Predictive modeling for postoperative delirium in elderly patients with abdominal malignancies using synthetic minority oversampling technique

BACKGROUND Postoperative delirium,particularly prevalent in elderly patients after abdominal cancer surgery,presents significant challenges in clinical management.AIM To develop a synthetic minority oversampling technique(SMOTE)-based model for predicting postoperative delirium in elderly abdominal cancer patients.METHODS 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.RESULTS 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.CONCLUSION 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.

Metabolomic Analysis in Saliva and Different Brain Regions of Older Mice with Postoperative Delirium Behaviors

Objective Postoperative delirium(POD)has become a critical challenge with severe consequences and increased incidences as the global population ages.However,the underlying mechanism is yet unknown.Our study aimed to explore the changes in metabolites in three specific brain regions and saliva of older mice with postoperative delirium behavior and to identify potential non-invasive biomarkers.Methods Eighteen-month-old male C57/BL6 mice were randomly assigned to the anesthesia/surgery or control group.Behavioral tests were conducted 24 h before surgery and 6,9,and 24 h after surgery.Complement C3(C3)and S100 calcium-binding protein B protein(S100beta)levels were measured in the hippocampus,and a metabolomics analysis was performed on saliva,hippocampus,cortex,and amygdala samples.Results In total,43,33,38,and 14 differential metabolites were detected in the saliva,hippocampus,cortex,and amygdala,respectively.“Pyruvate”“alpha-linolenic acid”and“2-oleoyl-1-palmitoy-snglycero-3-phosphocholine”are enriched in one common pathway and may be potential non-invasive biomarkers for POD.Common changes were observed in the three brain regions,with the upregulation of 1-methylhistidine and downregulation of D-glutamine.Conclusion Dysfunctions in energy metabolism,oxidative stress,and neurotransmitter dysregulation are implicated in the development of POD.The identification of changes in the level of salivary metabolite biomarkers could aid in the development of noninvasive diagnostic methods for POD.

Postoperative delirium:A tragedy for elderly cancer patients

In this editorial,we comment on the article by Hu et al entitled“Predictive modeling for postoperative delirium in elderly patients with abdominal malignancies using synthetic minority oversampling technique”.We wanted to draw attention to the general features of postoperative delirium(POD)as well as the areas where there are uncertainties and contradictions.POD can be defined as acute neurocognitive dysfunction that occurs in the first week after surgery.It is a severe postoperative complication,especially for elderly oncology patients.Although the underlying pathophysiological mechanism is not fully understood,various neuroinflammatory mechanisms and neurotransmitters are thought to be involved.Various assessment scales and diagnostic methods have been proposed for the early diagnosis of POD.As delirium is considered a preventable clinical entity in about half of the cases,various early prediction models developed with the support of machine learning have recently become a hot scientific topic.Unfortunately,a model with high sensitivity and specificity for the prediction of POD has not yet been reported.This situation reveals that all health personnel who provide health care services to elderly patients should approach patients with a high level of awareness in the perioperative period regarding POD.

Correlation of preoperative inflammatory factors and emotional disorders with postoperative delirium in patients with craniocerebral trauma

BACKGROUND Traumatic brain injury(TBI)imposes a substantial societal and familial burden due to its high disability and fatality rates,rendering it a serious public health problem.Some patients with TBI have poor treatment outcomes and are prone to postoperative delirium(POD),which affects their quality of life.Anxiety has been linked to increased POD incidence in some studies,while others have found no correlation.AIM To investigate the correlation of POD risk factors,preoperative inflammatory factors,and mood disorders in patients with TBI.METHODS We retrospectively collected data on the treatment of 80 patients with TBI from November 2021 to September 2023.Patients were grouped as POD and non-POD,according to their POD status,and the general data of the two groups were compared.Inflammatory factor levels were detected preoperatively,and the Hamilton Depression Scale(HAMD)and Hamilton Anxiety Scale(HAMA)were used to investigate the risk factors associated with POD in these patients.Logistic regression was used to identify the independent risk factors.RESULTS Twenty-one patients(26.25%)developed POD,including 7,10,and 4 cases of the excitatory,inhibitory,and mixed types,respectively.There were 59 cases(73.75%)in the non-POD group.Compared with the non-POD group,the POD group had a significantly higher proportion of patients with low Glasgow Coma Scale(GCS)scores before admission,unilateral mydriasis,preoperative hemorrhagic shock,intraventricular hemorrhage(IVH),and postoperative hyperglycemic hyperosmolar disease(P<0.05).In the POD group,interleukin-6(IL-6),human tumor necrosis factor-α(TNF-α),myeloperoxidase levels,HAMA,and HAMD scores were higher than those in the non-POD group(all P<0.05).Logistic multivariate analysis showed that GCS score at admission,IVH,IL-6,TNF-α,HAMA,and HAMD were independent risk factors for POD in patients with TBI(P<0.05).CONCLUSION Low GCS score at admission,IVH,elevated IL-6 and TNF-α,other inflammatory indicators,anxiety,and depression,can increase the risk of POD in patients with TBI after surgery.

Implications of Elevated Serum Cortisol in the Onset of Postoperative Delirium Following Off-Pump Coronary Artery Bypass Grafting: Insights from a Bangladesh-Based Single Center Experience

Background: Following coronary artery bypass grafting (CABG), delirium emerges as a prevalent complication. This study aimed to assess the correlation between elevated serum cortisol levels and the occurrence of postoperative delirium subsequent to off-pump CABG. Methods: Conducted in the Department of Cardiac Surgery at BSMMU from October 2020 to September 2022, this comparative cross-sectional study included a total of 44 participants. Subjects, meeting specific criteria, were purposefully assigned to two groups based on off-pump CABG. Group A (n = 22) consisted of patients with normal serum cortisol levels, while Group B (n = 22) comprised individuals with high serum cortisol levels on the first postoperative day. Delirium onset was assessed at the bedside in the ICU on the 1st, 2nd, 3rd, 4th, and 5th postoperative days using standard tools, namely the Richmond Agitation Sedation score (RASS) and The Confusion Assessment Method (CAM-ICU). Data were collected based on the presence or absence of delirium. Statistical analysis utilized SPSS version 26.0, employing an independent Student’s t-test for continuous data and chi-square and Fischer’s exact test for categorical data. A p-value ≤ 0.05 was considered statistically significant. Results: Group-A had a mean age of 54.50 ± 17.97, and Group-B had a mean age of 55.22 ± 15.45, both with a male predominance (81.81% and 86.36% respectively). The mean serum cortisol level was significantly higher in Group B (829.71 ± vs. 389.98 ± 68.77). Postoperative delirium occurred in 27.3% of Group B patients, statistically significant compared to the 4.5% in Group A. However, patients in Group B who developed delirium experienced significantly longer postoperative ICU and hospital stays (79.29 ± 12.27 vs. 11.44 ± 2.85, p ≤ 0.05). There was one mortality in Group B, which was statistically not significant. Conclusion: This study observed a significant association between elevated serum cortisol levels in the postoperative period and the occurrence of postoperative delirium after off-pump coronary artery bypass grafting.

A nursing protocol targeting risk factors for reducing postoperative delirium in patients following coronary artery bypass grafting:Results of a prospective before-after study

Objective: The results of postoperative delirium (POD) warrant testing for prevention. The purpose of this study was to determine whether a nursing intervention targeting risk factors could decrease the inci-dence of POD among patients who had coronary artery bypass grafting (CABG) in China.Methods: A prospective before-after study was conducted between April 2014 and April 2015. A nursing delirium intervention protocol targeting risk factors for delirium was performed for 141 patients un-dergoing CABG in a cardiothoracic ICU from November 2014 to April 2015. Intervention consisted of screening for delirium risk factors, followed by targeted risk factor modification, including pain control, early catheter removal, patient orientation using the 5W1H procedure, increased family visits, mini-mizing care-related interruptions, comfortable nursing and monitoring for sleeping difficulties. Out-comes of the Intervention Group were compared with those of the Control Group for 137 CABG patients from April 2014 to October 2014. Delirium was assessed using the confusion assessment method for the intensive care unit (CAM-ICU). The sample size was justified by PASS2000, based on previous data of delirium incidence in our institution (30%). Main results: Delirium incidence during the first seven postoperative days was significantly lower in the Intervention Group at 13.48%(19/141) vs. 29.93%(41/137) for the Control Group (x2=11.112, P=0.001). In addition, POD in the Intervention Group occurred between the 3rd and 6th postoperative days, while POD in the Control Group mainly occurred on the first three days postoperatively. Delirium in the Intervention Group occurred later than delirium in the Control Group (x2=12.743, P<0.001). Length of ICU stay was reduced significantly (Z= -6.026, P<0.001). Conclusion: The application of a nursing protocol targeting risk factors in this study seems to be asso-ciated with a lower incidence of POD in patients after CABG. This finding suggests that managing the predictors properly is one of the effective strategies to prevent delirium.

Effects of perioperative rosuvastatin on postoperative delirium in elderly patients:A randomized,double-blind,and placebo-controlled trial

BACKGROUND Experimental evidence has indicated the benefits of statins for the treatment of postoperative delirium.Previously,clinical trials did not reach definite conclusions on the effects of statins on delirium.Some clinical trials have indicated that statins reduce postoperative delirium and improve outcomes,while some studies have reported negative results.AIM To evaluate whether perioperative rosuvastatin treatment reduces the incidence of delirium and improves clinical outcomes.METHODS This randomized,double-blind,and placebo-controlled trial was conducted in a single center in Jiangsu,China.This study enrolled patients aged greater than 60 years who received general anesthesia during elective operations and provided informed consent.A computer-generated randomization sequence(in a 1:1 ratio)was used to randomly assign patients to receive either rosuvastatin(40 mg/d)or placebo.Participants,care providers,and investigators were all masked to group assignments.The primary endpoint was the incidence of delirium,which was assessed twice daily with the Confusion Assessment Method during the first 7 postoperative days.Analyses were performed on intention-to-treat and safety populations.RESULTS Between January 1,2017 and January 1,2020,3512 patients were assessed.A total of 821 patients were randomly assigned to receive either placebo(n=411)or rosuvastatin(n=410).The incidence of postoperative delirium was significantly lower in the rosuvastatin group[23(5.6%)of 410 patients]than in the placebo group{42(13.5%)of 411 patients[odds ratios(OR)=0.522,95%confidence interval(CI):0.308-0.885;P<0.05]}.No significant difference in 30-d all-cause mortality(6.1%vs 8.7%,OR=0.67,95%CI:0.39-1.2,P=0.147)was observed between the two groups.Rosuvastatin decreased the hospitalization time(13.8±2.5 vs 14.2±2.8,P=0.03)and hospitalization expenses(9.3±2.5 vs 9.8±2.9,P=0.007).No significant differences in abnormal liver enzymes(9.0%vs 7.1%,OR=1.307,95%CI:0.787-2.169,P=0.30)or rhabdomyolysis(0.73%vs 0.24%,OR=3.020,95%CI:0.31-29.2,P=0.37)were observed between the two groups.CONCLUSION The current study suggests that perioperative rosuvastatin treatment reduces the incidence of delirium after an elective operation under general anesthesia.However,the evidence does not reveal that rosuvastatin improves clinical outcomes.The therapy is safe.Further investigation is necessary to fully understand the potential usefulness of rosuvastatin in elderly patients.

Research progress in prevention of postoperative delirium

Postoperative delirium is a common acute confusion state that frequently occurs in patients following surgery.It is characterized by fluctuating consciousness,inattention,disorganized thinking,and altered level of consciousness.Postoperative delirium leads to cognitive decline and dementia,increases the risk of post-operative complications and mortality,and reduces patients’quality of life.Since the pathogenesis of postoperative delirium is unclear and there is no effective treatment,early diagnosis and early intervention are key to preventing and treating postoperative delirium.Currently,the prevention of postoperative delirium is mainly based on non-pharmacological prevention and treatment,whereas some drugs are gradually starting to be used.In the future,efforts are needed to clarify the effect of treatment and to guide the development of a series of more effective and rational delirium treatment strategies adapted to specific national context.

Postoperative Delirium in Elderly Patients May be Associated with Perioperative Blood Pressure Fluctuations

Postoperative delirium(PD)is a common complication of surgery in elderly patients,but its pathophysiological mechanism remains unclear.In order to clarify the role of intraoperative hypotension and fluctuation of blood pressure in the development of PD,we conducted a follow-up study in elderly patients with intraoperative hypotension and fluctuation of blood pressure.A total of 237 patients underwent hip surgery between July 2018 and September 2019,and 158 patients who were eligible for inclusion were enrolled in the study.One day before the operation,the mentality of patients was evaluated by Mini-mental State Examina­tion(MMSE),and the sex,age,height,and weight of the patients were recorded.Radial artery puncture was performed in all patients before anesthesia,intraoperative SBP,MAP and DBP were recorded,and the surgical events of the patients was recorded.The markers associated with PD(TNF-α,IL-6 and S-100β)were determined before and after surgery.Perioperative delirium(PD)was assessed by the prevailing standard of assessment,Confusion of Consciousness Assessment(CAM).Cognitive assessment was evaluated using the Mini-mental State Examination(MMSE).In addition,the timing and type of delirium were recorded.There were 158 patients which were accorded with the inclusion criteria came into the study.The results of our data showed that delirium occurred in 41 patients(25.9%)during the first week after surgery.In the compar­ison between the PD group and the non-PD group,it was found that the patients with postoperative delirium were older,lower body mass index and higher MMSE score before operation.Intraoperative blood pressure is low,usually more than 30%lower than preoperative blood pressure.The levels of TNF-α,IL-6 and Smur100βwere higher after operation.The increased incidence of postoperative delirium may be related to in­traoperative hypotension and intraoperative blood pressure fluctuation.The pathophysiological mechanism may be that hypotension causes low cerebral perfusion,which in turn causes local inflammation in the brain.In addition,postoperative delirium is also more likely to occur in older patients with lower body mass index.

Progress in the treatment of postoperative delirium with chemical medications

Postoperative delirium(POD)is a com-mon postoperative complication that can lead to ad-verse consequences such as prolonged hospitalization,increased medical costs,and higher patient mortality.Chemical medications have demonstrated effectiveness as an intervention in the prevention and treatment of POD,and as a result,have garnered much research attention in recent years.The purpose of this paper is therefore to re-view and evaluate the research on chemical medications for the treatment of POD systematically,to summarize the current findings,and to discuss future directions.

Effects of surgical treatment modalities on postoperative cognitive function and delirium in elderly patients with extremely unstable hip fractures

BACKGROUND As the perioperative risk of elderly patients with extremely unstable hip fractures(EUHFs)is relatively high and therapeutic effect is not satisfactory,new therapeutic strategies need to be proposed urgently to improve the efficacy and clinical outcomes of such patients.AIM To determine the influence of two surgical treatment modalities on postoperative cognitive function(CF)and delirium in elderly patients with EUHFs.METHODS A total of 60 elderly patients consecutively diagnosed with EUHF between September 2020 and January 2022 in the Chongqing University Three Gorges Hospital were included.Of them,30 patients received conventional treatment(control group;general consultation+fracture type-guided internal fixation),and the other 30 received novel treatment(research group;perioperative multidisciplinary treatment diagnosis and treatment+individualized surgical plan+risk prediction).Information on hip function[Harris hip score(HHS)],perioperative risk of orthopedic surgery[Physiological and Operative Severity Score for the Enumeration of Mortality and Morbidity(POSSUM)],CF[Montreal cognitive assessment scale(MoCA)],postoperative delirium[mini-cognitive(Mini-Cog)],adverse events(AEs;internal fixation failure,infection,nonunion,malunion,and postoperative delirium),and clinical indicators[operation time(OT),postoperative hospital length of stay(HLOS),ambulation time,and intraoperative blood loss(IBL)]were collected from both groups for comparative analyses.RESULTS The HHS scores were similar between both groups.The POSSUM score at 6 mo after surgery was significantly lower in the research group compared with the control group,and MoCA and Mini-Cog scores were statistically higher.In addition,the overall postoperative complication rate was significantly lower in the research than in the control group,including reduced OT,postoperative HLOS,ambulation time,and IBL.CONCLUSION The new treatment modality has more clinical advantages over the conventional treatment,such as less IBL,faster functional recovery,more effectively optimized perioperative quality control,improved postoperative CF,mitigated postoperative delirium,and reduced operation-related AEs.

Effects of dexmedetomidine on cardioprotection and other postoperative complications in elderly patients after cardiac and non-cardiac surgerie

BACKGROUND After cardiac and non-cardiac surgeries,elderly patients have a high probability of developing cardiac complications and postoperative delirium.Although several clinical trials have investigated whether perioperative intravenous dexmedetomidine can protect the heart and reduce postoperative complications such as delirium in elderly patients,the obtained results have been inconsistent.We conducted a meta-analysis to investigate the effects of dexmedetomidine on cardioprotection and other postoperative complications in elderly patients undergoing cardiac or non-cardiac surgery.AIM To investigate the effects of dexmedetomidine on cardiac complications and delirium in elderly patients undergoing cardiac or non-cardiac surgery.METHODS The PubMed,Cochrane Library,web of science,and other sources were comprehensively searched for all randomized controlled trials published before May 2021 that investigated the efficacy of dexmedetomidine in the prevention of cardiac and postoperative delirium(POD).RESULTS In total,18 studies involving 1025 patients were included in the meta-analysis.Intravenous dexmedetomidine significantly reduced cardiac troponin I(cTnI)and the inflammatory factor tumor necrosis factor-α(TNF-α)was comparable to the control group.Dexmedetomidine also reduced the POD and mortality rates.However,patients in the dexmedetomidine group were more likely to have a decreased heart rate(within the normal range)and hypotension during dexmedetomidine administration than those in the control group.There was no difference in the occurrence of myocardial infarction,bradycardia,or stroke between the two groups.Dexmedetomidine significantly shortened the time to extubate;however,it did not shorten the length of stay in the intensive care unit.CONCLUSION The administration of dexmedetomidine during cardiac and non-cardiac surgeries can provide myocardial protection by inhibiting inflammation and cTnI,which may be beneficial for the rapid recovery of patients.Meanwhile,the administration of dexmedetomidine reduced the incidence of POD and decreased mortality(in-hospital).

Effects of anesthetic depth on postoperative pain and delirium:a meta-analysis of randomized controlled trials with trial sequential analysis

Background:Whether anesthetic depth affects postoperative outcomes remains controversial.This meta-analysis aimed to evaluate the effects of deepvs.light anesthesia on postoperative pain,cognitive function,recovery from anesthesia,complications,and mortality.Methods:PubMed,EMBASE,and Cochrane CENTRAL databases were searched until January 2022 for randomized controlled trials comparing deep and light anesthesia in adult surgical patients.The co-primary outcomes were postoperative pain and delirium(assessed using the confusion assessment method).We conducted a meta-analysis using a random-effects model.We assessed publication bias using the Begg’s rank correlation test and Egger’s linear regression.We evaluated the evidence using the trial sequential analysis and Grading of Recommendations Assessment,Development and Evaluation(GRADE)methodology.We conducted subgroup analyses for pain scores at different postoperative time points and delirium according to cardiac or non-cardiac surgery.Results:A total of 26 trials with 10,743 patients were included.Deep anesthesia compared with light anesthesia(a mean difference in bispectral index of-12 to-11)was associated with lower pain scores at rest at 0 to 1 h postoperatively(weighted mean difference=-0.72,95%confidence interval[CI]=-1.25 to-0.18,P=0.009;moderate-quality evidence)and an increased incidence of postoperative delirium(24.95%vs.15.92%;risk ratio=1.57,95%CI=1.28-1.91,P<0.0001;high-quality evidence).No publication bias was detected.For the exploratory secondary outcomes,deep anesthesia was associated with prolonged postoperative recovery,without affecting neurocognitive outcomes,major complications,or mortality.In the subgroup analyses,the deep anesthesia group had lower pain scores at rest and on movement during 24 h postoperatively,without statistically significant subgroup differences,and deep anesthesia was associated with an increased incidence of delirium after non-cardiac and cardiac surgeries,without statistically significant subgroup differences.Conclusions:Deep anesthesia reduced early postoperative pain but increased postoperative delirium.The current evidence does not support the use of deep anesthesia in clinical practice.

The role of anesthesia in peri-operative neurocognitive disorders:Molecular mechanisms and preventive strategies

Peri-operative neurocognitive disorders(PNDs)include postoperative delirium(POD)and postoperative cognitive dysfunction(POCD).Children and the elderly are the two populations most vulnerable to the development of POD and POCD,which results in both high morbidity and mortality.There are many factors,including neuroinflammation and oxidative stress,that are associated with POD and POCD.General anesthesia is a major risk factor of PNDs.However,the molecular mechanisms of PNDs are poorly understood.Dexmedetomidine(DEX)is a useful sedative agent with analgesic properties,which significantly improves POCD in elderly patients.In this review,the current understanding of anesthesia in PNDs and the protective effects of DEX are summarized,and the underlying mechanisms are further discussed.