Risk Factors for Delirium after Vascular Surgery:A Systematic Review and Meta-Analysis

Background: Vascular surgery is considered a risk factor for the development of postoperative delirium (POD). In this systematic review we provide a report on the incidence and risk-factors of POD after vascular surgery. Methods: A systematic literature search was conducted using Pubmed with the MeSH terms and key words "delirium" or "confusion", "vascular surgery procedures" and "risk factors or "risk assessment". Studies were selected for review after meeting the following inclusion cr iter ia: vascular surgery, POD diagnosed using validated screening tools, and DSM-derived criteria to assess delirium. A meta-analysis was performed for each endpoint if at least two studies could be combined. Results: Sixteen articles met the abovementioned cr iter ia. The incidence of delir ium ranged from 5% to 39%. Various preoperative risk factors were identified that is, age (Random MD 3.96, CI 2.57-5.35), hypertension (Fixed OR 1.30, CI 1.05-1.59), diabetes mellitus (Random OR 2.15, CI 1.30-3.56), hearing impairment (Fixed OR 1.89, CI 1.28-2.81), history of cerebrovascular incident or transient ischemic attack (Fixed OR 2.20, CI 1.68-2.88), renal failure (Fixed OR 1.61, CI 1.19-2.17), and pre-operative low haemoglobin level (fixed MD-0.76, CI-1.04 to-0.47). Intra-operative risk factors were duration of surgery (Random MD 15.68; CI 2.79-28.57), open aneurysm repair (Fixed OR 4.99, CI 3.10-8.03), aortic cross clamping time (fixed MD 7.99, CI 2.56-13.42), amputation surgery (random OR 3.77, CI 2.13-6.67), emergency surgery (Fixed OR 4.84, CI 2.81-8.32) and total blood loss (Random MD 496.5, CI 84.51-908.44) and need for blood transfusion (Random OR 3.72, CI 1.57-8.80). Regional anesthesia on the other hand, had a protective effect. Delirium was associated with longer ICU and hospital length of stay, and more frequent discharge to a care facility. Conclusions: POD after vascular surgery is a frequent complication and effect-size pooling supports the concept that delirium is a heterogeneous disorder. The risk factors identified can be used to either design a validated risk factor model or individual preventive strategies for high-risk patients

Feasibility study of computed tomography colonography using limited bowel preparation at normal and low-dose levels study

The purpose was to evaluate low-dose CT colonography without cathartic cleansing in terms of image quality, polyp visualization and patient acceptance. Sixty-one patients scheduled for colonoscopy started a low-fiber diet, lactulose and amidotrizoic-acid for fecal tagging 2 days prior to the CT scan (standard dose, 5.8–8.2 mSv). The original raw data of 51 patients were modified and reconstructed at simulated 2.3 and 0.7 mSv levels. Two observers evaluated the standard dose scan regarding image quality and polyps. A third evaluated the presence of polyps at all three mSv levels in a blinded prospective way. All observers were blinded to the reference standard: colonoscopy. At three times patients were given questionnaires relating to their experiences and preference. Image quality was sufficient in all patients, but significantly lower in the cecum, sigmoid and rectum. The two observers correctly identified respectively 10/15 (67%) and 9/15 (60%) polyps ≥10 mm, with 5 and 8 false-positive lesions (standard dose scan). Dose reduction down to 0.7 mSv was not associated with significant changes in diagnostic value (polyps ≥10 mm). Eighty percent of patients preferred CT colonography and 13% preferred colonoscopy (P<0.001). CT colonography without cleansing is preferred to colonoscopy and shows sufficient image quality and moderate sensitivity, without impaired diagnostic value at dose-levels as low as 0.7 mSv

Predicting postoperative delirium after vascular surgical procedures

Objective: The objective of this study was to determine the incidence of and specific preoperative and intraoperative risk factors for postoperative delirium (POD) in electively treated vascular surgery patients. Methods: Between March 2010 and November 2013, all vascular surgery patients were included in a prospective database. Various preoperative, intraoperative, and postoperative risk factors were collected during hospitalization. The primary outcome variable was the incidence of POD. Secondary outcome variables were any surgical complication, hospital length of stay, and mortality. Results: In total, 566 patients were prospectively evaluated; 463 patients were 60 years or older at the time of surgery and formed our study cohort. The median age was 72 years (interquartile range, 66-77), and 76.9% were male. Twenty-two patients (4.8%) developed POD. Factors that differed significantly by univariate analysis included current smoking (P = .001), increased comorbidity (P = .001), hypertension (P = .003), diabetes mellitus (P = .001), cognitive impairment (P <.001), open aortic surgery or amputation surgery (P <.001), elevated C-reactive protein level (P <.001), and blood loss (P <.001). Multivariate logistic regression analysis revealed preoperative cognitive impairment (odds ratio [OR], 16.4; 95% confidence interval [CI], 4.7-57.0), open aortic surgery or amputation surgery (OR, 14.0; 95% CI, 3.9-49.8), current smoking (OR, 10.5; 95% CI, 2.8-40.2), hypertension (OR, 7.6; 95% CI, 1.9-30.5) and age >= 80 years (OR, 7.3; 95% CI, 1.8-30.1) to be independent predictors of the occurrence of POD. The combination of these parameters allows us to predict delirium with a sensitivity of 86% and a specificity of 92%. The area under the curve of the corresponding receiver operating characteristics was 0.93. Delirium was associated with longer hospital length of stay (P <.001), more frequent and increased intensive care unit stays (P = .008 and P = .003, respectively), more surgical complications (P <.001), more postdischarge institutionalization (P Conclusions: In vascular surgery patients, preoperative cognitive impairment and open aortic or amputation surgery were highly significant risk factors for the occurrence of POD. In addition, POD was significantly associated with a higher mortality and more institutionalization. Patients with these risk factors should be considered for high-standard delirium care to improve these outcomes

Association of Hospital Volume with Perioperative Mortality of Endovascular Repair of Complex Aortic Aneurysms: A Nationwide Cohort Study

Objective: We evaluate nationwide perioperative outcomes of complex EVAR and assess the volume-outcome association of complex EVAR. Summary of Background Data: Endovascular treatment with fenestrated (FEVAR) or branched (BEVAR) endografts is progressively used for excluding complex aortic aneurysms (complex AAs). It is unclear if a volumeoutcome association exists in endovascular treatment of complex AAs (complex EVAR). Methods: All patients prospectively registered in the Dutch Surgical Aneurysm Audit who underwent complex EVAR (FEVAR or BEVAR) between January 2016 and January 2020 were included. The effect of annual hospital volume on perioperative mortality was examined using multivariable logistic regression analyses. Patients were stratified into quartiles based on annual hospital volume to determine hospital volume categories. Results: We included 694 patients (539 FEVAR patients, 155 BEVAR patients). Perioperative mortality following FEVAR was 4.5% and 5.2% following BEVAR. Postoperative complication rates were 30.1% and 48.7%, respectively. The first quartile hospitals performed <9 procedures/ yr; second, third, and fourth quartile hospitals performed 9-12, 13-22, and 23 procedures/yr. The highest volume hospitals treated significantly more complex patients. Perioperative mortality of complex EVAR was 9.1% in hospitals with a volume of <9, and 2.5% in hospitals with a volume of 13 (P = 0.008). After adjustment for confounders, an annual volume of 13 was associated with less perioperative mortality compared to hospitals with a volume of <9. Conclusions: Data from this nationwide mandatory quality registry shows a significant effect of hospital volume on perioperative mortality following complex EVAR, with high volume complex EVAR centers demonstrating lower mortality rates