Liver Flashcards
Why do we want to be careful with our opioid use in liver disease?
Risk for sphincter of Oddi spasm
Sphincter of Oddi spasm will happen in about __% of the population given opioids
3%
Is there any way to predict who will experience sphincter of Oddi spasm?
No.
How can we antagonize sphincter od Oddi spasm?
Glucagon (.3mg up to 3 times) - can cause hyperglycemia and vomiting NTG (10mcg/min) - good for those with heart failure Naloxone (Narcan) - Will reverse the analgesic effect and have a bunch of other SE Nubain
What is the incidence for halothan hepatitis?
1: 10,000-30,000
This IA doesn’t cause hepatitis and why?
Sevoflurane does not undergo metabolism to trifluoroacetylated metabolites and is therefore not expected to produce immune-mediated hepatotoxicity or to cause cross-sensitivity
Reasons for post-op hepatic dysfunction
o Multi-factorial
o Review all drugs administered
o Check for sepsis
o Evaluate the possibility of increased bilirubin
o Rule out occult hematomas → hyperbilirubinemia
o Review peri-operative record for hypotension, hypoventilation, hypoxemia, hypercarbia, and hypovolemia***
This is the most common blood borne pathogen in the US
Hep C
HEV is transmitted via this route and in locations
Transmitted enterically
Asia, Africa, and Central America
In viral hepatitis, AST/ALT values may be as high as
400-4,000
Treatment for Hepatitis B
Interferon, Lamivudine, Adefovir (these will affect what drugs we use
Treatment for Hepatitis C
Interferon and Ribavirin
Treatment for autoimmune hepatitis
Corticosteroids and AZT
Cirrhosis is most commonly due to
HepC and ETOH abuse
The hepatic artery and portal vein both supply 50% of O2 each, but ____ provides 75% of total blood flow and ____ provides 25% of total blood flow
Hepatic artery = 25%
Portal vein = 75%
The liver is the site of synthesis of all clotting factors except
vWF
Patients with cirrhosis will have hyperdynamic circulation. What does this mean?
High CO
Low SVR
S/S of cirrhosis
o Fatigue /malaise o Anorexia/ weakness o Nausea/ vomiting o Abdominal pain o Jaundice /spider nevi o Hypoalbuminemia o Coagulation disorders o Endocrine disorders o Hepatic encephalopathy o Gastroesophageal variceal o Hepatomegaly /ascites
Many alcoholics can get cardiomyopathy. How does this affect your anesthetic?
Don’t give anything that depressed the myocardium
How do the majority of cirrhosis patients die during abdominal surgery?
60% die from bleeding
In cirrhosis, these clotting factors are deficient, and it results in these decreased lab values
Factors 2, 5, 7, 9, 10
Vitamin K
Low platelet count
Prolonged PT and INR
These bleeding values are contraindications to elective surgery
Plts 3 sec
Treatment for cirrhosis induced coagulopathy
FFP
- Give 10-20mL/kg
- Contains all clotting factors, but will only last for 12-24 hours
Vitamin K (if malnutrition is present)
Platelets (give prophylactically for those
We must avoid this monitoring in cirrhosis patients!
Esophageal temp probe!
Monitoring we want for cirrhosis patients!
Invasive monitoring (CVP, a-line)
PA Cath if severe cardiomyopathy
Always be checking blood glucose
Foley catheter for UO
Why are cirrhosis patients considered full stomachs?
Alcohol use weakens the lower esophageal sphincter
Liver patients tend to be (hyper/hypo)glycemic
Hypoglycemic. Give fluids with glucose
Pts are hypoglycemic d/t decreased hepatic gluconeogenesis.
How should we maintain anesthesia for the patient with cirrhosis?
IA at 1/2 MAC with N2O and opioids
In cirrhosis, we need a (higher/lower) dose of NMRs and why?
Need higher dose because Vd will be increased
What NMBs are best for cirrhosis
Mivacurium, atracurium, cisatracurium*
(the ones metabolized in blood)
Sux is apparently ok too
Reasons why liver patients are at risk for morbidities post-op
Pneumonia Bleeding Sepsis Poor wound healing Liver dysfunction DT’s
Within __-__ hours from alcohol withdrawal, the patient may become tremulous
6-8
Alcohol hallucinations and grand mal seizures occur within __ hours after a patient’s last drink
24
DTs usually appear within __ hours of withdrawal and are preceded by _______
72
tremulousness, hallucinations or seizures
What is the treatment for DTs?
Benzos
Give these up front
Other comorbidities that alcoholics may have
Hypothermia, alcoholic poluneuropathy , Wernicke-Korsakoff syndrome, Pernicious anemia
Overall considerations for the maintenance phase of anesthesia
No IAs with bad effects on the liver (no decrease in hepatic BF or risk of hepatitis).
- Stick to sevo*, iso, and des
Maintain BP to ensure adequate hepatic BF
Use NMBs that are metabolized in the blood (miv, atra, cisatra, sux)
Maintain with IA at 1/2 MAC with N2O and opioids
Don’t give anything that will depress the heart!
Patients will have low protein binding
Bleeding risk
Considered full stomachs (poor lower esophageal sphincter tone)
Give fluids that contain glucose
Why the fuck is porphyria listen again in the liver ppt?
Because people with liver problems can develop porphyria even without a genetic predisposition (probably lack of enzyme formation by the liver)
This enzyme is deficient in porphyria
ALA synthetase
A purple/blue case of _____ is associate with porphyria
urine and feces
Triggers for porphyria crisis
Enzyme inducing drugs, other drugs (BAD SENK), hormonal fluctuations (menstruation, fasting, dehydration, stress, infection)
S/S of porphyria attack
abd pain, N/V, ANS instability (HTN and tachycardia), electorlyte (Na, K, MG) disturbances, neuro psych manifestations, weakness.
Weakness can progress to quadriparesis and respiratory failure.
Treatment for porphyria
Hematin 3-4mg/kg (drug of choice) Remove triggering agents Hydration Carbohydrates (b/c a trigger is fasting) Treat pain and N/V Beta blockers for HTN & tachycardia Benzodiazepines for seizures Fluid and electrolyte balance
When is regional anesthesia not a good choice in porphyria?
During an acute exacerbation
Should a patient going for a cholecystectomy be intubated with a RSI?
Yes, because the patient may have ileus or have been vomiting and will be high aspiration risk
Why do patients have hyperdynamic circulation with liver disease?
Accumulation of vasodilating compounds like prostaglandins and interleukins.
Reduced blood viscosity may also play a role.
Any IAs that decrease hepatic BF will increase serum concentrations of
Alpha-GST
Blood volume in liver disease
Decreased in central circulation, but increased in splanchnic circulation, pulmonary, muscle, and cutaneous as well.
GA Considerations in porphyria
- Use short acting agents
- Monitor for instability
- Induction
- Propofol, ketamine → these are ok to use in porphyria
- Maintenance
- Nitrous, inhaled anesthetics, opioids, NDMR
- CP bypass a stress
RA considerations in porphyria
- No contraindication
- Pre anesthetic neuro evaluation (any numbness or tingling?)
- CV instability d/t sympathectomy, ANS neuropathy, hypovolemia
- Not best choice during acute exacerbation**
Is cimetidine good or bad in porphyria?
GOOD. It decreases heme consumption and decreases ALA synthetase activity.
These meds can be given to treat porphyria
Hematin 3-4 mg/kg IV, somatostatin, plasmapheresis
