Summary:Based on excellent results of successive single chest thumping (CT) and serial chest thumping (SCT) for the interruption of ventricular tachycardia (VT) in experimental animals with subacute myocardial infarction, the SCT method was applied for the treatment of VT in patients with coronary artery disease (CAD). SCT was successful in terminating 13 of 19 episodes of VT (68%) in 8 of 14 patients (57%). Conversion of VT was immediate in 9 episodes in 6 patients and latent in 4 episodes in 2 patients. Complications were rare but significant. In one case, SCT resulted in a ventricular asystole and in another case SCT accelerated the rate of VT from 167/min to 242/min, requiring electroconversion. Neither a short duration of VT nor a preserved left ventricular function seemed to enhance conversion by SCT. For interruption of VT in patients with CAD, SCT is not as successful as in the experimental animal model and, therefore, should not be used as a routine method. It may be applied in selected patients under hospital conditions with a standby defibrillator.

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Fat embolism syndrome (FES) during implantation of an uncemented resurfacing type of total knee replacement is the leading cause of postoperative mortality. A possible explanation might be the insertion of a solid intramedullary alignment rod, resulting in an intrafemoral pressure increase. On 45 cadaveric human femora we measured the resulting intramedullary pressure during insertion of three different alignment rods: a solid rod and a hollow shaped guiding rod, both 10 mm in diameter, and a fluted alignment rod of 8.5 mm in diameter. The highest intramedullary pressures occurred after placement of a solid 10 mm alignment rod (3.77 +/- 0.44 bar), followed by a fluted 8.5 mm rod (2.53 +/- 0.28 bar). In both cases, the increased pressure led to an extrusion of bone marrow contents through the venous system of the proximal femur. The least increase occurred after insertion of a hollow shaped alignment rod (0.26 +/- 0.03 bar) without any fat extrusion. Our study confirms the hypothesis that insertion of solid intramedullary alignment rods during preparation of the femoral shaft results in a dangerous pressure increase, so that embolization can occur. To minimize the risk of a FES, instruments should be modified in a manner, that only hollow shaped alignment rods are used.