complications Flashcards
Top 3 ASA closed claims
Death
Nerve Injury
Brain damage
3 biggest human errors leading to preventable anesthetic accidents
Medication errors**
IV line disconnection (or infiltration)
Anesthesia machine misuse
which 3 settings are associated with awareness*
major trauma**
obstetrics
cardiac surgery
awareness rate
0.1-0.4%
scopolamine has what kind of effect
retrograde amnesia
most common eye injury*
corneal abrasion
most common cause of post op loss of vision
ischemic optic neuropathy
Ischemic Optic Neuropathy
optic nerve infarction due to decreased oxygen delivery via one or more arterioles supplying the optic nerve
(ischemic optic nerve from hypotension, etc.)
ION is commonly reported after which surgeries
cardiopulmonary bypass
radical neck dissection
abd and hip procedures
spinal surgeries in prone
contributing patient factors to ION
HTN, DM, CAD, Smoking
3 positions that compromise venous outflow
prone
head down
compressed abd
onset of ION
immediately and through 12 post op day
prevention of ischemic optic neuropathy: enhance venous outflow by positioning the patient
head up
Most common CV event after non cardiac surgery
MI*
5% patients > 45 yo
Spinal anesthesia severe complication?
cardiac arrest
Spinal anesthesia cardiac arrest c/o associated with
high level of block (T4)
fast injection time
Signs and sx prior to cardiac arrest with spinal anesthesia
- gradual ↓ in HR and BP (<20% of baseline)
- ↓ HR
- ↓ BP
- cyanosis
check if can wiggle fingers
4 types of hypersensitivity reactions
type 1 immediate, type 2 cytotoxic, type 3 immune complex, type 4 delayed, cell-mediated
anaphylaxis
exaggerated response to an allergen that is mediated by a type 1 hypersensitivity reaction
anaphylaxis appears within
minutes of exposure
prevention of ION - minimize ___ constriction
abd
prevention of ION: limit degree and duration of ___
deliberate hypotension
prevention of ION: avoid ___ (think blood)
anemia
cardiac accelerators are
T1-T4
3 drugs for CPB arrest after spinal
ephedrine, atropine, epi
what causes hearing loss after spinal
CSF leak
what do you treat hearing loss due to csf leak with
blood patch
what is an allergic reaction
eggaterated immunologic response to antigenic stimulation a previously sensitized individual
antigen or allergen is typically
a protein, a polypeptide, or smaller molecule that is covalently bound to a carrier protein
first exposure in anaphylactic reaction what happens
antigen - b cell- IgE binds to surface of mast cell
second exposure of antigen
causes the cell to release histamine and histamine increases the permeability and distention of the blood capillaries
allergic reaction: pt can lose up to 50% of ___ volume into the ____ space
intravascular , extravascular
type 1 immediate allergic reaction
atopy, urticaria, angioedema, anaphylaxis
type 2 cytotoxic allergic reaction
hemolytic transfusion reactions, autoimmune hemolytic anemia, heparin induced thrombocytopenia,
type 4 delayed, cell-mediated
contact dermatitis
latex is type
4
graft rejection is type
4
RA is type
3
blood type incompatibilities is type
2
anaphylaxis presents as
acute resp distress and/or circulatory shock
incidence of anaphylactic reactions during anesthesia
1:500 to 1:25000
mediators of anaphylaxis
histamine, leukotrienes, BK-A, platelet-activating factor
CV anaphylaxis
hypotension, tachycardia, arrhythmias
anaphylaxis pulmonary
bronchospasm, cough, dyspnea, pulm edema, laryngeal edema, hypoxia
dermatologic manifestation of anaphylaxis
uticaria, facial edema, pruritis
anaphylactoid reactions
resemble anaphylaxis but doe not depend on IgE antibody interaction with antigen (pt doesnt have to be exposed to the antigen prior)
4 risk factors associated w hypersensitivity to anesthetics
female, atopic history, preexisting allergy, previous anesthetic exposure
treatment of anaphlaxis - epi dose
0.01-0.5mg IV or IM
treatment of anaphlaxis - drugs
diphenhydramine (H1 blocker),Ranitidine (H2 blocker), hydrocortisone or methylpred
what are the most common cause of anaphylaxis during anesthesia
muscle relaxants
what is the mechanism for allergic reaction to muscle relaxants
anaphylaxis - IgE antibody directed against tertiary or quaternary ion epitope
hypotic agent that cause allergic reaction
pentothal propofol
ester local anesthetic allergic reaction
IgE mediated, share common antigenicity with PABA
amide local anesthetic allergic reaction
paraben or methylparabel
second most common cause of anaphylaxis d/t anesthesia
latex
foods that cross react with latex
mango, kiwi, chestnut, avocado, passion fruit and banana
how do you pre-treat someone for latex allergy
h1 and h2 histamine
occurane of MH in bed
1:15,000
occurrence of MH in adult
1: 40,000
MH causes what acid bace imbalance
metabolic acidosis
signs of Mh -jaw
masseter spasm
electrolyte imbalance in MH
hyper K, NA, Phos, CK, myoglobinemia, myogloinuria
late sign of MH -
core temp rise 1 degree C every 5 min
MH hyperkalemia caused by
efflux of K from muscle cells and systemic acidosis
drug that trigger MH
halogenated agent and depolarizing muscle relaxant (succs)
dantrolene doe
2.5mg/kg
max dose of dantrolene
10mg
how to treat hyperkalemia
dextrose 25-50g IV, regular insulin 10-20units IV
what does insulin do to K
forces it into the cell
albuterol in treatment of hyperk
beta 2 agonist, pushes K into the cell
bicarb
pushes K back into cell
how does dantrolene work
interfere with muscle contraction by binding ryr1, inhibit CA ion release from sarcoplasmic reticulum
side effects of dantrolene
muscle weakness, resp insufficiency, risk of aspiration, phlebitis
larynogospasm
complete spasmodic closure of the larynx as a consequence of an outside stimulus. closer of the glottis as a result of reflex obstruction of the laryngeal muscles
complete larynogospasm
silent paradoxical movement of the chest, tracheal tug, and no ventilation
partial larynogospasm
crowing noise
laryngospasm treat with
deepen patient, CPAP
signs of bronchospasm
prolonged expiration, high inflation pressures, exp wheezes, decreased O2 sat
increasing circuit pressure is a sign of
bronchospasm
wheezing is a sign of
bronchospasm
bronchospasm best tx with
anesthetic gas
bronchospasm tx med
epi, albuterol
3 things on the fire triangle
heat, fuel, oxygen
maximum acceptable trace concentration of N20
<25ppm
maximum acceptable trace concentration of N20 and halogenated agent
<25 ppm and 0.5HA
maximum acceptable trace concentration of halogenated agent only
~2 ppm
inverse square law
amt of radiation changes inversely with the square of the distance.
exposure at 4m will be ___ of that at 1m
1/16
maximum occupational whole body exposure annually is
5rem/year
maximum occupational whole body exposure annually is
5rem/year
sensory innervation (afferent) apex
SNL internal
motor innervation (efferent)
SLN external + RLN
bronchospasm will give you prolonged
expiration
bronchospasm will give you high ___ presures
inflatoin
STPC
standard color, tall man lettering. technology (scanning), pharmacy (pre-mixed/pre-filled), culture (nonpunative)
