Bam Margera's mother April says her son was "severely dehydrated" and that's why the West Chester area "Jackass," was rushed to a local hospital yesterday. TMZ reported that a 911 call mentioned a "possible overdose." April was interviewed this morning on 93.3 WMMR's Preston & Steve show on which the Margera family have been regular guests for years. April told P&S that Bam, who was shooting scenes for MTV's "Nitro Circus," doesn't take care of himself while working. Bam's publicist has not returned our request for comment, but a friend says he's doing better.