The effect of mild induced hypothermia on outcomes of patients after cardiac arrest: a systematic review and meta-analysis of randomised controlled trials

The effect of mild induced hypothermia on outcomes of patients after cardiac arrest: a systematic review and meta-analysis of randomised controlled trials
 Zhang XW et al.
Critical Care 2015, 19:417

Introduction: Mild induced hypothermia (MIH) is believed to reduce mortality and neurological impairment after out-of-hospital cardiac arrest. However, a recently published trial demonstrated that hypothermia at 33 °C did not confer a benefit compared with that of 36 °C. Thus, a systematic review and meta-analysis of randomised controlled trials (RCTs) was made to investigate the impact of MIH compared to controls on the outcomes of adult patients after cardiac arrest. Methods: We searched the following electronic databases: PubMed/MEDLINE, the Cochrane Library, Embase, the Web of Science, and Elsevier Science (inception to December 2014). RCTs that compared MIH with controls with temperature >34 °C in adult patients after cardiac arrest were retrieved. Two investigators independently selected RCTs and completed an assessment of the quality of the studies. Data were analysed by the methods recommended by the Cochrane Collaboration. Random errors were evaluated with trial sequential analysis.
Results: Six RCTs, including one abstract, were included. The meta-analysis of included trials revealed that MIH did not significantly decrease the mortality at hospital discharge (risk ratio (RR) = 0.92; 95 % confidence interval (CI), 0.82–1.04; p = 0.17) or at 6 months or 180 days (RR = 0.94; 95 % CI, 0.73–1.21; p = 0.64), but it did reduce the mortality of patients with shockable rhythms at hospital discharge (RR = 0.74; 95 % CI, 0.59–0.92; p = 0.008) and at 6 months or 180 days. However, MIH can improve the outcome of neurological function at hospital discharge (RR = 0.80; 95 % CI, 0.64–0.98; p = 0.04) especially in those patients with shockable rhythm but not at 6 months or 180 days. Moreover, the incidence of complications in the MIH group was significantly higher than that in the control group. Finally, trial sequential analysis indicated lack of firm evidence for a beneficial effect.
Conclusion: The available RCTs suggest that MIH does not appear to improve the mortality of patients with cardiac arrest while it may have a beneficial effect for patients with shockable rhythms. Although MIH may result in some adverse events, it helped lead to better outcomes regarding neurological function at hospital discharge. Large-scale ongoing trials may provide data better applicable to clinical practice.

The experiences of nurses implementing the Modified Early Warning Score and a 24-hour on-call Mobile Intensive Care Nurse: An exploratory study

The experiences of nurses implementing the Modified Early Warning Score and a 24-hour on-call Mobile Intensive Care Nurse: An exploratory study
Stafseth K S et al.
Article in Press


Aims and objectives: To explore experiences of nurses implementing and using the Modified Early Warning Score (MEWS) and a Mobile Intensive Care Nurse (MICN) providing 24-hour on-call nursing support.
Background: To secure patient safety in hospital wards, nurses may increase the quality of care using a tool to detect the failure of vital functions. Possibilities for support can be provided through on-call supervision from a qualified team or nurse.
Design: This exploratory qualitative investigation used focus group interviews with nurses from two wards of a university hospital in Norway.
Methods: A purposive sample of seven registered nurses was interviewed in focus groups. A semi-structured guide and an inductive thematic analysis were used to identify interview themes.
Results: Three themes emerged: (1) experiences with the early recognition of deterioration using the MEWS, (2) supportive collaboration and knowledge transfer between nurses and (3) a “new” precise language using the score for communicating with physicians. The use of scores and support were perceived as improving care for deteriorating patients and for supporting the collaboration of nurses with other professionals.
Conclusion: In our study, nurses described increased confidence in the recognition of deteriorating patients and in the management of such situations. The non-critical attitude, supportive communication and interactive learning according to the MICN were essential elements for success.

A Multicenter Evaluation of Prolonged Empiric Antibiotic Therapy in Adult ICUs in the United States

A Multicenter Evaluation of Prolonged Empiric Antibiotic Therapy in Adult ICUs in the United States
Thomas, Z et al.
Critical Care Medicine: December 2015 - Volume 43 - Issue 12 - p 2527–2534


Objective: The purpose of this study is to determine the rate of prolonged empiric antibiotic therapy in adult ICUs in the United States. Our secondary objective is to examine the relationship between the prolonged empiric antibiotic therapy rate and certain ICU characteristics. Design: Multicenter, prospective, observational, 72-hour snapshot study. Setting: Sixty-seven ICUs from 32 hospitals in the United States. Patients: Nine hundred ninety-eight patients admitted to the ICU between midnight on June 20, 2011, and June 21, 2011, were included in the study. Intervention: None.
Measurements and Main Results: Antibiotic orders were categorized as prophylactic, definitive, empiric, or prolonged empiric antibiotic therapy. Prolonged empiric antibiotic therapy was defined as empiric antibiotics that continued for at least 72 hours in the absence of adjudicated infection. Standard definitions from the Centers for Disease Control and Prevention were used to determine infection. Prolonged empiric antibiotic therapy rate was determined as the ratio of the total number of empiric antibiotics continued for at least 72 hours divided by the total number of empiric antibiotics. Univariate analysis of factors associated with the ICU prolonged empiric antibiotic therapy rate was conducted using Student t test. A total of 660 unique antibiotics were prescribed as empiric therapy to 364 patients. Of the empiric antibiotics, 333 of 660 (50%) were continued for at least 72 hours in instances where Centers for Disease Control and Prevention infection criteria were not met. Suspected pneumonia accounted for approximately 60% of empiric antibiotic use. The most frequently prescribed empiric antibiotics were vancomycin and piperacillin/tazobactam. ICUs that utilized invasive techniques for the diagnosis of ventilator-associated pneumonia had lower rates of prolonged empiric antibiotic therapy than those that did not, 45.1% versus 59.5% (p = 0.03). No other institutional factor was significantly associated with prolonged empiric antibiotic therapy rate.
Conclusions: Half of all empiric antibiotics ordered in critically ill patients are continued for at least 72 hours in absence of adjudicated infection. Additional studies are needed to confirm these findings and determine the risks and benefits of prolonged empiric therapy in the critically ill.

Nutritional Status and Mortality in the Critically Ill

Nutritional Status and Mortality in the Critically Ill
Mogensen, K et al
December 2015 - Volume 43 - Issue 12


Objectives: The association between nutritional status and mortality in critically ill patients is unclear based on the current literature. To clarify this relation, we analyzed the association between nutrition and mortality in a large population of critically ill patients and hypothesized that mortality would be impacted by nutritional status. Design: Retrospective observational study.
Setting: Single academic medical center. Patients: Six thousand five hundred eighteen adults treated in medical and surgical ICUs between 2004 and 2011. Interventions: None. Measurements and Main Results: All cohort patients received a formal, in-person, standardized evaluation by a registered dietitian. The exposure of interest, malnutrition, was categorized as nonspecific malnutrition, protein-energy malnutrition, or well nourished and determined by data related to anthropometric measurements, biochemical indicators, clinical signs of malnutrition, malnutrition risk factors, and metabolic stress. The primary outcome was all-cause 30-day mortality determined by the Social Security Death Master File. Associations between nutrition groups and mortality were estimated by bivariable and multivariable logistic regression models. Adjusted odds ratios were estimated with inclusion of covariate terms thought to plausibly interact with both nutrition status and mortality. We used propensity score matching on baseline characteristics to reduce residual confounding of the nutrition status category assignment. In the cohort, nonspecific malnutrition was present in 56%, protein-energy malnutrition was present in 12%, and 32% were well nourished. The 30-day and 90-day mortality rates for the cohort were 19.1% and 26.6%, respectively. Nutritional status is a significant predictor of 30-day mortality following adjustment for age, gender, race, medical versus surgical patient type, Deyo-Charlson index, acute organ failure, vasopressor use, and sepsis: nonspecific malnutrition 30-day mortality odds ratio, 1.17 (95% CI, 1.01–1.37); protein-energy malnutrition 30-day mortality odds ratio, 2.10 (95% CI, 1.70–2.59), all relative to patients without malnutrition. In the matched cohort, the adjusted odds of 30-day mortality in the group of propensity score-matched patients with protein-energy malnutrition was two-fold greater than that of patients without malnutrition. Conclusion: In a large population of critically ill adults, an association exists between nutrition status and mortality.

What is the right temperature to cool post-cardiac arrest patients?

What is the right temperature to cool post-cardiac arrest patients?
Chandrasekaran PN et al.
Critical Care 2015, 19:406


Background: Brain ischemia and reperfusion injury leading to tissue degeneration and loss of neurological function following return of spontaneous circulation after cardiac arrest (CA) is a well-known entity. Two landmark trials in 2002 showed improved survival and neurological outcome of comatose survivors of out-of-hospital cardiac arrest (OHCA) of presumed cardiac origin when the patients were subjected to therapeutic hypothermia of 32 to 34 °C for 12 to 24 hours. However, the optimal target temperature for these cohorts is yet to be established and also it is not clear whether strict fever management and maintaining near normal body temperature are alone sufficient to improve the outcome.
Methods: Objective: The objective is to determine whether a hypothermic goal of a near-normal body temperature of 36 °C reduces all-cause mortality compared with a moderate hypothermia of 33 °C for the unconscious survivors of OHCA of presumed cardiac origin when subjected randomly to these different targeted temperatures.
Design: A multicenter, international, open label, randomized controlled trial. Setting: Thirty-six ICUs in Europe and Australia participated in this study.Participants: Unconscious adults (older than 18 years of age) who survived (Glasgow coma scale less than 8) OHCA due to presumed cardiac origin with subsequent persistent return of spontaneous circulation (more than 20 minutes without chest compressions).
Intervention: The above participant cohorts were randomized to targeted body temperature of either 33 °C or 36 °C for 36 hours after the CA with gradual rewarming of both groups to 37 °C (hourly increments of 0.5 °C) after the initial 28 hours. Body temperatures in both the groups were then maintained below 37.5 °C for 72 hours after the initial 36 hours.
Outcomes: Primary outcome measure of all-cause mortality in both the groups at the end of the trial with the secondary outcome measure of all-cause mortality, composite neurological function as evaluated by cerebral performance category scale and modified ranking scale at the end of 180 days were studied.
Results: Out of the 939 participants, all-cause mortality at the end of the trial was 50 % in the 33 °C group (225 of 466 patients) compared with 48 % in the 36 °C group (235 of 473 patients); the hazard ratio with a temperature of 33 °C was 1.06 (95 % confidence interval (CI) 0.89 to 1.28, P = 0.51). At the end of 180 days, 54 % of patients in the 33 °C group versus 52 % in the 36 °C group had died or had poor neurological outcome according to cerebral performance category (risk ratio 1.02, 95 % CI 0.88 to 1.16, P = 0.78) but the modified ranking scale at the end of 180 days was unchanged (52 %) in both groups (risk ratio 1.01, 95 % CI 0.89 to 1.14, P = 0.87).
Conclusions: Maintaining targeted lower normothermia of 36 °C had similar outcomes compared with induced moderate hypothermia of 33 °C for unconscious survivors of OHCA of presumed cardiac cause.

Impact of antibacterials on subsequent resistance and clinical outcomes in adult patients with viral pneumonia: an opportunity for stewardship

Impact of antibacterials on subsequent resistance and clinical outcomes in adult patients with viral pneumonia: an opportunity for stewardship
Crotty MP et al.
Critical Care 2015, 19:404


Introduction: Respiratory viruses are increasingly recognized as significant etiologies of pneumonia among hospitalized patients. Advanced technologies using multiplex molecular assays and polymerase-chain reaction increase the ability to identify viral pathogens and may ultimately impact antibacterial use.
Method: This was a single-center retrospective cohort study to evaluate the impact of antibacterials in viral pneumonia on clinical outcomes and subsequent multidrug-resistant organism (MDRO) infections/colonization. Patients admitted from March 2013 to November 2014 with positive respiratory viral panels (RVP) and radiographic findings of pneumonia were included. Patients transferred from an outside hospital or not still hospitalized 72 hours after the RVP report date were excluded. Patients were categorized based on exposure to systemic antibacterials: less than 3 days representing short-course therapy and 3 to 10 days being long-course therapy.
Results: A total of 174 patients (long-course, n = 67; short-course, n = 28; mixed bacterial-viral infection, n = 79) were included with most being immunocompromised (56.3 %) with active malignancy the primary etiology (69.4 %). Rhinovirus/Enterovirus (23 %), Influenza (19 %), and Parainfluenza (15.5 %) were the viruses most commonly identified. A total of 13 different systemic antibacterials were used as empiric therapy in the 95 patients with pure viral infection for a total of 466 days-of-therapy. Vancomycin (50.7 %), cefepime (40.3 %), azithromycin (40.3 %), meropenem (23.9 %), and linezolid (20.9 %) were most frequently used. In-hospital mortality did not differ between patients with viral pneumonia in the short-course and long-course groups. Subsequent infection/colonization with a MDRO was more frequent in the long-course group compared to the short-course group (53.2 vs 21.1 %; P = 0.027).
Conclusion: This study found that long-course antibacterial use in the setting of viral pneumonia had no impact on clinical outcomes but increased the incidence of subsequent MDRO infection/colonization.

Safety and Efficacy of Combined Extracorporeal CO2 Removal and Renal Replacement Therapy in Patients With Acute Respiratory Distress Syndrome and Acute Kidney Injury: The Pulmonary and Renal Support in Acute Respiratory Distress Syndrome Study

Safetyand Efficacy of Combined Extracorporeal CO2 Removal and Renal Replacement Therapy in Patients With Acute Respiratory Distress Syndrome and Acute Kidney Injury: The Pulmonary and Renal Support in Acute Respiratory Distress Syndrome Study
Allardet-Servent, J et al.
Critical Care Medicine: December 2015 - Volume 43 - Issue 12 - p 2570–2581


Objective: To assess the safety and efficacy of combining extracorporeal CO2 removal with continuous renal replacement therapy in patients presenting with acute respiratory distress syndrome and acute kidney injury. Design: Prospective human observational study.
Settings: Patients received volume-controlled mechanical ventilation according to the acute respiratory distress syndrome net protocol. Continuous venovenous hemofiltration therapy was titrated to maintain maximum blood flow and an effluent flow of 45 mL/kg/h with 33% predilution.
Patients: Eleven patients presenting with both acute respiratory distress syndrome and acute kidney injury required renal replacement therapy. Interventions: A membrane oxygenator (0.65 m2) was inserted within the hemofiltration circuit, either upstream (n = 7) or downstream (n = 5) of the hemofilter. Baseline corresponded to tidal volume 6 mL/kg of predicted body weight without extracorporeal CO2 removal. The primary endpoint was 20% reduction in PaCO2 at 20 minutes after extracorporeal CO2 removal initiation. Tidal volume was subsequently reduced to 4 mL/kg for the remaining 72 hours. Measurements and Main Results: Twelve combined therapies were conducted in the 11 patients. Age was 70 ± 9 years, Simplified Acute Physiology Score II was 69 ± 13, Sequential Organ Failure Assessment score was 14 ± 4, lung injury score was 3 ± 0.5, and PaO2/FIO2 was 135 ± 41. Adding extracorporeal CO2 removal at tidal volume 6 mL/kg decreased PaCO2 by 21% (95% CI, 17–25%), from 47 ± 11 to 37 ± 8 Torr (p < 0.001). Lowering tidal volume to 4 mL/kg reduced minute ventilation from 7.8 ± 1.5 to 5.2 ± 1.1 L/min and plateau pressure from 25 ± 4 to 21 ± 3 cm H2O and raised PaCO2 from 37 ± 8 to 48 ± 10 Torr (all p < 0.001). On an average of both positions, the oxygenator’s blood flow was 410 ± 30 mL/min and the CO2 removal rate was 83 ± 20 mL/min. The oxygenator blood flow (p <0 .001="" and="" br="" co2="" concern.="" hemofilter.="" higher="" membrane="" no="" of="" oxygenator="" p="0.083)" placed="" rate="" removal="" safety="" the="" there="" upstream="" was="" were="" when="">Conclusions: Combining extracorporeal CO2 removal and continuous venovenous hemofiltration in patients with acute respiratory distress syndrome and acute kidney injury is safe and allows efficient blood purification together with enhanced lung protective ventilation.

Risks and benefits of stress ulcer prophylaxis in adult neurocritical care patients: a systematic review and meta-analysis of randomized controlled trials

Risks and benefits of stress ulcer prophylaxis in adult neurocritical care patients:a systematic review and meta-analysis of randomized controlled trials
Bolin Liu
Critical Care 2015, 19:409


Introduction: Neurocritical care patients are at high risk for stress-related upper gastrointestinal (UGI) bleeding. The aim of this meta-analysis was to evaluate the risks and benefits of stress ulcer prophylaxis (SUP) in this patient group.
Methods: A systematic search of major electronic literature databases was conducted. Eligible studies were randomized controlled trials (RCTs) in which researchers compared the effects of SUP (with proton pump inhibitors or histamine 2 receptor antagonists) with placebo or no prophylaxis in neurocritical care patients. The primary outcome was UGI bleeding, and secondary outcomes were all-cause mortality and nosocomial pneumonia. Study heterogeneity was sought and quantified. The results were reported as risk ratios/relative risks (RRs) with 95 % confidence intervals (CIs).
Results: We included 8 RCTs comprising an aggregate of 829 neurocritical care patients. Among these trials, one study conducted in a non–intensive care unit setting that did not meet our inclusion criteria was ultimately included based on further evaluation. All studies were judged as having a high or unclear risk of bias. SUP was more effective than placebo or no prophylaxis at reducing UGI bleeding (random effects: RR 0.31; 95 % CI 0.20–0.47; P < 0.00001; I 2 = 45 %) and all-cause mortality (fixed effects: RR 0.70; 95 % CI 0.50–0.98; P = 0.04; I 2 = 0 %). There was no difference between SUP and placebo or no prophylaxis regarding nosocomial pneumonia (random effects: RR 1.14; 95 % CI 0.67–1.94; P = 0.62; I 2 = 42 %). The slight asymmetry of the funnel plots raised the concern of small trial bias, and apparent heterogeneity existed in participants, interventions, control treatments, and outcome measures.
Conclusions: In neurocritical care patients, SUP seems to be more effective than placebo or no prophylaxis in preventing UGI bleeding and reducing all-cause mortality while not increasing the risk of nosocomial pneumonia. The robustness of this conclusion is limited by a lack of trials with a low risk of bias, sparse data, heterogeneity among trials, and a concern regarding small trial bias. Trial registration International Prospective Register of Systematic Reviews (PROSPERO) identifier: CRD42015015802. Date of registration: 6 Jan 2015.

Pain-related Somato Sensory Evoked Potentials: a potential new tool to improve the prognostic prediction of coma after cardiac arrest

Pain-related Somato Sensory Evoked Potentials: a potential new tool to improve the prognostic prediction of coma after cardiac arrest
Zanatta P et al.
Critical Care 2015, 19:403


Introduction: Early prediction of a good outcome in comatose patients after cardiac arrest still remains an unsolved problem. The main aim of the present study was to examine the accuracy of middle-latency SSEP triggered by a painful electrical stimulation on median nerves to predict a favorable outcome.
Methods: No- and low-flow times, pupillary reflex, Glasgow motor score and biochemical data were evaluated at ICU admission. The following were considered within 72 h of cardiac arrest: highest creatinine value, hyperthermia occurrence, EEG, SSEP at low- (10 mA) and high-intensity (50 mA) stimulation, and blood pressure reactivity to 50 mA. Intensive care treatments were also considered. Data were compared to survival, consciousness recovery and 6-month CPC (Cerebral Performance Category).
Results: Pupillary reflex and EEG were statistically significant in predicting survival; the absence of blood pressure reactivity seems to predict brain death within 7 days of cardiac arrest. Middle- and short-latency SSEP were statistically significant in predicting consciousness recovery, and middle-latency SSEP was statistically significant in predicting 6-month CPC outcome. The prognostic capability of 50 mA middle-latency-SSEP was demonstrated to occur earlier than that of EEG reactivity.
Conclusions: Neurophysiological evaluation constitutes the key to early information about the neurological prognostication of postanoxic coma. In particular, the presence of 50 mA middle-latency SSEP seems to be an early and reliable predictor of good neurological outcome, and its absence constitutes a marker of poor prognosis. Moreover, the absence 50 mA blood pressure reactivity seems to identify patients evolving towards the brain death.