Decrease in the number of abdominal hysterectomies after introduction of laparoscopic hysterectomy.

STUDY OBJECTIVE: To compare two 3-year periods before and after laparoscopic hysterectomy was introduced into our resident training program. DESIGN: Retrospective analysis (Canadian Task Force classification II-2). SETTING: Teaching hospital in the Netherlands. PATIENTS: Women undergoing hysterectomy from 1992 to 1994 and 1995 to 1997. INTERVENTION: Abdominal, vaginal, and laparoscopic hysterectomies. MEASUREMENTS AND MAIN RESULTS: Laparoscopic hysterectomy significantly (p<0.002) reduced the number of abdominal hysterectomies. CONCLUSION: To reduce the number of abdominal hysterectomies, it is essential that the laparoscopic procedure be taught to residents.

Haemodynamic changes during laparoscopic anterior fundoplication measured by trans-oesophageal Doppler ultrasound.

We investigated the cardiovascular effects of pneumoperitoneum and steep head-up tilt during laparoscopic fundoplication using an intra-oesophageal Doppler ultrasound probe. Repositioning of the probe proved sufficient to maintain the signal throughout the procedure despite the pneumomediastinum. There was a statistically significant increase in mean arterial blood pressure and a fall in stroke distance but not in systemic vascular resistance. Increasing or decreasing the blood pressure with drugs improved stroke distance. The oesophageal Doppler ultrasound proved a satisfactory method for assessing cardiovascular changes during fundoplication.

Focal vulvitis: a psychosexual problem for which surgery is not the answer.

In the last decade focal vulvitis has been identified as a distinct syndrome, characterized by unexplained burning vulvar pain and superficial dyspareunia. A 'Woodruff perineoplasty' has been recommended as a treatment method. A research project was conducted, investigating the long-term results of surgical treatment and the etiology of focal vulvitis. Results showed that the great majority of women continued to suffer from focal vulvitis after the operation, which leads to the conclusion that the procedure should be abandoned. Retrospective data revealed several immediate causes of mechanical and chemical irritation of the vulva. All women exhibited 'inadequate sexual behavior': having intercourse without a sufficient amount of lubrication and/or in the presence of hypertonia of the pelvic floor. Psychosexual processes were further characterized by deterioration of sexual and general well-being, resulting in lack of libido and depression, which contributed considerably to the problem. An integrated approach to treatment is recommended, which incorporates protection of the vulvar skin, relaxation of pelvic muscles and sexological treatment of the psychosexual and relational aspects.

[Expectant management in extrauterine pregnancy is possible]. / Afwachtend beleid bij buitenbaarmoederlijke zwangerschap mogelijk.

Twenty-nine patients with presumed ectopic pregnancies, who visited the Onze Lieve Vrouwe Gasthuis outpatient clinic in Amsterdam between January 1990 and July 1991, received expectant management because of mildness of the symptoms. Five patients were shown to have a non-intact intrauterine pregnancy. Only three of the remaining 24 patients needed surgery because of increasing serum HCG concentrations and (or) complaints. Our results therefore indicate that with declining HCG levels and mild symptoms, regardless of the HCG level at presentation, expectant management is justified.

[Are earlier birth weights different from current ones?]. / Verschillen de geboortegewichten van vroeger en nu?

A sample was taken from non-pathological Caucasian births in Amsterdam from 1972 until 1982. The methods replicated as closely as possible those applied by Kloosterman to births from 1931 until 1967 for the Amsterdam Growth Curves. Birth weight percentiles and confidence intervals were determined non-parametrically in groups distinguished by sex, order of birth and duration of pregnancy. The correlations among the weekly means and the extreme percentiles were tested from the 36th to the 43th pregnancy week. We found a strong correlation (r = 0.983) between our sample and the Amsterdam Growth Curves. The means in the latter sample exceeded ours by 48.5 grammes which equals the estimated clerical error of the birth weights of 50 grammes. There is no strong evidence that the birth weights have changed much in the Caucasian part of the Amsterdam population.

Is maternal whole blood viscosity a factor in fetal growth?

Many authors have correlated changes in maternal hemodynamics during pregnancy with fetal growth. Sufficient plasma volume expansion in pregnancy seems mandatory for an optimal reproductive result. A correlation between rheological characteristics (low-shear whole blood viscosity and yield shear stress) and birthweight centiles was found in 26 third-trimester pregnancies. The level of statistical significance (P less than 0.05) was reached in nulliparous pregnancies but not in parous pregnancies. Measurements of whole blood viscosity at low shear rate and yield shear stress seem to provide information on the efficacy of placental perfusion. There have been reports in the literature to support the assumption of the prevalence of low-shear circumstances in the intervillous space. The hypothesis is put forward that, during pregnancy, the changes in maternal hemodynamics influence fetal growth by their impact on the flow through the placenta.

Effect of calibration material lot changes on results for the "SMAC".

The effect of two changes of calibration material (separated by five months) for the SMAC continuous-flow analyzer was followed by means of five quality-control indices: three normal and abnormal control sera, the mean of the central 50th percentile of patients' results, and the mean value for normal individuals. After the first and second changes of calibration materials, eight and six, respectively, of the 20 different tests exhibited statistically significant changes as shown by the indices. The cumulative shift for two of the 20 tests was considered medically significant. Prospective studies on split samples of patients' sera before the change in calibration material only predicted half the significant changes in test results later evidenced by the above-mentioned indices.

Workload, space, and personnel of microbiology laboratories in teaching hospitals.

The resources needed to operate a microbiology laboratory are known only as rough approximations. In order to gather more information about these resources, a 13-page questionnaire was completed by 50 pathology departments, of which 38 departments provided adequate information about their microbiology sections to permit data analysis. This study reports the results for resource and work load factors and significant regression analyses among these factors for the whole microbiology section and the subsections of aerobic bacteriology, anaerobic bacteriology, mycobacteriology , mycology, parasitology, virology, and antibiotic sensitivity. These data provide a basis for evaluating the current needs of microbiology laboratories and for making projections for the future.

Workload, space, and personnel of hematology laboratories in teaching hospitals.

The resources needed to operate a hematology laboratory are known only as rough approximations. To gather more information about these resources, a 13-page questionnaire was completed by 50 pathology departments, of which, 34 departments provided adequate information about their hematology sections to permit data analysis. This study reports results for resource and work load factors and significant regression analyses among these factors for the whole hematology section and the subsections of coagulation, special hematology, and bone marrow examination. These data provide a basis for evaluating the current needs of hematology laboratories and for making projections for the future.

Predicting space and personnel in academic clinical pathology.

This report compares the results from two surveys of the resources of academic clinical pathology departments. In 1971, the Academy of Clinical Laboratory Physicians and Scientists (ACLPS) obtained data from 25 academic clinical pathology departments on actual workload variables (census, procedures per year, admissions per year, and outpatient visits per year), along with estimates of ideal space and ideal staffing. A study conducted by NIH obtained data from 31 academic clinical pathology departments for 1976 for the same workload variables, along with actual and ideal space and actual staffing. Regression analyses were performed with space, technical personnel, and doctoral personnel as the dependent variables and patients per day, admissions per year, and numbers of procedures per year as the independent variables. For each study, admissions per year and patients per day were statistically significant predictors of both departmental space and technical personnel. The slope of each significant regression from the ACLPS study was greater than the comparable significant slope from the NIH study. These data provide a basis for comparing resources among academic clinical pathology departments, assessing current resources, and projecting future needs.

Workload, space, and personnel of clinical chemistry laboratories in teaching hospitals.

The resources needed to operate a clinical chemistry laboratory are known only as rough approximations. In order to gather more information about these resources, a 13-page questionnaire was completed by 50 pathology departments of which 38 departments provided adequate information about their clinical chemistry section to permit adequate data analysis. This study provides the results for resource and workload factors, and significant regression analyses among these factors for the whole clinical chemistry section and the subsections of general chemistry, urinalysis, endocrinology, enzymology, lipid analysis, and toxicology. These data provide a basis for evaluating the current needs of clinical chemistry and for making projections for the future.

Quantitation of pathogenic potential of Staphylococcus aureus.

Numerical estimates of the pathogenicity of Staphylococcus aureus strains were made for phage-typed strains from a relative incidence of significant to nonsignificant isolates from hospital patients. For a specific phage-patterned strain, the number of isolates from significant (wounds, abscesses, blood, etc.) sites was divided by the number of isolates from nonsignificant (respiratory tract, body surfaces, etc.) sites. This value, multiplied by 100, was the index of infection potential (IIP). IIP values for the S. aureus strains studied ranged from a low of 8 to a high of 50. The average IIP for all phage-patterned strains that occurred 50 or more times was 20. There was an inverse relationship between length of the phage pattern (number of the 26 typing phages that lysed the strain) and pathogenicity. Those strains with shorter phage patterns had higher IIP values and were more pathogenic. Strains lysed by one phage had an average IIP of 27, whereas those lysed by 18 phages had an average IIP of 14.

Lactate dehydrogenase activity as measured by the SMAC is related to flow-cell energy.

Determination of lactate dehydrogenase (LDH) activity in the SMAC (Technicon) is based on the change in NADH absorbance between two flow cells. We noted that results for patients' specimens and controls changed when the fiber optic terminations for the two LDH channel flow cells were adjusted or "peaked" at the colorimeter chopper assembly. The energy (intensity) of light reaching the flow cells was varied by adjusting the fiber optic terminations, and the absorbance readings for a series of solutions containing NADH and patients' specimens were recorded. For both flow cells, when the fiber optic terminations were adjusted to increase the zero absorbance light intensity from 20 lines to 60 lines, a significant (p less than 0.0001) proportional change was seen in the absorbance readings. Evidently the difference in absorbance between the two flow cells is related not only to the NADH concentrations but also to the difference in the light intensity at the two flow cells. Consequently, changes in the adjustment of the fiber optic terminations produce systematic changes in results for LDH in patients' sera. These systematic changes in LDH results may be minimized by maintaining equivalent settings of the fiber optic terminations for the two flow cells and by using the calibration material with an absorbance most similar to that of patients' specimens.

Why we need better test evaluations.

A laboratory test is clinically useful only if it successfully answers a question of consequence to patient management. Unfortunately, the results and conclusions of many published test evaluations are misleading or of uncertain validity because common-sense principles of study design are overlooked. This is illustrated by examples from recent literature. We suggest that tests should be evaluated with prospective studies of patients representative of the population for which the test will ultimately be used. The clinical question to be addressed by the test should be clearly stated, and then answered for each patient by means independent of the test being evaluated. When comparing tests with each other, decision levels should be chosen to give either the same sensitivity or specificity for each. The use of soundly designed protocols for the clinical evaluation of tests provides the information needed to select the most effective tests.

Comparison of the effectiveness of four clinical chemical assays in classifying patients with chest pain.

We compared the usefulness of four serum assays for classifying patients originally suspected of having an acute myocardial infarction. One of these is the long-used measurement of total creatine kinase (CK) activity. The other three are relatively new immunoassays: myoglobin by RIA, CK-BB by RIA, and CK-MB by immunoinhibition. When we evaluated test effectiveness with use of conventionally derived reference ranges, the results were misleading. However, by using receiver operating characteristic curves, we were able to effectively compare the four tests at all possible decision levels, rather than at only one. Multiple closely sequential serum specimens were obtained during the first four days after the onset of chest pain. Total CK, CK-MB, and CK-BB all behaved similarly, reaching peak diagnostic effectiveness at 18-20 h, when all three correctly classified 95% of the infarct patients, with a zero false-positive rate. However, total CK was more useful in identifying infarcts later in their courses than were the two CK isoenzyme tests. Myoglobin assay was most effective earlier in the course, at about 7 to 8 h. Our results indicate (a) that the tests for myoglobin and for CK or its isoenzymes are complementary and (b) that of the three CK tests, measurement of total CK activity provides the most information over the broadest segment of a patient's course.