Shape Deviations of the Contact Areas of the Total Hip Replacement

Mechatronics ◽  
2011 ◽  
pp. 203-212 ◽  
Author(s):  
V. Fuis ◽  
M. Koukal ◽  
Z. Florian
1992 ◽  
Vol 68 (04) ◽  
pp. 436-441 ◽  
Author(s):  
Nigel E Sharrock ◽  
George Go ◽  
Robert Mineo ◽  
Peter C Harpel

SummaryLower rates of deep vein thrombosis have been noted following total hip replacement under epidural anesthesia in patients receiving exogenous epinephrine throughout surgery. To determine whether this is due to enhanced fibrinolysis or to circulatory effects of epinephrine, 30 patients scheduled for primary total hip replacement under epidural anesthesia were randomly assigned to receive intravenous infusions of either low dose epinephrine or phenylephrine intraoperatively. All patients received lumbar epidural anesthesia with induced hypotension and were monitored with radial artery and pulmonary artery catheters.Patients receiving low dose epinephrine infusion had maintenance of heart rate and cardiac index whereas both heart rate and cardiac index declined significantly throughout surgery in patients receiving phenylephrine (p = 0.0001 and p = 0.0001, respectively). Tissue plasminogen activator (t-PA) activity increased significantly during surgery (p <0.0005) and declined below baseline postoperatively (p <0.005) in both groups. Low dose epinephrine was not associated with any additional augmentation of fibrinolytic activity perioperatively. There were no significant differences in changes in D-Dimer, t-PA antigen, α2-plasmin inhibitor-plasmin complexes or thrombin-antithrombin III complexes perioperatively between groups receiving low dose epinephrine or phenylephrine. The reduction in deep vein thrombosis rate with low dose epinephrine is more likely mediated by a circulatory mechanism than by augmentation of fibrinolysis.


1991 ◽  
Vol 66 (06) ◽  
pp. 652-656 ◽  
Author(s):  
Per Anders Flordal ◽  
Karl-Gösta Ljungström ◽  
Jan Svensson ◽  
Brenda Ekman ◽  
Gustaf Neander

SummaryTwelve patients undergoing total hip replacement, with regional anaesthesia and with dextran infusion for plasma expansion and thromboprophylaxis, were given the vasopressin analogue desmopressin (DDAVP) or placebo in a randomized, double-blind prospective study. In controls (n = 6) we found a prolongation of the bleeding time, low factor VIII (FVIII) and von Willebrand factor (vWF) and a decrease in antithrombin III to levels known to be at risk for venous thrombosis. Desmopressin shortened postoperative bleeding time, gave an early FVIII/vWF complex increase, prevented antithrombin III from falling to critically low values and appeared to activate the fibrinolytic system, both by tPA increase and PAI-1 decrease.Thus in the controls we found changes in both coagulation and fibrinolysis indicating a haemorrhagic diathesis as well as a risk for thromboembolism. Desmopressin induced factor changes that possibly reduce both risks.


1976 ◽  
Vol 36 (01) ◽  
pp. 157-164 ◽  
Author(s):  
P. M Mannucci ◽  
Luisa E. Citterio ◽  
N Panajotopoulos

SummaryThe effect of subcutaneous low-dose heparin on postoperative deep-vein thrombosis (D. V. T.) (diagnosed by the 125I-labelled fibrinogen test) has been investigated in a trial of 143 patients undergoing the operation of total hip replacement. Two randomized studies were carried out: in one the scanning for D.V.T. was carried out daily for 7 days post operatively and in the other for 15 days. In both, the incidence of D.V.T. was significantly lower in the heparin-treated patients (P<0.005). Bilateral D.V.T. was also prevented (P<0.05), through the extension of D.V.T. to the distal veins of the thigh was not significantly reduced. Heparin treatment was, however, followed by a higher incidence of severe postoperative bleeding (P< 0.02) and wound haematoma formation (P< 0.005), and the postoperative haemoglobin was significantly lower than in the control group (P<0.005). A higher number of transfused blood units was also needed by the heparin treated patients (P<0.001).


2019 ◽  
Vol 85 (3) ◽  
Author(s):  
Gianluca Cappelleri ◽  
Daniela Ghisi ◽  
Andrea L. Ambrosoli ◽  
Alice Ascari ◽  
Elisa Compagnino ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document