عبدالرضا رجایی فر

Premature rupture of membranes (PROM) affects 10-20% of all pregnancies, occuring in approximately 30% to 40% of preterm deliveries. Vitamin C has a role in collagen metabolism and increases resistance maintenance of the chorioamniotic membranes. The objective of this study was to evaluate the relationship between vitamin C supplementation with PROM and preterm delivery.Methods and Materials: This clinical-trial study carried out from Jan to Jul 2006 at Hafez and Shoushtari Hospitals of Shiraz University of Medical Sciences. This study was approved by the local committee of medical ethics. Pregnant women (n=117) with 20 weeks gestational age, randomly divided into two groups 57 in the case group and 60 in the control group and evaluated every 4 weeks, from 20 to 36 weeks of pregnancy. At each evaluation, a vaginal examination was performed, to rule out bacterial vaginosis infection. The case group received a chewing tablet of 100 mg vitamin C daily. PROM and preterm delivery was recorded for each group as indicator of the protective effect of vitamin C supplementation. PROM occurred in 5 (8.77%) and 22 (36.67 %) pregnancies in the case and control group respectively (p<0/001). Four patients (7.41%) in the case group and 18 pregnant women (32.08 %(in the control group delivered at term with PROM (p=0.001). One woman (33.30%) in the case group and 4 women (57.10 %(in the control group delivered due to PROM at term (p> 0.5). Supplementation of vitamin C after 20 weeks of gestation prevents PROM.

Hypotension is the most frequent adverse event during hemodialysis. Cool dialysate is a simple and cost effective measure in treating intradialytic hypotension by stabilization of core body temperature. This study was designed to find out the effects of cool dialysate on the frequency of intradialytic hypotension, presenting symptoms and intervention measures used for patients undergoing hemodialysis

In this randomized cross-over clinical trial, patients with intradialytic hypotension were detected based on the pre-defined inclusion criteria. Then, they were randomly assigned to treatment (cool dialysate) and control (conventional dialysis) groups. After 1 month, they crossed over as control and treatment groups.

Data analysis (paired t-test) revealed that cool dialysate was associated with decrease in frequency of hypotension and number of interventions while improving symptoms and an increment in systolic and diastolic blood pressure.

Cool dialysate is an effective tool in maintaining intradilaytic hemodynamic stability, alleviating symptoms of hypotension and the interventions applied for intradialysate hypotension. Therefore, cool dialysate is recommended in hemodialysis patient.