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Breast Surgery

Sunday 26 November 2017

Effects of High-Flow Nasal Cannula on the Work of Breathing in Patients Recovering From Acute Respiratory Failure

Effects of High-Flow Nasal Cannula on the Work of Breathing in Patients Recovering From Acute Respiratory Failure

Delorme, M et al
Critical Care Medicine: December 2017 - Volume 45 - Issue 12 - p 1981–1988

Objectives: High-flow nasal cannula is increasingly used in the management of respiratory failure. However, little is known about its impact on respiratory effort, which could explain part of the benefits in terms of comfort and efficiency. This study was designed to assess the effects of high-flow nasal cannula on indexes of respiratory effort (i.e., esophageal pressure variations, esophageal pressure-time product/min, and work of breathing/min) in adults. 
Design: A randomized controlled crossover study was conducted in 12 patients with moderate respiratory distress (i.e., after partial recovery from an acute episode, allowing physiologic measurements). Setting: Institut Universitaire de Cardiologie et de Pneumologie de Québec, QC, Canada. Subjects: Twelve adult patients with respiratory distress symptoms were enrolled in this study. 
Interventions: Four experimental conditions were evaluated: baseline with conventional oxygen therapy and high-flow nasal cannula at 20, 40, and 60 L/min. The primary outcomes were the indexes of respiratory effort (i.e., esophageal pressure variations, esophageal pressure-time product/min, and work of breathing/min). Secondary outcomes included tidal volume, respiratory rate, minute volume, dynamic lung compliance, inspiratory resistance, and blood gases. Measurements and Main Results: Esophageal pressure variations decreased from 9.8 (5.8–14.6) cm H2O at baseline to 4.9 (2.1–9.1) cm H2O at 60 L/min (p = 0.035). Esophageal pressure-time product/min decreased from 165 (126–179) to 72 (54–137) cm H2O • s/min, respectively (p = 0.033). Work of breathing/min decreased from 4.3 (3.5–6.3) to 2.1 (1.5–5.0) J/min, respectively (p = 0.031). Respiratory pattern variables and capillary blood gases were not significantly modified between experimental conditions. Dynamic lung compliance increased from 38 (24–64) mL/cm H2O at baseline to 59 (43–175) mL/cm H2O at 60 L/min (p = 0.007), and inspiratory resistance decreased from 9.6 (5.5–13.4) to 5.0 (1.0–9.1) cm H2O/L/s, respectively (p = 0.07). 
Conclusions: High-flow nasal cannula, when set at 60 L/min, significantly reduces the indexes of respiratory effort in adult patients recovering from acute respiratory failure. This effect is associated with an improvement in respiratory mechanics.

Critical Illness-Related Corticosteroid Insufficiency (CIRCI): A Narrative Review from a Multispecialty Task Force of the Society of Critical Care Medicine (SCCM) and the European Society of Intensive Care Medicine (ESICM)

Critical Illness-Related Corticosteroid Insufficiency (CIRCI): A Narrative Review from a Multispecialty Task Force of the Society of Critical Care Medicine (SCCM) and the European Society of Intensive Care Medicine (ESICM)

Annane, D et al
Critical Care Medicine: December 2017 - Volume 45 - Issue 12 - p 2089–2098

Objective: To provide a narrative review of the latest concepts and understanding of the pathophysiology of critical illness-related corticosteroid insufficiency (CIRCI). Participants: A multi-specialty task force of international experts in critical care medicine and endocrinology and members of the Society of Critical Care Medicine and the European Society of Intensive Care Medicine. 
Data Sources: Medline, Database of Abstracts of Reviews of Effects (DARE), Cochrane Central Register of Controlled Trials (CENTRAL) and the Cochrane Database of Systematic Reviews. Results: Three major pathophysiologic events were considered to constitute CIRCI: dysregulation of the hypothalamic–pituitary–adrenal (HPA) axis, altered cortisol metabolism, and tissue resistance to glucocorticoids. The dysregulation of the HPA axis is complex, involving multidirectional crosstalk between the CRH/ACTH pathways, autonomic nervous system, vasopressinergic system, and immune system. Recent studies have demonstrated that plasma clearance of cortisol is markedly reduced during critical illness, explained by suppressed expression and activity of the primary cortisol-metabolizing enzymes in the liver and kidney. Despite the elevated cortisol levels during critical illness, tissue resistance to glucocorticoids is believed to occur due to insufficient glucocorticoid alpha-mediated anti-inflammatory activity. Conclusions: Novel insights into the pathophysiology of CIRCI add to the limitations of the current diagnostic tools to identify at-risk patients and may also impact how corticosteroids are used in patients with CIRCI.

Guidelines for the Diagnosis and Management of Critical Illness-Related Corticosteroid Insufficiency (CIRCI) in Critically Ill Patients (Part I): Society of Critical Care Medicine (SCCM) and European Society of Intensive Care Medicine (ESICM) 2017

Guidelines for the Diagnosis and Management of Critical Illness-Related Corticosteroid Insufficiency (CIRCI) in Critically Ill Patients (Part I): Society of Critical Care Medicine (SCCM) and European Society of Intensive Care Medicine (ESICM) 2017

Annane, D et al
Critical Care Medicine: December 2017 - Volume 45 - Issue 12 - p 2078–2088

Objective: To update the 2008 consensus statements for the diagnosis and management of critical illness-related corticosteroid insufficiency (CIRCI) in adult and pediatric patients. Participants: A multispecialty task force of 16 international experts in critical care medicine, endocrinology, and guideline methods, all of them members of the Society of Critical Care Medicine and/or the European Society of Intensive Care Medicine. 
Design/Methods: The recommendations were based on the summarized evidence from the 2008 document in addition to more recent findings from an updated systematic review of relevant studies from 2008 to 2017 and were formulated using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology. The strength of each recommendation was classified as strong or conditional, and the quality of evidence was rated from high to very low based on factors including the individual study design, the risk of bias, the consistency of the results, and the directness and precision of the evidence. Recommendation approval required the agreement of at least 80% of the task force members. 
Results: The task force was unable to reach agreement on a single test that can reliably diagnose CIRCI, although delta cortisol (change in baseline cortisol at 60 min of < 9 μg/dL) after cosyntropin (250 μg) administration and a random plasma cortisol of < 10 μg/dL may be used by clinicians. We suggest against using plasma-free cortisol or salivary cortisol level over plasma total cortisol (conditional, very low quality of evidence). For treatment of specific conditions, we suggest using IV hydrocortisone < 400 mg/day for ≥ 3 days at full dose in patients with septic shock that is not responsive to fluid and moderate- to high-dose vasopressor therapy (conditional, low quality of evidence). We suggest not using corticosteroids in adult patients with sepsis without shock (conditional recommendation, moderate quality of evidence). We suggest the use of IV methylprednisolone 1 mg/kg/day in patients with early moderate to severe acute respiratory distress syndrome (PaO2/FiO2 < 200 and within 14 days of onset) (conditional, moderate quality of evidence). Corticosteroids are not suggested for patients with major trauma (conditional, low quality of evidence). 
Conclusions: Evidence-based recommendations for the use of corticosteroids in critically ill patients with sepsis and septic shock, acute respiratory distress syndrome, and major trauma have been developed by a multispecialty task force.

Effect of Transfusion on Mortality and Other Adverse Events Among Critically Ill Septic Patients: An Observational Study Using a Marginal Structural Cox Model

Effect of Transfusion on Mortality and Other Adverse Events Among Critically Ill Septic Patients: An Observational Study Using a Marginal Structural Cox Model

Dupuis, C et al
Critical Care Medicine: December 2017 - Volume 45 - Issue 12 - p 1972–1980

Objectives: RBC transfusion is often required in patients with sepsis. However, adverse events have been associated with RBC transfusion, raising safety concerns. A randomized controlled trial validated the 7 g/dL threshold, but previously transfused patients were excluded. Cohort studies led to conflicting results and did not handle time-dependent covariates and history of treatment. Additional data are thus warranted to guide patient’s management. Design: To estimate the effect of one or more RBC within 1 day on three major outcomes (mortality, ICU-acquired infections, and severe hypoxemia) at day 30, we used marginal structural models. A trajectory modeling, based on hematocrit evolution pattern, allowed identification of subgroups. Secondary analyses were performed into each of them. Setting: A prospective French multicenter database. Patients: Patients with sepsis at admission. Patients with hemorrhagic shock at admission were excluded. Interventions: None. Measurements and Main Results: Overall, in our cohort of 6,016 patients, RBC transfusion was not associated with death (hazard ratio, 1.07; 95% CI, 0.88–1.30; p = 0.52). However, RBC transfusion was associated with increased occurrence of ICU-acquired infections (hazard ratio, 2.77; 95% CI, 2.33–3.28; p < 0.01) and of severe hypoxemia (hazard ratio, 1.29; 95% CI, 1.14–1.47; p < 0.01). A protective effect from death by the transfusion was found in the subgroup with the lowest hematocrit level (26 [interquartile range, 24–28]) (hazard ratio, 0.72; 95% CI, 0.55–0.95; p = 0.02). Conclusions: RBC transfusion did not affect overall mortality in critically ill patients with sepsis. Increased occurrence rate of ICU-acquired infection and severe hypoxemia are expected outcomes from RBC transfusion that need to be weighted with its benefits in selected patients.

A qualitative study of factors that influence active family involvement with patient care in the ICU: Survey of critical care nurses

A qualitative study of factors that influence active family involvement with patient care in the ICU: Survey of critical care nurses

Hetland, B et al
Intensive and Critical Care Nursing:  Article in Press

Family caregiver involvement may improve patient and family outcomes in the intensive care unit. This study describes critical care nurses’ approaches to involving family caregivers in direct patient care.

Interventions to Improve Hand Hygiene Compliance in the ICU: A Systematic Review

Interventions to Improve Hand Hygiene Compliance in the ICU: A Systematic Review

Lydon, S et al

Critical Care Medicine:  November 2017 - Volume 45 - Issue 11 - p e1165–e1172

Objectives: To synthesize the literature describing interventions to improve hand hygiene in ICUs, to evaluate the quality of the extant research, and to outline the type, and efficacy, of interventions described. 
Data Sources: Systematic searches were conducted in November 2016 using five electronic databases: Medline, CINAHL, PsycInfo, Embase, and Web of Science. Additionally, the reference lists of included studies and existing review papers were screened. 
Study Selection: English language, peer-reviewed studies that evaluated an intervention to improve hand hygiene in an adult ICU setting, and reported hand hygiene compliance rates collected via observation, were included. 
Data Extraction: Data were extracted on the setting, participant characteristics, experimental design, hand hygiene measurement, intervention characteristics, and outcomes. Interventional components were categorized using the Behavior Change Wheel. Methodological quality was examined using the Downs and Black Checklist. 
Data Synthesis: Thirty-eight studies were included. The methodological quality of studies was poor, with studies scoring a mean of 8.6 of 24 (SD= 2.7). Over 90% of studies implemented a bundled intervention. The most frequently employed interventional strategies were education (78.9%), enablement (71.1%), training (68.4%), environmental restructuring (65.8%), and persuasion (65.8%). Intervention outcomes were variable, with a mean relative percentage change of 94.7% (SD= 195.7; range, 4.3–1155.4%) from pre to post intervention. 
Conclusions: This review demonstrates that best practice for improving hand hygiene in ICUs remains unestablished. Future research employing rigorous experimental designs, careful statistical analysis, and clearly described interventions is important.

Advanced Percutaneous Mechanical Circulatory Support Devices for Cardiogenic Shock

Advanced Percutaneous Mechanical Circulatory Support Devices for Cardiogenic Shock

Miller, P. et al

Critical Care Medicine: November 2017 - Volume 45 - Issue 11 - p 1922–1929


To review temporary percutaneous mechanical circulatory support devices for the treatment of cardiogenic shock, including current evidence, contraindications, complications, and future directions. Data Sources: A MEDLINE search was conducted with MeSH terms: cardiogenic shock, percutaneous mechanical circulatory support, extracorporeal membrane oxygenation, Impella, and TandemHeart. 
Study Selection: Selected publications included randomized controlled trial data and observational studies describing experience with percutaneous mechanical circulatory support in cardiogenic shock. 
Data Extraction: Studies were chosen based on strength of association with and relevance to cardiogenic shock. 
Data Synthesis: Until recently, there were few options if cardiogenic shock was refractory to vasopressors or intra-aortic balloon pump counterpulsation. Now, several percutaneous mechanical circulatory support devices, including Impella (Abiomed, Danvers, MA), TandemHeart (CardiacAssist, Pittsburgh, PA), and extracorporeal membrane oxygenation, are more accessible. Compared with intra-aortic balloon pump, Impella provides greater hemodynamic support but no reduction in mortality. Similarly, TandemHeart improves hemodynamic variables but not survival. Comparative studies have been underpowered for mortality because of small sample size. Veno-arterial extracorporeal membrane oxygenation offers the advantage of biventricular circulatory support and oxygenation, but there are significant vascular complications. Comparative studies with extracorporeal membrane oxygenation have not been completed. Despite lack of randomized controlled data, there has been a substantial increase in use of percutaneous mechanical circulatory support. Several ongoing prospective studies with larger sample sizes may provide answers, and newer devices may become smaller, easier to insert, and more effective. Conclusions: Mortality from cardiogenic shock remains unacceptably high despite early coronary revascularization or other therapies. Although evidence is lacking and complications rates are high, improvements and experience with percutaneous mechanical circulatory support may offer the prospect of better outcomes.

Brain Oxygen Optimization in Severe Traumatic Brain Injury Phase-II: A Phase II Randomized Trial

Brain Oxygen Optimization in Severe Traumatic Brain Injury Phase-II: A Phase II Randomized Trial

Okonkwo, D et al

Critical Care Medicine: November 2017 - Volume 45 - Issue 11 - p 1907–1914

Objectives: A relationship between reduced brain tissue oxygenation and poor outcome following severe traumatic brain injury has been reported in observational studies. We designed a Phase II trial to assess whether a neurocritical care management protocol could improve brain tissue oxygenation levels in patients with severe traumatic brain injury and the feasibility of a Phase III efficacy study. Design: Randomized prospective clinical trial. Setting: Ten ICUs in the United States. Patients: One hundred nineteen severe traumatic brain injury patients. Interventions: Patients were randomized to treatment protocol based on intracranial pressure plus brain tissue oxygenation monitoring versus intracranial pressure monitoring alone. Brain tissue oxygenation data were recorded in the intracranial pressure –only group in blinded fashion. Tiered interventions in each arm were specified and impact on intracranial pressure and brain tissue oxygenation measured. Monitors were removed if values were normal for 48 hours consecutively, or after 5 days. Outcome was measured at 6 months using the Glasgow Outcome Scale–Extended. 

Prevention of Exposure Keratopathy in Critically Ill Patients: A Single-Center, Randomized, Pilot Trial Comparing Ocular Lubrication With Bandage Contact Lenses and Punctal Plugs

Prevention of Exposure Keratopathy in Critically Ill Patients: A Single-Center, Randomized, Pilot Trial Comparing Ocular Lubrication With Bandage Contact Lenses and Punctal Plugs

Bendavid, I et al

Critical Care Medicine: November 2017 - Volume 45 - Issue 11 - p 1880–1886

To compare the effectiveness of bandage contact lenses and punctal plugs with ocular lubricants in preventing corneal damage in mechanically ventilated and sedated critically ill patients. Design: Single-center, prospective, randomized, pilot study. Setting: Sixteen-bed, general ICU at a tertiary academic medical center. Patients: Adults admitted to the ICU and anticipated to require mechanical ventilation and continuous sedation for greater than or equal to 4 days. Interventions: Patients were randomized to receive eye care with ocular lubricants (n = 38), bandage contact lenses (n = 33), or punctal plugs (n = 33). The bandage contact lenses were changed every 4 days, whereas the punctal plugs remained in situ for the entire study. Measurements and Main Results: The primary endpoint was the presence or absence of corneal damage as assessed by the grade of keratopathy. Patients were examined by an ophthalmologist blinded to the study group every 4 days and at the time of withdrawal from the study, due to cessation of sedation, discharge from the ICU, or death. The mean duration of the study was 8.6 ± 6.2 days. The grade of keratopathy in the ocular lubricant group increased significantly in both eyes (p = 0.01 for both eyes) while no worsening was noted in either the lens or punctal plugs groups. In a post hoc analysis of patients with an initially abnormal ophthalmic examination, significant healing of keratopathy was noted in the lens group (p = 0.02 and 0.018 for left and right eyes, respectively) and in the right eye of the plugs group (p = 0.005); no improvement was noted in the ocular lubricant group. Conclusions: Compared with ocular lubrication, bandage contact lenses and punctal plugs were more effective in limiting keratopathy, and their use, particularly of bandage contact lenses, was associate
with significant healing of existing lesions.