Dilemmas in infection control in the intensive care unit

Dilemmas in infection control in the intensive care unit

Zahar J-R,  Blot S
Intensive and Critical Care Nursing, Article in press

Intensive care unit (ICU) patients are at a particular risk for infection with multidrug resistant micro-organisms because they experience high severity of acute illness, present with predisposing underlying conditions, are exposed to a plethora of invasive procedures and are at the extremes of age, either neonatal or very old (Depuydt et al., 2006; Blot, 2008; Blot et al., 2014b; Verstraete et al., 2015; Afonso and Blot, 2017). Healthcare-associated infection and multidrug resistance are a major concern in ICUs as it is associated with considerable morbidity and possibly mortality (Blot et al., 2002, 2003; Verstraete et al., 2016) As a consequence substantial efforts in infection prevention and control are required to reduce the burden of infectious complications (Rello et al., 2013; Blot et al., 2014a ;  Sousa et al., 2018). While infection prevention targets the avoidance of specific infections at an individual patient level, infection control is more focused on containing the problem and preventing further spread of epidemiologically important pathogens throughout the unit or the hospital.

Infection control is a key element in the management of multidrug resistant organism (MDRO) carriers/infected patients in ICU....

Editorial

The Effect of ICU Out-of-Hours Admission on Mortality: A Systematic Review and Meta-Analysis

The Effect of ICU Out-of-Hours Admission on Mortality: A Systematic Review and Meta-Analysis

Galloway, M et al

Critical Care Medicine: February 2018 - Volume 46 - Issue 2 - p 290–299

Objectives: Organizational factors are associated with outcome of critically ill patients and may vary by time of day and day of week. We aimed to identify the association between out-of-hours admission to critical care and mortality. 
Data Sources: MEDLINE (via Ovid) and EMBASE (via Ovid). Study Selection: We performed a systematic search of the literature for studies on out-of-hours adult general ICU admission on patient mortality. 
Data Extraction: Meta-analyses were performed and Forest plots drawn using RevMan software. Data are presented as odds ratios ([95% CIs], p values). 
Data Synthesis: A total of 16 studies with 902,551 patients were included in the analysis with a crude mortality of 18.2%. Fourteen studies with 717,331 patients reported mortality rates by time of admission and 11 studies with 835,032 patients by day of admission. Admission to ICU at night was not associated with an increased odds of mortality compared with admissions during the day (odds ratio, 1.04 [0.98–1.11]; p = 0.18). However, admissions during the weekend were associated with an increased odds of death compared with ICU admissions during weekdays (1.05 [1.01–1.09]; p = 0.006). Increased mortality associated with weekend ICU admissions compared with weekday ICU admissions was limited to North American countries (1.08 [1.03–1.12]; p = 0.0004). The absence of a routine overnight on-site intensivist was associated with increased mortality among weekend ICU admissions compared with weekday ICU admissions (1.11 [1.00–1.22]; p = 0.04) and nighttime admissions compared with daytime ICU admissions (1.11 [1.00–1.23]; p = 0.05). 
Conclusions: Adjusted risk of death for ICU admission was greater over the weekends compared with weekdays. The absence of a dedicated intensivist on-site overnight may be associated with increased mortality for acute admissions. These results need to be interpreted in context of the organization of local healthcare resources before changes to healthcare policy are implemented.

Predictors of Intubation in Patients With Acute Hypoxemic Respiratory Failure Treated With a Noninvasive Oxygenation Strategy

Predictors of Intubation in Patients With Acute Hypoxemic Respiratory Failure Treated With a Noninvasive Oxygenation Strategy

Frat, J-P et al

Critical Care Medicine: February 2018 - Volume 46 - Issue 2 - p 208–215

Objectives: In patients with acute hypoxemic respiratory failure, noninvasive ventilation and high-flow nasal cannula oxygen are alternative strategies to conventional oxygen therapy. Endotracheal intubation is frequently needed in these patients with a risk of delay, and early predictors of failure may help clinicians to decide early. We aimed to identify factors associated with intubation in patients with acute hypoxemic respiratory failure treated with different noninvasive oxygenation techniques. 

Design: Post hoc analysis of a randomized clinical trial. Setting: Twenty-three ICUs. Patients: Patients with a respiratory rate greater than 25 breaths/min and a PaO2/FIO2 ratio less than or equal to 300 mm Hg. Intervention: Patients were treated with standard oxygen, high-flow nasal cannula oxygen, or noninvasive ventilation. 

Measurement and Main Results: Respiratory variables one hour after treatment initiation. Under standard oxygen, patients with a respiratory rate greater than or equal to 30 breaths/min were more likely to need intubation (odds ratio, 2.76; 95% CI, 1.13–6.75; p = 0.03). One hour after high-flow nasal cannula oxygen initiation, increased heart rate was the only factor associated with intubation. One hour after noninvasive ventilation initiation, a PaO2/FIO2 ratio less than or equal to 200 mm Hg and a tidal volume greater than 9 mL/kg of predicted body weight were independent predictors of intubation (adjusted odds ratio, 4.26; 95% CI, 1.62–11.16; p = 0.003 and adjusted odds ratio, 3.14; 95% CI, 1.22–8.06; p = 0.02, respectively). A tidal volume above 9 mL/kg during noninvasive ventilation remained independently associated with 90-day mortality. Conclusions: In patients with acute hypoxemic respiratory failure breathing spontaneously, the respiratory rate was a predictor of intubation under standard oxygen, but not under high-flow nasal cannula oxygen or noninvasive ventilation. A PaO2/FIO2 below 200 mm Hg and a high tidal volume greater than 9 mL/kg were the two strong predictors of intubation under noninvasive ventilation.

Prevention of Ventilator-Associated Pneumonia: The Multimodal Approach of the Spanish ICU “Pneumonia Zero” Program

Prevention of Ventilator-Associated Pneumonia: The Multimodal Approach of the Spanish ICU “Pneumonia Zero” Program

Alvarez-Lerma, F et al

Critical Care Medicine: February 2018 - Volume 46 - Issue 2 - p 181–188

Objectives: The “Pneumonia Zero” project is a nationwide multimodal intervention based on the simultaneous implementation of a comprehensive evidence-based bundle measures to prevent ventilator-associated pneumonia in critically ill patients admitted to the ICU. Design: Prospective, interventional, and multicenter study. Setting: A total of 181 ICUs throughout Spain. Patients: All patients admitted for more than 24 hours to the participating ICUs between April 1, 2011, and December 31, 2012. 
Intervention: Ten ventilator-associated pneumonia prevention measures were implemented (seven were mandatory and three highly recommended). The database of the National ICU-Acquired Infections Surveillance Study (Estudio Nacional de Vigilancia de Infecciones Nosocomiales [ENVIN]) was used for data collection. Ventilator-associated pneumonia rate was expressed as incidence density per 1,000 ventilator days. Ventilator-associated pneumonia rates from the incorporation of the ICUs to the project, every 3 months, were compared with data of the ENVIN registry (April–June 2010) as the baseline period. Ventilator-associated pneumonia rates were adjusted by characteristics of the hospital, including size, type (public or private), and teaching (postgraduate) or university-affiliated (undergraduate) status. 
Measurements and Main Results: The 181 participating ICUs accounted for 75% of all ICUs in Spain. In a total of 171,237 ICU admissions, an artificial airway was present on 505,802 days (50.0% of days of stay in the ICU). A total of 3,474 ventilator-associated pneumonia episodes were diagnosed in 3,186 patients. The adjusted ventilator-associated pneumonia incidence density rate decreased from 9.83 (95% CI, 8.42–11.48) per 1,000 ventilator days in the baseline period to 4.34 (95% CI, 3.22–5.84) after 19–21 months of participation. 
Conclusions: Implementation of the bundle measures included in the “Pneumonia Zero” project resulted in a significant reduction of more than 50% of the incidence of ventilator-associated pneumonia in Spanish ICUs. This reduction was sustained 21 months after implementation.

Should Transfusion Trigger Thresholds Differ for Critical Care Versus Perioperative Patients? A Meta-Analysis of Randomized Trials

Should Transfusion Trigger Thresholds Differ for Critical Care Versus Perioperative Patients? A Meta-Analysis of Randomized Trials

Chong, M et al

Critical Care Medicine: February 2018 - Volume 46 - Issue 2 - p 252–263

Objective: To address the significant uncertainty as to whether transfusion thresholds for critical care versus surgical patients should differ. Design: Meta-analysis of randomized controlled trials. Setting: Medline, EMBASE, and Cochrane Library searches were performed up to 15 June 2016. Patients: Trials had to enroll adult surgical or critically ill patients for inclusion. Interventions: Studies had to compare a liberal versus restrictive threshold for the transfusion of allogeneic packed RBCs. 
Measurements and Main Results: The primary outcome was 30-day all-cause mortality, sub-grouped by surgical and critical care patients. Secondary outcomes included myocardial infarction, stroke, renal failure, allogeneic blood exposure, and length of stay. Odds ratios and weighted mean differences were calculated using random effects meta-analysis. To assess whether subgroups were significantly different, tests for subgroup interaction were used. Subgroup analysis by trials enrolling critically ill versus surgical patients was performed. Twenty-seven randomized controlled trials (10,797 patients) were included. In critical care patients, restrictive transfusion resulted in significantly reduced 30-day mortality compared with liberal transfusion (odds ratio, 0.82; 95% CI, 0.70–0.97). In surgical patients, a restrictive transfusion strategy led to the opposite direction of effect for mortality (odds ratio, 1.31; 95% CI, 0.94–1.82). The subgroup interaction test was significant (p = 0.04), suggesting that the effect of restrictive transfusion on mortality is statistically different for critical care (decreased risk) versus surgical patients (potentially increased risk or no difference). Regarding secondary outcomes, for critically ill patients, a restrictive strategy resulted in reduced risk of stroke/transient ischemic attack, packed RBC exposure, transfusion reactions, and hospital length of stay. In surgical patients, restrictive transfusion resulted in reduced packed RBC exposure. 
Conclusions: The safety of restrictive transfusion strategies likely differs for critically ill patients versus perioperative patients. Further trials investigating transfusion strategies in the perioperative setting are necessary.

Predictors, Prevalence, and Outcomes of Early Crystalloid Responsiveness Among Initially Hypotensive Patients With Sepsis and Septic Shock

Predictors, Prevalence, and Outcomes of Early Crystalloid Responsiveness Among Initially Hypotensive Patients With Sepsis and Septic Shock

Leisman, D et al

Critical Care Medicine: February 2018 - Volume 46 - Issue 2 - p 189–198

Objectives: The prevalence of responsiveness to initial fluid challenge among hypotensive sepsis patients is unclear. To avoid fluid overload, and unnecessary treatment, it is important to differentiate these phenotypes. We aimed to 1) determine the proportion of hypotensive sepsis patients sustaining favorable hemodynamic response after initial fluid challenge, 2) determine demographic and clinical risk factors that predicted refractory hypotension, and 3) assess the association between timeliness of fluid resuscitation and refractoriness. 
Design: Secondary analysis of a prospective, multisite, observational, consecutive-sample cohort. Setting: Nine tertiary and community hospitals over 1.5 years. Patients: Inclusion criteria 1) suspected or confirmed infection, 2) greater than or equal to two systemic inflammatory response syndrome criteria, 3) systolic blood pressure less than 90 mm Hg, greater than 40% decrease from baseline, or mean arterial pressure less than 65 mm Hg. 
Measurements and Main Results: Sex, age, heart failure, renal failure, immunocompromise, source of infection, initial lactate, coagulopathy, temperature, altered mentation, altered gas exchange, and acute kidney injury were used to generate a risk score. The primary outcome was sustained normotension after fluid challenge without vasopressor titration. Among 3,686 patients, 2,350 (64%) were fluid responsive. Six candidate risk factors significantly predicted refractoriness in multivariable analysis: heart failure (odds ratio, 1.43; CI, 1.20–1.72), hypothermia (odds ratio, 1.37; 1.10–1.69), altered gas exchange (odds ratio, 1.33; 1.12–1.57), initial lactate greater than or equal to 4.0 mmol/L (odds ratio, 1.28; 1.08–1.52), immunocompromise (odds ratio, 1.23; 1.03–1.47), and coagulopathy (odds ratio, 1.23; 1.03–1.48). High-risk patients (≥ three risk factors) had 70% higher (CI, 48–96%) refractory risk (19% higher absolute risk; CI, 14–25%) versus low-risk (zero risk factors) patients. Initiating fluids in greater than 2 hours also predicted refractoriness (odds ratio, 1.96; CI, 1.49–2.58). Mortality was 15% higher (CI, 10-18%) for refractory patients. 
Conclusions: Two in three hypotensive sepsis patients were responsive to initial fluid resuscitation. Heart failure, hypothermia, immunocompromise, hyperlactemia, and coagulopathy were associated with the refractory phenotype. Fluid resuscitation initiated after the initial 2 hours more strongly predicted refractoriness than any patient factor tested.

Acute Physiologic Stress and Subsequent Anxiety Among Family Members of ICU Patients

Acute Physiologic Stress and Subsequent Anxiety Among Family Members of ICU Patients

Beesley, S et al

Critical Care Medicine: February 2018 - Volume 46 - Issue 2 - p 229–235

Objectives: The ICU is a complex and stressful environment and is associated with significant psychologic morbidity for patients and their families. We sought to determine whether salivary cortisol, a physiologic measure of acute stress, was associated with subsequent psychologic distress among family members of ICU patients. Design: This is a prospective, observational study of family members of adult ICU patients. Setting: Adult medical and surgical ICU in a tertiary care center. Subjects: Family members of ICU patients. Interventions: Participants provided five salivary cortisol samples over 24 hours at the time of the patient ICU admission. The primary measure of cortisol was the area under the curve from ground; the secondary measure was the cortisol awakening response. Outcomes were obtained during a 3-month follow-up telephone call. The primary outcome was anxiety, measured by the Hospital Anxiety and Depression Scale-Anxiety. Secondary outcomes included depression and posttraumatic stress disorder. Measurements and Main Results: Among 100 participants, 92 completed follow-up. Twenty-nine participants (32%) reported symptoms of anxiety at 3 months, 15 participants (16%) reported depression symptoms, and 14 participants (15%) reported posttraumatic stress symptoms. In our primary analysis, cortisol level as measured by area under the curve from ground was not significantly associated with anxiety (odds ratio, 0.94; p = 0.70). In our secondary analysis, however, cortisol awakening response was significantly associated with anxiety (odds ratio, 1.08; p = 0.02). Conclusions: Roughly one third of family members experience anxiety after an ICU admission for their loved one, and many family members also experience depression and posttraumatic stress. Cortisol awakening response is associated with anxiety in family members of ICU patients 3 months following the ICU admission. Physiologic measurements of stress among ICU family members may help identify individuals at particular risk of adverse psychologic outcomes.

Significance of Mini Bronchoalveolar Lavage Fluid Amylase Level in Ventilator-Associated Pneumonia: A Prospective Observational Study

Significance of Mini Bronchoalveolar Lavage Fluid Amylase Level in Ventilator-Associated Pneumonia: A Prospective Observational Study

Samanta, S et al

Critical Care Medicine: January 2018 - Volume 46 - Issue 1 - p 71–78

Objectives: Aspiration of oropharyngeal or gastric contents in intubated patients can lead to ventilator-associated pneumonia. Amylase in respiratory secretion has been reported as a possible marker of aspiration. We studied whether elevated α-amylase in mini bronchoalveolar lavage specimens can be suggestive of ventilator-associated pneumonia in intubated patients with high clinical suspicion. Design: Prospective single-center observational study. Setting: Department of Critical Care Medicine, tertiary care academic institute. Patients: Adult patients on mechanical ventilation for more than 48 hours with with clinically suspected ventilator-associated pneumonia as per defined criteria, admitted between December 2014 and May 2016. Methods: Mini bronchoalveolar lavage samples were collected within 72 hours of endotracheal intubation. Samples were sent for α-amylase level assay and quantitative culture. Ventilator-associated pneumonia was confirmed from mini bronchoalveolar lavage microbial culture of greater than or equal to 104 cfu/mL, and patients were divided into ventilator-associated pneumonia and no ventilator-associated pneumonia groups. Pre- and postintubation risk factors for aspiration were also noted. Results: The prevalence of ventilator-associated pneumonia was 64.9% among 151 patients in whom it was clinically suspected. Median (interquartile range) mini bronchoalveolar lavage α-amylase levels in ventilator-associated pneumonia and no ventilator-associated pneumonia groups on the day of study inclusion were 287 U/L (164–860 U/L) and 94 U/L (59–236 U/L), respectively (p < 0.001). Median (interquartile range) α-amylase levels in patients with 0, 1, 2, and 3 preintubation risk factors were 65 U/L (35–106 U/L), 200 U/L (113–349 U/L), 867 U/L (353–1,425 U/L), and 3,453 U/L (1,865–4,304 U/L), respectively (p < 0.001) and 472 U/L (164–1,452 U/L) and 731 U/L (203–1,403 U/L) in patients with 1 and 2 postintubation risk factors, respectively (p < 0.001). A mini bronchoalveolar lavage α-amylase of 163 U/L or more yielded sensitivity and specificity of 73% and 68.6%, respectively, with area under the receiver operating characteristic curve of 0.746 (95% CI, 0.66–0.83). Conclusions: Patients with ventilator-associated pneumonia within 72 hours from intubation have significantly elevated α-amylase concentrations in mini bronchoalveolar lavage fluid. Mini bronchoalveolar lavage α-amylase concentrations increase with increasing number of aspiration risk factors.

Intermittent Versus Continuous and Intermittent Medications for Pain and Sedation After Pediatric Cardiothoracic Surgery; A Randomized Controlled Trial

Intermittent Versus Continuous and Intermittent Medications for Pain and Sedation After Pediatric Cardiothoracic Surgery; A Randomized Controlled Trial

Penk, J et al

Critical Care Medicine: January 2018 - Volume 46 - Issue 1 - p 123–129

Objectives: Compare continuous infusions of morphine and midazolam in addition to intermittent doses with an intermittent only strategy for pain and sedation after pediatric cardiac surgery. Design: Randomized controlled trial. Setting: Advocate Children’s Hospital, Oak Lawn, IL. Patients: Sixty patients 3 months to 4 years old with early extubation after pediatric cardiac surgery. Interventions: Patients received a continuous infusion of morphine and midazolam or placebo for 24 hours. Both groups received intermittent morphine and midazolam doses as needed. Measurements and Main Results: Gender, age, bypass time, and surgical complexity were not different between groups. Scheduled ketorolac and acetaminophen were used in both groups and were not associated with adverse events. The mean, median, and maximum Faces, Legs, Activity, Cry, And Consolability score were not different between groups. There was no significant difference in number of intermittent doses received between groups. The total morphine dose was higher in the continuous/intermittent group (0.90 vs 0.23 mg/kg; p < 0.01). The total midazolam dose was also higher in the continuous/intermittent group (0.90 vs 0.18 mg/kg; p < 0.01). The hospital length of stay was longer in the continuous/intermittent group (8.4 vs 4.9 d; p = 0.04). Conclusions: Pain was not better controlled with the addition of continuous infusions of morphine and midazolam when compared with intermittent dosing only. Use of continuous infusions resulted in a significantly higher total dosage of these medications and a longer length of stay.