Postoperative cognitive decline in patients undergoing elective laparotomy for cancer surgeries in a tertiary care centre: A prospective cohort study

Aim: To study postoperative cognitive decline among cancer patients undergoing elective laparotomy surgeries under general anaesthesia in a tertiary care centre

Study Design**:** A single-centred, prospective cohort study.

Study Site**:** Department of Onco-Anaesthesia and Palliative Medicine, BRAIRCH, AIIMS, New Delhi and NCI AIIMS Jhajjar.

Study Duration**:** Prospective analysis of case-specific data on patients undergoing elective laparotomy for cancer from 1st July 2024 to 31st December 2025.

Inclusion criteria**:**

Adult patients (≥18 years of age).

Undergoing elective laparotomy for cancer under general anaesthesia.

Exclusion criteria**:**

Patients who cannot read or write.

Patients who cannot understand either English or Hindi.

Patients with known neuropsychiatric disorders.

Patients with a history of central nervous system disease or cerebrovascular disease with sequelae.

Patients with a history of developmental or mental intellectual disability and cognitive impairment.

Patients with CNS metastasis.

Preoperative Visit

Patients matching the inclusion criteria will be recruited.

Written and informed consent will be obtained from the patients after explaining the study protocol and answering any queries.

Baseline assessment of neurocognitive status will be done by a battery of tests, including Hindi Mental State Examination (HMSE), Addenbrooke’s Cognitive Examination–III (ACE–III), Trail Making Test–A (TMT–A), Trail Making Test–B (TMT–B), one day before surgery.

The demographic profile, comorbidities, medication history, administration of neoadjuvant chemotherapy (NACT), neoadjuvant radiotherapy (NART).

Patient’s comorbidity status will be evaluated by Charlson Comorbidity Index (CCI).

Clinical Frailty Scale (CFS) will be used to assess frailty of the patient.

Anaesthesia Technique

All laparotomy cases are usually done under general anaesthesia with or without regional anaesthesia.

ASA Standard-II monitoring is done for all patients with advanced cardiac output monitoring done for high-risk surgeries.

Postoperative analgesia is usually based on anaesthesiologists’ discretion, and various options include local anaesthetic infusions in epidural, Epidural morphine or interfacial truncal plane blocks or intravenous morphine/fentanyl by patient-controlled analgesia pumps when regional anaesthesia cannot be administered.

Standard hospital procedures and protocols for anaesthesia, surgery and perioperative care will be followed.

Decisions about the exact anaesthetic techniques will be at the discretion of the concerned anaesthesia team independent of the investigator and will be recorded. The type of surgery, surgical duration, and blood loss shall be recorded.

Observation (1 week)

Patients will be followed one week after the surgery, and details related to postoperative analgesia and any complications, including blood transfusion, shall be recorded.

Assessment of neurocognitive status will be repeated using a battery of tests, including HMSE, ACE–III, TMT–A, and TMT–B.

Postoperative complications will be evaluated by Clavien Dindo Complication Classification (CDCC) at 1 week.

Observation (3 months)

Patients will be followed three months after the surgery.

Assessment of neurocognitive status will be done using a battery of tests, including HMSE, ACE–III, TMT–A, and TMT–B.

The treatment administered to the patient during this period will be noted, including chemotherapy, radiotherapy, and combination therapy.

Primary Outcome:

Incidence of postoperative cognitive decline in patients undergoing elective laparotomy for cancer surgeries under general anaesthesia at one week post-surgery.

Secondary Outcomes:

Incidence of postoperative cognitive decline in patients undergoing elective laparotomy for cancer surgeries under general anaesthesia at three months post-surgery.

Predictors of postoperative cognitive decline in patients undergoing elective laparotomy for cancer surgeries under general anaesthesia.

Tools

The following tools will be used to assess the study parameter of postoperative cognitive decline:

***1.***Hindi Mental State Examination (HMSE)

2. Addenbrooke’s Cognitive Examination–III (ACE–III)

**3.**Trail Making Test–A (TMT–A)

4. T****rail Making Test–B (TMT–B)

***The tool for assessing comorbidities:***Charlson Comorbidity Index (CCI)

The tool for assessing frailty: Clinical Frailty Scale (CFS)

The tool for assessing postoperative complications: Clavien Dindo Complication Classification (CDCC)

Sample Size

Incidence of POCD in cancer surgeries at one week is 19 – 33%. Assuming 25% incidence in present study with 5% absolute margin of error either the side with 95% confidence level, a sample of 288 patients will be needed.

Data Interpretation

The data will be recorded in MS Excel spreadsheet program.

After the study, data analysis will be done, and the incidence with a 95% confidence interval shall be reported.

Chi-square and paired t-tests shall be used for the analysis of various baseline parameters for 7 days and 3 months.

Univariable and multivariable regression analysis will be performed to find the predictors of POCD. For secondary data analysis, we will use multiple logistic regression to investigate associations between risk factors on the neurocognitive tests 1 week and 3 months after the surgery.