Study of perioperative hemodynamic parameters in elderly patients undergoing hip surgery under spinal anesthesia: Comparison between frail and non-frail groups

Frailty is defined as a state of vulnerability due to reduced physiological reserve that predisposes the patients to adverse outcomes from different types of stress including surgery. Frailty is measured by frailty index (FI). The principle of this index is to count the deficits in health (which can be symptoms, signs, diseases, disabilities or laboratory, radiographic or electrocardiographic abnormalities). The index is expressed as a ratio of deficits present to the total number of deficits considered. FI<0.12 is considered non frail, 0.12-0.24 is considered mild frail, 0.24- 0.36 is moderate frail and index more than 0.36 is regarded as severely frail. Intra-operative complication that occurs most commonly in the frail patients includes hypotension that requires vasopressor or blood transfusion. Evidence on intraoperative hemodynamic instability in frail patients is particularly limited.

After approval of CTRI, all elderly patients (age>65-85 years) planed for unilateral hip surgery under spinal anesthesia over the next one year will undergo pre anesthetic check up by history taking, clinical examinations and investigations. National Early Warning Score (NEWS) will be assessed in each patient depending on the clinical examination. Patients having score <5 will be assessed for eligibility. Frailty index (FI) will be calculated based on the deficits (Table 2). Depending on the FI value, patients will be allocated in three groups after written informed consent; Group NF (Non-frail), group MiF (mild frail) and group MoF (moderate frail).

In all patient subarachnoid block will be performed at L3-4 or L4-5 inter space in sitting position with 0.5% hyperbaric bupivacaine (1.5 ml) and fentanyl 25 mcg. Intraoperative MAP, HR and ST changes will be compared at every 3 min interval for 30 min, thereafter at 5 min interval till the end of surgery. Post operatively vitals will be recorded at 30 min interval for 6 hours. Incidence of hypotension, bradycardia or other complications will be recorded.

As there is no previous study comparing hemodynamic changes in different types of frail patients, outcome will be evident only after the completion of the study.