Sociodemographic characteristics
A total of 384 patients were included in the study making a 100% response rate. Greater than half (57.8%) of the study participants were males and the rest, 162(42.2%) were females. Regarding the age of the participants, 170(44.3%) were aged between 65 and 74 years. Majorities, 312(81.3%) of the participants were married. With respect to educational status, greater than one-third (37.2%) of the study participant had no formal education (Table - 4).
Pre-operative Factors
As the distribution of pre-operative factors showed, ASA II held nearly three fourth (74.2%), of the ASA status of old-age patients, while ASA I and ASA III, were 84(21.9%) and 15(3.9%), respectively. Those patients who had a history of comorbid disease were 76(19.8%). Opioids were the frequently given premedication, 120(31.3%), followed by anti-cholinergics, 105(27.3%) and other premedication like diazepam and steroids, 95(24.7%). Regarding pre-operative hemoglobin levels, more than three-fourth (81.0%) of the old-age patients had normal hemoglobin levels, and the rest, 19.0% had low hemoglobin levels (anemic) (Table - 5).
Intra-operative and post-operative factors
Nearly greater than half (54.2%) of old-age patients were taken General Anesthesia. Among these 85(39.9%) of patients were induced with ketofol and the majority, (86.4%) were maintained with inhalational anesthetics in which nearly two-third (67.9%) of the patients were maintained by isoflurane. Regarding the duration of surgery, most procedures were longer than two hours, 314(81.8 %) (Table - 6).
Among the types of surgery old-age patients underwent, general surgeries were more frequently performed procedures relative to the other specialties, 98(25.5%) as described by the bar chart (Figure - 2).
Regarding the PACU sedation score, two-third (66.7) of old-age patients were calm and the rest were agitated, 36(9.4%), restless, 33(8.6%), combative, 32(8.3%) and very agitated, 27(7.0%) respectively, (Figure-3)
Magnitude of emergence delirium
The magnitude of emergence delirium in old-age patients who underwent elective surgery at Teaching Hospitals of Ethiopia was 106 (27.6%).
Factors Associated with Emergence Delirium among old-age patients who underwent elective surgery at PACU
Bivariable and multivariable logistic regression of factors associated with emergence delirium in old-age patients who underwent elective surgery at Teaching Hospitals of Ethiopia
Bivariable logistic regression was fitted to identify candidate variables for the multivariable logistic regression. Accordingly, educational status, marital status, premedication with opioids and anti-cholinergics, comorbidity, pre-operative hemoglobin level, types of anesthesia, maintenance agent, post-operative pain, and post-operative sedation were associated to ED at p-value of < 0.25 (Table-7)
Factors independently associated with emergence delirium in old-age patients who underwent elective surgery at Teaching Hospitals of Ethiopia
Multivariable logistic regression was fitted to identify factors independently associated with emergence delirium. Accordingly, pre-operative low Hgb level, premedication of opioids and anti-cholinergics and moderate to severe post-operative pain at PACU were significantly associated with emergence delirium in multivariable logistic regression at p-value of <0.05.
Old-age patients who had given opioid premedication were 8 times (AOR: 8.0, 95%CI: 3.22 – 27.8), more likely to develop emergence delirium as compared to those patients who were not given opioid premedication. On the other hand, old-age patients who had anti-cholinergic premedication were 8.5 times (AOR: 8.5, 95%CI: 8.5(6.85 – 17.35), more likely to develop emergence delirium as compared to those who were not given anti-cholinergic premedication.
Old-age patients who had low pre-operative hemoglobin were 2 times (AOR; 2.0, 95% CI, 1.77 – 3.46), more likely to develop emergence delirium as compared to those who had normal hemoglobin. Those old-age patients experiencing moderate to severe pain at PACU were 3.10 times (AOR; 3.10, 95% CI, 2.07 – 9.84), more likely to develop emergence delirium as compared to old-age patients experiencing mild pain (Table- 8)