Propofol or sevoflurane upon hemodynamic variables in dogs submitted to subarachnoid administration of iohexol.

摘要

The effects of propofol or sevoflurane on haemodynamic variables were studied in dogs submitted to myelography. 30 dogs were randomly divided into 2 groups, GP and GS. The GP animals were induced with propofol (10 mg kg-1) intravenously and intubated. Propofol was administered continuously through an infusion pump (0.55+or-0.15 mg kg-1 min-1). After 30 min, the liquor was collected on the magna cistern, and the contrast (iohexol) was injected. The same methodology was adopted for the GS animals, but sevoflurane at 2.5 MAC was used as the anaesthetic and induced by facial mask. The maintenance was done with 1.5 MAC. The variables studied were heart rate (HR), systolic, diastolic and mean arterial pressures (SAP, DAP, and MAP, respectively), cardiac output (CO), stroke volume (SV), central venous pressure (CVP), respiratory rate (RR), end tidal carbon dioxide (ETCO2) and oxyhaemoglobin saturation (SpO2). The measurements were done immediately after liquor collection (M1), after iohexol administration (M2), and at 10-min intervals after M2 for one hour. The numerical data were submitted to analysis of Variance (ANOVA), followed by F test considering p<0.05. Reduction in blood pressure was observed in both groups, but this effect was less intense in the group that received propofol. Reduction in HR and increase in CO and SV were observed in GS animals. Regarding the ETCO2, the averages obtained in GP were greater than those in GS. It was concluded that both propofol and sevoflurane did not promote haemodynamic alterations that compromised the myelography technique..