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At least 649 records · Page 36Linked to original sources
PubMed1999

Cardiopulmonary auscultation: duo for strings--Opus 99.

In spite of increasing mechanization in medicine and reliance on "high-tech" diagnostic tools, bedside clinical skills of the attending physician can still identify findings that are missed by the more sophisticated devices. Using a stethoscope, we relied on our skills in inspection, palpation, percussion, auscultation, as well as echocardiography and phonocardiography to diagnose a patient whose murmur was very reminiscent of the D-sharp pizzicato in the Cello Sonata in F, Opus 99, by Johannes Brahms. Initial echocardiography was not helpful. We suspected an anomalous chorda and confirmed this with phonocardiography and a second echocardiography. Although advances in cardiac imaging are extremely helpful, the use of simple clinical skills, in addition to being fun, is not obsolete. Cardiopulmonary auscultation should receive more emphasis in the medical school curriculum and clinical training.

Autopsy↗
PubMed1999

Sesquicentennial of the ophthalmoscope.

The year 2000 coincides with the 150th anniversary of the invention of the ophthalmoscope. In 1850, Hermann von Helmholtz (1821-1894) inaugurated the modern era in ophthalmology with his magnificent instrument, which has done more to revolutionize the development of ophthalmology than any other invention or discovery. Before Helmholtz's invention, it was not possible to visualize the posterior pole of the eye in a living subject. The ophthalmoscope permitted the clinical correlation of signs and symptoms with findings in the retina, vitreous, and optic nerve. The ophthalmoscope became the model for all forms of endoscopy that followed. It is often compared in importance with 2 earlier inventions, the telescope (17th century) and the stethoscope (early 19th century). All of these instruments made dramatic new information available to the human mind.

Germany↗
PubMed1987

Duplex B-mode imaging for the diagnosis of deep venous thrombosis.

Real-time B-mode venous imaging has numerous advantages for the diagnosis of acute deep venous thrombosis (DVT). During the 11 months ending Feb 1, 1986, we examined 431 patients for possible acute DVT using a 5-MHz hand-held continuous wave Doppler stethoscope and a duplex real-time B-mode imager. Clots were seen in 86 patients in multiple views and cross sections. Normal veins completely collapsed with probe pressure on the skin. Blood flow was seen and heard, and abnormal flow was detected. There were no false-negatives (100% sensitivity). Early in the study, two false-positives occurred (78% specificity), but these errors will not recur. These tests are accurate, noninvasive, and inexpensive. They differentiate acute from chronic thrombosis and are repeatable. Duplex imaging may become the "gold standard" for the diagnosis of DVT.

Diagnostic Errors↗
PubMed1997

An assessment of blood pressure measurement in a diabetic clinic using random-zero, semi-automated, and 24-hour monitoring.

We have undertaken a randomized, observer-blinded comparison of three different methods of assessing blood pressure in 40 outpatients with hypertension complicating diabetes mellitus: the Hawksley random zero sphygmomanometer (RZS) by two observers using a dual headed stethoscope; the semi-automated Dinamap monitor, and 24-h ambulatory blood pressure monitoring (ABPM) using a Spacelabs 90207. The techniques were compared by plotting the difference against average of readings obtained by combinations of two techniques (RZS observer 1 vs 2; RZS (mean observer 1 and 2) vs Dinamap; RZS (mean observer 1 and 2) vs daytime ABPM; and Dinamap vs daytime ABPM). There was good agreement of readings with RZS, observers 1 and 2 and RZS with Dinamap and daytime ABPM. When the three methods were used to classify blood pressure control according to BDA criteria, it was found that they produced equivalent results and although mean systolic pressures appeared lower with ABPM this did not reach statistical significance. Overall control of systolic blood pressure was classified as unsatisfactory in 82% of patients, diastolic blood pressure was unsatisfactory in 55%. Fifty-five percent were determined to be nocturnal 'non-dippers' by ABPM. They were older: median age 62.9 (range 35.9-83.5) years compared to 48.2 (32.4-70.0) years for 'dippers' (p<0.05). Thirteen of the 18 patients who did dip overnight had creatinines within the normal laboratory range, whereas only 6 of 22 'non-dippers' had normal creatinines (median 91 (56-768) micromol l(-1) for 'dippers' vs 166 (76-479) micromol l(-1) for 'non-dippers', p < 0.001). Nineteen of the 29 males studied were 'non-dippers' compared with only 4 out of 11 females (p < 0.001). There was no association between dipper status, duration or type of diabetes or presence of proteinuria.

Adult↗
PubMed1981

Measurement of tinnitus in humans.

Little quantitative measurement of tinnitus was possible before the development of the electric audiometer. Since then many ingenious attempts have been made to simulate the phenomenon. Frequency and masking measurements were described first in 1931 by E. M. Josephson and also by R. L. Wegel, and techniques involving loudness balance, free-field matching and taped sound effects have also been used. More accurate measurement of frequency content can be made by means of music synthesizer. A tinnitus measurement protocol should include assessment of: (1) frequency content; (2) loudness; (3) masking characteristics; and (4) objective measurements. Loudness measurements relate to the annoyance caused by the symptom, which depends, too, on the patient's personality and disposition. Masking characteristics also relate to the loudness of tinnitus and give additional guidance about the suitability of making therapy. They are repeatable and easy to perform. Objective measurements, whether performed with a stethoscope or intrameatal microphone, may reveal vascular bruits or cochlear emissions. We must wait to see how representative are the newer objective measurements of the subjective complaint.

Acoustic Stimulation↗
PubMed1990

A new cardiac auscultation simulator.

We have successfully developed a new cardiac auscultation simulator by applying recently developed digital and computer technology, which digitally records, stores, modifies, and plays back heart sounds and murmurs characteristic of various heart diseases. The simulator is capable of playing back different heart sounds or murmurs at each auscultatory site (aortic, pulmonic, tricuspid, and mitral) of a human chest-sized mannequin (made of urethane foam), through four built-in speakers. We were able to listen to accurate reproductions of heart sounds and murmurs at the same timing as in real patients by any type of stethoscope used in routine medical practice. This compact and portable educational apparatus, which simulates realistic auscultatory sounds, will impact greatly on the medical training of cardiac auscultation for physicians, medical students, nurses, and paramedicals.

Computer Simulation↗
PubMed1992

Accuracy and analysis of ambulatory blood pressure monitoring data.

Two devices used to record blood pressure, the ambulatory blood pressure monitoring recorder and standard stethoscope and mercury column, were tested for accuracy against the direct intra-arterial blood pressure of patients at rest and during exercise. Recorders were found to be as accurate as mercury column measurement in patients at rest. A number of assessment techniques of ambulatory data are reviewed, including: calculation of mean or median pressures, assessment of blood pressure load, and integration of the area under the blood pressure curve over time. These have been applied during the daytime and nighttime hours. Blood pressure load and area under the blood pressure curve, using different threshold criteria for nighttime and daytime, are recommended because of their potentially closer relation to target-organ disease of hypertension than are office blood pressure readings.

Ambulatory Care↗
PubMed2006

The cervical bruit: sound spectral analysis related to severity of carotid arterial disease.

Cervical bruits may signal the presence of high-grade narrowing of arterial supply to the brain. Previous small studies have suggested that severe arterial stenosis may produce bruits that persist longer and contain a greater proportion of higher-frequency sound spectral components. This study included 96 patients referred for duplex/Doppler testing after cervical bruits had been detected. With the use of a stethoscope equipped with wireless communication to an ordinary hand-held computer, we recorded these bruits, analyzed peak sound frequencies and the durations of sound persistence > or = 200 Hz, and correlated them with Doppler velocities. Overall, the durations and peak frequencies within the bruits correlated significantly with the peak Doppler derived velocities, that is, severity of arterial obstruction. In the presence of high-grade arterial stenosis (peak Doppler velocity > or = 200 cm/s), bruits regularly possessed either high peak frequencies or prolonged signal durations with a sensitivity approaching 90%. Bruits containing lower and nonsustained peak frequencies were uncommonly associated with severe arterial obstruction. Only well-transmitted bruits with frequencies reaching 200 Hz could be analyzed satisfactorily. In conclusion, we confirm earlier observations that peak frequencies and duration of arterial bruits correlate significantly with severity of underlying arterial obstruction. Equipment used is inexpensive, convenient, and portable. This method provides an objective means for confirming and quantifying subjective auditory impressions of bruits gained at the bedside. It can provide assistance in selecting patients for further testing and as a means for serial follow-up of individuals with known disease.

Brain↗
PubMedDate not supplied

Sonographically guided arterial blood sampling using a handheld Doppler device.

The purpose of this study was to evaluate the efficacy of a commercially available handheld Doppler device for sonographic guidance during arterial blood sampling in patients whose veins are inaccessible and whose arterial pulses are indistinct on palpation. From September 2000 through February 2001, blood samples were obtained from the brachial arteries of 20 patients ranging in age from 60 to 85 years. A commercially available continuous-wave, handheld Versadopp 10 Doppler device with a 10-MHz transducer, connected to a stethoscope, was aligned over each patient's brachial artery and used to determine the point of maximum flow. The blood-collection needle was inserted into the skin and advanced toward the point of maximum flow. Arterial blood samples were successfully obtained with no more than 2 passes in each patient. Sampling was unsuccessful in 2 patients; blood was obtained, however, from the contralateral brachial artery in both patients. This Doppler tool is convenient and easy to use and is helpful for obtaining arterial blood samples from obese or edematous patients whose veins cannot be accessed and who have weak, indistinct arterial pulses.

Aged↗
PubMed1982

Measurement of left ventricular ejection fraction with ionic 113mIn and a cardiac probe.

Left ventricular ejection fraction (LVEF) was measured with a cardiac probe (Nuclear Stethoscope, Bios Inc., Valhalla, New York) and 113mIn in 28 normal subjects and 86 patients with coronary artery disease (CAD). In 20 normal subjects 99mTC-RBCs were compared with 113mIn which binds to transferrin after IV injection. With 99mTc-RBCs, average LVEF was 57 +/- 7% (1 SD); with 113mIn, average LVEF was 55 +/- 8% (N.S.). Sequential measurements at different times over 60 min revealed good reproducibility. Comparison of LVEFs obtained using 99mTc-RBCs with a gamma camera and cardiac probe revealed a good correlation. The correlation coefficients were 0.92 in 25 patients with CAD and 0.95 in 10 patients with LV wall motion abnormalities. The LVEF obtained using a cardiac probe and 113mIn increased in 28 normals from 57 +/- 9% to 64 +/- 13% (P less than 0.001) during handgrip exercise, while the LVEF decreased from 45 +/- 9% to 41 +/- 10% (P less than 0.01) in patients with acute myocardial infarction 4-7 weeks after episode, from 48 +/- 11 to 40 +/- 12% (P less than 0.001) in patients with old myocardial infarction, and from 52 +/- 9 to 42 +/- 9% (P less than 0.001) in patients with angina pectoris. The cardiac probe and 113mIn provide a useful alternate means of determining left ventricular dysfunction in facilities where 99mTc and a gamma camera computer system are not readily available.

Cardiac Output↗
PubMed1995

Using cervical auscultation in the clinical dysphagia examination in long-term care.

The ability of the clinical dysphagia examination to identify patients who aspirate and to determine specialized diet management has been suspect. In long-term care, however, the clinical examination can be the only assessment procedure available to clinicians. Cervical auscultation with stethoscope was incorporated into the clinical examination for dysphagia in an attempt to enhance the clinical examination's ability to detect aspiration and to determine specialized diet management in long-term care. Comparison of the clinical examination's results with results from videofluoroscopy revealed significant agreement in both areas. Results support the use of cervical auscultation as a highly sensitive and specific method of dysphagia assessment in long-term care.

Adult↗
PubMed1988

Bowel sound biofeedback as a treatment for irritable bowel syndrome.

Using an electronic stethoscope placed on subjects' abdomens, bowel sound biofeedback was administered to five subjects suffering from irritable bowel syndrome (functional diarrhea). They were instructed to alternately increase and decrease colonic sounds in an attempt to gain control over bowel activity. Using daily ratings of diarrhea as the primary dependent measure, three of five subjects reduced mean ratings enough at posttreatment to meet our 50% criterion for success (100%, 94%, and 54%). At 1-year follow-up, two of the three short-term successes had maintained their level of improvement--each had ratings 75% below those of pretreatment.

Adult↗
PubMed1986

[Experiences up to now with diagnosis and microsurgical revascularization in disorders of erection].

Nine patients with impaired erection and a mean age of 41 years were diagnosed by means of a battery of multidisciplinary examinations: specific anamnesis, urological, neurological, endocrinological, angiological, psychosomatic and metabolic investigations, electromyography, measurement of the latency period and duration of the bulbocavernosus reflex, measurement of the nocturnal penis tumescence, penile blood-pressure index (PBPI), artificial erection with papaverine, flowmetry, phalloarteriography, dynamic cavernosonography. In all cases, an arterial and/or venous genesis was discovered as well as neurological or psychological factors. Three microsurgical techniques were employed: the end-to-side anastomosis of the A. epigastrica inferior preferably with the A. dorsalis penis (two cases), with the V. dorsalis penis profunda (four cases) and with the two combined (three cases). In the last cases, the vein was ligated or constricted proximal to the anastomosis. The primary factor in choosing the particular reconstruction method was the angiogram. Diagnosis entailed no complications for the patients. In addition to minor postoperative complications such as a hematoma, scar pains or hypervascularization of the glans and the corpus spongiosum, three early occlusions occurred in reconstructions up to one month postoperatively. One to five months after surgery the erectile potency had improved or normalized in seven out of nine patients, making intercourse possible. Two patients, the only two with a posttraumatic interruption in the bulbocavernosus reflex curve, showed no change. For purposes of postoperative control of arterio-venous anastomoses, the typical shunt sound is observed by stethoscope. After revascularization of the A. dorsalis penis, it is recommended that the PBPI be taken at the Aa. profundae penis and, when necessary, that a control angiography be performed. For the treatment of potency disturbances stemming from vascular causes, our results advocate that microsurgical vascular reconstruction be given due consideration before implantation of a penile prosthesis.

Adult↗
PubMed1992

The susceptibility of thermistor-based esophageal temperature probes to errors caused by electrically conductive fluids ("artificial saliva").

Several brands of esophageal stethoscopes with thermistor-based thermometers were tested to determine the susceptibility of the probe connector to contamination by oral secretions. A solution of half normal saline and 1% carboxy-methyl-cellulose was used to model the conductivity and viscosity of saliva. When 1 ml of test solution was allowed to track down the probe wires to the connector, several brands of thermistors gave erroneously elevated readings. The mean changes in temperature according to brand of thermistor were as follows: Electromedics, 0.1 +/- 0.1 degree C; Mallinckrodt, 1.7 +/- 0.8 degrees C; Respiratory Products, 0.1 +/- 0.2 degrees C; Sheridan, 3.6 +/- 1.9 degrees C; Vital Signs, 4.8 +/- 1.3 degrees C (peak) and 1.4 +/- 1.6 degrees C (final); and Yellow Springs, 0.9 +/- 0.4 degrees C. The manufacturers of the probes susceptible to this type of error should implement the appropriate design modifications. In the meantime, clinicians should be aware of this problem and may choose to prevent these errors by wrapping the connection with waterproof tape.

Auscultation↗
PubMed1988

Anesthetic mishaps and the cost of monitoring: a proposed standard for monitoring equipment.

Review of insurance data indicates that approximately 1.5 claims are paid per 10,000 anesthetic procedures, a conservative estimate of the incidence of preventable serious injury associated with anesthesia. Insurance data permit estimation of the premium cost for the anesthesiologist and hospital, per operating room per year, of $69,429.00. We propose the use of an enhanced monitoring standard requiring a pulse oximeter, capnograph, spirometer, halometer, automatic sphygmomanometer, breathing circuit oxygen analyzer, stethoscope, electrocardiographic monitor, and temperature monitor. We suggest that this premium cost, together with the estimate that 50% of incidents would be avoided, predicts a resultant saving of over $27,000/operating room/year, a savings equal to the entire cost of the enhanced monitoring system in approximately 8 months, or a yearly savings of over five times the annualized expense of the monitoring system. Thus, in addition to the moral imperative to monitor a patient during anesthesia to avoid injury and death, there is an economic incentive to monitor effectively.

Anesthesia↗
PubMed2004

Detection of the third heart sound using a tailored wavelet approach.

The third heart sound is normally heard during auscultation of younger individuals but disappears with increasing age. However, this sound can appear in patients with heart failure and is thus of potential diagnostic use in these patients. Auscultation of the heart involves a high degree of subjectivity. Furthermore, the third heart sound has low amplitude and a low-frequency content compared with the first and second heart sounds, which makes it difficult for the human ear to detect this sound. It is our belief that it would be of great help to the physician to receive computer-based support through an intelligent stethoscope, to determine whether a third heart sound is present or not. A precise, accurate and low-cost instrument of this kind would potentially provide objective means for the detection of early heart failure, and could even be used in primary health care. In the first step, phonocardiograms from ten children, all known to have a third heart sound, were analysed, to provide knowledge about the sound features without interference from pathological sounds. Using this knowledge, a tailored wavelet analysis procedure was developed to identify the third heart sound automatically, a technique that was shown to be superior to Fourier transform techniques. In the second step, the method was applied to phonocardiograms from heart patients known to have heart failure. The features of the third heart sound in children and of that in patients were shown to be similar. This resulted in a method for the automatic detection of third heart sounds. The method was able to detect third heart sounds effectively (90%), with a low false detection rate (3.7%), which supports its clinical use. The detection rate was almost equal in both the children and patient groups. The method is therefore capable of detecting, not only distinct and clearly visible/audible third heart sounds found in children, but also third heart sounds in phonocardiograms from patients suffering from heart failure.

Adolescent↗
PubMed2005

Diagnosing aortic valve stenosis by correlation analysis of wavelet filtered heart sounds.

Traditional auscultation performed by the general practitioner remains problematic and often gives significant results only in a late stage of heart valve disease. Valve stenoses and insufficiencies are nowadays diagnosed with accurate but expensive ultrasonic devices. This study aimed to develop a new heart sound analysis method for diagnosing aortic valve stenoses (AVS) based on a wavelet and correlation technique approach. Heart sounds recorded from 373 patients (107 AVS patients, 61 healthy controls (REF) and 205 patients with other valve diseases (OVD)) with an electronic stethoscope were wavelet filtered, and envelopes were calculated. Three correlations on the basis of these envelopes were performed: within the AVS group, between the groups AVS and REF and between the groups AVS and OVD, resulting in the mean correlation coefficients rAVS, rAVSv.REF and rAVSv.OVD. These results showed that rAVS (0.783 +/- 0.097) is significantly higher (p < 0.0001) than rAVSv.REF (0.590 +/- 0.056) and rAVSv.OVD (0.516 +/- 0.056), leading to a highly significant discrimination between the groups. The wavelet and correlation-based heart sound analysis system should be useful to general practitioners for low-cost, easy-to-use automatic diagnosis of aortic valve stenoses.

Adult↗