Critical Care Reviews Newsletter
December 14th 2011
Welcome to the first Critical Care Reviews Newsletter. Every week some of the more important research publications in critical care will be highlighted. These studies are added to the News section of the website on a daily basis, as publication occurs.
It is envisaged that this newsletter will be sent on a weekly basis, probably on a Sunday. If you do not wish to receive the newsletter please use the unsubscribe option below. If you would like this newsletter to contain other information please let me know.
Tuesday December 13th 2011
Acute Lung Injury Therapy
Smith and colleagues report the findings of the BALTI-2 study which assesed the impact of intravenous beta-2 agonist therapy on the outcome of acute lung injury. Previously the BALTI study had demonstrated beta-2 agonist therapy decreased EVLW and plateau pressures in ALI. 162 patients were randomly assigned to the salbutamol group and 164 to the placebo group. Recruitment was stopped after the second interim analysis because of safety concerns. Salbutamol increased 28-day mortality (55 [34%] of 161 patients died in the salbutamol group vs 38 (23%) of 163 in the placebo group; risk ratio [RR] 1·47, 95% CI 1·03—2·08). These findings were consistent with the ALTA study, recently completed by the ARDSnet group.
Abstract. Smith. Effect of intravenous β-2 agonist treatment on clinical outcomes in acute respiratory distress syndrome (BALTI-2): a multicentre, randomised controlled trial. Lancet epub ahead of print December 12 2011
Friday December 9th 2011
Is this the future of critical care - extracorporeal organ support whilst a replacement organ is grown?
In today's Lancet Jungebluth and colleagues report a proof-of-concept study detailing the replacement of a cancerous trachea and bronchus with a a stem-cell-seeded bioartificial nanocomposite augmented with growth hormone therapy. The bioartificial nanocomposite had patent anastomoses, lined with a vascularised neomucosa, and was partly covered by nearly healthy epithelium.
Thursday December 8th 2011
From January's edition of Intensive Care Medicine:
An ESICM systematic review examined the benefits and risks of vasopressin or its analog terlipressin for patients with vasodilatory shock. Six studies were considered for the main analysis on mortality in adults. The crude short-term mortality was 206 of 512 (40.2%) in vasopressin/terlipressin-treated patients and 198 of 461 (42.9%) in controls [six trials, risk ratio (RR) = 0.91; 95% confidence interval (CI) 0.79–1.05; P = 0.21; I 2 = 0%].
Lu and colleagues measured sTREM and PCT via fine needle aspiration (FNA) in 30 patients with a clinical suspicion of secondary infection of necrotic pancreatic tissue. The levels of sTREM-1 and PCT in FNA fluid were found to have the closest correlation with the diagnosis of infected necrosis [sTREM-1: area under the receiver operating characteristic curve (AUC) 0.972; 95% confidence interval (95%CI) 0.837–1.000; PCT: AUC 0.903; 95%CI 0.670–0.990, P > 0.05]. A fluid sTREM-1 cutoff value of 285.6 pg/ml had a sensitivity of 94.4% and a specificity of 91.7%. In a multiple logistic regression analysis, an sTREM-1 level of more than 285 pg/ml and a PCT level of more than 2.0 ng/ml in FNA fluid were independent predictors of infected necrosis.
Eastwood and colleagues retrospectively assessed studied the ‘worst’ alveolar-arterial (A-a) gradient during the first 24 h of ICU admission in 152,680 patients receiving mechanical ventilation in 150 participating ICUs between 2000 and 2009. They found an association between hypoxia and increased in-hospital mortality, but not with hyperoxia in the first 24 h in ICU and mortality in ventilated patients. They conclude these findings differ from previous studies and suggest that the impact of early hyperoxia on mortality remains uncertain.
Regional Anticoagulation for RRT
A systematic review including 6 studies and 658 patients, but excluding liver failure patients or those with a high risk of bleeding. The findings were that the circuit life span in the RCA group was significantly longer than that in the control group, with a mean difference of 23.03 h (95% CI 0.45–45.61 h). RCA was able to reduce the risk of bleeding, with a risk ratio of 0.28 (95% CI 0.15–0.50). Metabolic stability (electrolyte and acid–base stabilities) in performing RCA was comparable to that in other anticoagulation modes, and metabolic derangements (hypernatremia, metabolic alkalosis, and hypocalcemia) could be easily controlled without significant clinical consequences. Two studies compared mortality rate between RCA and control groups, with one reported similar mortality rate and the other reported superiority of RCA over the control group (hazards ratio 0.7).
Effect of AKI on Midazolam Metabolism
73 critically ill patients at risk of AKI and admitted to a general intensive care unit were categorised after initial resuscitation to categories R, I and F of the RIFLE criteria or C (controls). Midazolam concentrations (ng mL−1) increased significantly (p = 0.002) as the severity of AKI worsened [control 3.1 (1.4–5.9), risk 4.7 (1.3–10.3), injury 3.9 (2.0–11.1) and failure 6.8 (2.2–113.6)] and were predicted by the duration of AKI (p = 0.000) and γ-glutamyl transferase (p = 0.005) concentrations.
Tuesday December 6th 2011
A numer of interesting studies have been published in December's issue of Chest.
Firstly, in 62 subjects, a single-centre case-controlled comparison of open abdominal decompression (OAD) versus bedside intensivist performed percutaneous catheter decompression (PCD) for abdominal compartment syndrome. PCD and OAD both were effective in significantly decreasing intra-abdominal pressure and peak inspiratory pressure as well as in increasing abdominal perfusion pressure. PCD potentially avoided the need for subsequent OAD in 25 of 31 patients (81%) treated. Successful PCD therapy was associated with fluid drainage of > 1,000 mL or a decrease in IAP of > 9 mm Hg in the first 4 h postdecompression.
In a multi-centre registry study Kwok and colleagues from ANZICS evaluated the omission of early thromboembolism prophylaxis to 175,665 critically ill adult patients admitted to 134 ICUs in Australia and New Zealand between 2006 and 2010. The crude ICU and hospital mortality in patients who did not receive thromboprophylaxis within 24 h of ICU admission was higher than those who were treated with early thromboprophylaxis (7.6% vs 6.3%, P = .001; 11.2% vs 10.6%, P = .003, respectively). The association between omission of early thromboprophylaxis and hospital mortality remained significant after adjusting for other covariates (OR, 1.22; 95% CI, 1.15-1.30; P = .001). The estimated attributable mortality effect of omitting early thromboprophylaxis for patients with multiple trauma, sepsis, cardiac arrest, and preexisting metastatic cancer was 3.9% (95% CI, 2.2-5.6), 8.0% (95% CI, 5.6-10.4), 15.4% (95% CI, 11.1-19.8), and 9.4% (95% CI, 6.4-12.4), respectively.
The latest meta-analysis evaluating the impact of timing of tracheostomy in critically ill mechaincally ventilated patients. Seven trials with 1,044 patients were analyzed. Early tracheostomy (within 7 days) did not significantly reduce short-term mortality (relative risk [RR], 0.86; 95% CI, 0.65-1.13), long-term mortality (RR, 0.84; 95% CI, 0.68-1.04), or incidence of ventilator-associated pneumonia (RR, 0.94; 95% CI, 0.77-1.15) in critically ill patients. The timing of the tracheotomy was not associated with a markedly reduced duration of mechanical ventilation (MV) (weighted mean difference [WMD], −3.90 days; 95% CI, −9.71-1.91) or sedation (WMD, −7.09 days; 95% CI, −14.64-0.45), shorter stay in ICU (WMD, −6.93 days; 95% CI, −16.50-2.63) or hospital (WMD, 1.45 days; 95% CI, −5.31-8.22), or more complications (RR, 0.94; 95% CI, 0.66-1.34).
Abstract. Wang. The Timing of Tracheotomy in Critically Ill Patients Undergoing Mechanical Ventilation. A Systematic Review and Meta-analysis of Randomized Controlled Trials. Chest 2011;140(6):1456-1465.
Critical Care Load Epidemiology
1,707 ICU admissions were identified from 1,461 patients in a defined US suburban community with unrestricted access to critical care services. Incidences of critical care syndromes (reported per 100,000 population (95% CIs) and age adjusted to the 2006 US population) were respiratory failure, 430 (390-470); acute kidney injury, 290 (257-323); severe sepsis, 286 (253-319); all-cause shock, 194 (167-221); acute lung injury, 86 (68-105); all-cause coma, 43 (30-55); and overt disseminated intravascular coagulation, 18 (10-26). Incidence of mechanical ventilation was invasive, 310 (276-344); noninvasive, 180 (154-206); vasopressors and inotropes, 183(155-208). Renal replacement therapy incidence was 96 (77-116). Of the cohort, 1,330 patients (91%) survived to hospital discharge. Short- and long-term survival decreased by the number of failing organs.
I hope you find these brief summaries useful.
Until next week