A filibuster of a package of spending extensions could cause physicians to see a 21% drop in Medicare reimbursement rates.

The blocking action by Sen. Jim Bunning (R-KY) triggers a decade-old provision that automatically reduces Medicare payments to physicians whenever federal spending outpaces the gross domestic product (GDP.)

"It is shocking that the Senate would abandon our most vulnerable patients, making them the collateral damage of their procedural games," American Medical Association President J. James Rohak said in a statement.

Since 2003 Congress has routinely intervened to prevent the cuts from occurring.  A similar reduction occurred in 2008, but Congress acted quickly to restore the payments.

This latest reduction was slated to occur January 1, but a two-month delay was engineered in October by House Speaker Nancy Pelosi, with the House passing another temporary fix on February 25.

Senate Majority Leader Harry Reid had attempted to finally resolve the payment issue permanently last fall, but was blocked by Republicans and some Democrats that balked at the cost of the legislation.  The failure was something of an embarrassment for the AMA, who thought they had sufficient support to pass it.

Because stopping the filibuster and reviving the original measure could be a lengthy process, Reid announced that he will bring up a new bill this week to provide a longer extension on the Medicare payments, as well as some Medicaid relief for states.

In the short term, however, physicians may not feel the cuts.  On February 26 CMS sent out word that, beginning March 1, contractors would hold physicians’ claims for 10 business days to give Congress time to resolve the payment issue.