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Breast Surgery

Wednesday 5 August 2015

Pulmonary ultrasound and pulse oximetry versus chest radiography and arterial blood gas analysis for the diagnosis of acute respiratory distress syndrome: a pilot study

Pulmonary ultrasound and pulse oximetry versus chest radiography and arterial blood gas analysis for the diagnosis of acute respiratory distress syndrome: a pilot study
Critical Care 2015, 19:282 


Introduction In low-resource settings it is not always possible to acquire the information required to diagnose acute respiratory distress syndrome (ARDS). Ultrasound and pulse oximetry, however, may be available in these settings. This study was designed to test whether pulmonary ultrasound and pulse oximetry could be used in place of traditional radiographic and oxygenation evaluation for ARDS. Methods: This study was a prospective, single-center study in the ICU of Harborview Medical Center, a referral hospital in Seattle, Washington, USA. Bedside pulmonary ultrasound was performed on ICU patients receiving invasive mechanical ventilation. Pulse oximetric oxygen saturation (SpO 2 ), partial pressure of oxygen (PaO 2 ), fraction of inspired oxygen (FiO 2 ), provider diagnoses, and chest radiograph closest to time of ultrasound were recorded or interpreted. Results: One hundred and twenty three ultrasound assessments were performed on 77 consecutively enrolled patients with respiratory failure. Oxygenation and radiographic criteria for ARDS were met in 35 assessments. Where SpO 2 ≤ 97 %, the Spearman rank correlation coefficient between SpO 2 /FiO 2 and PaO 2 /FiO 2 was 0.83, p < 0.0001. The sensitivity and specificity of the previously reported threshold of SpO 2 /FiO 2 ≤ 315 for PaO 2 /FiO 2 ≤ 300 was 83 % (95 % confidence interval (CI) 68–93), and 50 % (95 % CI 1–99), respectively. Sensitivity and specificity of SpO 2 /FiO 2 ≤ 235 for PaO 2 /FiO 2 ≤ 200 was 70 % (95 % CI 47–87), and 90 % (95 % CI 68–99), respectively. For pulmonary ultrasound assessments interpreted by the study physician, the sensitivity and specificity of ultrasound interstitial syndrome bilaterally and involving at least three lung fields were 80 % (95 % CI 63–92) and 62 % (95 % CI 49–74) for radiographic criteria for ARDS. Combining SpO 2 /FiO 2 with ultrasound to determine oxygenation and radiographic criteria for ARDS, the sensitivity was 83 % (95 % CI 52–98) and specificity was 62 % (95 % CI 38–82). For moderate–severe ARDS criteria (PaO 2 /FiO 2 ≤ 200), sensitivity was 64 % (95 % CI 31–89) and specificity was 86 % (95 % CI 65–97). Excluding repeat assessments and independent interpretation of ultrasound images did not significantly alter the sensitivity measures. Conclusions: Pulse oximetry and pulmonary ultrasound may be useful tools to screen for, or rule out, impaired oxygenation or lung abnormalities consistent with ARDS in under-resourced settings where arterial blood gas testing and chest radiography are not readily available.

Efficacy of Nonpharmacological Antishivering Interventions: A Systematic Analysis


Critical Care Medicine: August 2015 - Volume 43 - Issue 8 - p 1757–1766 

Objective: We performed a systematic review of the published evidence regarding nonpharmacologic antishivering interventions in various clinical settings. Data Sources: Studies through November 2014 were identified using predefined search terms in electronic databases, including PubMed, the Cochrane Library, EMBASE: Excerpta Medica (Ovid), and Web of Science. Study Selection: All identified articles were critically analyzed by applying prespecified criteria. We included experimental trials with comparable baseline data investigating the antishivering efficacy of nonpharmacological interventions in subjects without underlying thermoregulatory dysfunction. Data Extraction: Sixty-five publications (3,361 subjects) were analyzed by the type of clinical setting, intervention, comparison, and study design. In addition, each study underwent a standardized study quality assessment. Data Synthesis: Nonpharmacological interventions consisted of active cutaneous warming (forced-air warming, electric heating pad/blanket, radiant heating, and water-circulating mattress), body core warming (fluid or gas warming system), passive cutaneous warming (space blankets or towels), and electroacupuncture. Identified clinical settings included perioperative settings without induced hypothermia (60 of 77 comparisons), perioperative settings with induced hypothermia (8 of 77), and induced hypothermia without anesthesia (9 of 77). Active cutaneous warming was the most commonly studied intervention, and it was associated with the highest prevalence of positive results when compared with controls in all three clinical settings. In contrast, passive cutaneous warming and body core warming showed conflicting efficacy. Comparison evaluations among different antishivering interventions were limited due to the paucity and heterogeneity of studies directly comparing different interventions against one another. Conclusion: This systematic review of the effectiveness of nonpharmacological antishivering methods delineates active cutaneous warming as the most effective nonpharmacologic antishivering intervention in the perioperative and induced hypothermia settings.

The Association Between Nutritional Adequacy and Long-Term Outcomes in Critically Ill Patients Requiring Prolonged Mechanical Ventilation: A Multicenter Cohort Study

The Association Between Nutritional Adequacy and Long-Term Outcomes in Critically Ill Patients Requiring Prolonged Mechanical Ventilation: A Multicenter Cohort Study

 

Critical Care Medicine: August 2015 -Volume 43 - Issue 8 - p 1569–1579

Objective: To examine the association between short-term nutritional adequacy received while in the ICU and long-term outcomes including 6-month survival and health-related quality of life in critically ill patients requiring prolonged mechanical ventilation. Design: Retrospective analysis of data prospectively collected in the context of a multicenter randomized controlled trial. Setting: An international sample of ICUs. Patients: Adult patients who were mechanically ventilated for more than 8 days in the ICU. Interventions: None. Measurements and Main Results: Nutritional adequacy was obtained from the average proportion of prescribed calories received over the amount prescribed during the first 8 days. Survival status and health-related quality of life as assessed using the Short-Form 36 v2 were obtained at 3- and 6 months post ICU admission. Of the 1,223 patients enrolled in the randomized controlled trial, 475 met the inclusion criteria for this study. At 6-month follow-up, 302 of the 475 patients (64%) were alive. Survival time in those who received low nutritional adequacy was significantly shorter than those who received high nutritional adequacy while adjusting for important covariates (adjusted hazard ratio, 1.7; 95% CI, 1.1–2.6). At 3-month follow-up, a 25% increase in nutritional adequacy was associated with improvements in Physical Functioning and Role Physical of 7.3 (p = 0.02) and 8.3 (p = 0.004) points, respectively. At 6-month follow-up, adjusted increases in Physical Functioning and Role Physical scores for every 25% increase in nutrition adequacy became smaller and were no longer statistically significant (adjusted estimate for Physical Functioning = 4.2, p = 0.14; for Role Physical = 3.2, p = 0.25). Conclusions: Greater amounts of nutritional intake received during the first week in the ICU were associated with longer survival time and faster physical recovery to 3 months but not 6 months post ICU discharge in critically ill patients requiring prolonged mechanical ventilation. Current recommendations to underfeed critically ill patients may cause harm in some long-stay patients.

Patient Mortality Is Associated With Staff Resources and Workload in the ICU: A Multicenter Observational Study

Patient Mortality Is Associated With Staff Resources and Workload in the ICU: A Multicenter Observational Study


Critical Care Medicine: August 2015 - Volume 43 - Issue 8 - p 1587–1594

Objective: Matching healthcare staff resources to patient needs in the ICU is a key factor for quality of care. We aimed to assess the impact of the staffing-to-patient ratio and workload on ICU mortality. Design: We performed a multicenter longitudinal study using routinely collected hospital data. Setting: Information pertaining to every patient in eight ICUs from four university hospitals from January to December 2013 was analyzed. Patients: A total of 5,718 inpatient stays were included. Interventions: None. Measurements and Main Results: We used a shift-by-shift varying measure of the patient-to-caregiver ratio in combination with workload to establish their relationships with ICU mortality over time, excluding patients with decision to forego life-sustaining therapy. Using a multilevel Poisson regression, we quantified ICU mortality-relative risk, adjusted for patient turnover, severity, and staffing levels. The risk of death was increased by 3.5 (95% CI, 1.3–9.1) when the patient-to-nurse ratio was greater than 2.5, and it was increased by 2.0 (95% CI, 1.3–3.2) when the patient-to-physician ratio exceeded 14. The highest ratios occurred more frequently during the weekend for nurse staffing and during the night for physicians (p < 0.001). High patient turnover (adjusted relative risk, 5.6 [2.0–15.0]) and the volume of life-sustaining procedures performed by staff (adjusted relative risk, 5.9 [4.3–7.9]) were also associated with increased mortality. Conclusions: This study proposes evidence-based thresholds for patient-to-caregiver ratios, above which patient safety may be endangered in the ICU. Real-time monitoring of staffing levels and workload is feasible for adjusting caregivers’ resources to patients’ needs.

Pulse oximetry

Pulse oximetry


Critical Care 2015, 19:272  

Pulse oximetry is universally used for monitoring patients in the critical care setting. This article updates the review on pulse oximetry that was published in 1999 in Critical Care. A summary of the recently developed multiwavelength pulse oximeters and their ability in detecting dyshemoglobins is provided. The impact of the latest signal processing techniques and reflectance technology on improving the performance of pulse oximeters during motion artifact and low perfusion conditions is critically examined. Finally, data regarding the effect of pulse oximetry on patient outcome are discussed.

Intensive care nurses’ opinions and current practice in relation to delirium in the intensive care setting

Intensive care nurses’ opinions and current practice in relation to delirium in the intensive care setting

Published online July 22

Delirium is a frequently encountered syndrome that negatively impacts on the well-being of the critically ill patient. Although international guidelines promote delirium monitoring, little is known regarding Irish intensive care (ICU) nurses’ opinions and current practice in relation to delirium monitoring.

Strategies for weaning from mechanical ventilation: A state of the art review

Published online 21st July

Identification and adoption of strategies to promote timely and successful weaning from mechanical ventilation remain a research and quality improvement priority. The most important steps in the weaning process to prevent unnecessary prolongation of mechanical ventilation are timely recognition of both readiness to wean and readiness to extubate. Strategies shown to be effective in promoting timely weaning include weaning protocols and use of spontaneous breathing trials. This review explores various other strategies that also may promote timely and successful weaning including bundling of spontaneous breathing trials with sedation and delirium monitoring/management as well as early mobility, the use of automated weaning systems and modes that improve patient–ventilator interaction, mechanical insufflation–exsufflation as a weaning adjunct, early extubation to non-invasive ventilation and high flow humidified oxygen.

Foresight and awareness of incipient changes in a patient’ clinical conditions – Perspectives of intensive care nurses

Foresight and awareness of incipient changes in a patient’ clinical conditions – Perspectives of intensive care nurses

Published Online: July 15, 2015

The aim of this study was to explore the phenomenon of becoming aware of incipient changes in patient condition from the perspectives and experiences of intensive care nurses. 

Coreactivation of Human Herpesvirus 6 and Cytomegalovirus Is Associated With Worse Clinical Outcome in Critically Ill Adults

Critical Care Medicine: July 2015 - Volume 43 - Issue 7 - p 1415–1422
Objectives: Human herpesvirus 6 is associated with a variety of complications in immunocompromised patients, but no studies have systematically and comprehensively assessed the impact of human herpesvirus 6 reactivation, and its interaction with cytomegalovirus, in ICU patients. Design: We prospectively assessed human herpesvirus 6 and cytomegalovirus viremia by twice-weekly plasma polymerase chain reaction in a longitudinal cohort study of 115 adult, immunocompetent ICU patients. The association of human herpesvirus 6 and cytomegalovirus reactivation with death or continued hospitalization by day 30 (primary endpoint) was assessed by multivariable logistic regression analyses. Setting: This study was performed in trauma, medical, surgical, and cardiac ICUs at two separate hospitals of a large tertiary care academic medical center. Patients: A total of 115 cytomegalovirus seropositive, immunocompetent adults with critical illness were enrolled in this study. Interventions: None. Measurements and Main Results: Human herpesvirus 6 viremia occurred in 23% of patients at a median of 10 days. Human herpesvirus 6B was the species detected in eight samples available for testing. Most patients with human herpesvirus 6 reactivation also reactivated cytomegalovirus (70%). Severity of illness was not associated with viral reactivation. Mechanical ventilation, burn ICU, major infection, human herpesvirus 6 reactivation, and cytomegalovirus reactivation were associated with the primary endpoint in unadjusted analyses. In a multivariable model adjusting for mechanical ventilation and ICU type, only coreactivation of human herpesvirus 6 and cytomegalovirus was significantly associated with the primary endpoint (adjusted odds ratio, 7.5; 95% CI, 1.9–29.9; p = 0.005) compared to patients with only human herpesvirus 6, only cytomegalovirus, or no viral reactivation. Conclusions: Coreactivation of both human herpesvirus 6 and cytomegalovirus in ICU patients is associated with worse outcome than reactivation of either virus alone. Future studies should define the underlying mechanism(s) and determine whether prevention or treatment of viral reactivation improves clinical outcome.