Effect of proximal femoral osteoporosis on cementless hip arthroplasty: a short-term clinical analysis / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

<p><b>OBJECTIVE</b>The aim of this retrospective investigation was to explore the influence of femoral osteoporosis on short-term curative effects of cementless hip arthroplasty and to evaluate the femoral metaphyseal bone mineral density (BMD) for femoral osteoporosis in order to guide prosthesis choice and rehabilitation.</p><p><b>METHODS</b>We performed 127 total arthroplasty operations between June 1999 to February 2003 and investigated 49 cementless hip replacements with the Metalcancellous cementless Lubeck II system being used in all hips. There were twenty men and twenty-nine women whose mean age at the time of the operation was 60 years (range, 52~81 years). The patients were divided into osteoporosis or normal groups according to the femoral metaphyseal BMD measured preoperatively. The average duration of follow-up was 30 months (range, 8~52 months). We evaluated all of the patients from a clinical standpoint with use of a standard-terminology questionnaire with respect to the short-term curative effects and patients' satisfaction. Hip pain status and functional ability were important indicators of treatment efficacy.</p><p><b>RESULTS</b>Harris hip score and patients' satisfaction in femoral osteoporosis patients who underwent noncemented hip arthroplasty were lower (P=0.004, P=0.03) while the incidence of thigh pain was higher (P=0.03) than the patients with non-osteoporosis.</p><p><b>CONCLUSION</b>The higher incidence of pain, as well as the decrease in function experienced by the patients in osteoporosis group, supports the case that cementless arthroplasty is not a better choice for those patients and that we had better select prosthesis based on the femoral metaphyseal BMD.</p>

Dynamics of vascular volume and hemodilution of lactated Ringer's solution in patients during induction of general and epidural anesthesia / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

<p><b>OBJECTIVE</b>To investigate the dynamics of vascular volume and the plasma dilution of lactated Ringer's solution in patients during the induction of general and epidural anesthesia.</p><p><b>METHODS</b>The hemodilution of i.v. infusion of 1000 ml of lactated Ringer's solution over 60 min was studied in patients undergoing general (n=31) and epidural (n=22) anesthesia. Heart rate, arterial blood pressure and hemoglobin (Hb) concentration were measured every 5 min during the study. Surgery was not started until the study period had been completed.</p><p><b>RESULTS</b>General anesthesia caused the greater decrease of mean arterial blood pressure (MAP) (mean 15% versus 9%; P<0.01) and thereby followed by a more pronounced plasma dilution, blood volume expansion (VE) and blood volume expansion efficiency (VEE). A strong linear correlation between hemodilution and the reduction in MAP (r=-0.50; P<0.01) was found. At the end of infusion, patients undergoing general anesthesia retained 47% (SD 19%) of the infused fluid in the circulation, while epidural anesthesia retained 29% (SD 13%) (P<0.001). Correspondingly, a fewer urine output (mean 89 ml versus 156 ml; P<0.05) and extravascular expansion (454 ml versus 551 ml; P<0.05) were found during general anesthesia.</p><p><b>CONCLUSION</b>We concluded that the induction of general anesthesia caused more hemodilution, volume expansion and volume expansion efficiency than epidural anesthesia, which was triggered only by the lower MAP.</p>