BACKGROUND: A tourniquet is commonly used to achieve a bloodless field in surgery of the extremities. However, the anesthesiologist is concerned about the adverse effects of hypertension which occur during general anesthesia. In this study, we assessed the effects of lidocaine infiltration in the tourniquet site on blood pressure and heart rate during tourniquet inflation under general anesthesia. METHODS: Forty patients of ASA class I or II, scheduled for knee surgery, were randomly divided into two groups. In group 1 underwent general anesthesia and in group 2 also underwent general anesthesia and combined with 1% lidocaine infiltration in the tourniquet site. The changes of systolic and diastolic blood pressure and heart rate were measured before and after toumiquet inflation, after skin incision and 30 min after inflation. RESULTS: Comparing group 1 with group 2, there were significant increases after tourniquet inflation to 30 min after inflation in systolic and diastolic blood pressure in group 1 (p<0.05). However, there were no significant changes in heart rates in either group. CONCLUSIONS: The above results demonstrate that patients who received lidocaine infiltration in the tourniquet site showed less increase in blood pressure during tourniquet inflation.
Anesthesia, General ; Anesthetics ; Blood Pressure* ; Extremities ; Heart Rate* ; Heart* ; Humans ; Hypertension ; Inflation, Economic ; Knee ; Lidocaine* ; Skin ; Tourniquets*