Influence of the perioperative administration of magnesium sulfate on the total dose of anesthetics during general anesthesia. A systematic review and meta-analysis.

BACKGROUND: Magnesium sulfate displays numerous characteristics that make it a useful drug in anesthesiology (N-methyl-d-aspartate receptor antagonist, vasodilator, antiarrhythmic, inhibitor of catecholamine release and of acetylcholine in the terminal motor plate). The perioperative use of this drug as an adjuvant capable of decreasing the required dose of anesthetics, has been proposed. OBJECTIVES: To assess the influence of intravenous magnesium sulfate administration during general anesthesia on the overall dose of required anesthetics. DESIGN: A systematic review of controlled randomized trials and meta-analysis. DATA SOURCES: An electronic bibliography search in MEDLINE and in the Cochrane Database of Controlled trials (CENTRAL) up to 2015. STUDY ELIGIBILITY CRITERIA, PARTICIPANTS AND INTERVENTIONS: Randomized, double-blind trials relating to general anesthesia in elective surgery using intravenous magnesium sulfate that provide information about the anesthetic requirements in ASA I and II patients. RESULTS: 20 clinical trials were selected for the qualitative analysis and 19 for the quantitative one. The use of perioperative intravenous magnesium sulfate reduces the requirement of the anesthetic, propofol during induction (-28.52mg; CI 95% -35.22-1.82; p<0.001) and maintenance (-213.56mg; CI 95% -322.93, -104.18; p<0.001) of anesthesia. Additionally, magnesium sulfate reduces the requirement of neuromuscular non-despolarizing blocking agents (-2.99mg; CI 95% -44.47, -1.99; p<0.001) and the intraoperative consumption of fentanile(-53.57 mcg; CI 95% -75.01, -32.12; p<0.001). CONCLUSIONS: We conclude that perioperative magnesium sulfate acts as a coadjuvant drug capable of reducing anesthetic requirements.

Comparison of 2 intravenous insulin protocols: Glycemia variability in critically ill patients. / Comparación de 2 protocolos de insulina intravenosa: variabilidad de la glucemia en pacientes críticos.

OBJECTIVE: Glycemic variability is an independent predictor of mortality in critically ill patients. The objective of this study was to compare two intravenous insulin protocols in critically ill patients regarding the glycemic variability. MATERIAL AND METHODS: This was a retrospective observational study performed by reviewing clinical records of patients from a Critical Care Unit for 4 consecutive months. First, a simpler Scale-Based Intravenous Insulin Protocol (SBIIP) was reviewed and later it was compared for the same months of the following year with a Sliding Scale-Based Intravenous Insulin Protocol (SSBIIP). All adult patients admitted to the unit during the referred months were included. Patients in whom the protocol was not adequately followed were excluded. A total of 557 patients were reviewed, of whom they had needed intravenous insulin 73 in the first group and 52 in the second group. Four and two patients were excluded in each group respectively. RESULTS: Glycemic variability for both day 1 (DS1) and total stay (DST) was lower in SSBIIP patients compared to SBIIP patients: SD1 34.88 vs 18.16 and SDT 36.45 vs 23.65 (P<.001). CONCLUSION: A glycemic management protocol in critically ill patients based on sliding scales decreases glycemic variability.