Postoperative infusion of dexmedetomidine for the prevention of postoperative delirium in elderly patients undergoing lung surgery: A randomized controlled trial.

This systematic review and meta-analysis aimed to evaluate the preventive effect of transcutaneous electrical acupoint stimulation on postoperative delirium in elderly surgical patients. PubMed, CENTRAL, China National Knowledge Infrastructure, and WanFang databases were searched for randomized controlled trials regarding the effect of transcutaneous electrical acupoint stimulation on preventing postoperative delirium in elderly patients undergoing any type of surgery. The primary outcome was the incidence of postoperative delirium. The secondary outcome was the duration of postoperative delirium. All analyses were conducted using RevMan 5.3 and Stata 13.0 software. Twelve trials with 991 participants were included, and most of them were at high/unclear risk of bias. Meta-analysis showed transcutaneous electrical acupoint stimulation could reduce the incidence of postoperative delirium (RR = 0.40, 95%CI = 0.29 to 0.55, p < 0.00001) and shorten the duration of postoperative delirium (MD = -0.97 days, 95%CI = -1.72 to -0.22, p = 0.01). Subgroup analyses demonstrated that transcutaneous electrical acupoint stimulation reduced the incidence of postoperative delirium in elderly patients undergoing orthopedic surgery and thoracic surgery, but not digestive surgery; transcutaneous electrical acupoint stimulation with dilatational wave and with continuous wave were both beneficial; and transcutaneous electrical acupoint stimulation was favored when compared to blank and sham control. Transcutaneous electrical acupoint stimulation could reduce the incidence of postoperative delirium and shorten the duration of postoperative delirium in elderly surgical patients. The findings should be interpreted with caution due to weak evidence. High-quality, large sample, and multi-center trials are needed to further confirm the preliminary findings.Systematic review registration: https://inplasy.com/inplasy-2022-7-0096/, identifier: INPLASY202270096.

Introduction: Vulnerable or “frail” patients are susceptible to the development of delirium when exposed to triggers such as surgical procedures. Once delirium occurs, interventions have little effect on severity or duration, emphasizing the importance of primary prevention. This review provides an overview of interventions to prevent postoperative delirium in elderly patients undergoing elective surgery.Methods: A literature search was conducted in March 2018. Randomized controlled trials (RCTs) and before-and-after studies on interventions with potential effects on postoperative delirium in elderly surgical patients were included. Acute admission, planned ICU admission, and cardiac patients were excluded. Full texts were reviewed, and quality was assessed by two independent reviewers. Primary outcome was the incidence of delirium. Secondary outcomes were severity and duration of delirium. Pooled risk ratios (RRs) were calculated for incidences of delirium where similar intervention techniques were used.Results: Thirty-one RCTs and four before-and-after studies were included for analysis. In 19 studies, intervention decreased the incidences of postoperative delirium. Severity was reduced in three out of nine studies which reported severity of delirium. Duration was reduced in three out of six studies. Pooled analysis showed a significant reduction in delirium incidence for dexmedetomidine treatment, and bispectral index (BIS)-guided anaesthesia. Based on sensitivity analyses, by leaving out studies with a high risk of bias, multicomponent interventions and antipsychotics can also significantly reduce the incidence of delirium.Conclusion: Multicomponent interventions, the use of antipsychotics, BIS-guidance, and dexmedetomidine treatment can successfully reduce the incidence of postoperative delirium in elderly patients undergoing elective, non-cardiac surgery. However, present studies are heterogeneous, and high-quality studies are scarce. Future studies should add these preventive methods to already existing multimodal and multidisciplinary interventions to tackle as many precipitating factors as possible, starting in the pre-admission period.

BackgroundPostoperative delirium is a frequent complication in elderly patients undergoing major abdominal surgery and is associated with a poor outcome. We compared postoperative delirium in elderly patients following laparoscopic gastrectomy (LG) versus open gastrectomy (OG).MethodsIn total, 130 patients aged ≥ 65 years with gastric cancer undergoing LG and OG were enrolled prospectively. Postoperative delirium and cognitive status were assessed daily using the Confusion Assessment Method (CAM) and Mini-Mental Status Examination (MMSE), respectively, for 3 days postoperatively. For CAM-positive patients, delirium severity was then assessed using the Delirium Index (DI).ResultsIn total, 123 subjects (LG, n = 60; OG, n = 63) were included in the analysis. In both groups, the overall incidences of postoperative delirium were similar: 31.6% (19/60) in the LG group and 41.2% (26/63) in the OG group. When considering only those with delirium, the severity, expressed as the highest DI score, was similar between the groups. A decline in cognitive function (reduction in MMSE ≥ 2 points from baseline) during 3 days postoperatively was observed in 23 patients in the LG group (38.3%) and 27 patients in the OG group (42.9%) (P = 0.744). In both groups, postoperative cognitive decline was significantly associated with postoperative delirium (P < 0.001).ConclusionsWe found that, compared with traditional open gastrectomy, laparoscopic gastrectomy did not reduce either postoperative delirium or cognitive decline in elderly patients with gastric cancer.

Postoperative delirium, particularly prevalent in elderly patients after abdominal cancer surgery, presents significant challenges in clinical management. To develop a synthetic minority oversampling technique (SMOTE)-based model for predicting postoperative delirium in elderly abdominal cancer patients. In this retrospective cohort study, we analyzed data from 611 elderly patients who underwent abdominal malignant tumor surgery at our hospital between September 2020 and October 2022. The incidence of postoperative delirium was recorded for 7 d post-surgery. Patients were divided into delirium and non-delirium groups based on the occurrence of postoperative delirium or not. A multivariate logistic regression model was used to identify risk factors and develop a predictive model for postoperative delirium. The SMOTE technique was applied to enhance the model by oversampling the delirium cases. The model's predictive accuracy was then validated. In our study involving 611 elderly patients with abdominal malignant tumors, multivariate logistic regression analysis identified significant risk factors for postoperative delirium. These included the Charlson comorbidity index, American Society of Anesthesiologists classification, history of cerebrovascular disease, surgical duration, perioperative blood transfusion, and postoperative pain score. The incidence rate of postoperative delirium in our study was 22.91%. The original predictive model (P1) exhibited an area under the receiver operating characteristic curve of 0.862. In comparison, the SMOTE-based logistic early warning model (P2), which utilized the SMOTE oversampling algorithm, showed a slightly lower but comparable area under the curve of 0.856, suggesting no significant difference in performance between the two predictive approaches. This study confirms that the SMOTE-enhanced predictive model for postoperative delirium in elderly abdominal tumor patients shows performance equivalent to that of traditional methods, effectively addressing data imbalance.

Delirium is a frequent postoperative complication in elderly patients after non-cardiac surgery. We performed this updated meta-analysis to ascertain more precisely the efficacy of dexmedetomidine (DEX) on the incidence of postoperative delirium (POD) in elderly patients after non-cardiac surgery. We searched PubMed, EMBASE, the Cochrane Library, Web of Science, and the Cumulative Index of Nursing and Allied Health Literature (CINAHL)from inception until February 24, 2019. In this meta-analysis, we included randomized-controlled trials comparing the effect of DEX vs normal saline (NS) or other anesthetic drugs on POD incidence in elderly (either ≥ 60 or ≥ 65 yr old) patients undergoing non-cardiac surgery. We performed subgroup analyses of the DEX dosing strategy (starting time, dose, and duration of administration, with or without loading dose) and the strategy of various control drugs. A random-effects model was used for all analyses. We included 11 studies involving 2,890 patients in our meta-analysis. The pooled results of these studies revealed that DEX significantly reduced the incidence of POD (relative risk [RR], 0.47; 95% confidence interval [CI], 0.38 to 0.58; P < 0.001) compared with the control group. Meanwhile, the incidences of hypotension (RR, 1.20; 95% CI, 1.04 to 1.39; P = 0.01) and bradycardia (RR, 1.33; 95% CI, 1.08 to 1.63; P = 0.007) were increased in the DEX group. Subgroup analyses revealed a decrease in POD incidence when DEX was administered intraoperatively (RR, 0.43; 95% CI, 0.33 to 0.57; P < 0.001) and postoperatively (RR, 0.38; 95% CI, 0.27 to 0.54; P < 0.001) with a loading dose (RR, 0.49; 95% CI, 0.36 to 0.69; P < 0.001) compared with NS (RR, 0.49; 95% CI, 0.37 to 0.64; P < 0.001) and other anesthetic drugs (RR, 0.40; 95% CI, 0.26 to 0.60; P < 0.001). There were significant differences in the time to extubation (standardized mean difference, -0.60; 95% CI, -1.17 to -0.03; P = 0.04) and the length of hospital stay (mean difference, -0.50 days; 95% CI, -0.97 to -0.03; P = 0.04). The amount of data for the duration of mechanical ventilation and length of intensive care unit stay were insufficient to perform a meta-analysis. Perioperative dexmedetomidine reduces the incidence of POD in elderly patients after non-cardiac surgery, but this comes at the cost of an increased incidence of hypotension and bradycardia.

Intravenous dexmedetomidine has been reported to decrease the occurrence of postoperative delirium (POD) in elderly patients. Nevertheless, some previous studies have indicated that intratracheal dexmedetomidine and intranasal dexmedetomidine are also effective and convenient. The current study aimed to compare the effect of different administration routes of dexmedetomidine on POD in elderly patients. We randomly allocated 150 patients (aged 60 years or more) scheduled for spinal surgery to receive intravenous dexmedetomidine (0.6 μg/kg), intranasal dexmedetomidine (1 μg/kg) before anesthesia induction, or intratracheal dexmedetomidine (0.6 µg/kg) after anesthesia induction. The primary outcome was the frequency of delirium during the first 3 postoperative days. The secondary outcomes were the incidence of postoperative sore throat (POST) and sleep quality. Adverse events were recorded, and routine treatment was performed. Compared with the intranasal group, the intravenous group had a significantly lower occurrence of POD within 3 days (3 of 49 [6.1%] vs 14 of 50 [28.0%]; odds ratio [OR], 0.17; 95% confidence intervals [CIs], 0.05-0.63; P < .017). Meanwhile, patients in the intratracheal group had a lower incidence of POD than those in the intranasal group (5 of 49 [10.2%] vs 14 of 50 [28.0%]; OR, 0.29; 95% CI, 0.10-0.89; P < .017). Whereas, there was no difference between the intratracheal and intravenous groups (5 of 49 [10.2%] vs 3 of 49 [6.1%]; OR, 1.74; 95% CI, 0.40-7.73; P > .017). The rate of POST was lower in the intratracheal group than that in the other 2 groups at 2 hours after surgery (7 of 49 [14.3%] vs 12 of 49 [24.5%] vs 18 of 50 [36.0%], P < .017, respectively). Intravenous dexmedetomidine had the lowest Pittsburgh Sleep Quality Index score on the second morning after surgery (median [interquartile range {IQR}]: 4 [3-5] vs 6 [4-7] vs 6 [4-7], P < .017, respectively). Compared with the intranasal group, the intravenous group had a higher rate of bradycardia and a lower incidence of postoperative nausea and vomiting (P < .017). The intranasal group was associated with the highest incidence of hypertension (P < .017). For patients aged ≥60 years undergoing spinal surgery, compared with the intranasal route of dexmedetomidine, intravenous and intratracheal dexmedetomidine reduced the incidence of early POD. Meanwhile, intravenous dexmedetomidine was associated with better sleep quality after surgery, and intratracheal dexmedetomidine resulted in a lower incidence of POST. Adverse events were mild in all 3 administration routes of dexmedetomidine.

Introduction: We analyzed the effect of dexmedetomidine (DEX) as a local anesthetic adjuvant on postoperative delirium (POD) in elderly patients undergoing elective hip surgery. Methods: In this study, 120 patients undergoing hip surgery were enrolled and randomly assigned to two groups: fascia iliaca compartment block with DEX + ropivacaine (the Y group, n = 60) and fascia iliaca compartment block with ropivacaine (the R group, n = 60). The primary outcomes: presence of delirium during the postanesthesia care unit (PACU) period and on the first day (D1), the second day (D2), and the third day (D3) after surgery. The secondary outcomes: preoperative and postoperative C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR), occurrence of insomnia on the preoperative day, day of operation, D1 and D2; HR values of patients in both groups before iliac fascia block (T1), 30 min after iliac fascia block (T2), at surgical incision (T3), 20 min after incision (T4), when they were transferred out of the operating room (T5) and after leaving the recovery room (T6) at each time point; VAS for T1, PACU, D1, D2; the number of patients requiring remedial analgesics within 24 h after blockade and related complications between the two groups. Results: A total of 97 patients were included in the final analysis, with 11 and 12 patients withdrawing from the R and Y groups, respectively. The overall incidence of POD and its incidence in the PACU and ward were all lesser in the Y group than in the R group (p < 0.05). Additionally, fewer cases required remedial analgesia during the PACU period, and more vasoactive drugs were used for maintaining circulatory system stability in the Y group as compared to the R group (p < 0.05). At the same time, the incidence of intraoperative and postoperative bradycardia in the Y group was higher than that in the R group, accompanied by lower postoperative CRP and ESR (all p < 0.05). Conclusion: Ultrasound-guided high fascia iliaca compartment block with a combination of ropivacaine and DEX can reduce the incidence of POD, the use of intraoperative opioids and postoperative remedial analgesics, and postoperative inflammation in elderly patients who have undergone hip surgery, indicating that this method could be beneficial in the prevention and treatment of POD.

Objective To investigate the effects of dexmedetomidine on postoperative delirium in elderly patients undergoing total hip arthroplasty. Methods A total of 100 patients, 42 male and 58 female, ages 60 to 85 years, American Society of Anesthesiologists grade I or II, who were undergoing total hip arthroplasty were randomly divided into 2 groups: a dexmedetomidine group (group D; n = 50) and a control group (group C; n = 50). Group D patients were infused with 0.3 μg · kg−1 · h−1 of dexmedetomidine from 5 minutes prior to anesthesia induction until the end of surgery. Group C patients received an equal volume of saline. Heart rate and mean arterial pressure (MAP) were recorded before anesthesia induction (T0), 1 minute before extubation (T1), and 30 minutes after extubation (T2). The Visual Analog Score (VAS) at 1, 2, and 3 days after surgery, the incidence and duration of postoperative delirium, and the length of hospital stay were recorded. Adverse reactions, such as nausea, vomiting, and lethargy, were also recorded. Results The Visual Analog Scores in the 2 groups were similar. In group D, there was no significant difference in heart rate (P = 0.232) and MAP (P = 0.056) between T0 and T1. However, in group C, heart rate significantly increased by 15.3 bpm (P = 0.000) and MAP significantly increased by 10.7 mmHg (P = 0.001) at T1 compared with those at T0. The incidence of postoperative delirium in group D (10%) was significantly lower than that in group C (26%; P = 0.037). The duration of delirium in group D (1.3 ± 0.6 days) was shorter than that in group C (3.0 ± 0.5 days; P = 0.000). The length of hospital stay in group D (13.2 ± 0.9 days) was shorter than that in group C (16.1 ± 0.7 days; P = 0.000). No significant differences were observed in adverse effects between the 2 groups. Conclusion Intravenous infusion of dexmedetomidine can not only reduce the incidence and duration of postoperative delirium, but also shorten the length of hospital stay in elderly patients undergoing total hip arthroplasty.

ObjectiveThe primary goal was to investigate whether the presence of preoperative lacunar infarcts (LACI) was associated with postoperative delirium (POD) in elderly patients undergoing elective major abdominal surgery.DesignA prospective cohort study.Setting and participantsPatients aged ≥ 65 years from a tertiary level A hospital in China.MethodsThe POD was assessed once daily within the first postoperative 3 days using the Confusion Assessment Method. Neurocognitive tests using the Mini-mental State Examination (MMSE) and the Beijing version of the Montreal Cognitive Assessment scales were carried out within 3 days before surgery and 4–7 days after surgery. Regional cerebral oxygen saturation (rScO2) was recorded in the operating room. Logistic regression analysis was used to evaluate the impact of preoperative LACI on POD and to explore the risk factors for POD.ResultsA total of 369 participants were analyzed, 161 in the preoperative LACI-positive group (P group), and 208 in the preoperative LACI-negative group (N group), respectively. The incidence of POD was 32.7% in our study. The incidence of POD was significantly higher in the P group than in the N group (39.1 vs 27.9%, risk ratio, 1.66; 95% CI 1.07–2.58; P = 0.022). Furthermore, the P group exhibited lower mean rScO2 values during the procedure (P < 0.001). In exploratory analysis, the advanced age (P = 0.005), sex (P = 0.038), and lower preoperative MMSE score (P = 0.019) were independent risk factors for POD in patients undergoing major abdominal surgery.Conclusions and implicationsPreoperative LACI was common, and constituted a risk factor for POD in older patients undergoing abdominal surgery. Despite the frequent subclinical nature, the preoperative LACI led to lower mean rScO2 during the procedure. These findings could help early identification of high-risk POD patients.

We read with great interest the randomized controlled trial by Chen et al investigating the effect of ciprofol on postoperative delirium (POD) in elderly patients undergoing hip surgery. 1 The study provides valuable insights into the potential benefits of ciprofol over propofol in reducing POD incidence and its correlation with SIRT3 expression.However, we have several methodological concerns that may affect the interpretation of the results and warrant further clarification.First, a major methodological concern in this study is the inadequate control for established confounding variables that significantly influence POD risk.Although basic demographic and intraoperative measures were reported, the authors did not provide comparative data on key preoperative comorbidities-such as hypertension, diabetes, coronary artery disease, atrial fibrillation, or history of stroke-all of which are risk factors for POD. 2,3Furthermore, although both groups received identical multimodal analgesia protocols-including regional nerve blocks and patient-controlled intravenous analgesia-systematic assessment of postoperative pain using validated scales (e.g, VAS or NRS) was lacking.Postoperative pain is a strong precipitant of delirium, particularly in elderly patients undergoing major orthopedic surgery.It may contribute to POD through mechanisms such as sleep disruption, anxiety, and systemic inflammatory activation. 4It is noteworthy that the reduction in POD incidence in the ciprofol group was most pronounced on postoperative day 1, which coincides with the period of highest pain intensity.This temporal association raises the possibility that the observed difference in POD incidence may be attributable to imbalances in patient vulnerability or analgesic efficacy rather than a direct neuroprotective effect of ciprofol.Therefore, we recommend that the authors provide detailed between-group comparisons of preoperative comorbidities and pain scores, and perform multivariate regression analyses adjusting for these potential confounders.Only through rigorous control of these variables can a more reliable causal relationship between ciprofol and reduced POD risk be established.Second, the predictive value of SIRT3 should be interpreted with caution.The reported AUCs were based on very few outcome events-10 delirium cases on postoperative day 1 and only 4 cases on day 3.Such small numbers lead to unstable estimates and wide confidence intervals (95% CI: 0.6968-1.000 on day 1), limiting the precision of the analysis.The finding on day 3, with a higher point estimate (AUC 0.8703) but no statistical significance (P>0.05),further reflects the lack of power inherent in such a limited dataset.Moreover, these analyses were conducted using univariate regression without adjustment for other known risk factors of delirium, leaving the possibility of confounding.The proposed cut-off value of 1.565 ng/mL, derived from this small sample, is also unlikely to be reliable and would require validation in independent cohorts.Taken together, the current results suggest that SIRT3 remains an interesting candidate biomarker, but its predictive role should be regarded as preliminary until confirmed in larger studies with sufficient events and multivariable adjustment.

PurposeThis study aimed to evaluate the effect of intraoperative intravenous (IV) lidocaine on the incidence of postoperative delirium (POD) in elderly patients undergoing major spinal surgery.Patients and MethodsIn this prospective, single-center randomized clinical trial, elderly patients scheduled for elective posterior lumbar interbody fusion (PLIF) with instrumentation spanning two or more vertebral segments were enrolled. A total of 270 patients were randomized to receive either intravenous lidocaine (Group L) or saline (Group C). Group L received lidocaine at a bolus dose of 1.5 mg/kg before induction, followed by continuous infusion at 1.5 mg/kg/h until the end of surgery, while Group C received an equivalent volume of saline. All patients underwent standardized general anesthesia. The primary outcome was the incidence of postoperative delirium (POD) within 5 days after surgery. Secondary outcomes included delirium severity, onset, duration, and subtype (hypoactive, hyperactive, or mixed), postoperative visual analog scale (VAS; 0–100 mm) pain scores, intraoperative anesthetic consumption, 24-hour sufentanil consumption and patient-controlled intravenous analgesia (PCIA) attempts, and perioperative adverse events.ResultsThe lidocaine group had a lower incidence of postoperative delirium (8.9% vs 20.7%; RR, 0.43; 95% CI, 0.23–0.81; P < 0.05). Among patients who developed delirium, the duration was comparable between groups, while severity scores were higher and time to onset was shorter in the control group. Within the first 24 hours postoperatively, the lidocaine group had lower VAS scores, fewer PCIA attempts, and a reduced cumulative sufentanil dose. Opioid-related adverse events, including nausea and vomiting, were less frequent, with no cases of local anesthetic toxicity, and the overall hospital stay was comparable.ConclusionIn elderly patients undergoing PLIF, intraoperative intravenous lidocaine (1.5 mg/kg administered before induction, followed by continuous infusion at 1.5 mg/kg/h until the end of surgery) lowered the occurrence of postoperative delirium (POD) within the first 5 days after surgery.

: This study evaluated the incidence of postoperative delirium (POD) in elderly patients undergoing general surgery, the risk factors associated with POD, and its impact on hospital stay and mortality. : Patients aged over 65 years who had emergency or elective operations were eligible for this case-control study. Risk factors significantly associated with POD using univariable analysis were entered into multivariable analysis, to establish those independently associated with POD. : A total of 351 patients (357 admissions) were enrolled in the study. The incidence of POD was 13.2 per cent (17.9 per cent for emergency operations). Independent variables associated with POD were: age above 75 years, co-morbidity, preoperative cognitive impairment, psychopathological symptoms and abnormal glycaemic control. Median length of hospital stay was 21 (range 1-75) days for patients with POD versus 8 (range 1-79) days for control patients (P < 0.001). The hospital mortality rate was 19 and 8.4 per cent respectively (P = 0.021). : The incidence of POD is high in elderly patients for both emergency and elective surgery, leading to an increase in hospital stay and perioperative mortality. To minimize POD, associated risk factors of co-morbidity, cognitive impairment, psychopathology and abnormal glycaemic control must be identified and treated.

AimThe aim of the present study was to investigate the occurrence of postoperative delirium (POD) in elderly patients undergoing transurethral resection of prostate (TURP) and to identify those factors associated with delirium.MethodsFrom July 2010 to February 2015, 358 patients, aged ≥65 years and undergoing TURP were prospectively enrolled. Personal, medical and cognitive data, laboratory assessments, pain intensity, preoperative medications, and details of hemodynamic control were collected as predictors of delirium. POD was assessed using the Confusion Assessment Method.ResultsIn the present study, POD occurred in 28 out of 358 cases (7.8%) after TURP, with duration of 1–4 days. The multivariate analysis showed that old age and visual analog scale pain scores were associated with POD. Marital status, body mass index, education, alcohol consumption, smoking history, preoperative psychotropic medication usage, activities of daily living scores, preoperative Mini-Mental Status Examination score, anesthesia type, American Society of Anesthesiologists classification, or hypotensive episodes during surgery did not significantly correlate with the occurrence of POD.ConclusionOld age and pain intensity after surgery were found as the risk factors for the development of delirium in elderly patients undergoing TURP. These findings might help develop preventive strategies to decrease POD through targeted evaluation.

Delirium is an acute cognitive change characterized by behavioral and psychological features, such as visual and auditory hallucinations, sleep disturbances, and emotional confusion. It can lead to extended hospital stays, increased mortality risk, and higher nursing costs. In postoperative hip fracture patients, delirium results in a higher complication rate, poorer functional recovery, increased readmission rates, repeat surgeries, and elevated mortality. Despite these serious consequences, the literature provides limited information on the incidence of postoperative delirium following hip fracture surgeries in Asians. Additionally, there is a lack of long-term, comprehensive nationwide population-based studies, highlighting an important area for future research. This study aims to understand the incidence and risk factors of postoperative delirium in hip fracture patients using representative population data. We conducted a retrospective cohort study using the Taiwan National Health Insurance Research Database (NHIRD) from 2009 to 2020. The cohort consisted of 118,682 patients aged 65years or older who were diagnosed with hip fractures. The delirium incidence was observed per 1000 person-years. The Cox proportional hazards model was used to investigate the incidence of delirium among hip fracture patients. The incidence of the first episode of delirium after hip surgery in the elderly was 1.87 events per 1000 PYs. Factors associated with delirium included being female (adjusted hazard ratio [aHR]: 0.59; 95% confidence interval [CI]: 0.53-0.64), age ≥95years (aHR: 3.52; 95% CI: 2.74-4.51), comorbid dementia (aHR: 2.63; 95% CI: 2.38-2.92), and ICU stay 2-3days (aHR: 2.85; 95% CI: 1.28-6.37). The occurrence of delirium was significantly associated with an ICU stay of ≥4days, dementia, as well as 30-day, 90-day, and 1-year mortality (p<0.001). This study highlights the relatively low incidence of postoperative delirium in elderly hip fracture patients in Taiwan. Key risk factors identified include advanced age, female gender, comorbid dementia, and prolonged ICU stays. These findings underscore the need for targeted prevention and early intervention strategies to improve patient outcomes.

The reported incidence of postoperative delirium (POD) in elderly patients ranges from 6 to 53 %. Several preoperative and operative factors have been reported as risk factors of POD. The aim of this study was to determine the incidence of and risk factors for POD in patients with colorectal cancer who had undergone laparoscopic colorectal resection. A total of 311 consecutive patients aged 75 years and older who underwent laparoscopic surgery for colorectal cancer at our department from January 2008 to December 2013 were classified as delirious group (n = 44) and nondelirious group (n = 267). Short-term outcomes and risk factors for POD were analyzed. POD was diagnosed in 14.1 % of elderly patients with colorectal cancer. Univariate analysis showed that older age, high American Society of Anesthesiology (ASA) score, performance status >2, low prognostic nutrition index (PNI), past history of delirium or dementia, operative approach, Organ/Space SSI, and cardiac or pulmonary disease were significantly associated with POD. Multivariate logistic regression analysis identified older age, past history of delirium or dementia, operative approach, and Organ/Space SSI as four independent risk factors for POD. Our results suggest that the risk of POD is associated with older age, past history of delirium or dementia, operative approach, Organ/Space SSI.