Prevalence of Delirium in Elderly Postoperative Patients with Hip Fractures

Abstract Background: Delirium can be defined as a rapid decline in neurocognitive function, presenting as altered consciousness or changes in attention that cannot be explained by a pre-existing neurocognitive disorder. Post-operative delirium is a major health concern in elderly patients. Delirium can be of 3 types: hyperactive delirium, hypoactive delirium, and mixed delirium [1] The exact reason for development of post-operative delirium is not clearly understood. Some of the widely accepted theories are based on involvement of neuroinflammation, neurotransmitters, and metabolic abnormality. [2] Methodology: An observational study was conducted at Vydehi Institute of Medical Sciences and Research Centre on elderly patients undergoing surgery for hip fractures. All patients were evaluated preoperatively and postoperatively using a standardised delirium assessment tool—the Confusion Assessment Method. In addition, demographic details, comorbidities, and type of anaesthesia were collected and statistically analysed. Results: Delirium was almost three times more likely to occur in patients 75 years of age or older. Additionally, a BMI of ≥ 24 kg/m² was linked to roughly twice the risk. The odds were nearly doubled for a history of delirium. Notable surgical factors included an estimated blood loss of 400 mL or more and a surgery time of 120 minutes or more, both of which approximately doubled the risk of delirium. TSH ≤ 2 mU/L and albumin ≤ 40 g/L were linked to higher odds among laboratory markers, each of which conferred a risk that was roughly 1.8–2.0 times higher. Significant independent risk factors for postoperative delirium included advanced age, a higher body mass index, a history of delirium, a greater surgical burden, and particular biochemical abnormalities. Hypertension, diabetes mellitus, hyponatremia, and hypokalemia were among the medical conditions that were substantially more prevalent in the delirium group. Additionally, patients who experienced delirium during this admission were significantly more likely to have a history of delirium. There were no appreciable differences between the groups in the kinds of fractures or anaesthesia techniques. In terms of surgical variables, delirious patients experienced longer surgery times and higher estimated blood loss than non-delirious patients. Time to surgery and pre-operative ADL scores were comparable across groups. The development of postoperative delirium may be linked to the delirium group's overall higher burden of comorbidities, more invasive or prolonged surgery, and greater electrolyte abnormalities. Conclusion: Through our study we can conclude that elderly patients have a higher risk of experiencing post-operative delirium and the risk increases along with the severity of comorbidities. The cause for the same is mostly linked to BMI, blood pressure, TSH, blood loss intra-operatively and duration of surgery.