RESUMEN
BACKGROUND: Ondansetron was effectively used to prevent spinal anesthesia-induced hypotension in the general population and women anesthetised for cesarean section. The aim of this study was to test the hypothesis that blocking type 3 serotonin receptors with intravenous ondansetron administration reduces hypotension and bradycardia induced by spinal anesthesia in elderly patients. METHODS: Fifty-three patients participated in the study with 26 in the ondansetron group (received 8 mg intravenous ondansetron) and 27 in the placebo group (received 0.9% NaCl solution). The heart rate and arterial blood pressure were measured every 5 minutes after spinal anaesthesia, which was performed with 2.5 to 3 mL of 0.5% hyperbaric bupivacaine solution. RESULTS: Decreases in both the heart rate and mean systolic, as well as diastolic, arterial pressure compared to the baseline values were noted in both groups. The minimum diastolic and mean blood pressure values obtained over a 20-minute observation period were significantly higher in the ondansetron group. There were no significant differences in the systolic blood pressure and heart rate values between the groups. CONCLUSION: Administration of intravenous ondansetron prior to spinal anesthesia in geriatric patients attenuates the drop in the diastolic and mean arterial pressure without substantially affecting the systolic blood pressure.
Asunto(s)
Anestesia Raquidea/efectos adversos , Antieméticos/uso terapéutico , Hipotensión/prevención & control , Complicaciones Intraoperatorias/prevención & control , Ondansetrón/uso terapéutico , Anciano , Anciano de 80 o más Años , Antieméticos/administración & dosificación , Presión Sanguínea/efectos de los fármacos , Método Doble Ciego , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Hipotensión/fisiopatología , Complicaciones Intraoperatorias/fisiopatología , Masculino , Ondansetrón/administración & dosificaciónRESUMEN
Laryngoscopy and tracheal intubation may provoke changes of cardiac repolarisation. The aim of this study was to assess the effect of intravenous lidocaine on the ECG changes induced by laryngoscopy and tracheal intubation. Forty-three female patients were randomly allocated to receive lidocaine (1.5 mg.kg(-1)) or placebo immediately after induction of anaesthesia and changes in the ECG and arterial blood pressure were recorded. Correction of QT interval was calculated using Bazett's formula (QTcb), Fridericia's correction (QTcf), and Framingham formula (QTcF). Transmural dispersion of repolarisation (TDR) was determined as Tpeak-Tend time. There were no changes in the QTc value in the lidocaine group. In the placebo group, significant increases in QTcb, QTcf and QTcF values were observed after intubation compared to either control measurements or to comparative measurements in the lidocaine group. There were no significant differences in TDR either between or within the groups. Lidocaine diminishes prolongation of QTc, induced by tracheal intubation but there is no effect of intubation on TDR.