General and Local Anesthetics Flashcards
1
Q
Anesthetics
A
- drugs that eliminate pain by depressing nerve function in the central and peripheral nervous system
- produces a state of reduced neurologic function
2
Q
General anesthesia (what happens)
A
- complete loss of consciousness and loss of body reflexes
- including paralysis of respiratory muscles
3
Q
Local Anesthesia
A
no paralysis of respiratory function
Elimination of pain sensation in the tissues that are anesthetized
4
Q
General anesthetics (route)
A
inhaled, parenteral
5
Q
Overton-Meyer theory
A
- for all anesthetics, potency varies directly with lipid solubility
- fat-soluble drugs are stronger anesthetics than water-soluble drugs
- lipid-soluble anesthetic drugs can therefore easily cross the BBC to concentrate in nerve cell membranes
6
Q
General Anesthetics (contraindications)
A
- pregnancy
- acute porphyria
- malignant hyperthermia
- monitor vital signs (sudden increase in temp, BP, HR), o2 saturation, ABCs, baseline labs
7
Q
How do general anesthetics start taking effect?
A
- begins loss of senses (sight touch, taste, smell, hearing, consciousness
- cardiac and pulmonary are last to lose function because they are controlled by the medulla
- function returns in the opposite way
8
Q
Malignant hyperthermia
A
- occurs during or after inhaled general anesthesia or use of NBD succinylcholine
- sudden elevation of the body tem (above 104F)
- tachypnea, tachy cardia, muscle ridifity
- life-threatening emergency
- treated with cardiorespiratory supportive care and dantrolene (skeletal muscle relaxant) reverses succinylcholine)
- at risk for anyone in the family who has had it before
9
Q
General Anesthetics (adverse effects )
A
- in large doses life-threatening
- cardiac and respiratory suppression common
- use with caution on someone with beta-blockers or other meds that cause myocardial depression and antihypertensives with lower blood pressure
10
Q
Dexmedetomidine (Precedex)
A
- provides sedation and analgesia without respiratory depression
- used for procedural sedation and surgeries of short duration. Also used in the ICU to sedate patients on mechanical ventilation
- short half-life
11
Q
Ketamine
A
- used in both general anesthesia and moderate sedation
- can be given IM, IV, or SUbQ
- low incidence of cardiovascular or respiratory depression
Adverse effects: hallucinations
12
Q
Nitrous Oxide
A
“laughing gas”
-used primarily for dental procedures or as a supplement for more potent anesthetics
13
Q
Propofol (Diprivan)
A
- parenteral general anesthetic
- used for induction and maintenance of general anesthesia and for sedation in the ICU for mechanical ventilation
- can be used in lower doses for moderate sedation
- Adverse effects: can increase triglycerides because it is in a lipid-based emulsion
14
Q
Moderate Sedation
A
- also called conscious sedation and procedural sedation
- does not cause complete loss of consciousness and does not normally cause respiratory arrest
- anxiety and sensitivity to pain are reduced, and the patient cannot recall the procedure
- preserves the patient ability to maintain own airway and to respond to verbal commands
- used for diagnostic procedures and minor surgical procedures that do not require deep anesthesia
- rapid recovery time and greater safety profile than general anesthesia
- combination of an IV benzodiazepine (midazolam) or propofol an opiate analgesic (fentanyl/morphine)
15
Q
Local Anesthetics (route)
A
- topical: applied directly to skin or mucous membranes (creams, solutions, ointments, gels, ophthalmic drops, powders, suppositories
- parenteral: injected directly into the tissue or into the CNS by various spinal injection techniques
- spinal or intraspinal: intrathecal, epidural (regional anesthesia)
- nerve block (deep injection for the never root)
- infiltration (several small injections around area for anesthesia)
- peripheral nerve catheter attached to a pump containing the local anesthetic
