General issues on premedication

Abstract

Premedication refers to a drug treatment given to a patient before a medical procedure (surgical or invasive). Some groups of pharmacological substances are used as premedication: 1. hypnotics (barbiturates, benzodiazepines) 2. psychotropic remedies (tranquilizers - benzodiazepine group, neuroleptics - phenotiazine and butirofenone derivates) 3. antihistamines remedies 4. opioid analgesics 5. colinoblocantes remedies. 1. a) Barbiturates are used as premedication before the night of surgery in combination with tranquilizers, to accelerate and improve their sedative and hypnotic effect. Phenobarbital and etaminal - sodium are long - acting barbiturates, which assures a quiet sleep throughout the night, b) Benzodiazepines: nozepam, diazepam. On the on the evening before the operation the patient is given hypnotic barbiturates in combination with or without association (10 - 15 mg) 30 minutes before sleep. This provides calmness uptown sleep, but without combination with barbiturates hypnotics do not guarantee sleep till morning. 2. Tranquillizers - benzodiazepine: diazepam, fenazepam. An important condition for an anti - stress effect is the administration of tranquillizers in the evening before the operation, and then 2 times in the morning: immediately after wakining up (6 - 7 о clock) and 40 - 45 minutes before general anesthesia. Neuroleptics provide antipsychotic effects compared with tranquilizers, which give only psihosedativ effect. Phenothiazines. One of the strongest representatives of the derivatives of phenothiazine is chlorpromazine, which is used less in premedication due to the danger of adrenolytic effect of arterial hypotension.Taps butyrophenone in premedication is used less than diazepam, because, it causes emotional distress, anxiety, irritability. 3. Antihistamine remedies. As histamine HI - receptor blockers are used: diphenhidamine (dimedrole), cloropiramine (suprastine). This medicine is given with other remedies premedicated about 30 - 40 minutes before general anesthesia, especially to patients predisposed to allergies. Histamine H2 - receptor blokers such as ranitidine or cimetidine may be used in order to reduce secretion of glands before general anesthesia to avoid Mendelson syndrome. 4. Opioid analgesics Morphine and its analogues are used only in cases of pain. Administration of these medicines is allowed only with tranquilizers. 5. Cholinoblocant remedies Atropine is the classic representative m - colinolitics. It is used in: any type and intraoperative bradicardia; before anesthesia with diethyl ether, halothane; with the neostigmine in decurarisation. Conclusion: Tranquilizers are the most important element in premedication. The other elements of premedication do not assure by themselves an effective psycho - emotional inhibition. They can be used as adjuvants of premedication to obtain special effects.