BLOOD TRANSFUSION: A POSSIBLE RISK FACTOR IN RETROLENTAL FIBROPLASIA

ABSTRACT. Clark, C, Gibbs, J. A. H., Maniello, R., Outerbridge, E. W., and Aranda, J. V. (Department of Newborn Medicine, McGill University, Montreal Children's Hospital Research Institute, Montreal, Quebec, Canada). Blood transfusion: A possible risk factor in retrolental Fibroplasia. Acta Paediatr Scand, 70:535,.–The effect of blood transfusion on the occurrence of RLF was evaluated in 58 infants who weighed less than 1 001 g at birth (Group I) and 70 oxygen treated infants of various birth weights (Group 11). Although there was no significant difference between Group 1 infants with or without exchange transfusion as to birth weight, gestational age, duration of oxygen therapy, peak Po₂'s, or multiple births, there was a significantly increased incidence of pre-retrolental fibroplasia in transfused over non-transfused Group II infants. When Group II infants were stratified for prematurity and oxygen duration, this difference persisted in those not already at risk for RLF. This increased incidence of retinopathy in transfused infants suggests that blood transfusion may be a risk factor in the pathogenesis of RLF.     

Nationwide linkage analysis in Scotland implicates age as the critical overall determinant of mortality in ulcerative colitis

Aliment Pharmacol Ther 31 , 1310–1321

Summary

Background Recent data associated higher mortality with medical rather than surgical intervention in patients with ulcerative colitis who require hospitalization. Aim To examine factors influencing UC‐related mortality in Scotland. Method Using the national record linkage database 1998–2000, 3‐year mortality was determined after four admission types: colectomy‐elective or emergency; no colectomy‐elective or emergency. Results Of 1078 patients, crude 3‐year mortality rates were: colectomy elective 5.6% (n = 177) and emergency 9.0% (100); no colectomy elective 9.8% (244) and emergency 16.0% (557). Using elective colectomy as reference, multivariate analysis [OR (95% CI)] showed that admission age >50 years [OR 5.46 (2.29–11.95)], male gender [OR 1.92 (1.23–3.02)], comorbidity [OR 2.2 (1.38–3.51)], length of stay >15 days [OR 2.04 (1.08–3.84)] and prior IBD admission [OR 1.66 (1.06–2.61)] were independently related to mortality. Age was the strongest determinant. No patient <30 years died. Mortality of patients aged <50 years [10/587 (1.7%)] was significantly lower than mortality of those aged 50–64 years [26/246 (10.6%)] (χ² = 32.91; P < 0.0000001) and >65 [96/245 (39.2%)] (χ² = 218.2; P < 0.0000001). For those patients aged more than 65 years, mortality in the four groups was 29.4%, 33.3%, 28.1% and 44.7%– all greater than expected in the Scottish population on assessment of standardized mortality ratios. Conclusion Hospital admission in UC patients >65 is associated with high mortality. Management strategies should consider this by treatment in specialist units, early investigation, focused medical treatment and earlier surgical referral.     

Histopathologic Alterations in the Decidua in Human Spontaneous Abortion: Loss of Cells With Large Cytoplasmic Granules

ABSTRACT: The histopathology of decidua obtained from the placental bed was evaluated by phloxine-tartrazine staining, which allows clear definition of cells with cytoplasmic granules. Mononuclear cells with large granules were seen in biopsy specimens taken from women at 8–31 weeks of normal pregnancy. In contrast, cells with large granules were missing in sections taken from the decidua of five women who were aborting or were destined to abort. Since the presence of suppressor cell activity in murine decidua correlates with the success of pregnancy and since this suppression is associated with small lymphocytes with cytoplasmic granules, the observations made using human placental bed biopsy material suggest that a possible suppressor cell deficiency might occur in the early stages of spontaneous abortion in human females.     

Monophasic Versus Biphasic Cardiac Stimulation: Mechanism of Decreased Energy Requirements

The purpose of the present study was to examine the effects of monophasic and biphasic stimulation under conditions of full and incomplete repolarization in an in vivo dog model and in an in vitro rabbit ventricular single cell model. Strength-interval curves were constructed with monophasic cathodal stimulation and biphasic subthreshold anodal followed by cathodal stimulation in dogs prior to and late after left anterior descending coronary artery occlusion. At the monophasic absolute refractory period plus 10 msec, less cathodal current was required for biphasic compared to monophasic stimulation (P = 0.04). Moreover, the biphasic absolute ventricular refractory period (116 +/- 8 msec) was significantly shorter than the monophasic absolute ventricular refractory period (136 +/- 15 msec) (P less than 0.02). At coupling intervals greater than 30 msec after the monophasic absolute ventricular refractory period, there was no distinction between monophasic and biphasic stimuli. Similarly enhanced excitability was observed with biphasic stimuli in infarcted hearts. Voltage clamp measurements mimicking conditions of the in vivo studies demonstrated that when repolarization is incomplete, a hyperpolarizing prepulse reactivates additional sodium current resulting in enhanced excitability. In conclusion, biphasic stimulation consisting of a hyperpolarizing anodal prepulse followed by a cathodal pulse decreases the current required for excitation compared to cathodal monophasic stimulation in a critical zone near the ventricular absolute refractory period.