NIS numbers Flashcards
magnetic field strength above which a patient with an implanted cardiac pacemaker should NOT be allowed
5 Gauss (0.5 mT)…………………… (1 Gauss = .0001 Tesla, or 1 Tesla = 10,000 Gauss)
reversal of midazolam
Flumazenil 0.2 mg IV
hearing protection must be provided for MRI exams in which sound pressure exceeds:
99 decibels
what radiation level can ring dosimeters detect
30 mrem of gamma and 40 mrem of beta
how many hospital deaths per year were attributable to medical errors
44,000-98,000 deaths
(2000 IOM To Err is Human)
societal cost of medical erros
$17-29 billion dollars
(2000 IOM To Err is Human)
how many Americans experience a diagnostic error or know someone how did?
1 out of 6 ppl
What % of postmortem exams were associated with diagnostic erros
10%
ASA class I
A normal healthy patient
ASA Class II
A patient with mild systemic disease
ASA Class III
A patient with severe systemic disease
ASA Class IV
A patient with severe systemic disease that is a constant threat to life
ASA Class V
A moribund patient who is not expected to survive without the operation
ASA Class VI
A declared brain-dead patient whose organs are being removed for donor purposes
ages where kids experience a gradual transition to self determination
12-18 years
Age cut off for medical decision making
< 12 yo cannot make their own decisions.
Between 12-18 is a gray area and you have to determine 3 things:
- legal determination of maturity
- evidence the child is sufficiently mature to make own decisions
- conditions exempting parental consent
time peroid for hand washing with soap and water
15 seconds
time period for washing hands with hand sanitizer
20 seconds
All MR sites should have a handheld magnet ( >________Gauss)
All MR sites should have a handheld magnet ( >1000 Gauss)
……” or handheld ferromagnetic detection device, which allows for testing of external objects and some superficial internal implants”
pg 21
insulating pads for the MRI scanner are necessary to keep skin at least _______ from the skin surface
1 -2 cm
insulating pads for the MRI scanner are necessary to keep skin at least 1-2 cm from the skin surface
volume of liquid Helium in MR scanners
typically 1500 to 2000 L
temperature of liquid helium in MRI scanners
-269 C, 4 K
When the magnet is quenched, what is the increase in volume from He liquid to gas
760 fold increase in volume
incidence of severe life threatening allergic like reactions
estimated to be 0.01% to 0.04%
incidence of allergic like CT contrast rxn
< 1%
most of which were mild
risk of another allergic like rxn to the same class of contrast media if you have had a rxn before
5 x increased risk
increased risk of adverse contrast rxn in a patient with allergies or asthma
2-3 x increased risk
time period in which thyroid cancer pts should not receive CT IV contrast before I-131 treatment
No IV contrast 4-6 weeks before I-131 treatement
contrast will saturate the thyroid and could render treatment ineffective
even if pre-medicated, if a breakthrough contrast rxn occurs what % are similar severity to the initial contrast rxn
80%
“Even with appropriate use of an accepted premedication regimen, breakthrough reactions occur in a small number of high-risk patients. When they do occur, they are of similar severity to the initial reaction about 80% of the time, less severe about 10% of the time, and more severe about 10% of the time.”
pg 25
PC-AKI is defined as kdiney injury within what time perioid of contrast administration
24-48 hours
CIN is most likely to develop in pts with GFR < _____ mL/min/1.73 m2
GFR < 30
…or AKI
Administration of large or multiple doses of contrast media within __________ may also be a risk factor for AKI
24-48 hours
pg 26
AKI should be diagnosed whenever:
1) an absolute serum creatinine increase of at least 0.3 mg/ dL; or
2) a percentage increase in serum creatinine of at least 50% (1.5-fold above baseline); or
3) a reduction in urine output to 0.5 mL/kg/h for at least 6 hours.
usual clinical course of PC-AKI (time periods)
- a rise in serum creatinine beginning within 24 hours of contrast media administration,
- peaking at about 4 days
- and then usually returning to baseline by 7 to 10 days.
If a potentially at-risk patient’s condition is stable, a creatinine value within _____________ of contrast administration is generally considered sufficient.
30 days
pg 27
The American College of Radiology Committee on Drugs and Contrast Media currently recommends that no precautions are necessary in diabetic patients taking metformin, unless the eGFR is < _____________ mL/min/1.73 m2 (in which case the patient should not be taking metformin anyway)
<30
a diabetic patient is on metformin and their GFR is < 30, so you hold their metformin. How long do you hold it for?
withheld for 48 hours after contrast media administration and only reinstituted if the renal function is reassessed and found to be acceptable.
how much maternally administered contrast media enters breast milk?
1%
Of contrast media that makes it into breast milk, what % is absorbed through an infant’s Gi tract?
1%
The reported overall rate of extravasation with power injection for CT ranges from _____________%
The reported overall rate of extravasation with power injection for CT ranges from 0.1% to 1.2%.
if indwelling lines have been in for _______ is there an increased risk for extravasation when power injecting with CT IV contrast?
24 hours
Patients are believed to be at increased risk for extravasation when:
- more peripheral access sites are used (such as the hand, wrist, foot, and ankle) rather than the antecubital fossa,
- when utilized indwelling lines have been in place for more than 24 hours (in which case some degree of phlebitis may be present),
- and when there are multiple punctures into the same vein.
What % of extravasation injuries resolve without adverse sequelae?
98%
In the remaining 2% of injuries, some patient morbidity develops because contrast media can damage adjacent tissue, likely due to a combination of direct toxic effects and its hyperosmolality.
Adverse effects are usually self-limited, most commonly consisting of prolonged pain or swelling.
Severe extravasation injuries (compartment syndrome) occur in _________% of patients with extravasations.
<1%
% gad excreted into breast milk
0.04%
% gad contrast absorbed by baby’s gut after drinking breast milk from mom who just got gad
1%
who gets NSF
CKD
with GFR < 30 mL/min/1.73 m2
specifially:
- Stage 4: GFR 15-29 mL/min/1.73 m2
- Stage 5: GFR < 15 mL/min/1.73 m2
pt with eGFR < 30 mL/min/1.73 m2. What three high risk GBCM are absolutely contraindicated
- gadodiamide [Omniscan®],
- gadoversetamide [OptiMark®],
- gadopentetate dimeglumine [Magnevist®]
mild reaction to contrast media time frame
usually resolve in 20-30 min and do NOT require medical treatment
for hypotensive patient, what position do you put them in?
Elevate legs at least 60 degrees (Trendelenburg position)
% of radiologists named in medical malpractice lawsuits each year
7%
indemnity payment (a sum of money paid as compensation) average in malpractice cases
$480,000
how much time does the average radiology spend in their career with an unresolved open malpractice claim?
19 months
level 1 results must be communicated within what timeframe?
(tension pneumothorax, ruptured aortic aneurysm, acute intracerebral hemorrhage, and pneumoperitoneum)
60 minutes
level 2 results must be communicated within what timeframe?
12 hours
reading room ambient lighting
25-50 lux
maximum gray value luminance for diagnostic monitors
350 dd/m2
maximum gray value luminance for mammo monitors
420 cd/m2
lossless compression of file size
3:1
lossy compression ratio
10:1
compression ratios of lossy and lossless
Lossy is 10:1
lossless is 3:1
how much downtime is allowed per year
50 minutes of downtime per year
high availability systems are expected to perform at:
“four nines”… or 99.99% of uptime
