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IEEE Reviews in Biomedical Engineering 2019With the invention of the electronic stethoscope and other similar recording and data logging devices, acoustic signal processing concepts and methods can now be applied... (Review)
Review
With the invention of the electronic stethoscope and other similar recording and data logging devices, acoustic signal processing concepts and methods can now be applied to bowel sounds. In this paper, the literature pertaining to acoustic signal processing for bowel sound analysis is reviewed and discussed. The paper outlines some of the fundamental approaches and machine learning principles that may be used in bowel sound analysis. The advances in signal processing techniques that have allowed useful information to be obtained from bowel sounds from a historical perspective are provided. The document specifically address the progress in bowel sound analysis, such as improved noise reduction, segmentation, signal enhancement, feature extraction, localization of sounds, and machine learning techniques. We have found that advanced acoustic signal processing incorporating novel machine learning methods and artificial intelligence can lead to better interpretation of acoustic information emanating from the bowel.
Topics: Acoustics; Artificial Intelligence; Auscultation; Digestive System Abnormalities; Humans; Intestines; Noise; Signal Processing, Computer-Assisted; Sound
PubMed: 30307875
DOI: 10.1109/RBME.2018.2874037 -
MedEdPORTAL : the Journal of Teaching... Oct 2019Cardiac auscultation skills are essential to the development of a competent physician. We created a hypothesis-driven cardiac auscultation laboratory session utilizing a...
INTRODUCTION
Cardiac auscultation skills are essential to the development of a competent physician. We created a hypothesis-driven cardiac auscultation laboratory session utilizing a high-fidelity simulator to teach these skills to second-year medical students at our institution. This program was grounded in deliberate practice opportunities to aid in the acquisition of cardiac auscultation skills.
METHODS
This session aimed to help students identify and discriminate between normal and pathologic heart sounds in the context of a clinical vignette. Faculty facilitators guided students through unknown patient cases and utilized the auscultation manikin to simulate corresponding heart sounds. Time was also allotted for students to auscultate the manikins and practice their cardiac physical examination skills.
RESULTS
This program has been in place at our institution since 2016 and has been well received by students and facilitators. Since its initial introduction in 2016, 183 second-year medical students have completed the cardiac auscultation lab session each year, for a total of 549 students. Evaluations of the session have improved as faculty have become more familiar with the mechanics of operating the auscultation manikin.
DISCUSSION
The cardiac exam and heart sounds lab can be adapted to any simulator model that is capable of producing heart sounds and can be done in a large- or small-group format. Enough time should be allotted to adequately work through all components of the laboratory. Student and faculty feedback has helped us further refine the session since its initial introduction to the curriculum.
Topics: Clinical Competence; Curriculum; Educational Measurement; Heart Auscultation; Heart Diseases; Heart Sounds; Humans; Manikins; Patient Simulation; Students, Medical
PubMed: 31976362
DOI: 10.15766/mep_2374-8265.10839 -
Journal of the Royal Society of Medicine Sep 1988
Topics: Cardiology; Echocardiography; Heart Auscultation; Heart Murmurs; Humans
PubMed: 3184104
DOI: 10.1177/014107688808100903 -
Sensors (Basel, Switzerland) Dec 2023Simple sensor-based procedures, including auscultation and electrocardiography (ECG), can facilitate early diagnosis of valvular diseases, resulting in timely treatment....
Simple sensor-based procedures, including auscultation and electrocardiography (ECG), can facilitate early diagnosis of valvular diseases, resulting in timely treatment. This study assessed the impact of combining these sensor-based procedures with machine learning on diagnosing valvular abnormalities and ventricular dysfunction. Data from auscultation at three distinct locations and 12-lead ECGs were collected from 1052 patients undergoing echocardiography. An independent cohort of 103 patients was used for clinical validation. These patients were screened for severe aortic stenosis (AS), severe mitral regurgitation (MR), and left ventricular dysfunction (LVD) with ejection fractions ≤ 40%. Optimal neural networks were identified by a fourfold cross-validation training process using heart sounds and various ECG leads, and their outputs were combined using a stacking technique. This composite sensor model had high diagnostic efficiency (area under the receiver operating characteristic curve (AUC) values: AS, 0.93; MR, 0.80; LVD, 0.75). Notably, the contribution of individual sensors to disease detection was found to be disease-specific, underscoring the synergistic potential of the sensor fusion approach. Thus, machine learning models that integrate auscultation and ECG can efficiently detect conditions typically diagnosed via imaging. Moreover, this study highlights the potential of multimodal artificial intelligence applications.
Topics: Humans; Artificial Intelligence; Auscultation; Electrocardiography; Neural Networks, Computer; Ventricular Dysfunction
PubMed: 38139680
DOI: 10.3390/s23249834 -
BioMed Research International 2020Cardiovascular diseases have become one of the most prevalent threats to human health throughout the world. As a noninvasive assistant diagnostic tool, the heart sound... (Review)
Review
Cardiovascular diseases have become one of the most prevalent threats to human health throughout the world. As a noninvasive assistant diagnostic tool, the heart sound detection techniques play an important role in the prediction of cardiovascular diseases. In this paper, the latest development of the computer-aided heart sound detection techniques over the last five years has been reviewed. There are mainly the following aspects: the theories of heart sounds and the relationship between heart sounds and cardiovascular diseases; the key technologies used in the processing and analysis of heart sound signals, including denoising, segmentation, feature extraction and classification; with emphasis, the applications of deep learning algorithm in heart sound processing. In the end, some areas for future research in computer-aided heart sound detection techniques are explored, hoping to provide reference to the prediction of cardiovascular diseases.
Topics: Algorithms; Cardiovascular Diseases; Deep Learning; Heart Auscultation; Heart Sounds; Humans; Signal Processing, Computer-Assisted
PubMed: 32420352
DOI: 10.1155/2020/5846191 -
Nature Reviews. Chemistry Feb 2023
Topics: Humans; Male; Fathers; Parenting; Auditory Perception; Auscultation
PubMed: 37117912
DOI: 10.1038/s41570-022-00459-6 -
Sensors (Basel, Switzerland) Jul 2021Conventional lung auscultation is essential in the management of respiratory diseases. However, detecting adventitious sounds outside medical facilities remains...
Conventional lung auscultation is essential in the management of respiratory diseases. However, detecting adventitious sounds outside medical facilities remains challenging. We assessed the feasibility of lung auscultation using the smartphone built-in microphone in real-world clinical practice. We recruited 134 patients (median[interquartile range] 16[11-22.25]y; 54% male; 31% cystic fibrosis, 29% other respiratory diseases, 28% asthma; 12% no respiratory diseases) at the Pediatrics and Pulmonology departments of a tertiary hospital. First, clinicians performed conventional auscultation with analog stethoscopes at 4 locations (trachea, right anterior chest, right and left lung bases), and documented any adventitious sounds. Then, smartphone auscultation was recorded twice in the same four locations. The recordings (n = 1060) were classified by two annotators. Seventy-three percent of recordings had quality (obtained in 92% of the participants), with the quality proportion being higher at the trachea (82%) and in the children's group (75%). Adventitious sounds were present in only 35% of the participants and 14% of the recordings, which may have contributed to the fair agreement between conventional and smartphone auscultation (85%; k = 0.35(95% CI 0.26-0.44)). Our results show that smartphone auscultation was feasible, but further investigation is required to improve its agreement with conventional auscultation.
Topics: Auscultation; Child; Feasibility Studies; Female; Humans; Lung; Male; Respiratory Sounds; Smartphone
PubMed: 34300670
DOI: 10.3390/s21144931 -
Medicina (Kaunas, Lithuania) Apr 2019As the prevalence of obesity is increasing in a population, diagnostics becomes more problematic. Our aim was to compare the 3M Littmann 3200 Electronic Stethoscope and... (Comparative Study)
Comparative Study
As the prevalence of obesity is increasing in a population, diagnostics becomes more problematic. Our aim was to compare the 3M Littmann 3200 Electronic Stethoscope and 3M Littman Cardiology III Mechanical Stethoscope in the auscultation of obese patients. . A total of 30 patients with body mass index >30 kg/m² were auscultated by a cardiologist and a resident physician: 15 patients by one cardiologist and one resident and 15 patients by another cardiologist and resident using both stethoscopes. In total, 960 auscultation data points were verified by an echocardiogram. Sensitivity and specificity data were calculated. Sensitivity for regurgitation with valves combined was higher when the electronic stethoscope was used by the cardiologist (60.0% vs. 40.9%, = 0.0002) and the resident physician (62.1% vs. 51.5%, = 0.016); this was also the same when stenoses were added (59.4% vs. 40.6%, = 0.0002, and 60.9% vs. 50.7%, = 0.016, respectively). For any lesion, there were no significant differences in specificity between the electronic and acoustic stethoscopes for the cardiologist (92.4% vs. 94.2%) and the resident physician (93.6% vs. 94.7%). The detailed analysis by valve showed one significant difference in regurgitation at the mitral valve for the cardiologist (80.0% vs. 56.0%, = 0.031). No significant difference in specificity between the stethoscopes was found when all lesions, valves and both physicians were combined (93.0% vs. 94.4%, = 0.30), but the electronic stethoscope had higher sensitivity than the acoustic (60.1% vs. 45.7%, < 0.0001). The analysis when severity of the abnormality was considered confirmed these results. There is an indication of increased sensitivity using the electronic stethoscope. Specificity was high using the electronic and acoustic stethoscope.
Topics: Age Factors; Aged; Aged, 80 and over; Body Mass Index; Cardiologists; Echocardiography; Female; Hearing Loss, High-Frequency; Heart Auscultation; Heart Murmurs; Humans; Male; Middle Aged; Obesity; Sensitivity and Specificity; Stethoscopes
PubMed: 30959832
DOI: 10.3390/medicina55040094 -
The Cochrane Database of Systematic... Feb 2017The goal of fetal monitoring in labour is the early detection of a hypoxic baby. There are a variety of tools and methods available for intermittent auscultation (IA) of... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The goal of fetal monitoring in labour is the early detection of a hypoxic baby. There are a variety of tools and methods available for intermittent auscultation (IA) of the fetal heart rate (FHR). Low- and middle-income countries usually have only access to a Pinard/Laënnec or the use of a hand-held Doppler device. Currently, there is no robust evidence to guide clinical practice on the most effective IA tool to use, timing intervals and length of listening to the fetal heart for women during established labour.
OBJECTIVES
To evaluate the effectiveness of different tools for IA of the fetal heart rate during labour including frequency and duration of auscultation.
SEARCH METHODS
We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (19 September 2016), contacted experts and searched reference lists of retrieved articles.
SELECTION CRITERIA
All published and unpublished randomised controlled trials (RCTs) or cluster-RCTs comparing different tools and methods used for intermittent fetal auscultation during labour for fetal and maternal well-being. Quasi-RCTs, and cross-over designs were not eligible for inclusion.
DATA COLLECTION AND ANALYSIS
All review authors independently assessed eligibility, extracted data and assessed risk of bias for each trial. Data were checked for accuracy.
MAIN RESULTS
We included three studies (6241 women and 6241 babies), but only two studies are included in the meta-analyses (3242 women and 3242 babies). Both were judged as high risk for performance bias due to the inability to blind the participants and healthcare providers to the interventions. Evidence was graded as moderate to very low quality; the main reasons for downgrading were study design limitations and imprecision of effect estimates. Intermittent Electronic Fetal Monitoring (EFM) using Cardiotocography (CTG) with routine Pinard (one trial)There was no clear difference between groups in low Apgar scores at five minutes (reported as < six at five minutes after birth) (risk ratio (RR) 0.66, 95% confidence interval (CI) 0.24 to 1.83, 633 babies, very low-quality evidence). There were no clear differences for perinatal mortality (RR 0.88, 95% CI 0.34 to 2.25; 633 infants, very low-quality evidence). Neonatal seizures were reduced in the EFM group (RR 0.05, 95% CI 0.00 to 0.89; 633 infants, very low-quality evidence). Other important infant outcomes were not reported: mortality or serious morbidity (composite outcome), cerebral palsy or neurosensory disability. For maternal outcomes, women allocated to intermittent electronic fetal monitoring (EFM) (CTG) had higher rates of caesarean section for fetal distress (RR 2.92, 95% CI 1.78 to 4.80, 633 women, moderate-quality evidence) compared with women allocated to routine Pinard. There was no clear difference between groups in instrumental vaginal births (RR 1.46, 95% CI 0.86 to 2.49, low-quality evidence). Other outcomes were not reported (maternal mortality, instrumental vaginal birth for fetal distress and or acidosis, analgesia in labour, mobility or restriction during labour, and postnatal depression). Doppler ultrasonography with routine Pinard (two trials)There was no clear difference between groups in Apgar scores < seven at five minutes after birth (reported as < six in one of the trials) (average RR 0.76, 95% CI 0.20 to 2.87; two trials, 2598 babies, I = 72%, very low-quality evidence); there was high heterogeneity for this outcome. There was no clear difference between groups for perinatal mortality (RR 0.69, 95% CI 0.09 to 5.40; 2597 infants, two studies, very low-quality evidence), or neonatal seizures (RR 0.05, 95% CI 0.00 to 0.91; 627 infants, one study, very low-quality evidence). Other important infant outcomes were not reported (cord blood acidosis, composite of mortality and serious morbidity, cerebral palsy, neurosensory disability). Only one study reported maternal outcomes. Women allocated to Doppler ultrasonography had higher rates of caesarean section for fetal distress compared with those allocated to routine Pinard (RR 2.71, 95% CI 1.64 to 4.48, 627 women, moderate-quality evidence). There was no clear difference in instrumental vaginal births between groups (RR 1.35, 95% CI 0.78 to 2.32, 627 women, low-quality evidence). Other maternal outcomes were not reported. Intensive Pinard versus routine Pinard (one trial)One trial compared intensive Pinard (a research midwife following the protocol in a one-to-one care situation) with routine Pinard (as per protocol but midwife may be caring for more than one woman in labour). There was no clear difference between groups in low Apgar score (reported as < six this trial) (RR 0.90, 95% CI 0.35 to 2.31, 625 babies, very low-quality evidence). There were also no clear differences identified for perinatal mortality (RR 0.56, 95% CI 0.19 to 1.67; 625 infants, very low-quality evidence), or neonatal seizures (RR 0.68, 95% CI 0.24 to 1.88, 625 infants, very low-quality evidence)). Other infant outcomes were not reported. For maternal outcomes, there were no clear differences between groups for caesarean section or instrumental delivery (RR 0.70, 95% CI 0.35 to 1.38, and RR 1.21, 95% CI 0.69 to 2.11, respectively, 625 women, both low-quality evidence)) Other outcomes were not reported.
AUTHORS' CONCLUSIONS
Using a hand-held (battery and wind-up) Doppler and intermittent CTG with an abdominal transducer without paper tracing for IA in labour was associated with an increase in caesarean sections due to fetal distress. There was no clear difference in neonatal outcomes (low Apgar scores at five minutes after birth, neonatal seizures or perinatal mortality). Long-term outcomes for the baby (including neurodevelopmental disability and cerebral palsy) were not reported. The quality of the evidence was assessed as moderate to very low and several important outcomes were not reported which means that uncertainty remains regarding the use of IA of FHR in labour.As intermittent CTG and Doppler were associated with higher rates of caesarean sections compared with routine Pinard monitoring, women, health practitioners and policy makers need to consider these results in the absence of evidence of short- and long-term benefits for the mother or baby.Large high-quality randomised trials, particularly in low-income settings, are needed. Trials should assess both short- and long-term health outcomes, comparing different monitoring tools and timing for IA.
Topics: Auscultation; Cardiotocography; Cesarean Section; Female; Fetal Distress; Heart Rate, Fetal; Humans; Infant, Newborn; Infant, Newborn, Diseases; Labor, Obstetric; Perinatal Mortality; Pregnancy; Seizures; Ultrasonography, Doppler
PubMed: 28191626
DOI: 10.1002/14651858.CD008680.pub2 -
Heart (British Cardiac Society) Jan 2019We aimed to determine if auscultation or a point-of-care scan could reduce the need for standard echocardiography (transthoracic echocardiogram (TTE)) in community...
OBJECTIVES
We aimed to determine if auscultation or a point-of-care scan could reduce the need for standard echocardiography (transthoracic echocardiogram (TTE)) in community patients with asymptomatic murmurs.
METHODS
Requests from general practitioners were directed to a new murmur clinic. Auscultation and a point-of-care scan were performed by a cardiologist between 1 October 2013 and 31 December 2014 and by a scientist between 21 July 2015 and 9 May 2017.
RESULTS
In the first phase (cardiologist), there were 75 patients, mean age 54 (56 women), and in the second phase there were 100 patients, mean age 60 (76 women). In the total population of 175, abnormalities were shown on TTE in 52 (30%), on point-of-care scan in 52 (30%) and predicted on auscultation in 45 (26%) (p=0.125; 95% CI -0.02 to 0.29). The sensitivity of auscultation was not significantly different for the cardiologist (91%) as for the scientist (83%) (p=0.18; 95% CI -0.22 to 0.175) and the specificity was 100% for both. Accuracy was 97% for the cardiologist and 95% for the scientist. For the point-of-care scan, the sensitivity, specificity, positive and negative predictive values and accuracy were 100% for both cardiologist and scientist.
CONCLUSION
Most patients in a specialist murmur clinic had normal auscultation and point-of-care scans and no additional valve disease was detected by standard echocardiography. This suggests that a murmur clinic is a valid model for reducing demand on hospital echocardiography services.
Topics: Echocardiography; Female; Heart Auscultation; Heart Murmurs; Heart Valve Diseases; Humans; Male; Medical Overuse; Middle Aged; Point-of-Care Testing; Predictive Value of Tests; Reproducibility of Results; Sensitivity and Specificity; United Kingdom
PubMed: 30049836
DOI: 10.1136/heartjnl-2018-313393