Cardiac Surgery as an Acute Kidney Injury Risk Factor

This example shows data collected in a study focused on the prevention of AKI after cardiac surgery. Information collected included the type of cardiac surgery performed and details about the actual surgical procedures, because these are known risk factors for AKI. When subjects were scheduled for a valve replacement and a coronary artery bypass graft (CABG) at the same time, these procedures were listed separately.

PRLNKGRP was given a value of "STYSUR" for all components of the study surgery and PRLNKID was populated for CABG surgeries. These variables were used to enable linking to additional information relevant to study surgeries and CABG procedures. PRDECOD was assigned using MedDRA. Note: The PRMODIFY term would be used if the PRTRT term was modified for coding.

Information collected on the number of grafts that were performed was represented in the FA domain. FALNKID was assigned by the sponsor using a sequential number for each CABG surgery (e.g., CABG1, CABG2) and serves as a linking variable to the parent PR domain. Although VISITNUM is an expected variable, the sponsor did not assign visit numbers.

The sponsor collected information on whether the subject experienced cardiac arrest during the study surgery. In this study, cardiac arrest was considered a clinical event, rather than an adverse event, because the surgery was performed prior to the start of study treatment. The cardiac arrest was considered to be related to the study surgery session, so the sponsor decided to relate the CE record to the components of the study surgery in the PR domain (CELNKGRP = "STYSUR").

RELREC is used to link data from the CE, PR, and FA domains.