In England, hip and knee replacement are the second and third most common surgeries, with 115,758 and 81,590, respectively, performed in 2014. Abdominal surgical procedures such as cholecystectomy are the following most common procedures. While short-term opioid use has an established role in managing acute pain following these surgeries, prolonged use is linked with opioid-related harms and opioid diversion.[3, 4] In the UK, the type, amount, and formulation of opioids commonly prescribed by general practitioners following discharge after surgery, the timing of opioid cessation following surgery and the risk factors associated remain unexplored. Therefore, the findings from this research will inform clinical practice guidelines to tailor postoperative pain management plans to avoid unnecessarily prolonged opioid use.
The repeated cross-sectional analysis aims to describe the characteristics of the first opioid prescription received following surgery discharge date. Patients with codes for one of four selected surgical procedures; (colectomy, cholecystectomy, total hip arthroplasty or total knee arthroplasty) and available for linkage to HES and have an opioid prescription from their General Practitioner within 30 days from discharge will be included. Descriptive statistics will be used to report opioid utilisation measures each year and stratify patients into opioid naïve and prior opioid exposed groups. Linear trend analysis will be conducted on annual opioid utilisation measures, and the percentage change between 2011 and 2020 data for variables will be reported.
A cohort design will be used to identify time-to-discontinuation of opioids in days with follow up occurring over 12 months from the discharge date. Time to opioid discontinuation will be defined as 90 days opioid-free—no current or prior opioid prescription covered those 90 days. Kaplan-Meier survival curves will be used to graph time to discontinuation. Then patient factors affecting time to opioid discontinuation will be identified using cox proportional hazard models to estimate hazard ratios.
C. Outcomes to be Measured
1. The characteristics of the first opioid prescription received from primary care in the first 30 days following selected orthopaedic and abdominal surgical procedures. Including the type, formulation, and amount of the opioid;
2. Time to opioid discontinuation in days following selected orthopaedic and major abdominal surgical procedures;
3. Predictors affecting time to opioid discontinuation following selected orthopaedic and major abdominal surgical procedures.
Roger Knaggs - Chief Investigator - University of Nottingham
Reham Baamer - Corresponding Applicant - University of Nottingham
David Humes - Collaborator - University of Nottingham
Dileep Lobo - Collaborator - University of Nottingham
Li Shean Toh - Collaborator - University of Nottingham
HES Admitted Patient Care;ONS Death Registration Data;Patient Level Index of Multiple Deprivation