Automated Pupillometry in Patients Underwent Cardiac Surgery to Predict Postoperative Delirium

Exploratory Study on the Role of Automated Pupillometry in Patients Underwent Cardiac Surgery to Predict Postoperative Delirium

The rate of postoperative delirium in patients who underwent cardiac surgery is very high. Different predictors and/or scores were studied for the prediction of Post Operative Delirium (POD)after heart surgery, but none of them was validated. The investigators aim to explore the role of pupillary alterations during anesthesia in open-heart surgery.

The goal of this prospective study is to evaluate if pupil alterations during cardiac surgery, evaluated by an automated pupillometer (NPi-200) ( AP), could predict postoperative delirium.

Consent was obtained during the hospitalization before the planned surgery.

On the day of surgery, before general anesthesia is started, Near-infrared spectroscopy (NIRS) sensors are applied to the patient's forehead bilaterally and the baseline value is recorded. Pupils' variables (i.e., diameter, % constriction, constriction velocity, dilation velocity, latency, NPi) are also recorded from both the right and left eye with AP (NPi-200).

From the induction of anesthesia, pupillary variables in both eyes are recorded and measured every 30' such as the concomitant NIRS values (at least one measurement per eye per operative phase). Moreover, hemodynamic and respiratory parameters concomitant with the pupillary measurements are measured.

Following surgery, the patient is transferred to the Cardiac Intensive Care Unit. There, NIRS monitoring as as well as automated pupillometry measurements will be maintained until the patient regains consciousness (defined as RASS sedation scale >-3).

Once the patient has regained consciousness (RASS>-3), is assessed twice a day (morning and afternoon) with the Confusion assessment method-intensive care unit (CAM-ICU) score by the nursing staff and/or medical staff. The presence or absence of POD will then be reported as well as any pharmacological and non-pharmacological treatments.

Any neurological complications and diagnostic investigations arising in the post-operative period will also be noted.

Inclusion Criteria:

• Adult patients undergoing elective open cardiac surgery (>18 yr)
• Elective open cardiac surgery and cardiopulmonary bypass

Exclusion Criteria:

• Patients <18 years of age
• Emergency surgeries
• Heart operations, not including extracorporeal circulation
• Surgery for aortic arch dissection with hypothermia and/or circulatory arrest
• Patients affected by psychiatric disorders undergoing with or without neuroleptic therapy
• Patients who have the refused consent
• Patients with ocular problems (acute or previous trauma to one or both eyes, blindness, ocular prosthesis)