Understanding Peripheral Blood Pressure Signals: A Statistical Learning Approach

Proper estimation of body fluid status for human or animal subjects has always been a challenging problem. Accurate and timely estimate of body fluid can prevent life threatening conditions under trauma and severe dehydration. The main objective of this research is the estimation, classification and detection of dehydration in human and animal subjects using peripheral blood pressure (PBP) signals. Peripheral venous pressure (PVP) and peripheral arterial pressure (PAP) signals have been investigated in this research. Both PVP and PAP signals are PBP signals. A dataset of PVP signals was collected using standard peripheral intravenous catheters from human subjects suffering from hypertrophic pyloric stenosis. Using this dataset, we successfully classified dehydrated subjects from hydrated subjects using regularized logistic regression on frequency domain data of the PVP signals. During the data acquisition process, the PVP signals was corrupted by noise and blood clot. So, we developed an unsupervised anomaly detection algorithm for PVP signals using hidden Markov model and Kalman filter. This anomaly detection algorithm removed the human bias in data-preprocessing. Another dataset of PAP and PVP signals was collected from pigs under anesthesia using the Millar catheter. We proposed a integral pulse frequency modulation (IPFM) based signal model for both PAP and PVP signals. The proposed model-synthesized signal is highly correlated with the experimental data. The model-synthesized signals also performs similar to experimental signals under classification tasks. We also examine the model estimated parameters both qualitatively and quantitatively. This model can also quantify the effect of respiratory rate on heart rate variability. Increasing doses of anesthesia has similar effect of getting hydrated from dehydration

Understanding Peripheral Blood Pressure Signals: A Statistical Learning Approach

Proper estimation of body fluid status for human or animal subjects has always been a challenging problem. Accurate and timely estimate of body fluid can prevent life threatening conditions under trauma and severe dehydration. The main objective of this research is the estimation, classification and detection of dehydration in human and animal subjects using peripheral blood pressure (PBP) signals. Peripheral venous pressure (PVP) and peripheral arterial pressure (PAP) signals have been investigated in this research. Both PVP and PAP signals are PBP signals. A dataset of PVP signals was collected using standard peripheral intravenous catheters from human subjects suffering from hypertrophic pyloric stenosis. Using this dataset, we successfully classified dehydrated subjects from hydrated subjects using regularized logistic regression on frequency domain data of the PVP signals. During the data acquisition process, the PVP signals was corrupted by noise and blood clot. So, we developed an unsupervised anomaly detection algorithm for PVP signals using hidden Markov model and Kalman filter. This anomaly detection algorithm removed the human bias in data-preprocessing. Another dataset of PAP and PVP signals was collected from pigs under anesthesia using the Millar catheter. We proposed a integral pulse frequency modulation (IPFM) based signal model for both PAP and PVP signals. The proposed model-synthesized signal is highly correlated with the experimental data. The model-synthesized signals also performs similar to experimental signals under classification tasks. We also examine the model estimated parameters both qualitatively and quantitatively. This model can also quantify the effect of respiratory rate on heart rate variability. Increasing doses of anesthesia has similar effect of getting hydrated from dehydration

Endoscopic findings in children with stridor.

SummaryCongenital and acquired airway diseases are responsible for upper respiratory distress and stridor in children. In neonatal intensive care units, we have seen increased survival in premature babies, but also a high incidence of airway complications related to intubation, which present as stridor.AimTo review endoscopic findings in children with stridor.Study designa cross-sectional cohort study.MethodsA retrospective analysis was done of 55 cases of children with stridor who underwent endoscopic exams, between January 1997 and December 2003.Results69% were aged below one year. The main indications for endoscopy were post-extubation stridor (63.63%) and evaluation of neonatal stridor (21.82%). Many associated diseases were seen, including lung diseases (60%), neurological condition (45.4%), and GERD (40%). The main endoscopic findings and indications for tracheotomy were subglottic stenosis (27.27%) and airway inflammatory process (21.82%) occurring in children under five years old. Congenital disorders were more frequent in children under age one year.ConclusionNeonatal stridor has many causes; those related to tracheal intubation are more frequent in hospitals that treat more complex diseases. Pediatricians and otorhinolaryngologists should know the main causes of stridor and perform detailed clinical evaluations to determine case severity. The endoscopic examination, must be meticulous

Severe airway obstruction in an infant with congenital tracheal stenosis and congenital heart disease -A case report-

Congenital tracheal stenosis (CTS), though rare, is important because the mortality and morbidity rates are high in infants. Especially, associated congenital heart disease (CHD) in these infants may compound the effects of airway pathology. A 3-week-old patient with long-segmental tracheal stenosis below an anomalous right-upper lobe (RUL) bronchus had undergone a total correction of double outlet right ventricle. On third postoperative day, hypercarbia developed, and severe airway obstruction and atelectasis were detected. An emergency slide tracheoplasty was performed under cardiopulmonary bypass (CPB). The patient recovered well after the surgery. Thus, special attention needs to be paid during the postoperative intensive care of patients with congenital tracheal anomalies. Early detection and prompt diagnosis of airway obstruction can help reduce the morbidity and mortality rates. Further, it is important to select the suitable treatment of CTS associated with CHD

An Educational Module Explaining the Utilization of Airway Ultrasonography as Standard of Care for Preoperative Airway Assessment

Background: One of the most life-threatening complications during anesthesia is an unrecognized difficult airway. Difficult airway patients are more prone to intraoperative complications including airway edema, periods of hypoxia, and trauma to the airway. Failure to oxygenate due to an unpredicted difficult airway can result in permanent organ damage. Standardizing the method in which providers classify airways preoperatively including handheld ultrasonography could help decrease the incidence of unpredicted difficult intubations. This quality improvement project assessed whether anesthesia providers would benefit from an educational module on ultrasound parameters to differentiate difficult versus easy intubations to increase ultrasound airway anatomy knowledge, skill, and predictive abilities. There were three participants, all are certified registered nurse anesthetists (CRNAs). The project involved a pretest, PowerPoint presentation, and posttest. Based on the results, an educational module on airway assessment utilizing ultrasound parameters compared to no ultrasound parameters increases knowledge in ultrasound airway anatomy, skill, and predictive ability in detecting a difficult versus easy intubation

Exploratory outlier detection for acceleromyographic neuromuscular monitoring : Machine learning approach

Funding Information: This research was funded by the Flanders Innovation and Entrepreneurship Fund, the Willy Gepts Fund for Scientific Research, and the Society for Anesthesia and Resuscitation of Belgium (SARB). Publisher Copyright: © Michaël Verdonck, Hugo Carvalho, Johan Berghmans, Patrice Forget, Jan Poelaert. Originally published in the Journal of Medical Internet Research (https://www.jmir.org), 06.06.2021. This is an open-access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work, first published in the Journal of Medical Internet Research, is properly cited. The complete bibliographic information, a link to the original publication on https://www.jmir.org/, as well as this copyright and license information must be included.Peer reviewedPublisher PD

Comparison of the clinical performance of the flexible laryngeal mask airway in pediatric patients under general anesthesia with or without a muscle relaxant: study protocol for a randomized controlled trial

Background The insertion of a laryngeal mask airway (LMA) is difficult in children due to the unique features of their airways. Muscle relaxants have been reported to facilitate LMA insertion in adults; however, there is a lack of evidence supporting this in children. This trial is designed to assess the feasibility of LMA insertion with and without the use of muscle relaxants in pediatric patients under general anesthesia. Methods/design This is a prospective, double-blind, single-center, parallel-arm, non-inferiority, randomized controlled trial to be conducted with participants aged 2–7 years who are undergoing elective ophthalmic surgery under general anesthesia. Participants are randomly assigned to one of two groups based on whether muscle relaxants are used (MR group, n = 64) or not used (Saline group, n = 64) prior to LMA insertion. The primary outcome is the oropharyngeal leak pressure (OLP) at a fixed gas flow of 3 L/min. The secondary outcomes are intubation time for successful insertion, ease of insertion and mask bagging, intubation attempt for successful insertion, successful insertion rate on the first attempt, fiberoptic view of the LMA position, postoperative complications, and changes in hemodynamic and ventilatory parameters. Discussion We will compare the OLPs to determine whether the muscle relaxant provides better conditions for the manipulation of the LMA. This is the first randomized controlled trial to investigate whether muscle relaxants are beneficial to the clinical performance of LMA insertion in pediatric patients under general anesthesia. This trial will be a resource for improving the process and safety of pediatric LMA insertion under general anesthesia. Trial registration ClinicalTrials.gov, NCT03487003. Registered on 18 April 2018.This work is supported by the grant of Research Institute of Medical Science, Daegu Catholic University (grant number; 201805)