diff --git a/lib/istoredp.js b/lib/istoredp.js
index 4f610c7c..d002f8ed 100644
--- a/lib/istoredp.js
+++ b/lib/istoredp.js
@@ -60,33 +60,50 @@ const db2Call = (callback,xlib,xdatabase,xuser,xpassword,xipc,xctl,xml_input_scr
         [xml_input_script, db.SQL_PARAM_INPUT, 0],
         [xmlOut, db.SQL_PARAM_OUTPUT, 0],
       ];
-        
+
+    const cleanup = () => {
+      stmt.close();
+      conn.disconn();
+      conn.close();
+    };
+
     if(sync == true) {  // Sync Mode
-      stmt.prepareSync(sql);
-      stmt.bindParamSync(bindParams);
-      stmt.executeSync((outArray) => {  //out is an array of the output parameters.
-        if(outArray.length == 1)
-          callback(outArray[0]);  // For XML service, there is always only one return XML output. So handle it directly.
-        else
-          callback(outArray);  // For multiple return result, caller should handle it as an array.
-        delete stmt;
-        conn.disconn();
-        delete conn;
-      });
+      try {
+        stmt.prepareSync(sql);
+        stmt.bindParamSync(bindParams);
+        stmt.executeSync((outArray) => {  //out is an array of the output parameters.
+
+          if(outArray.length == 1)
+            callback(outArray[0]);  // For XML service, there is always only one return XML output. So handle it directly.
+          else
+            callback(outArray);  // For multiple return result, caller should handle it as an array.
+        });
+      }
+      finally {
+        // Ensure we clean up
+        cleanup();
+      }
     } else {  // Async Mode
       stmt.prepare(sql, (err) => {
-        if(err) throw err;
+        if(err) {
+          cleanup();
+          throw err;
+        }
+
         stmt.bindParam(bindParams, (err) => {
-          if(err) throw err;
+          if(err) {
+            cleanup();
+            throw err;
+          }
+
           stmt.execute((outArray, err) => {  //out is an array of the output parameters.
+            cleanup();
             if(err) throw err;
+
             if(outArray.length == 1)
               callback(outArray[0]);  // For XML service, there is always only one return XML output. So handle it directly.
             else
               callback(outArray);  // For multiple return result, caller should handle it as an array.
-            delete stmt;
-            conn.disconn();
-            delete conn;
           });
         });
       });
@@ -96,4 +113,4 @@ const db2Call = (callback,xlib,xdatabase,xuser,xpassword,xipc,xctl,xml_input_scr
   }
 }
 
-exports.db2Call = db2Call;
\ No newline at end of file
+exports.db2Call = db2Call;