Intubation Timing in COVID-19 Based on ROX Index and Association With Patient Outcomes.

BACKGROUND: Timing of intubation in COVID-19 is controversial. We sought to determine the association of the ROX (Respiratory rate-OXygenation) index defined as [Formula: see text] divided by [Formula: see text] divided by breathing frequency at the time of intubation with clinical outcomes. METHODS: We conducted a retrospective cohort study of patients with COVID-19 who were intubated by using a database composed of electronic health record data from patients with COVID-19 from 62 institutions. Multivariable logistic regression was used to evaluate the impact of ROX index score on mortality. We analyzed the ROX index as a continuous variable as well as a categorical variable by using cutoffs previously described as predicting success with high-flow nasal cannula. RESULTS: Of 1,087 subjects in the analysis group, the median age was 64 years, and more than half had diabetes; 55.2% died, 1.8% were discharged to hospice, 7.8% were discharged to home, 27.3% were discharged to another institution, and 7.8% had another disposition. Increasing age and a longer time from admission to intubation were associated with mortality. After adjusting for sex, race, age, comorbidities, and days from admission to intubation, an increasing ROX index score at the time of intubation was associated with a lower risk of death. In a logistic regression model, each increase in the ROX index score by 1 at the time of intubation was associated with an 8% reduction in odds of mortality (odds ratio 0.92, 95% CI 0.88-0.95). We also found an odds ratio for death of 0.62 (95% CI 0.47-0.81) for subjects with an ROX index score ≥ 4.88 at the time of intubation. CONCLUSIONS: Among a cohort of subjects with COVID-19 who were ultimately intubated, a higher ROX index at the time of intubation was positively associated with survival.

Use of therapeutic hypothermia in cocaine-induced cardiac arrest: further evidence.

Therapeutic hypothermia is an important and successful treatment that has been endorsed only in specific clinical settings of cardiac arrest. Inclusion criteria thus far have not embraced drug-induced cardiac arrest, but clinical evidence has been mounting that therapeutic hypothermia may be beneficial in such cases. A 59-year-old man who experienced a cocaine-induced cardiac arrest had a full neurological recovery after use of therapeutic hypothermia. The relevant pathophysiology of cocaine-induced cardiac arrest is reviewed, the mechanism and history of therapeutic hypothermia are discussed, and the clinical evidence recommending the use of therapeutic hypothermia in cocaine-induced cardiac arrest is reinforced.

A 20-year-old woman with rapidly progressive dyspnea and diffuse pulmonary infiltrates.

Silicone is a liquid polymer previously considered to be immunologically inert and favored in cosmetic procedures. Increasing evidence shows a multisystemic inflammatory reaction to its administration constituting the silicone embolism syndrome (SES). The majority of adverse effects are seen in the pulmonary system resulting in extensive diffuse alveolar damage and ultimately ARDS. Neurologic involvement occurs frequently and is uniformly fatal. Large volume injections, high pressure infiltrations and prior exposure to silicone have been implicated, with an IgG polydimethylsiloxane antibody described. Most patients meet Schonfield criteria for fat embolism syndrome and treatment is largely supportive. As the illicit use of injectable silicone rises worldwide, so does the incidence of related morbidities and fatalities, necessitating a high index of suspicion for SES in patients with neurologic or pulmonary symptoms and recent exposure to liquid silicone. We report an unusual case of multi-organ dysfunction following silicone injection.

A 65-year-old man with shortness of breath, pleuritic chest pain, and recurrent pneumonia.

Recurrent pulmonary infections are common among patients with chronic obstructive pulmonary disease. Imaging of the thorax beyond a routine chest radiograph, such as computed tomography imaging, should be considered for these patients. Fiberoptic bronchoscopy should also be considered for these patients, especially in cases in which respiratory cultures do not provide guidance for antibiotic therapy. The patient in the present case report experienced recurrent pneumonias despite adequate treatment with intravenous and oral antibiotics. He underwent computed tomography imaging of the thorax, which demonstrated a suspicious lesion in the left mainstem bronchus. This finding prompted a fiberoptic bronchoscopy, which revealed an endobronchial tumor. Given the patient's history of cigarette smoking, it was surprising to find that he had a benign endobronchial neurogenic tumor, which was removed in subsequent rigid bronchoscopy.

Rhythmic oscillations in the performance of a sustained attention task.

Attempts to sustain a narrow focus of attention over a long period of time are effortful and are punctuated by lapses. Most studies of sustained attention performance obscure the presence and pattern oflapses by reporting measures that are summed across the entire period of an individual's performance, or that are average scores for blocks of trials across many participants. In the present study we attempted to explore fluctuation in the attention of individual participants over the course of a vigilance task and to quantify its periodicity, if any exists. Normal university students listened to letters of the alphabet, arranged randomly and presented at a rate of 2 per second for 20 min. They were instructed to press a hand-held button when they detected a target two consecutive identical letters). Continuous estimates of performance accuracy (correctly detected targets) at regularly spaced time intervals were created for each participant using a moving time window. The resulting functions were analyzed in order to detect and quantify periodicity using a Fast Fourier Transform (FF). The most often observed rhythms for those participants with adequate FFT power congregated at 1-2 min, 4-7 min and greater than 10 min. Performance functions from 36 of the 40 subjects displayed at least two of these frequencies. Other studies have identified cycles in performance during similar vigilance challenges, but without particular rhythms or with no particular shared frequencies amongst participants. The possible sources of these fluctuations and the differences in the findings of these studies and the present study are discussed.

Measures of variations in performance during a sustained attention task.

In this study the authors developed and explored measures of short-term variations in accuracy on a test of sustained attention, a departure from traditional measures of average performance over long periods. The study participants were normal young adults, actively engaged in a continuous performance test (CPT). Both correct (hits) and incorrect (misses) responses to CPT targets appeared to aggregate in runs (2 or more consecutive hits or misses). Results of a Monte-Carlo procedure indicated that these runs were longer and fewer than would occur if hits and misses were randomly distributed. Average accuracy decreased between the first and second 5-min quarter of the test, then remained level. The length of hit runs followed the same pattern. However, other aspects of performance continued to change. The amount of time participants spent in miss runs began to increase significantly in the third quarter, and the frequency of miss runs did not increase until the fourth quarter. Explanations of these findings based upon changes in perceptual sensitivity or upon phasic increases in arousal caused by hits were rejected by further analysis. There was evidence that the length of miss runs was limited by a target-expectancy effect created by the specific parameters of our CPT. The authors conclude that measures of variations in performance reveal aspects of vigilance that are not tapped by traditional measures, and that factors that initiate, sustain and terminate both hit and miss runs are important targets of future research. Additional research is needed to determine whether or not the particular measures developed in this study may contribute to the understanding of attention problems in clinical populations.