miscellaneous topics overview part 2 (continued) Flashcards
Surgical Care Improvement Project has 7 measures designed to reduced postop surgical site infection
- prophylactic abx within 60m of surgical incision (vanc is 120m)
- choice of abx determined by site of surgery
- d/c’d 24h post surgery (48h for cardiac patents)
- cardiac surgical patients must achieve glycemic control (<200mg/dL)
- postop wound infection is diagnosed during initial hospitalization
- surgical patients receive appropriate hair removal
- colorectal patients are normothermic upon arrival to PACU (>36c)
precautions for covid
airborne
creutzfeldt jakob disease
prion disease, can lead to encephalopathy and dementia. etiologies: consumption of contaminated animal protein, contaminated implants (corneal or dural tissue), cadaveric pituitary hormone supplementation.
how to dx TB
skin test (+) >10mm induration and (+) CXR
tx for TB
isoniazid first line (se: peripheral neuropathy and hepatotoxicity). can include pyroxidine to reduce incidence of liver damage
rifampin (se: TCP, leukopenia, anemia, kidney failure. urine sweat and tears will take on an orange/red color
other first line: pyrazinamide, streptomycin, ethambutol
TB special anesthetic considerations
anesthesia provider should wear N95
HEPA between y piece and patients aw
bacterial filter on expiratory limb of circle circuit
ideal: dedicated anesthesia machine and ventilator
pre and post op care in negative pressure isolation room
elective procedures should be delayed until patient is on anti TB chemo, has 3 negative active fast bacillus tests, demonstrates sx improvement
WBC’s can be divided into _________ and __________
granulocytes (neutrophils, basophils, eosinophils)
agranulocytes (monocytes, lymphocytes)
basophils overview
essential component of allergic rxn
releases histamine, leukotriene, prostaglandins (mast cells do same thing)
epinephrine prevents degranulation (release of intracellular contents) by binding to B2 receptors on cell membrane
monocytes overview
fights bacterial, viral, or fungal infections (phagocytosis)
release cytokines
present pieces of pathogens to T lymphocytes
types of lymphocytes
B lymphocytes (humoral immunity- produce antibodies)
T lymphocytes (cell mediated, does not produce antibodies)
NK: limit spread of tumor and microbial cells
(fx is reduced by opioids)
hypersensitivity reactions cause and effect
type 1: immediate hypersensitivity reaction
antigen and antibody interaction in a patient who has been previously sensitized to the antigen
IgE mediated
tryptase is released from mast cells during allergic reaction. it is therefore best lab test to determine if allergic response has occurred
ex) anaphylaxis, extrinsic asthma
type 2: antibody mediated reaction
IgG and IgM bind to cell surfaces of extracellular regions
reaction activates complement cascade
ex) ABO incompatibility, HIT
type 3: immune complex mediated reaction
immune complex is formed and deposited into patients tissue (normally these complexes are cleared from body)
reaction activates complement cascade
ex) snake venom
type 4: delayed
delayed at least 12 hours following exposure
ex) contact dermatitis, graft v host reaction, tissue rejection
tx of intraop anaphylaxis
d/c offending agent
increase FiO2, provide aw support
epi 5-10mcg IV for HoTN and .1-1mg IV for CV collapse
liberal IV hydration (crystalloid 10-25mL/kg or colloid 10mL/kg. repeat PRN)
H1 receptor antagonist (diphenhydramine .5-1mg/kg IV)
H2 receptor antagonist (ranitidine 50mg IV or famotidine 20mg IV)
hydrocortisone 250mg IV (prevents delayed release of inflammatory compounds, does not produce immediate effect)
albuterol for bronchospasm
vasopressin for refractory HoTN (start at 0.01unit/min)
common culprits for periop allergic rxn’s
- NMB’s (most common, and succ is most common NMB)
- latex (high risk groups: spina bifida, myelomeningocele, atopy, healthcare workers, allergy to banana, kiwi, mango, papaya, pineapple, tomato
- abx (beta lactams are most common)
- others: chlorhexidine, protamine, contrast media, colloids, blood products, opioids, hypnotics, LA’s
review the chemotherapeutic agents this “chemo man” represents and the unique SE’s
Cisplatin (alkylating agent)–> acoustic nerve injury and nephrotoxicity
Vincristine and vinblastine (tubulin binding drug)–> peripheral neuropathy
Bleomycin (antitumor antibiotic)–> p.fibrosis (keep FiO2 <30%)
Doxorubicin (antitumor antibiotic)–> cardiotoxic
5-fluororacil (antimetabolite)–> bone marrow suppression
Methotrexate (antimetabolite)–> bone marrow suppression
most chemotherapeutic agents cause which two things? and which agent is the exception?
bone marrow suppression and thrombocytopenia. bleomycin is the exception
Tamoxifen uses and SE’s
selective estrogen receptor modulator. if the tumor does not express estrogen receptors, it does not respond to this drug.
SE’s hot flashes, increase risk of endometrial cancer
5 key hormones that regulate digestive activity include
- gastrin
- secretin
- cholecystokinin
- gastric inhibitory peptide
- somatostatin
gastrin
role
site of production
stimulus
function
when food enters the stomach, gastrin increases stomach acid and stimulates chief cells to secrete pepsinogen.
in the presence of stomach acid, pepsinogen is converted to pepsin (aids in protein digestion)
produced in G cells in stomach
stimulus: food in stomach
function: increase gastric acid and pepsinogen secretion
secretin
role
site of production
stimulus
function
tells pancreas to secrete bicarb and liver to secrete bile
site of production: S cells (small intestine)
stimulus: acid in duodenum
function: increased pancreatic bicarb secretion, decreased gastrin secretion
cholecystokinin
role
site of production
stimulus
function
tell pancreas to release digestive enzymes and gallbladder to contract
site of production: I cells, small intestine
stimulus: food in duodenum
function: increase in gallbladder contraction (bile release), increased pancreatic enzyme secretion, decreased gastric emptying
gastric inhibitory peptide
role
site of production
stimulus
function
slows gastric emptying and stimulates pancreatic insulin release
site of production: K cells- small intestine
stimulus: food in duodenum
function: increased insulin release, decreased gastric acid secretion, decreased gastric motility
somatostatin
role
site of production
stimulus
function
universal off switch for digestion
site of production: D cells (pancreatic islet), stomach, small intestine
stimulus: food in gut, gastrin, CCK
function: decreases all GI function (enzyme and motility). universal “off” switch
what is increased in a patient with zollinger ellison syndrome
gastrin –>increased gastric acid–> increased ulceration
gallbladder pain after a fatty meal is caused by
CCK release
tx for carcinoid tumors
somatostatin
things that decrease gastric barrier pressure (aka lowering LES tone)
anticholinergics
cricoid pressure
pregnancy
things that increase gastric barrier pressure (aka increasing LES tone)
metoclopramide
things that don’t affect gastric barrier pressure aka LES tone
succ–>increased LES tone but increased intragastric pressure = 0 net charge
barrier pressure =
LES pressure - intragastric pressure
review direct sensory input to vomiting center (NTS) in medulla (3 pathways) and the receptors involved in each pathway
5HT3 antagonist
receptor target
ligand
examples and dosages
receptor target: 5HT3
ligand: serotonin
examples: ondansetron 4-8mg, granisetron 1mg, dolasetron 12.5mg
NK1 antagonists
receptor target
ligand
examples and dosages
receptor target: NK1
ligand: substance P
examples and dosages: aprepitant (PO) 40mg
dopamine antagonists
receptor target
ligand
examples and dosages
receptor target: D2
ligand: dopamine
examples and dosages:
droperidol .625-1.25mg
haldol .5-2mg
metoclopramide 10-20mg
prochlorperazine 10mg
antihistamines
receptor target
ligand
examples and dosages
receptor target: H1, M1
ligand: H1 (histamine), M1 (Ach)
examples and dosages:
diphenhydramine 25mg
hydroxyzine 12.5-25mg
promethazine 12.5-25mg
anticholinergics
receptor target
ligand
examples and dosages
receptor target: M1
ligand: Ach
examples and dosages:
scopolamine (transdermal) 1.5mg
steroids
receptor target
ligand
examples and dosages
receptor target: intracellular steroid receptors
ligand: steroid
examples and dosages:
dexamethasone 4-10mg
PONV patient risk factors
female
non smoker
hx motion sickness
previous PONV
age loosely associated (youth>elderly)
PONV surgical risk factors
surgical duration >1h
GYN procedures
laparoscopy
breast
plastics
peds procedures (strabismus, orchiopexy, T&A)
PONV anesthetic risk factors
halogenated anesthetics
nitrous oxide (>50%)
opioids
etomidate
neostigmine
is BBB well developed at CTZ
no, which explains why it is stimulated by noxious chemicals
motion induced nausea is the result of
H1 and M1 stimulation in the vestibular system of the inner ear
when should you apply transdermal scopalamine
> 4h before induction
SE of methyl methacrylate (bone cement) includes (basically describe bone cement implantation syndrome)
increases intramedullary pressure of bone that causes micro emboli. can result in VQ mismatch, increased dead space and in severe cases right heart failure
residual bone cement can enter systemic circulation where it causes bradycardia, dysrhythmias, HoTN, decreased SVR, pHTN (increased PVR), hypoxia, and cardiac arrest
highest risk of BCIS
hip arthroplasty
first signs of BCIS: awake versus asleep patient
awake: dyspnea, AMS
asleep: decreased EtCO2
first line tx for BCIS
100% FiO2, IV hydration, neo for HoTN
fat embolism syndrome
complication of long bone trauma. greatest risk inside first 72h of injury. explains why prompt stabilization of injury is important
risk factors of fat embolism syndrome include
pelvic fx, femoral fx, instrumentation of femoral medullary canal
triad of FES includes
respiratory insufficiency (hypoxemia, bilateral infiltrates on CXR, ARDS)
neurologic involvement (confusion to coma)
petechial rash (skin and neck of axilla, oral mucosa, conjunctivae
maximum inflate time of a pneumatic tourniquet
2h
inflation pressure of pneumatic tourniquet for UE versus LE surgery
UE: 70-90mmHg above SBP
LE: 2x over SBP
when pneumatic tourniquet is used for a bier block, what is the inflation pressure for UE versus LE
UE: 250mmHg or 100mmHg over SBP (whichever is higher)
LE: 350-400mmHg
releasing the pneumatic tourniquet produces transient changes that include
increased EtCO2
decreased core body temp
decreased BP
decreased SvO2 (SaO2 usually normal)
metabolic acidosis
tourniquet pain usually lasts how long after inflation
45-60m
-via c fibers, unresponsive to analgesics
ix COX1 always present? COX2?
COX1 is always present and maintains physiologic function. COX2 is not always present and is expressed during inflammation
drugs that perform non selective cox inhibition include
ASA
ibuprofen
naproxen
ketorolac
diclofenac
indomethacin
COX2 selective inhibition drugs
celecoxib and any drugs with the suffix -coxib
key complications of COX inhibitors
ketorolac 30mg IV ~ morphine _____ IV
10mg
aspirin toxicity can cause a
gap metabolic acidosis
Samters triad
ASA associated respiratory disease.
asthma, allergic rhinitis, nasal polyps
-patients can develop life threatening bronchospasm after admin of asa or other NSAIDS
ephedra (ma huang)
use
interactions and toxicity
d/x before surgery
use: diet aid, athletic enhancer, nasal decongestant
interactions and toxicity: interaction with MAOI’s–> serotonin syndrome
sympathomimetic effects
catecholamine depletion with long term use –> hemodynamic instability
d/x before surgery: 24h
garlic
use
interactions and toxicity
d/x before surgery
use: anti platelet, HTN, HLD
interactions and toxicity: increase bleeding risk, decrease serum glucose
d/x before surgery: 7 days
ginger
use
interactions and toxicity
d/x before surgery
use: nausea
interactions and toxicity: increased bleeding risk
d/x before surgery: no data
ginkgo balboa
use
interactions and toxicity
d/x before surgery
use: anti aging, poor circulation
interactions and toxicity: increased bleeding risk
d/x before surgery: 36h
ginseng
use
interactions and toxicity
d/x before surgery
use: antioxidant
interactions and toxicity: increases bleeding risk, enhances SNS effects of sympathomimetics, may cause Hoglycemia (risk in fasting patient)
d/x before surgery: 7 days
kava kava
use
interactions and toxicity
d/x before surgery
use: anxiety
interactions and toxicity: decreases MAC (increases GABA), may prolong DOA of anesthetic agents
d/x before surgery: 24h
licorice
use
interactions and toxicity
d/x before surgery
use: gastric and duodenal ulcers
interactions and toxicity: mimic effects of aldosterone. Na/H2O retention and therefore decreased K, can be confused with conns syndrome
d/x before surgery: no data
saw palmetto
use
interactions and toxicity
d/x before surgery
use: BPH
interactions and toxicity: increased bleeding risk
d/x before surgery: no data
st johns wort
use
interactions and toxicity
d/x before surgery
use: depression
interactions and toxicity: induction of CYP3A4, decreases serum levels of warfarin, protease inhibitors, digoxin, may prolong DOA of anesthetic agents, interaction with MAOI’s and meperidine–> serotonin syndrome
d/x before surgery: 5 days
valerian
use
interactions and toxicity
d/x before surgery
use: anxiety
interactions and toxicity: decreases MAC (increases GABA), may prolong DOA of anesthetic agents, abrupt d/c may cause withdrawal (d/c over weeks)
d/x before surgery: no data
4 G’s that increase risk of bleeding
garlic, ginger, ginkgo, ginseng
tasks to complete before every patient include
- verify adequate suction
- verify presence and function of required monitors and alarms
- check that vaporizers are filled and that ports are tightly closed
- determine that CO2 absorbent is not exhausted
- perform high pressure leak test
- assess unidirectional valves
- document that procedures listed above were completed
- set ventilator appropriately and conduct anesthesia TO
- O2 monitor must be calibrated once a day (not before every case)
american society for testing and materials
sets standards for required components of anesthesia machine (ASTM F1850)
US DOT is responsible for
setting standards for compressed gas cylinders
FDA sets standards for
food and drugs, also created 1993 FDA anesthesia machine pre check out procedures
OSHA sets standards for
acceptable occupational exposure to volatiles
4 zones for MRI, definition, and example
are ferromagnetic objects allowed in zone 4
no
safe metals for MRI include
stainless steel, titanium, aluminum, copper
color of MRI safe cylinders
silver with color code at top
overview of modified aldrete score (and what it includes- 5 areas)
used to assess readiness to discharge from PACU
minimum modified aldrete score that correlates with PACU discharge?
9 or greater
2 anti emetic drug groups that can be used in the parkinson population
anticholinergics
NK1
