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PubMed1989

Oral contraception, smoking and inflammatory bowel disease--findings in the Royal College of General Practitioners Oral Contraception Study.

Data from the Royal College of General Practitioners Oral Contraception Study have been examined to determine whether oral contraceptive use was associated with the development of Crohn's disease or ulcerative colitis. Over a 17 year period Crohn's disease developed in 42 women and ulcerative colitis in 78. The incidence of both diseases was greater in oral contraceptive users compared to non-users with the rate ratio for Crohn's disease being 1.7 (95% confidence limits, 0.88, 3.2) and for ulcerative colitis being 1.3 (95% confidence limits 0.82, 2.0). For both diseases incidence was unrelated to parity or social class, but women smoking at recruitment had a greater incidence of Crohn's disease (rate ratio 1.8, 95% confidence limits 0.93, 3.3) and a reduced incidence of ulcerative colitis (rate ratio 0.68, 95% confidence limits 0.41, 1.1). Although these results are based on small numbers and could be chance findings, they are consistent with other studies showing associations between oral contraceptive use, smoking and the development of Crohn's disease and ulcerative colitis.

Adolescent↗
PubMed2003

Combined estimates of effectiveness of mifepristone 10 mg in emergency contraception.

The present paper combines the estimates of efficacy and side effects of 10 mg mifepristone for emergency contraception obtained from randomized trials. A total of 6083 women participating in 12 randomized trials and receiving 10 mg mifepristone for emergency contraception up to 120 h after intercourse, were analyzed for efficacy. Between 4188 and 5833 women were analyzed for side effects and 3601 for delay of menses of more than 7 days. Prevented fractions, the effect of delay and of further acts of intercourse after treatment administration were analyzed in 3440 women, using individual data. The combined pregnancy rate from all the 12 trials was 1.7% [101/6083, 95% confidence interval (CI): 1.3-2.2]. From the three trials providing individual data, the combined pregnancy rate was 1.3% (45/3440, 95% CI: 0.9-1.7) and the estimate of pregnancies prevented was 83.4% (95% CI: 77.4-87.8). There was a sharp decline in efficacy when treatment was administered during the 5th day after intercourse compared to administration during the 1st day, the odds of pregnancy increasing by a factor of 5.3 (95% CI: 1.9-14.9). The relative risk of pregnancy was about 28 times higher among women with unprotected acts of coitus between treatment administration and the onset of next menses, compared with women reporting none [odds ratio (OR) = 27.6, 95% CI: 12.7-60.2]. The increase in risk for women reporting protected acts of intercourse during this interval was not statistically significant (OR = 1.8, 95% CI: 0.9-3.8). There was a large heterogeneity among trials in all side effects and delay of menses of more than 7 days (all had p < 0.0001 for the test of homogeneity). The percentage of women with nausea ranged from 0.0-19.4% (highest upper 95% confidence limit: 23.0%), that of vomiting from 0.0-4.3% (highest upper 95% confidence limit: 6.1%), that of lower abdominal pain from 4.3-19.1% (highest upper 95% confidence limit: 22.7%). The percentage of women with delay of menses of more than 7 days ranged from 4.3-25.8% (highest upper 95% confidence limit: 34.1%). We conclude that 10 mg mifepristone is an effective emergency contraception regimen, with an acceptable side-effects profile. Postponing treatment until the 5th day seriously decreases efficacy. The risk of pregnancy is dramatically increased among women having unprotected acts of intercourse between treatment administration and the onset of next menses. This risk may be enhanced for women whose ovulation is postponed by treatment.

Adult↗
PubMed1997

Multiple-time-point dissolution specifications for a sampling acceptance plan.

In dissolution testing, multiple dissolution measurements at specific time points are used to obtain the dissolution characteristics for most extended-release and some immediate-release drug products. This paper presents a general procedure for defining specifications by a multivariate confidence region or by simultaneous confidence limits on the dissolution values of individual time points. The confidence regions and simultaneous confidence limits were estimated using two approaches: the first approach assumed a multivariate normal distribution on the multiple dissolution values and the second approach used the bootstrap resampling method. The multivariate confidence region was constructed using the Hotelling's T2 statistic (equivalently, Mahalanobis distance D2), and the simultaneous confidence limits were based on the Mahalanobis statistic as well as on the Bonterroni adjustment. The Mahalanobis simultaneous confidence limits specification criteria have the overall false out-of-specification rate too low in both parametric and bootstrap approaches.

Chemistry, Pharmaceutical↗
PubMed1992

Optimum treatment of discrete subaortic stenosis.

Discrete subaortic stenosis typically appears as a well-defined membrane beneath the aortic valve. To assess the merits of alternative approaches to this problem, we have reviewed the results of operations for discrete subaortic stenosis from 1978 through 1990. Excision of the subaortic membrane alone was performed in 16 patients (group I). Excision of the membrane with resection of septal muscle was performed in 24 patients (group II). The groups were similar in age at operation, duration of follow-up, and preoperative and postoperative transvalvar gradients. There were no operative or late deaths. Reoperations for recurrent subaortic stenosis were performed in 4 group I patients (25%; 70% confidence limits, 16% to 38%) and 1 group II patient (4%; 70% confidence limits, 2% to 11%). Pacemakers were inserted for postoperative complete heart block in 1 group I patient (6%; 70% confidence limits, 2% to 16%) and 2 group II patients (8%; 70% confidence limits, 4% to 16%). We conclude that muscle resection combined with membrane excision in patients with discrete subaortic stenosis does not increase the risk of death or heart block, and does lower the risk of reoperation for recurrent subaortic stenosis.

Actuarial Analysis↗
PubMed1997

Differential involvement of serotonin 2A/C and thromboxane A2/prostanoid receptors in high- vs. low-shear rate arterial thrombosis in rabbits.

Experiments performed in 226 pentobarbitone-anesthetized rabbits were designed to investigate the involvement of thromboxane/prostanoid and 5-hydroxytryptamine (5-HT)2A/C receptors during arterial thrombus formation in distinct low- and high-shear rate thrombosis models. Antithrombotic activities of the thromboxane/prostanoid receptor antagonist SQ 29,548 and two chemically distinct 5-HT2A/C receptor antagonists, ritanserin and ketanserin, were assessed first in low-shear rate (approximately 600 sec(-1)) arterial thrombosis, produced by insertion of a silk thread as thrombogenic substrate into the central section of an extracorporeal arteriovenous shunt established between the left carotid artery and the right jugular vein (n = 77), and second in high-shear rate (approximately 40,000 sec(-1)) arterial thrombosis, produced by critical stenosis and local endothelial injury of a carotid artery, characterized by cyclic flow reductions (CFRs) due to recurrent platelet aggregation and subsequent dislodgement of the thrombus (n = 149). Under low shear rate, SQ 29,548 (10-2500 microg/kg plus 10-2500 microg/kg/hr i.v.), but not ritanserin or ketanserin (both at 2500 microg/kg i.v.), dose-dependently inhibited thrombus formation. In contrast, under high shear rate, SQ 29,548 (10-160 microg/kg plus 10-160 microg/kg/hr i.v.) and both ritanserin and ketanserin (both at 10-2500 microg/kg i.v.) dose-dependently reduced CFR frequency, with ID50 values of 35 microg/kg (95% confidence limits, 24-58 microg/kg), 77 microg/kg (95% confidence limits, 40-132 microg/kg) and 89 microg/kg (95% confidence limits, 36-285 microg/kg) i.v., respectively. Furthermore, local infusion of the stable thromboxane A2 analog U-46619 (0.63 microg/kg/min) or 5-HT (20.8 microg/kg/min) proximal to the site of injury and stenosis in rabbits pretreated with either SQ 29,548 (40 microg/kg plus 40 microg/kg/hr i.v.) or ritanserin (160 microg/kg i.v.), respectively, restored CFR frequency to vehicle group levels in animals whose CFR frequency was previously reduced. The inhibitory activity of ketanserin and ritanserin on CFRs could not be attributed to 5-HT1B/D or alpha-1 adrenoceptor antagonist properties or to any hypotensive activity. These results provide firm evidence that thromboxane/prostanoid receptors are involved in arterial thrombosis in rabbits independently of the shear rate, whereas 5-HT2A/C receptors play a major role only in high-shear rate thrombus formation.

Animals↗
PubMed2004

Progression and variability of competitive performance of Olympic swimmers.

Estimates of progression and variability of athletic performance in competitions are useful for researchers and practitioners interested in factors that affect performance. We used repeated-measures mixed modelling to analyse 676 official race times of 26 US and 25 Australian Olympic swimmers in the 12-month period leading up to the 2000 Olympic Games. Progression was expressed as percent changes in mean performance; variability was expressed as the coefficient of variation in performance of an individual swimmer between races. Within competitions, both nations showed similar improvements in mean time from heats through finals (overall 1.2%; 95% confidence limits 1.1 to 1.3%). Mean competition time also improved over 12 months by a similar amount in both nations (0.9%; 95% confidence limits 0.6 to 1.2%). The US swimmers showed a greater improvement between the finals (a difference of 0.5%; 95% confidence limits -0.2 to 1.1%), which paralleled changes in the medal haul of the two nations. The coefficient of variation in performance time for a swimmer between races was 0.60% (95% confidence limits 0.56 to 0.65%) within a competition and 0.80% (95% confidence limits 0.73 to 0.86%) between competitions. Our results show that: (a) to stay in contention for a medal, an Olympic swimmer should improve his or her performance by approximately 1% within a competition and by approximately 1% within the year leading up to the Olympics; (b) an additional enhancement of approximately 0.4% (one-half the between-competition variability) would substantially increase the swimmer's chances of a medal.

Adolescent↗
PubMed2006

The reliability and validity of a field hockey skill test.

High test retest reliability is essential in tests used for both scientific research and to monitor athletic performance. Thirty-nine (20 male and 19 female) well-trained university field hockey players volunteered to participate in the study. The reliability of the in house designed test was determined by repeating the test (3 - 14 days later) following full familiarisation. The validity was assessed by comparing coaches ranks of players with ranked performance on the skill test. The mean difference and confidence limits in overall skill test performance was 0.0 +/- 1.0 % and the standard error (confidence limits) was 2.1 % (1.7 to 2.8 %). The mean difference and confidence limits for the "decision making" time was 0.0 +/- 1.0 % and the standard error (confidence limits) was 4.5 % (3.6 to 6.2 %). The validity correlation (Pearson) was r = 0.83 and r = 0.73 for female players and r = 0.61 and r = 0.70 for male players for overall time and "decision making" time respectively. We conclude that the field hockey skill test is a reliable measure of skill performance and that it is valid as a predictor of coach-assessed hockey performance, but the validity is greater for female players.

Decision Making↗
PubMed1998

[Effects of doxepin on isolated basilar and saphenous artery rings of rabbits].

AIM: To study the effects of doxepin (Dox) on cerebral artery. METHODS: The effects of Dox were observed using the isolated basilar and saphenous artery rings of rabbits. RESULTS: Dox inhibited the constriction of the basilar and saphenous artery rings evoked by KCl with IC50 5.75 mumol.L-1 (95% confidence limits were 2.3-14 mumol.L-1, n = 8) and 34.6 mumol.L-1 (95% confidence limits were 3.8-316 mumol.L-1, n = 8), respectively. Dox also inhibited the constriction of the basilar and saphenous artery rings of the rabbits stimulated by 5-hydroxytryptamine (5-HT), IC50 were 6.3 mumol.L-1 (95% confidence limits were 1.7-23.3 mumol.L-1, n = 7) and 8.0 mumol.L-1 (95% confidence limits were 6.3-10.3 mumol.L-1, n = 6), respectively. In both samples (basilar and saphenous artery rings) CaCl2 evoked, the pD2 of Dox was 5.28 +/- 0.40 and 4.76 +/- 0.14, respectively (n = 6, P < 0.01). Dox 5.8 mumol.L-1 inhibited the constriction of the saphenous artery evoked by norepinephrine (NE) in Ca(2+)-free medium. Dox 30 mumol.L-1 inhibited the constriction of the saphenous artery evoked both by NE and by readmission of CaCl2 (1.25 mmol.L-1). CONCLUSION: As compared with its effect on the saphenous artery, Dox selectively inhibited the basilar artery.

Animals↗
PubMed2005

Genotoxic activity and inhibition of soil respiration by ptaquiloside, a bracken fern carcinogen.

Ptaquiloside (PTA) is a natural toxin produced by bracken (Pteridium aquilinum [L.] Kuhn). Assessment of PTA toxicity is needed because PTA deposited from bracken to soil may leach to surface and groundwater. Inhibition of soil respiration and genotoxic activity of PTA was determined by a soil microbial carbon transformation test and an umu test, respectively. In the carbon transformation test, sandy loam soil was incubated at five different initial concentrations of PTA for a period of 28 d, after which glucose was added and respiration measured for 12 consecutive hours. The tests were performed at 20 degrees C and soil moisture content of approximately 15%. For soil material sampled in the autumn, initial PTA concentrations ranging from 0.008 to 40.6 microg PTA/g dry soil were tested. From fitting of data by a sigmoidal function, a 10% effect dose (ED10) was estimated to 13 microg PTA/ g dry soil, with an upper 95% confidence limit of 43 microg PTA/g dry soil and a 95% lower confidence limit of -infinity microg PTA/g dry soil. For soil material sampled in late winter, initial PTA concentrations ranging from 1.56 to 212 microg PTA/g dry soil were tested, resulting in an ED10 value of 55 microg PTA/g dry soil, with an upper 95% confidence limit of 70 microg PTA/g dry soil and a 95% lower confidence limit of 40 microg PTA/g dry soil. The genotoxic activity of PTA was determined using the umu test without and with metabolic activation (addition of S9 rat liver homogenate). In tests with addition of S9, the induction ratio exceeded the critical ratio of 1.5 at a PTA concentration of 46 +/- 16 microg/ml and, in tests without S9, the critical ratio was exceeded at a PTA concentration of 279 +/- 22 microg/ml. The genotoxicity of PTA is comparable to that of quercetin, another bracken constituent. The toxicity of PTA toward microorganisms prolongs the persistence of PTA in terrestrial environments, increasing the risk of PTA leaching to drainage and groundwater.

Carbon↗
PubMed2006

Anthropometry profiles of elite rugby players: quantifying changes in lean mass.

OBJECTIVE: To demonstrate the utility of a practical measure of lean mass for monitoring changes in the body composition of athletes. METHODS: Between 1999 and 2003 body mass and sum of seven skinfolds were recorded for 40 forwards and 32 backs from one Super 12 rugby union franchise. Players were assessed on 13 (7) occasions (mean (SD)) over 1.9 (1.3) years. Mixed modelling of log transformed variables provided a lean mass index (LMI) of the form mass/skinfolds(x), for monitoring changes in mass controlled for changes in skinfold thickness. Mean effects of phase of season and time in programme were modelled as percentage changes. Effects were standardised for interpretation of magnitudes. RESULTS: The exponent x was 0.13 for forwards and 0.14 for backs (90% confidence limits +/-0.03). The forwards had a small decrease in skinfolds (5.3%, 90% confidence limits +/-2.2%) between preseason and competition phases, and a small increase (7.8%, 90% confidence limits +/-3.1%) during the club season. A small decrease in LMI (approximately 1.5%) occurred after one year in the programme for forwards and backs, whereas increases in skinfolds for forwards became substantial (4.3%, 90% confidence limits +/-2.2%) after three years. Individual variation in body composition was small within a season (within subject SD: body mass, 1.6%; skinfolds, 6.8%; LMI, 1.1%) and somewhat greater for body mass (2.1%) and LMI (1.7%) between seasons. CONCLUSIONS: Despite a lack of substantial mean changes, there was substantial individual variation in lean mass within and between seasons. An index of lean mass based on body mass and skinfolds is a potentially useful tool for assessing body composition of athletes.

Adult↗
PubMed2004

Conformational changes of troponin C within the thin filaments detected by neutron scattering.

Regulation of skeletal and cardiac muscle contraction is associated with structural changes of the thin filament-based proteins, troponin consisting of three subunits (TnC, TnI, and TnT), tropomyosin, and actin, triggered by Ca2+-binding to TnC. Knowledge of in situ structures of these proteins is indispensable for elucidating the molecular mechanism of this Ca2+-sensitive regulation. Here, the in situ structure of TnC within the thin filaments was investigated with neutron scattering, combined with selective deuteration and the contrast matching technique. Deuterated TnC (dTnC) was first prepared, this dTnC was then reconstituted into the native thin filaments, and finally neutron scattering patterns of these reconstituted thin filaments containing dTnC were measured under the condition where non-deuterated components were rendered "invisible" to neutrons. The obtained scattering curves arising only from dTnC showed distinct difference in the absence and presence of Ca2+. These curves were analyzed by model calculations using the Monte Carlo method, in which inter-dTnC interference was explicitly taken into consideration. The model calculation showed that in situ radius of gyration of TnC was 23 A (99% confidence limits between 22 A and 23 A) and 24 A (99% confidence limits between 23 A and 25 A) in the absence and presence of Ca2+, respectively, indicating that TnC within the thin filaments assumes a conformation consistent with the extended dumbbell structure, which is different from the structures found in the crystals of various Tn complexes. Elongation of TnC by binding of Ca2+ was also suggested. Furthermore, the radial position of TnC within the thin filament was estimated to be 53 A (99% confidence limits between 49 A and 57 A) and 49 A (99% confidence limits between 44 A and 53 A) in the absence and presence of Ca2+, respectively, suggesting that this radial movement of TnC by 4A is associated with large conformational changes of the entire Tn molecule by binding of Ca2+.

Animals↗
PubMed2003

Nutritional risk factors for postoperative complications in Brazilian elderly patients undergoing major elective surgery.

OBJECTIVE: In this prospective study, we assessed nutritional and immunologic risk factors for infectious complications and deaths related to infection in elderly patients undergoing major elective surgery. METHODS: Seventy patients 60 y or older were enrolled in this study. The preoperative variables analyzed were body mass index, body mass index knee height, triceps skinfold, subscapular skinfold, mid-arm muscle circumference, mid-arm muscle area, albumin, transferrin, prealbumin, and retinol-binding protein levels, immunoglobulins G, A, and M, C3, and C4 levels, total lymphocyte counts, and the occurrence of delayed hypersensitivity reactions (multitest). RESULTS: Abnormally low levels of prealbumin (P = 0.004), retinol-binding protein (P = 0.05), and transferrin (P = 0.04) were related to infectious complications. Prealbumin levels (P = 0.02) and lymphocyte counts below 1500 cells/mm(3) (P = 0.04) were associated with mortality secondary to infection. Univariate regression analysis showed that levels of prealbumin (P = 0.02, odds ratio = 13.3, 95% confidence limits = 1.6, 110.9), retinol-binding protein (P = 0.03, odds ratio = 4.8, 95% confidence limits = 1.2, 19.3), and transferrin (P = 0.03; odds ratio = 4.2, 95% confidence limit = 1.2, 15.6) were associated with infectious complications. Multivariate analysis associated only prealbumin levels with infectious complications (P = 0.02, odds ratio = 13.3, 95% confidence limit = 1.6, 110.9). Regression analysis provided no conclusion regarding mortality because of the small number of deaths recorded. CONCLUSIONS: In patients with a good cardiac index (Goldman I and II) who underwent major elective surgery, prealbumin protein, retinol-binding protein, and transferrin levels below normal values represented a significant risk for postoperative infectious complications. Lymphocyte counts lower than 1500/m(3) and abnormal prealbumin values were associated with postoperative mortality secondary to infection. The anthropometric variables evaluated did not predict postoperative infectious complications and mortality.

Aged↗
PubMed1993

The delay before onset of accelerated tumour cell repopulation during radiotherapy: a direct maximum-likelihood analysis of a collection of worldwide tumour-control data.

The worldwide collection of control data for head and neck tumours presented by Withers et al. (Withers, H.R., Taylor, J.M.G. and Maciejewski, B. Acta Oncol. 27: 131-146, 1988) was reanalysed using a model which includes an explicit lag phase before the onset of tumour clonogen repopulation. A direct maximum-likelihood approach was used and the methodology extended to include the computation of profile-likelihood confidence limits. A statistically significant (p = 0.02) lag of 29 days was obtained with 95% confidence limits covering the range 17-31 days. However, the confidence interval was disconnected, and excluded the period 21-23 days. The analysis gave a time factor of 0.66 Gy/day. The mean values confirm the conclusions drawn by the original authors using a two-stage (indirect) method, and the values are similar to those calculated here for another data set comprising 496 patients (lag period = 26 (19-33) days). However, the data set itself is retrospective, and potentially subject to a number of biases. Therefore any clinical conclusions can only be tentative. A new feature of the methodology is the computation of profile-likelihood confidence limits and this will be useful in future direct analyses of clinical data of this type. The more usually computed normal approximation to the confidence limits have been shown to be inadequate in this analysis, and either profile-likelihood limits or likelihood ratio tests must be employed to determine the significance of the model parameters.

Head and Neck Neoplasms↗
PubMed1993

Biomechanical study of sternal closure techniques.

Median sternotomy is the most commonly used incision in cardiothoracic surgery. Closure of this incision is usually performed with parasternal wires, but alternate techniques have been proposed to improve closure stability. This study compares biomechanical stability of standard wire (No. 5 stainless steel) with that of three types of band closure: 5-mm Mersilene ribbon, 5-mm stainless steel band, and 5-mm plastic band. Eight bisected cadaver sterna were reapproximated using each method of sternal fixation and tested for biomechanical stability using an MTS Bionix 858 Biomechanical Tester. Loads of 50, 100, 150, and 200 Newtons (1 Newton = 1 kg.m/s2) were applied as a distracting force across the closure. A linear regression line of displacement as a function of increasing load was determined for each closure method; the slope of this line is inversely proportional to fixation stability. Displacement and load correlated linearly for each closure (r = 0.99). Mean slopes were 0.012 mm/Newton (95% confidence limits, 0.0098 to 0.0142 mm/Newton) for No. 5 stainless steel wire, 0.014 mm/Newton (95% confidence limits, 0.0118 to 0.0162 mm/Newton) for plastic band, 0.017 mm/Newton (95% confidence limits, 0.0148 to 0.0192 mm/Newton) for Mersilene ribbon, and 0.017 mm/Newton (95% confidence limits, 0.0148 to 0.0192 mm/Newton) for 5-mm steel band. No. 5 stainless steel wire provided the most stable closure, although statistical significance was achieved only in comparison with Mersilene ribbon and stainless steel band (p < 0.05). The superior stability of stainless steel wire closure may be due to tightening of the wires by twisting, which results in more tension across the reapproximated sternal halves than with other methods.

Biomechanical Phenomena↗
PubMed1997

Carpentier-Edwards pericardial valves in the mitral position: ten-year follow-up.

OBJECTIVE: The first generation of pericardial valves was withdrawn from the market because of a high rate of premature failure. With an original design, Carpentier-Edwards pericardial valves promised improved results. METHODS: One hundred fifty patients who underwent isolated mitral valve replacement, between July 1984 and December 1993, with Carpentier-Edwards pericardial bioprostheses in our institution were followed up. Patient mean age was 62.9 +/- 11.9 years. Operative mortality was 3.3%. All but three patients were followed up for an average of 4.7 years after operation, and total follow-up was 710 patients-years. RESULTS: At the time this article was written, over 80% of patients were in New York Heart Association class I or II. After 10 years, actuarial survival rate was 71% (confidence limit 61% to 81%). Valve-related complications included the following: six valve-related deaths (0.8% patient-year), five thromboembolic episodes (0.7% patient-year), three cases of endocarditis (0.4% patient-year), four reoperations (0.5% patient-year), and four structural valve failures with calcification and stenosis (0.5% patient-year). After 10 years, freedom from valve-related complications was 66% (confidence limit 46% to 86%), from valve-related death 94% (confidence limit 89% to 99%), from reoperation 90% (confidence limit 82% to 98%), and from valve failure 76% (confidence limit 62% to 90%). CONCLUSIONS: With a low rate of valve-related events at 10 years and a low rate of structural deterioration with no leaflet tear, this prosthesis is a reliable choice for patients over 60 years of age.

Adult↗
PubMed1994

Ebstein's anomaly: presentation and outcome from fetus to adult.

OBJECTIVES: This study was conducted to investigate the presentation and outcome of patients with Ebstein's anomaly of the tricuspid valve. BACKGROUND: Ebstin's anomaly may present at any age and has a highly variable clinical course. Previous natural history studies have been based on clinical and angiographic diagnosis and have included mainly older children and adults. Echocardiography, however, has facilitated fetal and neonatal diagnosis so that the natural history needs to be redefined. METHODS: We reviewed 220 cases of Ebstein's anomaly presenting from fetal to adult life between 1958 and 1991, with 1 to 34 years of follow-up. RESULTS: The most common presentation in each age group was abnormal routine prenatal scan for fetuses (86%), cyanosis for neonates (74%), heart failure for infants (43%), incidental murmur for children (63%) and arrhythmia for adolescents and adults (42%). Early presentation was frequently associated with other cardiac lesions, usually pulmonary stenosis or atresia. Surgery was undertaken at some stage in 86 (39%) of the 220 patients. Actuarial survival for all liveborn patients was 67% at 1 year and 59% at 10 years. There were 58 deaths, including 26 from heart failure, 19 perioperative and 8 sudden. Predictors of death included echocardiographic grade of severity at presentation (relative risk 2.7 for each increase in grade, 95% confidence limits 1.6 to 4.6), fetal presentation (6.9, confidence limits 1.6 to 16.5) and right ventricular outflow tract obstruction (2.1, confidence limits 1.1 to 4.4). Morbidity was mainly related to arrhythmias and late hemodynamic deterioration. Of 155 survivors, 129 (83%) were in functional class 1 and 104 (67%) were receiving no medical therapy. CONCLUSIONS: In Ebstein's anomaly, fetal and neonatal presentation is associated with a poor outcome and can be predicted by the echocardiographic appearance and presence of associated lesions. In older children and adults, incidental findings and arrhythmia are common and the long-term outcome is superior.

Adolescent↗
PubMed1988

Renal injury in sick newborn infants: a prospective evaluation using urinary beta 2-microglobulin concentrations.

Urinary concentrations of beta 2-microglobulin and creatinine were measured serially in 140 sick infants, of whom 109 were asphyxiated, and in 35 healthy preterm and term infants. First voided urines and samples from days 3 and 7 postpartum were studied. Urinary beta 2-microglobulin concentrations in healthy infants averaged 1.34 +/- 1.34 mg/L (mean +/- SD) in first voided specimens and 1.32 +/- 0.98 mg/L in day 3 samples; the calculated upper limit of normal (95% confidence limit) was 4.00 mg/L. Elevated values (those exceeding the 95% confidence limit) occurred most often in the sick asphyxiated patients (56%); the first voided sample value in these patients was 10.0 +/- 10.4 mg/L. The equivalent value in the sick nonasphyxiated infants was 8.32 +/- 7.27 mg/L. Values were significantly and persistently elevated in the sick infants on days 3 and 7. Factoring beta 2-microglobulin levels by urinary creatinine concentration did not affect the significance of the findings. The increased urinary beta 2-microglobulin levels were not (1) related to gestational age; low beta 2-microglobulin values occurred at all gestational ages for both healthy and sick infants; (2) a consequence of urine flow rate; urinary beta 2-microglobulin did not correlate with urinary creatinine concentration or with urine to plasma creatinine ratio; and (3) a consequence of increased production of beta 2-microglobulin; urinary and serum beta 2-microglobulin values did not correlate (r = .03). Thus, we propose that the elevated levels of urinary beta 2-microglobulin in the sick infants were the consequence of tubular injury. This was associated with hematuria but not with a high incidence of azotemia or oliguria.(ABSTRACT TRUNCATED AT 250 WORDS)

Asphyxia Neonatorum↗
PubMed1990

Influence of oxygenator type on the prevalence and extent of microembolic retinal ischemia during cardiopulmonary bypass. Assessment by digital image analysis.

We have previously reported the occurrence of microembolic ischemia in the retina during cardiopulmonary bypass, as revealed by fluorescein angiography. This method has been extended by digital image analysis to include quantification of the extent of retinal ischemia and has been applied to a prospective comparative study of 64 patients undergoing elective coronary operations with either a bubble or a membrane oxygenator. Patients with diabetes or clinically evident cerebrovascular disease were excluded. Bypass procedures were standardized in all cases with pulsatile flow and a 40 microns arterial line filter (Pall EC Plus). Thirty patients had bypass with a bubble oxygenator (Harvey H1700) and 34 patients had bypass with a flat sheet membrane oxygenator (COBE CML). In each case retinal fluorescein angiograms were obtained preoperatively and 5 minutes before the end of bypass and were processed with a digital image analyzer (Context Vision GOP-302). Microembolic perfusion defects were identified by digital subtraction of preoperative and end-bypass angiograms and their total area was computed. Results. In the bubble oxygenator group retinal perfusion defects indicative of microembolism occurred in all 30 (100%) patients. In contrast, over half the patients in the membrane oxygenator group had normal retinal perfusion, and the prevalence of perfusion defects (44%; 70% confidence limits 34% to 54%) was significantly less than in the bubble group (p less than 0.001). In addition, those patients in the membrane group had significantly fewer lesions (median 0; 70% confidence limits 0 to 1) than patients in the bubble group (median 2; 70% confidence limits 2 to 2; p less than 0.001) and also had significantly smaller total areas of retinal ischemia (median 0 mm2; 70% confidence limits 0 to 0.16 mm2) than the bubble group (median 0.22 mm2; 70% confidence limits 0.21 to 0.27 mm2; p less than 0.001). There was no relationship between the extent of retinal ischemia and bypass time, arterial blood gas concentrations, volume of cardiotomy suction or donor blood returned to the pump, or recent medication with aspirin. Inferences. Digital image analysis of retinal fluorescein angiograms may provide a method of quantifying microembolic ischemia in the central nervous system during cardiopulmonary bypass. Flat sheet membrane oxygenation appears to provide significantly better protection against microembolic ischemia than bubble oxygenation.

Blood Gas Analysis↗