PubMed HealthSearch

Biomedical subjects

D M Howard

Publications and source records attributed to D M Howard.

17 recordsLinked to original sources

Attributes of excellent attending-physician role models.

BACKGROUND: Although effective role models are important in medical education, little is known about the characteristics of physicians who serve as excellent clinical role models. We therefore conducted a case-control study to identify attributes that distinguish such physicians from their colleagues. METHODS: We asked members of the internal-medicine house staff at four teaching hospitals to name physicians whom they considered to be excellent role models. A total of 165 physicians named by one or more house-staff members were classified as excellent role models (these served as the case physicians in our study). A questionnaire was sent to them as well as to 246 physicians who had residency-level teaching responsibilities but who were not named (controls). Of these 411 physicians, 341 (83 percent) completed questionnaires while unaware of their case-control status. RESULTS: Of the 341 attending physicians who responded, 144 (42 percent) had been identified as excellent role models. Having greater assigned teaching responsibilities was strongly associated with being identified as an excellent role model. In the multivariate analysis, five attributes were independently associated with being named as an excellent role model: spending more than 25 percent of one's time teaching (odds ratio, 5.12; 95 percent confidence interval, 1.81 to 14.47), spending 25 or more hours per week teaching and conducting rounds when serving as an attending physician (odds ratio, 2.48; 95 percent confidence interval, 1.15 to 5.37), stressing the importance of the doctor-patient relationship in one's teaching (odds ratio, 2.58; 95 percent confidence interval, 1.03 to 6.43), teaching the psychosocial aspects of medicine (odds ratio, 2.31; 95 percent confidence interval, 1.23 to 4.35), and having served as a chief resident (odds ratio, 2.07; 95 percent confidence interval, 1.07 to 3.98). CONCLUSIONS: These data suggest that many of the attributes associated with being an excellent role model are related to skills that can be acquired and to modifiable behavior.

Baltimore

Voice development under training with and without the influence of real-time visually presented biofeedback.

This paper describes an investigation into the developmental nature of the voice under training with and without the influence of real-time visually presented biofeedback. Two subjects who had not previously experienced any form of vocal training took six singing lessons. One was taught conventionally, while the other was taught with the aid of a system known as Acoustic and Laryngeal Biofeedback Enhancement Real Time (ALBERT). Real-time biofeedback was presented based upon measures of (i) larynx closed quotient (CQ), (ii) spectral amplitude in the singer's formant frequency band relative to the spectral amplitude of the full band (ratio), and (iii) both parameters combined in a manner based on previously observed correlations between them. Results indicate generally increased sound pressure levels (SPL) of acoustic output and generally consistent increases in the level of CQ and ratio across consecutive lessons for both subjects.

Biofeedback, Psychology

ALBERT: a real-time visual feedback computer tool for professional vocal development.

This paper considers the nature of real-time visual feedback for vocal analysis and development and presents a new software tool, called ALBERT (acoustic and laryngeal biofeedback enhancement in real time), designed for use with those developing their voices professionally. This tool embodies several important issues in the provision of real-time visual feedback, including: (a) support for user-configurable visual displays, (b) the ability to use colour as a complementary or sole medium for the presentation of information, (c) the ability to combine algorithmically any number of vocal parameters to create a new single parameter representative of some aspect of vocal measurement which may be displayed and updated in real time, and (d) a rate of information update which may be altered by the user at any point for the most appropriate use according to the context of the feedback task. Several examples of system use are given, including the real-time display of fundamental frequency, jitter, and larynx closed quotient (CQ) parameters in a variety of visual configurations. Several examples are given relating to developing professional voice users, including the derivation of a new parameter which reflects the measure of progress of subjects along a linear correlation line between CQ and the level of energy in the singer's formant region.

Computers

Variation of electrolaryngographically derived closed quotient for trained and untrained adult female singers.

The derivation of larynx closed quotient (CQ) measures from the electrolarynogograph output is discussed and data are presented for a group of trained and untrained adult female singers (N = 26) for a sung two-octave G major scale. Statistically significant trends are observed between the trained and untrained groups that suggest for the trained group: (a) CQ tends to be lower for pitches below D4 and higher for pitches above B4, and (b) the gradient [CQ/log(F0)] tends to correlate positively with the number of years singing training/experience. These data are compared with those reported previously for an adult male group, and it is suggested that CQ could be a useful parameter to include in a real-time visual display for singing training.

Electric Stimulation

Double-blind, randomized, multicenter study of doxacurium vs. pancuronium in intensive care unit patients who require neuromuscular-blocking agents.

OBJECTIVE: To compare the neuromuscular-blocking and hemodynamic effects of doxacurium vs. pancuronium administered by intermittent bolus to intensive care unit (ICU) patients who required neuromuscular block to facilitate mechanical ventilation for > or = 24 hrs. DESIGN: A multicenter, prospective, double-blind, randomized study comparing doxacurium, a new benzylisoquinolone neuromuscular-blocking agent, with pancuronium. SETTING: ICUs of three tertiary care hospitals. PATIENTS: Forty critically ill patients (29 male, 11 female) with an average age of 52.5 yrs (range 19 to 80). INTERVENTIONS: With approval of our Institutional Review Boards and after obtaining informed consent, 40 critically ill patients were entered into the study. Histories and the results of physical examinations were recorded, laboratory data were collected, and Acute Physiology and Chronic Health Evaluation (APACHE) II scores were calculated during the 8 hrs before the start of the study medication. Patients received either doxacurium (initial dose of 0.04 mg/kg) or pancuronium (initial dose of 0.07 mg/kg) by bolus injection with continuous measurement of vital signs every minute for 15 mins. We measured the degree of neuromuscular blockade using a peripheral-nerve stimulator to measure the Train-of-Four count. Patients were rebolused (doxacurium dose of 0.025 mg/kg, pancuronium dose of 0.05 mg/kg) based on clinical criteria, which were substantiated by measurement of the Train-of-Four count. The neuromuscular-blocking drugs were stopped when the patient no longer required paralysis or after 5 days of therapy, whichever came first. Group comparisons were made using repeated measures analysis of variance, Fisher's exact test, and two sample t-tests, when appropriate. Spearman's rank-correction coefficients were calculated to assess the relationship of onset time and recovery time with all baseline laboratory values and the APACHE II scores. A p < .05 was used to establish statistical significance. MEASUREMENTS AND MAIN RESULTS: There were no differences between the two groups with respect to age, gender, or APACHE II scores. There were no differences between groups in terms of adverse experiences, nor with respect to time of onset of block, number of doses, or the duration of neuromuscular blockade (2.6 vs. 2.2 days for doxacurium vs. pancuronium, respectively). There was a statistically significant increase in heart rate after the initial dose of pancuronium (120 +/- 23 vs. 109 +/- 22 beats/min postinjection vs. preinjection, respectively; p < .05) without any differences noted after doxacurium (107 +/- 21 vs. 109 +/- 21 beats/min, respectively). Furthermore, once neuromuscular block was discontinued, the pancuronium group had a more prolonged and variable recovery time (279 +/- 229 mins) compared with the doxacurium group (138 +/- 46 mins, p < .05). CONCLUSIONS: In critically ill patients requiring neuromuscular block for > 24 hrs, doxacurium was well tolerated without evidence of tachycardia and with a relatively prompt recovery profile.

APACHE

A real-time LPC-based vocal tract area display for voice development.

This article reports the design and implementation of a graphical display that presents an approximation to vocal tract area in real time for voiced vowel articulation. The acoustic signal is digitally sampled by the system. From these data a set of reflection coefficients is derived using linear predictive coding. A matrix of area coefficients is then determined that approximates the vocal tract area of the user. From this information a graphical display is then generated. The complete cycle of analysis and display is repeated at approximately 20 times/s. Synchronised audio and visual sequences can be recorded and used as dynamic targets for articulatory development. Use of the system is illustrated by diagrams of system output for spoken cardinal vowels and for vowels sung in a trained and untrained style.

Equipment Design

Neurological melioidosis: seven cases from the Northern Territory of Australia.

Pseudomonas pseudomallei, which causes melioidosis, is most commonly associated with pulmonary infection. We describe seven patients who developed a neurological syndrome as the predominant manifestation of melioidosis: this syndrome was characterized by peripheral motor weakness (mimicking Guillain-Barré syndrome), brain-stem encephalitis, aseptic meningitis, and respiratory failure. Neurological melioidosis occurred in the absence of demonstrable foci of infection in the central nervous system (CNS) in five of six patients whose cerebrospinal fluid was available for culture. Computed tomography and magnetic resonance imaging of the brain and spinal cord of these patients were not suggestive of pyogenic infection, although the latter procedure detected brain-stem encephalitis. Autopsy findings in one case confirmed brain-stem encephalitis without evidence of direct bacterial infection. The clinical presentation of neurological melioidosis includes features of an exotoxin-induced neurological syndrome, with profound neurological disease occurring in the absence of apparent direct infection of the CNS. This syndrome appears to be a newly recognized clinical presentation of melioidosis.

Adult

Peak-picking fundamental period estimation for hearing prostheses.

A real-time peak-picking fundamental period estimation device is described which is used in advanced hearing prostheses for the totally and profoundly deafened. The operation of the peak picker is compared with three well-established fundamental frequency estimation techniques: the electrolaryngograph, which is used as a "standard" hardware implementations of the cepstral technique, and the Gold/Rabiner parallel processing algorithm. These comparisons illustrate and highlight some of the important advantages and disadvantages that characterize the operation of these techniques. The special requirements of the hearing prostheses are discussed with respect to the operation of each device, and the choice of the peak picker is found to be felicitous in this application.

Cochlear Implants

Amiodarone-induced lung toxicity. In vitro evidence for the direct toxicity of the drug.

Amiodarone, a new antiarrhythmic agent, is associated with serious lung toxicity. This study indicates that in vitro amiodarone can directly induce bovine pulmonary artery endothelial cells to form cytoplasmic lamellar inclusions characteristic of the lung biopsy findings described in vivo. These morphologic changes occur as soon as 4 hours after incubation with the drug and with as little as 1 microgram/ml (within the therapeutic range). Amiodarone-induced endothelial cell injury, monitored by 51Cr release, occurs with as little as 10-20 micrograms/ml. The data suggest that amiodarone toxicity to the lung may be primarily related to its direct toxic effect on lung cells, and that the characteristic morphologic changes of cytoplasmic inclusions may represent an early sign of the drug's effect.

Amiodarone

Health education needs assessment in an HMO: a case study.

Potential health education services for HMO subscribers are numerous and varied, ranging across the entire wellness to sickness spectrum. Because of cost consciousness and limited educational resources, careful needs assessment and selection of priorities are vital to the success of HMO health education efforts. The results of utilizing six needs assessment methodologies are presented in this case study. Consumer and provider involvement in the needs assessment process revealed five top priority health problems or opportunities for health education: membership education needs; overweight/obesity; self-care needs; hypertension; and smoking. These recommendations did not include perinatal and pediatric health education services as top priority needs, an outcome at variance with the results of the other needs assessment methodologies. This variance emphasizes the importance of employing multiple techniques in the needs assessment process. Problems in implementing various needs assessment methodologies are discussed as well as implications for health education practice.

Health Education