Journal of clinical monitoring and computing
-
J Clin Monit Comput · Aug 2004
Clinical TrialPresentation of laboratory and sonoclot variables using principal component analysis: identification of hypo- and hypercoagulation in the HELLP syndrome.
The HELLP (Hemolysis, Elevated Liver enzyme, and Low Platelet) syndrome requires close monitoring of rapid changes in hemostasis. A bedside viscoelastic test--Sonoclot--was used together with coagulation, liver and hemolysis laboratory analyses in three parturients with the HELLP syndrome up to 10 days postpartum. Principal component analysis (PCA) was used to reduce the dimensionality of this multivariate problem and to visualize this process in a two-dimensional plot. ⋯ The effects of emergency delivery, correction of low plasma-antithrombin with plasma and antithrombin factor concentrate, plasma exchange and individualized dosages of low molecular weight heparin to counteract postpartum Sonoclot detected hypercoagulation were evaluated. The efficiency of each treatment strategy was visualized in the PCA plot by movement towards an area with normocoagulation. In conclusion, PCA of viscoelastic and laboratory coagulation analysis data facilitated the detection of both hypo- and hypercoagulative events and represents an alternative way to evaluate treatment strategies in patients with complex coagulative disorders, like the HELLP syndrome.
-
J Clin Monit Comput · Aug 2004
Model-based prediction of expiratory resistance index in patients with asthma.
Develop a sensitive algorithm and index for detection of asthma patients using forced expiratory flow curves. ⋯ The estimated parameters were sensitive indicators of the degree of lung function impairment and were able to accurately distinguish between healthy and asthmatic patients.
-
J Clin Monit Comput · Aug 2004
The pulse in reflectance pulse oximetry: modeling and experimental studies.
Reflectance pulse oximetry permits the use of alternative monitoring sites such as the face or torso, and is the approach commonly employed in fetal pulse oximetry systems. The purpose of this study is to investigate the impact of assumptions about the nature of arterial pulsatility on the calibration of such systems. ⋯ The sensitivity of reflectance pulse oximetry calibration to the depth and magnitude of arterial pulsatility reinforces the observation that monitoring site selection is of importance in optimizing reflectance pulse oximetry performance, particularly fetal pulse oximetry. Sites with palpable pulsatility should be avoided.
-
J Clin Monit Comput · Aug 2004
Randomized Controlled Trial Comparative Study Clinical TrialThe effects of isoflurane and propofol on intraoperative neurophysiological monitoring during spinal surgery.
To compare the effects of isoflurane and propofol on intraoperative neurophysiological monitoring (IONM) during spinal surgery. ⋯ Isoflurane inhibited IONM more than propofol. Propofol is recommended for critical spinal surgery, particularly when motor pathway function is monitored.
-
J Clin Monit Comput · Aug 2004
Weaning from long-term mechanical ventilation: a nonpulmonary weaning index.
Despite the extensive investigations in the area of weaning, clinicians are still struggling with the question of when to begin the process of weaning. Clinical weaning indices designed to predict the weaning potential are most frequently based on pulmonary factors. However, many physiological, respiratory, and mechanical factors also have impact on weaning, but are often overlooked. We suggest a new "nonpulmonary weaning index" (NPWI), which assesses the influence of factors such as blood albumin and total blood protein on the weaning success. ⋯ The results of this study suggest that in the decision whether to attempt weaning from long-term mechanical ventilation, more attention should be paid to the nonpulmonary factors.