Anesthesia Flashcards
Max dose of epinephrine non-cardiac / cardiac
.2mg / 0.04mg
Sulfa allergy has greater incidence to which class of local anesthetic
Esters
Max dose 2% lidocaine
4.4mg/kg or 300mg
Max dose 4% articaine
1.3mg/kg or 90mg
How many mg of 1% anesthetic in 1.7ml
17mg
How many mg of epi in 1:100,000 1.7ml
0.02mg
Which vasocontrictor additive in LA has alpha agonism resulting in increased MAP and reflex braycardia (good for tachycardic patients)
Levonordefrin
Which vasocontrictor additive in LA has beta agonism and is better for hypertensive patients
Epinephrine
NPO time for breast milk
4hrs
Role and mechanism of Train of Four
- Depolarizing –> uniform decrease in twitch amplitude in TOF - Non depolarizing –> sum of twitches based on % of receptors occupied. 1 twitch 95%, 2 twitches 85%, 3 twitches 80%, 4 twitches 75% makes sense because minimum 25% available receptors for NMJ function
Role and mechanism of Tetanic nerve stimulator
Depolarizing –> no fade in muscle response with tetany (if there is fade then there has been prolonged exposure to succinylcholine or phase 2 blockade) - Non depolarizing –> fade with tetany
Why is Sp02 falsely elevated in CO poisoning and heavy smokers?
CO poisoning and heavy smokers have increased carboxyhemoglobin which falsely elevates SpO2
Which leads most sensitive to ST elevation
Lead II Lead V5
Which volatile agent has airway irritation
Desflurane
Which volatile agent has slow onset
Isoflurane
While volatile agent may be contraindicated in renal patient?
Sevoflurane (compound A)
What hemodynamic effects do all volatile agents have
hypotension tachycardia decreased contractility decreased systemic vascular resistance
What ventilation effects do volatile agents have? (Exception-Isoflurane)
Tachypnea Hypercapnea Decreased Tv Decreased minute ventilation
Mechanism of Miosis with opioid
CN III parasympathetic agonist
Site of propofol metabolism
liver
All IV sedation agents decrease cerebral blood flow and ICP except
Ketamine
Mechanism of neostigmine
Build up of ACh within NMJ. It is an acetyl cholinesterase inhibitor
Dose of neostigmine
0.03-0.07 mg/kg
Contraindications of Succinylcholine
Recent burn/crush injury NMJ disease Narrow angle glaucoma Malignant hyperthermia Skeletal muscle myopathies
Which two neuromuscular blocking agents are best for renal or hepatic failure patients
Atracurium Cisatracurium (Hoffman Elimination)
s/s cocaine intoxication
HTN, Tachy, hallucinations, convulsions, HA, Angina, CVA
Tx cocaine intoxication
B-blockers Nitrates CCB
Cocaine half-life
30-90 mins
Main difference between cocaine detox and EtOH detox
EtOH detox also has HTN/Tachycardia
Age/gender most common for thyroid storm
Women 20-40 yrs
Most common cause underlying condition in thyroid storm
recently diagnosed/undiagnosed Grave’s disease with trauma/surgical stress
s/s thyroid storm
HTN, Tachy, MI, dysrhythmias, Hyperthermia
Main difference in s/s between thyroid storm and MH
MH also has acidosis
Emergent tx of thyroid storm
Propranolol
What medications can be given 6-8 weeks prior to elective surgery in patient with recently diagnosed Grave’s Disease
Propylthiouracil Prevents conversion of T4 to T3, inhibits thyroid hormone stimulation
How many mins reserve O2 does obese person have?
2mins
What common maneuver worsens air trapping in bronchospasm?
PEEP It can cause lung hyperinflation.
Pathophysiology of MH
Calcium dump from sarcoplasmic reticulum in skeletal muscle
Early signs of MH
Hypercarbia Tachy Tetany
Late signs of MH
Hyperkalemia with ECG changes Rhabdo Hyperthermia
Most common causes of death in MH
Hypercoagulation 2/2 hyperthermia Hyperkalemia
Loading dose of dantrolene for MH
2.5mg/kg
s/s myasthenic crisis vs cholinergic crisis
SAME signs/symptoms Weakness, bronchospasm, diaphoresis, cyanosis
Myasthenic crisis vs cholinergic crisis
Myasthenic crisis = insufficient medication Cholinergic crisis = excess medication
Most common myasthenia gravis medication and its duration of effect
Pyridostigmine = Anti-Acetylcholinesterase 3-6 hour duration
Which volatile agents are potent bronchodilators
Isoflurane Enflurane
Which paralytics cause histamine release and are contraindicated in asthmatic
Atracurium Mivacurium
Classification of cerebral palsy
Spastic (motor cortex, 75% of CP patients) Dyskinetic (basal ganglia) Ataxic (cerebellum)
Periop management of CP
Volatile induction (IV access hard with contractures) Aspiration precautions (decreased tone + hypersalivation) Avoid Succinylcholine Increase MAC and non-depolorizing dose Lowered seizure threshold Chronic hypovolemia with pre-renal kidney injury/failure
What LA agents can cause methemoglobinemia at high doses?
Prilocaine
