Hepatobiliary and GI distrubances and Anesthesia Flashcards
The liver receives about ________of the cardiac output via a dual blood supply
The liver receives about 25% of the cardiac output (1,500 mL/min) via a dual blood supply
The portal vein provides____of the total liver blood flow and provides ____ of the liver’s oxygen supply.
The hepatic artery provides ___ of the total liver blood flow and provides ____ of the liver’s oxygen supply
The portal vein provides 75% of the total liver blood flow and provides 50% of the liver’s oxygen supply.
The hepatic artery provides 25% of the total liver blood flow and provides 50% of the liver’s oxygen supply
True or False: Portal blood flow is autoregulated, and decreased splanchnic vascular resistance reduces portal vein flow.
false
Portal blood flow is not autoregulated, and increased splanchnic vascular resistance reduces portal vein flow
When there’s a reduction in portal vein blood flow, the hepatic arterial buffer response compensates by ________ through the hepatic ________.
__________ impairs this response, making the diseased liver even more susceptible to hypoperfusion
When there’s a reduction in portal vein blood flow, the hepatic arterial buffer response compensates by increasing flow through the hepatic artery.
Severe liver disease impairs his response, making the diseased liver even more susceptible to hypoperfusion.
__________ and __________ anesthesia reduce _______ and _________.
This can reduce liver blood flow in a dose-dependent fashion.
Both general and neuraxial anesthesia reduces MAP and cardiac output.
This can reduce liver blood flow in a dose-dependent fashion.
Liver function
Protein synthesis
Drug biotransformation
Vital role in carbohydrate, protein, and lipid metabolism
Synthesis of fibrinolytics like plasminogen and thrombopoietin, which stimulate platelet production
Regulator of serum glucose. It also clears insulin from the circulation.
Which clotting factors the liver produces?
The liver produces all the clotting factors except for factor 3, factor 4, and von Willebrand.
Vitamin K-dependent clotting factors include
factors 2, 7, 9, 10, as well as proteins C, S, and Z (anticoagulants)
Factor 8 is produced by
Factor 8 is produced by the liver sinusoidal cells and endothelial cells (not by hepatocytes).
Patients with liver failure are at risk of
Hypoglycemia
Identify the Liver function.
The liver produces all the plasma proteins except for _______________
The liver produces all the plasma proteins except for immunoglobulins
The most abundant plasma protein
Albumin
Which protein serves as a blood reservoir for acidic drugs, but it will also bind with basic drugs?
Albumin
Which protein is a blood reservoir for basic drugs?
Alpha-1 acid glycoprotein
Reduced pseudocholinesterase production _________ the duration of __________ and possibly increases the duration of _________ local anesthetics.
This is only a problem with _____________.
Reduced pseudocholinesterase production increases the duration of succinylcholine and possibly increases the duration of ester-type local anesthetics.
This is only a problem with severe liver disease.
_________ is a byproduct of protein metabolism
Ammonia
Failure to clear ammonia leads to
Failure to clear ammonia (hepatic failure or portosystemic shunting) leads to hepatic encephalopathy.
________ byproduct of hemoglobin metabolism
Bilirubin
Which type of bilirubin is neurotoxic?
Unconjugated bilirubin
Phase 1 and Phase 2 of drug metabolism in the liver
Liver function test: Synthetic function
PT and Albumin
Liver function test: Hepatocellular Injury
ASL and ALT
Liver function test: Hepatic Clearance
Bilirubin
Liver function test: Biliary duct obstruction
Alkaline phosphatase, Yglutamyl transpeptidase, and 5-nucleotidase
___________ is very sensitive for acute hepatic injury because factor 7 has a half-life of only 4 - 6 hours
Prothrombin time is very sensitive for acute hepatic injury because factor 7 has a half-life of only 4 - 6 hours.
__________ is not sensitive to acute hepatic injury because it has a half-life of 21 days.
Albumin is not sensitive to acute hepatic injury because it has a half-life of 21 days.
Liver Function Test Table
What is the most common cause of liver cancer?
Hepatitis
What is the most common indication for liver transplantation?
Hepatitis
Etiologies of hepatitis include
viruses
-herpes simplex
CMV
Epstein Barr
hepatotoxins
autoimmune responses
Which type of hepatitis is uncommon in the US?
Hepatitis E
Hepatitis A virus Route of transmission & Antibody
FECAL-ORAL
Anti-HAV
Hepatitis B virus Route of Transmission & Antibody
Parenteral Sexual
Anti-S
Anti- HBc
Anti-HBe
Hepatitis C virus Route of Transmission & Antibody
Parenteral
Anti-HCV
Hepatitis D (Delta) virus Route of transmission & Antibody
Parenteral Sexual
Anti-HDV
Hepatitis E virus Route of Transmission &
Fecal and Oral
Anti-HEV
What is the most common cause of acute liver failure in the US?
Acetaminophen Overdose
What is the most common cause of Drug-Induced hepatitis?
Alcohol
It impairs fatty acid metabolism, which causes fat accumulation in the liver. This leads to hepatomegaly.
__________ impairs fatty acid metabolism, which causes fat accumulation in the liver. This leads to hepatomegaly.
Alcohol
Acetaminophen Overdose treatment
oral N-acetylcysteine within 8 hours of acetaminophen overdose
Max dose of Acetaminophen
4g/day
Drug-Induced Hepatitis manifestation
Usually associated with a late-onset.
It typically presents 2 - 6 weeks after the insult. However, it can be as long as 6 months.
It’s clinically indistinguishable from viral hepatitis, so laboratory analysis is required
Most common cause of chronic hepatitis
Alcoholism
The second most common cause of chronic hepatitis
Hepatitis C
Diagnosis of Chronic hepatitis include
Increased Liver enzymes and bilirubin + histologic evidence of liver inflammation
S/S of chronic hepatitis
jaundice
fatigur
thrombocytopenia
glomerulonephritis
neuropathy
arthitis
myocarditis
In Chronic hepatitis the
______is prolonged and ________ is decreased
PT prolonged
Albumin Decreased
For ________ hepatitis, non-emergent surgery should be postponed until symptoms have resolved and liver function tests return to normal.
For _______ hepatitis, the patient may undergo surgery if the condition is stable.
For acute hepatitis, non-emergent surgery should be postponed until symptoms have resolved and liver function tests return to normal.*
For chronic hepatitis, the patient may proceed to surgery so long as the condition is stable.
What are carcinoid tumors?
Carcinoid tumors consist of slow-growing malignancies composed of enterochromaffin cells and are most found in the GI tract.
Where do carcinoid tumors occur?
Most common places to find carcinoid tumors (about 70%)
Appendix (45%)
Jejunoileum (28%)
Rectum (16%)
Duodenum (4%)
When does carcinoid syndrome develop?
Carcinoid syndrome develops when carcinoid tumors arise outside the drainage field of the hepatic portal venous system or when metastatic disease has replaced so much of the liver as to compromise hepatic synthetic function and systemic symptoms ofserotonin excess occur.
Diagnosis of carcinoid tumor includes
Elevated levels (> 30 mg/24 hrs) of 5-hydroxy indole acetic acid (5-HIAA) in urine. Normal levels are from 3-15 mg/24hrs
Carcinoid Syndrome is the complex of signs and symptoms caused by the secretion of vasoactive substances such as
Serotonin, kallikrein, and histamine into the systemic circulation from carcinoid tumors.
S/S of carcinoid syndrome
A carcinoid crisis manifests as
A potentially life-threatening complication. Manifests as intense flushing, diarrhea, abdominal pain, and cardiovascular signs, including tachycardia, hypertension, or hypotension.
A Carcinoid crisis may occur.
spontaneously or may be provoked by physical manipulation of the tumor, stress, chemical stimulation or tumor necrosis resulting from chemotherapy hepatic artery ligation or embolization
Clinical manifestation of carcinoid crisis
Severe flushing, dramatic changes in BP,arrhythmias, bronchoconstriction, and mental status changes
Treatment for carcinoid crisis
Octreotide 150- 200 mcg every 6-8 hours for 24- 48 hours prior to surgery and continued through the procedure
Carcinoid syndrome treatment
The most effective treatment for carcinoid tumors is complete surgical excision of the tumor, often with partial bowel resection and mesenteric lymphadenectomy.
Somatostatin analogs (Octreotide and Lanreotide )- Suppress luteinizing hormone (LH)responses to gonadotrophin-releasing hormone (GnRH), decrease splanchnic blood flow, and inhibit the release of serotonin, gastrin, vasoactive intestinal peptide, secretin, motilin, and pancreatic polypeptide.*
Serotonin receptor antagonists: Relieve the diarrhea in most patients.* H1 and H2 receptor blockers: Reduce histamine release and prevent the pruritic flush
Hepatic carcinoid tumors receive their blood supply from
the hepatic artery
