Chapter 19: Drugs for Local and General Anesthesia

Question 1

Compare and contrast the five major clinical techniques for administering local anesthetics

Answer 1

• Topical (surface) anesthesia
  
  • Creams, sprays, suppositories, drops, and lozenges
  • Applied to mucous membranes including the eyes, lips, gums, nasal membranes, and throat
• Infiltration (field block) anesthesia
  
  • Direct injection into tissue immediate to the surgical site
  • Drug diffuses into tissue to block a specific group of nerves in a snall area close tot he surgical site
• Nerve block aesthesia
  
  • Direct injection into tissue that may be distant from the operation site
  • Drug affects nerve bundles serving the surgical area; used to block sensation in a limb or large area of the face
• Spinal anesthesia
  
  • Injection into the cerebral spinal fluid (CSF)
  • Drug affects a large, regional area, such as the lower abdomen and legs
• Epidural anesthesia
  
  • Injection into the epidural space of the spinal cord
  • Most commonly used in obstetrics during labor and delivery

Question 2

Identify the four stages of general anesthesia

Answer 2

1. Loss of pain: the patient loses general sensation but may be awake This stage proceeds until the patient loses consciousness 2. Excitement and hyperactivity: the patient may be delirious and try to resist treatment. Heart rate and breathing may become irregular and blood pressure can increase. IV agents are administered here to help calm the patient. 3. Surgical anesthesia: skeletal muscles become paralyzed. Cardiovascular and breathing activities stabilize. Eye movements slow and the patient becomes still. 4. Paralysis of the medulla region in the brain (responsible for controlling respiratory and cardiovascular activity): if breathing or the heart stops, death could result. This stage is usually avoided during general anesthesia.

Question 3

Describe the differences between two major chemcial classes of local anesthetics

Answer 3

• Esters: first anesthetic to be used in medical procedures
  
  • General adverse effects: CNS depression; burning, stinging, and redness at topical application sites; respiratory arrest, circulatory failure, anaphylaxis
  • Examples:
    
    • Benzocaine (Americaine, Anbesol, Solarcaine)
    • Procaine (Novocaine)
    • Proparacaine (Alcaine)
    • Tetracaine (Pontocaine)
• Amides: largely replaced esters because they produce fewer side ffects and generally hae a larger duration of action
  
  • General adverse effects: burning, stinging, and redness at topical application sites; difficulty breathing or swallowing, respiratory depression and arrest, convulsions, anaphylaxis, burning, contact dermatitis

Question 4

Explain why epinephrine and sodium bicarbonate are sometimes included in local anesthetic cartridges

Answer 4

Constricts blood vessels in the immediate area to help keep anesthetics localized to extend the duration of action - keeps anesthetics in that area longer

Question 5

Identify the actions of general anesthetics on the central nervous system

Answer 5

General anesthetics depress most nervous activity in the brain

• Loss of consciousness
• Loss of memory
• Loss of body movement

Question 6

Compare and contrast the two primary ways that general anesthesia may be induced.

Answer 6

Can be induced through IV drugs and inhaled drugs.

IV drugs act within a few seconds while inhaled drugs tend to take a little longer.

IV drugs are used initially and then inhaled drugs are used to maintian sedation.

Using IV drugs first allows the dose of inhaled drugs to be lower.

When combined, produce greater analgesic effect.

Question 7

Give an example of esters, their mechanism of action, primary actions, and important adverse effects.

Answer 7

• Examples:
• MOA:
• Primary Actions:
• Adverse Effects:

Question 8

Give an example of amides, their mechanism of action, primary actions, and important adverse effects.

Answer 8

• Examples
• MOA
• Primary actions
• Adverse effects

Question 9

Give an example of IV general anestheics, their mechanism of action, primary actions, and important adverse effects.

Answer 9

• Examples:
• MOA:
• Primary Actions:
• Adverse Effects:

Question 10

Give an example of Inhaled Drugs, their mechanism of action, primary actions, and important adverse effects.

Answer 10

• Therapeutic Gas
  
  • Examples:
  • MOA:
  • Primary Actions:
  • Adverse Effects:
• Volatile Liquids:
  
  • Examples:
  • MOA:
  • Primary Actions:
  • Adverse Effects:

Question 11

Give an example of neuromuscular-blockers, their mechanism of action, primary actions, and important adverse effects.

Answer 11

• Examples:
• MOA:
• Primary actions:
• Adverse effects:

Question 12

Categorize drugs used before, during, and after anesthesia based on their classification and drug action

Answer 12

• d

Question 13

Use the nursing process to care for patients who are receiving pharmacotherapy with anesthetic agents.

Answer 13

• Baseline assessment prior to administration
  
  • Obtain complete health history inlcuding allergies and pertinent labs if available
  • Obtain baseline vitals and weight
  • Assess patient and area if local anesthetic
• Assessment throughout administration
  
  • Assess for desired effects
  • Monitor vital signs
  • Assess level of consciousness
  • Monitor any adverse effects

Question 14

The patient received lidocaine viscous before a gastroscopy was performed. Which event would be a priority for a nurse to assess during the postprocedual period?

a. Return of gag reflex
b. Ability to urinate
c. Leg pain
d. Ability to stand

Answer 14

a. Return of gag reflex

The patient’s throat was anesthetized during gastroscopy with lidocaine viscous. The patient should be assessed for the return of gag reflex before being allowed to drink or eat to prevent aspiration.

Leg pain, abilty to stand, and ability to urinate are not assessments related to the procedure or the lidocaine viscous use. If these are noted as abnormal, other causes should be investigated.

Question 15

A young patient requires suturing of a laceration to the right forearm, and the provider will use lidocaine (Xylocaine) with epinephrine as the local anesthetic prior to the procedure. Why is epinephrine inlcuded in the lidocaine for this patient?

a. It will increase vasodilation at the site of laceration
b. It will prevent hypotension
c. It will ensure that infection risk is minimized post-suturing
d. It will prolong anestehtic action at the site.

Answer 15

d. It will prolong anestehtic action at the site.

Solutions of lidocaine containing epinephrine are used for local anesthesia because the epinephrine will prolong the anesthetic action at the site. Because this is a young patient, that may be particularly advantageous.

Epinephrine causes vasoconstriction and HTN when given systemically; this drug is being used locally.

Epinephrine will not prevent post suturing infection and the site should continue to be monitored.

Question 16

The patient, who is scheduled to have a minor in-office surgical procedure, will recieve nitrous oxide and expressed concern to the nurse that the procedure will hurt. Which would the nurse’s best response?

a. “You may feel pain during the procedure, but you won’t remember any of it.”
b. “You will be unconscious the entire time and won’t feel any pain.”
c. “You will not feel any pain during this procedure because the drug blocks the pain signals.”
d. “You will feel pain, but you won’t preceive it the same way; that’s why it is called ‘laughing gas.’”

Answer 16

c. “You will not feel any pain during this procedure because the drug blocks the pain signals.”

Nitrous oxide suppresses the pain mechanisms within the CNS, thereby causing analgesia.

Nitrous oxide does not produce complete loss of consciousness or the profound relaxation of skeletal muscles as general anesthetics do and the patient does not perceive pain differently; pain is suppressed.

Question 17

During administration of nitrous oxide, the patient develops anxiety, excitement, and combativeness. The nurse would anticipate that what change in the patient’s anesthesia is needed?

a. The nitrous dose will be increased
b. Propofol (Diprivan) will be given along with the nitrous oxide
c. Succinylcholine (Anectine) will be given to the patient
d. The nitrous oxide dose will be decreased.

Answer 17

d. The nitrous oxide dose will be decreased.

Anxiety, excitement, and combativeness are signs that the dose of nitrous oxide is high and the patient is exhibiting signs of the second stage of anesthesia. Lowering the dose may reduce these symptoms.

Propofol would cause additional CNS depression and is not advised.

Succinylcholine is a neuromuscular blocking dug that will increase the risk of significant resporatory adverse effects due to its muscle-paralyzing actions.

Question 18

A patient is admitted to the postanesthesia recovery unit (PACU) after receiving ketamine (Ketalar) after his minor orthopedic surgery. What is the most appropriate nursing action in the recovery period for this patient?

a. Frequently orient the patient to time, place, and person.
b. Keep the patient in a bright environment so there is less drowsiness.
c. Frequently assess the patient for sensory deprivation
d. Place the patient in a quiet area of the unit with low lights and away from excessive noise

Answer 18

d. Place the patient in a quiet area of the unit with low lights and away from excessive noise

Neuroleptanalgesia drugs such as katamine do not result in full loss of consciousness but cause disconnection from events that are occurring. Confusion, anxiety, fear, or panic may occur in the immediate posprocedure period if snesory stimulation is misinterpreted. Sensory stimulation should be kept to a minimum during this period for this reason.

Frequent orientations and assessments, above those required for patient safety or monitoring, increase sensory stimulation and may result in extreme reactions by the patient.

A bright environment increases sensory stimulation.

Question 19

A patient has received succinylcholine (Anectine, Quelicin) along with the general anesthetic in surgery. Which abnormal finding in the recovery period should be reported immediately to the provider?

a. Temperature 38.9C (102F)
b. Heart rate 56
c. Blood pressure 92/58
d. Respiratory rate 15

Answer 19

a. Temperature 38.9C (102F)

The combination of succinycholine (Anectine, Quelicin) and general anesthetics is known to trigger malignant hyperthermia in some patients. A temperature of 38.9C (102F) may signal the development of malignant hyperthermia and should be immediately reported.

General anesthetics derpress CNS function, and bradycardia, bradypnea, and lowered pressure or hypotension are not uncommon findings in the immediate postoperative period. The nurse should compare these findings with the baseline assessment to determine if they are abnormal or a normal expected effect of the general anesthesia.

Question 20

Rob Valetti is a 28-year-old steelworker for a heating and cooling company. While on the job, he cut his right hand with a piece of steel for an air-conditioning vent. He is admitted to the emergency department for sutures to the right middle and ring fingers, and palm. The laceration will be anesthetized with lidocaine prior to suturing.

What is the action of licocaine?

Answer 20

Lidocaine blocks the conduction of electrical impulses by reducing the sodium permeability at the cellular level. This prevents pain transmission to the CNS.

Question 21

Rob Valetti is a 28-year-old steelworker for a heating and cooling company. While on the job, he cut his right hand with a piece of steel for an air-conditioning vent. He is admitted to the emergency department for sutures to the right middle and ring fingers, and palm. The laceration will be anesthetized with lidocaine prior to suturing.

Why do some solutions of lidocaine containe epinephrine?

Answer 21

Epinephrine added to lidocaine (Xylocaine) incresaes the local anesthetic action from about 20 minutes to as long as 60 minutes. The vasoconstriction caused by the epinephrine will also decrease bleeding and allow for better visualization of the area.

Question 22

Rob Valetti is a 28-year-old steelworker for a heating and cooling company. While on the job, he cut his right hand with a piece of steel for an air-conditioning vent. He is admitted to the emergency department for sutures to the right middle and ring fingers, and palm. The laceration will be anesthetized with lidocaine prior to suturing.

As the nurse, what postoperative instructions will you give rob?

Answer 22

Postprocedure, Rob should be taught that the area may remain numb for some time and he should take precautions to avoid injury to the area. The area around the suture line may appear blanced, which is normal and related to the epinephrine that was used. He should continue to observe the area for any redness, swelling, warmth, or other signs of infection, and return to the provider as directed for suture removal.

Question 23

A patient, age 77, is scheduled for an open reduction with internal fixation of the right hip for a fracture. When preparing the postoperative care plan, what should be included for this patient in the immediate postoperative recovery period?

Answer 23

In the postoperative period, the nurse will ensure that vital signs are taken frequently and that any abnormal findings are reported to the healthcare provider. If the patient received succinylcholine (Anectine, Quelicin) with the general anesthetic, the nurse will also frequently monitor temperature for signs of malignant hyperthermia. The patient should be reoriented to his surroundings until full consciousness returns, and safety measures such as convenient call light and frequent visual checks should be initiated. Any signs of confusion, disorientation, or other cognitive impariment should be reported to the provider. The nurse should ensure return of the patient’s gag reflex and ability to swallow before allowing the patient to eat or drink.

Question 24

A patient who has a history of cardiac dysrhythmias returns from surgey during which the patient received isoflurane (Forane) as a general anesthetic. What adverse effect of isoflurane might occur related to this patient’s past medical history? What priority assessment data will the nurse gather in the recovery peroid related to this?

Answer 24

Because of the patient’s prior history of dysrhythmias, this may result in life-threatening cardiac dysrhythmias. The nurse should frequently monitor the patient’s ECG, blood pressure, and pulse rate and volume during the recovery period. Adrenergic drugs, phenothiazines, and other specific medications will have to be avoided after surgery unless necessary, or drugs will have to be monitored due to the possibility of dysrhythmias.