Stupid question

I have the following: $dsn = "mysqli://$username:$password@$hostname2/$database"; $options = array(

    'debug' => 3,
    'result_buffering' => false,

); $dbh =& MDB2::factory($dsn, $options);

        if (PEAR::isError($mdb2))
        {
                die($mdb2->getMessage());
        }

function tallyCart($_u_id,$dbh){

       while($row = $result->fetchrow(MDB2_FETCHMODE_ASSOC)) {
                $_showCheckOut=1;
                $_pdetail=new ProductDetail($row{'product_ID'}, $row{'product_Quantity'}, $_u_id);
                 $_getSubTotal += $_pdetail->_subTotal;
                 $_counter++;
        }

} I'm getting: Call to undefined method MDB2_Error::fetchrow() anyone have any ideas? Can I not pass a database handle to a function? Thanks, Curtis