Comparison of Oral and Intravenous N-acetyl Cysteine in Preventing Contrast Nephropathy.

INTRODUCTION: Despite high rates of morbidity and mortality in patients with contrast-induced nephropathy (CIN), there is no consensus regarding prevention of this well-known complication of contrast media use. One agent that has been widely used in this regard is N-acetyl cysteine (NAC). Nevertheless, its efficacy is still controversial. The aim of this study was to assess the efficacy of NAC, both in the oral and intravenous forms, for the prevention of CIN. METHODS: This study is a double-blind randomized placebo controlled clinical trial. We randomized 434 adult patients with chronic kidney disease (constant serum creatinine ≥1.5 mg/dL) who were candidates for coronary angiography/plasty. The patients were categorized into three groups. One group received 1,200 mg NAC intravenously half an hour before the procedure and oral placebo starting 3 days before angiography. The second group received oral NAC 600 mg twice daily for 3 days, starting the day before the intervention and intravenous placebo half an hour before intervention. The third group received both oral and intravenous placebo. CIN was defined as a 25% relative increase in serum creatinine from baseline value, 48 h after use of contrast medium. RESULTS: Of the 434 patients, 149 received intravenous NAC, 145 received oral NAC, and the remaining 140 received placebo. The incidence of CIN in the three groups was 6.1%, 7.6%, and 10.8%, respectively (p = 0.34). CONCLUSION: In patients with chronic kidney disease, neither intravenous nor oral NAC is superior to placebo for preventing CIN.

A comparison of definitions of contrast-induced nephropathy in patients with normal serum creatinine.

Contrast-induced nephropathy (CIN) is the third leading cause of acute kidney injury in hospitalized patients. The prevalence of CIN is reported to range from 0% to 50%, depending not only on patient condition and the procedure used but also the definition of CIN applied. We aimed to determine the best diagnostic indicator of CIN in patients with normal serum creatinine. This study included 206 patients with normal serum creatinine who underwent coronary angiography/angioplasty. Serum creatinine level and glomerular filtration rate (GFR) were measured before and on the second and fifth days after contrast administration. The incidence of CIN based on a 25% increase in serum creatinine was calculated and compared with the incidence based on a 25% decrease in GFR or an increase of at least 0.5 mg/dL in serum creatinine. Of 206 patients, 127 were male (61.7%) and 79 were female (38.3%); the mean age was 59.56±10.3 years. The prevalence of CIN was 30% based on a 25% increase in serum creatinine, 23% based on a 25% decrease in GFR (P<0.012) and 3.8% based on a serum creatinine increase of at least 0.5 mg/dL (P<0.0001). The serum creatinine levels remained within the normal range in the majority of patients with CIN based on the different definitions. In patients with normal serum creatinine, the absolute increase in serum creatinine may describe the prevalence of CIN more accurately than the relative increase in serum creatinine or relative decrease in GFR.

The effect of magnesium sulphate on postoperative analgesia requirements in gynecological surgeries.

OBJECTIVE: Recent studies have shown the positive effect of magnesium sulphate (MgSO4) on pain reduction and postoperative analgesic requirements in patients undergoing surgery. We assessed the effect of MgSO4 on intra-operative and postoperative analgesic requirements in patients undergoing lower abdominal gynecological laparotomy. MATERIALS AND METHODS: This randomized clinical trial was conducted on 30 female patients at Rasool-e-Akram (referral and academic) hospital in Tehran from August 2012 to March 2013. The patients who were candidates for gynecologic surgeries (hysterectomy and/or myomectomy) were randomized into study (n=15) and control (n=15) groups. Same anesthetic technique was used in all patients. Besides induction of the anesthesia in the study group, we administered MgSO4 50 mg/kg/hr intravenously (IV) for analgesic purposes as a bolus dose and then 8 mg/kg IV as maintenance dose. Control group received the same anesthetic agents and the same amount of isotonic saline instead of MgSO4. Analgesic consumption was measured in both groups postoperatively within 24 hours. The visual analog scale (VAS) was used for the evaluation of postoperative pain in both groups. RESULTS: There was a decrease in analgesic consumption and pain in the group receiving MgSO4, in comparison to control group. Pain severity assessment, 24 hours post operatively showed similar results in both groups. There was a statistically significant difference in prescribed dose of pethidine between study and control groups (p=<0.0001). CONCLUSION: Intra-operative MgSO4 is effective in postoperative pain control following lower abdominal laparotomy. Further studies with larger sample sizes and longer follow-up should be performed to obtain more information about safety and to determine whether doses of MgSO4 can provide postoperative analgesic benefits.

The influence of dexamethasone on postoperative nausea and vomiting in patients undergoing gynecologic laparoscopic surgeries: A randomised, controlled, double blind trial.

OBJECTIVE: Dexamethasone, as a part of multimodal approach, can decrease nausea and vomiting following laparoscopy in high risk patients. We performed this study to find out whether the dexamethasone can improve postoperative nausea and vomiting (PONV) in patients undergoing gynecology laparoscopic surgeries. MATERIALS AND METHODS: In this double-blind randomized clinical trial, 91 patients who underwent gynecologic laparoscopic surgery in Rasool Akram hospital in Tehran during 2011-2014 were enrolled. Fourty-four patients received 8 mg dexamethasone (study group) and 47 patients received 10 mg metochlopramide (control group) intravenously after intubation. Outcome parameters including age, weight, height, cause of hospitalization, drugs, Last Menstrual Period (LMP), Blood Pressure (BP), Heart Rate (HR), Respiratory Rate (RR) and oxygen saturation, Visual Analogue Scale (VAS) score, nausea and vomiting were entered to SPSS (v.16) and were analyzed. RESULTS: Eighyt-eight American Society of Anesthesiology (ASA) class 1-2 patients between 25-39 years old were analyzed. There was no difference in vital signs during and post operation (BP, HR, RR and O2 saturation) between these two groups (p value>0.05). There was no significant difference between VAS score at 4 and 24 hours after the operation (14% vs. 17.8% and 7% vs. 6.7%, respectively, p>0.05). Incidence of PONV in 4 hours was significantly lower in dexamethasone group (11.6% vs. 55.6% p<0.0001), while there was no significant difference in 24 hours (23.3% vs. 22.2%, p>0.05) and also need to anti-emetic drugs wasn't significantly lower in study group (p>0.05). CONCLUSION: We conclude that dexamethasone can relieve PONV after gynecologic laparoscopic surgery.