Biomedical subjects
L Kaspar
Publications and source records attributed to L Kaspar.
[Biguanide-induced and - associated lactic acidosis: serum and tissue biguanide levels in hyperlactaemia and lactic acidosis (author's transl)].
An investigation was carried out on 30 diabetic patients in an attempt to clarify the relationship between serum biguanide levels and raised lactate. No consistent relationship was demonstrable between the serum biguanide level, administered dosage and time of administration. There was also no correlation between biguanide and lactate increase. It is not justifiable to quote a specific serum level of biguanides in defining lactic acidosis. A causal association between biguanide medication and lactic acidosis seems to be possible only by determination of serum and tissue levels. Determination of biguanide levels was carried out in the serum and tissue of a patient who had died as a result of lactic acidosis after phenformin administration. While the serum levels were only slightly higher than the therapeutic range, both liver and kidney tissue showed highly toxic levels. Furthermore, the amount of biguanides in the body was calculated in another patient successfully treated for lactic acidosis after buformin therapy. A differentiation should be made between biguanide-induced and biguanide-associated lactic acidosis. In both forms serum levels can be within relatively low ranges. In the former condition, the biguanides alone are responsible for the development of lactic acidosis by blocking the respiratory chain. In the latter condition they aggravate an already existing pathological condition, and can, therefore, represent a lethal factor.
Preprogrammed insulin infusion with a portable pump system.
A glucose-controlled insulin infusion system (Biostator) was used to determine patient insulin requirement for clinical evaluation of a portable pump system (technical development by Siemens AG). Results from 6 insulin-dependent diabetics with respect to quality of control, carbohydrate/insulin ratio, and insulin requirement are shown. Preprogrammed insulin infusion with the portable system was carried out for up to 117 days.
Use of glucose-controlled insulin infusion system for improvement of subcutaneous insulin regimen.
The use of an artificial pancreas for blood glucose monitoring and feedback correction for evaluation and improvement of subcutaneous insulin therapy facilitates the process of finding an optimal therapy regime for the individual patient. The frequency of hypoglycemic episodes can be reduced while maintaining good control, and hospital stays can be considerably shortened. This procedure is particularly useful in achieving tight control in pregnant diabetics.
Treament of biguanide-induced lactic acidosis with dichloroacetate. 3 case histories.
The administration of dichloroacetate (DCA) in cases of biguanide-induced lactic acidosis (LA) improves pyruvate oxidation and therefore increases energy production from glucose. Preliminary results of treatment of LA in humans are reported. A continuous fall in pyruvate was observed in all 3 cases after administration of at least 20 g of DCA (4 g i.v. bolus, then continuously 12 g/h). In Case 1, in which no supplementary measures for controlling the acidosis were applied, the acidosis did not improve and the patient died. In Case 2, despite administration of tris-buffer and dialysis, pH-values could not be raised sufficiently. The production of hydrogen ions persisted and lactate continued to rise. This patient also died. Case 3 was admitted in the beginning stages of a phenformin-induced LA, and in this case therapy was successful. The decline in pyruvate was accompanied by a slow fall in lactate, and a further fall in pH was averted. The clinical condition of the patient improved markedly after i.v. administration of a total of 34 g of DCA.
[Diabetic control with a portable insulin infusion pump for 7 weeks (author's transl)].
A portable insulin infusion pump was used to achieve diabetic control over a period of 7 weeks in a juvenile onset-type diabetic. Insulin was infused at a basal rate and further doses could be triggered externally by the patient. Insulin requirement had been previously determined by means of an artifical beta-cell (Glucose Controlled Insulin Infusion System). This method of insulin administration resulted in a clear improvement in diabetic control. Some problems did arise in connection with materials from which the instrument and catheter were constructed. However, it was shown that a portable insulin pump can be used with out-clinic patients for a number of weeks and is also justified for at least certain cases.
[Four cases of fatal lactic acidosis during biguanide therapy (author's transl)].
Four case reports of lactic acidosis occurring during biguanide treatment (2 with phenormin, 2 with buformin) are analysed. Three of the patients died in a toxic state of lactic acidosis, whilst the fourth patient survived lactic acidosis, but died 11 days later due to myocardial infarction. In spite of serum biguanide levels within the therapeutic range, one patient had highly toxic hepatic levels of phenformin (13,500 ng/g tissue). Two factors are essential for the treatment of lactic acidosis: 1. rapid diagnosis: history of biguanide intake; clinical symptoms; acid-base imbalance; rapid lactate determination to establish the diagnosis. 2. therapy: correction of acidosis, insulin and glucose; shock treatment; forced diuresis and/or haemodialysis. From the high numbers of biguanide-treated diabetics and the incidence of lactic acidosis in other countries it can be assumed that this toxic side effect of biguanide treatment occurs relatively frequently in Austria too, but remains largely undetected.
[Hyperosmolar diabetic coma--osmolality and urea].
Explore the source record for details and available documents.
[No free water in the treatment of "hyperosmolar diabetic coma": treatment control by comparing serum and CSF (author's transl)].
Some serum and CSF concentrations were measured in five patients with severe hyperosmolar coma (mean blood sugar = 58.9 mmol/l; osmolarity = 406 mosmol/l). A gradual decrease of serum osmolarity prevented the development of an osmotic gradient between CSF and extracellular space. Insulin treatment (1-20 IU/h) with a motor infusion pump and infusion of hypertonic solutions decreased serum osmolarity by 2-4 mosmol/l X h. The faster fall of glucose in the extracellular space was compensated by hypertonic saline infusions (up to 365 mosmol/l). All patients survived.
Dichloracetate in biguanide-induced lacticacidosis.
Explore the source record for details and available documents.