What is the recommendation for the maximum PT/INR for an intracranial procedure?

Sixth Edition Greenburg recs an INR of 1.4 but does not provide a reference.  Most of my attendings want 1.3 before we stick in an EVD.  I’ve searched the literature but cannot find a specific paper.

Anybody got a reference?

This INR is based on that considered safe for performing TIPS (transjugular intrahepatic portosystemic shunts)...the theory being that if invasive procedures can be performed safely on the hypervascular liver, so too can they be done on the brain.

Do you have a a reference for this?

Besides, the International Normalized Ratio is really only accurate with warfarin anticoagulation and is not recommended for hepatic pathologies.

What in the hell are you talking about?!  The INR (or as you so eloquently state the “international normalized ratio") is a part of calculating not only CHILD class which predicts survival in LIVER failure patients...but the MELD score wich is used to determine who gets a LIVER transplant. So it is actually IDEAL for hepatic pathologies.

The only thing worse than no information is mis-information.  remember that NRA4LIFE...a neurosurgeon should know better than to throw around this garbage

-LS

ps. pwned

lazarussign - 31 May 2010 02:36 PM

What in the hell are you talking about?!  The INR (or as you so eloquently state the “international normalized ratio") is a part of calculating not only CHILD class which predicts survival in LIVER failure patients...but the MELD score wich is used to determine who gets a LIVER transplant. So it is actually IDEAL for hepatic pathologies.

The only thing worse than no information is mis-information.  remember that NRA4LIFE...a neurosurgeon should know better than to throw around this garbage

-LS

Ithink the OP was asking the rationale behind the current set-point of maximum INR for the safety of performing intracranial procedures.

(Really?) brought up the point that if an anastomosis can be performed around a hypervasculare liver, i.e. the TIPS procedure in cirrhosis with an INR of 1.3-1.4, then similar procedures could also be done on the brain.

The CHILD / MELD score is irrelevant in this discussion because the parameter, i.e. INR / PT, reflects the functional capacity of the liver. INR / PT is the first parameter to rise in liver failure mainly because the half-life of factor VII is the shortest in the coagulation pathway. It is an indicator of the degree of liver failure and thus prognosis and is not meant to pose a surgical challenge has to whether a liver transplant was feasible or not, as FFP can easily correct this abnormal lab finding.

By the way, you should really watch your tone on how you talk to your fellow colleagues and to people in general, because people like you can really mess up a good teaching atmosphere.

"It is an indicator of the degree of liver failure and thus prognosis and is not meant to pose a surgical challenge has to whether a liver transplant was feasible or not, as FFP can easily correct this abnormal lab finding”

Incorrect. Childs Class predicts mortality of pts with cirrhosis undergoing surgery..... and thus is a direct indicator of the feasibility. You can correct the INR with FFP, PCC, Factor VIIa, etc......but the uncorrected number is part of a set of objective markers that predict mortality and thus feasibility.

Sorry my tone is offending, but I am more offended when people pass out mis-information as fact. People get hurt that way....physically hurt that is...not emotionally

We, too, use 1.3 as a cutoff for cranial procedures, but the basis behind that cutoff is more likely tradition than evidence.  How about we write a review paper on the significance of the INR for intracranial procedures?

J Neurosurg 112:307–318, 2010

“Emergency reversal of anticoagulation and antiplatelet therapies in neurosurgical patients”

A very good paper but it still does not directly address what INR is ‘safe’ or ‘unsafe.’ Maybe I’ll just give coumadin to dogs and stab ‘em with an EVD.