Under what circumstances would you consider transitioning back to a ventricular peritoneal shunt from a ventricular-pleural shunt?  

If a VPleural shunt is working and well tolerated, there is generally no reason to move it, as for many older patients (usually beyond early childhood) these shunt are well tolerated with no long term complications. If there are recurrent issues, such as pleural effusions or a patient with poor resp...