Citations

Purpose of review In this review, we will discuss efforts and challenges in understanding and developing meaningful outcomes of critical care research, quality improvement and policy, which are patient-centered and goal concordant, rather than mortality alone. We shall discuss different aspects of what could constitute outcomes of critical illness as meaningful to the patients and other stakeholders, including families and providers. Recent findings Different outcome pathways after critical illness impact the patients, families and providers in multiple ways. For patients who die, it is important to consider the experience of dying. For the increasing number of survivors of critical illness, challenges of survival have surfaced. The physical, mental and social debility that survivors experience has evolved into the entity called post-ICU syndrome. The importance of prehospital health state trajectory and the need for the outcome of critical care to be aligned with the patients’ goals and preferences have been increasingly recognized. Summary A theoretical framework is outlined to help understand the impact of critical care interventions on outcomes that are meaningful to patients, families and healthcare providers.

The use of supraglottic airway devices such as the King LTS-D laryngeal tube has increased in the prehospital setting because of their relative ease of successful insertion, even in the hands of inexperienced providers. However, these devices have their own associated complications. In patients with a known or suspected difficult airway, supraglottic airway device exchanges should occur under controlled conditions using an airway exchange catheter, preferably under direct visualization with a flexible fiberoptic bronchoscope. We report unanticipated difficulties with supraglottic airway exchange caused by a kinked King LTS-D laryngeal tube.

Objectives: To evaluate the epidemiology of hyperammonemia unrelated to liver failure in the critical care setting. Design: Retrospective case series. Setting: Critically ill patients admitted to ICUs at Mayo Clinic, Rochester, MN (medical ICU, two mixed medical-surgical ICUs, coronary care unit, or the cardiosurgical ICU) between July 1, 2004, and October 31, 2015. Patients: Adult critically ill patients with hyperammonemia not related to acute or chronic liver failure. We excluded patients with diagnosis of moderate or severe liver disease, hyperbilirubinemia, and patients who denied the use of their medical records. Interventions: None. Measurements and Main Results: Of 3,908 ICU patients with hyperammonemia, 167 (4.5%) had no evidence of acute or chronic liver failure. One-hundred one patients (60.5%) were male with median age of 65.7 years (interquartile range, 50–74.5 yr) and median serum ammonia level of 68 µg/dL (interquartile range, 58–87 µg/dL). Acute encephalopathy was present in 119 patients (71%). Predisposing conditions included malnutrition 27 (16%), gastric bypass six (3.6%), total parenteral nutrition four (2.4%); exposure to valproic acid 17 (10%); status epilepticus 11 (6.6%), high tumour burden 19 (11.3%), and renal failure 82 (49.1%). Urea cycle defects were diagnosed in seven patients (4.1%). Hospital mortality was high (30%), and median ammonia level was higher among the nonsurvivors (74 vs 67 µg/dL; p = 0.05). Deaths were more likely in hyperammonemic patients who were older (p = 0.016), had greater illness severity (higher Acute Physiology and Chronic Health Evaluation III score, p < 0.01), malignancy (p < 0.01), and solid organ transplantation (p = 0.04), whereas seizure disorder was more common in survivors (p = 0.02). After adjustment, serum ammonia level was not associated with increased mortality. Conclusions: Hyperammonemia occurs in a substantial minority of critically ill patients without liver failure. These patients have a poor prognosis, although ammonia level per se is not independently associated with mortality. Serum ammonia should be measured when risk factors are present, such as nutritional deficiencies and protein refeeding, treatment with valproic acid, high tumour burden, and known or suspected urea cycle abnormalities.

BACKGROUND: Patients who develop ARDS from medical or traumatic causes typically present after the inciting event has already occurred. Postoperative ARDS is unique in that the inciting insult potentially responsible for ARDS is known ahead of time, which provides an opportunity to study the early pathophysiology of ARDS. The objective of this study was to better understand the early pathophysiology of postoperative ARDS through a temporal analysis of key biomarkers of interest. METHODS: We performed a case-control study of adults undergoing elective thoracic, aortic vascular, or cardiac surgery, which placed them at increased risk of developing postoperative ARDS. Biomarkers were measured at baseline, 2 h, and 6 h after the key intraoperative event believed to be responsible for ARDS. RESULTS: Of the 467 subjects enrolled, 26 developed ARDS and were matched to non-ARDS controls 1:2 based on age, sex, surgical procedure, and surgical lung injury prediction score. Patients with ARDS were more likely to have lower preoperative albumin ( P = .029), longer surgery ( P = .007), larger amounts of intraoperative fluid ( P = .036), and higher intraoperative peak inspiratory pressures ( P = .006). Baseline plasminogen activator inhibitor-1 levels were higher in the ARDS group ( P = .03). Changes in postoperative biomarker levels from baseline were greater in the ARDS group for interleukin-8 (baseline to 6 h, P = .02) and surfactant protein-D (baseline to 2 h, P = .009). CONCLUSIONS: Our study supported the hypothesis that dysregulated coagulation, inflammation, and epithelial injury are pathophysiologic features of early postoperative ARDS. Interleukin-8, plasminogen activator-1, and surfactant protein-D may help predict development of postoperative ARDS.

Abstract Rationale Acute respiratory distress syndrome (ARDS) is a devastating illness with limited therapeutic options. A better understanding of early biochemical and immunological events in ARDS could inform the development of new preventive and treatment strategies. Objectives To determine select peripheral blood lipid mediator and leukocyte responses in patients at risk for ARDS. Methods Patients at risk for ARDS were randomized as part of a multicenter, double-blind clinical trial of aspirin versus placebo (the LIPS-A [Lung Injury Prevention Study with Aspirin] trial; NCT01504867). Plasma thromboxane B2 (TXB2), aspirin-triggered lipoxin A4 (15-epi-LXA4, ATL), and peripheral blood leukocyte number and activation were determined on enrollment and after treatment with either aspirin or placebo. Measurements and Main Results Thirty-three of 367 subjects (9.0%) developed ARDS after randomization. Baseline ATL levels, total monocyte counts, intermediate monocyte counts, and monocyte–platelet aggregates were associated with the development of ARDS. Peripheral blood neutrophil count and monocyte–platelet aggregates significantly decreased over time. Of note, nine subjects developed ARDS after randomization yet before study drug initiation, including seven subjects assigned to aspirin treatment. Subjects without ARDS at the time of first dose demonstrated a lower incidence of ARDS with aspirin treatment. Compared with placebo, aspirin significantly decreased TXB2 and increased the ATL/TXB2 ratio. Conclusions Biomarkers of intravascular monocyte activation in at-risk patients were associated with development of ARDS. The potential clinical benefit of early aspirin for prevention of ARDS remains uncertain. Together, results of the biochemical and immunological analyses provide a window into the early pathogenesis of human ARDS and represent potential vascular biomarkers of ARDS risk. Clinical trial registered with www.clinicaltrials.gov (NCT01504867).

Objectives: Midodrine is an oral alpha-agonist approved for orthostatic hypotension. The use of midodrine as a vasopressor sparing agent has steadily increased in the ICU despite limited evidence for its safety in that setting. We describe the trends in use and reported side effects and complications of midodrine in multidisciplinary ICUs of a tertiary care institution. Design: Single-center retrospective case series. Setting: Medical and surgical ICU patients from January 2011 to October 2016 at Mayo Clinic, Rochester. Patients: Adult patients admitted to any ICU who received midodrine for hypotension were eligible. Interventions: None. Measurements and Main Results: We reviewed the mean arterial pressures and cumulative vasopressor dose before and after midodrine administration and assessed for reported complications. During the study period, a total of 1,119 patients were initiated on midodrine, 56% in surgical ICUs, 42% in medical ICUs, and 2% in a mixed medical and surgical neurology ICU. There was a significant decrease in the number of patients on vasopressors 24 hours after initiation of midodrine (663 to 344; p < 0.001); among the patients that remained on vasopressors, there was a significant decrease in the median cumulative vasopressor dose (p = 0.002). There was a significant increase in median mean arterial pressure 24 hours after initiation of midodrine among patients who were not on vasopressors (65–68; p < 0.01). Asymptomatic bradycardia (heart rate < 50 beats/min) was the most common side effect (n = 172 patients, median 39 beats/min). Two patients developed bowel ischemia after initiation of midodrine that prompted discontinuation of midodrine in one case. Evaluating trends of utilization, the off-label use of midodrine has increased steadily over the years across ICUs. Conclusions: Our results suggest that midodrine is being increasingly used as an adjunct to increase mean arterial pressure and facilitate weaning of vasopressors in the ICU. Prospective trials are required to further establish the appropriate timing, efficacy, safety, and cost-effectiveness of midodrine use in ICU patients.

Background Optimal methods of mortality risk stratification in patients in the cardiac intensive care unit ( CICU ) remain uncertain. We evaluated the ability of the Sequential Organ Failure Assessment ( SOFA ) score to predict mortality in a large cohort of unselected patients in the CICU. Methods and Results Adult patients admitted to the CICU from January 1, 2007, to December 31, 2015, at a single tertiary care hospital were retrospectively reviewed. SOFA scores were calculated daily, and Acute Physiology and Chronic Health Evaluation ( APACHE )‐ III and APACHE ‐ IV scores were calculated on CICU day 1. Discrimination of hospital mortality was assessed using area under the receiver‐operator characteristic curve values. We included 9961 patients, with a mean age of 67.5±15.2 years; all‐cause hospital mortality was 9.0%. Day 1 SOFA score predicted hospital mortality, with an area under the receiver‐operator characteristic curve value of 0.83; area under the receiver‐operator characteristic curve values were similar for the APACHE ‐ III score, and APACHE ‐ IV predicted mortality ( P >0.05). Mean and maximum SOFA scores over multiple CICU days had greater discrimination for hospital mortality ( P <0.01). Patients with an increasing SOFA score from day 1 and day 2 had higher mortality. Patients with day 1 SOFA score <2 were at low risk of mortality. Increasing tertiles of day 1 SOFA score predicted higher long‐term mortality ( P <0.001 by log‐rank test). Conclusions The day 1 SOFA score has good discrimination for short‐term mortality in unselected patients in the CICU, which is comparable to APACHE ‐ III and APACHE ‐ IV . Advantages of the SOFA score over APACHE include simplicity, improved discrimination using serial scores, and prediction of long‐term mortality.

Objectives: To assess the effectiveness of noninvasive ventilation in patients with acute respiratory failure and do-not-intubate or comfort-measures-only orders. Data Sources: MEDLINE, EMBASE, CINAHL, Scopus, and Web of Science from inception to January 1, 2017. Study Selection: Studies of all design types that enrolled patients in the ICU or hospital ward who received noninvasive ventilation and had preset do-not-intubate or comfort-measures-only orders. Data Extraction: Data abstraction followed Meta-analysis of Observational Studies in Epidemiology guidelines. Data quality was assessed using a modified Newcastle-Ottawa Scale. Data Synthesis: Twenty-seven studies evaluating 2,020 patients with do-not-intubate orders and three studies evaluating 200 patients with comfort-measures-only orders were included. In patients with do-not-intubate orders, the pooled survival was 56% (95% CI, 49–64%) at hospital discharge and 32% (95% CI, 21–45%) at 1 year. Hospital survival was 68% for chronic obstructive pulmonary disease, 68% for pulmonary edema, 41% for pneumonia, and 37% for patients with malignancy. Survival was comparable for patients treated in a hospital ward versus an ICU. Quality of life of survivors was not reduced compared with baseline, although few studies evaluated this. No studies evaluated quality of dying in nonsurvivors. In patients with comfort-measures-only orders, a single study showed that noninvasive ventilation was associated with mild reductions in dyspnea and opioid requirements. Conclusions: A large proportion of patients with do-not-intubate orders who received noninvasive ventilation survived to hospital discharge and at 1 year, with limited data showing no decrease in quality of life in survivors. Provision of noninvasive ventilation in a well-equipped hospital ward may be a viable alternative to the ICU for selected patients. Crucial questions regarding quality of life in survivors, quality of death in nonsurvivors, and the impact of noninvasive ventilation in patients with comfort-measures-only orders remain largely unanswered.