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T Luoma

Publications and source records attributed to T Luoma.

4 recordsLinked to original sources
PubMed1994

A prospective randomized comparison of the accuracy of computer-assisted versus GUSTO nomogram--directed heparin therapy.

Failure to adequately anticoagulate the blood of patients receiving recombinant tissue plasminogen activator (TPA) leads to greater rates of rethrombosis. In a multicentered, randomized trial in 51 patients we compared the ability to achieve and maintain therapeutic anticoagulation by use of computer-assisted heparin therapy or the GUSTO (Global Utilization of Streptokinase and TPA for Occluded Coronary Arteries) heparin nomogram guidelines in patients with myocardial infarction treated with recombinant TPA. Heparin therapy was initiated with either computer-generated starting doses or GUSTO guideline starting doses. Activated partial thromboplastin times were measured every 6 to 8 hours for the first 24 hours. The therapeutic range used in this trial was 1.5 to 2.5 times the patient's baseline activated partial thromboplastin time (APTT). Ninety-four percent of the APTT ratios in the computer group were equal to or greater than 1.5 in the first 24 hours compared with 78% in the GUSTO group (p < 0.009). No significant difference in bleeding was found (7.7% for GUSTO; 4.2% for computer). Incremental time-dependent changes in heparin dose were found (day 1, 1110 +/- 243 units/hr, APTT ratio = 2.5 +/- 1.4; day 3, 1380 +/- 374 units/hr, APTT ratio, 1.9 +/- 0.4). Computer-assisted heparin therapy TPA results in superior anticoagulation accuracy compared with the GUSTO guidelines. In addition, the pharmacodynamic response to heparin changes in the 2 to 3 days after administration of TPA, leading to greater heparin requirements.

Aged↗
PubMed1991

Inhibition of human and rabbit platelet aggregation by chlorophenoxyacid herbicides.

Inhibition of human platelet aggregation by eight chlorophenoxyacid herbicides was studied in vitro. Thrombocyte aggregation in the platelet-rich plasma was induced by 1.0-32.0 microM adenosine diphosphate (ADP), 0.32-32.0 microM adrenaline or 7.5-30.0 micrograms/ml collagen with and without chlorophenoxyacid (0.05-2.0 mg/ml). Platelet aggregation by each inducer was inhibited dose dependently by all the eight chlorophenoxyacids at concentrations between 0.1 and 2.0 mg/ml. Increasing the concentrations of ADP and collagen but not of adrenaline inhibited the antiaggregatory action of chlorophenoxy-acids. No essential differences in inhibitory effect were found between different chlorophenoxyacids varying in respect of their ring substituents and the length of the carboxylic side chain. In the platelet-rich plasma prepared from rabbits 2.5 h after subcutaneous injection of 2.4-dichlorophenoxyacetic acid or 4-chloro-2-methylphenoxyacetic acid (100-150 mg/kg), platelet aggregation by ADP was inhibited 20-30%, compared to plasma taken from the rabbits before the chlorophenoxyacid treatment. The inhibition had disappeared by 20-23 h after administration. The results indicate that chlorophenoxyacid herbicides inhibit human platelet aggregation. Furthermore, the inhibition is probably involved in haemorrhages known to occur in various tissues of animals intoxicated by chlorophenoxyacid herbicides.

2,4,5-Trichlorophenoxyacetic Acid↗