Local & General Anesthetics Ch 11

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

Main Categories Inhaled – may be liquid or gas Nitrous oxide – gas Halothane – liquid Several 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 Fentanyl Opioid analgesic – pain relief Versed Benzodiazepine - amnesia Atropine Anticholinergic – decreases secretions Demerol, morphine Opioid analgesics – lighter pain relief Vistaril, phenergan, seconal Sedative/hypnotic – lighter amnesia/sedation

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

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

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

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

CNS Depressants & Muscle Relaxants Ch 12

Sedatives Reduce nervousness Reduce excitability Reduce irritability Do Not cause sleepiness

Hypnotics Reduce nervousness Reduce excitability Reduce irritability Do cause sleep

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

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

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

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

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

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

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

Antiepileptic Agents Ch 13

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

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