In reality, the complexities of optical plethysmography, along with their inherent noise, may preclude the utility of a simple relationship in a pulse oximeter that also displays PP. Filtering and straightforward signal-processing methods like least mean squares approximation and best uniform approximation will be needed to take this next step. Expert systems have appeared in […]
The discordance between the observed and derived respiratory rate is the focus of continued investigation. Lack of a “gold standard” in this aspect of the study limits further data analysis. Our research assistants were instructed to count the respiratory rate over 30 s and multiply by 2. This method may not have been sufficient, and […]
Like other vital signs, PP offers the opportunity to follow disease progression and the response to therapy. As a unique pathophysiologic vital sign, PP can also be used as a screening vital sign in patients with undifferentiated dyspnea. The rapid evaluation for PP in ED triage could drive the differentiation of subjective dyspnea in the […]
The greater number of patients who had been unnecessarily admitted to the hospital may reflect the conservative approach that many physicians have in the management of asthma. The alternate disposition indicated by AT-PP supports its inclusion as an adjunct tool in patient assessment. Relapsing patients who had been discharged from the hospital are comparatively less […]
Oximetry plethysmography also showed PP-like phenomena, which correspond to the BP measured PP events (Fig 4, top, A). A linear regression model describes a transfer function, which relates AT-PP in units of millimeters of Hg to a decrease in plethys-mographic amplitude (Fig 4, bottom, B). The slope of this relationship is roughly 0.01 V/mm Hg, […]
The interrater reliabilities, as assessed with intraclass correlation, are listed in Table 3. Neither the composite nor any of the subscales met our criterion for reliability (0.80). However, the estimated mean of the composite score did meet our criterion, as did the mean for OD at pretreatment. The mean total score, which was the only […]
The risk ratio was 5.32 for hospital admission among patients with PP, which exceeded this threshold. This is in contrast to the same analysis for the initial AT-PP measurement prior to standardized asthma treatment, in which the mean Wilcoxon AUC-ROC was 0.571 (95% CI, 0.27 to 0.87) [Fig 2, bottom, B, inset). The AT-PP threshold […]