OBJECTIVES

The objective of this study has been to determinate the haemodynamic variables in dogs anaesthetized with the described protocol.

MATERIALS

Twenty-four clinically healthy dogs were anaesthetized during 120 minutes. The protocol used, was: atropine (10 mcg/kg), medetomidine (10 mcg/kg), propofol (2 mg/kg), and sevoflurane. A neuromuscular blockade was given every 40 minutes and dogs were ventilated with mechanical ventilation controlled by volume. To revert the effect of atracurium and go back to spontaneous ventilation, a mixture neostigmine-atropine was used. The haemodynamic variables studied by a non-invasive way were heart rate (HR), systolic, diastolic and mean blood pressure (SAP, DAP and MAP). By an invasive way, the systolic, diastolic and mean pressure in the femoral artery was monitored (ISAP, IDAP and IMAP). The cardiac pressures were also measured: central venous pressure (CVP), pulmonary arterial pressure (PAP) and wedge pressure (WP), introducing a Swan-Ganz catheter. The cardiac output (CO) was determined by the thermodilution method. These variables were registered every 5 minutes during the anaesthesia, except the cardiac output that was measured every 30 minutes during the anaesthesia.

RESULTS

The mean +- stand deviation registered values were: HR: 96+-23 lpm; SAP:127+-23 mmHg;DAP:86+-24 mmHg; MAP: 103+-24 mmHg; ISAP: 115+-23mmHg; IDAP: 82+-18 mmHg; IMAP: 92+-17 mmHg; CVP: 4+-3 mmHg; PAP: 12+-3 mmHg; APOP: 8+-4 mmHg; CO: 114+-32 ml/kg/min.

CONCLUSION

After the individual study of each variable during the anaesthesia, we can say that the haemodynamic variables were constant and within normal values.