Gastrointestinal Disorders Flashcards
what diagnostic test can be done to check if a patient is on apixaban/edoxaban/rivaroxaban, if the AC is therapeutic or supratherapeutic?
direct measurement of factor Xa levels
since factor Xa level measurement is not readily available what other lab test might be helpful?
PT and INR might be elevated; but they might still be normal in a therapeutic or supratherapeutic patient
what diagnostic test can be done to check if a patient is anticoagulated w/ dabigatran?
thrombin time
what test is highly sensitive in excluding clinically therapeutic dabigatran therapy and eliminates it as a contributor to clinically relevant bleeding?
a normal thrombin time
if a thrombin time is elevated does that point to one specific DOAC as the culprit?
no, it can be any of the DOACs; a normal thrombin time only eliminates dabigatran as the culprit
in a patient who p/w bleeding while taking a DOAC, evaluation should be made as to whether or not it is a major bleed; what are the 2 main determining factors?
- site of bleed
- volume of bleed
what site of bleeding are considered critical?
- intracranial
- intraocular
- intra or extra-axial spinal hemorrhage
- pericardial tamponade
- posterior epistaxis
- intrathoracic
- intraabdominal
- retroperitoneal
- intramuscular
- intraarticular
intraluminal GI bleeding is not considered a critical bleeding site; what might make a GIB considered to be major?
the volume of bleed leading to hemodynamic instability
what is the reversal antidote for factor X (abiXABAN, edoXABAN, rivoroXABAN) agents?
andeXanet alpha
what are the 2 major concerns regarding administration of andexanet alpha?
- cost of medication (stupid expensive)
- rebound thrombophilia w/ subsequent high rates of thrombotic events
what can be used to reverse anti-Xa DOACs if andexanet alpha is not available?
4-factor prothrombin complex concentrate (4F-PCC)
4-factor prothrombin complex concentrate (4F-PCC) contains what?
factors II, IX, X, and VII
what must be given in conjunction w/ 4F-PCC and why?
- vitamin K 10 mg ivp
- factors II, IX, X, and VII are vitamin K-dependent coagulation factors
what is the reversal antidote for dabigatran?
idarucizumab
what treatment measures are NOT helpful in reversing factor-Xa DOACs?
- FFP; contains very little factor X
- cryoprecipitate; does contain any factor X
what is the mechanism of hepatotoxicity from acetaminophen overdose?
depletion of glutathione which overwhelms glucuronidation pathway, leading to a shift in metabolism toward NAPQI production which is a hepatotoxic metabolite
how does N-acetylcysteine (NAC) help in acetaminophen overdose?
replenishes glutathione activity and restores glucuronidation pathway
treatment decisions for acetaminophen overdose are based on what?
serum acetaminophen concentration measured at least 4 hours after a single overdose when absorption is complete
the Rumack-Matthew nomogram for acetaminophen toxicity should NOT be used under what scenario?
- if the h/o overdose time is NOT reliable
- patient has been taking acetaminophen chronically
- chronic alcohol use
- preexisting liver disease
what are a couple of reasons why the Rumack-Matthew nomogram cannot be used for acetaminophen toxicity in a patient w/ chronic alcohol use?
- chronic alcohol ingestion also depletes glutathione and upregulates CYP2E1, leading to decreased glucuronidation and increased NAPQI production
- alcoholism may lead to inordinate delays in seeking medical attention
in patients whom the Rumack-Matthew nomogram cannot be used to assess hepatotoxicity risk, what is the best next step?
treat w/ NAC
treatment for presumed esophageal variceal bleed
octreotide
treatment for variceal bleed
EGD w/ banding followed by emergent transjugular intrahepatic portosystemic shunting (TIPS)
EGD w/ banding followed by TIPS has what benefits?
- reduces recurrent esophageal bleeding
- reduces 3-month mortality