Organ Donation/Transplant Flashcards
Maximum ischemic cold times
Heart and Lungs
Liver
Kidneys
Heart and Lungs 4-6 hrs
Liver 12-24 hrs
Kidneys 72 hrs
What is the most common method for donation?
Brain death organ donors
What is the definition of brain death
irreversible cessation of circulatory and respiratory functions, or of all functions of the entire brain, including the brain stem.
d/t lack of blood supply and O2
T/F: An individual’s signature on a driver’s license or donor card indicating their desire to donate their organs is legally binding and does not require family permission.
TRUE
Criteria for the diagnosis of brain death
Loss of cerebral cortical function
- no spontaneous movement
- unresponsive to external stimuli
Loss of brainstem function
- apnea
- absent CN reflexes (papillary, corneal, oculocephalic, oculovestibular)
Supporting documentation
- EEG
- cerebral blood flow studies
Common physiological derangements after brain death
Hypotension (DI, hemorrhage, neurogenic shock), arterial hypoxemia, hypothermia, cardiac dysrhythmias
Donation after cardiac death (DCD): Non-heart-beating donors Severe whole brain \_\_\_\_\_\_ Have \_\_\_\_\_\_ in the brain Death is defined by cessation of \_\_\_\_\_
dysfunction
electrical activity
circulation and respiration.
T/F: DCD –> Life support measures are used to control the timing of death, organ procurement, and to maximize function of organs from these donors.
TRUE
in DCD, after the patient’s heart stops beating, the physician declares death. The transplant
team waits no less than 5 minutes following
pulselessness before starting organ recovery.
Which organs can often be recovered?
The lungs, liver, pancreas and kidneys often
can be recovered.
Anesthesia management is _____ for organ donation after brain death. (DBD)
Anesthesia management _____ for organ donation after cardiac death. (DCD)
required
MAY NOT be required
in organ recovery, how many surgeons will scrub in?
2
Anesthesia support of donor organ systems is necessary until
the proximal aorta is clamped, after which the ventilator, IV’s, and cardiac monitors may be discontinued.
after cross-clamp, you will be dismissed
If lungs are being transplants, anesthesia support will be required after cross-clamp. Why?
The purpose is to hyperventilate the lungs to insure that the perfusion is delivered at the cellular level. At this point you may be asked to extubate so the lungs and trachea may be recovered
The recovery of viable organs is dependent upon adequate respiratory support and organ perfusion as indicated by a:
BP ____ systolic and/or CVP ____
Maintain O2 sat ____ and urine output ____
SBP >100 and/or CVP 8-10
O2 sats >96%
UOP > 100 cc/hr
Vigorous volume expansion with crystalloid and colloid is usually necessary to avoid hypotension. What is the goal?
Euvolemia should be goal.
Anesthesia for organ procurement:
No anesthesia is necessary but a muscle relaxant may be required, why?
to neutralize spinal reflexes and relax the abdomen
Living donors account for ___% of all donors. They are frequently _____ to the recipient. Between the ages of ____. With no hx of…
44%
related
18-60
HTN, DM, CA, kidney or heart disease
Frequently required drugs and fluids for organ recovery
6-8 Lactated Ringers Heparin 30,000 units Thyroxin drip may be required in certain cases Pancuronium/Vecuronium dopamine, NEO, LEVO, or vasopressin
What is on hold for extra renal donors
PRBCs
What must be available if the liver is being split?
two (or more) units of PRBC’s are REQUIRED in the OR
Absolute contraindications to organ transplant
Active uncontrolled infection AIDS Inability to tolerate immune suppression Severe cardiopulmonary/medical condition - (patient unfit for surgery) Continued drug or alcohol abuse Extrahepatic Malignancy Inability to comply with medical regimen Lack of psychosocial support
What has caused the dramatic increase in the success of organ transplantation?
Immunosuppressive regimens
- Cyclosporine 1980s ~ decreased host rejection
- Azathioprine (Imuran)
- OKT3 (Muromonab-CD3)
- Steroids ~prednisone and methylprednisolone
Improved donor:recipient tissue typing
Post-transplantation organ function is dependent on multiple factors…
Donor demographics
Organ ischemic time
Mechanism of death of donor
Medical condition of recipient
Most frequent solid organ transplants
Kidney –25,500 Liver – 6,291 Heart – 3,000 Lung – 1,000 Heart-lung - 40
7000 kidney transplants are from _____
what is the 5 year survival rate?
cadavers
72% - nonextended criteria
57% - extended criteria
What is the remaining kidney donors from?
What is the 5 year survival rate?
living donors
81%
What is the 5 year survival on dialysis?
30%
What are the common indications for kidney transplant?
DM & HTN (most common)
Glomerulinephritis
Polycystic kidney disease
Physiologic disturbance often present before renal transplant
Peripheral neuropathy lethargy anemia platelet dysfunction pericarditis HTN Depressed EF Pleaural effusions skeletal muscle weakness ileus Glucose intolerance
What does HTN lead to?
LVH, cardiac chamber dilatation, increased Lt ventricular wall tension, redistribution of coronary blood flow, myocardial fibrosis, heart failure and arrhythmias.
What is anemia r/t in renal transplant patients? how does the body compensate?
decreased erythropoietin production and hemolysis
compensates by increasing CO –> ischemia
What may the HGB be in a renal transplant patient?
Hgb may be 5-8 g/dL. May need transfusion ahead of time, coagulopathies are prevalent, may need desmopressin or cryo.
For renal patients, a hgb of ____ is needed for adequate O2 delivery to the heart and transplanted graft
8% or greater
In renal patients, what is caused by diabetic autonomic neuropathy?
Can make intra-op BP control difficult
Gastroporesis - increasing risk for aspiration
What electrolyte abnormalities are common in renal patients?
Hyperphosphatemia is common, leads to hypocalcemia due to lack of calcium absorption due to inability to activate Vit. D = risk for fractures.
Hyperkalemia is most hazardous.
Why is airway assessment of pts with type 1 DM extra important?
These patients often manifest with stiff joint syndrom characterized by a fixation of the atlantooccipital joint along with limited head extension
What respiratory issues may type 1 diabetics have?
Pulmonary function impairment is related to a loss of lung elastic properties and is characterized by a decrease in cough reactivity, a significant restriction of lung volumes with a reduced tidal volume and forced expired ventilation (FEV)
What is the fluid protocol for a living kidney donor
10mL/kg/hr ABOVE calculated losses
Maintain UO > 100mL/hr.
Titrate to a specific CVP (can be inaccurate)
Why should you NOT use nitrous during kidney transplant
distended bowel can get in surgeons way (laparoscopic)
Cadeveric kidney transplant:
Patient is positioned supine. After induction of anesthesia, a _____ is placed. Incision in the right or left lower quadrant. The retroperitoneal space is developed by retracting the peritoneum. The _____ are identified. The vein is clamped and anastomosed first followed by the artery, then clamps are released. ____ should be given by this point. The bladder is filled with ____ to facilitate implantation of the ureter.
3-way Foley
retracting the peritoneum
external iliac vein and artery
Mannitol or Lasix
antibiotic solution
What lines should the renal transplant patient have?
- 2nd IV
- Aline
- CVP (The accuracy of CVP to monitor Lt ventricle pre-load status is still debatable)
- PAC is necessary to monitor CO, SVO2 and pulmonary arterial and capillary pressures.
Be attentive to hypotension after reperfusion of donor kidney because graft function is critically dependent on perfusion pressure.
!!!
What drugs should be AVOIDED in the kidney recipient?
alpha adrenergic drugs because transplanted kidney is sensitive to sympathomimetics.
(this will compromise blood flow to the kidney)
What IVF is contraindicated in RT patients
LR
Muscle relaxant based off K level:
normokalemic:
Hyperkalemic:
normokalemic –> Succs (1-1.5 mg.kg)
otherwise –> cisatracurium (0.1 mg/kg) or mivacurium (0.15-0.2 mg/kg) is preferable.
When are DMR preferred to intubate a renal patient
pts who are at high risk of pulmonary aspiration as in ESRD d/t autonomic gastropathy, obesity, or on peritoneal dialysis with significant volume of dialysate fluid left in
What reversal meds do you use with kidney transplant
Neostigmine and robinul is safe in patients with ESRD
Is propofol safe in renal transplant?
yes, metabolized by the liver
If diabetic gastroporsis is a concern, what should you give?
(Sodium citrate and citric acid oral solution 30 mL) is administered immediately prior to the induction of anesthesia to decrease the gastric acid content
Use of metoclopramide (30 mg PO) may increase gastric emptying and lower esophageal sphincter tone
Administration of an H2 blocker 6-12 hours prior to induction can decrease gastric acid production
The use of continuous epidural analgesia may be considered for intraoperative as well as postoperative pain control. Low dose local anesthetics and narcotics (bupivacaine 0.125% and fentanyl 3mcg/ml). What needs to be considered
coagulopathies
Why should analgesics be used cautiously prior to surgery?
Active metabolites
Morphine:morphine-6-glucuronide, Meperidine:normeperidine
Vasopressors or positive inptropes may be needed to increase cardiac output and renal perfusion pressure. What are the meds?
Dopamine
Fenoldopam
Norepinephrine
Vasopressin
When do you give mannitol and loop diuretics?
Before unclamping vascular supply to transplanted kidney
Reperfusion of the kidney graft may be associated with hypotension. This is most often related to a reduction in the preload as a consequence of unclamping the iliac artery. What should this be treated with?
Treat with crystalloid, colloid or low-dose dopamine
Significance of decreased urine output
May indicate mechanical impingement of graft, anastamosing vessel, or ureter.
Intra-operative ultrasound may be used to assess flow through arterial and venous anastamosis.
Moderate to severe hypertension may accompany emergence from anesthesia for renal transplant. What meds should be used and avoided?
Short-acting anti-hypertensives may be considered
The use of longer acting beta-blockers should be avoided as they may raise K+ levels
Anesthetic considerations for a patient with prior renal transplant surgery
Renal excretion of drugs is usually decreased compared to those with native kidneys.
Patients still suffer from primary systemic disease –DM, HTN
Avoid muscle relaxants that rely on renal excretion for elimination
Provide adequate hydration
Avoid hypotension
10 year survival rate for liver transplant
~60%
Indications for liver transplant
Cholestatic disease
- Primary/secondary biliary cirrhosis
- Sclerosing cholangitis
- Biliary atresia
- Cystic fibrosis
Metabolic diseases
Malignant disease of liver
- Hepatocellular carcinoma
- Carcinoid tumor islet cell tumor
- Epithelioid hemangioendothelioma
End stage liver disease
Acute hepatic necrosis
- Viral hepatitis
- Drug toxicity
- Toxins
- Wilson’s disease
Chronic Hepatitis
- B, C, D
- Autoimmune hepatitis
- Chronic drug toxicity
- Cryptogenic cirrhosis
Post necrotic (non alcoholic) cirrhosis
Sclerosing cholangitis
Alcoholic cirrhosis may be considered for transplant if abstinence of alcohol for
6 months
What is Wilsons disease?
rare genetic disorder that does not allow for the body to eliminate copper causing it to build up in key organs
Most livers available for transplantation come from _______ donors.
heart-beating cadaveric
A heart-beating cadaver is kept alive in order to keep its organs from decaying before they can be transplanted…some donated organs are taken from non-heart-beating donors. Organs from brain deaths, however, have a better success rate, and currently most organ donation is from these deaths.
Pt’s. with chronic liver dysfunction and cirrhosis have a ________ circulation with low ________ and an increased _____
hyperdynamic
peripheral vascular resistance
cardiac index
T/F: Coagulopathies, edema, ascites, renal dysfunction, portopulmonary hypertension, hepatopulmonary syndrome, and autonomic neuropathies are common in chronic liver dysfunction
True
Hepatic encephalopathy is thought to be multifactorial, resembles and must be differentiated from many other nonfocal neurologic conditions such as
hypoglycemia, hyponatremia, intracranial hemorrhage or mass lesions, and meningitis.
Co-morbid conditions associated with liver failure
look at slide 57! but some important ones are Increased ICP Anemia Thrombocytopenia Prolonged PT/PTT Decreased plasma fibrinogen DIC Protein C&S deficiency Hypokalemia and Hypocalcemia Metabolic acidosis
How is the incision for liver transplant?
Large subcostal incisoin
painful and large potential for hemorrhage
What does orthotopic mean?
the native liver is removed and replaced by the donor organ in the same anatomic position as the original liver
Considerations for anesthetic drugs for liver transplant
Rely on hepatic metabolism and excretion
Use is safe due to implantation of functioning liver
Do you use nitrous on a liver transplant?
NO
What is the pre-anhepatic phase?
Lysis of adhesions and exploration of abdomen
Mobilization of liver and careful dissection of hepatic artery, common bile duct, supra and infra-hepatic vena cava & portal vein
What is a non-shunting procedure aimed at?
aimed at controlling hemorrhage from portosystemic varices.
What do shunting procedures do?
redirect the portal venous flow into the systemic venous circulation via a nonvariceal conduit, thus relieving portal hypertension, decompressing varices, and at the same time relieving ascites.
The pre-anhepatice phase is where what occurs
Coagulation problems ***
Why is there decreased venous return in the pre-anheptic phase?
from surgical retraction and IVC clamping
What are the electrolyte abnormalities in the pre-anhepatic phase?
Hypocalcemia, hyperkalemia, metabolic acidosis
Ascites is drained and patient can experience large fluid shifts. Decrease in intrabdominal pressure may show volume depletion. What do you use for volume expansion?
Volume expansion with 5% albumin
In the pre-anhepatic phase, what CVP should you maintain and why?
maintain low to low-normal CVP to decrease blood loss
What is the gold standard to guide transfusions?
TEG
takes 45 minutes
What is the anhepatic phase
Begins with clamping of hepatic blood flow
Removal of native liver
Implantation of donor liver
When a bicaval clamp (Clamp venacava above and below liver) is placed in the anheptic phase, what may you see?
Drop preload
Profound hypotension and tachycardia***
The piggyback technique side clamps the inferior vena cava, what is different compared to bicaval?
Preserves some caval flow and preload
T/F: In the anhepatic phase, Hemorrhage, increasing fibrinolysis, coagulopathy, acidosis, hypothermia and decreased renal function may occur
true
In the anhepatic phase, aggressively treat hypotension with fluids to CVP of
10-20 cm H20. No metabolism will lead to lactate build up and metabolic acidosis. Will worsen with reperfusion, so treat ahead of time. (Usually goal for higher CVP).
What does the neohepatic phase begin with?
Begins with unclamping of the portal vein, hepatic artery and vena cava and reperfusion of the donor liver
What is preparation for the neohepatic phase important
This is a period of great hemodynamic instability (post re-profusion syndrome)
May need potent vasopressors.
Epi, norepi, both
Fluid overload prior to unclamping should be avoided
Hemodynamics typically stabilize once allograft begins to function.
What is reprofusion syndrome?
Is characterized by decreased CO, HR and BP, conduction defects (bradyarrythmias, asystole), pulm HTN, and decreased SVR
A rapid increase in K+ can occur, ensure normal pH and electrolytes prior to unclamping
Severe coagulopathies occur d/t fibrinolysis, release of heparin and hypothermia
Initial indirect signs of functioning graft
- Intraoperative bile production
- Intraoperative spontaneous correction of negative base excess
- Improvement in coagulation
- Temp, glucose improvement
Are liver transplants extubated after?
NO
