RD patient care and safety

Question 1

1. Mechanism of contrast induced nephropathy
   a. ATN due to toxic effect on tubules
   b. Increased viscosity of contrast agent
   c. Ischemia of end arteries
   d. Interstitial nephritis
   e. Occlusion of tubules

Answer 1

a. ATN due to toxic effect on tubules MOST true
The best data related to the pathogenesis of contrast nephropathy come from animal models. Some studies show evidence of acute tubular necrosis (ATN), although the mechanism is not well understood [14-16]. The two major theories are renal vasoconstriction resulting in medullary hypoxemia, possibly mediated by alterations in nitric oxide, endothelin and/or adenosine, and direct cytotoxic effects of the contrast agents [UTD].The exact underlying mechanisms of nephrotoxicity have yet to be fully elucidated but are likely to involve the interplay of several pathogenic factors (Fig. 1). Intrinsic causes include the following: increased vasoconstrictive forces, decreased local prostaglandin- and nitric oxide (NO)-mediated vasodilatation, a direct toxic effect on renal tubular cells with damage caused by oxygen free radicals, increased oxygen consumption, and increased intratubular pressure secondary to contrast-induced diuresis, increased urinary viscosity, and tubular obstruction, all culminating in renal medulla ischemia.[33–35] Intrinsic causes act in concert with harmful extrinsic (prerenal) causes such as dehydration and decreased effective intravascular volume. [Emedicine/Medscape]

Question 2

2. 40 year old man about to have CT abdo pelvis. When consenting, what is the risk of radiation-induced tumor?
   a. 1 in 10
   b. 1 in 100
   c. 1 in 1000
   d. 1 in 10000
   e. 1 in 100000

Answer 2

c. 1 in 1000

According to RANZCR “Inside Radiology”, none of the above…
CT abdomen stochastic risk = 0.05% = 0.0005 = 1 in 2000

RSNA says CT abdo is “low risk” = 1 in 10,000 to 1 in 1000

Question 3

3. NSF - features not seen in first 2-3 months?
   a. Pruritis
   b. Swelling
   c. Rash (Erythema)
   d. Pain
   e. Organ fibrosis

Answer 3

e. Organ fibrosis F (lesions evolve into fibrous plaques in dermis/SC tissues; also in muscle, heart, liver & lung)

Nephrogenic systemic fibrosis
3. NSF - features not seen in first 2-3 months?

a. Pruritis T (do get this early)
b. Swelling T
c. Rash (Erythema) T
d. Pain T
e. Organ fibrosis F (lesions evolve into fibrous plaques in dermis/SC tissues; also in muscle, heart, liver & lung)

Question 4

Management of contrast extravasation. Best approach

a. aspirate, ice, compression, neurovasculr abs.
b. review by plastics.
c. discharge with GP f/u
d. compression, haemorrhoid cream

Answer 4

a. aspirate, ice, compression, neurovasculr abs.

Question 5

Which is definitely safe for MRI:

a. pacemaker
b. hip replacement.
c. epidural stimulator
d. aneurysm clip

Answer 5

• B – T = Hip replacement – may be MR safe, but undergo significant heating

According to RANZCR MRI Safety guidelines:
• A – F = Pacemaker – generally strictly contra-indicated (new “MRI conditional” pacemakers available – AJR11)
• B – T = Hip replacement – may be MR safe, but undergo significant heating
• C – F = spinal stimulator (manufacturers say not for MRI)
• D – T = aneurysm coil can have MRI; aneurysm clip have risk of torque or deflection, esp. if pre-1995 & not labelled safeCoils from MRIsafety.com = for most coils, filters, stents and grafts that have been tested, it is unlikely that these implants would become moved or dislodged as a result of exposure to MR systems operating at 1.5-Tesla or less

Question 6

1. A patient has suffered harm in the imaging department during a procedure. You have informed the patient and have decided to follow the open disclosure national standards. Which of the following is the next most appropriate action:
   a. Express regret
   b. Enter the event on the hospital risk registry
   c. Perform a cost evaluation
   d. Requires mandatory reporting
   e. Notify the national event registry

Answer 6

a. Express regret T

1. A patient has suffered harm in the imaging department during a procedure. You have informed the patient and have decided to follow the open disclosure national standards. Which of the following is the next most appropriate action:
   a. Express regret T
   b. Enter the event on the hospital risk registry T but later on in flowchart
   c. Perform a cost evaluation F can occur (e.g. agree to costs etc.), but
   comes later & not on the flowchart
   d. Requires mandatory reporting T
   e. Notify the national event registry T

Management of adverse events – open disclosure (RANZCR Patient Safety Syllabus) •Advise supervisor immediately• Documentation – health care records, incident reports• Inform patient, demonstrate empathy• Adverse events register Open Disclosure Standard (Australian Commission on Safety and Quality in Health Care): Open disclosure is the open discussion of incidents that result in harm to a patient while receiving health care. The elements of open disclosure are:• an expression of regret (as early as possible, the patient & their support person should receive an expression of regret for any harm that resulted from an adverse event),• a factual explanation of what happened,• the potential consequences,• and the steps being taken to manage the event and prevent recurrence.

Question 7

2. When administering gadolinium, the component which is thought to contribute to NSF?
   a. Free gadolinium
   b. Chelate
   c. And combinations of essentially the above 2 choices

Answer 7

a. Free gadolinium

Ohs
Although a role for the chelated form of the less stable GCs has been proposed, the most commonly accepted hypothesis involves the gradual release of dissociated gadolinium in the body, leading to systemic fibrosis.

Ref: The role of gadolinium chelates in the mechanism of nephrogenic systemic fibrosis: A critical update. Crit Rev Toxicol. 2014; 44(10):895-913 (ISSN: 1547-6898)

Radiopaedia: “This could be due to transmetallation, which is the replacement of the gadolinium from the chelate and forming a free gadolinium ion, free gadolinium ions may then deposit in different tissues and result in inflammation and fibrosis.”

Previous answer:
c. And combinations of essentially the above 2 choices

Clinical and Experimental Dermatology. Volume 36, Issue 7, pages 763–768, October 2011.
Nephrogenic systemic fibrosis (NSF), previously known as nephrogenic fibrosing dermopathy, is a generalized fibrotic disorder occurring in people with renal failure, following exposure to gadolinium-based contrast agents used to enhance MRI.
The cellular elements involved in pathology of NSF include bone-marrow-derived collagen-producing fibrocytes, myofibroblasts and activated macrophages.
Mechanisms that have been hypothesized to play a role in the pathogenesis of NSF include upregulation of osteopontin, imbalance between matrix metalloproteinases and tissue inhibitor of metalloproteinase 1, and presence of transforming growth factor-β, nuclear factor κB, decorin and metallothioneins.
Gadolinium (both free and chelated) is thought to be a bioactive trigger for NSF.

Question 8

3. You are about to perform a nephrostomy and the radiographer reminds you, that you need to take a “Team Time Out”. Which of the following is NOT part of a “Team Time Out”.
   a. Need to check correct site/side
   b. Need to have relevant imaging reviewed and available prior to procedure
   c. Need to ensure it’s the correct patient.
   d. Need to involve all staff in the process.
   e. Perform Team Time Out immediately before patient enters the angio suite.

Answer 8

e. Perform Team Time Out immediately before patient enters the angio suite. F

“Time Out” must be conducted in the room where the procedure will be done, which will usually be after sedation/anaesthesia. Should also check “immediately before entering the room in which the procedure will occur, or as soon as practicable after entering the procedural room but prior to the commencement of the anaesthesia/sedation”

Question 9

washing hands protocol. When not critical.

a. when leaving patient room
b. before procedure.
c. before examining a patient.
d. afer examining a patient.

Answer 9

A = F – only if you’ve touched the patient or their surroundings

B = T

C = T – before touching a patient

D = T – after touching a patient

Question 10

Patient with hives. Rash. Itchy. Not achy. Not hypo post IV contrast. What next.

a. IV 1: 1000 adrenalin
b. IM 1:1000 adrenalin
c. IV antihistamine
d. oral antihistamine

Answer 10

ANS = D (oral antihistamine) → mild reaction (urticaria)

Question 11

patient post IV contrast for CT chest crashes. CT shows air embolus. Which is not part of management.

a. left lat decubitus.
b. trendelenberg.
c. high flow oxygen

Answer 11

All are part of management of venous air embolus.
Ohs: IV line- gas goes into Rt Atrium/Ventricle –> lungs (stroke if PFO, pulmonary AVM). Lie pt left side down (left lateral decub), so gas rises and trapped in non-dependant RV, away from RVOT.

Management of air embolism (UTD)
Aim to prevent the gas passing from the right heart into the pulmonary arteries. Prevention of further embolism

o Venous air embolism:
Left lateral decubitus position (Durant’s manoeuvre),
Trendelenburg (head down) or left lateral decubitus with head down

o Arterial air embolism:
flat supine • Restoration of circulation

o Chest compressions (if lateral decubitus didn’t help)
• Remove embolised air
o Can attempt to aspirate air if central line in place
o High-flow oxygen (increases resorption of embolised air) & avoid nitrous oxide
o Hyperbaric oxygen therapy if cardiopulmonary compromise or neurologic deficits

100% supplemental oxygen can be used to decrease the size of the bubbles by reducing their nitrogen content.

Question 12

Going to do a pancreatic biopsy. Best bleeding profile

a. INR 1.3 Plt 90k, eGFR 45
b. INR 1.6. Plt 50k. Hb 8.5 eGFR 70
c. INR 1.7. Plt 90k. Hb 7.5 eGFR 35

Answer 12

Of course A

Platelets should replaced if <50,000.
INR should be corrected if above 1.5 in moderate to high risk procedures (Biopsies, angiography etc) and above 2.0 if low risk procedures (central lines, drainages etc.)
eGFR is an independent risk factor in that pts with poor renal function have platelet dysfunction. (Patients with renal impairment usually have abnormalities of platelet function).

According to one small study, patients with end stage renal failure on haemodialysis are at high risk (up to 50%) of haemorrhagic complications after percutaneous liver biopsy, independent of the bleed time - Gut 1999;45:IV1-IV11 doi:10.1136/gut.45.2008.iv1 Guidelines on the use of liver biopsy in clinical practice A Grant, J Neuberger)

Consensus guidelines from the Interventional society of Europe don’t include eGFR in there pre-procedure workup. Also noted that whilst platelet dysfunction is probably more important than platelet number in time to haemostasis – the difference in clinical practice is likely negligible.

Question 13

1) 25yo male. BP 90/60, Pulse 50 following IV contrast administration on angio table. No hives/urticaria. First line of treatment:
i) Adrenaline 1:1000 iv
ii) Adrenaline 1:1000 im
iii) Hydrocortisone iv
iv) Lower legs
v) Raise legs

Answer 13

v) Raise legs T

RANZCR guideline for vasovagal- raise leg- oxygen- atropine 0.6-1mg IV repeat 3-5min if necessary (total 3mg)

Question 14

2) Handwashing (no, really). Which of the following 5 options is NOT one of the recommended 5
i) Before touching a patient
ii) After touching a patient
iii) After touching a patients surroundings
iv) On leaving patients area
v) Before a procedure
vi) The reason we chose radiology in the first place was so we didn’t have to touch patients (we added this option ☺ )

Answer 14

iv) On leaving patients area

Question 15

3) Radiology events register (RaER):
i) Uses an Online web based entry system
ii) Something about near misses
iii) Can only be accessed by consultant radiologists
iv) Something about epidemiological data

Answer 15

i) Uses an Online web based entry system T

3) Radiology events register (RaER):
i) Uses an Online web based entry system T
ii) Something about near misses
iii) Can only be accessed by consultant radiologists F “Radiologists, radiographers and other disciplines involved in medical imaging are encouraged to report an incident anonymously into RaER.”
iv) Something about epidemiological data

Question 16

4) 50yo female for needs contrast enhanced CT C/A/P. Acute renal insufficiency with Cr 2x normal. Best option:
i) Pre hydration and Posthydration
ii) NAC
iii) Sodium Bicarb
iv) Use Gadolinium for contrast

Answer 16

i) Pre hydration and Posthydration T 100mL/hr for 6 hours before & 6 hours after contrast – however, better option would be to delay scan if not urgent (esp. as acute renal impairment), or consider non-contrast
* LW agrees

CT.4) 50yo female needs contrast enhanced CT C/A/P. Acute renal insufficiency with Cr 2x normal. Best option: from RANZCR guidelinesi) Pre hydration and Posthydration T 100mL/hr for 6 hours before & 6 hours after contrast – however, better option would be to delay scan if not urgent (esp. as acute renal impairment), or consider non-contrast CT.ii) NAC F “… the evidence is not convincing”iii) Sodium Bicarb Fiv) Use Gadolinium for contrast F “Do not use MRI contrast agents for CT or conventional angiography in an attempt to avoid nephrotoxicity.”

Question 17

A colleague shows you a Chest X-ray on which you are dismayed to find that you have missed a lung lesion the previous week. With regards to reporting which of the following is true? (Not sure if I recalled the stems correctly)

a. Day to day intra-observer variability radiology reporting varies between 2 to 3 % (3-5 %)
b. Interpretive errors make only a small percentage (less than 15 %) of litigation
c. Perceptual errors are less common than interpretive errors. (or interpretation errors are more common than perception errors)
d. Daily error rate varies between 5-10 %
e. Inter- and intra-observer variability varies between 5-10 %
f. Interobserver variability 1-5%

Answer 17

b. Interpretive errors make only a small percentage (less than 15 %) of litigation T In the USA, missed diagnosis (i.e. perceptual error) is the most frequent cause of radiology malpractice litigation

A colleague shows you a Chest X-ray on which you are dismayed to find that you have missed a lung lesion the previous week. With regards to reporting which of the following is true? (Not sure if I recalled the stems correctly)

a. Day to day intra-observer variability radiology reporting varies between 2 to 3 % (3-5 %) ??
b. Interpretive errors make only a small percentage (less than 15 %) of litigation T In the USA, missed diagnosis (i.e. perceptual error) is the most frequent cause of radiology malpractice litigation
c. Perceptual errors are less common than interpretive errors. (or interpretation errors are more common than perception errors) F more common
d. Daily error rate varies between 5-10 %
e. Inter- and intra-observer variability varies between 5-10 % F TB CXR study showed interobserver variability of 10-20%
f. Interobserver variability 1-5% F TB CXR study showed interobserver variability of 10-20%

JMIRO 2006 & 2011 (Pitman)
• Errors in diagnostic radiology comprise perceptual errors, which are a failure of detection, and interpretation errors, which are errors of diagnosis.
• Interobserver agreement in diagnostic interpretation of screening mammograms has been quoted as 78%, whereas intraobserver agreement in diagnostic interpretations of mammograms has been quoted as higher, at 84%
• Perceptual error rates of radiologists ≈ 30% (AJR 00)
• Approximately 4% of radiologic interpretations rendered by radiologists in their daily practice contain errors (AJR 07)

Question 18

Patient develops a contrast reaction (post IV contrast for CT A/P) with hives, lip and tongue swelling, dyspnoea and stridor etc. Best treatment is:

a. Adrenaline 1:1000 IV
b. Adrenaline 1:1000 IM
c. Hydrocortisone PO
d. Hydrocortisone IV
e. Raise legs
f. Antihistamine

Answer 18

b. Adrenaline 1:1000 IM T

Patient develops a contrast reaction (post IV contrast for CT A/P) with hives, lip and tongue swelling, dyspnoea and stridor etc best treatment is:

a. Adrenaline 1:1000 IV F (if give IV give 1 in 10,000)
b. Adrenaline 1:1000 IM T
c. Hydrocortisone PO F
d. Hydrocortisone IV F but still give IV hydrocortisone
e. Raise legs F but may do this
f. Antihistamine F

Question 19

IV contrast reaction. Which is most correct?

a. Antibody-mediated reaction.
b. Death in 1 in 80,000 (or “death rate < 1 in 80,000 with non-ionic contrast”)
c. Prophylactic steroids more likely to prevent major than minor adverse reactions (or “steroids prevent major complication”)
d. Prophylactic steroids should be commenced 4 hours prior to scan
e. Isolated shellfish allergy is an absolute contraindication to contrast (or “seafood allergy is a contraindication”)

Answer 19

b. Death in 1 in 80,000 (or “death rate < 1 in 80,000 with non-ionic contrast”) ? T risk of death is rare, 1 in 170,000 (RANZCR guideline)

IV contrast reaction. Which is most correct? (SK)

a. Antibody-mediated reaction. F Presents identical to an anaphylactic reaction, however considered an anaphylactoid or non-allergic anaphylactic reaction since an antigen-antibody response has not been identified in most reacting patients (ACR guidelines). Non IgE mediated, possibly by direct activation of mast cells & complement (UTD).
b. Death in 1 in 80,000 (or “death rate < 1 in 80,000 with non-ionic contrast”) ? T risk of death is rare, 1 in 170,000 (RANZCR guideline)
c. Prophylactic steroids more likely to prevent major than minor adverse reactions (or “steroids prevent major complication”) F … it is effective in preventing only minor adverse events. Prospective studies of pre-treatment have been too small to be able to determine whether pre-treatment with steroids prevents the life-threatening reactions (RG 04 & ACR guidelines)
d. Prophylactic steroids should be commenced 4 hours prior to scan F take at 13 hours and 1 hour before (RANZCR guideline)
e. Isolated shellfish allergy is an absolute contraindication to contrast (or “seafood allergy is a contraindication”) F Shellfish allergy is not associated with an increased risk of adverse reaction to intravenous iodinated contrast agents, over and above the 3-fold increased risk associated with other food allergies (RANZCR guideline)

Question 20

(Elderly) Patient for pancreatic (head) biopsy on clopidogrel, clexane and metformin. Normal renal function. What to stop and when

a. Clopidogrel for 10 days + clexane for 12 hours
b. Clexane for 10 days + clopidogrel for 12 hours
c. Clopidogrel for 10 days + metformin for 2 days
d. (various combinations)

Answer 20

a. Clopidogrel for 10 days + clexane for 12 hours
AJR 2009
• Clopidogrel stopped 3-5 days pre-op if safe to do so
• Enoxaparin (LMHW, Clexane) stop 12 hrs before procedureRANZCR
• Metformin stopped 48hrs before IV contrast if have renal impairment. Reassess renal function prior to recommencing.

Question 21

Open disclosure. Injected wrong side of the joint with steroid. What should you do.

a. Full explanation to pt re events
b. Delay talking to patient until discussion with Risk Management Officer
c. Full documentation on medical notes but not talk to patient directly
d. Not talk to patient as no complication
e. Talk first to referrer before discussing.

Answer 21

a. Full explanation to pt re events T Management of adverse events – open disclosure (RANZCR Patient Safety Syllabus)
• Advise supervisor immediately
• Documentation – health care records, incident reports
• Inform patient, demonstrate empathy
• Adverse events registerOpen Disclosure Standard (Australian Commission on Safety and Quality in Health Care):Open disclosure is the open discussion of incidents that result in harm to a patient while receiving health care.
The elements of open disclosure are:
• an expression of regret (as early as possible, the patient & their support person should receive an expression of regret for any harm that resulted from an adverse event),
• a factual explanation of what happened,
• the potential consequences,
• and the steps being taken to manage the event and prevent recurrence.

Question 22

Paper request for CT for liver lesion. Pt says he’s for elective hernia operation and does not have liver lesion. Checked request that the correct pt was brought to dept. a. Wrong pt sticker on the paper request b. Porter brought wrong patient down c. Wrong pt ID band d. Pt is confused e. Patient in denial.

Answer 22

a. Wrong pt sticker on the paper request

Question 23

1. 68yo man, chronic diabetes referred for CECT for ?PE. Known hypertension and hyperlipidemia. eGFR estimated at 20ml/min. Which of the following methods is most appropriate to reduce his risk of contrast induced nephropathy?
   a. Prehydration and pretreated with IV N-acetylcystine
   b. Use a nonionic monomeric contrast agent
   c. Use a nonionic dimeric contrast agent
   d. He should be pretrated with N-acetylcysteine
   e. Prehydration and pretrated with IV sodium bicarbonate

Answer 23

*LW:
My preferred option is C:

Based on the following points.
RANCR guidelines:
R8: In patients with severe renal function impairment (eGFR less than 30 ml/min/1.73m2
) or actively deteriorating renal function (acute kidney injury) careful weighing of the risk
versus the benefit of iodinated contrast media administration needs to be undertaken.
Consideration should be given to periprocedural renal protection using intravenous
hydration with 0.9% saline (see relevant section). However, severe renal function
impairment should not be regarded as an absolute contraindication to medically indicated
iodinated contrast media administration.

R15. For patients who are at higher risk of CI- AKI, pre and post procedural 0.9% IV saline is
recommended as the first line preventive strategy to mitigate the risk of CI-AKI.
R16. The evidence in support of the additional benefit of N – acetyl cysteine and/or sodium
bicarbonate alone or in combination with intravenous 0.9% saline is mixed and currently
these additional measures are not recommended due to additional expense and
complexity without clear evidence of incremental risk reduction. –> this implies no evidence for option A or option D or option E.

RANZCR says to use an iso-osmolar (dimeric, e.g. Visipaque) or low-osmolar (monomeric, e.g. Omnipaque) contrast agent. Avoid high-osmolar (ionic) contrast agents in renal patients. NB. Dimeric non-ionic agents do not have an advantage over monomeric contrast media with respect to CIN.

Previous answer:
a. Prehydration and pretreated with IV N-acetylcystine

1. 68yo man, chronic diabetes referred for CECT for ?PE. Known hypertension and hyperlipidemia. eGFR estimated at 20ml/min. Which of the following methods is most appropriate to reduce his risk of contrast induced nephropathy?
   a. Prehydration and pretreated with IV N-acetylcystine
   b. Use a nonionic monomeric contrast agent T? see option c
   c. Use a nonionic dimeric contrast agent T? RANZCR says to use an iso-osmolar (dimeric, e.g. Visipaque) or low-osmolar (monomeric, e.g. Omnipaque) contrast agent. Avoid high-osmolar (ionic) contrast agents in renal patients. NB. Dimeric non-ionic agents do not have an advantage over monomeric contrast media with respect to CIN.
   d. He should be pretrated with N-acetylcysteine F RANZCR states “Consider use of NAC”. Current evidence not convincing

.e. Prehydration and pretrated with IV sodium bicarbonateNew RANZCR guideline does not use NAC-> currently not recommended due to cost and no clear evidence of risk reduction

RecommendationsR4.
Intravascular iodinated contrast media should be given to any patient regardless of renal function status if the perceived diagnostic benefit to the patient, in the opinion of the radiologist and the referrer, justifies this administration.
R5. Emergency imaging procedures requiring contrast media administration e.g. acute stroke, acute bleeding, trauma etc. should not be delayed in order to obtain renal function testing results prior to the procedure.
R6. The risk of intravenous contrast media related acute kidney injury (CI-AKI) is likely to be non-existent for patients with eGFR greater than 45 mL/min/1.73m
2.No special precautions are recommended in this group prior to or following intravenous administration of iodinated contrast media.
R7. The risk is of intravenous CI-AKI is also very likely to be low or non-existent for patients with eGFR 30 - 45 mL/min/1.73m2. Universal use of periprocedural hydration in this group to prevent the theoretical risk of CI-AKI cannot be recommended but patients with impaired function in this range that is acutely deteriorating rather than stable may benefit from this intervention.
R8. In patients with severe renal function impairment (eGFR less than 30 ml/min/1.73m2) or actively deteriorating renal function (acute kidney injury) careful weighing of the risk versus the benefit of iodinated contrast media administration needs to be undertaken. Consideration should be given to periprocedural renal protection using intravenous hydration with 0.9% saline (see relevant section). However, severe renal function impairment should not be regarded as an absolute contraindication to medically indicated iodinated contrast media administration.

Question 24

2. 80yo man with diabetes referred for contrast MRI for Ix of recent onset seizures. He has hyperparathyroidism and hyperlipidemia. eGFR is estimated at 29ml/min. Which of the following options to reduce the risk of NSF is most appropriate?
   a. Haemodialysis immediately after the examination, and again within 24h.
   b. Use a linear chelate Gd contrast agent
   c. Use a monomeric Gd contrast agent
   d. Use a macrocyclic Gd contrast agent
   e. He should not receive any MRI contrast agent

Answer 24

**LJS - use macrocyclic. GFR 29 is considered low risk (egfr 15-30), not in the highest-risk-avoid-contrast group (GFR < 15ml)

https://www.ranzcr.com/college/document-library/gadolinium-containing-mri-contrast-agents-guidelines

Ohs:
In general, chelates with:
- cyclic structure (gadoterate, gadoteridol, gadobutrol) are more stable than
- linear molecules (gadobenate, gadopentetate, gadodiamide, and gadoversetamide).
*Gadodiamide and gadoversetamide are less stable chelates than the other linear agents.

Hemodialysis pt- then contrast pre dialysis, then dialyse 24 hrs again

Highest risk of NSF = Peritoneal dialysis. Avoid contrast, organise hemodialysis if possible, or more often peritoneal dialysis 48hrs. If benefit > risk, then use lower risk contrast (macrocyclic or gadobenate).