Treatment options may be limited for infants with obstructive sleep apnea when there is no surgically correctable upper airway lesion. We therefore evaluated, retrospectively, the efficacy of low-flow oxygen as a therapeutic option for infant obstructive sleep apnea. We reviewed the medical charts of 23 infants who had undergone a therapeutic trial of low-flow oxygen during polysomnography. Split-night polysomnography was used in 21/23 subjects while 2/23 had undergone two separate, full-night polysomnography sleep architecture and respiratory findings on the baseline polysomnogram segment that was obtained in room air were compared with the segment on low-flow oxygen (0.25–1 L/min). Wilcoxon signed rank or McNemar’s test were used as indicated for comparing apnea hypopnea index and measures of sleep architecture at baseline and with oxygen therapy. The mean (±SD) age of subjects was 4.8 (±2.7) months, with 52% being males. The median apnea hypopnea index fell from a baseline of 18 (range 7–43) to 3 (range 1–19; p = 0.001) on oxygen. The baseline median obstructive/mixed apnea index decreased from 2 (range 1–16) to 1 during oxygen therapy (range 0–1; p = 0.003). Additionally, a significant decrease in central apnea index (median interquartile range (IQR) 1 (0–2) vs. 0 (0–1), p = 0.002) was noted. Sleep efficiency remained unaffected, while O2 saturation (SaO2) average and SaO2 nadir improved on oxygen. We were able to confirm the utility of low-flow oxygen in reducing central, obstructive, and mixed apneas and improving average oxygen saturation in infants with obstructive sleep apnea (OSA).
Findings from the Implementation of a Validated Readmission Predictive Tool in the Discharge Workflow of a Medical Intensive Care Unit
Abstract Rationale Provider decisions about patients to be discharged from the intensive care unit (ICU) are often based on subjective intuition, sometimes leading to premature discharge and early readmission. The Stability and Work Load Index for Transfer (SWIFT) score, as a risk stratification tool, has moderate ability to predict patients at risk of ICU readmission. Objectives To describe findings following the incorporation of the SWIFT score into the discharge workflow of a medical ICU. Methods The study involved 5,293 consecutive patients discharged alive from the medical ICU of an academic medical center. The SWIFT score and associated percentage risk for readmission were incorporated into daily rounds for purpose of discharge decision-making. We measured readmission rates before and after implementation and observed changes in provider discharge decisions for individual patients after SWIFT discussions. Measurements and Main Results Baseline (n = 1,906) and implementation (n = 1,938) cohorts differed with respect to APACHE III scores (P = 0.03). In the implementation cohort, 26.2% of subjects had SWIFT scores greater than 15 and thus were predicted to have a higher risk of unplanned readmissions. In this high-risk group, 25% had SWIFT discussed in their discharge planning. There was modification of provider discharge decisions in 108 (30%) of cases in which the SWIFT was discussed. SWIFT score values above a prespecified cutoff of 15 were associated with physician tendency to prolong ICU stay or to discharge to a monitored setting (P < 0.001). There was no difference in 24-hour or 7-day readmission rates between the baseline and implementation cohorts (1.9 vs. 2.4%, P = 0.24; 6.5 vs. 7.4%, P = 0.26, respectively) even after adjustment for severity of illness. Conclusions Using the SWIFT score as an adjunct to clinical judgment, physicians modified their discharge decisions in one-third of subjects. Introducing such tools into the discharge workflow may present change management challenges that limit the evaluation of their impact on readmission rates and other relevant ICU outcomes.
Fresh Red Blood Cell Transfusion and Short-Term Pulmonary, Immunologic, and Coagulation Status: A Randomized Clinical Trial
Abstract Rationale Transfusion-related pulmonary complications are leading causes of morbidity and mortality attributed to transfusion. Observational studies suggest an important role for red blood cell (RBC) storage duration in these adverse outcomes. Objectives To evaluate the impact of RBC storage duration on short-term pulmonary function as well as immunologic and coagulation status in mechanically ventilated patients receiving RBC transfusion. Methods This is a double-blind, randomized, clinical trial comparing fresh (≤5 d of storage) versus standard issue single-unit RBC transfusion in adult intubated and mechanically ventilated patients. The primary outcome is the change in pulmonary gas exchange as assessed by the partial pressure of arterial oxygen to fraction of inspired oxygen concentration ratio (ΔPaO2/FiO2). Secondary outcomes include changes in immune and coagulation status. Measurements and Main Results Fifty patients were randomized to receive fresh RBCs and an additional 50 patients to standard issue RBCs. Median storage age was 4.0 days (interquartile range, 3.0–5.0) and 26.5 days (interquartile range, 21.0–36.0) in the fresh RBC group and standard issue RBC group, respectively. No differences were noted in the primary outcome of ΔPaO2/FiO2 (difference between the mean ΔPaO2/FiO2 in the standard issue RBC group vs. the fresh RBC group, –11.5; 95% confidence interval, −35.3 to 12.3; P = 0.22). Similarly, no significant differences were noted in markers of immunologic or coagulation status. Conclusions In this randomized clinical trial, no differences were noted in early measures of pulmonary function or in immunologic or coagulation status when comparing fresh versus standard issue single-unit RBC transfusion. Clinical trial registered with ClinicalTrials.gov (NCT00751322).
Derivation and Diagnostic Accuracy of the Surgical Lung Injury Prediction Model
Background Acute lung injury (ALI) is a serious postoperative complication with limited treatment options. A preoperative risk-prediction model would assist clinicians and scientists interested in ALI. The objective of this investigation was to develop a surgical lung injury prediction (SLIP) model to predict risk of postoperative ALI based on readily available preoperative risk factors. Methods Secondary analysis of a prospective cohort investigation including adult patients undergoing high-risk surgery. Preoperative risk factors for postoperative ALI were identified and evaluated for inclusion in the SLIP model. Multivariate logistic regression was used to develop the model. Model performance was assessed with the area under the receiver operating characteristic curve and the Hosmer-Lemeshow goodness-of-fit test. Results Out of 4,366 patients, 113 (2.6%) developed early postoperative ALI. Predictors of postoperative ALI in multivariate analysis that were maintained in the final SLIP model included high-risk cardiac, vascular, or thoracic surgery, diabetes mellitus, chronic obstructive pulmonary disease, gastroesophageal reflux disease, and alcohol abuse. The SLIP score distinguished patients who developed early postoperative ALI from those who did not with an area under the receiver operating characteristic curve (95% CI) of 0.82 (0.78-0.86). The model was well calibrated (Hosmer-Lemeshow, P = 0.55). Internal validation using 10-fold cross-validation noted minimal loss of diagnostic accuracy with a mean ± SD area under the receiver operating characteristic curve of 0.79 ± 0.08. Conclusions Using readily available preoperative risk factors, we developed the SLIP scoring system to predict risk of early postoperative ALI.
Timing of the Onset of Acute Respiratory Distress Syndrome: A Population-Based Study
BACKGROUND: Many patients with acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) have had recent healthcare interventions prior to developing ALI/ARDS. OBJECTIVE: To determine the timing of ALI/ARDS onset in relation to hospital admission and other healthcare interventions. METHODS: We conducted a population-based observational cohort study with a validated electronic surveillance tool, and identified patients with possible ALI/ARDS among critically ill adults at Mayo Clinic hospitals that provide critical care services for Olmsted County, Minnesota, in 2006. Trained investigators independently reviewed electronic medical records and confirmed the presence and timing of ALI/ARDS based on the American-European consensus definition. RESULTS: Of 124 episodes of ALI in 118 patients, only 5 did not fulfill the ARDS criteria. The syndrome developed a median 30 hours (IQR 10–82 h) after hospital admission in 79 patients (67%). ARDS was present on admission in 39 patients (33%), of whom 14 had recent hospitalization, 6 were transferred from nursing homes, and 3 had recent out-patient contact (1 antibiotic prescription, 1 surgical intervention, and 1 chemotherapy). Only 16 ARDS patients (14%) did not have known recent contact with a healthcare system. Compared to ARDS on admission, hospital-acquired ARDS was more likely to occur in surgery patients (54% vs 15%, P < .001), and had longer adjusted hospital stay (mean difference 8.9 d, 95% CI 0.3–17.4, P = .04). CONCLUSIONS: ARDS in the community most often develops either during hospitalization or in patients who recently had contact with a healthcare system. These findings have important implications for potential preventive strategies.
Alcohol Consumption and Development of Acute Respiratory Distress Syndrome: A Population-Based Study
This retrospective population-based study evaluated the effects of alcohol consumption on the development of acute respiratory distress syndrome (ARDS). Alcohol consumption was quantified based on patient and/or family provided information at the time of hospital admission. ARDS was defined according to American-European consensus conference (AECC). From 1,422 critically ill Olmsted county residents, 1,357 had information about alcohol use in their medical records, 77 (6%) of whom developed ARDS. A history of significant alcohol consumption (more than two drinks per day) was reported in 97 (7%) of patients. When adjusted for underlying ARDS risk factors (aspiration, chemotherapy, high-risk surgery, pancreatitis, sepsis, shock), smoking, cirrhosis and gender, history of significant alcohol consumption was associated with increased risk of ARDS development (odds ratio 2.9, 95% CI 1.3–6.2). This population-based study confirmed that excessive alcohol consumption is associated with higher risk of ARDS.