Kidney and Liver Transplant Flashcards
What are the most common causes of end-stage renal disease?
- Diabetes
- Hypertension
- Glomerulonephritis
Kidney donor and recipients must have the same what? (hint: molecule)
HLA - human leukocyte antigen
What is known as a transplant that is placed in the same anatomic location as the native organ?
Orthotopic
In adults, where are renal transplants usually placed?
Rt iliac fossa
What is another term for a renal transplant from a deceased donor?
“Carrel patch” - the RA and a section of the Ao is anastomosed to the recipients EIA
What creates a higher chance of thrombosis in renal transplantation? A transplant from a living or deceased donor?
LIVING - because the anastomosis is smaller
What is an En-bloc transplant/what does the recipient receive?
Recipient will receive both kidneys, both ureters, both renal arteries with a section of the suprarenal AO and both renal veins with a section of the infrarenal IVC
SF of a transplanted kidney?
- Superficial and run with the axis of the incision site
- Hilum oriented inferior and posterior
T or F? A native kidney is typically smaller than a transplanted kidney?
TRUE
What is the normal RI of a transplanted kidney?
0.6-0.7
What 3 parameters would conclude a normal transplanted kidney?
- Low resistance waveform
- Sharp systolic upstroke with forward end-diastolic flow
- RI <0.7
What is the most common cause of graft loss in a renal transplant?
Rejection
What are the 3 types of rejection?
- Hyper-acute - Occurs minutes to hours after
- Acute - Occurs 2 weeks to 3 months. RI > 0.8
- Chronic - Gradual deterioration beginning 3 months after
What is ATN (acute tubular necrosis) caused by?
Cold ischemic time
What is known as the “time between chilling of organ after blood supply has been cut off and when it is warmed by having its blood supply restored” ?
Cold ischemic time
Is ATN more common in living or deceased donors?
Deceased
T or F? ATN is a sign of rejection?
FALSE
When does acute tubular necrosis typically occur?
Day 2 or 3 after operation
What substance may remain high, making it difficult to distinguish between ATN & rejection?
Creatinine
What is known as “hypertension secondary to extrinsic compression of the kidney by a subcapsular collection/hematoma”?
Page kidney
A hematoma after kidney transplant is typically seen in which pole of the kidney?
Lower pole
What are the different fluid collections seen in a kidney transplant?
- Hematoma - found immediately post-op
- Urinoma - suspected if urine output decreases but kidney is functioning normally
- Lymphocele - pseudo-cysts filled with lymph and has a hard fibrous capsule - SF will show septations within the cyst
T or F? Mild pelvocaliectasis is a normal finding in a transplanted kidney?
TRUE
Is renal artery thrombosis (RAT) more common in adult or peds with renal transplants?
Peds
When does renal vein thrombosis typically occur after renal transplant?
24-48 hours post-op
SF of RVT in renal transplant?
- enlarged kidney
- decreased renal cortical echogenicity
- enlarged main RV that contains low-level echoes
- absence of flow by color or power Doppler
- REVERSED diastolic flow in the renal ARTERIES
What is the particular patient presentation for renal artery stenosis after kidney transplant?
Patient presents 6 to 12 months post-op with refractory hypertension
SF of renal artery stenosis?
- PSV of greater than 250 cm/s
- renal artery-to-EIA ratio >2.0
- post-stenotic turbulence
- distal spectral broadening
Where does renal vein stenosis typically occur after renal transplant?
Near anastomosis site
SF of renal vein stenosis?
- color aliasing on color Doppler
- doubling or tripling of the velocities across the area of narrowing on spectral Doppler
In an AVF, arterial blood empties into venous connection. Does this cause a high or low resistance gradient?
Low
In AVF, what do the waveforms look like in the artery and vein?
Feeding artery - High PSV and EDV (low-resistance)
Vein - pulsatile, high velocity and resembles an arterial signal
What abnormality in the vessels after a renal transplant will appear as an “area of color aliasing and a soft tissue color bruit”?
AVF
What abnormality show an “area within the renal parenchyma, which will have flow on color Doppler and no connection with a vein”?
Pseudoaneurysm
What parameters must occur for treatment of a pseudoaneurysm (renal transplant)? How can it be treated?
- PSA is larger than 2 cm
- Expanding or extrarenal in location
Can be treated via embolization or stent exclusion
SF of pseudoenurysm?
- swirling color pattern (“yin-yang” sign) in PSA
- “to-and-fro” in neck of the PSA (flow toward PSA
during systole & away during diastole) - Color bruit may be seen
What are the most common causes for a liver transplant?
- Alcoholic liver disease
- HCC
- Hepatitis C
T or F? Liver transplants are always orthotopic whereas kidney transplants are not?
TRUE
What is the “piggy back” technique in liver transplantation?
The recipients IVC is left in place and the supra-hepatic portion of the donor’s IVC is then attached to the recipients hepatic vein confluence
During what ‘phase’ do surgeons remove the recipient’s native liver and gallbladder?
Anhepatic phase
Arterial anastomosis in a liver transplant is between what vessels in both the donor and recipient?
Donor’s celiac axis anastomosed with recipients CHA AT the GDA confluence
What is the term for “reconstruction of biliary tree” in liver transplants? The donor’s CBD is anastomosed to the recipients (what structure)?
Choledochocholedochostomy = FUCKING ABSURD
Donors CBD is anastomosed with recipients CHD
In a single liver lobe transplant, what side of the liver is usually given to adults vs children?
Rt lobe - given to adults
Lt lobe- given to children
T or F? Perihepatic fluid & right-sided pleural effusion is normal in early post-op after liver transplant?
TRUE
What are the most common causes of liver transplant loss?
- Rejection
- Biliary complications (associated with HA stenosis/occlusion)
- Vascular complications (detected by the presence, direction, and velocity of blood flow)
What is the most common & serious complication & can lead to biliary necrosis and loss of the transplant?
Hepatic Artery Thrombosis (HAT) - because the HA is the sole blood source to the bile ducts after liver transplantation
Hepatic Artery Thrombosis risk factors after liver transplant?
- Rejection
- Blood incompatibility
- Prolonged transport time of organ
What is a common patient presentation for hepatic artery stenosis in liver transplant?
- Elevated LFT’s
- Biliary ischemia
SF of hepatic artery stenosis in liver transplant?
- Aliasing at area of stenosis & a color bruit
- Velocity >200 to 300 cm/s
- Post-stenotic turbulence
- Tardus-parvus waveform in intraparenchymal HAs
What is known as the “abnormal dilatation of the hepatic artery found at the vascular anastomosis”?
Hepatic Artery pseudoaneurysm
SF of hepatic artery pseudoaneurysm?
- Anechoic mass w/ color-swirling pattern (“yin-yang” sign)
- To-and-fro flow waveform will be seen in the neck of the PSA
Patient presentation for PV thrombosis in liver transplantation?
- Early liver failure
- Portal hypertension
Acute vs chronic features of PV thrombosis?
Acute - PV may appear enlarged/distended
Chronic - PV may be contracted around the thrombus
What happens in the hepatic veins with supra-hepatic IVC stenosis?
Reversed flow or loss of phasicity in the HV’s
Which of the following is NOT a symptom of kidney graft failure?
a. elevated red blood count
b. fever and chills
c. elevated serum creatinine level
d. pain and tenderness
A
Where are kidney transplants most frequently placed?
a. normal kidney position
b. right iliac fossa position
c. left iliac fossa position
d. right posterior position
B
In a DD kidney transplant, which vessel anastomosis is performed?
a. Donor aortic wall and recipient external iliac artery
b. Donor aortic wall and recipient internal iliac artery
c. Recipient renal artery and donor external iliac artery
d. Recipient external iliac artery and donor main renal artery
A - AKA “carrel patch”
Which of the following is a renal transplant complication that is relatively common in the post-surgical period?
a. superinfection
b. urinoma
c. lymphocele
d. ureteral occlusion
C
What is the optimal time frame to perform a baseline sonogram in renal transplant patient?
a. 6 hours
b. 12 hours
c. 24 hours
d. 48 hours
D - 24-48 hours in the slides
How long after transplantation does the kidney reach maximal size?
a. 12 months
b. 6 months
c. 4 months
d. 2 months
B
Which sonographic image would best demonstrate the presence of a urinoma?
a. transverse superior to the kidney
b. sagittal at mid-kidney
c. transverse bladder
d. oblique view of lower pole of kidney and bladder
D
What is normal arterial RI in a transplanted kidney?
a. 0.5
b. 0.7
c. 0.9
d. 1.0
B - between 0.6-0.7 in slides
Which velocity is critical to accurately calculate the RI?
a. early diastolic
b. mid-diastolic
c. end diastolic
d. systolic
C
What pattern of color display in the interlobar arteries is consistent with normal flow?
a. flow with minimal diminishment at end diastole
b. lack of flow at end diastole
c. flashy and pulsatile
d. minimal flow at end diastole
A - because it’s a low resistance waveform
When does graft loss caused by rejection occur?
a. 3 months
b. 6 months
c. 9 months
d. 12 months
A
What is the medical term for sudden cessation of urine production?
a. anuria
b. oliguria
c. polyuria
d. hematuria
A
Which of the following is NOT a risk factor for development of ATN?
a. ischemic time
b. hypertension
c. donor illness
d. non-heart beating surgery
B
Which of the following best describes a perinephric fluid collection with multiple thin septations?
a. hematoma
b. urinoma
c. hydronephrosis
d. lymphocele
D
Which of the following best describes sonographic duplex findings consistent with renal artery thrombosis (RAT)?
a. anechoic lumen with low-resistance flow pattern
b. anechoic lumen with high-resistance flow pattern
c. intraluminal echoes with low-resistance flow pattern d. intraluminal echoes with absence of flow
D
With which of the following transplant complications does enlargement of the kidney with decreased renal cortical echogenicity most consistent?
a. renal artery thrombosis
b. renal vein thrombosis
c. renal artery stenosis
d. lymphocele
B
What is the most common vascular complication following renal transplantation?
a. renal artery thrombus
b. renal vein thrombus
c. renal artery stenosis
d. renal artery kink
C
What do Doppler criteria consistent with RAS of >50% to 60% in transplanted kidney include?
a. PSV >250 cm/s
b. PSV ratio ≤2.0 to 3.0
c. AT<70to80ms
d. lack of end-diastolic flow
A
Which of the following is NOT a Doppler characteristic of an AVF?
a. area of color aliasing
b. soft tissue color bruit
c. high velocity in both systole and diastole
d. low velocity in both systole and diastole
D
Which type of anastomosis is performed for the arterial anastomosis of hepatic artery in liver transplants?
a. end to end
b. side to side
c. fish mouth
d. piggy back
C - key word “arterial” anastomosis
Which of the following is the most common cause of liver transplant loss?
a. rejection
b. biliary complication
c. surgical technique
d. vascular cause
A
Which of the following is NOT a contraindication for liver transplantation?
a. renal malignancy
b. untreated infection
c. hemochromatosis
d. CHF and COPD
C
What is the preferred anastomosis of donor CBD?
a. common hepatic duct
b. common bile duct
c. duodenum
d. jejunum
A
What is the best patient “window” for sonographic duplex assessment of hepatic transplant?
a. infracostal
b. midline
c. subcostal
d. intercostal
D
What is the most common vascular complication of liver transplantation?
a. hepatic artery thrombosis
b. hepatic artery stenosis
c. hepatic artery pseudoaneurysm
d. portal vein thrombosis
A
A liver transplant patient presents to the vascular lab for evaluation after core needle biopsy. Which of the following would be a concern in this patient?
a. hepatic artery thrombosis
b. intrahepatic artery pseudoaneurysm
c. portal vein thrombosis
d. hepatic artery stenosis
B
Upon duplex evaluation of a recent liver transplant, tardus parvus waveforms are noted in the interparenchymal hepatic arteries. Which of the following would be a concern in this patient?
a. hepatic artery thrombosis
b. intrahepatic artery pseudoaneurysm
c. portal vein thrombosis
d. hepatic artery stenosis
D
What would be suspected in a liver transplant patient with signs of early liver failure and portal hypertension?
a. hepatic artery thrombosis
b. intrahepatic artery pseudoaneurysm
c. portal vein thrombosis
d. hepatic artery stenosis
C
A liver transplant patient presents to the vascular lab with worsening liver function. Upon duplex evaluation, velocities in the main portal vein reach 200 cm/s. What do these findings suggest?
a. portal vein stenosis
b. hepatic artery thrombosis
c. portal vein thrombosis
d. portal vein pseudoaneurysm
A
A liver transplant patient presents to the vascular lab for follow up. Upon questioning, the patient indicates he has been experiencing lower extremity swelling. Which of the following would be of concern to the vascular technologist?
a. portal vein thrombosis
b. hepatic artery thrombosis
c. inferior vena cava thrombosis
d. hepatic vein thrombosis
C
Hypercoagulable states, hypotension, intraoperative trauma, mismatch of vessel size, and vascular kinking are risk factors for (in terms of renal transplants) ?
Renal artery thrombosis
In liver transplantation, hepatic artery stenosis or occlusion is often associated with what pathology, owing to sole blood supply?
Biliary pathology
