general and local anesthetics

what is anesthesia

a state of reduced neurologic function; can range from drowsiness (mild) to total loss of consciousness and reflexes

types of anesthesia

• General 

• Moderate sedation 

• Local

• Neuromuscular blocks 

general nursing interventions for anesthetics

• Review the patient’s medical and surgical history

• Assess medications, alcohol, and drug use

• Baseline lab work and EKGs

• Surgical and anesthesia plan

• Preop teach about Turn, cough, deep breath in post op period

general anesthetics key fx

• Drugs to eliminate feeling pain/sensation during medical procedures through central and peripheral nervous system

• Patient loses consciousness - completely unaware of surroundings with loss of stimuli

• Reserved for major or invasive surgeries

• Rapid onset and quickly metabolized

are protective reflexes lost with general anesthetics?

yes

Patient loses protective reflexes (gag, blink, respiratory muscles -> paralysis) -> mechanical ventilation required

who are general anesthetics administered by

• ADMINISTERED BY: ANESTHESIOLOGIST, CRNA, ANESTHESIA ASSISTANT

types of general anesthetics

• Inhalation - Liquids or gases that are vaporized in oxygen and inhaled

• Parenteral - Administered IV

• Adjunct - Medications given along with anesthetics to enhance effects

what is overton-meyer theory

• Explains why some anesthetics are stronger than others

• Varies according to drug

what are classic stages of anesthesia

1. Analgesia/Amnesia: They’re awake but getting sleepy; pain relief and memory loss start.

2. Excitement/Delirium: They lose consciousness and may move or breathe irregularly for a moment.

3. Surgical Anesthesia: This is the goal. They’re fully unconscious, relaxed, and can be safely operated on.

4. Medullary Depression: Too deep. Breathing and heart function drop; life-threatening without immediate cardiac and respiratory support.

nursing interventions for general anesthetics

• Verify that anesthesia machine, suction, and emergency drugs (dantrolene) are available before induction

• Monitor patent IV access

• Monitor v/s, ECG, oxygen, and temp continuously

• Monitor for malignant hyperthermia

• During recovery, position patient on side to maintain airway and reduce aspiration risk

• Provide frequent orientation as patient emerges

• Evaluate for pain, nausea, and shivering (common s/e)

• Administer antibiotics as prescribed

patient teaching general anesthetics

• May experience drowsiness, sore throat, or mild nausea after anesthesia

• Deep breathing, coughing, and early ambulation to prevent complications (DVT or pneumonia)

• Do not drive or make major decisions 24 hours after

contraindications for general anesthetics 

• Allergy

• Depending on drug type

  • pregnancy

  • narrow-angle glaucoma

  • Acute porphyria

  • Know history of malignant hyperthermia

adverse effects of general anesthetics

• malignant hyperthermia

• toxicity or OD

malignant hyperthermia key fx

• Can occur during or after use of inhaled anesthetics or succinylcholine

• genetic life threatening reaction that causes a sudden spike in body temperature, along with muscle rigidity, tachypnea, and tachycardia

• the skeletal muscles go into a hypermetabolic state, producing excessive heat and lactic acid -> can quickly lead to acidosis and organ failure if not treated promptly

nursing interventions for malignant hyperthermia
complications?

• Recognize early signs (unexpected rise in ETCO2, tachycardia, muscle rigidity)

• stop anesthetic immediately, notify provider, administer dantrolene IV, initiate rapid cooling using cooling fluids, blankets

• monitor for complications (arrhythmias and electrolyte imbalances)

• document and notify family

toxicity/OD of general anesthetics key fx

• The ultimate cause of death with OD is usually cardiac or respiratory arrest

• if arrest occurs, initiate basic life support and oxygenation

general anesthetics drug interactions

• Antihypertensives - Cause HOTN

• Beta blockers - Can increase risk of bradycardia and myocardial depression

• Alcohol and CNS depressants - Additive sedative effects

general anesthetic drug examples

• Dexmedetomidine (Precedex)

• ketamine

• nitrous oxide

• propofol

• sevoflurane

dexmedetomidine key fx

• General anesthetic

• Procedural sedation

• Provides dose dependent sedation, anxiety reduction, and pain relief without significantly depressing respiratory system

• Often used for short, surgical procedures 

• Also used in ICU for sedation of mechanically ventilated patients

dexmedetomidine s/e

• bradycardia

• HOTN

dexmedetomidine nursing interventions

• Monitor for bradycardia and HOTN

• Assess level of sedation frequently and titrate per protocol

ketamine key fx

• General anesthetic

• IV, IM, SUBQ

• Produces a dissociative effect → patient appears awake but is unaware of surroundings

• Rapid onset and causes minimal depression to CV and RR function → useful in emergency or trauma settings

ketamine s/e

• Can cause hallucinations, nightmares, or vivid dreams

ketamine nursing interventions

• Provide calm and quiet environment

• Frequently orient patient as they wake up

• Continuously monitor airway and oxygen

nitrous oxide key fx

• AKA laughing gas

• Weakest general anesthetic 

• Inhaled

• Often used as dental agent or adjunct to more potent agents

nitrous oxide nursing interventions

• Monitor for n/v or dizziness post procedure

• Use in well ventilated area since the gas can linger and cause exposure

propofol key fx

• Parenteral anesthetic - Used for both induction and maintenance

• Used in ICU 

• Monitor triglycerides if used with TPN and long-term infusions

propofol nursing interventions

• Use strict aseptic technique, since it supports bacterial growth

• Monitor RR, airway, and oxygenation

• Discontinue if patient shows signs of propofol infusion syndrome (bradycardia, metabolic acidosis, cardiac failure)

sevoflurane key fx

• General anesthetic

• Widely used (esp. outpatient settings) because it is non-irritating to the airway

• Good for pediatric patients

nursing interventions for sevoflurane

• Monitor for post-op shivering or nausea

• Monitor for malignant hyperthermia

• Ensure adequate ventilation during emergence to remove residual gas

moderate sedation key fx

• AKA conscious or procedural sedation

• No complete loss of consciousness - Provides pain relief, anxiety reduction, and sometimes mild amnesia → memory loss

• Patient can maintain own airway and respond to commands

• Given in combination with other drugs (IV benzodiazepine with opioid analgesic)

what is moderate sedation used for

Minor procedures and diagnostic tests - Endoscopy/colonoscopy, cardioversion, minor orthopedic or dental procedures

moderate sedation nursing interventions

• Monitor respiratory effort, oxygen saturation, cardiac rhythm, LOC, and ECO2

• Keep reversal agents (flumazenil and naloxone) immediately available

• Provide calm environment 

• Continue to monitor until patient is alert and v/s are stable

• Assess for delayed sedation, dizziness, or HOTN

• Educate patient to not drive or make major decisions for 24 hours after

local anesthetics key fx

• Block pain in specific area of the body

• Does not affect consciousness or breathing

types of local anesthetics

Can be central (spinal and epidural) or peripheral (nerve blocks, infiltration, topical, continuous nerve catheters for post-op pain)

drug examples of local anesthetics

• “Caines” - Lidocaine, bupivacaine, prilocaine, tetracaine

what can local anesthetics be combined with

• May be combined with epinephrine to reduce bleeding and prolonged duration

• never use epinephrine on areas with end arteries (fingers, toes, ears, nose) because it can cause tissue necrosis

drug effects of local anesthetics

• Autonomic activity lost first

• Pain and sensory lost second

• Motor activity lost last

• Recovery returns in opposite order: Motor function, pain/sensory, then autonomic

adverse effects of local anesthetics

usually limited - usually only occur if it enters blood stream

• HOTN

• bradycardia

• restlessness

• tremors

• seizure

• spinal headache (only with epidural or spinal -> can be treated with blood patch)

nursing interventions of local anesthetics

• Assess for allergies and previous reactions

• Monitor for signs of local toxicity (tinnitus, metallic taste, confusion, perioral numbness)

• If epinephrine is used in combination, monitor for tachycardia or HTN

• If spinal is used, keep patient flat for 6-8 hours after to reduce spinal headache risk

• Encourage fluids and caffeine post-op to help seal dural leak

• Reassure patient about temporary numbness or tingling after administration

neuromuscular blocking drugs key fx

• Results in paralysis of skeletal and smooth muscles by blocking nerve transmission

• Used in combination with general anesthetics to facilitate intubation, control ventilation, reduce muscle contractions, and in diagnostic doses for myasthenia gravis

• Patient remains conscious, no sedation or pain relief 

what has to be used when neuromuscular blocking drugs are used in surgery

artificial ventilation required and patient must be adequately anesthetized

effects of neuromuscular blocking drugs

• Muscle weakness

• Total flaccid paralysis

adverse effects of neuromuscular blocking drugs

• HOTN

• vasodilation

• bradycardia/tachycardia

• hyperkalemia (succinylcholine only)

contraindications of neuromuscular blocking drugs

malignant hyperthermia

drug interactions of neuromuscular blocking agents

• aminoglycosides

• clindamycin

• calcium channel blockers

• mag sulfate

• diuretics 

• ^Additive effects

nursing interventions of neuromuscular blocking agents

• After surgery, monitor for full return of muscle strength and airway control before extubation

• Ensure airway and ventilatory support prior to administration

• Label IV lines clearly and verify correct drug

• Continuously monitor oxygenation, ECG, and muscle twitch response using nerve stimulator

what are the two classes of neuromuscular blocking drugs

• depolarizing - succinylcholine

• nondepoloarizing - rocuronium

depolarizing NMBDs key fx

• succinylcholine

• Causes initial muscle contraction, followed by a prolonged depolarization because it isn’t broken down quickly

• Causes flaccid paralysis

• Monitor for twitching, potassium levels, and malignant hyperthermia

non depolarizing key fx

• rocuronium

• Prevents muscle contraction all together

• Used to facilitate intubation and maintain skeletal muscle relaxation during surgery

• Monitor depth of blockage using nerve stimulator and be prepared to administer reversal agents once procedure ends

• Reversal agent/antidote: Neostigmine and pyridostigmine