Intravenous N-acetylcysteine versus intravenous theophylline in the prevention of contrast-induced nephropathy in critically ill patients: a prospective randomized clinical trial

Abstract

Aim Despite the use of several agents for prophylactic agents, contrast-induced nephropathy (CIN) remains a crucial clinical problem. The aim was to compare the efficacy of intravenous N-acetylcysteine (NAC) and intravenous theophylline in the prevention of CIN in critically ill patients. Patients and methods A total of 90 patients were admitted to the ICU with at least one risk factor for CIN and randomly divided into three groups. All patients received the regular management of renal protection with good hydration, to maintain adequate intravenous volume expansion with isotonic crystalloids (normal saline: 1–1.5 ml/kg/h) 3–12 h before the procedure, and it was continued for 6–24 h afterward. In the first group, patients received 6 mg theophylline intravenously over 30 min as a loading dose, followed by a maintenance dose of 0.5 mg/kg/h intravenously, to be started after the loading dose (group T). In the second group, patients received the full course of treatment with NAC (group A), which comprised three consecutive intravenous infusions: first infusion as initial loading dose of 150 mg/kg body weight infused in 200 ml over 1 h, followed by the second infusion of 50 mg/kg in 500 ml over the next 4 h, followed by the third infusion of 100 mg/kg in 1 l over the next 16 h (to be completed on the day of the examination). Control group: in this group, 30 patients received no additional drug before administration of radiocontrast medium. They only received the regular management of renal protection with good hydration. Results Despite the inclusion of ICU patients at high risk for CIN, we found a significant lower incidence of CIN and a lower incidence of patients requiring dialysis among patients under prophylaxis of intravenous NAC and intravenous aminophylline, as creatinine concentration was elevated by 25% in only four patients in the NAC group and only in three patients in the aminophylline group, and the incidence of CIN and patients requiring dialysis were significantly lower (P Conclusion We concluded that the administration of intravenous NAC or intravenous theophylline around the time of contrast administration prevents renal injury in equal efficacy compared with patients receiving no additional drugs at the time of contrast administration as regards incidence of nephropathy and incidence of dialysis among study patients.