Introduction to Clinical Pharmacology Chapter 17 Anesthetic Drugs

Introduction to Anesthesia and Types of Anesthesia Induced by various drugs to bring about partial or complete loss of sensation Types of anesthesia: Local anesthesia Regional Anesthesia Spinal Anesthesia General anesthesia Anesthesiologist Trained physician to administer anesthesia

Local Anesthesia and Types #1 Topical anesthesia: application of the anesthesia to surface of skin, open area, mucous membrane Local infiltration anesthesia: injection of anesthesia into tissue Epinephrine might be used for vasoconstriction but not used on extremities Dental procedures, suturing of small wounds, making an incision into a small area

Local Anesthesia and Types #2 Local anesthesia (cont.): Regional anesthesia: injection of anesthesia around nerves to prevent sending pain signals Spinal anesthesia: injection of anesthesia into the subarachnoid space of the spinal cord-loss of sensation in lower abdomen and lower extremities Conduction blocks: injection of anesthesia into or near a nerve trunk include epidural and transsacral blocks

Preparing Patient for Local Anesthesia Take patient’s allergy history Explain how anesthetic will be given and how it works Prepare the area to be anesthetized: Cleaning the area with antiseptic, shaving the area Requires fasting May administer intravenous sedative

Administering Local Anesthesia Mixed with epinephrine to cause local vasoconstriction Be aware of when to and when not to use epinephrine Epinephrine contraindicated when used on an extremity

Nursing Responsibilities When Caring for Patient Receiving Local Anesthesia Applying dressing to the appropriate surgical area Observe area for bleeding, oozing, other problems after administration

Preanesthetic Drugs Given before administration of anesthesia May consist of one drug or a combination of drugs

Preanesthetic Drugs: Uses Used to decrease anxiety and apprehension immediately before surgery Used to decrease secretions of the upper respiratory tract Used to lessen the incidence of nausea and vomiting during the immediate postoperative recovery period

Selection of Preanesthetic Drugs May consist of one or more drugs Opioid agonists or barbiturate/antianxiety agents may be given to relax the patient-by depressing CNS Antiemetics given to prevent vomiting when coming out of sedation Cholinergic blocking drug such as atropine is given to dry secretions in the upper respiratory tract Drug diazepam (valium) used for preoperative sedation

Nursing Responsibilities #1 Assess the physical status of the client-check the chart for lab values to ensure provider is aware of any abnormal values Describe or explain the preparations for surgery ordered by the physician Describe or explain immediate postoperative care Demonstrate, describe, and explain postoperative patient activities Emphasize the importance of pain control using PCA pump and demonstrate use of pump

General Anesthesia The choice of anesthetic drug depends on: General physical condition of the patient Area, organ, system being operated on Anticipated length of surgical procedure

Drugs Used for General Anesthesia #1 Barbiturates and similar agents: Methohexital; etomidate; propofol Benzodiazepines: midazolam- a short-acting benzodiazepine CNS depressant, is used as a preanesthetic drug to relieve anxiety (not prevent vomiting); for induction of anesthesia; for conscious sedation before minor procedures, such as endoscopy; and to supplement nitrous oxide and oxygen for short surgical procedures Ketamine- rapid-acting general anesthetic ketamine will exhibit profound analgesia, cardiovascular stimulation, respiratory stimulation, and enhanced skeletal muscle tone Gases and volatile liquids: Nitrous oxide; sevoflurane (Ultane); isoflurane (Forane); desflurane (Suprane)

Drugs used for General Anesthesia #2 Opioids Analgesic fentanyl; droperidol; remifentanil; neuroleptic drug Skeletal muscle relaxants-help produce relaxation of skeletal muscles during certain types of surgeries involving the chest or abdomen and are used to facilitate the insertion of an endotracheal tube Anectine; Nimbex

Stages of General Anesthesia Stage I: Analgesia; Anesthesia Stage II: Delirium and excitement Stage III: Surgical analgesia Stage IV: Respiratory paralysis

Nursing Responsibilities #2 Preanesthesia Performing the required tasks and procedures as prescribed Checking the chart for any recent, abnormal laboratory tests Placing a list of known or suspected drug allergies Administering the preanesthetic drug

Nursing Responsibilities #3 Postanesthesia Admitting the patient to the unit according to hospital procedure or policy Positioning the patient to prevent aspiration of vomitus and secretions Checking the airway for patency, assessing the respiratory status, respiratory tract for irritation, and giving oxygen as needed

Nursing Responsibilities #4 Postanesthesia (cont.) Check blood pressure and pulse, IV lines, catheters, drainage tubes, surgical dressings, and casts Review the patient’s surgical and anesthesia records Monitor the blood pressure, pulse, and respiratory rate every 5 to 15 minutes until the patient is discharged from the area

Nursing Responsibilities #5 Postanesthesia (cont.) Check the patient every 5 to 15 minutes for emergence from anesthesia. Suctioning is provided as needed Exercise caution in administering opioids Discharge the patient from the area to his or her room or other specified area

Question #1 Is the following statement true or false? Anesthesia is the loss of feeling or sensation.

Answer to Question #1 True Anesthesia is the loss of feeling or sensation. Local and general anesthesia are provided for pain relief and to perform otherwise painful procedures.

Question #2 Is the following statement true or false? General anesthesia includes topical, local infiltration, and regional pain relief and is used when dealing with a specific area of the body and the patient can remain conscious.

Answer to Question #2 False Local anesthesia includes topical, local infiltration, and regional pain relief and is used when dealing with a specific area of the body and the patient can remain conscious. General anesthesia requires multiple drugs and stages to achieve a state where surgical procedures can be performed without pain, movement, or memory.

Question #3 Is the following statement true or false? Nursing responsibilities include tasks to assist, maintain, and recover a patient who has been given an anesthetic.

Answer to Question #3 True Nursing responsibilities includes tasks to assist, maintain, and recover a patient who has been given an anesthetic.