Post-operative delirium (POD) is a common complication of elderly patients with reported incidence ranging from 15% to 50%. It is associated with adverse outcomes, including longer length of hospital stay, decline in function and cognition, increased risk of nursing home placement, and death.
Patients older than 70 years of age with hip fractures have more than threefold increased risk of developing POD and the hypoactive subtype is more likely to develop in people over the age of 80 .
Screening tools for predicting risk of POD should consider ease of implementation in a busy preoperative setting. 
The MoCA(Montreal Cognitive Assessment), the MMSE(Mini Mental State Examination) and mini-Cog tests have been studied in the peri-operative setting  for assessment of cognition. However, the latter two are more time consuming and not freely available for use. 
Most commonly reported tools for the diagnosis of POD include CAM score, 4AT, besides other tools like Delirium detection scale(DDS).
Limited Indian data exist on the incidence of POD.

The aim of this study is to find the proportion of patients developing post-operative delirium among those undergoing elective orthopaedic lower limb surgeries and the effectiveness of a risk assessment tool PROPDESC to predict development of post- operative delirium in such patients.
This will help identify at risk patients and therefore modify peri-operative management.
Study tools used- PRe-Operative Prediction of post-operative DElirium by appropriate SCreening( PROPDESC), Montreal Cognitive Assessment (MoCA), Confusion Assessment Method(CAM). 
All the patients meeting the inclusion and exclusion criteria will be enrolled.
On the day before surgery, Informed consent for delirium assessment will be obtained.
In addition to the routine Pre-Anaesthetic evaluation, the PROPDESC score will be calculated using Age, ASA Classification, NYHA Classification, Surgical risk and Montreal Cognitive Assessment (MoCA)
Intraoperatively, the type and duration of surgery and of anaesthesia, as well as intra-operative complications, if any, will be noted.
Postoperatively, patients will be interviewed with CAM-Sand 4AT on postoperative days 1, 3 and 5. Patients with at least one postoperative interview will be included in the analysis.
Outcome parameters noted will include, occurrence of any post-operative complications, length of hospital stay and death/ discharge. Total costs of hospitalisation will also be