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PubMed1995

Reoperation on prosthetic heart values. Patient-specific estimates of in-hospital events.

Reoperation on prosthetic heart valves is increasingly under consideration for both clinical and prophylactic indications. To determine the correlates of hospital events, including in-hospital mortality, new persisting neurologic deficit, and length of postoperative stay, a three-institution study of 2246 consecutive prosthetic valve reoperations performed on 1984 patients between 1963 and 1992 was undertaken. The combined experience ranged from high-risk patients coming moribund to the operating room to an important number of well individuals undergoing prophylactic reoperations on potentially failing valves. The risk-unadjusted hospital mortality was 10.8%, neurologic deficit at hospital discharge 1.1%, and length of stay 10 days (median). Multivariably determined correlates of outcome included age at reoperation, degree, severity, and acuity of impairment of cardiac function, extensiveness of valvular heart disease, coexisting morbid conditions, number of previous heart operations, and concomitant procedures. The risk-adjusted hospital mortality for the first elective reoperation in a good-risk patient was 1.3% (90% confidence limits 0.3% to 4.4%), neurologic deficit 0.3% (90% confidence limits 0.02% to 1.8%), and length of postoperative stay 7 days (90% confidence limits 4 to 13), emphasizing the wide variance in outcome events. Equations were developed to permit wide application of the results of the study for quantitatively estimating the risk of outcome events based on individual preoperative patient characteristics. These estimates should be useful for informed patient consent, considerations of prophylactic valve replacement, and cost and resource use.

Adolescent↗
PubMed2003

Survival of previously measles-vaccinated and measles-unvaccinated children in an emergency situation: an unplanned study.

BACKGROUND: Previous studies have suggested that standard measles vaccine may reduce mortality by more than the number of deaths thought to be caused by measles infection in areas with high mortality. However, these observations have not been based on randomized trials. METHODS: During the recent war in Guinea-Bissau, most children fled from the city of Bissau and immunization services in the country broke down for several months. We were performing a trial in which children were randomized at 6 months of age to receive either measles vaccine or inactivated polio vaccine. Because of the war many children did not receive the dose of measles vaccine planned for 9 months of age. We were able to monitor mortality during the war and after. RESULTS: Included in the study were 433 children 6 to 11 months of age. Fifteen children died (3.6%) during the first 3 months of the war before vaccination programs were resumed, 4 of 214 measles-vaccinated children and 11 of 219 children who had received inactivated polio vaccine. The effect of measles vaccine was marked for girls [mortality rate ratio (MR), 0.00; 95% confidence limits, 0.0 to 0.37], whereas there was no difference for boys (MR = 1.02; 95% confidence limits, 0.25 to 3.88). In a combined analysis controlling for factors that differed between the two groups, the MR for measles-vaccinated children was 0.30 (95% confidence limits, 0.08 to 0.87). Prolonging the period of observation to the end of 1998 or including the prewar period did not modify the significant beneficial effect of measles vaccine for girls. Twenty-two of the children in the cohort were reported to have had measles, 8 cases occurring during the 3 months of the war. Exclusion of measles cases in the analysis did not change the results; children who had received measles vaccine had a MR of 0.28 (95% confidence limits, 0.06 to 0.89) during the first 3 months of the war. CONCLUSIONS: Consistent with previous observational studies, measles vaccination was associated with a reduction in mortality that cannot be explained by the prevention of measles infection. This nonspecific beneficial effect was particularly strong for girls. Further studies are needed to examine the extent of nonspecific effects in settings with high mortality.

Cause of Death↗
PubMed1986

Case-control study of multiple myeloma and farming.

A previous case-control study which utilised the occupational information available on the New Zealand Cancer Registry found an increased risk of multiple myeloma in agricultural workers consistent with previous findings in the United States. The findings are now presented for the second phase of the study which involved interviewing 76 cases of multiple myeloma (who had been included in the previous study) together with 315 controls with other types of cancer. The previous finding on an excess of farmers in the case group was confirmed by the interview data (odds ratio = 1.7, 95% confidence limits 1.0-2.9, P = 0.04). There were no significant differences between cases and controls regarding potential exposure to phenoxy herbicides or chlorophenols. There were also no significant differences regarding activities involving potential exposure to other agricultural chemicals, although the odds ratio for fencing work, which may involve exposure to arsenic and sodium pentachlorophenate, was 1.6 (95% confidence limits 0.9-2.7, P = 0.11). The odds ratios were significantly elevated for sheep farming (odds ratio = 1.9, 95% confidence limits 1.0-3.6, P = 0.04) and exposure to beef cattle (odds ratio = 1.7, 95% confidence limits 1.0-2.9, P = 0.05). The odds ratio was also elevated for persons reporting a history of hay fever (odds ratio = 1.9, 95% confidence limits 1.0-3.5, P = 0.05). Overall, these findings suggest that the search for the causes of elevated mortality in farmers from multiple myeloma should be directed to potential causes other than pesticide exposure.

Aged↗
PubMed1990

Cholelithiasis in inflammatory bowel disease. A case-control study.

Cholelithiasis is considered an extraintestinal manifestation of Crohn's ileitis but has not been associated with ulcerative colitis. To evaluate if an increased risk of cholelithiasis exists in patients with ulcerative colitis, biliary ultrasonography was performed on 159 patients with inflammatory bowel disease, 114 patients with ulcerative colitis, and 45 patients with Crohn's disease. A control population of 2453 residents of the town near the authors' institute was also studied. An echographic survey of gallstones was performed on the control subjects, who participated in the Multicentrica Italiana Colelitiasi (MICOL). Seventeen patients with inflammatory bowel disease had gallstones (10.7 percent), 11 patients with ulcerative colitis had gallstones (9.6 percent), and 6 patients with Crohn's disease had gallstones (13.3 percent). In the control population, diagnosis of cholelithiasis was made in 239 subjects (9.7 percent). An estimate of the relative risk (odds ratio) of gallstones in ulcerative colitis and Crohn's disease and also in 4 subgroups formed on the basis of the extent of disease (total ulcerative colitis, partial ulcerative colitis, Crohn's disease with ileitis, Crohn's disease without ileitis) with respect to the general population was calculated using logistic regression with gallstones, sex, age, and body mass index as independent variables and inflammatory bowel disease as a dependent variable. The author's findings show an increased risk of gallstones in both patients with Crohn's disease (odds ratio = 3.6; 95 percent confidence limits = 1.2 - 10.4; P = 0.02) and patients with ulcerative colitis (odds ratio = 2.5; 95 percent confidence limits = 1.2 - 5.2; P = 0.01). The risk was highest in patients with Crohn's disease involving the distal ileum (odds ratio = 4.5; 95 percent confidence limits = 1.5 - 14.1; P = 0.009) and in patients with total ulcerative colitis extending to the cecum (odds ratio = 3.3; 95 percent confidence limits = 1.3 - 8.6; P = 0.01). These results confirm that there is an increased risk of gallstones in Crohn's ileitis but they show that there also exists an increased risk in patients with total ulcerative colitis.

Adult↗
PubMed1990

Cardiovascular death among women under 40 years of age using low-estrogen oral contraceptives and intrauterine devices in Finland from 1975 to 1984.

From 1975 to 1984, there were 1,585,000 women-years of oral contraceptive use and 1,975,000 women-years of copper-bearing intrauterine device use in Finland. During this 10-year period, 20 women between 15 and 39 years of age died of pulmonary embolism, 41 of coronary heart disease, and 311 of intracranial hemorrhage. The diagnoses were confirmed in 89% at necropsy examination. The contraceptive method used by patients was determined in 84% by means of inquiry sent to family planning clinics. Among the 20 patients who died of pulmonary embolism, four died while taking the pill, which gives a relative risk of 1.2 (95% confidence limits, 0.37 to 3.62; p = 0.78). The corresponding values for death from myocardial infarction and intracranial hemorrhage were 0.19 (95% confidence limits, 0.05 to 0.70; p = 0.01) and 0.36 (95% confidence limits, 0.18 to 0.70; p = 0.03), respectively. None among the copper intrauterine device users under the age of 40 years died of pulmonary embolism during 1,383,000 women-years of intrauterine device use. The relative risk of death from intracranial hemorrhage among intrauterine device users was 1.18 (95% confidence limits, 0.70 to 1.99, p = 0.25).

Adolescent↗
PubMed1997

Prevalence of antibodies to HTLV in antenatal clinic attenders in south east London.

The prevalence of antibodies to HTLV in women attending a south east London antenatal clinic between October 1990 and July 1992 was determined using sera referred for routine rubella antibody testing. Samples were screened for HTLV antibody using a modified Fujirebio gel particle agglutination test and reactive sera confirmed by ELISA (Abbott Laboratories, North Chicago, IL) and two commercial Western blots (Cambridge Biotech Inc., Rockville, MD, and Diagnostic Biotechnology, Genelab Diagnostics, Louvaine, Belgium). This strategy confirmed the presence of HTLV-1 antibodies in 12 out of 6,289 sera (0.19%, 95% confidence limits 0.083% to 0.30%) and HTLV-2 antibodies in 2 (0.03%) sera. Specimens from 8 of 821 (0.97%, 95% confidence limits 0.42% to 1.9%) Afro-Caribbean women, three of 1,136 (0.26%, 95% confidence limits 0.055% to 0.78%) African women, and one of 3,049 (0.033%, 95% confidence limits 0.006% to 0.18%) Caucasian women were positive for HTLV-1 antibodies. Sera from Afro-Caribbean women born in the Caribbean were 7.6 times more likely to be HTLV-1 antibody positive than sera from Afro-Caribbean women born in the UK (P = 0.012). Selective testing of Afro-Caribbean and African antenatal clinic attenders, in this setting, would have identified 11 of the 12 HTLV-1 infections at an estimated cost of prevention of HTLV-1 associated disease of 100,000 pounds per case which is considerably less than the 1.3 million pounds which has been estimated to prevent a case by universal screening of UK blood donors.

Ambulatory Care Facilities↗
PubMed1996

Can asphyxiated infants at risk for neonatal seizures be rapidly identified by current high-risk markers?

OBJECTIVE: Markers currently used to identify infants at highest risk for perinatal hypoxic-ischemic cerebral injury are insensitive in predicting the subsequent occurrence of neonatal seizures and/or neurodevelopmental sequelae, ie, cerebral palsy. To facilitate therapeutic strategies, early identification of the infant at highest risk for developing seizures secondary to hypoxia ischemia or asphyxia is critical, particularly if novel but potentially toxic therapies currently under experimental investigation become available for clinical use. METHODS: Ninety-six inborn term infants considered at high risk for having neonatal seizures secondary to hypoxia ischemia or asphyxia and admitted to the neonatal intensive care unit directly after labor and delivery were prospectively evaluated. Markers of high risk included the presence of moderate to thick meconium-stained amniotic fluid (MSAF), fetal heart rate (FHRT) abnormalities abruptio placentae, intubation and positive pressure ventilation in the delivery room (DR), chest compressions and epinephrine administration as part of resuscitation, a 5-minute Apgar score of 5 or less, umbilical cord arterial pH of 7.00 or less, and/or a base deficit of -14 mEq/L or more negative. RESULTS: Seizures developed in 5 (5.2%) of the 96 infants. High-risk markers included FHRT abnormalities only (n=36), FHRT abnormalities and MSAF (n=20), MSAF only (n=23), abruptio placentae (n=6), intubation in the DR (n=44), intubation in the neonatal intensive care unit (n=22), chest compressions (n=2), 5-minute Apgar scores of 5 or less (n=21), umbilical cord arterial pH of 7.00 or less (n=21), and base deficits of -14 mEq/L or more negative (n=19). By univariate analysis, significant relationships with seizures were found with Apgar scores, the need for intubation in the DR, umbilical cord arterial pH, and base deficit. Combinations of the identified risk markers showed a strong relationship with seizures with the following odds rations (ORs), 95% confidence limits, sensitivity, specificity, and positive predictive values (PPVs): (1) low cord pH and intubation, OR, 163 (confidence limits, 7.9 and 3343.7); sensitivity, 100%; specificity 94%; and PPV, 50%; (2) low cord pH and low 5-minute Apgar score, OR, 39 (confidence limits, 3.9 and 392.5); sensitivity, 80%; specificity, 91%; and PPV, 33.3%; and (3) low pH, intubation, and low 5-minute Apgar score, OR, 340 (confidence limits, 17.8 and 6480.6); sensitivity, 80%; specificity, 98.8%; and PPV, 80%. CONCLUSIONS: A combination of high-risk postnatal markers, specifically, a low 5-minute Apgar score and intubation in the DR in association with severe fetal acidemia, facilitates the identification within the first hour of life of term infants at highest risk for developing seizures secondary to perinatal asphyxia.

Abruptio Placentae↗
PubMed1983

[Estimation of platelet-bound IgG by means of a test using radioactive antiglobulin].

A method of evaluation of platelet bound IgG (PA IgG) is described. This method rely upon the fixation of a radio-labelled goat anti-human IgG on platelets. Each new batch of labelling of the antiglobulin is tested with a reference system using a semi-purified anti-D IgG and O R1R1 and O rr erythrocytes. This system is used for the standardization and the validation of the antiglobulin, and it allows to make correspond an amount of antiglobulin to a known quantity of IgG molecules. The normal level of PA IgG in 98 healthy controls was found to be 351 +/- 252 antiglobulin combining sites (ACS) per platelet. The upper limit (99% confident limit) in the controls is 999 ACS per platelet. 412 thrombocytopenic patients have been tested, 78.7% of ITP had an elevated PA IgG. However positive results are also frequent in other thrombocytopenia even when an immune mechanism cannot be evoked. These positive results raise the problem of the signification of PA IgG and of their exact nature. Further dates are necessary to ascertain the role of auto-antibodies, immune complexes or of platelet membrane modifications in PA IgG increase.

Adult↗
PubMed2000

Assessment of intracellular water by whole body bioelectrical impedance and total body potassium in HIV-positive patients.

OBJECTIVE: Bioelectrical impedance analysis (BIA) is widely used as bedside assessment of body composition. Body cell mass (BCM) and intracellular water (ICW) are clinically important body compartments. Estimates of ICW obtained from BIA by different calculation approaches were compared to a reference method in male HIV-infected patients. PATIENTS: Representative subsample of clinically stable HIV-infected outpatients, consisting of 42 men with a body mass index of 22.4 +/- 3.8 kg/m(2)(range, 13-l31 kg/m(2)). METHODS: Total body potassium was assessed in a whole body counter, and compared to 50 kHz monofrequency BIA and multifrequency bioelectrical impedance spectroscopy. Six different prediction equations for ICW from BIA data were applied. Methods were compared by the Bland-Altman method. RESULTS: BIA-derived ICW estimates explained 58% to 73% of the observed variance in ICW (TBK), but limits of confidence were wide (-16.6 to +18.2% for the best method). BIA overestimated low ICW (TBK) and underestimated high ICW (TBK) when normalized for weight or height. Mono- and multifrequency BIA were not different in precision but population-specific equations tended to narrower confidence limits. CONCLUSION: BIA is an unreliable method to estimate ICW in this population, in contrast to the better established estimation of total body water and extracellular water. Potassium depletion in severe malnutrition may contribute to this finding but a major part of the residual between methods remains unexplained.

Acquired Immunodeficiency Syndrome↗
PubMed2006

Comparative bioavailability of two oral suspensions of naproxen sodium.

The bioavailability of naproxen sodium (CAS 26159-34-2) after administration of two oral suspensions, reference or test (Pactens), was compared in 24 healthy subjects. The volunteers received an oral dose of 250 mg (10 ml) in two separate sessions under fasting conditions according to a randomized cross-over design and blood samples were obtained at selected times for a period of 72 h. Plasma samples were analyzed by a high-performance liquid chromatographic method for determination of naproxen. Individual plasma concentration against time curves were constructed and pharmacokinetic parameters were obtained by non-compartmental techniques. The parameters obtained (mean +/- S.E.M.) were: C(max) 43.93 +/- 1.83 and 44.91 +/- 2.15 microg/ml, t(max) 2.38 +/- 0.21 and 1.83 < or = 0.19 h, AUC(72 h) 721.73 +/- 18.47 and 722.55 +/- 19.07 microg x h/ml for reference and test formulations, respectively. Maximal concentration, AUC(72 h) and AUC(infinity). were log transformed and compared by analysis of variance and ratios; in addition, 90% confidence limits were obtained. As confidence limits were included in the 80-125% range and the probability of exceeding these intervals was always lower than 0.05, it is concluded that the formulations tested are bioequivalent.

Adult↗
PubMed1991

Serum platelet-derived growth factor and endothelin concentrations in human hypercholesterolaemia.

Platelet-derived growth factor (PDGF) and endothelin are both smooth muscle cell mitogens, and may have an important role in mediation of the proliferative phase of atherogenesis. Since hypercholesterolaemia is an important risk factor for atherosclerosis, we have measured serum endothelin and PDGF concentrations in matched pairs of hypercholesterolaemic patients and control subjects. Both endothelin and PDGF concentrations were higher in the hypercholesterolaemic patients (23.8 +/- 4.3 pM vs. 21.7 +/- 2.4 pM, P = 0.019, median difference 3.0, 95% confidence limits 0.6-7.3, and 115.4 +/- 60.3 pM vs. 64.7 +/- 22.7 pM P = 0.033, median difference 27.2, 95% confidence limits 1.3-82.5, respectively), while serum endothelin and PDGF concentrations were positively correlated with each other (r = 0.764, P less than 0.0001, 95% confidence limits 0.505-0.897). PDGF concentrations were correlated with the peripheral blood platelet count (r = 0.560, P = 0.007, 95% confidence limits 0.180-0.794). These findings suggest that PDGF, and possibly endothelin, may be involved in hypercholesterolaemia-related atherogenesis.

Adult↗
PubMed2001

Preventing drug interactions by online prescription screening in community pharmacies and medical practices.

BACKGROUND: Drug interactions have been shown to be preventable by computerized prescription entry and screening only in hospitals and not in community-based practice. METHODS: We retrospectively evaluated the effect of online prescription screening in community pharmacies and physician offices of one health maintenance organization, phased in during 3 consecutive 6-month periods in 1998 to 1999 (period I, system active only in 40% of pharmacies; period II, system active in 90% of pharmacies and 50% of physician offices; period III, system active in 95% of pharmacies and 90% of physician practices), on rates of prescriptions with-, patient exposure to-, and physician prescribing of-potential drug interactions. FINDINGS: Cumulative data included 775,186 patients given at least one prescription, by one or more of 5504 physicians, whose prescriptions were dispensed at 572 pharmacies. Dispensing of drug interaction prescriptions was reduced by 21.1% and by 67.5% in periods II and III compared with period I (odds ratio, 0.79; 95% confidence limit, 0.75-0.83 and odds ratio, 0.28; 95% confidence limit, 0.26-0.30, respectively). Patient exposure decreased only in those receiving 3 to 7 concurrent drugs (odds ratio, 0.80; 95% confidence limit, 0.71-0.90) with no reductions for patients who were given 2 drugs or 8 or more drugs. Only 19% to 25% of physicians wrote prescriptions for drugs that interact, but 85% of these repeated this pattern after being alerted. The proportion of prescriptions of drugs that interact that originated with a single prescriber, as opposed to 2 prescribers, decreased during the 3 periods from 0.81 to 0.74 and 0.69 (P <.001). INTERPRETATION: Computerized prescription entry and drug interaction screening in the community caused a 62.8% reduction in pharmacy-dispensed prescriptions with severe drug interactions and a 20% reduction in patient exposure to prescriptions with severe drug interactions; this reduction was negated by polypharmacy of 8 or more drugs. The effect of interaction alerts on physician prescribing patterns was limited.

Adult↗
PubMed1991

Results of the Fontan procedure for patients with univentricular heart.

One hundred twenty-four consecutive patients with univentricular heart undergoing the Fontan operation were reviewed. Patients with tricuspid atresia or biventricular heart with hypoplasia of one ventricle were excluded. Eighty-four patients had left ventricular morphology. Atrioventricular connection was double-inlet (n = 76), common (n = 29), absent left atrioventricular connection (n = 14), and absent right atrioventricular connection (n = 5). Actuarial survival was 77% (70% confidence limits, 73% to 81%) at 1 year, 66% (70% confidence limits, 60% to 72%) at 5 years, and 49% (70% confidence limits, 36% to 61%) at 10 years, indicating a continuing risk for premature death. Multivariate analysis identified preoperative ventricular function and hypertrophy as risk factors for survival. High postrepair right atrial pressure (greater than 15 mm Hg) emerged as a strong intraoperative predictor of survival. Logistic regression analysis of these factors predicts high probability of death for certain subgroups of patients after the Fontan operation. Forty-four percent (n = 53) of these original 124 patients are alive and in New York Heart Association class I at follow-up. Thirty-eight percent (n = 33) of survivors have worse ventricular function than preoperative. Long-term survival is disappointing. Certain identifiable subgroups of patients with univentricular heart have unacceptable risks for the Fontan operation and should have alternate management. High postrepair right atrial pressure is an ominous sign, and if it persists the Fontan should be fenestrated or taken down.

Adolescent↗
PubMed1990

Differences in the quality of semen in outdoor workers during summer and winter.

BACKGROUND AND METHODS: In warm climates throughout the world, there is a deficit of births during the spring season. To determine whether this deficit might reflect a deleterious effect of heat on the male reproductive capacity during the previous summer, we obtained semen specimens in summer and winter from normal men who worked outdoors in the vicinity of San Antonio, Texas, and we performed automated semen analyses with an image-analysis system. RESULTS: Pairwise comparisons among 131 men without azoospermia who contributed specimens in both summer and winter revealed significant reductions during the summer in sperm concentration, total sperm count per ejaculate, and concentration of motile sperm. The mean decreases in these values after adjustment for potential confounding characteristics were 32 percent (95 percent confidence limits, 28 and 44 percent), 24 percent (95 percent confidence limits, 18 and 43 percent), and 28 percent (95 percent confidence limits, 24 and 44 percent), respectively (P less than 0.0001). The lower a subject's average sperm concentration and motile-sperm concentration, the greater the reduction. We found no correlation, however, between the number of hours per day spent working during summer in settings without air conditioning and either the summer sperm concentration or the difference in concentration between summer and winter. Among the children of the men in the study whose wives were living near San Antonio during the year before they gave birth, a disproportionately low number were born during the spring. CONCLUSIONS: Semen quality deteriorates during the summer. This phenomenon may account at least in part for the reduction in the birth rate during the spring in regions with warm climates.

Adult↗
PubMed1989

Clonidine-induced hypoactivity and mydriasis in mice are respectively mediated via pre- and postsynaptic alpha 2-adrenoceptors in the brain.

Since brain alpha 2-adrenoceptors occur both pre- and postsynaptically, experiments were carried out to determine the synaptic locations of those receptors mediating clonidine-induced hypoactivity and mydriasis. Intraperitoneal (i.p.) injection of clonidine (1-3000 micrograms/kg) to mice dose dependently induced these two responses and also decreased brain concentrations of 3-methoxy-4-hydroxyphenylglycol (MHPG). The ED50 values were: 120 micrograms/kg for hypoactivity (95% confidence limits 103-140 micrograms/kg), 54 micrograms/kg for mydriasis (95% confidence limits 40-74 micrograms/kg) and 18 micrograms/kg for MHPG reduction (95% confidence limits 8-36 micrograms/kg) suggesting that these responses could all be presynaptically mediated. However, methamphetamine which increases noradrenaline turnover was found to dose dependently produce mydriasis, but not hypoactivity, after peripheral (0.1-5 mg/kg i.p.) or central (0.5-10 micrograms i.c.v.) injection. The mydriasis produced by methamphetamine (0.5 mg/kg i.p.) was abolished by i.c.v. injection of 1 micrograms idazoxan or yohimbine, but not 2.5 micrograms prazosin or pindolol, showing this effect was mediated by central alpha 2-adrenoceptors. Methamphetamine (1-10 micrograms i.c.v.) potentiated the mydriasis induced by clonidine (50 micrograms/kg i.p.) suggesting this was a postsynaptic alpha 2-adrenoceptor response. By contrast, methamphetamine (1-10 micrograms i.c.v.) dose dependently reversed clonidine (100 micrograms/kg i.p.) hypoactivity indicating this response was mediated by presynaptic alpha 2-adrenoceptors. These hypotheses were confirmed by destruction of noradrenergic neurones using DSP-4 (100 mg/kg i.p. x 2). This treatment prevented the mydriasis response to methamphetamine (0.5 mg/kg i.p.), but not clonidine (100 micrograms/kg i.p.) and markedly attenuated clonidine (100 micrograms/kg i.p.) hypoactivity.

Animals↗
PubMed1985

A mysterious cluster of deaths and cardiopulmonary arrests in a pediatric intensive care unit.

In the period April 1981 through June 1982, there was an unusual increase in the number of deaths and cardiopulmonary arrests in the pediatric intensive care unit at a large medical center hospital in San Antonio, Texas. During this period, 34 of 42 deaths (81 per cent) occurred in the evening work shift, as compared with 36 of 106 (34 per cent) during the previous four years (P less than 0.0001). Reviews of records of patients revealed no association between death in this 15-month epidemic period and a variety of demographic, historical, medical, and admission characteristics; medical or surgical procedures; or the severity of illness. The findings of a blinded clinical consultant support the conclusion that the increase in deaths and cardiopulmonary arrests could not be explained on the basis of the clinical status of the patients, and the consultant concluded that during the epidemic period, there were more deaths and cardiopulmonary arrests that were either unexpected in timing or inconsistent with the previous clinical course. The presence of one nurse was associated with the increased numbers of deaths (relative risk, 10.7; 95 per cent confidence limits, 6.4 to 17.9), cardiopulmonary arrests (relative risk = 25.5, confidence limits = 16.8 to 38.6), and unexpected clinical events, (relative risk, infinite; confidence limits, 33.7 to infinity). Although the cause of the epidemic remains unclear, the findings illustrate that surveillance of deaths and cardiopulmonary resuscitation may allow early recognition of similar problems in other hospitals.

Child↗
PubMed1976

Study of a proposed international standard for blood coagulation factor IX.

An International Collaborative Study was organized to establish a standard for factor IX. Two freeze-dried concentrate preparations, C1 and C2, and one freeze-dried plasma P were compared with each other, with fresh normal plasmas and with local standards in 13 laboratories. One of the concentrate preparations (C1) contained heparin and this gave rise to non-parallel assays in laboratories testing concentrate C1 in dilutions containing more than 0.05 i.u. of heparin per ml. Assays of factor IX showed good precision for both plasma and concentrate in all laboratories; no systematic effect of method, operator or day of assay was detected. The plasma preparation P and the concentrate preparation C2 were compared with 59 individual fresh normal plasma samples, and a mean potency ratio of 0.78 (95% confidence limits 0.73-0.84) for plasma and 5.62(95% confidence limits 5.13-6.16) for the concentrate C2 obtained. Only 21 estimates of concentrate C1 in terms of fresh plasma were obtained giving a mean potency ratio of 3.85 (95% confidence limits 1.87-7.92). The estimated loss of potency for freeze-dried plasma stored at -20 degrees C is approximately 0.4% per year. The concentrate C2 is apparently more stable and only very small losses occurred even at higher storage temperatures. All participants agreed that the preparation C2 would be suitable to serve as an International Standard for factor IX; they also agreed that the figure assigned for the unitage should be based on the number of ml of 'average fresh normal plasma' estimated to contain the factor IX activity of one ampoule of the preparation. It is proposed to recommend to the World Health Organization that the preparation of factor IX concentrate C2, in ampoules coded 72/32, be considered for establishment as the International Standard for factor IX, and that the international unit for factor IX be assigned on the basis of 5.62 units per ampoule of this preparation.

Blood Preservation↗
PubMed1991

BAY P 1455, a thiazolylaminobenzimidazole derivative with gastroprotective properties in the rat.

The antiulcer activity of BAY P 14551 a thiazolylaminobenzimidazole derivative, was evaluated in different experimental ulcer models and its antiulcer activity was compared to that of different reference drugs. The overall activity of the compound was equal to or more potent than that of reference antiulcer drugs, such as pirenzepine, cimetidine and carbenoxolone, but it was not as potent as rioprostil. The ED50 values (expressed as mumol/kg p.o.) were 68 (confidence limits: 51-91) for indomethacin-induced ulcers, 21 (confidence limits: 13-31) for stress-induced ulcers and 1260 mumol/kg p.o. (confidence limits: 412-3800) for ulcers induced by absolute ethanol. The compound had no activity against cysteamine-induced duodenal ulcers and lost its cytoprotective activity in adrenalectomised rats. Since inhibition of gastric acid secretion was seen, if at all, only with the higher doses, the gastro-protective action of BAY P 1455 seemed not to be due to an antisecretory effect, but more likely to a gastroprotective action as hypothesised for prostaglandins.

Adrenalectomy↗