July 29th 2012
Welcome to the 34th Critical Care Reviews Newsletter. Every week over three hundred clinical and scientific journals are monitored and the most important and interesting research publications in critical care are highlighted. These studies are added to the Current Articles section of the website on a daily basis, as publication occurs. A link to either the full text or abstract, depending on the publishers degree of open access, is attached. Also, links to other important papers, such as guidelines or consensus statements are included. Free review articles from across the medical literature are also highlighted.
There are several very interesting research articles published this week, including new systematic reviews on steroids in septic shock and neuromuscular blockers in ARDS, plus papers on acute renal failure. The new free review papers published this week are as diverse as ever, from Dengue fever to medical errors. The full text of the new ESC guidelines on the management of acute and chronic heart failure is also linked to.
Following on from last weeks addition of social media to the site, I've opened a twitter account @critcarereviews. If you would like instant updates on new papers being added to site, these will be tweeted as soon as the links have been made. A "follow us on twitter" button has also been added.
Anaesthesia & Analgesia: Nitrous Oxide
In a single centre study to evaluate the safety of nitrous oxide anaesthesia, Turan investigated 49,016 patients who had noncardiac surgery. Of 37,609 qualifying patients, 16,961 were given N2O (45%) and 20,648 were not (55%). 10,755 nitrous patients were propensity score-matched with 10,755 nonnitrous patients. The use of inhaled N2O intraoperatively was associated with reduced 30-day mortality (OR: 97.5% CI, 0.67, 0.46–0.97; P = 0.02) and 17% reduced odds (OR: 0.83, 0.74–0.92) of major in-hospital morbidity/mortality in comparison with nonnitrous use (P < 0.001). N2O use was only associated with reduced odds of respiratory morbidities (OR, 95% Bonferroni-adjusted CI: 0.59, 0.44–0.78).
Anaesthesia & Analgesia: Tranexamic Acid
To evaluate the efficacy of tranexamic acid on postoperative bleeding and transfusion requirements, Wang et al performed a prospective, randomized, double-blind, placebo-controlled study in 231 consectutive patients undergoing off-pump coronary artery bypass grafting. Patients received either tranexamic acid (bolus 1 g before surgical incision followed by an infusion of 400 mg/h during surgery; n = 116) or a placebo (infusion equivalent volume of saline solution; n = 115). Those receiving tranexamic acid had reduced chest tube drainage at 6 hours (270 ± 118 mL vs 416 ± 179 mL, P < 0.001) and 24 hours (654 ± 224 mL vs 891 ± 295 mL, P < 0.001), as well as reduced allogeneic red blood cell transfusions (47 vs 31.9%, P = 0.019) and fresh frozen plasma (29.6% vs 17.2%, P = 0.027) transfusions. Neither morbidity nor mortality differed between treatments.
American Academy of Emergency Medicine: Steroids in Septic Shock
The Sepsis Sub-committee of the American Academy of Emergency Medicine Clinical Practice Committee performed a systematic review, identifying 7 studies investigating the efficacy of low-dose corticosteroids in septic shock, 6 of which reported mortality. Although low-dose steroid therapy was associated with greater reversal of shock (RR 1.17; 95% CI 1.07–1.28), there was no improvement in 28 day mortality (RR 0.92; 95% CI 0.79–1.07).
Abstract: Sherwin. Do low-dose corticosteroids improve mortality or shock reversal in patients with septic shock? A systematic review and position statement prepared for the American Academy of Emergency Medicine. JEM 2012;43:7-12
Annals of Intensive Care: Neuromuscular Blockade in ARDS
Neto et al performed a systematic review and meta analysis of studies investigating neuromuscular blockade versus non-neuromuscular blockade in the management of ARDS. Three studies totalling 431 subjects were identified. Neuromuscular blockade was associated with significant improvements, with reduced mortality (risk ratio, 0.71; 95 % CI: 0.55 - 0.90;), improved ventilator free days at day 28 (p = 0.020), higher PaO2/FiO2 ratios (p = 0.004), and less barotraumas (p = 0.030). There was no difference in the incidence of critical illness neuromyopathy (p = 0.540).
Full Text: Neto. Neuromuscular blocking agents in patients with acute respiratory distress syndrome: a summary of the current evidence from three randomized controlled trials. Annals of Intensive Care 2012,2:33
American Journal of respiratory and Critical Care Medicine: Long-Term Outcome
Lone and Walsh performed an observation study in 10 Scottish ICUs (n=872) evaluating the long term association between organ failure and outcome. 58% had died by 5 years, with 34.4% of deaths occuring within 28 days. Circulatory (OR 2.5; 95% CI 1.8-3.7), liver (OR 2.3; 1.1-5.0) and respiratory failure (OR 2.1; 1.3-3.5) were independently associated with five-year mortality. 81% of patients in the highest organ failure burden tertile died during follow-up, with an OR 6.3 relative to lowest tertile; p<0.001. Patients with higher organ failure burden who were still alive at 1 year were more likely to subsequently die than patients with lower organ failure burden (OR 2.4, p=0.02; highest versus lowest tertile).
To validate the classification of hypovolaemic shock given by the Advanced Trauma Life Support (ATLS), Mutschler et al performed an analysis of 36 504 patients in the TraumaRegister DGU® database evaluating the relationship between the 4 ATLS categories of hypotension and their associated heart rate, blood pressure and Glasgow Coma Scale ranges. Only 3 411 patients (9.3%) could be adequately classified according to ATLS, whereas 33 093 did not match the combination of all three criteria given by ATLS.
Clinical Kidney Journal: Renal Replacement Therapy Outcomes
Sciffl et al performed a single-centre prospective observational study of 425 consecutive critically ill patients, with previously normal renal function, who acquired AKI requiring RRT. In-hospital mortality was 47%, with 1, 5 and 10 years mortality rates of 65, 75 and 80%, respectively. At hospital discharge, recovery of renal function was complete in 56% of survivors, none of whom subsequently developed renal impairment. 90 of 100 survivors with partial recovery of renal function had ongoing chronic kidney disease, with 12 progressing to end-stage renal disease (3% of the cohort or 5% of survivors). These patients had increased rates of hypertension, fatal cardiac diseases and all-cause death rate.
Critical Care: SLED-BD
In a single-centre study Schwenger et al randomized 232 AKI patients who underwent renal replacement therapy to either 12-h sustained low efficiency dialysis using a single-pass batch dialysis system (SLED-BD, n=115) or to 24-h predilutional continuous veno-venous hemofiltration (CVVH, n=117), with both therapies using a blood flow of 100-120 ml/min. There was no difference in the primary outcome measure of 90-day mortality, (SLED: 49.6% vs. CVVH: 55.6%, P=0.43) or in haemodynamic stability. SLED-BD was superior in terms of fewer days of mechanical ventilation (17.7 +/- 19.4 vs. 20.9 +/- 19.8, P=0.047), reduced ICU length of stay (19.6 +/- 20.1 vs. 23.7 +/- 21.9, P=0.04), reduced blood transfusions (1,375 +/- 2,573 ml vs. 1,976 +/- 3,316 ml, P=0.02) and reduced nursing time spent for renal replacement therapy (P<0.001) resulting in lower costs.
Full Text: Schwenger. Sustained low efficiency dialysis using a single-pass batch system in acute kidney injury - a randomized interventional trial: the REnal Replacement Therapy Study in Intensive Care Unit PatiEnts. Critical Care 2012, 16:R140
European Journal of Heart Failure: Heart Failure
Full Text: McMurray. ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure 2012: The Task Force for the Diagnosis and Treatment of Acute and Chronic Heart Failure 2012 of the European Society of Cardiology. Developed in collaboration with the Heart Failure Association (HFA) of the ESC. Eur J Heart Fail 2012;14:803-869
Review - Clinical
Circulation: Periprocedureal Anticoagulation
Infection and Drug Resistance: Dengue Fever
Avicenna Journal of Medicine: Mobile Anaesthesia
Lung India: Tuberculosis
Review - Basic Science
Nature Biotechnology: Tissue Engineering
In another first for tissue engineering, in a proof of concept study, a team from America generated a freely swimming jellyfish from chemically dissociated rat tissue and silicone polymer. The authors speculate this strategy of reverse engineering would be broadly applicable to produce new muscular organs. How long before transplatation medicine moves from organ donation to either organ regeneration or de novo organogenesis?
Review - Non-Clinical
Medicolegal and Bioethics: Medical Errors
- Hannawa. Principles of medical ethics: implications for the disclosure of medical errors. Medicolegal and Bioethics 2012;2012(2):1-11
- Kels. The spectrum of medical errors: when patients sue. International Journal of General Medicine 2012;2012;5:613–619
I hope you find these brief summaries useful.
Until next week