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PubMed1981

[Prognostication of foetal weight by means of ultrasonic foetometry. Study into accuracy of various formulae and analysis of error sources (author's transl)].

The author conducted a large-scale study into all accessible formulae for foetal weight assessment on the basis of ultrasonic measurement. Included were the author's own recently devised formulae. They were all studied for their accuracy, with reference being made to 100 unselected data groupings.--Another analysis was made for the purpose of finding out the extent to which the number of data used by different examiners could change differences between estimated results derived from formulae. Reference in great detail is made also to the effects of measurement errors and selection of data upon formula results.--Proper choice of measurement level was found to be important. Abdominal parameters proved to be superior to thoracic parameters. Estimated results, generally, improved along with the number of foetal measuring points, provided they were really relevant and weightful.--Discussed is the relative value which should be ascribed to all factors with impact on the accuracy of weight prognosis. Proper choice of an adequate mathematical model or adjustment of such choice to foetal data is considered to be essential, because it has to be made by optimum consideration of all factors.--All the above formulae were verified, but accuracies claimed earlier by original authors were reproducible only in some rare cases. The demand, therefore, is made that whenever new formulae are introduced the best of all available techniques of assessment should be used to compare their results, with reference to be made to the same, unselected patients. This is considered to be the best way for an objective assessment of their advantages.--An account is given of those practicable formulae which can be recommended, as a result of the comparison, and for which easy-to-use nomograms are available.

Anthropometry↗
PubMed2003

A preoperative nomogram identifying decreased risk of positive pelvic lymph nodes in patients with prostate cancer.

PURPOSE: We developed a preoperative nomogram for prediction of lymph node metastases in patients with clinically localized prostate cancer. MATERIALS AND METHODS: The study was a retrospective, nonrandomized analysis of 7,014 patients treated with radical prostatectomy at 6 institutions between 1985 and 2000. Exclusion criteria consisted of preoperative androgen ablation therapy, salvage radical prostatectomy and pretreatment prostate specific antigen (PSA) greater than 50 ng/ml. Preoperative predictors of lymph node metastases consisted of pretreatment PSA, clinical stage (1992 TNM) and biopsy Gleason sum. These predictors were used in logistic regression analysis based nomograms to predict the probability of lymph node metastases. RESULTS: Overall 5,510 patients with complete clinical and pathological information were included in the study. Lymph nodes metastases were present in 206 patients (3.7%). Pretreatment PSA, biopsy Gleason sum, clinical stage and institution represented predictors of lymph node status (p <0.001). Bootstrap corrected predictive accuracy of the 3-variable nomogram (clinical stage, Gleason sum and PSA) was 0.76. Inclusion of a fourth variable, which accounts for institutional differences in lymph node metastases, yielded an area under the receiver operating characteristics curve of 0.78. The negative predictive value of our nomograms was 0.99 when they predicted 3% or less chance of positive lymph nodes. CONCLUSIONS: Using clinical information, we produced 2 calibrated and validated nomograms, which accurately predict pathologically negative lymph nodes in men with localized prostate cancer who are candidates for radical prostatectomy.

Adult↗
PubMed1985

[Normal nomogram of the pulmonary artery].

With the aim to establish quantitative characteristics of the pulmonary artery in order to use them in planning operations on congenital heart diseases, the data of morphometric investigations on the pulmonary artery has been studied in 83 hearts of newborns, children and mature persons died from causes not connected with any cardiovascular disorders. The regression equations are calculated; they reflect certain dependence between the quantitative characteristics of the pulmonary artery and the area of the body surface.

Adolescent↗
PubMed1977

Methods for determining the proliferation kinetics of cells by means of 5-bromodeoxyuridine.

After treatment of cells with 5-bromodeoxyuridine (BUdR), the percentage of completely BUdR-labelled interphase nuclei is greater the longer the BUdR treatment. The labelling effect is visible after staining with the fluorochrome 33258 Hoechst and with Giemsa. Various formulae and a nomogram are presented by means of which the percentage of cells in S period, duration of the S period and the whole cell cycle can be determined by examination of a single preparation or by comparison of several preparations. The methods are tested using cell cultures of Microtus agrestis and compared with autoradiographic methods after labeling with 3H-thymidine.

Animals↗
PubMed2000

Foot length in fetuses with abnormal growth.

Sonographic fetal foot length is highly predictive of gestational age. In order to assess the reliability of this parameter in predicting gestational age in cases of abnormal fetal growth, we examined fetal foot length in small- and large-for-gestational-age fetuses. A nomogram of foot length versus gestational age between 15 and 37 weeks was constructed using cross-sectional data obtained from 5372 singleton fetuses. Fetal foot lengths for small-for-gestational-age fetuses (estimated fetal weight below the 10th percentile) and large-for-gestational-age fetuses (above the >90th percentile) fetuses were plotted against the foot length nomogram in order to determine the number of small-for-gestational-age fetuses and large-for-gestational-age fetuses with foot lengths below the 10th and above the 90th percentiles, respectively. Of the 586 small-for-gestational-age fetuses, 355 (60.6%) had foot lengths below the 10th percentile on the nomogram. When foot lengths from large-for-gestational-age fetuses were plotted on the foot length nomogram, 29.4% (219 of 744) had measurements above the 90th percentile. Fetal foot length can be influenced by growth restriction as well as states of accelerated fetal growth. Our findings imply that there are limitations to the use of fetal foot length for gestational age assessment, particularly in fetuses with growth abnormalities.

Female↗
PubMed1983

Pharmacokinetics of aztreonam in patients with various degrees of renal dysfunction.

We have studied the pharmacokinetics of 1-g intravenous doses of aztreonam in four groups of six volunteers each, distinguished by their creatinine clearances (greater than 80, 30 to 80, 10 to 29, and less than 10 ml/min). Subjects received 1 g of aztreonam intravenously without any complications. Aztreonam serum and urine levels were measured by microbiological methods and by high-pressure liquid chromatography, and unbound serum aztreonam was determined by ultrafiltration. Serum levels were well described by a two-compartment infusion model. From this model we determined steady-state volume of distribution, alpha distribution phase half-life, beta elimination phase half-life, and total clearance of aztreonam. The mean of beta elimination phase half-life ranged from 2 h in normal subjects to 6 h in anephric patients. The total clearance of aztreonam correlated closely with corrected creatinine clearance calculated from serum creatinine, age, and sex (r = 0.97, P less than 0.001) and ranged from a mean value of 107 ml/min in normal subjects to 29 ml/min in functionally anephric patients. Some 75% of aztreonam excretion was renal. Urinary recovery of aztreonam ranged from 58% of the administered dose in normal subjects to 1.4% in uremic patients. Free aztreonam in serum correlated inversely with creatinine clearance (P less than 0.001). A nomogram was developed as a guide for adjustment of aztreonam dosage according to renal function.

Adult↗
PubMed1990

A set of simple aids to drug dosage adjustment in renal insufficiency.

A set of graphical aids to drug dosage adjustment is presented, consisting of 1) a nomogram for evaluation of the dosage adjustment factor, 2) a nomogram for estimation of the creatinine clearance from the serum creatinine level, 3) decision tables for selection of a clinically acceptable adjustment of the dosing regimen. The set is accompanied by a list of percentage fractions excreted unchanged in urine for selected drugs and requiring adjustment of the dosing regimen in renal insufficiency. An example of the utilization of the set is demonstrated in comparison with the usual procedures of dosing regimen adjustment.

Creatinine↗
PubMed1982

Dosing implications of altered gentamicin disposition in patients with cystic fibrosis.

A pharmacokinetic approach was used for gentamicin dosing in 19 children and young adults with cystic fibrosis. A one-compartment open-model analysis of steady-state gentamicin pharmacokinetics revealed a significantly larger apparent volume of distribution and total plasma clearance for patients with CF as compared to a similar population of children without the disease. The increase in the apparent volume of distribution for patients with CF produced a larger daily gentamicin dose requirement to maintain similar steady-state levels as compared to children without the disease. Significant differences in the elimination rate constant and half-life for gentamicin were not found between these populations. Linear correlations between creatinine clearance and kel for gentamicin, and total body body weight and the apparent volume of distribution were demonstrated for children with varying degrees of stable renal function but not patients with CF. Altered gentamicin disposition peculiar to CF precludes application of currently used dosing nomograms or guidelines derived from normal populations, and emphasizes the need for individualized gentamicin therapy guided by a pharmacokinetic approach in these patients.

Adolescent↗
PubMed1988

Altered aminoglycoside pharmacokinetics in the critically ill.

We studied prospectively 49 patients being treated in an intensive care unit with aminoglycosides for gram-negative sepsis. Pharmacokinetic data were calculated from three post-dose serum levels using a one-compartment model. Doses required to achieve peak levels between 5 and 10 mg/l with trough levels approximately 1.0 mg/l ranged between 2 and 12 mg/kg per day (mean dose 7 mg/kg per day). During therapy 60% of the patients had a change in their apparent volume of distribution (Vd) of greater than 20%. These patients were likely to have confirmed infection and to be febrile at the start of treatment. Two to three weeks after discharge ten patients were restudied after a single dose of aminoglycoside. There was a reduction in mean Vd from 0.24 to 0.18 l/kg (P less than 0.02). Critically ill patients have significantly larger volumes of distribution and may require larger doses per kilogram of body weight of aminoglycoside to achieve therapeutic concentrations. Due to considerable variation in kinetic parameters, the use of standard doses or dosing nomograms is not recommended.

Aminoglycosides↗
PubMedDate not supplied

Kinetics of cefsulodin in patients with renal impairment.

Kinetics of cefsulodin were determined after administration of a 500-mg dose to normal subjects and patients with various degrees of renal insufficiency, including those requiring hemodialysis. Elimination kinetics were described by a two-compartment model. The steady-state volume of distribution was 0.26 liters/kg regardless of renal function. When the glomerular filtration rate (GFR) was greater than 80 ml/min, the elimination half-life (t1/2) was 1.9 hr. When the GFR ranged from 79 to 53 ml/min, t1/2 was 2.9 hr. In patients with moderate renal failure, in whom the GFR was 32-22 ml/min, t1/2 was 5.7 hr. In anuric patients, t1/2 was 13.0 hr. During hemodialysis the average plasma flow was 122 ml/min, dialyzer plasma clearance was 50.9 ml/min, concentration of drug in plasma was reduced by 60%, and t1/2 decreased to 2.1 hr. After dialysis the elimination rate appeared to return to that found in subjects not undergoing dialysis. While progressive renal failure slows the elimination of cefsulodin, there is a linear relationship between elimination of cefsulodin and GFR such that dosage nomograms can be developed. In patients undergoing hemodialysis, the maintenance dose of cefsulodin should be reduced to 10% of normal, and 60% of the dose should be given after hemodialysis.

Adult↗
PubMed1995

The correlation of multichannel urodynamic pressure-flow studies and American Urological Association symptom index in the evaluation of benign prostatic hyperplasia.

PURPOSE: We correlated multichannel pressure-flow urodynamics and the American Urological Association (AUA) symptom index in the evaluation of benign prostatic hyperplasia. MATERIALS AND METHODS: We evaluated 121 consecutive, symptomatic patients older than 55 years with the AUA symptom score and multichannel pressure-flow urodynamic studies. Testing was performed during a single session and the data obtained from 103 patients were plotted on the Schäfer nomogram for assessment of outflow obstruction. Linear regression statistical analysis was used to determine correlations. RESULTS: There was no significant correlation between uroflowmetry and Schäfer curves (r = 0.173 to 0.326), uroflowmetry and AUA symptom scores (r = 0.134 to 0.153) and, most importantly, AUA symptom scores and Schäfer curves (r = 0.025 to 0.137). CONCLUSIONS: We conclude that these modalities measure independent variables, and should not be linked in the evaluation and treatment decision of the patient with prostatism.

Aged↗
PubMedDate not supplied

Hypothermia is an independent predictor of mortality in ruptured abdominal aortic aneurysms.

Hypothermia is known to significantly increase mortality in trauma patients, but the effect of hypothermia on outcomes in ruptured abdominal aortic aneurysms (RAAA) has not been evaluated. The authors reviewed their experience from 1990 to 1999 in 100 consecutive patients who presented with RAAA and survived at least to the operating room for surgical treatment. There were 70 men and 30 women, with a mean overall age of 74 +/-8 years. Overall mortality was 47%. Univariate ANOVA (analysis of variants) showed significant correlation with mortality for decreased intraoperative temperature, decreased intraoperative systolic blood pressure, increased intraoperative base deficit, increased blood volume transfused, increased crystalloid volume (all p < 0.001); decreased preoperative hemoglobin (p = 0.015); and increased age (p = 0.026). Patient sex, initial preoperative temperature, preoperative systolic blood pressure, and operating room time were not correlated with mortality in the univariate analysis. Using these same clinical variables, multiple logistic regression analysis showed only 2 factors independently correlated with mortality: lowest intraoperative temperature (p = 0.006) and intraoperative base deficit (p = 0.009). The mean lowest temperature for survivors was 35 +/-1 degrees C and for nonsurvivors 33 +/-2 degrees C (p < 0.001). When patients were grouped by lowest intraoperative temperature, those whose temperature was < 32 degrees C (n = 15) had a mortality rate of 91%, whereas patients with a temperature between 32 and 35 degrees C (n = 50) had a mortality rate of 60%. In the group that remained at or > 35 degrees C (n = 35) the mortality rate was only 9%. A nomogram of predicted mortality versus temperature was constructed from these data and showed that for temperatures of 36, 34, and 32 degrees C the predicted mortality was 15%, 49%, and 84%, respectively. The authors conclude that hypothermia is a strong independent contributor to mortality in patients with ruptured abdominal aortic aneurysms and that very aggressive measures to prevent hypothermia are warranted during the resuscitation and treatment of these patients.

Aged↗
PubMed1987

Doubling time of human chorionic gonadotropin (hCG) in early normal pregnancy: relationship to hCG concentration and gestational age.

There is controversy regarding whether the doubling time of human chorionic gonadotropin (hCG) in early normal pregnancy is constant or rises with increasing gestational age (GA) and hCG concentration. To clarify the influence of these variables on hCG doubling time, we obtained serial blood specimens every 2 to 4 days between postovulatory day 12 and 70 from 16 women who conceived while monitoring basal body temperature. The serum concentration of beta-hCG was determined by radioimmunoassay. Serial doubling time of hCG was calculated in all subjects and correlated with GA and hCG concentration. Least-squares estimates of 95% confidence bands were established from regression analysis given the second hCG concentration for each pair of samples or GA. For elimination of the need for calculation and thus improvement of the clinical utility of doubling time determinations, a nomogram relating the concentrations of hCG in paired serum samples to doubling time was constructed. We observed a significant correlation of doubling time with hCG concentration and GA, both in the group overall and within each individual pregnancy. These data support the recommendation that doubling time determinations should be evaluated with reference to normal values for a given GA or hCG concentration and suggest that previously proposed normal values of doubling time in early normal pregnancy may be low.

Chorionic Gonadotropin↗
PubMed2000

Cardiovascular risk changes after lipid lowering medications: are they predictable?

Changes in cardiovascular risk after lipid lowering medications are generally expressed as relative risk reduction (RRR). Comparison of the eight major studies published in this last decade indicates that the RRRs ranged from a minimum (19%) for the LRC Study with cholestyramine, to maximal values of 34-37% for studies such as the HHS, 4S and AFCAPS/TexCAPS. These RRRs were barely related to the drugs' effects on major lipid parameters, e.g. LDL cholesterol. Instead, by using the absolute risk reduction (ARRs), easily calculated by subtracting the percentage end points for the drug treated from these values of the placebo group in all studies, a wide range of values was found, also adding to the series a non pharmacological study such as the Program on the Surgical Control of the Hyperlipidemias (POSCH) trial. Calculated ARRs were directly correlated to the baseline cardiovascular (CV) risk in all studies, thus allowing an easy prediction of a drug's effect in the selected population. Drugs with different mechanisms (statins, fibrates and resins) all fitted into this correlation nomogram. These findings clearly indicate that the CV effects of lipid changes, such as LDL cholesterol and triglyceride reduction or HDL rises, are in the same direction, and can be well predicted. The similar, almost identical behavior of drugs affecting LDL cholesterolemia to a different degree or not at all, indicates that novel approaches should be sought to improve risk reduction and that individual therapy should be ideally pursued, rather than a 'one drug' approach.

Anticholesteremic Agents↗
PubMed2005

The prognostic value of a nomogram for exercise capacity in women.

BACKGROUND: Recent studies have demonstrated that exercise capacity is an independent predictor of mortality in women. Normative values of exercise capacity for age in women have not been well established. Our objectives were to construct a nomogram to permit determination of predicted exercise capacity for age in women and to assess the predictive value of the nomogram with respect to survival. METHODS: A total of 5721 asymptomatic women underwent a symptom-limited, maximal stress test. Exercise capacity was measured in metabolic equivalents (MET). Linear regression was used to estimate the mean MET achieved for age. A nomogram was established to allow the percentage of predicted exercise capacity to be estimated on the basis of age and the exercise capacity achieved. The nomogram was then used to determine the percentage of predicted exercise capacity for both the original cohort and a referral population of 4471 women with cardiovascular symptoms who underwent a symptom-limited stress test. Survival data were obtained for both cohorts, and Cox survival analysis was used to estimate the rates of death from any cause and from cardiac causes in each group. RESULTS: The linear regression equation for predicted exercise capacity (in MET) on the basis of age in the cohort of asymptomatic women was as follows: predicted MET = 14.7 - (0.13 x age). The risk of death among asymptomatic women whose exercise capacity was less than 85 percent of the predicted value for age was twice that among women whose exercise capacity was at least 85 percent of the age-predicted value (P<0.001). Results were similar in the cohort of symptomatic women. CONCLUSIONS: We have established a nomogram for predicted exercise capacity on the basis of age that is predictive of survival among both asymptomatic and symptomatic women. These findings could be incorporated into the interpretation of exercise stress tests, providing additional prognostic information for risk stratification.

Adult↗
PubMed2006

Prognostic impact of lymphovascular invasion in radical prostatectomy specimens.

OBJECTIVE: To estimate the prognostic value of lymphovascular invasion (LVI) in patients with node-negative prostate cancer treated by radical prostatectomy (RP). PATIENTS AND METHODS: In all, 412 patients with prostatic adenocarcinoma who had RP and pN0 status were analysed for all established standard pathological factors and LVI. The influence of these pathological findings on biochemical failure was evaluated by multivariate analysis with the Cox model. The mean (range) follow-up was 52.5 (10-116) months. RESULTS: LVI was identified in 42 patients (10.2%) and significantly associated with a high preoperative prostate-specific antigen (PSA) level, a high PSA density, high percentage of positive biopsy cores, high Gleason score, and seminal vesicle invasion. Of the 42 patients with LVI, 33 (79%) had a Gleason score of > or = 7 and 27 (64%) had pathological stage pT3. The 5-year biochemical-free survival was 87.3% for patients with no LVI and 38.3% with LVI on the RP specimen (P < 0.001). By multivariate analysis, LVI and Gleason score were independent predictors of biochemical failure. CONCLUSION: These results show that in addition to the Gleason score, only LVI is strongly correlated with biochemical failure after RP. These findings support the routine evaluation of LVI status in RP specimens and provide the option for its incorporation into nomograms predictive of oncological outcome.

Adenocarcinoma↗
PubMed1988

Measurement of end-capillary PO2 with positron emission tomography.

The analysis of positron emission tomography measurements of oxygen metabolism has been extended to provide a quantitative estimate of end-capillary PO2. The principle of this extension rests on the idea that the oxygen extraction fraction can be used to calculate the end-capillary oxygen saturation of the blood. The relation between oxygen saturation and PO2 is obtained through the oxygen dissociation curve. Our studies show that in addition to the local oxygen extraction fraction, arterial PO2 and pH values are needed in the calculation, whereas fairly large variations in factors such as PCO2, hematocrit, hemoglobin, and plasma protein levels have little or no effect. Rough estimates of end-capillary PO2 can be made using standard O2 dissociation nomograms. Blood gas and acid-base properties of blood have been known for decades, making it possible to account accurately for individual differences that may be encountered when studying patients. Measurements in nine normal subjects yielded a mean end-capillary PO2 value of 31.2 mm Hg. The ability to make a quantitative visualization of altered patterns of end-capillary PO2 provides an additional dimension to the investigation of stroke disease and tumor metabolism.

Blood Gas Analysis↗
PubMed1989

Body surface area of Africans: a study based on direct measurements of Nigerian males.

Direct measurement of body surface area (Ab) was made on 20 male adult Nigerians of African descent by coating and planimetry. The results were compared with estimated Ab values obtained using six widely accepted height and weight prediction equations. The results show that existing formulas do not predict surface areas of our subjects accurately. Measured Ab values of our subjects were 6-22% greater than predicted values obtained from non-African nomograms. Using these results, we computed new variables for height and weight formulas that accurately predict the surface area of Africans. The closest fit to measured values is given by the equation Ab(m2) = 0.001315 x Height 1.2139 (cm) x weight 0.2620 (kg) +/- 0.04815 (SEE). The new variables are significantly different from those of existing equations. Our height variable is several times greater than the weight variable and reflects a greater importance of height than weight in determining the surface area of Africans than is the case with Caucasians.

Adult↗