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E Spitznagel

Publications and source records attributed to E Spitznagel.

34 records · Page 2Linked to original sources

Exclusion of chromosomal mosaicism in amniotic fluid cultures: determination of number of colonies needed for accurate analysis.

Most laboratories use the in situ or flask culture method and a two-stage approach to mosaicism detection. Determination of the optimum number of metaphases to be counted depends largely on whether or not the colonies that grow from the cells in the amniotic fluid can be considered independent. Previous statistical analysis of data from mixed male and female amniocyte cultures indicated that for mosaicism detection these colonies can be considered independent (Cheung et al., 1990). This analysis was repeated with a set of mosaic cases from two independent prenatal diagnosis programmes. The same degree of colony independence was found with this set of data. This result was used to calculate the level of mosaicism that is excluded at a particular confidence level when set numbers of colonies are analysed at each stage. The tables generated apply directly to the in situ method and with modification they can be used with the flask method. The conclusions are (1) analysis of cells from multiple colonies enhances the likelihood of excluding true mosaicism; (2) analysis of more than one metaphase per colony offers little advantage in excluding mosaicism; and (3) the two-stage approach is the most efficient. These conclusions should be used together with the expected clinical outcome of the actual cytogenetic abnormality, as discussed by Hsu et al. (1992).

Amniotic Fluid↗

On-site prothrombin time, activated partial thromboplastin time, and platelet count. A comparison between whole blood and laboratory assays with coagulation factor analysis in patients presenting for cardiac surgery.

BACKGROUND: Although available hemostasis assays from institutional laboratories permit an analytical approach to diagnosis and treatment of coagulation disorders following cardiopulmonary bypass, their clinical utility has been limited by delays in obtaining results. The development of instrumentation for on-site testing allows rapid return of results. This study was designed to compare whole blood (WB) results obtained from on-site coagulation assays with values provided by our institutional laboratory (LAB). METHODS: After Institutional Human Studies Committee approval, 362 patients presenting for cardiac surgery requiring cardiopulmonary bypass were enrolled in this study. Prothrombin time (PT), activated partial thromboplastin time (aPTT), and platelet count (PLT) assays were performed in both WB and LAB systems. PT, aPTT, and PLT measurements were compared between WB and LAB assays using blood specimens obtained from at least two time points for each patient. Normal range values for both PT and aPTT methods were determined by using measurements from a normal reference population. Coagulation factor levels were measured in a subset of patients to characterize the response of PT and aPTT assays to individual and multiple factor levels. To employ Bayes' theorem and calculate predictive indexes (e.g., sensitivity, specificity), the disease or factor deficiency was determined using factor levels. Predictive indexes were used to evaluate the ability of PT and aPTT assays to identify factor deficiency. RESULTS: PLT counts were similar between systems. Linear regression and bias analysis demonstrated similar results for WB and LAB PT and discordant results for aPTT measurements. Both PT assays had a similar normal range, whereas a wider distribution of results was evident for the WB aPTT normal range. Although statistically greater slopes for factor:aPTT regressions were observed for the WB system, WB aPTT correlated better with factor V and with factor V, VIII, and XII levels (multivariate linear regression). Diagnostic performance for factor levels less than 0.3 and 0.4 U/ml was similar for both WB and laboratory PT and aPTT assays. WB and LAB PT and aPTT assays performed similarly in detecting factor deficiency in the period after cardiopulmonary bypass. CONCLUSIONS: WB PT and PLT values correlate well with those obtained from the LAB. The discrepancy between measurement systems in aPTT values is probably a reflection of both different normal ranges and responsiveness to factor deficiency. These WB assays provide coagulation results that can accurately identify patients with quantitative deficiencies in platelets and coagulation factors.

Adult↗

Predictors of mortality in alcoholic women: a 20-year follow-up study.

Very little is known about the factors that predict mortality in female alcoholics. This study investigates these predictors in 103 female alcoholics who were psychiatrically hospitalized between 1967 and 1968 and followed for over 20 years. The findings showed that age, benders, and/or delirium tremens, comorbidity, and 3-year posttreatment drinking status were associated with time to death. That older alcoholics and those with pathological drinking within 3 years after treatment had a significantly shorter time to death was not surprising. However, the association of benders with mortality indicated that women may be very sensitive to short periods of high concentrations of alcohol. Comorbidity also had an intriguing effect in that women with a history of depression were more likely to survive. The predictors of mortality in these female alcoholics differed from those of the male alcoholics in this sample. These differences will be discussed in future publications.

Adult↗

Comparison of activated coagulation time and whole blood heparin measurements with laboratory plasma anti-Xa heparin concentration in patients having cardiac operations.

Previous reports suggest that activated clotting times do not correlate with heparin concentration during cardiopulmonary bypass. This study was designed to compare whole blood heparin concentration and activated clotting time measurements with laboratory-based plasma heparin concentration. Sixty-two patients having cardiac operations requiring cardiopulmonary bypass were enrolled in this study. The study was conducted in two phases. In phase I of this trial, blood specimens were obtained from 30 patients before heparin administration and after each of three heparin doses (20, 80, and 150 U/kg). In phase II, blood specimens were obtained from 32 patients before heparin administration and 10 minutes after each of the following: heparin administration (250 or 300 U/kg), initiation of cardiopulmonary bypass, achievement of hypothermia, initiation of rewarming, and immediately before discontinuation of bypass. Blood specimens were used to measure activated clotting time (kaolin and celite), whole blood heparin concentration, and anti-factor Xa plasma heparin concentration. In phase I, activated clotting time (celite: r = 0.91; kaolin: r = 0.93) and whole blood heparin concentration (r = 0.98) measurements correlated well with plasma heparin concentration. After initiation of cardiopulmonary bypass (phase II), weak correlations for activated clotting time measurements (celite: r = 0.34; kaolin: r = 0.59) and a strong correlation for whole blood heparin concentration (r = 0.95) were evident when compared with plasma heparin concentration. During bypass, activated clotting time measurements also inversely correlated with temperature (celite: r = -0.21; kaolin: r = -0.19) and hematocrit (celite: r = -0.26; kaolin: r = -0.21). A weak correlation between activated clotting time measurements and plasma heparin concentration is evident during the cardiopulmonary bypass period, probably because of the influence of both reduced hematocrit and temperature on the activated clotting time assay. In contrast, whole blood heparin measurements correlate well with plasma heparin concentration before and during bypass. Further studies are needed to determine whether maintaining heparin levels during cardiopulmonary bypass by monitoring heparin concentration is more effective in preventing consumptive activation of the hemostatic system, reducing bleeding, and minimizing the use of blood products after cardiopulmonary bypass when compared with a protocol based on activated clotting time.

Blood Coagulation↗

Prospective evaluation and clinical utility of on-site monitoring of coagulation in patients undergoing cardiac operation.

Although laboratory coagulation tests permit a rational approach to both diagnosis and management of coagulation disorders after cardiopulmonary bypass, their clinical utility is limited by delays in obtaining results. This study was designed to evaluate prospectively the impact of on-site coagulation testing on blood product use, operative time, and intraoperative management of microvascular bleeding. Patients who underwent cardiac procedures involving cardiopulmonary bypass and subsequently developed microvascular bleeding were randomly assigned to receive either standard therapy (n = 36) or therapy defined by a treatment algorithm based on results from an on-site coagulation monitoring laboratory (n = 30). No differences were found between treatment groups in hematologic assay data, operative procedures, or duration of cardiopulmonary bypass. Patients treated in accordance with on-site laboratory results (algorithm therapy) received significantly less intraoperative fresh frozen plasma (0.4 +/- 1.1 U versus 2.4 +/- 2.8 U; p = 0.0006) during the treatment interval, had shorter operative times, and had less mediastinal chest tube drainage during the initial perioperative interval (158 +/- 169 ml versus 326 +/- 258 ml; p = 0.003) than did patients in the standard therapy group. Patients who underwent algorithm therapy also received fewer platelet (1.6 +/- 5.9 versus 6.4 +/- 8.2 U; p = 0.02) and red blood cell (1.9 +/- 1.7 U versus 4.1 +/- 4.1 U; p = 0.01) transfusions after the operation. Nine of 36 (25%) standard group patients received initial therapy which differed from that which would have been guided by the on-site algorithm protocol. Our findings indicate that rapid and accurate coagulation test results can guide specific therapy and optimize treatment of microvascular bleeding in patients who undergo cardiac operations.

Blood Coagulation Tests↗

Results of a rubella screening program for hospital employees: a five-year review (1986-1990).

The Barnes Hospital Employee Health Service (St. Louis, Missouri) rubella screening program was evaluated over the 5-year period between January 1, 1986, and December 31, 1990. A total of 6,969 new employees were hired, and 6,115 (87.7%) were screened for evidence of rubella immunity by the Employee Health Service. Rubella serology was performed on 5,893 (96.4%) of the screened employees, while 222 (3.6%) had documentation of prior rubella vaccination or rubella infection. The absence of immunity was identified in 325 employees or 5.3% of all those screened. Women were more frequently screened by the Employee Health Service than were men (p < 0.0001), and blacks were more frequently screened than were non-Hispanic Caucasians (p < 0.0001). Physicians were less frequently screened than were other departmental groups (p < 0.0001). The rate of seronegativity for each year of hire varied from 4.45 to 6.76%, but these differences were not significant. Logistic regression analysis demonstrated that 5-year birth cohorts correlated significantly with serologic status. Employees born in 1960-1964 were least likely to be seronegative, and employees born in 1970 or later were most likely to be seronegative. Sex, race, and department group were not predictive of serologic status, although significant differences in results from different rubella assays were detected. Only 13.8% of seronegative employees were subsequently vaccinated by the Employee Health Service. This study demonstrates a lower seronegativity rate than did previous studies. It identifies groups of employees likely to escape rubella screening and low vaccination rates. It finds increasing seronegativity among employees born after 1964 that correlates with the reported increasing rates of rubella in the United States.

Adolescent↗

Symptomatic cytomegalovirus infection in renal transplant recipients given either Minnesota antilymphoblast globulin (MALG) or OKT3 for rejection prophylaxis.

To compare the impact of using Minnesota antilymphoblast globulin (MALG) versus the monoclonal antibody, OKT3, on the development of symptomatic cytomegalovirus (CMV) infection, we reviewed a cohort of 130 cadaveric renal transplant recipients enrolled in a prospective comparison of MALG versus OKT3 for rejection prophylaxis. Among the 112 patients at risk for CMV, prophylactic MALG was associated with an increased risk of symptomatic infection (relative hazard [rh] = 3.31; 95% confidence interval CI], 1.50 to 7.30; P = 0.003). Transplantation of kidneys from CMV-seropositive donors into CMV-seronegative recipients (rh = 5.22; 95% CI, 2.34 to 11.63; P = 0.00004), first transplantation (rh = 4.76; 95% CI, 1.06 to 21.3; P = 0.039), and acute rejection therapy (rh = 2.03; 95% CI, 0.98 to 4.21; P = 0.055) were also associated with an increased risk. Prophylactic MALG followed by treatment with any agent for acute rejection was strongly correlated with symptomatic CMV infection (rh = 4.46; 95% CI, 3.71 to 5.21; P = 0.00006). Symptomatic CMV infection was not only more frequent, but more severe in recipients of prophylactic MALG, and more MALG recipients were treated with ganciclovir. There was no difference in rejection rate for the two rejection prophylaxis regimens (P = 0.625). Prophylactic OKT3 results in less risk of symptomatic CMV infection than prophylactic MALG in cadaveric renal transplant recipients who are seropositive for CMV or whose donors are seropositive for CMV.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Exclusion of chromosomal mosaicism in amniotic fluid cultures: efficacy of in situ versus flask techniques.

Accurate diagnosis of mosaicism in amniotic fluid cell cultures represents a major problem. If insufficient cells are analysed, true fetal mosaicism may go undetected. False-positive diagnosis is also possible since a second cell line may arise in vitro and not reflect the true fetal genetic constitution. These difficulties apply to both flask and in situ culture techniques, to varying degrees. The relative accuracy of flask versus in situ culture techniques in excluding mosaicism was determined by statistical analysis of experimental data from ten pairs of mixed male-female amniotic fluid specimens. The data support the idea that the majority of in situ colonies are independent of one another. The following conclusions are drawn: (1) analysis of a single metaphase from a number of different colonies enhances the confidence for excluding mosaicism; (2) analysis of more than one cell per colony offers little advantage; (3) exclusion of a given level of mosaicism requires analysis of fewer metaphases using the in situ method; (4) the confidence for excluding mosaicism is high with both in situ and flask techniques, using the provided guidelines; and (5) it is shown that the two-stage approach used by many laboratories is currently the most efficient way to exclude mosaicism.

Amniotic Fluid↗

Time-series analysis of myoelectric cycling of sphincter of Oddi: evidence of cycling during fed state.

The sphincter of Oddi (SO) in the fasted opossum exhibits spontaneous cyclic spikeburst activity that is temporally related to the interdigestive migrating myoelectric complex (MMC) of the small intestine. After feeding, the cyclic activity is apparently disrupted. Our aim was to use time-series analysis to mathematically describe the periodic behavior of the fasted state and to determine whether this periodicity is present after feeding. Five opossums were chronically prepared with bipolar electrodes secured to the SO. With the animals fasted and conscious, myoelectric activity was recorded for at least two MMC cycles after which they were fed 170 kcal of cream. Spikeburst frequency data were analyzed by fast Fourier transform (FFT) and by digital band-pass filtering. Results from FFT analysis showed an intense low-frequency peak during the fasted state which persisted but was markedly depressed during the fed state. Analysis of the data after filtering also showed persistent sinusoidal activity at the MMC frequency after feeding, although the waveform was significantly depressed by both peak-to-peak amplitude and root mean square amplitude analysis. Recovery to normal fasting cyclic behavior with recovery of both FFT and filtered data was observed. We conclude that in the opossum the cyclic nature of the SO myoelectric activity observed during the fasted state persists after feeding, but is inhibited and masked by an increase in overall spikeburst activity.

Ampulla of Vater↗

The effect of prescribed daily dose frequency on patient medication compliance.

The objective of this study was to determine the relationship between prescribed daily dose frequency and patient medication compliance. The medication compliance of 105 patients receiving antihypertensive medications was monitored by analyzing data obtained from special pill containers that electronically record the date and time of medication removal. Inaccurate compliance estimates derived using the simple pill count method were thereby avoided. Compliance was defined as the percent of days during which the prescribed number of doses were removed. Compliance improved from 59.0% on a three-time daily regimen to 83.6% on a once-daily regimen. Thus, compliance improves dramatically as prescribed dose frequency decreases. Probably the single most important action that health care providers can take to improve compliance is to select medications that permit the lowest daily prescribed dose frequency.

Antihypertensive Agents↗

Antimicrobial misuse in patients with positive blood cultures.

PURPOSE: Inappropriate antimicrobial use was examined among a randomly and prospectively selected cohort of patients with at least one positive result of blood cultures. This misuse was then analyzed with respect to hospital charges and length of stay (LOS). PATIENTS AND METHODS: The study consisted of 70 patients (average age, 58.5 years) who had not undergone bone marrow transplantation. Patient charts were reviewed daily for the following information: clinical signs and symptoms of infection, pertinent laboratory data, culture results, detailed data on each antimicrobial in every antimicrobial regimen and their appropriateness, hospital charges, LOS, diagnostic and procedure codes, and discharge status. Three severity of illness variables were generated. Inappropriate antimicrobial use was described according to one of 12 categories. RESULTS: The percent of antimicrobial misuse, defined as the proportion of days of administration of antimicrobials on which one or more antimicrobials were judged inappropriate, was found to be 22.3%. After adjustment for severity of illness and diagnosis, this average inappropriateness correlated with 4.2 additional hospitalization days and $5,368 additional hospital charges. CONCLUSION: Our results cannot distinguish among several possible reasons for these associations, including direct causality (e.g., toxicity and prolonged hospitalization for antimicrobial use) and indirect links such as inappropriate utilization of other resources and influences of severity of illness on antimicrobial use not accounted for in our equations. Nevertheless, the magnitude of the association gives import to the desirability of further studies.

Anti-Infective Agents↗

Effect of pedaling rate on submaximal exercise responses of competitive cyclists.

This investigation was undertaken to determine the effect of pedal frequency on submaximal exercise responses. Seven well-trained competitive cyclists were studied riding their road-racing bicycles on a motor-driven treadmill at 80% of maximum O2 consumption (VO2 max) using different gear ratios. Cyclists were also studied during a series of unloaded trials to assess the effects of varying rates of limb movements independent of external work load. Heart rate (HR) increased, whereas net HR (after subtracting the HR during unloaded cycling) decreased with increasing pedal frequency during loaded cycling. Expiratory flow (VE), O2 consumption (VO2), blood lactate, net VO2 (after subtracting the VO2 of unloaded cycling), and net VE (after subtracting the VE during unloaded cycling) were quadratically related to pedal frequency. The quadratic relationships evident after corrections were made for the additional work needed to move the legs more frequently may be explained at the lower pedaling rates by a less uniform pattern of blood flow caused by increasing the force requirement per pedal stroke and, at the higher pedal frequencies, by the recruitment of additional musculature to stabilize the trunk. The average of preferred frequency for the group, which was also the most economical pedaling rate judged by most of the variables was 91 rpm, although the preferred pedaling rate for each subject ranged from 72 to 102 rpm.

Heart Rate↗

The effect of medication compliance on the control of hypertension.

The effect of medication-taking patterns on blood pressure was investigated in 24 hypertensive outpatients being treated with once-daily doses of hydrochlorothiazide or chlorthalidone. Medication-taking patterns were measured with a small pill dispenser that electronically records the time of medication removal. Blood pressure reduction was found to correlate better with the total number of doses the patient removed from the pill pack during a month than with any of four other compliance measures that were based on the timing of dose removal. Analysis also suggested that blood pressure is improved if patients ingest omitted doses to "catch up" to the prescribed regimen. It is concluded that a simple pill count may be the most clinically relevant definition of compliance for patients with hypertension being treated with only hydrochlorothiazide or chlorthalidone, and that such patients should ingest all prescribed doses, regardless of the time interval between doses.

Aged↗

Antibiotic misuse in two clinical situations: positive blood culture and administration of aminoglycosides.

Antibiotic use was examined among randomly and prospectively selected cohorts of 79 patients with a positive blood culture and 88 patients given aminoglycosides for a variety of reasons. Appropriateness of antibiotic use was judged daily for each agent according to specific criteria of misuse. For patients with a positive blood culture, 14.3% of antibiotic-days were judged inappropriate in some regard, while for patients given aminoglycosides, 10.2% of antibiotic-days were thought to be inappropriate. The patterns of misuse were similar for the two groups despite disparate selection criteria. The unnecessary use of antibiotics was the single most common type of misuse in both groups, but errors in dosing collectively accounted for nearly one-half of antibiotic misuse. These results suggest that a variety of factors are responsible for misuse of antibiotics. Although the data presented do not allow conclusions about the optimal methods for control of antibiotic misuse, they imply that a multifaceted approach is probably required.

Ampicillin↗