Effects of magnesium sulphate on the onset time of rocuronium at different doses: a randomized clinical trial.

BACKGROUND AND AIMS: Rocuronium may provide excellent onset time, but high doses are required for effective action. Several strategies have managed to shorten rocuronium onset time, including the use of Magnesium Sulphate (MgSO4). METHODS: One hundred and eighty patients were randomized into six groups according to rocuronium dose received (0.3, 0.6 or 1.2 mg.kg-1) and the administration of saline or MgSO4 (60 mg.kg-1). Correlations between tissue perfusion and rocuronium onset time was determined by variations in perfusion index. RESULTS: Median (quartiles) rocuronium onset times were 85.5 (74.0-92.0); 76.0 (52.0-87.0) and 50.0 (41.0-59.5) seconds for 0.3, 0.6 mg.kg-1 and 1.2 mg.kg-1 doses, respectively. MgSO4 decreased rocuronium onset at doses of 0.3 mg.kg-1 (60.0 [48.0-74.3] seconds) and 0.6 mg.kg-1 (44.0 [39.0-49.0] seconds) but not at 1.2 mg.kg-1 (38.0 [33.5-56.3] seconds) (p < 0.001). Perfusion index variations in groups that received MgSO4 were greater than in controls. A negative correlation between shorten onset and increased perfusion index was observed in rocuronium doses of 0.3 mg.kg-1 (r = -0.50; p < 0.001) and 0.6 mg.kg-1 (r = -0.424; p < 0.001), but not for 1.2 mg.kg-1 dose (r = -0.25; p = 0.07). CONCLUSION: MgSO4 reduces rocuronium onset time at doses of 0.3 mg.kg-1 and 0.6 mg.kg-1 being that the latter has a similar effect when compared to the dose of 1.2 mg.kg-1, with or without the use of MgSO4. TRIAL REGISTRY AT: http://www.ensaiosclinicos.gov.br/ REGISTRY NUMBER: RBR-96CY3K.

Effects of pneumoperitoneum on kidney injury biomarkers: A randomized clinical trial.

BACKGROUND: Increased intra-abdominal pressure causes hemodynamic changes that may affect renal biomarkers. METHODS: This randomized, single-blind, single-center clinical trial recruited patients undergoing laparoscopic cholecystectomy at a tertiary care center in Brazil. They were randomly allocated to a standard intra-abdominal pressure group (P10-12, 10-12 mm Hg) and a low intra-abdominal pressure group (P6-8, 6-8 mm Hg). The primary outcome was the change in neutrophil gelatinase-associated lipocalin (NGAL) and cystatin C levels measured at the beginning of the procedure (T0), at the end of the procedure (T1), and 24 hours after the procedure (T2). P-values < 0.05 were considered statistically significant. RESULTS: In total, 64 patients completed the study-33 were given standard pressure and 31 were given low pressure. There was no significant difference in the biomarker between the groups (P = 0.580), but there was a significant difference between the time points with elevation at T1 (P < 0.001). Similar to NGAL, cystatin C had an elevation at T1 in both groups (P = 0.021), but no difference was found when comparing the groups. CONCLUSIONS: In laparoscopic cholecystectomy, pneumoperitoneum increases NGAL and cystatin C levels intraoperatively, and the use of low-pressure pneumoperitoneum does not change the course of these biomarkers.

Cyclosporine A attenuates apoptosis and necrosis after ischemia-reperfusion-induced renal injury in transiently hyperglycemic rats.

PURPOSE:: To investigate the effects of cyclosporine A on renal ischemia-reperfusion injury during transient hyperglycemia in rats. METHODS:: In a model of ischemia-reperfusion-induced renal injury and transiently induced hyperglycemia by intraperitoneal injection of glucose, 2.5 g.kg-1, Wistar rats were anesthetized with either isoflurane or propofol and received intravenous cyclosporine A, 5 mg.kg-1, five minutes before reperfusion. Comparison groups were isoflurane and propofol sham groups and isoflurane and propofol ischemia-reperfusion-induced renal injury. Renal tubular cell viability was quantitatively assessed by flow cytometry after cell culture and classified as early apoptosis, necrotic cells, and intact cells. RESULTS:: Early apoptosis was significantly higher in isoflurane and propofol anesthetized animals subjected to renal ischemia-reperfusion injury when compared to both cyclosporine A treated and sham groups. Necrosis percentage was significantly higher in propofol-anesthetized animals subjected to renal ischemia-reperfusion injury. The percentage of intact cells was lower in both, isoflurane and propofol anesthetized animals subjected to renal ischemia-reperfusion injury. CONCLUSION:: In a model of ischemia-reperfusion-induced renal injury, cyclosporine A, 5 m.kg-1, administered five minutes before renal reperfusion in rats with acute-induced hyperglycemia under either isoflurano or propofol anesthesia, attenuated early apoptosis and preserved viability in renal tubular cells, regardless of the anesthetic used.

Acute kidney function and morphology following topload administration of recombinant hemoglobin solution.

There is a 0.138% incidence of adverse reactions related to blood transfusion. Transfusion-related acute lung injury, immunosuppression, fever, pathogen transmission, and hemolytic transfusion reactions are the most common ones. Synthetic oxygen carriers have been developed to deal with blood shortages and for use in the field where stored blood was not available. They were also designed to be pathogen free, including unknown viruses. In this study, we used Male Golden Syrian Hamsters implemented with a dorsal window chamber to determine how infusion of three different, genetically crosslinked recombinant acellular hemoglobin (rHb) solutions with different oxygen affinities and nitric oxide kinetics affect mean arterial pressure (MAP), heart rate (HR), kidney function, and kidney structure. We found that the administration of all three rHb solutions caused mild hypertension and bradycardia 30 minutes after infusion. However, acute changes in glomerular filtration rate (GFR) were not detected, even though histological analysis was performed 72 hours after treatment revealed some structural changes. All the rHb solutions resulted in hypertension 30 minutes after a 10% topload administration. Regardless of their properties, the presence of acellular Hb causes significant alterations to kidney tissue.

[The use of dexmedetomidine in neurosurgery.]. / Uso de dexmedetomidina em neurocirurgia.

BACKGROUND AND OBJECTIVES: The use of alpha2-adrenergic agonists is increasingly more frequent in Anesthesiology, as adjuvant or the sole anesthetic drug. Currently, dexmedetomidine is gaining popularity due to its greater selectivity for the alpha2-adrenergic receptors and its pharmacokinetic profile. The aim of this review was to analyze the use of dexmedetomidine in neurosurgery. CONTENTS: Besides considerations and review of the literature regarding the use of dexmedetomidine, specifically in neurosurgical procedures, its effects on the different organ systems are described. CONCLUSIONS: The pharmacokinetic and pharmacodynamic profile of dexmedetomidine favors its use in several neurosurgical procedures. Its use in craniotomy for the treatment of aneurysms and tumor removal is recent. Besides, its use in functional surgical interventions is promising.