Calling stored procedures in Laravel 5.5 using SQL Server with output

I have the following stored procedure:

declare @CodigoRet int

exec Generator 'LancaContaContabil', @Codigo = @CodigoRet output

Select @CodigoRet

• OBS: the LancaContaContabil is my table and the Codigo is the PK for that table

And I'm trying to call this procedure in Laravel 5.5 but it gives me the error: "The active result for the query contains no fields":

$results = DB::select(DB::raw('DECLARE @CodigoRet INT; execute Generator 
\'LancaContaContabil\', @Codigo = @CodigoRet OUTPUT;'));
echo $results;
die;

Same error using the variant without dbraw:

$results = DB::select('DECLARE @CodigoRet INT; EXEC Generator         
\'LancaContaContabil\', @Codigo = @CodigoRet OUTPUT;');
echo $results;
die;

Also tried with statement, but the return is always 1:

$results = DB::statement('DECLARE @CodigoRet INT; EXEC Generator 
\'LancaContaContabil\', @Codigo = @CodigoRet OUTPUT;');
echo $results;
die;

EDIT: I created the procedure under the name 'testeproc' and now i've tried this, with the same error as above:

$results = DB::select('EXECUTE testeproc');
echo $results;
die;

What am I doing wrong?

via Chebli Mohamed