使用PDO和PHP从MSSQL表获取最后插入记录的id

I am trying to get the id of the last record inserted in an mssql database using pdo via php. I HAVE read many posts, but still can't get this simple example to work, so I am turning to you. Many of the previous answers only give the SQL code, but don't explain how to incorporate that into the PHP. I honestly don't think this is a duplicate. The basic insert code is:

$CustID = "a123";
$Name="James"
$stmt = "
        INSERT INTO OrderHeader (
            CustID, 
            Name 
        ) VALUES (
            :CustID, 
            :Name
        )";
        $stmt = $db->prepare( stmt  );
        $stmt->bindParam(':CustID', $CustID);       
        $stmt->bindParam(':Name', $Name);
        $stmt->execute();

I have to use PDO querying an MSSQL database. Unfortunately, the driver does not support the lastinsertid() function with this database. I've read some solutions, but need more help in getting them to work.

One post here suggests using SELECT SCOPE_IDENTITY(), but does not give an example of how incorporate this into the basic insert code above. Another user suggested:

    $temp = $stmt->fetch(PDO::FETCH_ASSOC);

But, that didn't yield any result.