Table 3 Stratified care intervention program for postoperative delirium after type A aortic dissection

1. Nursing assessment

1.1 Delirium judgment

1.1 The presence of delirium was determined by the nurse-in-charge on the day of transfer using Nu-DESC, which assesses five clinical features: disorientation, behavioral abnormality, verbal communication abnormality, illusions/hallucinations, and psychomotor retardation, each of which is scored according to the presence or absence and severity of clinical symptoms: absent = 0, mild = 1, moderately severe = 2, with a maximum score of 10. Delirium is likely to be present when the total score is ≥ 1. Diagnosis of delirium: Consultation with a psychiatrist was requested to confirm the diagnosis of delirium according to the relevant content in the Diagnostic and Statistical Manual of Mental Disorders, 5th edition. Frequency of assessment: 1 assessment per shift for high-risk group and delirium, 1 assessment per day for low-risk group

Nurse doctor

1.2 Delirium risk stratification

1.2.1 A risk prediction scoring model was used to differentiate non-delirium patients into high- and low-risk groups. The model scoring criteria were: age > 55.5 years (1 point), male (1 point), preoperative lactate value > 1.85 mmol/L (1 point), duration of deep hypothermic circulatory arrest > 36.5 min (1 point), length of stay in the CCU > 8.5 days (2 points), and postoperative comorbidity with other complications (1 point). When the score was ≤ 4, the person was at low-risk of delirium; when the score was ≥ 5, the person was at high-risk of delirium

Nurse

1.3 Delirium risk-related assessment

1.3.1 Risk factors are assessed using the Delirium Risk Factor Assessment Form and the Delirium High Risk Medication Assessment Form. The low-risk group was once assessed on admission and at the change in condition; the high-risk group and those with delirium were assessed once daily

Nurse doctor

Nursing care measures

2.1 Stratified care management

2.1.1 Those in the high-risk group and those with delirium implemented the early activity, pain, sleep, cognitive function, physiological needs, and complication management developed in this protocol in addition to routine care, and timely correction of risk factors for delirium based on daily assessments

Nurse

① Early activity management. Patients were helped to move passively in bed on the day of transfer. On the 2nd day, those who could move actively were helped to sit at the bedside and assisted to move their lower limbs. For those who can stand for ≥ 5 min, they can try to assist the bedside walking and gradually move to the ward corridor, 2 times/day, 10–20 min/time

Nurse rehabilitation therapist

② Pain management. Assessed by numerical rating scale (NRS) with expected target NRS ≦ 3 points. Non-pharmacological interventions include massage for pain other than wounds, cold therapy for procedural pain management, relaxation, and breathing exercises. Pharmacologic interventions: intravenous pumping of remifentanil injection for severe pain and irritability

Nurse

③ Sleep management. Turn cell phones to vibrate mode; check and lower monitor volume to reduce false alarms; change medications at night before micropump alarms. Ask patients if they need to provide eye masks and earplugs

Nurse

④ Cognitive function exercise. Assess patients’ cognitive function using the MMSE scale. Place a clock and calendar in the room; avoid unnecessary environmental changes and ensure 1 familiar family member is with the patient during hospitalization. Remind the patient of today’s date and time each morning. Tell the patient what stage of recovery he/she is at and what cooperation he/she needs to do today

Nurse

⑤ Physiologic needs management. After transferring to the ward, the indications for removal of the indwelling urinary catheter were assessed daily, and the indwelling urinary catheter was removed as early as possible. Patients were asked about urination and defecation, and those who had not relieved their bowels for ≥ 3 days were given 40 ml of Keserol in the anus according to the doctor’s instructions

Nurse

⑥Complication management. Good respiratory management, every 2 h turn over and pat the back, do deep breathing training, follow the doctor’s prescription of nebulized inhalation 3 times/day, guide effective sputum coughing, sputum coughing is not good to use stimulating sputum removal method. Maintain oxygen saturation > 90%. If it is below 90%, give oxygen according to medical advice. Early detection and active cooperation with doctors to treat infections; avoid unnecessary intubation

Nurse

2.1.2 The low-risk group was given routine care, and the targeted interventions in the above program were implemented if risk factors existed, such as cold therapy, relaxation, and respiratory training before chest tube removal for those with significant pain, and pain medication for those with severe pain that could not be relieved, as prescribed by the doctor

Nurse

2.2 Management of patients with delirium

2.2.1 Those with non-severe delirium are managed as above

Nurse

2.2.2 In addition to the routine care of severe delirium patients, the following management was implemented: ① sedation management, dexmedetomidine night sedation (21:00 to 06:00 the next day) as prescribed by the doctor, with the goal of mild sedation, and vigilance for bradycardia and hypotension; ② constraint management, the use of psychiatric protective constraints implementation assessment form and lifting the assessment form to assess the patient’s constraint needs scientifically, and the implementation of the principle of individualized reduction of constraints, least constraints; ③ Nursing safety management, the implementation of access control management at the entrance and exit of the ward, to avoid patient loss and escape; confiscation of scissors, fruit knives, sharps, etc. at the patient, to avoid injuries

Nurse

2.3 Family support

2.3.1 Health education. In addition to routine education, on the 1st, 3rd, and 5th days after the patient’s transfer, the team members explained delirium-related knowledge to the family members by means of videos, leaflets, classroom lectures, etc. The education focused on what delirium is, prevention techniques, indicators of onset, and how to manage with it

Nurse

2.3.2 Family participation. ①Instruct family members to monitor the patient’s symptoms and signs daily and report any delirium to healthcare personnel promptly. ② Encourage family members to engage in early postoperative rehabilitation and interact regularly during hospitalization. ③ Provide delirium care by being patient and tolerant of the patient’s odd behavior. Use positive motivational language to encourage the patient and help them return to normal mental state as soon as feasible

Patient’s family