Principles of screening

Preventive medicine is an increasingly important area of clinical practice. Conceptually, preventive medicine involves three tasks of the clinician: screening, counseling, and immunization/prophylaxis. This opening article reviews some of the basic tenets underlying screening including basic epidemiologic principles, characteristics of a good screening situation, barriers to screening, and some of the potential hazards of screening.     

Noise in the signal-averaged electrocardiogram and accuracy for identification of patients with sustained monomorphic ventricular tachycardia after myocardial infarction

Late potentials are detected at various noise levels in clinicalstudies. The aim of this study was, in a case-control design,to assess the effect of residual noise level on the identificationof patients with sustained monomorphic ventncular tachycardiaafter myocardial infarction. Electrocardiograms from 16 patientswith prior myocardial infarction and documented sustained monomorphicventricular tachycardia and 41 patients with prior myocardialinfarction and without ventncular tachycardia, were analysedby two signal averaging procedures to noise level 0·2and 0·4 µV Standard time domain parameters weremeasured. Two definitions of late potential were analysed: (1)if any two of the following criteria were present (signal-averagedQRS duration >120 ms, late potential duration >40 ms,and root-mean-square voltage of the terminal 40 ms of the filteredQRS <25µV); or (2) if the signal-averaged QRS duration120 ms. Overall the signal-averaged electrocardiogram performedbetter at noise level 0·4µV compared to noise level0·2µV with respect to identification of patientswith or without ventricular tachycardia after myocordial infarction.Reducing noise level from 0·4 to 0·2 µVincreased the sensitivity, but the consequence was a substantialdecrease in specificity. Our data indicate that when a highsensitivity is the goal, the definition based only on signal-averagedQRS duration 120 ms should be applied; sensitivity was 88% andspecificity 59% at noise level 0·4 µV. If a highspecificity is the goal, the definition should be based on thedefinition with two abnormal parameters; sensitivity was 69%and specificity 68% at noise level 0·4µV.     

Definition of inseparably fused ventricular myocardium in thoracopagus: Fetal echocardiographic utility and pathologic refinement

Summary Correlative echocardiographic and pathological findings in a thoracopagus with conjoined hearts are reported. One twin had tricuspid atresia with discordant atrioventricular connections and concordant ventriculoarterial connections. The morphologic right ventricle was hypoplastic and there was a large muscular ventricular septal defect. The other twin had hypoplasia of the mitral valve anulus and left ventricle with double-outlet right ventricle and pulmonary valve atresia. The tricuspid valve was severely insufficient in part because of a large orifice and redundant, elongated leaflets with abnormal chordal attachments. The left ventricles of these two twins shared a perforated common free wall with at least two large defects allowing mixing of the circulations at that level. Not all anatomic details were established conclusively by fetal echocardiography; however, sufficient diagnostic information was obtained to support a decision not to aggressively resuscitate these twins after elective cesarean delivery at 31 weeks' gestation.     

Bone cysts and spontaneous fractures in two siblings with dyskeratosis follicularis Darier.

Two siblings with Darier's disease, multiple bone cysts and recurrent "spontaneous" fractures are described.     

Evolving a blueprint for certification: the responsibilities and knowledge comprising American professional oncology nursing practice.

Ensuring adequate content validity of a certification examination is a major concern in the development and administration of a test. To establish content validity of the Oncology Nursing Certification Corporation (ONCC) certification exam, a job analysis study was conducted to provide empirical data about the responsibilities and knowledge areas required for practice at the level of the newly certified oncology nurse. The study involved The Profession of Oncology Nursing: An Inventory of Responsibilities and Knowledge (IRKPON), a questionnaire that was developed based on a review of the literature, professional practice information, interviews with oncology nurses, the original ONCC certification exam table of specifications, and evaluations undertaken by two advisory committees. The IRKPON consisted of three parts: 56 responsibilities clustered into eight job dimensions, 217 knowledge areas grouped into seven knowledge dimensions, and demographic information. The IRKPON was sent to a stratified random sample of 3,000 oncology nurses in the United States, who were asked to rate both the responsibilities and knowledge areas by level of importance. The 1,297 (43%) responding nurses rated 45 of 56 responsibilities (80.4%) as "very important" and 8 of 56 responsibilities (14.3%) as "extremely important"; they also rated 163 of 217 knowledge areas (75.1%) as "very important" and 41 of 217 knowledge areas (18.9%) as "extremely important." These findings identified the specific responsibilities most important to the oncology nurse role at the level of the newly certified nurse, as well as the knowledge areas necessary for competent performance. Subsequent ONCC certification examinations were modified; the test blueprint that guides the construction of the examination was revised, and the passing score was adjusted.     

Fine structure of neutrophils from turpentine-induced pleuritis in mice, simulating rheumatoid arthritis cells.

Pleural effusions were made by intrapleural turpentine installation in mice. The fine structure of inflammatory cells from the effusions was normal except for lipid inclusions. The same type of inclusion was previously found in neutrophils from pleural effusions in patients with tuberculous infection, rheumatoid disease, or carcinomatosis. The lipid inclusions observed in neutrophils from an irritative turpentine-induced pleurisy should be considered as "fatty change", and are structurally similar to the rheumatoid arthritis cells seen in patients with different diseases.     

AHRA survey. Survey on job content and salary: Part III

Part III of the AHRA Statistical Resource Committee salary survey compares the AHRA data with other studies. Comparisons are also provided between AHRA data from 1984 to 1990, highlighting trends in salary and education level, annual increases, and job satisfaction.     

Desipramine and some other antidepressant drugs decrease the major norepinephrine metabolite 3,4-dihydroxyphenylglycol-sulphate in the rat brain

Summary The O-methylated and non-O-methylated end metabolites of norepinephrine (NE) in the rat brain were measured to investigate a presumed shift in metabolism of NE from intra- to extraneuronal metabolism by uptake inhibitory antidepressant drugs. Desipramine (DMI), protriptyline and maprotiline in doses from 2.5–20 mg/kg reduced the concentration of the major non-O-methylated NE metabolite 3,4-dihydroxyphenylglycolsulphate (DOPEG-SO₄) in the whole rat brain to about 60–70% of controls, while imipramine, amitriptyline, butriptyline and clorimipramine (20 mg/kg, 21/2 h) caused no significant decrease. The major O-methylated NE metabolite free plus conjugated 3-methoxy-4-hydroxyphenylglycol (total-MOPEG) was almost unaffected by all the drugs 21/2 h after administration. At longer time intervals, however, i.e. 5 h, a high dose of DMI (10 mg/kg, s.c.) decreased total-MOPEG to 75% of controls. DOPEG-SO₄ was decreased by DMI in all brain regions examined: cortex, hippocampus, cerebellum and brain rest. ³H-normetanephrine was increased 1/2h and 1 h after intraventricular injection of ³H-dopamine, and at the same time interval both total-³H-MOPEG and ³H-DOPEG-SO₄ were decreased. Amine storage in granules was not necessary for the action of DMI since DMI retained its metabolite-lowering effects in reserpinized rats. Inhibition of NE uptake in vivo did not induce the expected increase in the major extraneuronal NE metabolite MOPEG, but only the expected decreased in DOPEG-SO₄. The reduction of both the major NE metabolites by DMI suggests a decreased metabolism and turnover of NE.Abbreviations Used NE norepinephrine - DOPEG 3,4-dihydroxyphenylglycol - DOPEG-SO₄ DOPEG sulphate ester - MOPEG 3-methoxy-4-hydroxyphenylglycol - total-MOPEG free plus conjugated MOPEG - DOPAC 3,4-dihydroxyphenylacetic acid - HVA homovanillic acid - NM normetanephrine - DA dopamine - DMI desipramine - MAO monoamine oxidase     

Chronic treatment with desipramine caused a sustained decrease of 3,4-dihydroxyphenylglycol-sulphate and total 3-methoxy-4-hydroxyphenylglycol in the rat brain

Summary The 2 major metabolites of norepinephrine (NE), 3,4-dihydroxyphenylglycol-sulphate (DOPEG-SO₄) and free plus conjugated 3-methoxy-4-hydroxyphenylglycol (total-MOPEG), both their endogenous concentrations and their accumulation from the NE-precursors ³H-tyrosine or ³H-dopamine, were determined in the whole rat brain to assess the effect of chronic treatment with desipramine (DMI), imipramine and amitriptyline. DOPEG-SO₄ was decreased 2 h and 24 h after the last administration of DMI (10 mg/kg twice daily for 4, 10 or 20 days) or imipramine (10 mg/kg twice daily for 10 days). When measured within 24 h after the last dose of DMI or imipramine, several schedules resulted in reduced accumulation of total-³H-MOPEG and ³H-NE, while ³H-NE and MOPEG were unchanged in the remaining schedules. These results indicate that DMI retains its ability to decrease NE-turnover over a period of 20 days of treatment. Forty-eight hours or 72 h after the last administration of desipramine and imipramine an overshoot was observed in NE-metabolism, consisting of increased levels of total-³H-MOPEG and endogenous total-MOPEG; DOPEG-SO₄ was some-times concomitantly increased. The overshoot was more consistent after 20 or 10 days of treatment than after 4 days of treatment. This finding, together with a tendency to partial tolerance to the metabolite decreasing effects of DMI, indicate that adaptive changes occur in the NE system after treatment for 10–20 days with DMI or imipramine.Abbreviations Used NE norepinephrine - DOPEG 3,4-dihydroxyphenylglycol - DOPEG-SO₄ DOPEG sulphate ester - MOPEG 3-methoxy-4-hydroxyphenylglycol - total-MOPEG free plus conjugated MOPEG - DOPAC 3,4-dihydroxyphenylacetic acid - HVA homovanillic acid - NM normetanephrine - DA dopamine - DMI desipramine