Higher Incidence Of Postoperative Delirium Research Articles

Association between intraoperative electroencephalogram burst suppression and postoperative delirium: A systematic review and meta-analysis.

Electroencephalogram burst suppression can be associated with postoperative delirium; however, the results of relevant studies are discrepant. This systematic review and meta-analysis aimed to assess the association between intraoperative burst suppression and postoperative delirium in adult surgical patients. PubMed, MEDLINE, Embase, Google Scholar, and the Cochrane Central Register of Controlled Trials were systematically searched and updated in May 2023. We included cohort studies, case-control studies, and randomized-controlled studies reporting on postoperative delirium incidence with documented intraoperative burst suppression in adults receiving general anesthesia for any surgery. The primary outcome was the pooled odds ratio (OR) for postoperative delirium in cases with intraoperative burst suppression compared to those without burst suppression, calculated using a random-effects model. Two independent investigators extracted the data. The protocol was prospectively registered in PROSPERO (registration number: CRD42022326479); the results were reported according to PRISMA guidelines. Fourteen studies (6435 patients) were included in the analysis. The overall incidence of postoperative delirium was 21.1% (1358/6435). Patients with intraoperative burst suppression had a higher incidence of postoperative delirium than those without burst suppression (pooled OR, 1.492; 95% confidence interval (CI) [1.022-2.178]; I2 =44%; 95% CI [0%-75%]; τ2 = 0.110). The intraoperative duration of burst suppression was significantly longer in patients who developed postoperative delirium (standardized mean difference [SMD] 0.462 [95% CI, 0.293-0.632]; I2 = 63%; 95% CI [16%-84%]; τ2 = 0.027). The burst suppression ratio was significantly higher in the delirium group (SMD 0.150; 95% CI [0.055-0.245]; I2 = 0%; 95% CI [0%-85%]; τ2 = 0.00). Our meta-analysis suggests an association between intraoperative burst suppression and postoperative delirium; however, the quality of evidence was very low. The limited number of studies and substantial heterogeneity across them emphasize the need for further high-quality studies to establish a more robust conclusion.

Sex-based disparities in ascending aortic aneurysm surgery outcomes: a comprehensive analysis of 1148 consecutive patients with propensity-score matching

BackgroundWomen undergoing cardiac surgery have been historically recognized to carry higher periprocedural mortality risk. We aimed to investigate the influence of sex on clinical presentation, perioperative, and long-term outcomes in patients who undergo surgery for ascending aortic aneurysm.MethodsWe conducted a retrospective review of 1148 consecutive patients (380 [33.1%] female) who underwent thoracic aortic surgery under moderate hypothermic circulatory arrest for ascending aortic aneurysms between 2001 and 2021. Baseline and operative characteristics, in-hospital mortality, and survival were compared between male and female patients before and after propensity-score-matched (PSM) analysis.ResultsWomen were significantly older (median age: 69 [IQR: 63–75] vs. 67 [IQR: 58–73]; P < 0.001), while men had a higher prevalence of aortic valve stenosis, bicuspid valve and coronary artery disease at the time of surgery (P < 0.05). After PSM, EuroSCORE II (4.36 [2.68; 6.87] vs. 3.22 [1.85; 5.31]; p < 0.001), and indexed aortic diameter were significantly higher in female patients (2.94 [2.68; 3.30] vs. 2.58 [2.38; 2.81] cm/m2, p < 0.001). In the matched cohort, men were more likely to experience postoperative delirium (18.1% vs. 11.5%; P = 0.002), and postoperative neurological deficits (6.7% vs. 3.0%, P = 0.044),. Female patients were more likely to receive postoperative packed red blood cells (p = 0.036) and fresh frozen plasma (p = 0.049). In-hospital and 30-day mortality was similar between both groups. Long-term survival was comparable between both groups with 88% vs. 88% at 5 years, 76% vs. 71% at 10 years, and 59% vs. 47% at 15 years.ConclusionFemale patients required more transfusions, while males had a higher incidence of postoperative delirium and neurological deficits. Differences in preoperative age and timing of surgery between the sexes could be attributed to variations in comorbidity profiles and the greater prevalence of concomitant surgery indications in males.

Increased Risk of Postoperative Complications in Patients Who Have Obstructive Sleep Apnea Undergoing Total Joint Arthroplasty: A Systematic Review and Meta-Analysis

BackgroundObstructive sleep apnea (OSA) has been linked to multiple adverse health outcomes and postoperative complications. Despite the high prevalence of OSA in patients undergoing total joint arthroplasty (TJA), few studies have evaluated the postoperative course of OSA patients after joint arthroplasty surgery. MethodsPubMed (MEDLINE) and Scopus (EMBASE, MEDLINE, and COMPENDEX) were used to conduct a systematic review of articles from inception to July 2023. Primary studies comparing postoperative outcomes following TJA between patients who had and did not have OSA were included. Postoperative medical complications, utilization of critical care, hospital stay, and mortality data were extracted. Descriptive statistics and random-effects meta-analysis models were used to analyze the available data. Included studies were evaluated for methodological risks of bias using the risk of bias in non-randomized studies of interventions. This review was registered on the International Prospective Register of Systematic Reviews (ID: CRD42023447610). ResultsThere were 7 studies with a total of 20,977 patients (9,425 hip; 11,137 knee; 415 hip or knee) that were included. Pulmonary complications were most frequently studied, followed by thromboembolic events. Cardiac, gastrointestinal, hematologic, genitourinary, and delirium events were also reported across studies. Meta-analysis revealed that OSA patients had 4-fold increased odds of overall medical complications (OR [odds ratio], 4.23; 95% confidence interval (CI), 2.97 to 6.04; P < .001; I2 = 0%), 4-fold increased odds of pulmonary complications (OR, 4.31; 95% CI, 2.82 to 6.60; P < .001; I2 = 0%), 2-fold increased odds of thromboembolic complications (OR, 1.92; 95% CI, 1.22 to 3.03; P = .005; I2 = 9%), and 4-fold increased odds of delirium (OR, 3.94; 95% CI, 1.72 to 9.04; P = .001; I2 = 0%). ConclusionsA significant association was found between OSA and overall medical, pulmonary, and thromboembolic complications. These patients also had a higher incidence of postoperative delirium. The present findings underscore the need for comprehensive perioperative strategies to mitigate these risks in OSA patients who elect to undergo TJA.

Prognostic Nutritional Index and the Risk of Postoperative Complications After Spine Surgery: A Meta-Analysis

BackgroundA low prognostic nutritional index (PNI) may reflect malnutrition, which has been associated with poor prognosis in patients with various clinical conditions. The aim of the systematic review and meta-analysis was to investigate the association between preoperative PNI and risk of postoperative complications in adult patients after spine surgery. MethodsAn extensive search was conducted on PubMed, Embase, and Web of Science to identify relevant cohort studies. Random-effects models were employed to combine the findings, taking into account the potential influence of heterogeneity. ResultsTen cohort studies involving 3249 patients receiving spine surgeries were included. Pooled results showed that a low preoperative PNI was associated with an increased risk of overall postoperative complications in these patients (odds ratio [OR]: 1.82, 95% confidence interval [CI]: 1.42 to 2.34, p < 0.001; I2 = 49%). Specifically, a preoperative malnutrition as evidenced by a low PNI was associated with a higher incidence of postoperative delirium (OR: 2.36, 95% CI: 1.52 to 3.66, p < 0.001; I2 = 38%) and surgical site infection (OR: 1.41, 95% CI: 1.15 to 1.73, p = 0.001; I2 = 0%). Sensitivity analyses by excluding one study at a time did not significantly change the results (p all < 0.05). ConclusionA preoperative low PNI may be a risk factor of increased incidence of overall postoperative complications, postoperative delirium, and surgical site infection in adult patients after spine surgeries.

Post-operative delirium in different age groups and subtypes: a systematic review of case reports.

To explore the clinical presentations and outcomes among different ages and subtypes of post-operative delirium patients. Systematic review of Published Cases. We comprehensively searched PubMed, EMBASE, and MEDLINE for published case reports of post-operative delirium up to April 2023. The systematic review has been registered with PROSPERO. Two researchers independently conducted unblinded reviews of the full-text articles. This study included 116 patients with post-operative delirium. Compared to post-operative delirium patients aged 65 and above, those between 18 and 65 years old have lower rates of a history of hypertension, cardiovascular disease and urinary system disorder comorbidities, as well as higher usage rates of fentanyl analogs and lorazepam. Additionally, these patients exhibit lower incidences of anemia and renal failure, along with a lower mortality rate. Compared to post-operative delirium patients aged 65 and above, those under 18 years old have a higher rate of fentanyl analog usage and a higher incidence of post-operative delirium following neurological surgeries. Among the hypoactive, hyperactive, and mixed subtypes, the reasons for surgery, such as cardiovascular diseases, reproductive system diseases, and neurological disorders, significantly varied among these three subtypes. Furthermore, substance abuse history and medication usage patterns also significantly varied among these three subtypes. Our investigation has revealed noteworthy insights into post-operative delirium in different patient populations. Notably, age emerged as a pivotal factor. Compared to elderly patients (≥65 years), those aged 18 to 65 demonstrate better prognosis. Additionally, patients younger than 18 years with post-operative delirium have a higher incidence of delirium following neurosurgical procedures compared to those elderly patients. Additionally, a strong association was found between a history of substance abuse and hyperactive delirium. Variations in drug use patterns were observed across different subtypes. Importantly, post-operative delirium patients younger than 18 years, as well as those aged 18 to 65 with mixed-subtype delirium, exhibited similar high mortality rates as elderly patients. This underscores the need for increased attention to post-operative delirium patients under 65 and highlights the necessity of rapid identification and early intervention for these populations at risk of poor outcomes. https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023473383, Identifier [Registration ID: CRD 42023473383].

The Effect of ACE Inhibitors/ARBs Withdrawal on the Risk of Postoperative Complications in Abdominal Surgery

A significant proportion of patients undergoing non-cardiac surgery receive therapy with angiotensin converting enzyme (ACE) inhibitors/angiotensin II receptor blockers (ARBs), which are usually prescribed for treatment of arterial hypertension and CHF. Current guidelines fail to provide clear consensus on whether it is worth discontinuing ACEi/ARBs before non-cardiac surgery. The aim of this research was to assess the contribution of pre-op ACEi/ARBs withdrawal to the development of postoperative complications in patients after abdominal surgery using data from STOPRISK database.Materials and methods. Data of 1945 patients from of the STOPRISK database was used for the analysis. Patients were retrospectively divided into two groups: first group (N=471, 24.2%) included patients subjected to ACEi/ARBs withdrawal 24 hours before surgery, second group (N=1474, 75.8%) included patients continuing on ACEi/ARBs therapy. The 30-day outcomes were analyzed — postoperative complications (acute kidney injury, acute respiratory distress syndrome, anastomosis failure, arrhythmias, circulatory arrest, cardiogenic pulmonary edema, postoperative delirium, myocardial infarction, pneumonia, ileus, postoperative bleeding, pulmonary embolism, acute cerebrovascular accident, wound infection) and mortality. We were not evaluating intraoperative and postoperative arterial hypotension and hypertension, we analyzed the use of vasopressors as a surrogate marker. ACEi/ARBs re-initiation after surgery was not evaluated.Results. One or more post-operative complications were documented in 113 patients (5.8%). Only postoperative delirium was more common in patients (1.06% vs. 0.27%, P=0.027) after ACEi/ARBs withdrawal 24 hours before surgery, the difference reached statistical significance. Sub-analysis in the group of patients with arterial hypertension as the only comorbidity showed no statistically significant differences in the outcomes. Sub-analysis in the group of patients with CFH showed higher incidence of postoperative delirium after ACEi/ARBs withdrawal (2.68% vs. 0.6%, P=0.023). The logistic regression analysis showed that the risk of developing postoperative delirium is influenced by age, vasopressor support, and ACEi/ARBs withdrawal (the area under the curve for the model was 0.92 (0.90–0.93).Conclusion. Rates of pre-op ACEi/ARBs withdrawal (24.2%) are consistent with published data. In the entire cohort, ACEi/ARBs withdrawal resulted in higher incidence of postoperative delirium, as well as in the subgroup of patients with CHF, while ACEi/ARBs withdrawal in the subgroup of patients with arterial hypertension had no influence on postop complications.ACEi/ARBs withdrawal, along with hemodynamic instability and older age, contributes to the development of postoperative delirium, which is the subject of future research.

Intra-operative electroencephalogram frontal alpha-band spectral analysis and postoperative delirium in cardiac surgery: A prospective cohort study.

Postoperative delirium (POD) remains a frequent complication after cardiac surgery, with pre-operative cognitive status being one of the main predisposing factors. However, performing complete pre-operative neuropsychological testing is challenging. The magnitude of frontal electroencephalographic (EEG) α oscillations during general anaesthesia has been related to pre-operative cognition and could constitute a functional marker for brain vulnerability. We hypothesised that features of intra-operative α-band activity could predict the occurrence of POD. Single-centre prospective observational study. University hospital, from 15 May 2019 to 15 December 2021. Adult patients undergoing elective cardiac surgery. Pre-operative cognitive status was assessed by neuropsychological tests and scored as a global z score. A 5-min EEG recording was obtained 30 min after induction of anaesthesia. Anaesthesia was maintained with sevoflurane. Power and peak frequency in the α-band were extracted from the frequency spectra. POD was assessed using the Confusion Assessment Method for Intensive Care Unit, the Confusion Assessment Method and a chart review. Sixty-five (29.5%) of 220 patients developed POD. Delirious patients were significantly older with median [IQR] ages of 74 [64 to 79] years vs. 67 [59 to 74] years; P < 0.001) and had lower pre-operative cognitive z scores (-0.52 ± 1.14 vs. 0.21 ± 0.84; P < 0.001). Mean α power (-14.03 ± 4.61 dB vs. -11.59 ± 3.37 dB; P < 0.001) and maximum α power (-11.36 ± 5.28 dB vs. -8.85 ± 3.90 dB; P < 0.001) were significantly lower in delirious patients. Intra-operative mean α power was significantly associated with the probability of developing POD (adjusted odds ratio, 0.88; 95% confidence interval (CI), 0.81 to 0.96; P = 0.007), independently of age and only whenever cognitive status was not considered. A lower intra-operative frontal α-band power is associated with a higher incidence of POD after cardiac surgery. Intra-operative measures of α power could constitute a means of identifying patients at risk of this complication. NCT03706989.

Visual Dysfunction is a Risk Factor of Postoperation Delirium in Parkinson Disease

To investigate the incidence of and factors influencing postoperative delirium (POD) in Parkinson's disease after deep brain stimulation (DBS) surgery. A total of 272 patients with Parkinson's disease who underwent DBS completed the Visual Impairment in Parkinson's Disease Questionnaire (VIPD-Q) and underwent neuro-ophthalmologic examinations including optical coherence tomography and fundus vessel analysis. We retrospect the prevalence of POD in groups with different VIPD-Q scores, retinal nerve fiber layer (RNFL) thicknesses, and vessel percentage areas (VPA). A predictive model based on the VIPD-Q was constructed using multivariate logistic regression and verified using bootstrap validation. POD was experienced by 65 (23.9 %) of 272 patients. Patients with PD who had visual impairment (VIPD-Q > 6) had a higher incidence of POD (chi-square, p <0.001). The thickness of the retinal nerve fiber layer and vessel percentage area were also correlated with POD risk. Differences in implantation locations (subthalamic nucleus or pars interna of globus pallidus), operation times, and general anesthesia times did not affect the prevalence of DBS-related POD. A nomogram was constructed based on ophthalmic events to predict the risk of POD. The study findings provide convincing evidence of the relationship between visual dysfunction and the risk of POD. In view of the higher risk of POD, visually impaired patients with PD should undergo closer monitoring after DBS surgery.

Risk Factors and Prognosis of Delirium After Liver Transplantation

To analyze the incidence, the onset time, and the risk factors of delirium after liver transplantation (LT). The clinical data of 211 patients who underwent LT at Third Xiangya Hospital, Central South University between January 2019 and December 2021 were collected to investigate the incidence and the onset time of postoperative delirium. Univariate analysis and multivariate logistic regression analysis were conducted to analyze the risk factors of delirium and to analyze the effect of delirium on clinical outcomes. The incidence of delirium was 20.4% (43/211) and the median interval between LT and the onset of delirium was 19 hours. Univariate analysis showed that the preoperative Model for End-Stage Liver Disease (MELD) score≥22, preoperative length-of-stay≥7, liver cancer, preoperative hepatic encephalopathy, infections within 2 months before LT, preoperative lymphocyte value<0.5×10 9 L －1, massive amount of intraoperative red blood cell infusion, and carbapenem antibiotics use for 3 days or longer were associated with postoperative delirium. Multivariate logistic regression analysis showed that preoperative infections within 2 months before LT (odds ratio [ OR]=2.597, 95% confidence interval [ CI]: 1.135-5.944, P=0.024), preoperative MELD score≥22 ( OR=2.967, 95% CI: 1.104-7.975, P=0.031), and preoperative hepatic encephalopathy ( OR=4.700, 95% CI: 2.043-10.602, P<0.001) were independent risk factors for delirium after LT, while carbapenems antibiotics use for 3 days or longer ( OR=0.192, 95% CI: 0.083-0.441, P<0.001) was a protective factor for postoperative delirium among LT recipients. Regarding clinical outcomes, patients with delirium had longer postoperative ICU length-of-stays than those without delirium did ( P=0.025). There is a high incidence of postoperative delirium among patients who undergo LT and the onset time of delirium after LT is early. Risk factors include preoperative infections, high MELD score, and hepatic encephalopathy. On the other hand, the use of carbapenems can help prevent delirium.

Faktori rizika za nastanak postoperativnog delirijuma

The occurrence of postoperative delirium (POD) has been recognized in recent decades as an important clinical syndrome, especially in elderly patients undergoing surgical treatment. The aim of this review was to examine the preoperative, intraoperative and postoperative factors that can lead to the occurrence of POD. The risk factors for developing POD are numerous, and most importantly, many can be modified. Some of the most significant risk factors for the occurrence of POD are older age, alcohol abuse, preoperatively worse functional and cognitive status, presence of depression and dementia. A higher incidence of POD was observed in patients undergoing more complex surgical procedures such as cardiac, vascular and orthopedic hip fracture operations. It was observed that after emergency surgical procedures POD occurs 1.5 to 3 times more often than during elective planned surgical procedures. Also, intraoperative bleeding and the application of transfusion were identified as significant risk factors for the occurrence of POD. In order to avoid cognitive deficits caused by longer exposure to anesthesia, research has shown that anesthetic titration by monitoring the bispectral index, as well as evoked auditory potentials, can reduce excessive exposure to anesthetics and thus reduce the risk of postoperative cognitive dysfunction. Knowledge of risk factors and identification of patients at increased risk are the basis of a strategy for the prevention of this syndrome. Current evidence suggests that perioperative avoidance of benzodiazepine use as well as adequate perioperative pain control are key measures to reduce the risk of POD.

Relationship of Postoperative Serum Neuro-Specific Enolase Levels with Postoperative Delirium Occurring after Microvascular Depression Surgery in Older Patients

There is a high incidence of postoperative delirium (POD) following microvascular decompression (MVD) surgery. Neuronal survival, differentiation, and neurite regeneration are regulated by neuro-specific enolase (NSE). Therefore, we investigated and assessed whether circulating NSE levels are related to POD after MVD surgery. We recruited a total of 209 patients and 209 age- and gender-matched healthy controls. A retrospective review of electronic medical records was conducted, and serum NSE levels were measured in the serum of patients before and after surgery, as well as the serum of controls. Patients were categorized according to the presence of POD. Postoperative patient serum levels of NSE were significantly higher compared to preoperative levels. Additionally, postoperative serum NSE levels were remarkably higher in POD patients than non-POD patients. In addition, there was no significant correlation between NSE levels and the type and severity of postoperative delirium. Age (OR = 1.153, 95% CI = 1.040–1.277, p = 0.006), the levels of serum NSE (OR = 1.326, 95% CI = 1.177–1.494, p &lt; 0.001), and the levels of serum S100β (OR = 1.006, 95% CI = 1.000–1.012, p = 0.048) were the three independent variables for predicting POD. A significant correlation existed between serum S100β levels and serum NSE levels (t = 2.690, p = 0.008). In terms of area under the precision–recall curve, the discriminatory ability of serum NSE levels (AUC = 0.876, 95% CI = 0.829–0.924, p &lt; 0.0001) was close to that of the serum S100β level (AUC = 0.879, 95% CI = 0.825–0.933, p &lt; 0.0001) and significantly higher than that of age (AUC = 0.813, 95% CI = 0.755–0.871, p &lt; 0.0001). Combining all three features produced a dramatic improvement over individual effects. The NSE level in serum was a stronger indicator of the likelihood of POD after MVD surgery in the older population. The clinical determination of this factor might be useful for distinguishing older patients at risk of POD after MVD surgery on the basis of their clinical findings.

Association of C-reactive protein to albumin ratio with postoperative delirium and mortality in elderly patients undergoing hip fracture surgery: A retrospective cohort study in a single large center

BackgroundPostoperative delirium is a common complication in elderly patients who have undergone hip fracture surgery. Since postoperative delirium is associated with poor outcomes and the treatment is very complicated, identifying the patients at high risk for delirium and providing more attentive care to prevent postoperative delirium is essential. In this study, we aimed to assess the association of an elevated C-reactive protein (CRP)/albumin ratio with the increased incidence of postoperative delirium in elderly people who had undergone hip fracture surgery. MethodsA total of 629 patients who underwent hip fracture surgery between January 2014 and December 2018 were retrospectively analyzed. Patients were classified into two groups according to preoperative CRP/albumin cut-off levels (<1.5 and ≥1.5). We performed a propensity score matching analysis to compare the incidence of postoperative delirium and overall mortality between the two groups. Multivariate logistic regression and Cox regression analyses were performed to examine the association of the preoperative CRP/albumin ratio with postoperative delirium and overall mortality. ResultsThere were significant differences in the incidence of postoperative delirium (18.0 % vs. 35.8 %, P < 0.001) and overall mortality (26.7 % vs. 46.9 %, P < 0.001) between the groups before matching. We also observed significant differences in the incidence of postoperative delirium (20.7 % vs. 32.7 %, P = 0.019) and overall mortality (34.7 % vs. 46.0 %, P = 0.046) between the groups after matching. A high CRP/albumin ratio (≥1.5) was significantly associated with a higher incidence of postoperative delirium (adjusted odds ratio [OR]: 2.11, 95 % confidence interval [CI]: 1.40–3.18, P < 0.001) and a higher rate of overall mortality (adjusted hazard ratio [HR]: 1.44, 95 % CI: 1.07–1.93, P = 0.015). ConclusionPreoperative CRP/albumin ratio might be an independent risk factor of postoperative delirium and surgical prognosis in elderly patients undergoing hip fracture surgery.

The Impact of Depression in Patients Undergoing Emergency Abdominal Surgery: An Exploratory Study.

Depression is associated with poorer outcomes in many disease states. However, its significance in abdominal surgery is unknown. This study investigated rates of depression in emergency abdominal surgery patients and its effects on outcomes. A retrospective cohort study was conducted across two UK sites and included all adult patients undergoing emergency abdominal surgery. Primary outcome was the complication rate in depressed patients, including the incidence of post-operative delirium. Secondary outcomes included mortality, time to oral intake and analgesia. Two hundred and ten patients were identified. The commonest indication for surgery was appendicitis (53.3%) followed by small bowel obstruction (9.5%). There was a 17% (n = 36) incidence of depression amongst patients, most of whom (n = 26, 72.2%) were taking antidepressants. Depression was associated with male sex (M:F 27:9 p = 0.003), higher median BMI (28 vs. 25 p = 0.013) and previous surgery (47.2% vs. 28.7% p = 0.032). Despite a higher incidence of post-operative delirium, increased time to oral analgesia and greater 30-day readmission rates in the depression cohort, multivariate analyses showed depression was not a significant independent predictor of these (OR 2.181, 95%CI 0.310-15.344; p = 0.433, OR 0.07, 95%CI 0.499-1.408; p = 0.348 and OR 1.367, 95%CI 0.102-18.34, respectively). Complication and mortality rates between depressed and non-depressed individuals were similar. Significant numbers of patients undergoing emergency abdominal surgery have depression, but this did not adversely affect post-operative outcomes. The study included relatively small numbers of participants undergoing procedures with straightforward recovery. Larger population studies are therefore required and should focus on investigating the association between major emergency surgeries with post-operative delirium and uncontrolled pain.

Relation between postoperative delirium and preoperative routine serum biomarkers

Background: Delirium is an acute and fluctuating change in the mental state characterised by diminished awareness and attention disturbance. Postoperative delirium (POD) is one of the most prevalent complications after surgery, especially in older indiviuals, and is related to a longer hospital stay and increased mortality.1 Although the cause of POD is less clear, several hypothesised causes include neuroinflammation, neurotransmitter imbalance, and oxidative stress, all of which may contribute to the pathophysiology of POD.2 This study aimed to investigate the relationship between routine preoperative blood inflammatory markers and POD, and the incidence and outcomes of POD. Methods: We included patients from the National Emergency Laparotomy Audit (NELA) database aged ≥65 yr at the time of operation at Queen Elizabeth Hospital, Birmingham, UK. The study was conducted prospectively and retrospectively. In the prospective part, we screened the patients for delirium 5 days postoperatively using the modified Richmond Agitation Sedation Scale (mRASS), Confusion Assessment Method for ICU (CAM-ICU),3 and patient notes. Retrospectively, the clinical notes were scanned for keywords according to a validated chart abstraction method.4 We applied the Diagnostic and Statistical Manual of Mental Disorders V (DSM-V) criteria to diagnose POD in those who screened positive. We documented the preoperative blood results, including haemoglobin, white blood cells (WBCs), neutrophils, lymphocytes, platelets, neutrophil/lymphocyte ratio (NLR), urea, creatinine, and lactate. Multivariate logistic regression analyses were performed. Results: POD was diagnosed in 49 of 164 patients (29.9%). Sepsis, renal disease, and higher ASA grade and NELA mortality scores were significantly related to POD incidence. Statistical analysis showed a significant relation between POD and higher levels of preoperative urea, C-reactive protein (CRP), CRP/albumin ratio (CAR), NLR, and platelet/lymphocyte ratio (PLR). Furthermore, low levels of haemoglobin and albumin were significantly associated with POD. POD patients required significantly longer hospital stays with higher mortality. Multivariate logistic regression analysis demonstrated that age >75 yr, sepsis, and high preoperative PLR are independent risk factors for POD. Conclusions: Higher preoperative CAR, PLR, and NLR were associated with a higher incidence of POD in patients aged ≥65 yr undergoing emergency laparotomy. Our study supports that preoperative inflammatory status can be linked to POD. Knowing the mechanisms and risk factors can help clinicians to decrease POD incidence. 1.Aldecoa C, Bettelli G, Bilotta F, et al. Eur J Anaesth 2017; 34: 192–2142.Moppett I, Noah A. Br J Anaesth 2021; 127: 424–343.Oh ES, Fong TG, Hsieh TT, Inouye SK. JAMA 2017; 318: 1161–744.Kuhn E, Lorenz R, Banaschewski T, et al. PloS One 2014; 9: e91506

Edmonton frailty scale score predicts postoperative delirium: a retrospective cohort analysis

BackgroundFrailty has been associated with postoperative delirium (POD). Studies suggest that the Fried phenotype has a stronger association with POD than the Edmonton Frailty Scale (EFS) criteria. Although phenotypic frailty is recognized as a good predictor of delirium, the EFS has higher ratings for feasibility in the surgical setting. Thus, our aim was to determine the association between EFS-assessed vulnerability and POD in an elective surgical population of older adults. A secondary aim was to determine which domains assessed by the EFS were closely associated with POD.MethodsAfter IRB approval was received, electronic medical records of surgical patients at our institution were downloaded from 12/1/2018 to 3/1/2020. Inclusion criteria included age ≥ 65 years, preoperative EFS assessment within 6 months of surgery, elective surgery not scheduled for intensive care unit (ICU) stay but followed by at least 1 day postoperative stay, and at least two in-hospital evaluations with the 4 A’s test (arousal, attention, abbreviated mental test-4, acute change [4AT]) on the surgical ward. Vulnerability was determined by EFS score ≥ 6. Patients were stratified into two groups according to highest postoperative 4AT score: 0–3 (no POD) and ≥ 4 (POD). Odds of POD associated with EFS score ≥ 6 were evaluated by using logistic regression adjusted for potential confounders.ResultsThe dataset included 324 patients. Vulnerability was associated with higher incidence of POD (p = 0.0007, Fisher’s exact). EFS ≥6 was consistently associated with POD in all bivariate models. Vulnerability predicted POD in multivariable modeling (OR = 3.5, 95% CI 1.1 to 11.5). Multivariable analysis of EFS domains revealed an overall trend in which higher scores per domain had a higher odds for POD. The strongest association occurred with presence of incontinence (OR = 3.8, 95% CI 1.2 to 11.0).ConclusionsEFS criteria for vulnerability predict POD in older, non-ICU patients undergoing elective surgery.

Elevated Substance P Is a Risk Factor for Postoperative Delirium in Patients with Hip Fracture.

Objective Hip fractures are quite common worldwide, especially among the elderly, and are associated with a high incidence of postoperative delirium, which worsens functional results and increases death. The causes of postoperative delirium in patients with hip fractures are unknown, and a separate pathobiology has been hypothesized. Substance P is a neuropeptide that has been linked to a number of immune-inflammatory and neurological conditions. The purpose of this study was to see if serum substance P levels could predict postoperative delirium in a group of hip fracture patients. Methods A total of 148 hip fracture patients were enrolled in the study, all of whom had no substantial pre-existing medical or cognitive issues. Demographic and regular laboratory data were gathered as a starting point. ELISA was used to examine substance P levels before and after surgery (after 1 day). Patients were then divided into two groups: “postoperative delirium” and “no postoperative delirium.” Intergroup comparisons, study of delirium prevalence rates in postoperative serum substance P quartile categories, and binary logistic regression for postoperative delirium category as outcome were all done. Results Except for serum low-density lipoprotein (LDL) levels, there were no statistically significant variations in preoperative substance P levels or other baseline characteristics between the two groups. The “postoperative delirium” group had significantly higher postoperative substance P levels than the “no postoperative delirium” group (46.36.1 versus 31.94.7 pg/ml). There was a significant difference in postoperative delirium rates between the quartile categories of postoperative substance P, with the fourth quartile having the highest rate. Regression analysis revealed that postoperative substance P levels were related with a significantly increased OR (1.265, CI: 1.172-1.283) of postoperative delirium. Conclusion In the current sample of hip fracture patients, a higher postoperative serum substance P level was linked to a higher risk of postoperative delirium. Further research into the utility of early postoperative serum substance P as a delirium indicator in hip fracture patients is needed.

Gender Differences and Postoperative Delirium in Adult Patients Undergoing Cardiac Valve Surgery.

Background: Postoperative delirium (POD) is common in patients following cardiac surgery. According to studies on non-cardiac surgery, males suffered from higher incidence of POD. However, there is no report about effect of gender differences on POD occurrence in cardiac surgery patients. The aim of this study was to investigate the effect of gender differences on POD occurrence in adult patients after cardiac valve surgery.Methods: This is a retrospective case-control study. We recorded the clinical data in adult patients who underwent elective cardiac valve surgery from May 2019 to October 2020. POD was assessed by the Confusion Assessment Method for Intensive Care Unit. Univariate analysis was used to screen the potential risk factors. Collinearity analysis was conducted to detect overlapping predictor variables on the outcomes. A multivariate logistic regression with odds ratio (OR) and 95% confidence interval (CI) was used to identify the independent risk factors. The Hosmer-Lemeshow test was performed to show the good calibration of the logistic regression model.Results: In total, we recorded the perioperative data in 431 adult patients, including 212 males and 219 females. Sixty patients suffered from POD, including 39 males and 21 females. Twenty-one perioperative variables were selected, and 11 were screened by univariate analysis. We did not detect the severe collinearity among the 11 variables. Male gender was identified as a significant risk factor in POD occurrence in patients undergoing cardiac surgery (Adjusted OR: 2.213, 95% CI: 1.049–4.670, P = 0.037). The Hosmer-Lemeshow test demonstrated good calibration of the logistic regression model (χ2 = 7.238, P = 0.511). Besides, compared with females, the relationship of male and delirium subtypes was as follows: (1) hyperactive: adjusted OR: 3.384, 95% CI: 1.335–8.580, P = 0.010; (2) hypoactive: adjusted OR: 0.509, 95% CI: 0.147–1.766, P = 0.287. A Stratification analysis by age demonstrated that the males showed higher POD incidence in patients aged younger than 60 years (adjusted OR: 4.384, 95% CI: 1.318–14.586, P = 0.016).Conclusions: Male gender is an important risk factor in POD occurrence in patients following cardiac surgery. Furthermore, the incidence of hyperactive delirium is higher in males. Besides, the male patients aged younger than 60 years are at high risk of POD. We should pay more attention to the male patients to prevent their POD occurrence.

Postoperative delirium and quality of life after transcatheter and surgical aortic valve replacement: A prospective observational study

ObjectiveIn older patients, postoperative delirium is a frequently occurring complication after surgical aortic valve replacement, leading to an excess in postoperative morbidity and mortality. It remains controversial whether transcatheter aortic valve implantation and minimally invasive surgical aortic valve replacement can reduce the risk of postoperative delirium. This study aimed to compare the incidence of postoperative delirium after transcatheter aortic valve implantation and surgical aortic valve replacement and the impact on long-term outcomes. MethodsBetween September 2018 and January 2020, we conducted an observational, prospective cohort study in patients aged 70 years or more undergoing transcatheter aortic valve implantation or surgical aortic valve replacement. The primary end point was the incidence of in-hospital postoperative delirium during 5 postoperative days assessed with the Confusion Assessment Method. Secondary end points included perioperative inflammation, postoperative complications, health status (EuroQol 5-dimensional questionnaire 5 levels), and mortality up to 6 months. Transcatheter aortic valve implantation and surgical aortic valve replacement were compared using propensity weighting to account for important baseline differences (European System for Cardiac Operative Risk Evaluation II, age, and frailty). ResultsWe included 250 patients with a mean (standard deviation) age of 80 (±5.8) years and a European System for Cardiac Operative Risk Evaluation score of 5 (±4.7). In the propensity-weighted analysis, those undergoing surgical aortic valve replacement (N = 166) had a higher incidence of postoperative delirium compared with transcatheter aortic valve implantation (N = 84) (51% vs 15%: P < .0001). Furthermore, patients undergoing surgical aortic valve replacement experienced more inflammation, a greater depth of anesthesia, and more intraoperative hypotension. After surgical aortic valve replacement, 41% of patients experienced an improved health status compared with 12% after transcatheter aortic valve implantation (P < .0001). No outcome differences were noted within the surgical aortic valve replacement groups. ConclusionsTranscatheter aortic valve implantation is associated with a lower risk for postoperative delirium. Nevertheless, patients undergoing surgical aortic valve replacement experience the greatest improvement in quality of life. Heart teams should consider these outcomes in shared decision-making in the choice of transcatheter aortic valve implantation or surgical aortic valve replacement.

Reply to: assessing risk factors of delirium and its effects on adverse outcomes in patients admitted to the ICU after craniotomy

Editor, We thank Wan et al.1 for their interest in our cohort study on postoperative delirium in patients admitted to the ICU after intracranial surgery2 and appreciate the opportunity to respond. For the diagnosis of postoperative delirium, the Diagnostic and Statistical Manual of Mental Disorders (DSM), fifth edition nomenclature is recommended.3 However, to assist nonpsychiatrically trained clinicians to identify delirium quickly and accurately, several DSM-based instruments have been developed, including the Confusion Assessment Method (CAM)4 and CAM for the ICU (CAM-ICU).5 We used the CAM-ICU for several reasons. All enrolled patients were transferred to the ICU after craniotomy, and all assessments of postoperative delirium were performed in the ICU on postoperative day 1. In our cohort, 2.2% of the patients (18/800, Table 4) were mechanically ventilated when assessing delirium on postoperative day 1, but 27.5% of the patients (220/800, unpublished data used in immobilising factor score) were intubated. As the most widely recognised screening scale of postoperative delirium in the ICU, CAM-ICU is recommended by the American Society of Critical Care Medicine as a delirium assessment tool in adult patients in the ICU6 and is suggested by the European Society of Anaesthesiology as a postoperative delirium screening tool in postoperative patients.7 Therefore, in many cohort and controlled studies, CAM-ICU has been employed as an effective tool for the assessment of postoperative delirium in the ICU.8–11 We agree with Wan et al. that in our study, the incidence of postoperative delirium may have been confounded by the assessment tool and the time window for the monitoring. As we discussed in our article, although previous studies reported that the incidence of postoperative delirium decreased in a time-dependent manner, delirium may occur from postoperative day 4 to day 7 (but less than 5%).11,12 Furthermore, it has been reported that, compared with the Diagnostic and Statistical Manual of the American Psychiatric Association, the sensitivity of CAM-ICU to detect delirium is relatively low in the recovery room setting.7 All these factors may have caused an underestimation of the incidence of postoperative delirium in our cohort. Therefore, our results still indicate the importance of postoperative delirium in the population we studied. Regarding the analysis of risk factors for postoperative delirium, we did follow the overall strategy univariate analyses first (Tables 1 to 4), followed by multivariate analyses (Table 5). Wan et al. may have some misunderstanding of univariate analysis. The main purpose of the univariate analysis is to identify candidate risk factors or covariates, rather than to estimate the size of the effect [the odds ratio (OR) and its 95% confidence interval (CI) were calculated in our study]. Therefore, we can either examine the distribution of variables between the groups or use one independent variable at a time to fit a regression model to identify potential risk factors. We prefer the former because this form of data is more informative with the summary and report of descriptive statistics and the P value in statistical tests. As for the estimation of the effect size, we reported the original and adjusted ORs and 95% CIs of the risk factors in the multivariate logistic regression model in Table 5. These factors are more valuable for preventing postoperative delirium. For more detailed information about our statistical strategy, please refer to other reports.13,14 We used backward stepwise variable selection in multivariate logistic regression because this method can obtain a performance similar to the Bootstrap method, but it is easy to perform.15 We agree with Wan et al. that a number of demographic and peri-operative factors may lead to adverse postoperative outcomes. That is why we did not take the causal relationship between postoperative delirium and adverse consequences as the end point of the study. As we pointed out in the article,2 our data show the potential association between postoperative delirium and adverse outcomes. Considering the relatively high incidence of postoperative delirium and the identified risk factors, our study indicates a comprehensive strategy to prevent postoperative delirium after intracranial surgery. In summary, one study cannot solve all problems. We thank Wan et al. for their suggestions for identifying and investigating safe and effective interventions to reduce the incidence, duration and severity of postoperative delirium, which might provide the readers with more information. With the help of all the readers, we will keep working on postoperative delirium issues to figure it out.

Comparison of One-day Combined versus Staged Anterior and Posterior Cervical Decompression, Fixation, and Fusion.

To compare the perioperative outcomes between single-day combined or separate-day staged surgeries for cervical spinal stenosis. A retrospective cohort analysis was conducted on consecutive patients admitted at a single institution between July 2015 and April 2019, who underwent either single-day combined or separate-day staged surgeries during the same hospitalization period. Demographics, comorbidities, hospital length of stay, and perioperative complications were compared between the patient groups. Eighty patients (combined surgery: n=68, staged surgery: n=12) were included. Dysphagia was the most commonly reported postoperative complication in 44/80 patients (55%). There were no significant differences in the baseline demographics between the two groups. The staged surgery group had significantly longer total time in the operating room (7.2 vs. 8.5 hours, p=0.002), longer duration of general anesthesia (6.7 vs. 7.6 hours, p=0.006), and higher incidence of postoperative delirium (12.1% vs. 50% p=0.005) than the combined surgery group. The mean hospital length of stay was similar in the two groups (combined surgery: 7.5 days vs. staged surgery: 15.1 days, p=0.09). Staged anterior and posterior cervical decompressions, stabilizations, and fusions are associated with longer total time in the operating room, longer duration of general anesthesia, and higher incidence of postoperative delirium than combined surgeries.