Does Cardiopulmonary Bypass Change Olfaction?

Objectives: To investigate the incidence of anosmia arising in patients after undergoing cardiopulmonary bypass, and compare it to a control group.

Hypothesis: Patients undergoing cardiopulmonary bypass may suffer from anosmia.

Methodology: Potential participants will be identified via scheduled operating lists at Manchester Royal Infirmary. Suitable patients will be informed, including informational leaflets about the study, and permissions sought with an informed consent form. Once recruited, when the patients come for their pre-operative assessment, olfactory assessment will be carried out using the Sniffing Sticks smell kit and a validated questionnaire (Dresden Questionnaire of Olfactory Disorders). The Sniffing Sticks smell kit composes of 12 different pen-like odour dispensers. Each stick is presented to the patient who then chooses from four different answers, the one that best represents the odour. The patient then receives a score of 0 to 12. A reassessment via the same questionnaire and smell kit is repeated after 1 week or just before discharge (whichever is earlier) after the patient's surgery.

Data Management and Statistical Analyses: All participant information will be stored electronically in a password protected trust computer. Participant identifiers will also be kept in a separate password protected folder from the main database of individual participant information. We will use MS Excel for compiling the data.

Study Type: Prospective, single-centre, observational study