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The main therapeutic objective of emergency after acute myocardial infarction (MI) is limiting the infarcted area through the opening of occluded artery, decreasing demand of myocardial oxygen and preventing MI complications.When arterial wall is injured, the collagen tissue is exposed to platelet aggregation that leads to releasing adenosine 5 diphosphate and subsequent to it, platelet adhesion and formation of fibrin is occured. After a while fibrin activates directly the fibrinolytic system, then plasminogen activator is infused and it changes plasminogen into plasmin so that it makes fibrin to be digested.TPA is one of the most effective thromboclastic drugs. It is an enzyme that is produced through recombinant DNA. TPA is a type of fibrin that is infused in circulatory system and binds to fibrin in a thrombus and it converts the plasminogen to plasmin. It is prescribed for adults presenting the early signs of acute myocardial infarction.The recommended dose of TPA for the adults weighing more then 65 Kg is 100 mg. If the patient weighs less than 65 Kg, dosage is determined by a formula as the following: 1.25 mg TPA per Kg body weight.The primary period of prescribing TPA in patients suffering from MI is at the time of transferring them to the hospital or emergency ward. More over, treatment is carried on with effective dose of TPA for 3 hours.The fundamental nursing procedures for the patients receiving TPA consist of complete assessing the patient and obtaining basic information and history of the patient's health and disease.During the infusion of TPA, the patient's bleeding should be continually checked. The recovery signs after TPA infusion is indicated as dysrhythmia, due to reperfusion and it should not be taken into consideration as a negative sign. Some other recovery signs are relieving chest pain and reversing ST segment

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Background & Aim: Hemodialysis centers are highly susceptible to nasocomial infections due to application of hemodialysis machines, medical equipment, and invasive techniques and devices. This research was carried out in order to evaluate methods of infection control using by staff of hemodialysis centers.

Methods & Materials: In this descriptive study, all hemodialysis units in hospitals of Tehran University of Medical Sciences (n=4) were studied. Data were gathered using a 3-section questionnaire as well as five series of check-lists that were designed to evaluate physical characteristics of the units, methods of disinfection processes of the units, hemodialysis machines, and common equipment, and finally precaution measurements using by the staff. Data were described using SPSS statistical software.

Results: Research findings showed that just one of the study units was appropriate regarding physical characteristics of the units. Method of disinfection of hemodialysis centers was appropriate in 50 per cent of the study units and it was relatively appropriate in the rest. Disinfection of hemodialysis machines was appropriate in all units. Regarding disinfection of the shared equipment, all units were relatively appropriate. In 25 per cent of the units, staff had relatively appropriate precaution measurements and the rest (75 per cent) had inappropriate measurements.

Conclusion: Results showed that the methods of infection control using by the staff of hemodialysis centers in hospitals of Tehran University of Medical Sciences were not appropriate.