Local General Anesthetics General Anesthesia Alters responses of

Local & General Anesthetics

General Anesthesia Alters responses of the Central Nervous system n Causes one or more of the following n Pain relief n Muscle relaxation n Relaxation of reflexes n Deep sleep n n Commonly used during surgery

Main Categories n Inhaled – may be liquid or gas Nitrous oxide – gas n Halothane – liquid n n Several n others that end with –ane Inhaled drugs are used together with IV drugs to provide the best level of sedation for the patient & procedure = Balanced Anesthesia

Intravenous n Fentanyl n n Versed n n Anticholinergic – decreases secretions Demerol, morphine n n Benzodiazepine - amnesia Atropine n n Opioid analgesic – pain relief Opioid analgesics – lighter pain relief Vistaril, phenergan, seconal n Sedative/hypnotic – lighter amnesia/sedation

Local Anesthetics n AKA Regional anesthetics Block nerve conduction in specific area of body n Prevents pain sensation n n 2 Forms Topical n Parenteral (injected) n

Topical n May be patch, cream or lotion, liquid, spray Dermoplast n Lidocaine n Pontocaine n EMLA cream n

Parenteral n Spinal n n Into the space surrounding the spinal cord Epidural Through catheter into the epidural space just outside the spinal cord n May remain in place for continuous infusion n Infiltration – to numb area to be sutured n Nerve block – stop impulses from specific nerve (example: chronic back pain) n

Neuromuscular Blockers Used during surgery n Paralyze respiratory and skeletal muscles n Requires artificial ventilation n Also used in ICU with ventilator patients n

CNS Depressants & Muscle Relaxants Ch 12

Sedatives Reduce nervousness n Reduce excitability n Reduce irritability n Do Not cause sleepiness n

Hypnotics Reduce nervousness n Reduce excitability n Reduce irritability n Do cause sleep n

Sedative-Hypnotics Drugs that can have either sedative or hypnotic effect n 3 classifications n Barbiturates n Benzodiazepines n Miscellaneous agents n

Barbiturates Are Habit-forming (addictive) n Rapidly lead to toxicity n Depress respirations n Used for n Anesthesia n Control convulsive conditions n Prevent epileptic seizures n

Barbiturates, cont’d n Phenobarbital n n Most commonly prescribed Forms Tablets n Capsules n Elixirs n Injections n Suppositories n

Benzodiapines Relatively safe n Most commonly prescribed n Used for n Sedation n Sleep induction n Skeletal muscle relaxation n Reduce anxiety n

Benzodiazapines, cont’d n Examples Temazepam = restoril n Zolpidem = ambien n n Antidote is flumazenil = romazicon

Muscle Relaxants Act on the CNS n Benefit is more from sedation than from relaxation of muscles n Primarily used for relief of muscle spasms n n n Best when used with physical therapy No specific antidote

Miscellaneous agents n Chloral hydrate = Noctec Oldest in this category n Relatively short duration of action n Does not suppress REM sleep n n Tizanidine = zanaflex n Treats muscle spasms

Antiepileptic Agents Ch 13

Epilepsy Common name for seizure disorder n Not a disease n CNS dysfunction n Momentary lapses to total body convulsions Action not completely known n Alter electrolytes

Treatment Diazepam = valium to stop seizure once it has started Phenytoin = dilantin to prevent future seizure activity