pass PatID field when add new records

Thanks in advanced if anyone can help me out ASAP.

I have two forms, frm_searchPatient and frm_Labs. My intend is to click
AddLab button on the 1st form, then open the 2nd form to add additional
information to current PatID. The problem is that the datafield, PatID,
doesn't get passed to the frm_Labs.

Access VBA code of frm_searchpatient is the following:


Option Compare Database
Option Explicit

Private Sub PatID_Combo_AfterUpdate()
' Find the record that matches the control.
Dim rs As Object

Set rs = Me.Recordset.Clone
rs.FindFirst "[PatID] = '" & Me![PatID_Combo] & "'"
If Not rs.EOF Then Me.Bookmark = rs.Bookmark
End Sub

Private Sub addLabs_Click()

On Error GoTo Err_AddLabs_Click
Dim stDocName As String
Dim stLinkCriteria As String

stDocName = "frm_Labs"
' Open Labs form in data entry mode and store PatientID in
' the form's OpenArgs property.
stLinkCriteria = "[PatID]=" & "'" & Me![PatID] & "'"
DoCmd.OpenForm stDocName, , , stLinkCriteria

' Close Labs form.
'DoCmd.Close acForm, "frm_Labs"

' Give data entry control focus.
Forms![frm_Labs]!SpecNum.SetFocus

Exit_AddLabs_Click:
Exit Sub

Err_AddLabs_Click:
MsgBox Err.Description
Resume Exit_AddLabs_Click

End Sub

Private Sub Form_Current()
On Error GoTo Err_Form_Current
' If the Labs form is open, show current PatID.

Dim strDocName As String
Dim strLinkCriteria As String

strDocName = "frm_labs"
strLinkCriteria = "[PatID] = Forms![Labs]![PatID]"


Exit_Form_Current:
Exit Sub

Err_Form_Current:
MsgBox Err.Description
Resume Exit_Form_Current

End Sub

VB code for frm_Labs:

Private Sub PatID_AfterUpdate()
' If OpenArgs property isn't null, set PatID to value of form's OpenArgs
' property. OpenArgs will have a value if Labs form is opened by clicking
' AddLabs command button on Labs form.
If IsNull(Forms!Labs.OpenArgs) Then
Exit Sub
Else
Me!PatID = Forms!Labs.OpenArgs
End If

End Sub
Private Sub Form_Current()
On Error GoTo Err_Form_Current

' If the Labs form is open, show current PatID.

Dim strDocName As String
Dim strLinkCriteria As String

strDocName = "frm_labs"
strLinkCriteria = "[PatID] = Forms![Labs]![PatID]"


Exit_Form_Current:
Exit Sub

Err_Form_Current:
MsgBox Err.Description
Resume Exit_Form_Current

End Sub

.