Incidence and Risk Factors for Postoperative Delirium in Patients After Hepatectomy

Prevalence and risk factors of postoperative delirium in tumor patients after free flap reconstruction: A systematic review and meta-analysis of case-control studies

BACKGROUND

Postoperative delirium is a severe complication of flap transplantation surgery, adversely affecting surgical prognoses. The intricate pathophysiology of postoperative delirium renders the elucidation of its risk factors challenging. This research aims to delineate the prevalence and the specific risk factors of postoperative delirium in patients with cancer undergoing free flap reconstruction through a systematic review and meta-analysis to enlighten proactive prevention measures.

METHODS

The researchers systematically queried both the international and Chinese databases. Searches were performed for publications from inception until September 14, 2023, using the terms "free tissue flaps," "delirium," "neoplasms," and "risk factors." Data synthesis and statistical analysis were conducted using Stata SE (version 15.0) to calculate the combined effect size for identified risk factors. Reported outcomes included weighted mean differences or odds ratios with their respective 95% confidence intervals.

RESULTS

Twelve case-control studies were included (ntotal = 3,256). Among them, 515 patients developed postoperative delirium after free flap surgery, compared with 2,741 patients who did not. The outcomes suggest that the risk factors include but are not limited to age, male, late neoplasm staging, use of hypnotic or antipsychotic, history of background diseases, psychiatric review, tracheotomy, and impaired wound healing. In contrast, early neoplasm staging and others are the protective factors with statistical significance. Multivariate analysis further identified significant correlations between preoperative albumin, perioperative blood transfusion, sleep disturbance, postoperative visual analog scale, postoperative albumin, smoking, and the appearance of postoperative delirium.

CONCLUSION

The determined risk factors were grouped into preoperative, intraoperative, and postoperative categories substantiated by current data to present instructions for postoperative delirium prevention.

Predictiveness of preoperative laboratory values for postoperative delirium

Background

Postoperative delirium (POD) is a common postoperative complication, especially in patients over 60 years, with an incidence ranging from 15% to 50%. In most cases, POD manifests in the first 5 days after surgery. Multiple contributing risk factors for POD have been detected. Besides the predisposing factors such as higher age, cognitive impairment, high blood pressure, atrial fibrillation, and past stroke, pathophysiological mechanisms like neuroinflammation are also considered as contributing factors.

Methods

In a subanalysis of the "PRe- Operative  Prediction of postoperative  DElirium by appropriate  SCreening" (PROPDESC) study, the preoperative laboratory values of sodium, potassium, total protein, hemoglobin concentration (Hgb), and white blood cells as well as the biomarkers creatinine, HbA1c, NT-pro-BNP, high sensitive Troponin T (hsTnT), and C-reactive protein (CRP) were assessed to investigate a possible relationship to the occurrence of POD.

Results

After correction for age, physical status classification, surgery risk after Johns Hopkins, and operative discipline (cardiac surgery vs. noncardiac surgery), male patients with a Hgb <13 g/dL had significantly higher odds for POD (p = 0.025). Furthermore, patients with CRP ≥ 10 mg/L, HbA1c value ≥ 8.5% as well as patients with hypernatraemia (>145 mmol/L) presented significantly higher odds to develop POD (p = 0.011, p < 0.001, and p = 0.021, respectively). A raised (>14-52 ng/L) or high (>52 ng/L) hsTnT value was also associated with a significantly higher chance for POD compared to the patient group with hsTnT <14 ng/L (p < 0.001 and p = 0.016, respectively).

Conclusions

Preoperative Hgb, CRP, HbA1c, sodium, and hsTnT could be used to complement and refine the preoperative screening for patients at risk for POD. Further studies should track these correlations to investigate the potential of targeted POD protection and enabling hospital staff to initiate POD-preventing measures in time.

Incidence and risk factors of postoperative delirium following hepatic resection: a retrospective national inpatient sample database study

BACKGROUND

Postoperative delirium (POD) is a common complication after major surgery and can cause a variety of adverse effects. However, no large-scale national database was used to assess the occurrence and factors associated with postoperative delirium (POD) following hepatic resection.

METHODS

Patients who underwent hepatic resection from 2015 to 2019 were screened using the International Classification of Diseases (ICD) 10th edition clinical modification code from the National Inpatient Sample (NIS) Database. Peri-operative factors associated with delirium were screened and underwent statistical analysis to identify independent predictors for delirium following hepatic resection.

RESULTS

A total of 80,070 patients underwent hepatic resection over a five-year period from 2015 to 2019. The overall occurrence of POD after hepatic resection was 1.46% (1039 cases), with a slight upward trend every year. The incidence of elective admission was 6.66% lower (88.60% vs. 81.94%) than that of patients without POD after hepatic resection and 2.34% (45.53% vs. 43.19%) higher than that of patients without POD in teaching hospitals (P < 0.001). In addition, POD patients were 6 years older (67 vs. 61 years) and comprised 9.27% (56.69% vs. 47.42%) more male patients (P < 0.001) compared to the unaffected population. In addition, the occurrence of POD was associated with longer hospitalization duration (13 vs. 5 days; P < 0.001), higher total cost ($1,481,89 vs. $683,90; P < 0.001), and higher in-hospital mortality (12.61% vs. 4.11%; P < 0.001). Multivariate logistic regression identified hepatic resection-independent risk factors for POD, including non-elective hospital admission, teaching hospital, older age, male sex, depression, fluid and electrolyte disorders, coagulopathy, other neurological disorders, psychoses, and weight loss. In addition, the POD after hepatic resection has been associated with sepsis, dementia, urinary retention, gastrointestinal complications, acute renal failure, pneumonia, continuous invasive mechanical ventilation, blood transfusion, respiratory failure, and wound dehiscence / non-healing.

CONCLUSION

Although the occurrence of POD after hepatic resection is relatively low, it is beneficial to investigate factors predisposing to POD to allow optimal care management and improve the outcomes of this patient population.

Risk Factors for Postoperative Delirium in Patients Undergoing Major Head and Neck Cancer Surgery: A Meta-analysis

BACKGROUND

Postoperative delirium (POD) is a common and serious complication after extensive surgery. Understanding the independent and potential modifiable risk factors leading to POD in patients with head and neck cancer (HNC) can provide information for future intervention trials aimed at reducing this risk.

OBJECTIVE

To systematically analyze influencing factors of POD in patients with HNC and identify high-risk individuals for delirium.

METHODS

PubMed, EMBASE, Scopus, OVID, and Cochrane Library were searched for publications prior to June 2023. Comparative studies in which POD risk factors were investigated were identified following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The Newcastle-Ottawa Scale was used to evaluate the study quality. Pooled odds ratios or mean differences for individual risk factors were estimated using the Mantel-Haenszel and inverse-variance methods.

RESULTS

This review included 17 studies with a total of 4188 patients undergoing HNC surgery. The pooled prevalence of POD was 15.44%. Based on pooled analysis, 8 significant risk factors were identified including age older than 70 years, male sex, history of smoking, history of psychiatric disorder, American Society of Anesthesiologists score, albumin level, postoperative insomnia, and fluid intake.

CONCLUSION

In the present study, 8 factors that correlated with POD were identified: 6 preoperative, 1 intraoperative, and 1 postoperative.

IMPLICATIONS FOR PRACTICE

The influencing factors for POD in patients with HNC were identified that can provide a reference for improving the psychological state of the patient population and further development of effective treatment interventions.

Online interpretable dynamic prediction models for postoperative delirium after cardiac surgery under cardiopulmonary bypass developed based on machine learning algorithms: A retrospective cohort study

OBJECTIVE

Postoperative delirium (POD) is strongly associated with poor early and long-term prognosis in cardiac surgery patients with cardiopulmonary bypass (CPB). This study aimed to develop dynamic prediction models for POD after cardiac surgery under CPB using machine learning (ML) algorithms.

METHODS

From July 2021 to June 2022, clinical data were collected from patients undergoing cardiac surgery under CPB at Nanjing First Hospital. A dataset from the same center (October 2022 to November 2022) was also used for temporal external validation. We used ML and deep learning to build models in the training set, optimized parameters in the test set, and finally validated the best model in the validation set. The SHapley Additive exPlanations (SHAP) method was introduced to explain the best models.

RESULTS

Of the 885 patients enrolled, 221 (25.0%) developed POD. 22 (22.0%) of 100 validation cohort patients developed POD. The preoperative and postoperative artificial neural network (ANN) models exhibited optimal performance. The validation results demonstrated satisfactory predictive performance of the ANN model, with area under the receiver operator characteristic curve (AUROC) values of 0.776 and 0.684 for the preoperative and postoperative models, respectively. Based on the ANN algorithm, we constructed dynamic, highly accurate, and interpretable web risk calculators for POD.

CONCLUSIONS

We successfully developed online interpretable dynamic ANN models as clinical decision aids to identify patients at high risk of POD before and after cardiac surgery to facilitate early intervention or care.

Effect of preoperative sleep disorders on delirium in proximal femoral surgery patients aged 60 or older

OBJECTIVE

To examine the effect of preoperative sleep disorders on delirium in patients older than 60 years of age who underwent surgery for proximal femoral fracture.

METHODS

This is a prospective observational study. We prospectively selected 143 patients with proximal femoral fracture who underwent surgery between April 2021 and April 2022. The primary outcome was postoperative delirium (PD). Multiple logistic regression analyses were performed and a receiver operating characteristic (ROC) curve was generated. The preoperative sleep quality of all eligible participants was assessed through the Pittsburgh Sleep Quality Index (PSQI). The Confusion Assessment Method (CAM) was used to assess PD from the first to the seventh day postoperatively. Patients were divided into two groups according to the PD diagnosis: (1) the no PD (NPD) group and (2) the PD (PD) group.

RESULTS

Of 143 eligible patients, 43 (30.1%) were diagnosed with PD. Multiple logistic regression analysis demonstrated that postoperative ICU admissions (OR = 2.801, p = 0.049) and preoperative sleep disorders (OR = 1.477 p < 0.001) were independently associated with PD. A receiver operating characteristic (ROC) curve demonstrated that the preoperative PSQI score was predictive of PD (AUC 0.808, 95% CI 0.724 ~ 0.892, p < 0.001).

CONCLUSION

Preoperative sleeping disorders may be an independent risk factor leading to PD and an independent predictive factor for the development of delirium in proximal femoral surgery patients aged 60 or older.

Effect of laparoscopic liver resection on postoperative delirium in elderly patients with hepatocellular carcinoma

BACKGROUND

Delirium is a multifactorial and heterogeneous syndrome that is defined as acutely altered consciousness. This retrospective multicenter study evaluated the impact of postoperative delirium after liver resection for hepatocellular carcinoma (HCC) in elderly patients.

METHODS

Patients aged ≥75 years, who underwent curative liver resection for HCC at nine university hospitals from April 2010 to December 2017, were evaluated to compare short- and long-term outcomes between patients with and without delirium. Risk factors for delirium were determined using multivariate regression analysis.

RESULTS

The rate of postoperative delirium was 14.2% (n = 80) in the study cohort of 562 patients. Multivariate analysis revealed smoking history, hypertension, sleeping pill consumption, and open liver resection as risk factors for postoperative delirium. The rate of other causes of death was significantly higher in the delirium group than in the no-delirium group although the rate of death at 1 year due to HCC or liver failure was similar between the two groups (p = .015). The 1-year mortality rates due to vascular diseases were 71.4% and 15.4% in the delirium and no-delirium groups, respectively (p = .022). The 1-, 3-, and 5-year survival rates after liver resection were 86.6%, 64.1%, and 36.5% in the delirium group and 91.3%, 71.2%, and 56.9% in the no-delirium group, respectively (p = .046).

CONCLUSION

The multivariate analysis revealed the possible benefits of laparoscopic liver resection in reducing the rate of postoperative delirium after liver resection for HCC in elderly patients.

Effectiveness of nursing intervention to reduce delirium in adult critically ill - A protocol for a randomized trial

The incidence of delirium in intensive care patients remains high, and its consequences have a high negative impact on patients, their families, health care teams, and society in general. Because delirium can lead to increased hospital stay, increased days on mechanical ventilation, increased risk of adverse events, increased memory loss and even increased mortality. However, some factors that precipitate delirium can be modified to reduce its presence and duration through non-pharmacological measures. Thus, the present protocol seeks to establish the theoretical and methodological background to develop and test nursing interventions to reduce delirium in adult patients hospitalized in the intensive care unit. For this reason, it is based on the theoretical elements of delirium and a nursing theory, called the Dynamic Symptoms Model (DSM), to understand the phenomenon and how nursing knowledge can be used to intervene. Thus, a nursing intervention proposal is proposed based on the DSM and scientific evidence, and a methodological design of a randomized controlled clinical trial type with parallel groups, which allows measuring the effectiveness of the designed interventions, following methodological and ethical rigor and with adequate control of biases.

Effect of Remimazolam on Postoperative Delirium in Older Adult Patients Undergoing Orthopedic Surgery: A Prospective Randomized Controlled Clinical Trial

Background

Postoperative delirium is common in older adult patients and associated with a poor prognosis. The use of benzodiazepine was identified as an independent risk factor for delirium, but there is no randomized controlled trial regarding the relationship between remimazolam, a new ultra-short acting benzodiazepine, and postoperative delirium. We designed a randomized controlled trial to evaluate if remimazolam increases the incidence of postoperative delirium compared with propofol in older adult patients undergoing orthopedic surgery with general anesthesia.

Patients and Methods

We enrolled 320 patients aged more than 60 with American Society of Anesthesiologists physical status I-III who underwent orthopedic surgery. Patients were randomized to two groups to receive intraoperative remimazolam or propofol, respectively. Our primary outcome was the incidence of delirium within 3 days after surgery. Secondary outcome was emergence quality including the incidence of emergence agitation, extubation time, and length of post-anesthesia care unit (PACU) stay. Adverse events were also recorded.

Results

The incidence of postoperative delirium was 15.6% in the remimazolam group and 12.4% in the propofol group (Risk ratio, 1.26; 95% CI, 0.72 to 2.21; Risk difference, 3.2%; 95% CI, -4.7% to 11.2%; P = 0.42). No significant differences were observed for time of delirium onset, duration of delirium, and delirium subtype between the two groups. Patients in remimazolam group had a lower incidence of hypotension after induction and consumed less vasoactive drugs intraoperatively, but had a longer postoperative extubation time and PACU stay.

Conclusion

General anesthesia with remimazolam was not associated with an increased incidence of postoperative delirium compared with propofol in older adult patients undergoing orthopedic surgery.

Predisposing and precipitating risk factors for delirium in gastroenterology and hepatology: Subgroup analysis of 718 patients from a hospital-wide prospective cohort study

BACKGROUND AND AIMS

Delirium is the most common acute neuropsychiatric syndrome in hospitalized patients. Higher age and cognitive impairment are known predisposing risk factors in general hospital populations. However, the interrelation with precipitating gastrointestinal (GI) and hepato-pancreato-biliary (HPB) diseases remains to be determined.

PATIENTS AND METHODS

Prospective 1-year hospital-wide cohort study in 29'278 adults, subgroup analysis in 718 patients hospitalized with GI/HPB disease. Delirium based on routine admission screening and a DSM-5 based construct. Regression analyses used to evaluate clinical characteristics of delirious patients.

RESULTS

Delirium was detected in 24.8% (178/718). Age in delirious patients (median 62 years [IQR 21]) was not different to non-delirious (median 60 years [IQR 22]), p = 0.45). Dementia was the strongest predisposing factor for delirium (OR 66.16 [6.31-693.83], p < 0.001). Functional impairment, and at most, immobility increased odds for delirium (OR 7.78 [3.84-15.77], p < 0.001). Patients with delirium had higher in-hospital mortality rates (18%; OR 39.23 [11.85-129.93], p < 0.001). From GI and HPB conditions, cirrhosis predisposed to delirium (OR 2.11 [1.11-4.03], p = 0.023), while acute renal failure (OR 4.45 [1.61-12.26], p = 0.004) and liver disease (OR 2.22 [1.12-4.42], p = 0.023) were precipitators. Total costs were higher in patients with delirium (USD 30003 vs. 10977; p < 0.001).

CONCLUSION

Delirium in GI- and HPB-disease was not associated with higher age per se, but with cognitive and functional impairment. Delirium needs to be considered in younger adults with acute renal failure and/or liver disease. Clinicians should be aware about individual risk profiles, apply preventive and supportive strategies early, which may improve outcomes and lower costs.

High-dose preoperative glucocorticoid for prevention of emergence and postoperative delirium in liver resection: A double-blinded randomized clinical trial substudy

BACKGROUND

Emergence delirium (ED) and postoperative delirium (POD) are associated with increased morbidity and mortality and occur in up to one-third of patients undergoing major non-cardiac surgery, where the underlying pathogenesis is multifactorial, including increased inflammation. We aimed to assess the effect of pre-operative high- versus low-dose glucocorticoid on the occurrence of ED and POD.

METHODS

This was a substudy from a randomized, double-blinded clinical trial. Patients ≥18 years, undergoing open liver resection were randomized 1:1 to high-dose (HD, 10 mg/kg methylprednisolone) or low-dose (LD, 8 mg dexamethasone) glucocorticoid and assessed for ED and POD for a maximum of 4 days during hospitalization. The 3-min Diagnostic Interview for CAM-defined delirium (3D-CAM) was used for assessment, 15 and 90 min after arrival in the post-anesthesia care unit (PACU), and subsequently once daily in the ward.

RESULTS

Fifty-three patients were included in this secondary substudy (26 HD-group and 27 LD-group). ED occurred in n = 5 HD versus n = 6 LD patients 15 min after PACU arrival. At 90 min after PACU arrival, 4 patients had ED, all from LD-group, and resulted in significantly longer PACU admission, 273 versus 178 min in ED versus Non-ED patients. During the first 4 days in the ward, n = 5 patients had at least one occurrence of POD, all from LD-group.

CONCLUSIONS

The primary finding of the current substudy was a lower occurrence of ED/POD in the PACU 90 min after arrival and during the first four postoperative days in patients receiving high-dose glucocorticoid compared with patients receiving low-dose glucocorticoid. The two study groups were not evenly balanced concerning known explanatory factors, i.e., age and size of surgery, which calls for larger studies to elucidate the matter.

Impact of combined epidural anaesthesia/analgesia on postoperative cognitive impairment in patients receiving general anaesthesia: a meta-analysis of randomised controlled studies

BACKGROUND

To investigate the efficacy of combined epidural anaesthesia/analgesia (EAA) against postoperative delirium/cognitive dysfunction (POD/POCD) in adults after major non-cardiac surgery under general anaesthesia (GA).

METHODS

The databases of PubMed, Google scholar, Embase and Cochrane Central Register were searched from inception to November 2021 for available randomised controlled trials (RCTs) that assessed the impact of EAA on risk of POD/POCD. The primary outcome was risk of POD/POCD, while the secondary outcomes comprised postoperative pain score, length of hospital stay (LOS), risk of complications, and postoperative nausea/vomiting (PONV).

RESULTS

Meta-analysis of eight studies with a total of 2376 patients (EAA group: 1189 patients; non-EAA group: 1187 patients) revealed no difference in risk of POD/POCD between the EAA and the non-EAA groups [Risk ratio (RR): 0.68; 95% CI: 0.41 to 1.13, p = 0.14, I² = 73%], but the certainty of evidence was very low. Nevertheless, the EAA group had lower pain score at postoperative 24 h [mean difference (MD): -1.49, 95% CI: -2.38 to -0.61; I² = 98%; five RCTs; n = 476] and risk of PONV (RR = 0.73, 95% CI: 0.57 to 0.93, p = 0.01, I² = 0%; three RCTs, 1876 patients) than those in the non-EAA group. Our results showed no significant impact of EAA on the pain score at postoperative 36-72 h, LOS, and risk of complications.

CONCLUSION

This meta-analysis demonstrated that EAA had no significant impact on the incidence of POD/POCD in patients following non-cardiac surgery.

Risk factors and prevention for postoperative delirium after orthopedic surgery

BACKGROUND

Postoperative delirium significantly delays the recovery of patients. This study sought to explore the risk factors and to prevent postoperative delirium after orthopedic surgery.

MATERIALS AND METHODS

In the part of retrospective study, 456 cases over 70-year-old that underwent one of three types of orthopedic surgery were included and were defined as the retrospective group. The risk factors of postoperative delirium were analyzed by logistic regression. In the part of prospective study, 86 cases of the same age and the same surgery were included and were defined as the prospective group. Positive interventions were used by shortening the fasting time and increasing the perioperative rehydration. The differences of postoperative delirium incidence between the retrospective group and the prospective group were analyzed.

RESULTS

Compared with patients with normal postoperative electrolytes, postoperative creatinine <68.20 μmol/L, and fluid infusion during fasting >119.66 mL/h, postoperative electrolyte disorders (odds ratio [OR]: 2.864; 95% confidence interval [CI]: 1.374, 5.970), postoperative creatinine ≥68.20 μmol/L (OR: 2.660; 95% CI: 1.328, 5.328), and fluid infusion during fasting ≤119.66 mL/h (OR: 2.372; 95% CI: 1.197, 4.704) were the risk factors for postoperative delirium. After positive intervention, the postoperative delirium incidence of the prospective group was 5.8% (5/86), and it was lower than 18.4% (84/456) of the retrospective group (P < 0.05).

CONCLUSIONS

Elevated postoperative creatinine, postoperative electrolyte disorders, and lower fluid infusion during fasting were three risk factors for postoperative delirium. By shortening the fasting time and increasing the perioperative rehydration, the incidence of postoperative delirium could be reduced.

The assessment of risk factors for postoperative delirium using cubic spline curves in gastroenterological surgery

PURPOSE

Delirium is associated with longer hospital stays and increased medical costs and mortality. This study explored the risk factors for postoperative delirium in gastroenterological surgery and investigated the association between qualitative changes in risk factors and the incidence of postoperative delirium.

METHODS

A total of 418 patients > 18 years old who underwent gastroenterological surgery at our department between April 2018 and September 2019 were included. Risk factors were identified by comparing patients with and without postoperative delirium. Continuous variables were evaluated graphically using cubic spline curves. A logistic regression analysis was performed to assess independent risk factors.

RESULTS

The incidence of postoperative delirium was 6.9%. The cubic spline curve showed that the incidence of postoperative delirium began to increase at 50 years old and increased sharply at 70 years old. A multiple logistic regression analysis of patients > 50 years old identified 5 risk factors: age ≥ 70 years, preoperative serum albumin ≤ 3.8 g/dL, psychosis, sedative-hypnotics, and intensive-care unit admission.

CONCLUSION

The risk of postoperative delirium increases progressively at 50 years old and sharply at 70 years old. Advanced age, preoperative hypoalbuminemia, psychosis, sedative-hypnotics, and intensive-care unit admission are risk factors for postoperative delirium in patients > 50 years old undergoing gastroenterological surgery.

Development and validation of a risk score for predicting postoperative delirium after major abdominal surgery by incorporating preoperative risk factors and surgical Apgar score

STUDY OBJECTIVE

To develop and validate a simple delirium-predicting scoring system in patients undergoing major abdominal surgery by incorporating preoperative risk factors and intraoperative surgical Apgar score (SAS).

DESIGN

Observational retrospective cohort study.

SETTING

A tertiary general hospital in China.

PATIENTS

1055 patients who received major abdominal surgery from January 2015 to December 2019.

MEASUREMENTS

We collected data on preoperative and intraoperative variables, and postoperative delirium. A risk scoring system for postoperative delirium in patients after major open abdominal surgery was developed and validated based on traditional logistic regression model. The elastic net algorithm was further developed and evaluated.

MAIN RESULTS

The incidence of postoperative delirium was 17.8% (188/1055) in these patients. They were randomly divided into the development (n = 713) and validation (n = 342) cohorts. Both the logistic regression model and the elastic net regression model identified that advanced age, arrythmia, hypoalbuminemia, coagulation dysfunction, mental illness or cognitive impairments and low surgical Apgar score are related with increased risk of postoperative delirium. The elastic net algorithm has an area under the receiver operating characteristic curve (AUROC) of 0.842 and 0.822 in the development and validation cohorts, respectively. A prognostic score was calculated using the following formula: Prognostic score = Age classification (0 to 3 points) + arrythmia + 2 * hypoalbuminemia + 2 * coagulation dysfunction + 4 * mental illness or cognitive impairments + (10-surgical Apgar score). The 22-point risk scoring system had good discrimination and calibration with an AUROC of 0.823 and 0.834, and a non-significant Hosmer-Lemeshow test P = 0.317 and P = 0.853 in the development and validation cohorts, respectively. The bootstrapping internal verification method (R = 1000) yielded a C-index of 0.822 (95% CI: 0.759-0.857).

CONCLUSION

The prognostic scoring system, which used both preoperative risk factors and surgical Apgar score, serves as a good first step toward a clinically useful predictive model for postoperative delirium in patients undergoing major open abdominal surgery.

Analysis of Delirium From the Dynamic Symptoms Model: A Literature Review

Delirium is a manifestation of brain injury or acute and generalized dysfunction of the upper cerebral cortical processes. In this way, it is important to analyze delirium more broadly as a symptom to understand and intervene taking into account that it is manifesting the presence of brain lesions whose consequences are deleterious to the neurological performance of patients. This article is intended to present a comprehensive approach of delirium analyzed from a symptom perspective and from theoretical and conceptual structure, such as the Dynamic Symptoms Model, specific to the nursing practice. A literature review related to delirium and components of Dynamic Symptoms Model was carried out. We searched the MEDLINE, ScienceDirect, SciELO, and Scopus databases using the terms Delirium, Intensive Care Units, Nursing, and Risk Factor. The existing literature provides evidence of the antecedents, experience, interventions, interactions, and consequences of delirium, which are components of the Model. Thus, the analysis from the Dynamic Symptoms Model perspective bears relevance and contributes to the understanding and approach of delirium.

Preventative effects of ramelteon against postoperative delirium after elective liver resection

Background

Postoperative delirium was reported to be associated with increased postoperative mortality after liver resection. Therefore, it is crucial to prevent postoperative delirium in such cases. Ramelteon, an agonist of melatonin receptor has been suggested to be useful for preventing delirium. The aim of this study was to examine whether ramelteon is effective at preventing delirium after elective liver resection.

Methods

The cases of patients who underwent liver resection at Nara Medical University (Nara, Japan) between January 2014 and August 2018 were analyzed. During the period from January 2017 to August 2018, ramelteon was prospectively administered to patients who underwent liver resection [8 mg/day on the day before surgery and on postoperative days 1 to 3] (ramelteon group), whereas ramelteon was not administered during the period from January 2014 to December 2016 (control group). The perioperative outcomes of the two groups were compared.

Results

There were 120 patients in the ramelteon group and 186 patients in the control group. No significant intergroup differences in background factors, including age, gender, and preoperative serological laboratory data, were detected. The incidence of postoperative delirium was significantly lower in the ramelteon group (5.8% vs. 15.1%, P = 0.035). Multivariate analysis revealed that being aged ≥75 (P = 0.002), being male (P = 0.020), cardiovascular disease (P = 0.023), blood loss ≥1000ml (P = 0.001) and the absence of ramelteon treatment (P = 0.046) were independent risk factors for postoperative delirium.

Conclusion

The administration of ramelteon might reduce the risk of postoperative delirium after elective liver resection.

Predictive Factors of Postoperative Delirium in Patients After Pancreaticoduodenectomy

BACKGROUND

Postoperative delirium is a common serious complication after various types of surgery. However, the incidence and predictive factors associated with delirium after pancreaticoduodenectomy (PD) have not been investigated. Thus, this study aimed to investigate the incidence and predictive factors of postoperative delirium in patients who underwent PD.

METHODS

This study included 155 consecutive patients who underwent PD. Patients with and without postoperative delirium were compared to identify differential patient characteristics. Multivariate regression analysis was used to statistically identify independent predictive factors significantly associated with the development of postoperative delirium.

RESULTS

Postoperative delirium developed in 27 (22.4%) of 155 patients. The majority of incidents occurred on postoperative day 2, and the mean delirium duration was 4.6 ± 4.8 days. Patients with postoperative delirium had an older age and a previous history of benzodiazepine use. A multivariate analysis revealed that the development of delirium was significantly correlated with these two factors. Receiver-operator characteristics (ROC) curve analysis of the two factors yielded an area under the ROC curve of 0.823 (0.750-0.896), suggesting good discrimination power.

CONCLUSIONS

This study reports on the incidence of postoperative delirium after PD. Furthermore, we identified age and use of benzodiazepines as significant predictive factors for developing delirium after PD. These results contribute to the prediction and treatment of postoperative delirium.

Postoperative Serum Albumin Decrease Independently Predicts Delirium in the Elderly Subjects after Total Joint Arthroplasty

Background:

Postoperative delirium (POD), a neurobehavioral syndrome induced by dysfunction of neural activity, is a common and serious complication. This current study aimed to investigate independent predictors for POD in elderly subjects after total joint arthroplasty (TJA).

Methods:

Eligible elderly patients (≥65 years) who underwent elective unilateral primary hip or knee arthroplasty under epidural anesthesia from October 2016 to January 2019 were consecutively enrolled. POD was diagnosed following the guidance of the 5th edition of Diagnostic and Statistical Manual of Mental Disorders, (DSM V, 2013). The relative change in serum Alb (ΔAlb) was defined as the absolute value of (preoperative Alb value– nadir value within postoperative day 2)/preoperative Alb ×100%. The predictive value of ΔAlb for POD was evaluated by receiver operating characteristic (ROC) curve analysis. Univariate and multivariate logistic regression analyses were used for evaluating risk factors for POD.

Results:

A total of 328 patients were enrolled in the analysis, of which 68 (20.7%, 68/328) patients developed POD within postoperative 7 days. ΔAlb was an effective predictor for POD with an area under the curve (AUC) of 0.821, a sensitivity of 76.15% and a specificity of 70.59%, respectively (P<0.001). Univariate and multivariate logistic regression analyses indicated that ΔAlb was the only independent risk factor for POD (OR: 2.43, 95%CI: 1.17–4.86, P=0.015).

Conclusions:

ΔAlb was an independent risk factor for POD in elderly subjects after TJA.

Postoperative delirium after lung resection for primary lung cancer: Risk factors, risk scoring system, and prognosis

Delirium is a common post-surgical complication, but few studies have examined postoperative delirium following lung cancer surgery. The purpose of this study was to clarify the risk factors of postoperative delirium, to construct a useful scoring system, and to clarify the relationship between delirium and prognosis after lung cancer surgery. We retrospectively analyzed data from 570 patients who underwent surgery for primary lung cancer. Logistic regression analysis was used to determine the effects of various factors on the onset of delirium. Kaplan–Meier analysis was performed to determine the relationship between delirium and prognosis. Postoperative delirium occurred in 6.7% of the patients. Three risk factors were identified, and the risk scores were determined as follows: 2×(cerebrovascular disease history) + 1×(squamous cell carcinoma) + 1×(age older than 75 years). Scores 0–1 denoted low risk, 2 denoted intermediate risk, and 3–4 denoted high risk. Additionally, we found that patients who developed delirium had significantly shorter overall survival. However, there was no difference in the frequency between cancer-related death and non-cancer related death when comparing the delirium and non-delirium groups. We identified the risk factors, i.e., cerebrovascular disease history, squamous cell carcinoma, and age older than 75 years, that determine the onset of delirium after lung cancer surgery and constructed a useful scoring system. In addition, although the prognosis of the delirium group was poor, the factor that determines prognosis may not be cancer per se but vulnerability in the patient background.

Effective prediction of postoperative complications for patients after open hepatectomy: a simplified scoring system based on perioperative parameters

BACKGROUND

The aim of the study was to develop a scoring system for the prediction of postoperative complications of open hepatectomy.

METHOD

All consecutive patients receiving open hepatectomy from 2015 to 2017 were included in the study. Univariate and multivariate analyses were used to confirm the risk factors for postoperative complications. Afterwards, a novel scoring system was developed to predict the postoperative complications.

RESULTS

The study included a total of 207 patients. For the test dataset, multivariate analysis indicated that diabetes, scale of surgery, serum potassium, and blood loss versus body weight were independent risk factors of the postoperative complications. The area under the curve (AUC) of the novel scoring system we proposed for prediction of postoperative complications of hepatectomy was 0.803, which is comparable with the AUCs of previous scoring systems. Furthermore, in the validation dataset, the corresponding AUC of the new scoring system was 0.717.

CONCLUSION

This novel and simplified scoring system can effectively predict the postoperative complications of open hepatectomy and could help identify patients who are at high risk of postoperative complications.

Does an extreme age (≥80 years) affect outcomes in patients after liver cancer surgery? A meta-analysis

BACKGROUND

Increasing global life expectancy has resulted in a greater demand for cancer surgery in aged patients. However, whether extreme age causes poorer clinical outcomes remains unclear. This meta-analysis aimed to evaluate the impact of extreme age (≥80 years) on outcomes in patients after liver cancer surgery.

METHODS

A systematic search was performed to enrol relevant studies. Data were analysed using fixed-effects or random-effects models. Eight retrospective studies involving 253 participants older than 80 years were included.

RESULTS

Compared with younger patients, patients of extreme age (≥80 years) who had undergone curative liver cancer surgery experienced less operating time and blood loss (both P < 0.0001); a larger size (weighted mean difference = 0.48 cm, 95% confidence interval (CI) 0.08-0.87 cm; P = 0.02) and more advanced stage of hepatocellular carcinoma (risk ratio (RR) = 1.20, 95% CI 1.04-1.39; P = 0.01); a higher overall morbidity (RR = 1.24, 95% CI 1.05-1.47; P = 0.01); and more post-operative ileus (POI) (RR = 3.45, 95% CI 1.03-11.56; P = 0.04), delirium (RR = 3.04, 95% CI 1.36-6.78; P = 0.007) and cardiovascular events (RR = 6.17, 95% CI 2.79-13.60; P < 0.00001). No significant difference was noted in overall (hazard ratio (HR) = 1.15, 95% CI 0.87-1.53; P = 0.32) or disease-free (HR = 0.96, 95% CI 0.75-1.24; P = 0.77) survival.

CONCLUSION

Although an extreme age may not be a contraindication for undertaking liver cancer surgery, it may cause more morbidity. Perioperative intervention should be considered for prevention and early treatment of POI, delirium and cardiovascular events.

Risk factors for postoperative delirium in patients undergoing free flap reconstruction for oral cancer

The aim of this study was to investigate risk factors for postoperative delirium in patients undergoing free flap reconstruction for defects after oral cancer resection. This was a non-randomized, retrospective cohort study involving 102 patients who underwent oral cancer resection and free flap reconstruction. Data were collected from the medical records. Postoperative delirium occurred in 34 patients (33.3%), of whom 27 were male and seven were female. High preoperative total protein and albumin, diabetes mellitus, history of smoking, use of hypnotics or antipsychotics, time until getting out of bed after surgery, and postoperative insomnia were significantly related to delirium in the univariate analysis (P<0.05). In a multiple logistic regression model, high preoperative albumin (odds ratio 4.45), postoperative insomnia (odds ratio 10.72), and history of smoking (odds ratio 2.91) were significant risk factors for delirium (P<0.05). The analysis of laboratory data before and after surgery showed greater decreases in albumin, total protein, and haemoglobin after surgery in patients with postoperative delirium than in those without this condition. These results show that the perioperative maintenance of nutritional status and early postoperative management of the sleep cycle are important to prevent delirium after oral cancer resection and free flap reconstruction.

Risk Factors of Delirium in Sequential Sedation Patients in Intensive Care Units

Background

Delirium is a primary adverse event in ventilated patients who receive long-term monosedative treatment. Sequential sedation may reduce these adverse effects. This study evaluated risk factors for delirium in sequential sedation patients.

Methods

A total of 141 patients who underwent sequential sedation were enrolled. Delirium was diagnosed using Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) scale. Univariate and multivariate Cox proportional hazards regressions were used to predict risk factors.

Results

Older age (≥51) (RR = 2.432, 95% CL 1.316–4.494, p = 0.005), higher SOFA score (≥14) (RR = 2.022, 95% CL 1.076–3.798, p = 0.029), regular smoking (RR = 2.366, 95% CL 1.277–4.382, p = 0.006), and higher maintenance dose of midazolam (RR = 1.052, 95% CL 1.000–1.107, p = 0.049) and fentanyl (RR = 1.045, 95% CL 1.019–1.072, p = 0.001) when patients met sequential criteria, were independent risk factors of delirium. Sequential sedation with dexmedetomidine (RR = 0.448, 95% CL 0.209–0.963, p = 0.040) was associated with a lower risk of delirium.

Conclusions

Older age, higher SOFA score, regular smoking, and higher maintenance dose of midazolam and fentanyl when patients met sequential criteria were independent risk factors of delirium in sequential sedation patients. Sequential sedation with dexmedetomidine reduced risk of delirium.