Preoperative and Postoperative Oxygen Saturation in the Elderly following Spinal or General Anaesthesia—An Audit of Current Practice

Abstract

We have compared the incidence of preoperative and postoperative oxygen desaturation in 20 elderly patients undergoing dynamic hip screw insertion for fractured neck of femur, allocated randomly to two groups to receive subarachnoid anaesthesia (SA, n = 10) or a general anaesthetic (GA, n = 10). Oximetry data were recorded during the preoperative night and the first 48 hours after surgery using Satmaster. 1\1 Data associated with zero amplitude signal were automatically invalidated by the software and decreases in Sp02 which were preceded by contemporaneous changes in signal amplitude which conformed to a previously described template were assumed to be artefactual and were discarded from final data analysis. Data demonstrated a wide interpatient variability. However, those patients who desaturated preoperatively continued to do so in the postoperative period. The differences between the preoperative and postoperative oximetry profiles were examined for each patient and demonstrated a significantly longer time spent with Sp02 <90% in the GA group compared with the SA group, in all the recorded time periods, except on the day of surgery. The SA group showed an improvement in oxygen saturation postoperatively when compared to the preoperative night, spending less time with an Sp02 <85%. We conclude that the subarachnoid anaesthetic technique was associated with a lower incidence of postoperative oximetry desaturation when compared with general anaesthetic for these elderly patients undergoing repair of fractured neck of femur.

Heart rate variability as a predictor of hypotension after spinal anesthesia in hypertensive patients

“…Hypotension, the most common side effect after spinal anesthesia [1], occurs more frequently in geriatric patients with hypertension [2,3]. Decrease in systemic vascular resistance by sympathetic blockades is one of the major mechanism responsible for hypotension after a spinal block [4].…”

Neuroaxial versus general anaesthesia in geriatric patients for hip fracture surgery: does it matter?

“…Three citations were considered to provide Level I evidence. Many studies included a small number of patients and only few outcome parameters: there were 12 RCTs with a sample size of ≤40 patients [21,[25][26][27][28][29][30][31][32][33][34][35]. The study by McKenzie et al [36] involves one study population, whereas the other two studies by McKenzie et al [33,37] identified only subgroups of these patients.…”

“…Perioperative respiratory outcome was reported either as hypoxia [2,5,7,27,45] or as arterial carbon dioxide partial pressure, arterial oxygen partial pressure and/or oxygen saturation [36,39,55,61]. Patients with regional anaesthesia do not undergo airway instrumentation.…”

“…Hence, they have a lesser risk for hypoxia [75]. However, only the early postoperative period following regional anaesthesia for hip fracture repair is superior with regard to the incidence of postoperative hypoxia as seen in arterial oxygen tensions or clinically (evidence level I-III; I: n=2) [2,5,7,27,36,37,45]. Therefore, some authors reported no significant difference between the techniques (evidence level I-III; I: n=1) [39,48,55,56,61,68].…”

Crystalloid and colloid preload for maintaining cardiac output in elderly patients undergoing total hip replacement under spinal anesthesia

“…Studies have shown that regional anesthesia for total hip replacement results in better postoperative outcomes, including improved respiratory function, less nausea and vomiting, less pain, and lower incidence of deep vein thrombosis[6]–[8]. Among regional anesthetic techniques, spinal anesthesia has become the preferred technique because it offers a fast, profound, and high quality sensory and motor block with reduced risk of local anesthetic toxicity.…”