View clinical trials related to Spinal Anesthetic Toxicity.
Filter by:In this study the investigators will compare two doses of norepinephrine bolus (6 mcg and 8 mcg) in management of maternal hypotensive episode after spinal block during cesarean delivery.
Modern guidelines have combined both the maximum diameter of IVC at expiration (dIVC max) and the IVCCI to appreciate right atrial pressure (RAP) measurements and consequently to assess intravascular volume status. In fact, IVC diameter <2.1 cm with IVCCI >20% (quite inspiration) suggests normal RAP of 3mmHg (range, 0-5mmHg), whereas IVC diameter >2.1 cm with IVCCI<20% suggests high RAP of 15mmHg (range, 10-20mmHg). In occasions where the IVC diameter and collapse is not fit the above categories, an intermediate value of 8 mmHg (range, 5-10 mmHg) is applied. From a clinical standpoint, it is conceivable that both measurements must be measured in isolation to enable RAP assessment. To circumvent this limitation the two indices have been consolidated to dIVCmax-to-IVCCI ratio. Although this ratio has been shown high accuracy to predict spinal-induced hypotension in elderly patients with preserved ejection fraction (EF) of the left ventricle (LV), its value in patients with cardiac dysfunction and reduced LV-EF has not been investigated. From the aforementioned, this study sets out to address the role of dIVCmax-to-IVCCI ratio in the prediction as well as in the management of hypotension after spinal anesthesia in elderly orthopaedic patients with reduced LV-EF.
In this study the investigators will compare two doses of norepinephrine bolus (6 mcg and 10 mcg) in management of maternal hypotensive episode after subarachnoid block during Cesarean delivery.
Study Protocol: Outcome Measurements Primary Outcome The main outcome will be the preoperative performance of the dIVCmax/IVCCI ratio to foresee the incidence of hypotension after spinal anesthesia in a greater extent to that of the established IVCCI measurements. Secondary Outcomes To identify other echocardiographic or clinical measurements that can predict an intraoperative spinal-induced haemodynamic instability. Sample Size Calculation A pilot study of 20 patients revealed a detected area under the ROC curve (AUC) of 0,91 for dIVCmax/IVCCI and for dIVCmax 0,82 with rank correlation between the two assays being 0.87 in both positive and negative cases. Based on this result, a sample of 56 patients will achieve 80% power to detect significant difference (at a level 0.05) between dIVCmax/IVCCI and dIVCmax. Potential Benefits of the Study The results of this study will allow us to determine which clinical or US-measurement can yield better performance so as a preoperative prediction of spinal-induced hypotension can be achieved; that way these measurements can permit and guide a targeted preoperative fluid challenges prior to the implementation of spinal anesthesia Potential Side Effects of the Study Participation in this protocol will not put patients at higher risk for complications since we do not perform any intervention (either pharmacological or surgical) There will be no occupational risks to researchers or assistants. Proposed Timetable According to the exclusion criteria and taking into account the number of cases performed in our department per monthly basis, it should take us approximately 6 months to recruit 60 patients.