Effect of sodium bicarbonate on blood lactate, blood pressure and inflammatory indexes after total hip replacement in elderly patients

Abstract

Objective To observe the effect of sodium bicarbonate on serum lactic acid (Lac) level, blood pressure and inflammatory indexes in elderly patients after total hip replacement. Methods We retrospectively analyzed the clinical data of 90 elderly patients undergoing unilateral total hip arthroplasty (THA) in our hospital between February, 2018 and November, 2018. Among these patients, 45 received intravenous infusion of 5% sodium bicarbonate (2 mL/kg) immediately after the operation, while the other 45 patients did not receive the treatment (control group). Blood gas analysis was performed and the heart rate (HR) and mean arterial pressure (MAP) were measured before (T0) and at 12 (T1), 24 (T2) and 48 h (T3) after sodium bicarbonate administration. Blood routines, C-reactive protein (CRP) level, and erythrocyte sedimentation rate (ESR) before and after the operation were assessed, and visual analogue scale (VAS) scores and Harris scores before and at 3 months after the operation were evaluated for each patient. Results The general baseline data were comparable between the 2 groups. The MAP and the level of lactic acid did not differ significantly between the 2 groups at T0, but were significantly lower in sodium bicarbonate group at T2 and T3 (P < 0.05). The pH value did not differ significantly between the 2 groups at T0, T1 and T3, but was significantly higher in sodium bicarbonate group at T2 (P < 0.05). The inflammatory parameters, which were comparable between the 2 groups before the operation, increased significantly after the surgery in both groups (P < 0.05), but were significantly lower in sodium bicarbonate group than in the control group (P < 0.05). In both groups, the Harris scores were increased (P < 0.05) and the VAS scores were decreased significantly at 3 months after the operation without significant difference between the 2 groups (P < 0.05). Conclusion Infusion of small-dose sodium bicarbonate can significantly reduce blood lactic acid level at 48 h after total hip replacement and helps to maintain postoperative hemodynamic stability, reduce postoperative inflammation and prevent complications in elderly patients.

Keywords

• artificial total hip replacement
• sodium bicarbonate
• lactic acid
• aged
• blood pressure
• inflammatory index