Introduction
lethargy, Postoperative delirium, delirium, comorbidity, neurocognitive dysfunction, sleeplessness, cognitive impairment, metabolic derangements, infections, postoperative agitation, pain, hearing impairment, fractures, Delirium, hallucination, apathy
DRUG WITHDRAWAL, INFECTIONS, HEARING IMPAIRMENT, PND, COMPLICATIONS
After surgery, elderly people often have symptoms such as postoperative agitation uncontrolled movement, nonsense, placement or orientation issue, hallucination, sleeplessness or lethargy, apathy, and so on. These symptoms imply that the patients may suffer from perioperative neurocognitive dysfunction (PND). However, it may have an impact on patients' life quality and poor organ functional recovery following surgery, leading to an increase in mortality [Postoperative delirium (POD), one of PND, occurs during the surgical recovery period, so it complicates postoperative care and introduces new hazards, such as aggressive fluid removal and fractures caused by falls, which increase the load on hospital resources and the family. Delirium can contribute to prolonged length of stay, readmission rates, increased institutional discharge, and ultimately, high resource utilization [Delirium is more common in older patients after surgery, so preventing and treating POD is a pressing clinical issue. Delirium is multicausal. Previous studies on delirium pointed out old age, cognitive impairment, medical comorbidity, institutional residence, psychotropic drug, visual and hearing impairment are most predisposing risk factors, while admission to ICU, anticholinergic drugs, alcohol or drug withdrawal, infections, iatrogenic complications, metabolic derangements and pain are most precipitating factors [Hence, the current research was planned to look into the impact of DEX given by PCIA on POD in elderly patients after major thoracoabdominal surgery. We anticipated that DEX given through PCIA 1–3 days after surgery might prevent POD in older patients.