:Both cohort studies (five studies, n = 307) and RCTs (four trials, n = 341) showed a similar trend toward mortality reduction (RCTs relative risk 0.51, 95% CI 0.24–1.09; p = 0.08; cohort studies relative risk 0.66, 95% CI 0.43–1.02; p = 0.06). The overall relative risk was 0.62 (95% CI 0.43–0.91; p = 0.01). There was also improvement in length of ventilation-free days, length of intensive care unit stay, Multiple Organ Dysfunction Syndrome Score, Lung Injury Scores, and improvement in Pao2/Fio2. There was no increase in infection, neuromyopathy, or any major complications. There was significant heterogeneity in the pooled studies. Subgroup and meta-regression analyses showed that heterogeneity had minimal effect on treatment efficacy; however, these findings were limited by the small number of studies used in the analyses. Conclusion:The use of low-dose corticosteroids was associated with improved mortality and morbidity outcomes without increased adverse reactions. The consistency of results in both study designs and all outcomes suggests that they are an effective treatment for ALI or ARDS. The mortality benefits in early ARDS should be confirmed by an adequately powered randomized trial.

Critical Illness Due to 2009 A/H1N1 Influenza in Pregnant and Postpartum Women: Population Based Cohort Study

Objective To describe the epidemiology of 2009 A/H1N1 influenza in critically ill pregnant women. Design Population based cohort study. Setting All intensive care units in Australia and New Zealand. Participants All women with 2009 H1N1 influenza who were pregnant or recently post partum and admitted to an intensive care unit in Australia or New Zealand between 1 June and 31 August 2009. Main outcome measures Maternal and neonatal mortality and morbidity. Results 64 pregnant or postpartum women admitted to an intensive care unit had confirmed 2009 H1N1 influenza. Compared with non-pregnant women of childbearing age, pregnant or postpartum women with 2009 H1N1 influenza were at increased risk of admission to an intensive care unit (relative risk 7.4, 95% confidence interval 5.5 to 10.0). This risk was 13-fold greater (13.2, 9.6 to 18.3) for women at 20 or more weeks’ gestation. At the time of admission to an intensive care unit, 22 women (34%) were post partum and two had miscarried. 14 women (22%) gave birth during their stay in intensive care and 26 (41%) were discharged from an intensive care unit with ongoing pregnancy. All subsequently delivered. 44 women (69%) were mechanically ventilated. Of these, nine (14%) were treated with extracorporeal membrane oxygenation. Seven women (11%) died. Of 60 births after 20 weeks’ gestation, four were stillbirths and three were infant deaths. 22 (39%) of the liveborn babies were preterm and 32 (57%) were admitted to a neonatal intensive care unit. Of 20 babies tested, two were positive for the 2009 H1N1 virus. Conclusions Pregnancy is a risk factor for critical illness related to 2009 H1N1 influenza, which causes maternal and neonatal morbidity and mortality.

Prognostic values of B-type natriuretic peptide in severe sepsis and septic shock.

Objective:To investigate the changes in B-type natriuretic peptide concentrations in patients with severe sepsis and septic shock and to investigate the value of B-type natriuretic peptide in predicting intensive care unit outcomes. Design:Prospective observational study. Setting:General intensive care unit. Patients:Forty patients with severe sepsis or septic shock. Interventions:None. Measurements and Main Results:B-type natriuretic peptide measurements and echocardiography were carried out daily for 10 consecutive days. In-hospital mortality and length of stay were recorded. The admission B-type natriuretic peptide concentrations were generally increased (747 ± 860 pg/mL). B-type natriuretic peptide levels were elevated in patients with normal left ventricular systolic function (568 ± 811 pg/mL), with sepsis-related reversible cardiac dysfunction (630 ± 726 pg/mL), and with chronic cardiac dysfunction (1311 ± 1097 pg/mL). There were no significance changes in B-type natriuretic peptide levels over the 10-day period. The daily B-type natriuretic peptide concentrations for the first 3 days neither predicted in-hospital mortality nor correlated with length of intensive care unit or hospital stay. Conclusion:B-type natriuretic peptide concentrations were increased in patients with severe sepsis or septic shock regardless of the presence or absence of cardiac dysfunction. Neither the B-type natriuretic peptide levels for the first 3 days nor the daily changes in B-type natriuretic peptide provided prognostic value for in-hospital mortality and length of stay in this mixed group of patients, which included patients with chronic cardiac dysfunction.

The impact of bacterial and viral co-infection in severe influenza

Please cite this paper as: Blyth et al. (2013) The impact of bacterial and viral co‐infection in severe influenza. Influenza and Other Respiratory Viruses 7(2) 168–176.

Early goal-directed sedation versus standard sedation in mechanically ventilated critically ill patients: a pilot study*.

Objective:To assess the feasibility and safety of delivering early goal-directed sedation compared with standard sedation. Design:Pilot prospective, multicenter, randomized, controlled trial. Setting:Six ICUs. Patients:Critically ill adults mechanically ventilated for greater than 24 hours. Interventions:Patients randomized to early goal-directed sedation received a dexmedetomidine-based algorithm targeted to light sedation (Richmond Agitation Sedation Score of –2 to 1). Patients randomized to standard sedation received propofol and/or midazolam-based sedation as clinically appropriate. Measurements and Main Results:The main feasibility outcomes were time to randomization and proportion of Richmond Agitation Sedation Score assessments in the first 48 hours in the light and deep sedation range. Safety outcomes were delirium-free days, vasopressor and physical restraints use, and device removal. Randomization occurred within a median (interquartile range) of 1.1 hours (0.46–1.9) after intubation or ICU admission for out of ICU intubation. Patients in the early goal-directed sedation (n = 21) mean (SD) Acute Physiology and Chronic Health Evaluation II score was 20.2 (6.2) versus 18.6 (8.8; p = 0.53) in the standard sedation (n = 16). A significantly higher proportion of patients was lightly sedated on days 1, 2, and 3 (12/19 [63.2%], 19/21 [90.5%], and 18/20 [90%] vs 2/14 [14.3%], 8/15 [53.3%], and 9/15 [60%]; p = 0.005, 0.011, 0.036) and more Richmond Agitation Sedation Scale assessments between (–2 and 1), in the first 48 hours (203/307 [66%] versus (74/197 [38%]; p = 0.01) in the early goal-directed sedation versus standard sedation, respectively. Early goal-directed sedation patients received midazolam on 6 of 173 (3.5%) versus 4 of 114 (3.5%) standard sedation patient-days when dexmedetomidine was given. Propofol was given to 16 of 21 (76%) of early goal-directed sedation versus 16 of 16 (100%) of standard sedation patients (p = 0.04). Early goal-directed sedation patients had 101 of 175 (58%) versus 54 of 114 (47%; p = 0.27) delirium-free days and required significantly less physical restraints 1 (5%) versus 5 (31%; p = 0.03) than standard sedation patients. There were no differences in vasopressor use and self-extubation. Conclusions:Delivery of early goal-directed sedation was feasible, appeared safe, achieved early light sedation, minimized benzodiazepines and propofol, and decreased the need for physical restraints. The findings of this pilot study justify further investigation of early goal-directed sedation.

Pro/Con debate: is procalcitonin useful for guiding antibiotic decision making in critically ill patients?

You are concerned about the escalating use of antibiotics in your intensive care unit (ICU). This has put a strain on the ICU budget and is possibly resulting in the emergence of resistant bacteria. You review the situation with your team and one suggestion is to consider using biomarkers such as procalcitonin to better guide appropriate antibiotic decision making.

Traditional landmark versus ultrasound guided tracheal puncture during percutaneous dilatational tracheostomy in adult intensive care patients: a randomised controlled trial

IntroductionLong-term ventilated intensive care patients frequently require tracheostomy. Although overall risks are low, serious immediate and late complications still arise. Real-time ultrasound guidance has been proposed to decrease complications and improve the accuracy of the tracheal puncture. We aimed to compare the procedural safety and efficacy of real-time ultrasound guidance with the traditional landmark approach during percutaneous dilatational tracheostomy (PDT).MethodsA total of 50 patients undergoing PDT for clinical indications were randomly assigned, after obtaining informed consent, to have the tracheal puncture procedure carried out using either traditional anatomical landmarks or real-time ultrasound guidance. Puncture position was recorded via bronchoscopy. Blinded assessors determined in a standardised fashion the deviation of the puncture off midline and whether appropriate longitudinal position between the first and fourth tracheal rings was achieved. Procedural safety and efficacy data, including complications and number of puncture attempts required, were collected.ResultsIn total, 47 data sets were evaluable. Real-time ultrasound guidance resulted in significantly more accurate tracheal puncture. Mean deviation from midline was 15 ± 3° versus 35 ± 5° (P = 0.001). The proportion of appropriate punctures, defined a priori as 0 ± 30° from midline, was significantly higher: 20 (87%) of 23 versus 12 (50%) of 24 (RR = 1.74; 95% CI = 1.13 to 2.67; P = 0.006). First-pass success rate was 20 (87%) of 23 in the ultrasound group and 14 (58%) of 24 in the landmark group (RR = 1.49; 95% CI = 1.03 to 2.17; P = 0.028). The observed decrease in procedural complications was not statistically significant: 5 (22%) of 23 in the ultrasound group versus 9 (37%) of 24 in the landmark group (RR = 0.58; 95% CI = 0.23 to 1.47; P = 0.24).ConclusionsUltrasound guidance significantly improved the rate of first-pass puncture and puncture accuracy. Fewer procedural complications were observed; however, this did not reach statistical significance. These results support wider general use of real-time ultrasound guidance as an additional tool to improve PDT.Trial registrationAustralian New Zealand Clinical Trials Registry ID: ACTRN12611000237987 (registered 4 March 2011)

Critical illness with AH1N1v influenza in pregnancy: a comparison of two population‐based cohorts

Please cite this paper as: Knight M, Pierce M, Seppelt I, Kurinczuk J, Spark P, Brocklehurst P, McLintock C, Sullivan E, on behalf of the UK’s Obstetric Surveillance System, the ANZIC Influenza Investigators, and the Australasian Maternity Outcomes Surveillance System. Critical illness with AH1N1v influenza in pregnancy: a comparison of two population‐based cohorts. BJOG 2011;118:232–239.