Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference
-
Conf Proc IEEE Eng Med Biol Soc · Jan 2012
An elementary analysis of physiologic shock and multi-organ failure: the autodigestion hypothesis.
Physiological shock and subsequent multi-organ failure is one of the most important medical problems from a mortality point of view. No agreement exists for mechanisms that lead to the relative rapid cell and organ failure during this process and no effective treatment. We postulate that the digestive enzymes synthesized in the pancreas and transported in the lumen of the small intestine as requirement of normal food digestion play a central role in multi-organ failure. ⋯ Entry of the digestive enzymes into the wall of the intestine precipitates an autodigestion process as well as an escape of pancreatic enzymes and breakdown products generated by them into the system circulation. The consequence of autodigestion is multiorgan failure. We discuss the possibility to block the digestive enzymes in acute forms of shock as a potential therapeutic intervention.
-
Conf Proc IEEE Eng Med Biol Soc · Jan 2012
Relaxofon: a neuromuscular blockade monitor for patients under general anesthesia.
Anesthesia consists of three components: unconsciousness, analgesia and neuromuscular blockade (NMB). A specific drug is administered by the anesthesiologist to control these different components. In this paper we propose a new system for monitoring the neuromuscular blockade in anesthesized patients during surgery. ⋯ Finally, we calculated the Pearson correlation coefficient to measure the linear dependence between the two methods. Automatic Train-of-Four ratio calculations using this system showed very good agreement with manual calculations. Results from this work may ultimately lead to integration of NMB monitoring to an automated closed-loop anesthesia system.
-
Conf Proc IEEE Eng Med Biol Soc · Jan 2012
An implantable neural stimulator for intraspinal microstimulation.
This paper reports on a wireless stimulator device for use in animal experiments as part of an ongoing investigation into intraspinal stimulation (ISMS) for restoration of walking in humans with spinal cord injury. The principle behind using ISMS is the activation of residual motor-control neural networks within the spinal cord ventral horn below the level of lesion following a spinal cord injury. The attractiveness to this technique is that a small number of electrodes can be used to induce bilateral walking patterns in the lower limbs. ⋯ Recent acute animal experiments have demonstrated the feasibility of using ISMS to produce the coordinated walking patterns. Here we described a wireless implantable stimulation system to be used in chronic animal experiments and for providing the basis for a system suitable for use in humans. Electrical operation of the wireless system is described, including a demonstration of reverse telemetry for monitoring the stimulating electrode voltages.
-
Conf Proc IEEE Eng Med Biol Soc · Jan 2012
A survival prediction model of rats in hemorrhagic shock using the random forest classifier.
Hemorrhagic shock is the cause of one third of deaths resulting from injury in the world. Although many studies have tried to diagnose hemorrhagic shock early and accurately, such attempts were inconclusive due to compensatory mechanisms of humans. The objective of this study was to construct a survival prediction model of rats in hemorrhagic shock using a random forest (RF) model, which is a newly emerged classifier acknowledged for its performance. ⋯ For the LR model, sensitivity, specificity, accuracy, and area under the receiver operating characteristic curve (ROC-AUC) were 1, 0.89, 0.94, and 0.98, respectively. For the RF models, sensitivity, specificity, accuracy, and AUC were 0.96, 1, 0.98, and 0.99, respectively. In conclusion, the RF model was superior to the LR model for survival prediction in the rat model.
-
Conf Proc IEEE Eng Med Biol Soc · Jan 2012
Effect of arching spine on deformation of the ligamentum flavum during epidural needle insertion.
When administering epidural anesthesia, anesthesiologists ask patients to arch their back. Arching the spine is thought to enlarge the gap between neighboring vertebral bones. The author hypothesized that tension inside the ligamentum flavum generated by arching the spine would reduce deformation of the ligamentum flavum during epidural needle insertion. ⋯ For the maximum reaction force the coefficient of variance decreased by dividing raw data with thickness of the ligamentum flavum, which meant that the maximum reaction force correlated with thickness of the ligamentum flavum. Less effect on deformation was observed. Hypothesis was correct in the porcine study, while the difference between the porcine and the patient's spine should be examined in the next research.