It's one of the risks of that surgery; Murtha was no doubt told of possible complications and signed his consent for surgery.
Peritonitis, a painful way to go. Lots of American troops were gut-shot by Murtha and Code Pink's "insurgent" pals in Irag; some dying from peritonitis as well. Almost poetic.
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You know, he was probably on an aspirin regimen for BP too. Are those the insurgents from Iran?????