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
Wireless photoplethysmographic device for heart rate variability signal acquisition and analysis.
The photoplethysmographic (PPG) signal has the potential to aid in the acquisition and analysis of heart rate variability (HRV) signal: a non-invasive quantitative marker of the autonomic nervous system that could be used to assess cardiac health and other physiologic conditions. A low-power wireless PPG device was custom-developed to monitor, acquire and analyze the arterial pulse in the finger. The system consisted of an optical sensor to detect arterial pulse as variations in reflected light intensity, signal conditioning circuitry to process the reflected light signal, a microcontroller to control PPG signal acquisition, digitization and wireless transmission, a receiver to collect the transmitted digital data and convert them back to their analog representations. ⋯ Kubios was able to generate a report sheet with the time domain and frequency domain parameters of the acquired data. These features were then compared against those calculated by MATLAB. The preliminary results demonstrate that the prototype wireless device could be used to perform HRV signal acquisition and analysis.
-
Conf Proc IEEE Eng Med Biol Soc · Jan 2012
Stroke volume obtained from the brachial artery using transbrachial electrical bioimpedance velocimetry.
Stroke volume (SV) is the quantity of blood ejected by the cardiac ventricles per each contraction. When SV is multiplied by heart rate, cardiac output is the result. Cardiac output (CO), in conjunction with hemoglobin concentration and arterial oxygen saturation are the cornerstones of oxygen transport. ⋯ The technique involves passage of a constant magnitude, high frequency, and low amperage ac from the upper arm to the antecubital fossa. In all other respects, the operational aspects of TBEV are consistent with ICG. There is good evidence suggesting that the TBEV waveform and its derivatives are generated by blood resistivity changes only.
-
Conf Proc IEEE Eng Med Biol Soc · Jan 2012
Prediction of extubation failure for neonates with respiratory distress syndrome using the MIMIC-II clinical database.
Extubation failure (EF) is an ongoing problem in the neonatal intensive care unit (NICU). Nearly 25% of neonates fail their first extubation attempt, requiring re-intubations that are associated with risk factors and financial costs. ⋯ From an initial list of 57 candidate features, our machine learning approach narrowed down to six features useful for building an EF prediction model: monocyte cell count, rapid shallow breathing index, fraction of inspired oxygen (FiO(2)), heart rate, PaO(2)/FiO(2) ratio where PaO(2) is the partial pressure of oxygen in arterial blood, and work of breathing index. Algorithm performance had an area under the receiver operating characteristic curve (AUC) of 0.871 and sensitivity of 70.1% at 90% specificity.
-
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
Assessing traumatic brain injuries using EEG power spectral analysis and instantaneous phase.
Although mild traumatic brain injury (mTBI) occurs commonly, little is known about how multiple mTBI incidents accumulate over time to produce serious morbidity or how the extent of injury can be quantified. This work presents a rat model that uses deceleration-induced brain trauma and an implantable EEG system for recording injury-induced changes in brain activity. ⋯ We found that in different frequency bands, both EEG power spectra and the instantaneous phases of the two EEG channels before the impact were different from those measured after the impact. This study shows that EEG analysis can be used as a tool to identify and assess brain related injuries.