my $sth_udt = $dbh->prepare(qq{UPDATE items set price = ? WHERE oid = ?});

while (my $val = $sth->fetchrow) {
    my $price = param("item_${val}_price");
    $sth_udt->execute($price, $val);
    # You could probably just do:
    # $sth_udt->execute(param("item_${val}_price"), $val);
}