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S Aronson

Publications and source records attributed to S Aronson.

At least 55 records · Page 3Linked to original sources
PubMed1995

Retrograde-delivered cardioplegia is not distributed equally to the right ventricular free wall and septum.

Right ventricular myocardial protection during cardiac surgery continues to be a challenge. Retrograde delivery of cardioplegia has been shown to perfuse left ventricular regions subtended by critical coronary stenosis and not adequately protected by antegrade delivery. However, the distribution of cardioplegia from the coronary sinus to the right ventricle remains in question. A reliable means for assessing such flow distribution intraoperatively is provided by contrast echocardiography. It was hypothesized that conventional use of coronary sinus catheters for retrograde cardioplegia delivery does not reliably perfuse the myocardial region subtended by the right coronary artery. Six patients scheduled to undergo elective coronary artery bypass surgery were evaluated with contrast echocardiography to determine the distribution of retrograde-delivered cardioplegia into the right ventricle. Sonicated Renografin-76 (Squibb Diagnostics, Princeton, NJ) was injected during retrograde delivery of cold crystalloid cardioplegia solution and continuous two-dimensional ultrasound imaging of the heart. On-line videodensitometric analysis was performed with a digital ultrasound system. The area under the curve and peak pixel intensity were determined for the anterior septum, the posterior septum, and the right ventricular free wall for each contrast injection. Recorded VHS videotape images of contrast-enhanced perfusion patterns were also reviewed and scored. On-line acoustic-densitometric analysis showed that right ventricular posterior and anterior septal peak pixel intensities were 4.8 +/- 3.2 and 7.3 +/- 1.5, respectively, compared with only 1.6 +/- 1.2 (p < or = 0.05) in the right ventricular free wall.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1995

Five girls in search of a group: a group experience for adolescents of parents with AIDS.

This paper depicts a pilot school-based bereavement group initiated by four junior-high-school girls who experienced crying spells and suicidal ideation following a classroom discussion on AIDS. It emerged that each of these youths had recently lost (or was in the process of losing) a close family member to the disease. Several key concepts of grief work with children are briefly reviewed and the implementation of this group in a public junior high school in the Bronx is described. Examples of group process are provided highlighting phases of group development and themes of the group. Suggestions for future work in this area are provided.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Safety and feasibility of renal blood flow determination during kidney transplant surgery with perfusion ultrasonography.

Contrast-enhanced perfusion patterns of newly transplanted kidneys were determined in 10 patients. Albumin-stabilized sonicated microspheres were injected into the iliac-renal artery of the transplanted kidney while continuous two-dimensional ultrasound images were recorded. Doppler derived resistance index (RI) of the transplanted kidney's blood flow before injection of contrast (0.68 +/- 0.8) did not differ significantly from RI measured immediately after injection (0.72 +/- 0.13) or RI 24 h after surgery (0.69 +/- 0.11). Heart rate, mean arterial pressure, central venous pressure, and electrocardiogram (ECG) signs for ischemia did not change during contrast injections. Renal scintigraphy and renal biopsy revealed acute tubular necrosis and/or rejection in two patients at 24-48 h. Videodensitometry was used to assess the ratio of inner to outer peak pixel intensity from the recorded tomographic images in six patients. In both patients with acute rejection, the inner to outer cortex peak pixel intensity was greater than 1, whereas it was less than 1 in the remaining four patients with normal postoperative renal function. Visual scores (0-3) of contrast enhancement for three doses of Albunex were evaluated (0.5 mL, 1.0 mL, 2.0 mL). Two milliliters always enabled perfusion assessment. In seven patients the identical dose of Albunex was injected immediately before and 30 s after 2 mg of verapamil was injected directly into the renal artery at the time of surgery. The contrast enhancement score before verapamil (1.4 +/- 0.6) was significantly less than the enhancement score after (2.1 +/- 0.6), implying greater renal blood flow after verapamil.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Family history and the risk of prostatic carcinoma in a high risk group of urological patients.

PURPOSE: We examine the association of family history and prostatic carcinoma. MATERIALS AND METHODS: A total of 2,968 consecutive patients referred for prostate cancer detection responded to a questionnaire and underwent transrectal ultrasound examination with or without biopsy. RESULTS: Of the men 329 (11.1%) had a family history of prostate cancer. No differences were observed between groups with and without a family history with respect to mean patient age, serum prostate specific antigen level or biopsy rate. Prostate cancer was detected in 133 of 329 patients (40.4%) with a family history and 769 of 2,639 (29.1) with no family history (p < 0.001, odds ratio 1.7). No significant differences were observed between cancer patients with or without a family history with respect to mean Gleason score (6.0 versus 6.2), patient age at diagnosis (65.8 versus 66.7) and prostate specific antigen level (16.8 versus 17.1). CONCLUSIONS: Patients with a family history of prostate cancer have a greater risk of the disease. In this select group of patients a positive family history was not associated with an earlier age at cancer diagnosis or a different histological grade of tumor.

Aged↗
PubMed1995

Evaluation of changes in skeletal muscle blood flow in the dog with contrast ultrasonography.

Intraoperative methods to assess skeletal muscle blood flow or muscle-flap perfusion during vascular reconstructive surgery are limited. At present, techniques enable only anatomic identification of the degree of patency of large vessels. We report here the first use of ultrasonography to assess dynamic changes in skeletal muscle perfusion. Baseline blood flow in the adductor muscle group of the hindlimbs of seven dogs was measured with an electromagnetic flow probe and with contrast ultrasound using the contrast agent Albunex. Blood flow was manipulated in each dog pharmacologically with random administration of intraarterial injections of Neo-Synephrine and papaverine. After each change in blood flow detected by electromagnetic flow probe, flow also was assessed qualitatively by four independent observers who graded video-recorded contrast enhancement in the muscle group on a 0 to 4 scale. Videodensitometry also was used to generate time versus intensity curves in the adductor muscle region of interest. Peak pixel intensity was determined during each flow condition. A total of 21 flow measurements were made with each assessment scheme (electromagnetic flow probe, video enhancement, videodensitometry) for each condition (7 control, 7 papaverine, 7 Neo-Synephrine). Changes in blood flow assessed by video enhancement scores and changes in peak pixel intensity correlated with changes measured by electromagnetic flow probe (r = 0.84 and 0.66, respectively). We conclude that contrast ultrasound may be used to detect changes in skeletal muscle perfusion intraoperatively. Measures of muscle perfused by visual inspection of contrast enhancement and videodensitometric data were in agreement with direct measurements of changes in skeletal muscle blood flow.

Animals↗
PubMed1994

Intraoperative perfusion echocardiography.

The ability to assess perfusion intraoperatively should enable end-organ evaluation of the effects of therapeutic choices and provide a basis for understanding the mechanisms of disease. Several experimental techniques for assessment of tissue perfusion are being evaluated; contrast echocardiography appears to be adaptable to the perioperative setting because of its portability and relatively modest cost. With further improvements in commercial ultrasound imaging devices and ultrasonic contrast agents, intraoperative contrast echocardiography may prove to be a technique for quantitation of tissue perfusion. Contrast echocardiography is currently being used intraoperatively to assess cardioplegia distribution, coronary bypass graft patency, and coronary artery collateral vessel distribution. In addition, relative change in renal blood flow can be assessed during renal transplant surgery. With continued advancement of ultrasound technology providing linear (or known) acoustic signal response and wider dynamic range for detection of small and large concentrations of contrast agents, tissue blood flow may soon be evaluated with even greater precision.

Animals↗
PubMed1994

Prospective evaluation of prostate-specific antigen density and systematic biopsies for early detection of prostatic carcinoma.

Significant controversies persist in regard to the need for systematic biopsies in patients with serum prostate-specific antigen (PSA) levels above 4 ng/mL (Hybritech assay), especially if they show no signs of prostatic cancer on digital rectal examination (DRE) or transrectal ultrasonography (TRUS). We evaluated 565 consecutive patients referred to us for prostatism, suspicious lesions on DRE, or an elevated serum PSA level. These patients do not represent a purely screened population. A detection rate of 38.4 percent was achieved by performing directed biopsies of suspicious lesions on DRE and/or TRUS, and systematic biopsies of all patients with serum PSA levels above 4 ng/mL. Among 142 patients with serum PSA between 4.1 and 10 ng/mL, but without suspicion for cancer on DRE and TRUS (DRE- TRUS-), a large number of patients (6.2) were subjected to systematic biopsies to detect one cancer. A receiver-operating characteristics curve for PSA density (PSAD) applied to this population confirmed that the best cut-off point for biopsies was a PSAD of 0.15, below which only two of twenty-three cancers would have been missed, sparing biopsies in 77 of 142 patients. A similar approach was applied to DRE- TRUS- patients with serum PSA levels above 10 ng/mL. The number of cancers in those with serum PSA between 10.1 and 14 ng/mL was too low to establish a PSAD cut-off point. In patients with serum PSA above 14 ng/mL, the best PSAD cut-off point for biopsies was 0.3, below which two of thirteen cancers would have been missed, sparing biopsies in 19 of 39 patients. We conclude that PSAD can safely reduce the number of patients subjected to systematic biopsies without significantly compromising cancer detection.

Adult↗
PubMed1994

Growth as a parameter of inflammation in Crohn's disease, using roentgen stereophotogrammetric analysis.

Growth rate was measured in 12 children with Crohn's disease and growth retardation, using roentgen stereophotogrammetric analysis. The method was chosen as it provides an opportunity to record growth rate accurately during short periods of time. Growth was followed at variable intervals of 4-12 weeks depending on the clinical situation. Growth rate was shown to correlate with symptoms, laboratory tests and nitrogen balance. These findings indicate that growth, when it is affected, fluctuates in a similar way as albumin, acute phase proteins and symptoms, all assumed to reflect the disease activity. Short-term growth measurements appear to be helpful in monitoring the disease progress or response to therapy in children with Crohn's disease, particularly when growth retardation is the only manifestation of the disease.

Adolescent↗
PubMed1994

Predictive and diagnostic tests of renal failure: a review.

Postoperative acute renal insufficiency is a discouraging complication with a mortality rate that remains persistently high, despite improved techniques of dialysis and advances in the perioperative management of hemodynamic, metabolic, and infective complications. A complete understanding of the role of renal hemodynamics in the pathophysiology of acute renal failure still has not emerged. Serial determination of creatinine clearance is currently the most sensitive test for predicting the onset of perioperative renal dysfunction; however, the test is not practical for measuring renal function under operating room conditions. Furthermore, testing creatinine clearance is time-consuming, labor intensive, and may cause significant delay in identifying the onset of renal dysfunction. That early therapy modifies the prognosis of renal dysfunction remains an untested hypothesis until a measurement that predicts renal outcome is found that is sensitive, specific, and easily obtainable. The ability to measure intrarenal blood flow distribution may offer promise for improving our predictive and diagnostic abilities to assess perioperative acute renal failure. Methodologic constraints, however, limit the practicality of this measurement in the perioperative setting at this time. Instead, we rely on indirect variables that do not bear a reliable relationship to glomerular filtration rate and renal function.

Acute Kidney Injury↗
PubMed1994

Association of preoperative risk factors with postoperative acute renal failure.

We performed a systematic review of 28 studies that examined preoperative risk factors for postoperative renal failure. Included in the studies were 10,865 patients who underwent either vascular, cardiac, general, or biliary surgery. No two studies used the same criteria for acute renal failure. Variability in definitions of renal failure, lack of consistent criteria for establishing risk factors, and nonuniformity in the statistical methods employed result in a literature that is not adequate to support a comprehensive quantitative review. Of the 30 variables considered in the studies, preoperative renal risk factors, such as increased serum creatinine, increased blood urea nitrogen, and preoperative renal dysfunction were repeatedly found to predict postoperative renal dysfunction. The literature provides little quantitative information concerning the degree of risk associated with other factors. Cardiac risk factors, such as left ventricular dysfunction, were reported to be predictive of postoperative renal failure more consistently than was advanced age.

Acute Kidney Injury↗
PubMed1994

The relationship between immediate outcome after cardiac surgery, homogeneous cardioplegia delivery, and ejection fraction.

BACKGROUND: Optimal myocardial protection during cardiac surgery with ischemic arrest is predicated on among other variables, homogeneous cardioplegia distribution. Contrast echocardiography has been shown to provide information regarding the intramyocardial distribution of cardioplegia solution. To test the hypothesis that information regarding cardioplegia distribution derived from contrast echocardiography may be associated with immediate clinical outcome after cardiac surgery, data from 21 patients were examined retrospectively. METHODS: Contrast-enhanced cardioplegia distribution patterns of the left ventricle short axis view obtained with transesophageal echocardiography were examined off-line by four observers blinded to clinical outcome. Contrast effect was scored for eight equally divided myocardial segments (0 = no contrast, 1 = nonuniform contrast, 2 = uniform contrast, 3 = excessive contrast). The scores were then averaged between segments and between observers to generate an antegrade, a retrograde, and a combined global contrast score for each patient. RESULTS: Seventeen patients were separated from bypass without difficulty (group A) and 4 patients required sustained inotropic therapy or an intra-aortic balloon pump to facilitate separation from bypass (group B). As would be expected, group A patients had a higher average preoperative ejection fraction than did group B patients (60 percent +/- 14 vs 31 percent +/- 7, p < 0.01). In group A, however, for 4 of 17 patients (23 percent), low preoperative ejection fraction was not predictive of postoperative exogenous circulatory support requirements. Group A patients also had significantly higher antegrade (1.6 vs 1.2, p < 0.02), retrograde (1.7 vs 1.1, p < 0.02), and combined global contrast scores (1.7 vs 1.1, p < 0.01) than did group B patients. All patients with low preoperative ejection fraction and low intraoperative contrast scores required exogenous support to separate from cardiopulmonary bypass. CONCLUSION: Contrast echocardiography makes possible an evaluation of the intensity and distribution of contrast-enhanced cardioplegia delivery and we believe the efficacy of intraoperative myocardial protection. Although low preoperative ejection fraction is a known predictor of poor immediate postoperative outcome following cardiac surgery, not all patients with low preoperative ejection fractions require inotropic support postoperatively. Our results suggest that monitoring cardioplegia distribution with contrast echocardiography may offer insight for better patient stratification based on intraoperative myocardial protection in patients with low ejection fraction. We believe a more extensive evaluation of this relationship should be pursued in a prospective manner.

Aged↗
PubMed1994

Plasma and urinary levels of vasopressin in enuretic and non-enuretic children.

Plasma and urinary levels of vasopressin were measured by radioimmunoassay in 18 children with primary nocturnal enuresis and 20 age and sex matched controls. All subjects followed a protocol whereby all urine were collected and divided up into daytime (8 a.m.-8 pm) and night-time (8 p.m. - 8 a.m.) samples. Urine osmolality and urinary vasopressin levels were measured and, following an overnight observation period, the following morning (8 a.m.) plasma vasopressin was measured. Plasma vasopressin was significantly lower in the enuretic group (2.86 +/- 0.44 pg/ml) compared to the control group (3.64 +/- 1.35 pg/ml) (p = 0.011). Total urinary vasopressin excretion over 24 hours was lower in the enuretic group but the difference was not significant. These results support the hypothesis that one of the factors responsible for nocturnal enuresis in children may be due to a reduced nocturnal secretion of vasopressin. This may explain why the vasopressin substitution therapy is able to successfully abolish nocturnal enuresis symptoms.

Adolescent↗
PubMed1993

Identifying stunned myocardium during cardiac surgery: the role of myocardial contrast echocardiography.

Differentiation of reversibly stunned myocardium from irreversibly damaged (infarcted) myocardium is critically important in patient management. Current methods for monitoring myocardial function yield only nonspecific assessments of myocardial viability. On the other hand, myocardial contrast echocardiography (MCE) can be used to evaluate the extent of myocardial perfusion as well as the efficacy of myocardial protection in patients undergoing coronary artery bypass graft (CABG). This system includes an external ultrasound unit and an internal tracer, usually gaseous microbubbles, which reflect the ultrasonic beam. Previous studies have shown that myocardial risk areas identified with MCE correlate with areas defined by technetium autoradiography and infarction size. We have used MCE to evaluate coronary artery bypass patients (N = 21) with regard to myocardial function and cardioplegia perfusion patterns. A significant correlation (p < 0.01) was found between abnormal contrast enhanced cardioplegia patterns and depression of left ventricular function. Refinements to ultrasound technology and contrast agents will further enhance the diagnostic power of MCE for the quantification of myocardial blood flow.

Cardiac Surgical Procedures↗
PubMed1993

Assessment of renal blood flow with contrast ultrasonography.

Sonicated albumin microspheres, a digitalizing ultrasound system, and a mathematical model for flow were used to determine whether blood flow in the canine kidney could be assessed with contrast ultrasound. Albunex ultrasound contrast microspheres were injected into the aorta while ultrasound images of the kidney and aorta were recorded simultaneously. Ultrasound data were obtained during contrast injections at 93 different renal blood flow rates in nine dogs. Contrast dose was calibrated to ultrasound system response for both aortic and renal images. A linear relationship between microbubble concentration used and pixel intensity was established (r = 0.89 for aortic images and r = 0.91 for renal images). Renal blood flow was manipulated from baseline by means of a hydraulic renal artery occluder and by intravenous dopamine or fenoldopam infusion. Blood flow calculated with contrast ultrasonography was compared with direct measurement obtained with an electromagnetic flow probe at each flow rate. Direct measurement correlated with rates calculated with contrast ultrasonography (r = 0.84, 95% confidence limits from 0.75 to 0.90). Overall, calculations tended to overestimate absolute flow measurements, and overestimation of flow tended to be greater during pharmacologically manipulated flow rates. We conclude the changes and trends in renal blood flow can be serially assessed in vivo with contrast ultrasonography, but technical limitations of present commercial ultrasounds systems preclude absolute quantification at this time.

Albumins↗
PubMed1993

Myocardial distribution of cardioplegic solution after retrograde delivery in patients undergoing cardiac surgical procedures.

The myocardial distribution of both antegrade and retrograde cardioplegia for cardiac surgical intervention, after induction of cardioplegia via the aortic root, was directly assessed and compared in 19 patients by means of contrast echocardiography. Two-dimensional transesophageal echocardiographic images of the short axis of the left ventricle at the level of the papillary muscles were obtained after sonicated Renografin-76 microbubbles were injected into an aortic root and/or transatrial coronary sinus catheter during delivery of cardioplegic solution. Segmental distribution of cardioplegic solution was immediately noted in the myocardium at the time of contrast injections. In 11 of 18 patients (61%) cardioplegic solution was dispersed to all left ventricular myocardial segments after antegrade delivery. In 17 of 19 patients (90%) retrogradely delivered cardioplegic solution (after antegrade induction of cardioplegia in 18 of the 19 patients) was dispersed to all the left ventricular myocardial segments, including the septum. In 2 of the patients, initial lack of retrograde distribution of cardioplegic solution was remedied when the coronary sinus catheter was repositioned and contrast cardioplegic solution was reinjected. Imaging of the right ventricle was possible in only 4 of the 19 patients and revealed that after retrograde delivery, cardioplegic solution had been at least partially distributed to the right ventricle as well. We performed off-line videodensitometric analysis in 9 patients after retrograde delivery of cardioplegic solution. Mean peak pixel-intensity ratio of flow from the endocardium to the epicardium in the left ventricular free wall was 1.46 +/- 0.27, and mean peak pixel-intensity ratio of flow from the left to the right intraventricular septal endocardium was 1.39 +/- 0.33 (p < or = 0.05).

Aged↗