CREATE TABLE  "TDBParams"  (
F_PARAMID number NULL,
F_NAME varchar ( 256 ) NULL
)
CREATE OR REPLACE PROCEDURE UpdDBParams (Name IN varchar,ParamId IN number)
IS BEGIN  -- Кстати, не заметил разницы "AS"/"IS"
 
    INSERT INTO  "TDBParams"  (F_PARAMID,F_NAME)
    VALUES (ParamId,Name);
END;

// дополнительно при задании параметров вызываем:
pCommand->CreateParameter(_bstr_t( "RetVal" ),adInteger,adParamReturnValue,- 1 ,COleVariant((long)  0 ));
pCommand->Parameters->Append(pParameter);

pCommand->CreateParameter(_bstr_t( "result" ),adVarNumeric,adParamReturnValue,- 1 ,COleVariant((long)  0 ));
pCommand->Parameters->Append(pParameter);

CREATE OR REPLACE PROCEDURE UpdDBParams (p_errorcode OUT number,Name IN varchar,ParamId IN number)
AS BEGIN
    INSERT INTO  "TDBParams"  (F_PARAMID,F_NAME)
    VALUES (ParamId,Name);
  EXCEPTION      
    WHEN OTHERS THEN  
      p_errorcode:= SQLCODE;    
END;
...
В Command самым первым параметром добавляем возвращаемое значение:
_ParameterPtr pParameter;
pParameter = pCommand->m_pCommand->CreateParameter(_bstr_t( "P_ERRORCODE" ),adSmallInt,\
             adParamOutput,- 1 ,COleVariant((long)  0 ));
pCommand->m_pCommand->Parameters->Append(pParameter);