The Effect of Bilateral Femoral Nerve Block Combined with Intravenous Patient-controlled Analgesia after a Bilateral Total Knee Replacement / 대한통증학회지

BACKGROUND: Postoperative pain after bilateral total knee replacement (TKR) is expected to be more severe than unilateral TKR. Intravenous patient-controlled analgesia (IV PCA) is less effective than other methods of pain management especially immediately after an operation even though it is an easily controlled method for managing pain. This study was designed to evaluate the effect of femoral nerve blocks combined with IV PCA after bilateral TKR for postoperative pain control. METHODS: The patients in group I (n = 20) were given only IV PCA with morphine and group II (n = 20) were given bilateral femoral nerve blocks with 12 ml of 0.25% bupivacaine and epinephrine 1: 400,000 before extubation followed by an IV PCA. Main outcome measures included numerical rating pain score, cumulative opioid consumption, hourly dose during each time interval, and side effects. RESULTS: The pain score in group II was significantly lower than that in group I immediately after recovery of awareness and at 3, 6, 12 hours postoperatively. Cumulative opioid consumption was significantly decreased in group II during the first 48 hours postoperatively. The hourly dose in group II was also significantly lower than that in group I until 12 hours postoperatively. There was no difference in side effects between the groups. CONCLUSIONS: We concluded that bilateral femoral nerve blocks improve analgesia and decrease morphine use during IV PCA after bilateral TKR.

Hemodynamic Changes using Partial CO2 Rebreathing Method and Esophageal Doppler Monitor during Bilateral Total Knee Replacement Arthroplasty / 대한마취과학회지

BACKGROUND: We studied hemodynamic changes using a noninvasive partial CO2 rebreathing cardiac output method (NICO) and esophageal Doppler monitor (EDM), and metabolic changes in elderly patients undergoing bilateral total knee replacement arthroplasty (BTKA). METHODS: Twenty patients undergoing BTKA were studied. Hemodynamic and metabolic parameters were measured before tourniquet inflation (TI), 0, 3, 6, 9, 15, 30, 45 min after TI, and 0, 3, 6, 9, 15, 30 min after tourniquet deflation (TD) and skin suture. Stroke volume (SV), cardiac output (CO) and systemic vascular resistance (SVR) were measured using NICO and EDM. RESULTS: Mean blood pressure (MBP), central venous pressure (CVP), and SVR had significant increases in TI, and decreases in TD compared with value measured before TI (baseline value). Especially, MBP had higher decrease in the second tourniquet compared with first tourniquet, SV and CO were decreased in TI, and increased in TD compared with baseline value, HR had significant increases in the TD of second tourniquet. pH and lactate were shown significantly lower values at the second tourniquet compared with the first tourniquet (P < 0.05). The bias and precision derived from CO between EDM and NICO was 0.27 +/- 0.41 L/min, and CO by NICO was smaller than that by EDM. The correlation coefficient between NICO and EDM was calculated to be 0.43. CONCLUSIONS: MBP, SV, CO, pH and lactate were shown to be higher in the second tourniquet in BTKA. NICO showed lower CO compared with EDM after TD in patients undergoing BTKA, but statistically insignificant at most measurement.