Does Doppler myocardial imaging give new insights or simply old information revisited?
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Arrhythmias, Cardiac↗
Biomedical subjects
A Fleming
Publications and source records attributed to A Fleming.
Latissimus dorsi muscle: assessment of stimulation after cardiomyoplasty with Doppler US tissue imaging.
PURPOSE: To evaluate Doppler ultrasound (US) tissue imaging for assessment of stimulated skeletal muscle contraction. MATERIALS AND METHODS: Seven patients were studied after left latissimus dorsi cardiomyoplasty. Myograft contraction programmed on alternate cardiac cycles was assessed with Doppler US tissue imaging. Beat-to-beat variation in inferior wall motion was assessed by examining peak myograft velocities during 10 muscle-assisted and 10 nonassisted cardiac cycles. The temporal relationship between electrostimulation and myograft contraction, changes in cardiac geometry, and the effect of alterations in stimulation voltage and muscle synchronization were assessed. RESULTS: Significant beat-to-beat variation in velocity profile could be detected in the proximal myograft in six patients (P < .05). Potentiation of infero-posterior wall motion was measurable in five patients (mean peak systolic wall velocity: nonassisted, 2.5 cm.sec-1 +/- 0.5 [standard deviation]; assisted, 7.8 cm.sec-1 +/- 6.3). The response between stimulation voltage and inferoposterior wall velocity was sigmoid. CONCLUSION: Doppler US tissue imaging depicted the effects of myostimulator programming on muscle contraction and ventricular wall motion.
Cardiomyoplasty↗
Beyond drug regulation: the science of drug evaluation.
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Drug Approval↗
National Medical Association Surgical Section position paper on violence prevention. A resolution of trauma surgeons caring for victims of violence.
The epidemic of intentional injury continues to be a leading cause of premature death in America. The ravages of violence are particularly devastating within the minority community. With this position paper from the Surgical Section of the National Medical Association (the country's oldest and largest organization of minority physicians), a group of trauma surgeons and surgical intensivists resolve to focus on underused violence prevention opportunities and to extend their spheres of influence beyond the walls of their institutions and emphasize violence prevention activities.
Humans↗
Clinical evaluation of continuous noninvasive blood pressure monitoring: accuracy and tracking capabilities.
A continuous, noninvasive device for blood pressure measurement using pulse transit time has been recently introduced. We compared blood pressure measurement determined using this device with simultaneous invasive blood pressure measurements in 35 patients undergoing general endotracheal anesthesia. Data were analyzed for accuracy and tracking ability of the noninvasive technique, and for frequency of unavailable pressure measurements by each method. A total of 25,133 measurements of systolic pressure, diastolic pressure, and mean arterial pressure (MAP) by each method were collected for comparison from 35 patients. Accuracy was expressed by reporting mean bias (invasive pressure minus noninvasive pressure) and limits of agreement between the two measurements. After correction for the offset found when measuring invasive and oscillometric methods of arterial pressure measurement, the mean biases for systolic, diastolic, and mean pressures by the pulse wave method were -0.37 mm Hg, -0.01 mm Hg, and -0.05 mm Hg, respectively (p < 0.001). The limits of agreement were: -29.0 to 28.2 mm Hg, -14.9 to 14.8 mm Hg, and -19.1 to 19.0 mm Hg, respectively (95% confidence intervals). When blood pressure measured invasively changed over time by more than 10 mm Hg, the noninvasive technique accurately tracked the direction of change 67% of the time. During the entire study, 3.2% of the invasive measurements were unavailable and 12.9% of the noninvasive measurements were unavailable. The continuous noninvasive monitoring technique is not of sufficient accuracy to replace direct invasive measurement of arterial blood pressure, owing to relatively wide limits of agreement between the two methods.(ABSTRACT TRUNCATED AT 250 WORDS)
Blood Pressure Determination↗
Skeletal muscle contraction in healthy volunteers: assessment with Doppler tissue imaging.
PURPOSE: To evaluate Doppler tissue imaging (DTI) in the measurement and characterization of skeletal muscle movement and contraction. MATERIALS AND METHODS: Five healthy male subjects were examined with a commercially available ultrasound imaging unit modified for DTI. Velocities of the rectus femoris and gastrocnemius-soleus muscle motion were measured during the patellar and ankle reflexes, respectively. Velocity profiles were analyzed after digitization of the DTI images. Time to peak velocity, velocity range, and relaxation time were examined in each case over three contractions. For reflex contractions, reproducibility was examined by determining the latency period, area under the velocity curve, and duration of contraction for each of five consecutive reflexes. RESULTS: Isotonic muscle contraction could be distinguished from passive movement by a higher tissue velocity range, by a more rapid initial acceleration slope, and by the velocity differential across the muscle. The intensity and duration of the contraction and plateau and relaxation phases of isotonic contraction could be measured in all muscle groups. CONCLUSION: DTI provides detailed information about the dynamics of skeletal muscle contraction.
Adult↗
[Doppler tissue imaging: current status and future prospects].
Colour Doppler myocardial imaging is a new technique which allows the visualization in the colour Doppler of myocardial tissues, instead of blood pool imaging. To permit the acquisition of this information some modifications are essential in the machine. The gain has to be reduced so that, firstly, the echoes from ventricular walls were similar to those from the blood pool. Secondly the Doppler velocity range has to be reduced to correspond to the normal velocity of the ventricular wall. These modifications allow the tissue echoes to pass the clutter filter and to be displayed in colour on the video screen. This technique may be able to evaluate the velocity of myocardial tissue, the acceleration and the strength within the myocardial wall with these maps, obtained by modifications in the software, called Velocity Map, Acceleration Map, Energy Map. The clinical applications of this technique are: 1) in the area of myocardial functions e.g.: measurements, volumes, diastolic functions; 2) in the area of myocardial ischemia e.g.: wall motion abnormalities, viability studies, perfusion with contrast agents, stress echo, infarct identification; 3) in the area of myocardial depolarisation e.g.: arrhythmias evaluation, ablation monitoring. Doppler tissue imaging in spite of good results obtained, needs a large clinical studies.
Coronary Disease↗
Isolation of suppressors of temperature-sensitive folding mutations.
Mutations in the tailspike gene (gene 9) of Salmonella typhimurium phage P22 have been used to identify amino acid interactions during the folding of a polypeptide chain. Since temperature-sensitive folding (tsf) mutations cause folding defects in the P22 tailspike polypeptide chain, it is likely that mutants derived from these and correcting the original tsf defects (second-site intragenic suppressors) identify interactions during the folding pathway. We report the isolation and identification of second-site revertants to tsf mutants.
Bacteriophage P22↗
Drug management of arthritis in the elderly.
Rheumatic disorders are common in the ageing population requiring the use of DMARDs and immunosuppressive therapy as with younger patients. Indications for therapy are approximately the same in both groups, but toxic side-effects are probably more common in the elderly necessitating close supervision of indications and drug requirements. Local injection techniques The practice of local injection of corticosteroid in musculo-skeletal disorders is widespread. The literature on comparative efficacy between different preparations is scanty. These techniques can give significant relief in rheumatoid arthritis, osteoarthritis, sero negative arthropathies, crystal induced arthritis and many soft tissue lesions. Severe joint and soft tissue lesions are common in the elderly. In these patients even a small loss of physical function may have a markedly detrimental effect on independence. Such lesions should therefore be actively sought and vigorously treated. Often a simple, rapidly acting, local corticosteroid injection is preferable to a prolonged course of either NSAIDs or physiotherapy. In general, such injections should not be used if the diagnosis is uncertain, or there is any suspicion of infection, or if there has been a previous severe local reaction. Injections that are becoming too regular mean that the technique has not proved successful and other therapies should be sought. In performing the injections, antisepsis should be scrupulous and a 'no-touch' technique used. Accuracy of needle placement is necessary for good results. Injections should not be given against pressure as this generally means incorrect sitting. Some systemic absorption does occur.(ABSTRACT TRUNCATED AT 250 WORDS)
Aged↗
The Glasgow Coma Scale and prognosis in gunshot wounds to the brain.
To determine which factors predict survival in patients with gunshot wounds to the brain, 192 patients who had intracranial injury demonstrated on computed tomographic (CT) scanning were retrospectively reviewed. Glasgow Coma Scale (GCS) scores on admission seemed to be the most important factor in predicting survival. Age, the presence of extruded brain, and use of a shotgun could not be shown to be factors independent of admission GCS score. Findings on CT scans (single lobe vs. multilobe involvement) helped to predict survival only in patients with GCS scores 5-13. The mortality rate was 35%. Among survivors 18% had brain-related long-term disability, and an additional 27% had long-term disability related to associated eye injury.
Adolescent↗
Report on the NACOSA conference (National AIDS Convention of South Africa).
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Acquired Immunodeficiency Syndrome↗
Open laparoscopic cholecystectomy in pregnancy.
Since the introduction of laparoscopic cholecystectomy in 1989, surgeons worldwide have become familiar with the basic techniques involved. Pregnancy has previously been considered an absolute contraindication to laparoscopic cholecystectomy; however, we present three cases of laparoscopic cholecystectomy in pregnancy. If conservative management fails, this method, far from being absolutely contraindicated, should be the procedure of choice in pregnancy, as it has already become in nonpregnant patients. Transvaginal ultrasound allows continuous monitoring of fetal heart rate in all stages of pregnancy after the 7th week. The open (Hasson) technique should be strongly considered if accidental uterine puncture and potential fetal damage are to be avoided.
Adolescent↗
South Africa and AIDS: seven years wasted.
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Acquired Immunodeficiency Syndrome↗
Kinetics of anti-CD4-induced T helper cell depletion and inhibition of function. Activation of T cells by the CD3 pathway inhibits anti-CD4-mediated T cell elimination and down-regulation of cell surface CD4.
In vivo treatment with anti-CD4 antibody profoundly suppresses a number of T cell-dependent responses and is clinically useful in the treatment of certain mouse models of autoimmune disease. Treatment with anti-CD4 antibody will inactivate and can deplete CD4 T cells, but the mechanisms responsible for these effects are incompletely understood. When mouse spleen cells were exposed in vitro to both SRBC and monoclonal anti-CD4, there was 55% reduction of the anti-SRBC response. If cultures were preincubated with anti-CD4 for 48 h before in vitro challenge, the reduction was greater than 80%. When unfractionated spleen cells were cultured with anti-CD4 for 96 h, there was actual elimination of CD4 cells in these cultures since virtually all CD3+ cells were CD8+. Activation of T cells by exposure to anti-CD3 rendered them resistant to antibody-mediated CD4 depletion. This resistance to CD4 depletion was seen even in cultures that were pretreated with anti-CD4 for as long as 24 h before anti-CD3 exposure. In cultures of purified T cells, anti-CD4 did not eliminate CD4 T cells. However, culture of T cells with macrophage-rich adherent cells and anti-CD4 resulted in elimination of CD4 T cells. Thus, it appears that macrophages play a role in anti-CD4-induced T cell elimination. While anti-CD4 did not eliminate CD4 cells from a population of purified T cells, there was profound down-regulation of cell surface CD4. Activating T cells with immobilized anti-CD3 before addition of anti-CD4 prevented down-regulation of CD4. These experiments demonstrate that T cell activation by anti-CD3 renders the activated cells resistant to antibody-induced CD4 down-regulation and to antibody-induced CD4 T cell depletion. These findings may have relevance to the application of anti-CD4 therapy in human diseases that are mediated by activated Th cells.
Antigen-Antibody Reactions↗
Prospective trial of supranormal values as goals of resuscitation in severe trauma.
We prospectively tested the effect of the early postinjury attainment of supranormal values of cardiac index (> or = 4.52 L/min per square meter), oxygen delivery (> or = 670 mL/min per square meter), and oxygen consumption (> or = 166 mL/min per square meter) on outcome in traumatized patients with an estimated blood loss of 2000 mL or more. The goals in control patients were to attain normal values for all hemodynamic measurements. During the 6-month period, 33 protocol patients and 34 control patients with similar vital signs, estimated blood losses, and severity of injuries were enrolled in the study. Eight (24%) protocol patients died, while 15 (44%) control patients died. The protocol patients had fewer mean (+/- SEM) organ failures per patient (0.76 +/- 1.21 vs 1.59 +/- 1.60), shorter stays in the intensive care unit (5 +/- 3 vs 12 +/- 12), and fewer mean days requiring ventilation (4 +/- 3 vs 11 +/- 10) than did the control patients (P < .05 for each). We conclude that attaining supranormal circulatory values improves survival and decreases morbidity in the severely traumatized patient.
Adolescent↗
Evaluation of a comprehensive algorithm for blunt and penetrating thoracic and abdominal trauma.
The objective was to develop a single branched-chain decision tree for both blunt and penetrating thoracic and abdominal trauma and to test its feasibility to track clinical decisions. The algorithm consisted of 14 specific patient management loops and 31 decision nodes. During a 4-month period, the management decisions and clinical course of 434 trauma patients were prospectively observed. Thirty-four patients had no signs of life on arrival to the emergency department (ED) and were excluded from the statistical evaluation; the remaining 400 patients constituted the study group. The mean Injury Severity Score (ISS), Penetrating Abdominal Trauma Index (PATI), and Trauma Score (TS) scores in the series were 21 +/- 10, 34 +/- 12, and 13 +/- 3. The overall patient mortality of the study group was 17 per cent; it was 61 per cent in those patients with major deviations from the algorithm and 6 per cent in patients who complied with the algorithm. The ISS, PATI, and TS scores were 29 +/- 9, 32 +/- 12, and 13 +/- 2 in patients with deviations and 20 +/- 10, 37 +/- 12, and 14 +/- 2 in patients who complied with the algorithm. Of the 37 patients who died with major deviations from the algorithm, the deviation was directly contributory to death in 21 cases (57%) and probably contributory in another 14 cases (38%). There were 108 patients with ISS scores between 20 and 50. In this group, mortality was 55 per cent when a major deviation occurred and 5 per cent without major deviations from the algorithm. The authors conclude that the survival of trauma patients may be improved by following the specific management criteria outlined by the algorithm.
Abdominal Injuries↗
The relationship between ARDS, pulmonary infiltration, fluid balance, and hemodynamics in critically ill surgical patients.
Hypervolemia from fluid overload with resultant pulmonary edema is thought to be a frequent cause of Adult Respiratory Distress Syndrome (ARDS). However, ARDS may also occur as a result of the hypovolemic shock of surgery or trauma. To develop an appropriate rationale for fluid therapy in high-risk surgical patients, the relationship between fluid balance, hemodynamics, the onset of ARDS by physiologic criteria (shunt greater than or equal to 20%, and/or PaO2/FiO2 ratio less than 250) and the onset of pulmonary infiltration (PI) associated with ARDS were examined. Fifty patients were prospectively followed from admission throughout their hospitalizations; 38 (76%) had trauma and 12 (24%) were postoperative. Cardiac index, central venous pressure (CVP), wedge pressure (WP), and shunt (Qsp) were measured. All chest x rays were read by one staff radiologist who was blinded to the patients' identities. PI was graded from "0" to "4" (0 = no PI, 4 = maximum PI). The first x ray reading of "2" or greater was used as the time of onset of PI. ARDS by physiologic criteria occurred in 29 of 50 (58%) patients; 27 of these 29 (94%) also developed +2 or greater PI. The mean onset times of ARDS and of +2 PI were 40 +/- 41 hours and 40 +/- 38 hours, respectively. The ARDS patients had a significantly smaller net positive fluid balance than the non-ARDS patients over the first 40 hours after admission (+6,831 ml +/- 4,909 ml vs 12,440 ml +/- 7,817 ml, (P less than 0.01)).(ABSTRACT TRUNCATED AT 250 WORDS)
Adolescent↗
Information-seeking and maternal self-definition during the transition to motherhood.
The self-definitional processes accompanying the transition to motherhood were examined in this study. A cross-sectional sample of more than 600 women who were planning to get pregnant within 2 years, pregnant, or in the postpartum stage completed extensive questionnaires pertaining to their experiences of pregnancy and motherhood. On the basis of the assumption of the "self-socialization" perspective that individuals actively construct their identities in response to life transitions, our analyses focused on the role of information-seeking in the developing self-definitions of women becoming mothers. As predicted, (a) women actively sought information in anticipation of a first birth, (b) they used this information to construct identities incorporating motherhood, and (c) after the birth the determinants of their self-definitions shifted from indirect sources of information to direct experiences with child care. Hence, consistent with the self-socialization perspective, information-seeking did play an important role in the women's developing self-conceptions during this life transition. Mechanisms by which information gathered may alter self-conception are discussed.
Adolescent↗