ABSTRACT
The influence of treatment with an activated prothrombin complex preparation (FEIBA) on the antibody level was studied in 10 haemophiliacs with an antibody to factor VIII. The antibody level was observed to rise at least once in five patients, while in the remaining five patients no rise occurred. In all, 6 out of 31 treatments were followed by an anamnestic rise of the antibody level, corresponding to 19.4%. A rise of the inhibitor level following FEIBA treatment is likely to occur in patients who show a marked antibody rise after factor VIII treatment (good responders), but have a low antibody level at the time of treatment. High doses of FEIBA and simultaneous of red cells may also enhance the likelihood of an anamnestic response. Stimulation of antibody production is probably due to the presence of small amounts of factor VIII in this preparation.
Subject(s)
Antibodies , Factor VIII/immunology , Hemophilia A/therapy , Prothrombin/therapeutic use , Antibody Formation , Blood Transfusion , Erythrocyte Transfusion , Factor VIII/therapeutic use , Humans , Immunologic Memory , Time FactorsABSTRACT
In an experimental study on 22 adult Elco rabbits, hemodynamic parameters were investigated using a working heart model. The study group (10 rabbit hearts) received 1 mg/kg i.v. of the phosphodiesterase inhibitor piroximone 15 min before thoracotomy. 12 untreated rabbit hearts served as a control group. Hemodynamic parameters were measured before and after 60 min of hypothermic ischemia. The pre-ischemic period showed no significant differences between the two groups, except the higher levels of coronary flow in the piroximone group. The postischemic period showed significant increases in heart rate, coronary flow, aortic flow and cardiac output in the piroximone group in comparison to the control group. These results indicate as a main effect the positive influence of piroximone on coronary flow, given as a single shot 15 min preoperatively. This study provides evidence of the vasodilative properties on the coronary arteries beside the documented effects on the periphery. Therefore, piroximone represents an alternative tool in weaning from the cardiopulmonary bypass.
Subject(s)
Heart/physiopathology , Imidazoles/administration & dosage , Phosphodiesterase Inhibitors/administration & dosage , Reperfusion Injury/prevention & control , Animals , Heart/drug effects , Hemodynamics/drug effects , Rabbits , Reperfusion Injury/physiopathologyABSTRACT
In a randomized prospective experimental study on 48 adult white Elco rabbits biochemical and rhythmic changes after bolus administration of the phosphodiesterase inhibitor piroximone were investigated using a working heart model. The treatment group (n = 21) intravenously received 1 mg/kg of piroximone 15 min before thoracotomy. Twenty-three untreated hearts served as the control group. From 6 hearts of each group myocardial biopsies were taken before ischemia, 4 (2/2) hearts were excluded. Hemodynamic results of a previous study with an identical protocol were reanalyzed; a biochemical analysis of myocardial high-energy phosphates was investigated after 60 min of global ischemia and at the end of the experiments after 45 min of reperfusion. Already prior to ischemia, in the treatment group depletion of high-energy phosphates was detected. After 60 min of ischemia during early reperfusion in the treatment group ATP and creatine phosphate depletion became even more evident and increased until the end of the experiments. The incidence of reperfusion-induced arrhythmias was significantly lower in the treatment group. Consequently these results and the hemodynamic results of prior studies indicate a possible positive effect of piroximone during the early reperfusion period by optimizing hemodynamics and arrhythmias.
Subject(s)
Adenosine Triphosphate/metabolism , Heart/drug effects , Imidazoles/pharmacology , Myocardial Ischemia/metabolism , Phosphocreatine/metabolism , Phosphodiesterase Inhibitors/pharmacology , Animals , Arrhythmias, Cardiac/epidemiology , Arrhythmias, Cardiac/etiology , Heart/physiopathology , In Vitro Techniques , Incidence , Myocardial Ischemia/pathology , Myocardial Ischemia/physiopathology , Myocardial Reperfusion , Myocardial Reperfusion Injury/complications , Myocardium/metabolism , Myocardium/pathology , RabbitsABSTRACT
In the present study the effect of oxygenated Bretschneider cardioplegia on high-energy phosphates [adenosine triphosphate (ATP), adenosine diphosphate (ADP) and creatine phosphate (CP)] and hemodynamics was evaluated in the isolated working rabbit heart. Hearts were obtained from 37 adult white Elco rabbits (3,100 +/- 110 g). After a 20-min working period 14 hearts were arrested with Bretschneider cardioplegia (8 degrees C) oxygenated with 98% oxygen (O2) and 2% carbon dioxide in comparison to 14 hearts receiving Bretschneider solution saturated with 98% nitrogen (N2) and 2% carbon dioxide as a control group for either 60 or 90 min (O(2)60, O(2)90, N(2)60, N(2)90 groups, n = 7). Seven hearts were used to determine preischemic baseline values of ATP, ADP and CP, 2 were excluded. The results showed a significantly poorer preservation of high-energy phosphates in hearts receiving oxygenated Bretschneider cardioplegia as compared to hearts receiving nitrogenated cardioplegia (p < 0.05). Postischemic recovery of hemodynamics did not demonstrate any statistically significant differences between the groups. However, the intragroup analysis showed a tendency towards weaker hemodynamic recovery in hearts treated with oxygenated cardioplegia. in contrast to the beneficial effect of oxygenated St. Thomas solution. In conclusion our findings suggest that oxygenated Bretschneider cardioplegia leads to significantly poorer preservation of high-energy phosphates and depressed hemodynamic recovery.