Risk factors for postoperative delirium after colorectal surgery for carcinoma

Intraoperative hypotension is associated with decreased long-term survival in older patients after major noncardiac surgery: Secondary analysis of three randomized trials

STUDY OBJECTIVE

To assess the association of intraoperative hypotension with long-term survivals in older patients after major noncardiac surgery mainly for cancer.

DESIGN

A secondary analysis of databases from three randomized trials with long-term follow-up.

SETTING

The underlying trials were conducted in 17 tertiary hospitals in China.

PATIENTS

Patients aged 60 to 90 years who underwent major noncardiac thoracic or abdominal surgeries (≥ 2 h) in a single center were included in this analysis.

EXPOSURES

Restricted cubic spline models were employed to determine the lowest mean arterial pressure (MAP) threshold that was potentially harmful for long-term survivals. Patients were arbitrarily divided into three groups according to the cumulative duration or area under the MAP threshold. The association between intraoperative hypotension exposure and long-term survivals were analyzed with the Cox proportional hazard regression models.

MEASUREMENTS

Our primary endpoint was overall survival. Secondary endpoints included recurrence-free and event-free survivals.

MAIN RESULTS

A total of 2664 patients (mean age 69.0 years, 34.9% female sex, 92.5% cancer surgery) were included in the final analysis. MAP < 60 mmHg was adopted as the threshold of intraoperative hypotension. Patients were divided into three groups according to duration under MAP < 60 mmHg (<1 min, 1-10 min, and > 10 min) or area under MAP <60 mmHg (< 1 mmHg⋅min, 1-30 mmHg⋅min, and > 30 mmHg⋅min). After adjusting confounders, duration under MAP < 60 mmHg for > 10 min was associated with a shortened overall survival when compared with the < 1 min patients (adjusted hazard ratio [HR] 1.31, 95% confidence interval [CI] 1.09 to 1.57, P = 0.004); area under MAP < 60 mmHg for > 30 mmHg⋅min was associated with a shortened overall survival when compared with the < 1 mmHg⋅min patients (adjusted HR 1.40, 95% CI 1.16 to 1.68, P < 0.001). Similar associations exist between duration under MAP < 60 mmHg for > 10 min or area under MAP < 60 mmHg for > 30 mmHg⋅min and recurrence-free or event-free survivals.

CONCLUSIONS

In older patients who underwent major noncardiac surgery mainly for cancer, intraoperative hypotension was associated with worse overall, recurrence-free, and event-free survivals.

Preoperative cognitive function as a risk factor of postoperative delirium in cancer surgeries: A systematic review and meta-analysis

Postoperative delirium (POD) after cancer surgeries can be a result of chemo brain, anesthesia, surgery duration, and preoperative cognitive impairment. Although older age and preoperative cognitive dysfunction were reported to increase the risk of POD in noncardiac surgery, the role of preoperative cognitive function and age in the development of POD after all types of cancer surgeries is not clear. This study aimed to determine the relationship between preoperative cognitive function and likelihood of POD after cancer surgeries. This study used three main online databases and followed PRISMA guidelines. English language original articles that examined preoperative cognitive function before solid tumor cancer surgery and assessed patients for postoperative delirium were included. We employed the random effect meta-analysis method. The overall incidence of POD ranged from 8.7% to 50.9%. The confusion assessment method was the most common tool used to assess delirium. Mini-mental state evaluation (MMSE), Mini-cog, and Montreal cognitive assessment were the most common tools to assess cognitive function. The pooled (total observation = 4676) random effects SMD was estimated at -0.84 (95% confidence interval [CI]: -1.30 to -0.31), indicating that lower MMSE scores before surgery are associated with a higher risk of POD. The pooled (total observation = 2668) random effects OR was estimated at 5.17 (95% CI: 2.51 to -10.63), indicating preoperative cognitive dysfunction can significantly predict the occurrence of POD after cancer surgeries. In conclusion, preoperative cognitive function is an independent and significant predictor of POD after solid tumor cancer surgeries.

Association of Blood Pressure Variability with Delirium in Patients with Critical Illness

BACKGROUND

The objective was to examine the association of blood pressure variability (BPV) during the first 24 h after intensive care unit admission with the likelihood of delirium and depressed alertness without delirium ("depressed alertness").

METHODS

This retrospective, observational, cohort study included all consecutive adult patients admitted to an intensive care unit at Mayo Clinic, Rochester, Minnesota, from July 1, 2004, through October 31, 2015. The primary outcomes were delirium and delirium-free days, and the secondary outcomes included depressed alertness and depressed alertness-free days. Logistic regression was performed to determine the association of BPV with delirium and depressed alertness. Proportional odds regression was used to assess the association of BPV with delirium-free days and depressed alertness-free days.

RESULTS

Among 66,549 intensive care unit admissions, delirium was documented in 20.2% and depressed alertness was documented in 24.4%. Preserved cognition was documented in 55.4% of intensive care unit admissions. Increased systolic and diastolic BPV was associated with an increased odds of delirium and depressed alertness. The magnitude of the association per 5-mm Hg increase in systolic average real variability (the average of absolute value of changes between consecutive systolic blood pressure readings) was greater for delirium (odds ratio 1.34; 95% confidence interval 1.29-1.40; P < 0.001) than for depressed alertness (odds ratio 1.06; 95% confidence interval 1.02-1.10; P = 0.004). Increased systolic and diastolic BPV was associated with fewer delirium-free days but not with depressed alertness-free days.

CONCLUSIONS

BPV in the first 24 h after intensive care unit admission is associated with an increased likelihood of delirium and fewer delirium-free days.

Incidence of delirium in older people with cancer: Systematic review and meta-analysis

PURPOSE

Delirium is a prevalent neuropsychiatric syndrome in older people with cancer. However, there are no meta-analyses assessing its incidence exclusively in this population. This study aims to assess the incidence proportion of delirium in older people with cancer in the hospital area.

METHODS

A systematic review and meta-analysis were carried out. MEDLINE, Scopus, and EBSCO were searched from inception to December 2021. PRISMA guidelines were followed. Inclusion criteria were original peer-reviewed studies with experimental (randomised controlled trials), observational, and cross-sectional designs assessing delirium older inpatients (≥65 years) with oncological diseases in medical and post-surgical hospital areas and using validated screening or diagnostic methods. A web-based system was used to manage the screening process. Study quality was assessed with Joanna Briggs Institute Critical Appraisal tools. The statistical analysis was performed in RevMan v5.4.0 (Cochrane Collaboration, Oxford, UK), using a random-effects model to calculate incidence and 95% confidence intervals (CIs).

RESULTS

Based on 37 included articles, the incidence proportion of delirium ranged from 3.8% to 61.4%, in a total of 11,847 older patients with cancer. Meta-analysis showed a pooled incidence of 22.6% (95% confidence interval 18.5%, 26.7%; I2 = 97%, p < 0.001). The main tools for detection were the Diagnostic Statistical Manual criteria and the Confusion Assessment Methods scale.

CONCLUSIONS

The incidence proportion of delirium in older inpatients with cancer is 22.6%. Incidence in the medical setting was higher than in the post-surgical areas. There is a need for high-quality studies examining delirium in older people with cancer.

Influence of perioperative blood pressure regulation on postoperative delirium in patients undergoing head and neck free flap reconstruction

BACKGROUND

Postoperative delirium (POD) is a serious complication in patients undergoing microvascular head and neck reconstruction. Whether intraoperative and postoperative blood pressure regulation are risk factors for POD remains unclear. This study aimed to highlight the relationships between intraoperative and postoperative blood pressure regulation and POD in microvascular head and neck reconstruction.

METHODS

Data from 433 patients who underwent microvascular head and neck reconstruction at our department of oral and maxillofacial surgery between 2011 and 2019 were retrospectively analyzed. The 55 patients with POD were matched with 55 patients without POD in terms of tracheotomy, flap type, and flap location, and the intraoperative and postoperative systolic and mean blood pressure values were compared between the two groups.

RESULTS

Patients with POD showed lower intraoperative and postoperative minimum mean arterial pressure (MAP) values than patients without POD (60.0 mmHg vs. 65.0 mmHg, p < 0.001; and 56.0 mmHg vs. 62.0 mmHg, p < 0.001; respectively). A lower intraoperative minimum MAP value was identified as predictor for POD (odds ratio [OR] 1.246, 95% confidence interval [CI] 1.057-1.472, p = 0.009). The cut-off value for intraoperative MAP for predicting POD was  ≤ 62.5 mmHg (area under the curve [AUC] 0.822, 95% CI 0.744-0.900, p < 0.001).

CONCLUSIONS

Maintaining a stable intraoperative minimum MAP of  > 62.5 mmHg could help to reduce the incidence of POD in microvascular head and neck reconstruction.

A revision of JPOS/JASCC clinical guidelines for delirium in adult cancer patients: a summary of recommendation statements

OBJECTIVE

The Japanese Psycho-Oncology Society and the Japanese Association of Supportive Care in Cancer have recently revised the clinical practice guidelines for delirium in adult cancer patients. This article reports the process of developing the revised guidelines and summarizes the recommendations made.

METHODS

The guidelines were developed in accordance with the Medical Information Network Distribution Service creation procedures. The guideline development group, consisting of multi-disciplinary members, created three new clinical questions: non-pharmacological intervention and antipsychotics for the prevention of delirium and trazodone for the management of delirium. In addition, systematic reviews of nine existing clinical questions have been updated. Two independent reviewers reviewed the proposed articles. The certainty of evidence and the strength of the recommendations were graded using the grading system developed by the Medical Information Network Distribution Service, following the concept of The Grading of Recommendations Assessment, Development, and Evaluation system. The modified Delphi method was used to validate the recommended statements.

RESULTS

This article provides a compendium of the recommendations along with their rationales, as well as a short summary.

CONCLUSIONS

These revised guidelines will be useful for the prevention, assessment and management of delirium in adult cancer patients in Japan.

Incidence of postoperative delirium in older adults undergoing surgical procedures: A systematic literature review and meta-analysis

BACKGROUND

With the increase in life expectancy around the globe, the incidence of postoperative delirium (POD) among older people (≥65 years) is growing. Previous studies showed a wide variation in the incidence of POD, from 4% to 53%, with a lack of specific evidence about the incidence of POD by specific surgery type among older people. The aim of this systematic review and meta-analysis was to determine the incidence of POD by surgery type within populations 65 years and over.

METHODS

Databases including PubMed, Cochrane library, Embase, and CINAHL were searched until October 2020. Due to the relatively higher number of meta-analyses undertaken in this area of research, a streamlined systematic meta-analysis was proposed.

RESULTS

A total of 28 meta-analyses (comprising 284 individual studies) were reviewed. Data from relevant individual studies (n = 90) were extracted and included in the current study. Studies were grouped into eight surgery types and the incidence of POD for orthopedic, vascular, spinal, cardiac, colorectal, abdominal, urologic, and mixed surgeries was 20%, 14%, 13%, 32%, 14%, 30%, 10%, and 26%, respectively. POD detection instruments were different across the studies, with Confusion Assessment Method (CAM & CAM-ICU) being the most frequently adopted.

LINKING EVIDENCE TO ACTION

This study showed that POD incidence in older people undergoing surgery varied widely across surgery type. The more complex surgeries like cardiac and abdominal surgeries were associated with a higher risk of POD. This highlights the need to include the level of surgery complexity as a risk factor in preoperative assessments.

Association of intraoperative hypotension and severe postoperative complications during non-cardiac surgery in adult patients: A systematic review and meta-analysis

Background

Intraoperative hypotension (IOH) is a common side effect of non-cardiac surgery that might induce poor postoperative outcomes. The relationship between the IOH and severe postoperative complications is still unclear. Thus, we summarized the existing literature to evaluate whether IOH contributes to developing severe postoperative complications during non-cardiac surgery.

Methods

We conducted a comprehensive search of PubMed, Embase, Cochrane Library, Web of Science, and the CBM from inception to 15 September 2022. The primary outcomes were 30-day mortality, acute kidney injury (AKI), major adverse cardiac events (myocardial injury or myocardial infarction), postoperative cognitive dysfunction (POCD), and postoperative delirium (POD). Secondary outcomes included surgical-site infection (SSI), stroke, and 1-year mortality.

Results

72 studies (3 randomized; 69 non-randomized) were included in this study. Low-quality evidence showed IOH resulted in an increased risk of 30-day mortality (OR, 1.85; 95% CI, 1.30-2.64; P < .001), AKI (OR, 2.69; 95% CI, 2.15-3.37; P < .001), and stroke (OR, 1.33; 95% CI, 1.21-1.46; P < .001) after non-cardiac surgery than non-IOH. Very low-quality evidence showed IOH was associated with a higher risk of myocardial injury (OR, 2.00; 95% CI, 1.17-3.43; P = .01), myocardial infarction (OR, 2.11; 95% CI, 1.41-3.16; P < .001), and POD (OR, 2.27; 95% CI, 1.53-3.38; P < .001). Very low-quality evidence showed IOH have a similar incidence of POCD (OR, 2.82; 95% CI, 0.83-9.50; P = .10) and 1-year-mortality (OR, 1.66; 95% CI, 0.65-4.20; P = .29) compared with non-IOH in non-cardiac surgery.

Conclusion

Our results suggest IOH was associated with an increased risk of severe postoperative complications after non-cardiac surgery than non-IOH. IOH is a potentially avoidable hazard that should be closely monitored during non-cardiac surgery.

Preoperative Risk Factors Associated with Increased Incidence of Postoperative Delirium: Systematic Review of Qualified Clinical Studies

Postoperative delirium (POD) is an acute alteration of mental state, characterized by reduced awareness and attention, occurring up to five postoperative days after recovery from anesthesia. Several original studies and reviews have identified possible perioperative POD risk factors; however, there is no comprehensive review of the preoperative risk factors in patients diagnosed with POD using only validated diagnostic scales. The aim of this systematic review was to report the preoperative risk factors associated with an increased incidence of POD in patients undergoing non-cardiac and non-brain surgery. The reviewed studies included original research papers that used at least one validated diagnostic scale to identify POD occurrence for more than 24 h. A total of 6475 references were retrieved from the database search, with only 260 of them being suitable for further review. Out of the 260 reviewed studies, only 165 that used a validated POD scale reported one or more preoperative risk factors. Forty-one risk factors were identified, with various levels of statistical significance. The extracted risk factors could serve as a preoperative POD risk assessment workup. Future studies dedicated to the further evaluation of the specific preoperative risk factors' contributions to POD could help with the development of a weighted screening tool.

Reported definitions of intraoperative hypotension in adults undergoing non-cardiac surgery under general anaesthesia: a review

Background

Intraoperative hypotension (IOH) during non-cardiac surgery is common and associated with major adverse kidney, neurological and cardiac events and even death. Given that IOH is a modifiable risk factor for the mitigation of postoperative complications, it is imperative to generate a precise definition for IOH to facilitate strategies for avoiding or treating its occurrence. Moreover, a universal and consensus definition of IOH may also facilitate the application of novel and emerging therapeutic interventions in treating IOH. We conducted a review to systematically record the reported definitions of intraoperative hypotension in adults undergoing non-cardiac surgery under general anaesthesia.

Methods

In accordance with Cochrane guidelines, we searched three online databases (OVID [Medline], Embase and Cochrane Library) for all studies published from 1 January 2000 to 6 September 2020. We evaluated the number of studies that reported the absolute or relative threshold values for defining blood pressure. Secondary aims included evaluation of the threshold values for defining IOH, the methodology for accounting for the severity of hypotension, whether the type of surgical procedure influenced the definition of IOH, and whether a study whose definition of IOH aligned with the Perioperative Quality Initiative-3 workgroup (POQI) consensus statement for defining was more likely to be associated with determining an adverse postoperative outcome.

Results

A total of 318 studies were included in the final qualitative synthesis. Most studies (n = 249; 78.3%) used an absolute threshold to define hypotension; 150 (60.5%) reported SBP, 117 (47.2%) reported MAP, and 12 (4.8%) reported diastolic blood pressure (DBP). 126 (39.6%) used a relative threshold to define hypotension. Of the included studies, 153 (48.1%) did not include any duration variable in their definition of hypotension. Among the selected 318 studies 148 (46.5%) studies defined IOH according to the POQI statement. When studies used a “relative blood pressure change” to define IOH, there was a weaker association in detecting adverse postoperative outcomes compared to studies who reported “absolute blood pressure change” (χ²(2) = 10.508, P = 0.005, Cramér’s V = 0.182). When studies used the POQI statement definition of hypotension or defined IOH by values higher than the POQI statement definition there were statistical differences observed between IOH and adverse postoperative outcomes (χ²(1) = 6.581, P = 0.037, Cramér’s V = 0.144). When both the duration of IOH or the numbers of hypotensive epochs were evaluated, we observed a significantly stronger relationship between the definition of IOH use the development of adverse postoperative outcomes. (χ²(1) = 4.860, P = 0.027, Cramér’s V = 0.124).

Conclusions

Most studies defined IOH by absolute or relative changes from baseline values. There are substantial inconsistencies in how IOH was reported. Further, definitions differed across different surgical specialities. Our findings further suggest that IOH should be defined using the absolute values stated in the POQI statement i.e., MAP < 60–70 mmHg or SBP < 100 mmHg. Finally, the number of hypotensive epochs or time-weighted duration of IOH should also be reported.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-022-01605-9.

Risk factors for postoperative delirium in patients with colorectal cancer

AIM

The purpose of this study was to identify the incidence of postoperative delirium in PCC (patients with colorectal cancer) and the related factors of postoperative delirium by analysing the differences in the general, disease-related and operation-related characteristics.

BACKGROUND

Previous studies had some limitations in generalising the risk factors for postoperative delirium in PCC due to the lack of relevant factors, such as disease- and operation-related characteristics. There is a need to investigate the factors of postoperative delirium by including cancer and surgical characteristics.

DESIGN

The current study is a cross-sectional study to investigate the correlated factors of postoperative delirium in PCC.

METHODS

A total of 196 patients who underwent colorectal cancer surgery at the Keimyung University Dongsan Hospital in Korea participated in the study. Data collection was performed from 15 August 2018 to 10 July 2019. Patients' general, disease-related and operation-related characteristics were collected from questionnaires and electronic medical records. Data analysis was performed using descriptive statistics, t test, Chi-square test and logistic regression using SPSS/WIN 22.0. The STROBE checklist has been used to report this study.

RESULTS

The results of this study showed that 26 (13.2%) PCC exhibited postoperative delirium and the risk factors for postoperative delirium were physical activity (OR = 2.94, p = .001), infection (OR = 2.17, p = .001) and nutritional status (OR = 1.10, p = .028).

CONCLUSION

To reduce and prevent the occurrence of postoperative delirium in PCC, encouraging participation in physical activity before and after surgery are required, and regular monitoring of the infection symptoms and nutritional status.

RELEVANCE TO CLINICAL PRACTICE

Based on the results of this study, postoperative delirium in PCC could be decreased by encouraging physical activity immediately following operation, monitoring the signs and symptoms of infection using diverse objective laboratory findings and maintaining the nutritional status within the normal range.

Comparison of restrictive fluid therapy with goal-directed fluid therapy for postoperative delirium in patients undergoing spine surgery: a randomized controlled trial

Background

Postoperative delirium (POD) is a common phenomenon after spinal surgery. Intraoperative fluid management may affect POD. The aim of this study was to compare the effects of restrictive fluid therapy (RF) with those of goal-directed fluid therapy (GDT) on POD.

Methods

A total of 195 patients aged ≥ 50 years who underwent spinal surgery were randomly divided into two groups: the RF group and the GDT group. In group RF, a bolus of lactated Ringer’s solution was administered at a dose of 5 mL·kg^-1 before the induction of anesthesia, followed by a dose of 5 mL·kg^-1·h^-1 until the end of surgery. For patients in the GDT group, in addition to the initial administration of lactated Ringer’s solution at 5 mL·kg^-1, the subsequent fluid therapy was adjusted by using a continuous noninvasive arterial pressure (CNAP) monitoring system to maintain pulse pressure variation (PPV) ≤ 14%. The primary endpoint was the incidence of POD, assessed once daily with the Confusion Assessment Method-Chinese Reversion (CAM-CR) scale at 1–3 days postoperatively. The secondary endpoints were intraoperative fluid infusion volume, urine volume, mean arterial pressure (MAP), heart rate (HR), cardiac index (CI), regional cerebral oxygen saturation (rSO₂) value, lactic acid value, and visual analog scale (VAS) pain score at 1–3 days after surgery. Moreover, postoperative complications and the length of hospital stay were recorded.

Results

The incidence of POD was lower in the GDT group than in the RF group (12.4% vs 4.1%; P = 0.035) in the first 3 days after spine surgery. Compared to group RF, group GDT exhibited a significantly increased volume of intraoperative lactated Ringer’s solution [1500 (interquartile range: 1128 to 1775) mL vs 1000 (interquartile range: 765 to 1300) mL, P < 0.001] and urine volume [398 (interquartile range: 288 to 600) mL vs 300 (interquartile range: 200 to 530) mL, P = 0.012]. Intraoperative MAP, CI and rSO₂ values were higher in the GDT group than in the RF group (P < 0.05). Moreover, the length of hospital stay [17.0 (14 to 20) days versus 14.5 (13 to 17.0) days, P = 0.001] was shorter in the GDT group than in the RF group.

Conclusions

GDT reduced the incidence of POD in middle- and old-aged patients undergoing spinal surgery possibly by stabilizing perioperative hemodynamic and improving the supply and demand of oxygen.

Trial registration

ChiCTR2000032603; Registered on May 3, 2020.

Grip strength as a predictor of postoperative delirium in patients with colorectal cancers

Background

The population is aging rapidly, and the population of patients who undergo surgeries is aging, too. Elderly patients have much risk of postoperative delirium, which increases the number of adverse events. The aim of this study was to investigate the risk factors of postoperative delirium in elderly patients with colorectal cancer.

Methods

We conducted a retrospective cohort analysis of consecutive patients aged 70 years and older who underwent surgeries for colorectal cancer at our department in the period from May 2012 to October 2019. We investigated the correlation between the incidence of postoperative delirium and Comprehensive Geriatric Assessment (CGA) scores, comorbidities, and perioperative factors. Postoperative delirium was retrospectively diagnosed by checking clinical records.

Results

Postoperative delirium was diagnosed in 36 of 271 patients (13.3%) with colorectal cancer. Among many comorbidities, only renal disease was significantly associated with postoperative delirium. Among the items in the CGA, age; Mini‐Mental State Exam (MMSE), Barthel Index, Instrumental Activities of Daily Living (IADL), Vitality Index, and Geriatric Depression Scale (GDS) scores; and grip strength were associated with postoperative delirium. Among perioperative factors, blood transfusion was associated with postoperative delirium. Multivariate logistic regression analysis identified older age, MMSE, GDS, and grip strength as significant independent risk factors for postoperative delirium.

Conclusions

This single‐center retrospective observational study demonstrated that grip strength is an independent predictor of postoperative delirium, along with age, MMSE, and GDS.

Intraoperative hypotension and delirium among older adults undergoing transcatheter aortic valve replacement

Background

Postoperative delirium (POD) is a frequently observed complication after transcatheter aortic valve replacement (TAVR). The effects of intraoperative hypotension (IOH) on POD occurrence are currently unclear.

Methods

A retrospective observational cohort study of patients who underwent TAVR was conducted. We predefined IOH as area under the threshold (AUT) of five mean arterial blood pressures (MBP), varying from <100 to <60 mmHg. The AUT consisted of the combination of duration and depth under the MBP thresholds, expressed in mmHg*min. All MBP AUTs were computed based on the complete procedure, independent of procedural phase or duration.

Results

This cohort included 675 patients who underwent TAVR under general anesthesia (n = 128, 19%) or procedural sedation (n = 547, 81%). Delirium occurred mostly during the first 2 days after TAVR, and was observed in n = 93 (14%) cases. Furthermore, 674, 672, 663, 630, and 518 patients had at least 1 min intraoperative MBP <100, <90, <80, <70, and <60 mmHg, respectively. Patients who developed POD had higher AUT based on all five MBP thresholds during TAVR. The penalized adjusted odds ratio varied between 1.08 (99% confidence interval [CI] 0.74–1.56) for the AUT based on MBP < 100 mmHg and OR 1.06 (99% CI 0.88–1.28) for the AUT based on MBP < 60 mmHg.

Conclusions

Intraoperative hypotension is frequently observed during TAVR, but not independently associated with POD after TAVR. Other potential factors than intraoperative hypotension may explain the occurrence of delirium after TAVR.

Target-Controlled Anesthesia Reduces Postoperative Delirium in Spinal Surgical Patients: A Prospective Pilot Study

The aim of this pilot study was to examine the effect of combined target-controlled anesthesia and manually controlled anesthesia on the incidence of postoperative delirium (POD) in patients undergoing spinal surgery. All of the patients were enrolled before spinal surgery and divided into 2 groups at random: one group received combined sevoflurane target-controlled inhalation and sufentanil target-controlled infusion (S-S TCI group), whereas the other received combined manually controlled sevoflurane inhalation and sufentanil infusion (S-S MCI group). Data related to preoperative factors, perioperative factors, and postoperative data were retrospectively collected. Compared with the S-S MCI group, the dosage of vasoactive drugs after surgery, postoperative recovery time, time to cannula removal, and the incidence of POD were significantly decreased in the S-S TCI group (P &lt; 0.05). Overall, POD appeared in 81 patients (16.8%) by postoperative day 3. Multiple regression analysis showed that postoperative blood loss and manually controlled anesthesia were risk factors for POD in spinal surgery patients. Therefore, prophylactic blood transfusion and phenylephrine can reduce the incidence of POD in the presence of postoperative hypotension. Target-controlled anesthesia may improve the quality of anesthesia as well as reduce POD in spinal surgical patients. These results provide clinical evidence for improving the prevention, diagnosis, and management of POD.

Intraoperative hypotension and its organ-related consequences in hypertensive subjects undergoing abdominal surgery: a cohort study

Purpose. Intraoperative hypotension is associated with organ hypoperfusion, which is deleterious to vital organs. Little is known about the prevalence and consequences of intraoperative hypotension in subjects with arterial hypertension (AH). The primary goal of this study was to investigate the prevalence and determinants of hypoperfusion-related clinical consequences of intraoperative hypotension, taking into account the role of AH, in a homogeneous cohort of patients undergoing abdominal surgery.Materials and methods. We enrolled 508 patients (219 males, median age 62 years). Intraoperative hypotension was defined as systolic blood pressure (SBP) <90 mmHg for at least 10 min or mean arterial pressure (MAP) <65 mmHg for at least 10 min or a need for noradrenaline infusion of at least 0.05 μg/kg/min for ≥10 min or intraoperative MAP drop of at least 30% from the baseline value for at least 10 min, regardless of the time of surgery. Acute kidney injury, stroke or transient ischaemic attack, delirium, and myocardial infarction were considered as the outcome.Results. AH concerned 234 (46%) individuals. The prevalence of intraoperative hypotension varied from 19.9 to 59.4%. Patients with AH were more likely to experience MAP drop of >30% than non-hypertensive patients (OR = 1.53; 95%CI 1.07-2.19; p = 0.02). The outcome was diagnosed in 38 (7.5%) patients. AH was a significant predictor of hypoperfusion-related events, regardless of the intraoperative hypotension definition applied (logOR 2.80 ÷ 3.22; p < 0.05 for all). Only intraoperative hypotension defined as 'MAP < 65mmHg' was found to be a determinant of negative outcome (logOR = 2.85; 95%CI 1.35-5.98; p < 0.01), with AUROC = 0.83 (95%CI 0.0-0.86); p < 0.01.Conclusion. AH is a significant predictor of hypoperfusion-related events, regardless of the intraoperative hypotension definition applied. In hypertensive patients, hypoperfusion-related clinical consequences are more frequent in high-risk and long-lasting procedures. MAP < 65 mmHg lasting for >10 min during surgery was identified as most associated with the negative outcome.

A clinical risk analysis of early post-operative delirium after laparoscopic colorectal cancer surgery in elderly patients: a retrospective study

PURPOSE

Early post-operative delirium (EPOD) is a frequent complication following colorectal surgery. The present study investigated the risk factors for EPOD after laparoscopic colorectal surgery in elderly patients.

METHODS

A retrospective study was conducted among 208 patients ≥70 years old who underwent laparoscopic colorectal surgery. Univariate and multivariate analyses were performed to determine the clinicopathological factors associated with the EPOD.

RESULTS

The overall incidence of EPOD was 10.1% (21/208). The univariate analysis showed that an older age (≥80 years old; P=0.002), sleeping pill medication before surgery (P=0.037), a history of dementia (P=0.030) and cerebrovascular disease (P=0.017), elevated levels of D-dimer (P=0.016), maximum intraoperative temperature ≥37 °C (P=0.036), and non-continuous usage of droperidol with analgesia (P=0.005) were associated with EPOD. The multivariate logistic regression analysis revealed an older age (≥80 years old; odds ratio [OR]: 6.26, 95% confidence interval [CI]: 1.94-20.15, P=0.002), sleeping pill medication before surgery (OR: 5.39, 95% CI: 1.36-21.28, P=0.016), history of cerebrovascular disease (OR: 3.91, 95% CI: 1.12-13.66, P=0.033), and maximum intraoperative temperature ≥37 °C (OR: 5.10, 95% CI: 1.53-16.92, P=0.008) to be independent risk factors. When the patients were divided into groups according to the number of positive risk factors, the prevalence rate was 6.5%, 16.0%, and 63.6% for patients with 1, 2, and 3 positive risk factors, respectively.

CONCLUSION

Our findings suggest that an older age, sleeping pill medication before surgery, history of cerebrovascular disease, and maximum intraoperative temperature ≥37 °C are independent risk factors of EPOD after laparoscopic colorectal surgery in elderly patients.

Association of intraoperative hypotension with postoperative morbidity and mortality: systematic review and meta-analysis

Background

Intraoperative hypotension, with varying definitions in literature, may be associated with postoperative complications. The aim of this meta-analysis was to assess the association of intraoperative hypotension with postoperative morbidity and mortality.

Methods

MEDLINE, Embase and Cochrane databases were searched for studies published between January 1990 and August 2018. The primary endpoints were postoperative overall morbidity and mortality. Secondary endpoints were postoperative cardiac outcomes, acute kidney injury, stroke, delirium, surgical outcomes and combined outcomes. Subgroup analyses, sensitivity analyses and a meta-regression were performed to test the robustness of the results and to explore heterogeneity.

Results

The search identified 2931 studies, of which 29 were included in the meta-analysis, consisting of 130 862 patients. Intraoperative hypotension was associated with an increased risk of morbidity (odds ratio (OR) 2.08, 95 per cent confidence interval 1.56 to 2.77) and mortality (OR 1.94, 1.32 to 2.84). In the secondary analyses, intraoperative hypotension was associated with cardiac complications (OR 2.44, 1.52 to 3.93) and acute kidney injury (OR 2.69, 1.31 to 5.55). Overall heterogeneity was high, with an I² value of 88 per cent. When hypotension severity, outcome severity and study population variables were added to the meta-regression, heterogeneity was reduced to 50 per cent.

Conclusion

Intraoperative hypotension during non-cardiac surgery is associated with postoperative cardiac and renal morbidity, and mortality. A universally accepted standard definition of hypotension would facilitate further research into this topic.

Investigating Association between Intraoperative Hypotension and Postoperative Neurocognitive Disorders in Non-Cardiac Surgery: A Comprehensive Review

Postoperative delirium (POD) and postoperative cognitive decline (deficit) (POCD) are related to a higher risk of postoperative complications and long-term disability. Pathophysiology of POD and POCD is complex, elusive and multifactorial. Intraoperative hypotension (IOH) constitutes a frequent and vital health hazard in the perioperative period. Unfortunately, there are no international recommendations in terms of diagnostics and treatment of neurocognitive complications which may arise from hypotension-related hypoperfusion. Therefore, we performed a comprehensive review of the literature evaluating the association between IOH and POD/POCD in the non-cardiac setting. We have concluded that available data are quite inconsistent and there is a paucity of high-quality evidence convincing that IOH is a risk factor for POD/POCD development. Considerable heterogeneity between studies is the major limitation to set up reliable recommendations regarding intraoperative blood pressure management to protect the brain against hypotension-related hypoperfusion. Further well-designed and effectively-performed research is needed to elucidate true impact of intraoperative blood pressure variations on postoperative cognitive functioning.

The correlation of intraoperative hypotension and postoperative cognitive impairment: a meta-analysis of randomized controlled trials

BACKGROUND

There is no consensus on whether intraoperative hypotension is associated with postoperative cognitive impairment. Hence, we performed a meta-analysis to evaluate the correlation of intraoperative hypotension and the incidence of postoperative delirium (POD) or postoperative cognitive dysfunction (POCD).

METHODS

We searched PubMed, Embase, and Cochrane Library databases to find randomized controlled trials (RCTs) in which reported the relationship between intraoperative hypotension and POD or POCD. The retrieval time is up to January 2020, without language restrictions. Quality assessment of the eligible studies was conducted by two researchers independently with the Cochrane evaluation system.

RESULTS

We analyzed five eligible RCTs. Based on the relative mean arterial pressure (MAP), participants were divided into low-target and high-target groups. For the incidence of POD, there were two studies with 99 participants in the low-target group and 94 participants in the high-target pressure group. For the incidence of POCD, there were four studies involved 360 participants in the low-target group and 341 participants in the high-target group, with a study assessed both POD and POCD. No significant difference between the low-target and the high-target group was observed in the incidence of POD (RR = 3.30, 95% CI 0.80 to 13.54, P = 0.10), or POCD (RR = 1.26, 95% CI 0.76 to 2.08, P = 0.37). Furthermore, it also demonstrates that intraoperative hypotension prolonged the length of ICU stay, but did not increased the mortality, the length of hospital stay, and mechanical ventilation (MV) time.

CONCLUSIONS

There is no significant correlation between intraoperative hypotension and the incidence of POD or POCD.

Assessment of Magnitude and Associated Factors of Emergence Delirium in the Post Anesthesia Care Unit at Tikur Anbesa Specialized Hospital, Ethiopia

Background

Emergence delirium (ED) is known as an acute agitation and confusion occurring during or immediately following emergence from general anesthesia, in the Operation Room or post anesthesia care unit (PACU). ED results in significant morbidity and complications resulting in longer hospital stays. We studied the magnitude and risk factors of ED in the general surgical population.

Methods

An institution-based prospective cross-sectional study was conducted on patients who underwent surgical procedure at Tikur Anbessa Specialized Hospital, Ethiopia, from March 6 – May 1, 2017. Data was collected using patient interview and chart review. Patients with Richmond Agitation Sedation Scale ≥+1 at any time were considered to have emergence delirium/agitation. Categorical data was analyzed using the fishers exact test. Continuous data was analyzed using student t-test. Independent variables were analyzed using binary logistic regression. P-value of <0.05 was considered as cutoff point to test for statistically significance.

Result

The overall magnitude of Emergence Delirium in this study was 31.7%. Older age (CI=4.266 – 12.095, P=0.001), substance abuse (OR =4.6, CI=1.962 – 10.863, P=0.001), preoperative anxiety (OR= 2.4, CI=1.140 – 5.244, P=0.02), benzodiazepine premedication (OR= 8, CI=2.788 – 23.21, P=0.001), excessive blood loss (OR=3.38, CI=1.789 – 6.412, P=0.001), postoperative pain (OR=3.37, CI=2.015 – 6.934, P=0.001) and longer PACU stay (CI=18.645 – 26.766, P=0.001) were positively associated with Emergence Delirium.

Conclusion

The magnitude of emergence delirium is high and it is associated with older age, substance abuse, premedication with benzodiazepine, excessive blood loss postoperative pain and longer PACU stay.

Risk factors for postoperative delirium after colorectal surgery: a systematic review and meta-analysis

PURPOSE

Postoperative delirium is common after any type of surgery and can lead to serious outcomes; thus, its prevention is important. Early assessment can help identify patients at higher risk of postoperative delirium. However, the risk factors for postoperative delirium in patients who underwent colorectal surgery are unclear. This meta-analysis aimed to identify the risk factors for postoperative delirium after colorectal cancer surgery.

METHODS

We selected all articles related to postoperative delirium after colorectal surgery published up to March 2019. Studies using any method for diagnosing delirium were eligible. Ovid-Embase, Ovid-Medline, and the Cochrane library were searched. Two reviewers independently conducted quality assessment and data collection. The risk factors identified in the studies were recorded, and a meta-analysis was conducted.

RESULTS

Of the 1216 studies initially screened, 1197 were reviewed by two independent reviewers. Finally, 14 articles were identified to be relevant for this review. In total, 11 of the 14 studies reported the risk factors for postoperative delirium. The incidence of postoperative delirium ranged from 8% to 54%. A total of 19 risk factors were identified, and we classified them into two categories as patient-related and treatment-related risk factors.

CONCLUSION

Postoperative delirium is highly common in those undergoing colorectal surgery including cancer, with advanced old age, history of preoperative delirium and preoperative serum albumin level which are risk factors for POD. Larger multi-institutional randomized studies to address this issue are warranted in the future.

Prevalence and risk factors for postoperative delirium in patients with colorectal carcinoma: a systematic review and meta-analysis

OBJECTIVE

Postoperative delirium (POD) is a common, but severe complication in elderly patients undergoing surgery for colorectal cancer, but the prevalence and potential risk factors for POD were not well established. Therefore, a meta-analysis was preformed to clarify the prevalence and risk factors of POD in patients undergoing surgery for colorectal cancer.

METHODS

PubMed, Embase, and the Cochrane Library were systematically searched on August 2019. Studies were included if they reported the prevalence and risk factors of POD in patients undergoing colorectal cancer surgery. The guidelines for critically appraising studies of prevalence or incidence of a health problem were used to assess the quality of included studies. Pooled odds ratios (ORs) for individual risk factors were estimated using the Mantel-Haenszel methods in random effect model. Sensitive analyses based on different inclusion criteria were conducted to explore whether the current meta-analysis was enough credible and robust.

RESULTS

Seventeen studies totaling 4472 patients undergoing colorectal cancer surgery were included. The pooled prevalence of POD is 14% (95% CI = 12-17%). Twelve significant risk factors were identified in pooled analysis including older age (OR = 1.10), sex (OR = 1.87), history of psychiatric disease (OR = 6.47), comorbidities (OR = 2.17), prognostic nutritional index (OR = 1.12), physical status (OR = 1.27), American Society of Anesthesiologists Score (ASA Scores) (OR = 1.65), history of alcohol abuse (OR = 2.23), postoperative pain management (OR = 1.91), perioperative blood transfusion (OR = 2.37), cognitive status (OR = 1.91), and lower serum level of albumin (OR = 0.58).

CONCLUSIONS

POD is a frequent complication in patients undergoing surgery with colorectal cancer. Several risk factors including history of psychiatric disease, transfusion, comorbidities, male gender, and old age were significant predictors for POD.

Risk Factors and Incidence of Postoperative Delirium in Patients Undergoing Laryngectomy

OBJECTIVE

To explore the risk factors and incidence of postoperative delirium (POD) in patients undergoing laryngectomy for laryngeal cancer.

STUDY DESIGN

Prospective cohort study.

SETTING

Shanghai Eye, Ear, Nose, and Throat Hospital, Fudan University.

SUBJECTS AND METHODS

A total of 323 patients underwent laryngectomy from April 4, 2018, to December 28, 2018. Perioperative data were collected. The primary outcome was the presence of POD as defined by the Confusion Assessment Method diagnostic algorithm. Univariate and multivariable logistic regression analyses were used to identify risk factors associated with POD.

RESULTS

Of the patients who underwent laryngectomy during the study period, 99.1% were male, with a mean age of 60.0 years. Of these patients, 28 developed POD, with most episodes (88.1%) occurring during the first 3 postoperative days. The type of POD was hyperactive in 7 cases and hypoactive in 21 cases. The mean duration of POD was 1 day. The mean Delirium Rating Scale-Revised-98 score (a measure of POD severity) was 11.5. For the multivariable analysis, risk factors associated with POD included advanced cancer stage, lower educational level, higher American Society of Anesthesiologists classification, and intraoperative hypotension lasting at least 30 minutes. Intraoperative dexmedetomidine use was protective against POD.

CONCLUSION

This study identified risk factors associated with POD, providing a target population for quality improvement initiatives. Furthermore, intraoperative dexmedetomidine use can reduce POD.

Pre-operative biomarkers and imaging tests as predictors of post-operative delirium in non-cardiac surgical patients: a systematic review

Background

Post-operative delirium (POD) is a common post-operative complication in elderly individuals and imposes a significant health and financial burden. Identifying predictive biomarkers may help understand the pathophysiology of POD. Our objective is to summarize the evidence of pre-operative biomarkers and imaging tests to predict POD in patients undergoing non-cardiac surgery.

Methods

A systematic search of English language articles in MEDLINE, EMBASE, Cochrane Database, PsychINFO, PubMed and ClinicalTrials. Gov up to January 2018 was performed. Studies that used biomarkers or imaging tests to predict POD and a validated POD assessment tool were included. Animal studies, paediatric, cardiac and intracranial surgery were excluded. Risk of bias was assessed using the Quality In Prognosis Study tool.

Results

Thirty-four prospective cohort studies involving 4424 patients were included. Nineteen studies described serum tests [Interleukin-6, Insulin-like Growth Factor 1, C-Reactive Protein (CRP), cholinesterases, apolipoprotein-E genotype, leptin, hypovitaminosis, hypoalbuminaemia, gamma-amino butyric acid], 10 described cerebral-spinal fluid tests (monoamine precursor, melatonin, acute phase proteins, S100B and neurofibrillary tangles), and 5 described imaging tests. Two studies had high risk of bias due to unclear outcome measurement and study participation. CRP was significantly associated with POD in 5 studies. Other biomarkers were either examined by only a single study or two or more studies with conflicting results.

Conclusion

CRP is the most promising biomarker associated with POD. However, we are still in the early stages in identifying biomarkers and imaging tests that may further understanding of the pathophysiology of POD.

Electronic supplementary material

The online version of this article (10.1186/s12871-019-0693-y) contains supplementary material, which is available to authorized users.

A daily multidisciplinary assessment of older adults undergoing elective colorectal cancer surgery is associated with reduced delirium and geriatric syndromes

OBJECTIVES

Comprehensive geriatric assessment (CGA) has shown to benefit older patients undergoing urological and orthopedic surgery. However, this approach has been scarcely assessed in patients elected for colorectal surgery.

MATERIALS AND METHODS

Retrospective cohort of patients aged ≥70 years admitted for elective colorectal cancer surgery to a single hospital between 2008 and 2012. Upon admission, patients were assigned to a usual care (UC) plan or a CGA-based care (GS) plan conducted by a multidisciplinary team, according to standard clinical criteria.Analyzed outcomes included the incidence of delirium and other geriatric syndromes during hospital stay, mortality, readmissions, andnumber of perioperative complications.

RESULTS

The cohort included 310 patients, 203 assigned to the GS group and 107 to the UC group. Patients in the GS group had significantly lower Barthel and Lawton scores, higher prevalence of dementia and heart failure, and higher comorbidity burden. Fifty-four (17.5%) patientsexperienced delirium (23 [11.3%] and 31 [29.2%] in the GS and UC groups, respectively; p < .001), and 49 (15.8%) patient experienced other geriatric syndromes (21 [10.3%] and 28 [26.2%] in the GS and UC groups, respectively; p < .001). Serious complications were more frequent in the GS group: 154 (75.9%) vs 60 (56.1%) in the UC group; p < .001. No significant differences were observed between groups regarding readmissions, and in-hospital and post-discharge (1 year follow-up) mortality.

CONCLUSIONS

Despite the poorer clinical condition of patients in the GS group, the CGA-based intervention resulted in a lower incidence of delirium and other geriatric syndromes compared with the UC group.

Delirium After Cardiac Surgery and Cumulative Fluid Balance: A Case-Control Cohort Study

OBJECTIVE

To assess a novel hypothesis to explain delirium after cardiac surgery through the relationship between cumulative fluid balance and delirium. This hypothesis involved an inflammatory process combined with a hypervolemic state, which could lead to venous congestion reaching the brain.

DESIGN

Retrospective case-control (1:1) cohort study.

SETTING

University-affiliated tertiary cardiology center.

PARTICIPANTS

Cardiac surgery intensive care unit (ICU) patients.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Cumulative fluid balance was evaluated at 3 times: (1) upon arrival at the ICU after surgery, (2) 24 hours post-ICU arrival, and (3) 48 hours post-ICU arrival. A generalized estimated equation was used to model the association between cumulative fluid balance and delirium occurrence 24 hours later. Covariates were selected based on the statistical differences between cases and controls on delirium risk factors and clinical characteristics. The cohort included 346 patients, of which 39 (11%), 104 (30%), and 142 patients (41%) presented delirium at 24, 48, and 72 hours post-ICU arrival, respectively. The effect of time had an odds ratio (OR) of 2.14, 95% confidence interval (CI) 1.603 to 2.851, and a p value < 0.001. The cumulative fluid balance was associated with delirium occurrence (OR 1.20, 95% CI: 1.066-1.355, p = .003). History of neurological disorder, having both hearing and visual impairment, type of procedure, perioperative cerebral oximetry, mean pulmonary artery pressure pre-cardiopulmonary bypass (CPB), and mean arterial pressure post-CPB also contributed to delirium in the model.

CONCLUSION

Delirium is associated with a cumulative fluid balance, but the extent through which this plays an etiologic role remains to be determined.

Intraoperative hypotension and the risk of postoperative adverse outcomes: a systematic review

BACKGROUND

Intraoperative hypotension is a common side effect of general anaesthesia and might lead to inadequate organ perfusion. It is unclear to what extent hypotension during noncardiac surgery is associated with unfavourable outcomes.

METHODS

We conducted a systematic search in PubMed, Embase, Web of Science, and CINAHL, and classified the quality of retrieved articles according to predefined adapted STROBE and CONSORT criteria. Reported strengths of associations from high-quality studies were classified into end-organ specific injury risks, such as acute kidney injury, myocardial injury, and stroke, and overall organ injury risks for various arterial blood pressure thresholds.

RESULTS

We present an overview of 42 articles on reported associations between various absolute and relative intraoperative hypotension definitions and their associations with postoperative adverse outcomes after noncardiac surgery. Elevated risks of end-organ injury were reported for prolonged exposure (≥10 min) to mean arterial pressures <80 mm Hg and for shorter durations <70 mm Hg. Reported risks increase with increased durations for mean arterial pressures <65-60 mm Hg or for any exposure <55-50 mm Hg.

CONCLUSIONS

The reported associations suggest that organ injury might occur when mean arterial pressure decreases <80 mm Hg for ≥10 min, and that this risk increases with blood pressures becoming progressively lower. Given the retrospective observational design of the studies reviewed, reflected by large variability in patient characteristics, hypotension definitions and outcomes, solid conclusions on which blood pressures under which circumstances are truly too low cannot be drawn. We provide recommendations for the design of future studies. CLINICAL REGISTRATION NUMBER: (PROSPERO ID). CRD42013005171.

Perioperative myocardial injury and the contribution of hypotension

Mortality in the month following surgery is about 1000 times greater than anesthesia-related intraoperative mortality, and myocardial injury appears to be the leading cause. There is currently no known safe prophylaxis for postoperative myocardial injury, but there are strong associations among hypotension and myocardial injury, renal injury, and death. During surgery, the harm threshold is a mean arterial pressure of about 65 mmHg. In critical care units, the threshold appears to be considerably greater, perhaps 90 mmHg. The threshold triggering injury on surgical wards remains unclear but may be in between. Much of the association between hypotension and serious complications surely results from residual confounding, but sparse randomized data suggest that at least some harm can be prevented by intervening to limit hypotension. Reducing hypotension may therefore improve perioperative outcomes.

Postoperative delirium in elderly patients with critical limb ischemia undergoing major leg amputation: a retrospective study

BACKGROUND

Critical limb ischemia has been identified as a risk factor for the incidence of postoperative delirium in elderly patients. Limb amputation is the last option in critical limb ischemia treatments. We investigated the incidence and predisposing factors of postoperative delirium in patients undergoing major leg amputation.

METHODS

From January 2012 to December 2016, 121 patients aged over 60 years who had undergone major leg amputation were enrolled in this study. Various factors related to the patients' outcomes were assessed, including demographic, preoperative laboratory, anesthetic, surgical, and postoperative indicators.

RESULTS

Twenty two patients were excluded and 99 patients were assigned to either the delirium group or no delirium group. Forty of them (40%) developed a delirium during 30 days postoperatively. Univariate analysis implied that end-stage renal disease on hemodialysis, alcohol consumption, C-reactive protein, staying in an intensive care unit (ICU), duration of an ICU stay, occurrence of complications, and mortality during six months, were the factors that accounted for significant differences between the two groups. In multivariate analysis, three factors were significantly related to the development of delirium: mortality during six months (odds ratio [OR] = 13.86, 95% CI [2.10-31.90]), alcohol (OR = 8.18, 95% CI [1.13-16.60]), and hemodialysis (OR = 4.34, 95% CI [2.06-93.08]).

CONCLUSIONS

Approximately 40% of the elderly patients suffered from postoperative delirium in major leg amputation. Identifying those with risk factors for postoperative delirium and intervening at the early stage will be of great benefit in major leg amputations for the elderly population.

Identifying Older Adults at Risk of Delirium Following Elective Surgery: A Systematic Review and Meta-Analysis

BACKGROUND

Postoperative delirium is a common preventable complication experienced by older adults undergoing elective surgery. In this systematic review and meta-analysis, we identified prognostic factors associated with the risk of postoperative delirium among older adults undergoing elective surgery.

METHODS

Medline, EMBASE, CINAHL, Cochrane Central Register of Controlled Trials, and AgeLine were searched for articles published between inception and April 21, 2016. A total of 5692 titles and abstracts were screened in duplicate for possible inclusion. Studies using any method for diagnosing delirium were eligible. Two reviewers independently completed all data extraction and quality assessments using the Cochrane Risk-of-Bias Tool for randomized controlled trials (RCTs) and the Newcastle-Ottawa Scale (NOS) for cohort studies. Random effects meta-analysis models were used to derive pooled effect estimates.

RESULTS

Forty-one studies (9384 patients) reported delirium-related prognostic factors. Among our included studies, the pooled incidence of postoperative delirium was 18.4% (95% confidence interval [CI] 14.3-23.3%, number needed to follow [NNF] = 6). Geriatric syndromes were important predictors of delirium, namely history of delirium (odds ratio [OR] 6.4, 95% CI 2.2-17.9), frailty (OR 4.1, 95% CI 1.4-11.7), cognitive impairment (OR 2.7, 95% CI 1.9-3.8), impairment in activities of daily living (ADLs; OR 2.1, 95% CI 1.6-2.6), and impairment in instrumental activities of daily living (IADLs; OR 1.9, 95% CI 1.3-2.8). Potentially modifiable prognostic factors such as psychotropic medication use (OR 2.3, 95% CI 1.4-3.6) and smoking status (OR 1.8 95% CI 1.3-2.4) were also identified. Caregiver support was associated with lower odds of postoperative delirium (OR 0.69, 95% CI 0.52-0.91).

DISCUSSION

Though caution must be used in interpreting meta-analyses of non-randomized studies due to the potential influence of unmeasured confounding, we identified potentially modifiable prognostic factors including frailty and psychotropic medication use that should be targeted to optimize care.

Impact of timing and duration of postoperative delirium: a retrospective observational study

BACKGROUND

Recent reports suggest that not all critically ill patients with delirium share the same consequences. The outcomes of surgical intensive care unit patients with postoperative delirium were evaluated depending on the onset and duration of delirium.

METHODS

A total of 527 patients who were admitted from the operating theater and cared for in the surgical intensive care unit for >24 hours were evaluated for delirium using the Confusion Assessment Method for intensive care unit, 3 times a day. Patients were analyzed according to the onset time and duration of delirium. Patients were classified into 4 groups according to the onset and duration of delirium: no delirium, early brief delirium (delirium for <1 day on postoperative day 0), late brief delirium (delirium for <1 day after postoperative day 0), and persistent delirium (delirium for ≥1 days). Duration of stay (intensive care unit and hospital) and mortality (intensive care unit, hospital, and 1-year) were outcomes of interest.

RESULTS

Of the 527 patients, delirium developed in 119 (22.6%) patients. More than two-thirds of the patients developed delirium on postoperative day 0 or 1, and 70% of patients developed delirium for >24 hours (persistent). Persistent delirium was associated with longer intensive care unit (4.6 [1.1-53.3] vs 1.6 [1.1-37.5] days) and hospital duration of stay (24 [3-112] vs 16 [2-225] days) and higher hospital mortality (14.5% vs 2.2%) compared to no delirium (P < .01).

CONCLUSION

For postoperative intensive care unit patients, intensive care unit and hospital duration of stay did not seem to differ between patients with early brief delirium or no delirium, whereas patients with late brief or persistent delirium seemed to show longer intensive care unit and hospital duration of stay and higher mortality.

Postoperative Delirium in Indian Patients Following Major Abdominal Surgery for Cancer: Risk Factors and Associations

Postoperative delirium (POD) is not uncommon following major abdominal surgery with its incidence ranging between five and 51%. As cancer affects disproportionately, the population older than 65 years and as delirium is more common in the elderly, surgical oncology patients are at a higher risk of developing POD. The present study was undertaken to explore the impact and associations of POD in Indian patients undergoing oncological major abdominal surgery. A retrospective review of the electronic medical records in a tertiary cancer care institution of all postoperative patients who had undergone major gastrointestinal gynaecological and urological abdominal surgery for cancer and required psycho-oncology referral was performed. Patient, surgery and postoperative outcome-related data were collected. Statistical analysis was performed using univariate and multivariate logistic regression analysis. Out of 824 patients who underwent major abdominal surgery, 33 patients (4.0%) were diagnosed with POD. In univariate analysis, older age and history of addiction were found to be statistically significantly associated with POD (p < 0.001). Among the postoperative factors, respiratory complications (p < 0.001), sepsis (p < 0.05), ICU stay > 24 h (p < 0.05) and electrolyte impairment (p < 0.05) were the significant associations with the POD. Thirty-day mortality was higher in the POD group (p < 0.05). In multivariate logistic regression analysis, advanced age, addictions, respiratory complications and sepsis were found to be significant associations with POD, p < 0.001. Postoperative delirium is associated with higher mortality. Older age, postoperative respiratory complications and sepsis are common contributory factors of postoperative delirium.

Preoperative severe hypoalbuminemia is associated with an increased risk of postoperative delirium in elderly patients: Results of a secondary analysis

PURPOSE

To explore the association between the severity of preoperative hypoalbuminemia and the occurrence of postoperative delirium.

MATERIALS AND METHODS

This was a secondary analysis of the database from a previously conducted clinical trial. 700 elderly patients (age ≥65years) who were admitted to intensive care unit (ICU) after noncardiac surgery were included. Delirium was assessed with the Confusion Assessment Method for the ICU twice daily during the first 7days postoperatively. Other outcomes were also monitored. The relationship between preoperative albumin level and postoperative delirium were analyzed using a logistic regression model.

RESULTS

111 of 700 patients (15.9%) developed postoperative delirium. When compared with normal albumin level (>40.0g/L), severe (≤30.0g/L: OR 2.727, 95% CI 1.283-5.797, P=0.009), but not mild (35.1-40.0g/L: OR 1.175, 95% CI 0.679-2.032, P=0.565) or moderate (30.1-35.0g/L: OR 1.674, 95% CI 0.897-3.122, P=0.105) hypoalbuminemia was associated with an increased risk of postoperative delirium. Preoperative severe hypoalbuminemia was also associated with prolonged mechanical ventilation, increased non-delirium complications, and prolonged ICU and hospital stay after surgery.

CONCLUSIONS

Preoperative severe hypoalbuminemia (≤30.0g/L) was associated with an increased risk of postoperative delirium and worse outcomes.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, www.chictr.org.cn, ChiCTR-TRC-10000802.

Perioperative hemodynamics and risk for delirium and new onset dementia in hip fracture patients; A prospective follow-up study

BACKGROUND

Delirium is common in hip fracture patients and many risk factors have been identified. Controversy exists regarding the possible impact of intraoperative control of blood pressure upon acute (delirium) and long term (dementia) cognitive decline. We explored possible associations between perioperative hemodynamic changes, use of vasopressor drugs, risk of delirium and risk of new-onset dementia.

METHODS

Prospective follow-up study of 696 hip fracture patients, assessed for delirium pre- and postoperatively, using the Confusion Assessment Method. Pre-fracture cognitive function was assessed using the Informant Questionnaire of Cognitive Decline in the Elderly and by consensus diagnosis. The presence of new-onset dementia was determined at follow-up evaluation at six or twelve months after surgery. Blood pressure was recorded at admission, perioperatively and postoperatively.

RESULTS

Preoperative delirium was present in 149 of 536 (28%) assessable patients, and 124 of 387 (32%) developed delirium postoperatively (incident delirium). The following risk factors for incident delirium in patients without pre-fracture cognitive impairment were identified: low body mass index, low level of functioning, severity of physical illness, and receipt of ≥ 2 blood transfusions. New-onset dementia was diagnosed at follow-up in 26 of 213 (12%) patients, associated with severity of physical illness, delirium, receipt of vasopressor drugs perioperatively and high mean arterial pressure postoperatively.

CONCLUSION

Risk factors for incident delirium seem to differ according to pre-fracture cognitive status. The use of vasopressors during surgery and/or postoperative hypertension is associated with new-onset dementia after hip fracture.

Risk factors for postoperative delirium after colorectal operation

BACKGROUND

A clear understanding of risk factors for postoperative delirium helps in the selection of individuals who might benefit from targeted perioperative intervention. The aim of this study was to identify risk factors for postoperative delirium after colorectal operation for malignancy.

METHODS

All consecutive patients who underwent elective or emergency operation because of malignancy of the colon, sigmoid, or rectum between 2009 and 2012 were included in this study. Potential risk factors for postoperative delirium were selected based on previous studies. These candidate factors were analyzed using univariate and multivariate logistic regression analysis. Based on this analysis, odds ratios and 95% confidence intervals were estimated.

RESULTS

A total of 436 patients underwent an oncologic resection of the colon, sigmoid, or rectum. Postoperative delirium was observed in 45 (10.3%) patients. Patients with a delirium had a greater in-hospital mortality rate (8.9% vs 3.6%, P = .09), spent more days in the intensive care unit, and had a longer total hospital stay. Variables associated with postoperative delirium in univariate analyses were age, American Society of Anesthesiologists classification, blood transfusion, history of psychiatric disease, history of cerebrovascular disease, postoperative pain management, postoperative renal impairment, C-reactive protein levels, leukocyte blood count, and postoperative complications. Independent risk factors were history of psychiatric disease (odds ratio 8.38, 95% confidence interval: 1.50-46.82), age (odds ratio 4.01, 95% confidence interval; 1.55-10.37), and perioperative blood transfusion (odds ratio 2.37, 95% confidence interval; 1.11-5.06).

CONCLUSION

This study shows that postoperative delirium is a frequently encountered complication after colorectal operation. Three independent risk factors for postoperative delirium were identified (history of psychiatric disease, age, and perioperative transfusion) that may contribute to risk estimation in this patient population.

Comparative Study of Delirium in Emergency and Consultation Liaison- A Tertiary Care Hospital Based Study in Northern India

INTRODUCTION

Delirium is an acute and often fluctuating disturbance in level of consciousness and thought process (cognition) that develops over a short period of time and is a significant change from previous level of functioning. Its prevalence increases with age, complexity of medical co- morbidities and number of medications prescribed.

AIM

To compare the cause and severity of delirium in patients in emergency and consultation liaison psychiatry group.

MATERIALS AND METHODS

A cross-sectional, tertiary care hospital based study was conducted on the patients who presented with delirium from emergency department (50) and consultation-liaison psychiatry groups (50), over a period of one year. The diagnosis was made on the basis of DSM- 5 criteria. The Delirium Rating Scale (DRS-R-98) was applied to know the severity of delirium, cognitive and non-cognitive symptoms of delirium in patients. The results were subjected to appropriate statistical analysis.

RESULTS

In emergency group, 42% patients had metabolic abnormalities, while in consultation-liaison, 38% patients had hyponatremia and hypokalemia and the difference was found to be statistically non-significant (p>0.05). In emergency group, 21(42%) patients were diagnosed as delirium due to other medical condition, followed by 13 (26%) and 8(16%) patients, who were diagnosed as delirium due to multiple aetiologies and substance intoxication each respectively. In only 33(66%) cases in consultation liaison group patients had delirium secondary to other medical conditions. As per DRS-R98 Scale, mean severity score was found to be statistically significant (p<0.05) in consultation liaison group as compared to emergency department group (p> 0.05).

CONCLUSION

Delirium is multifactorial aetiological disease, with variable but preventable outcome. Approach should be aimed at finding the treatable causes to reduce morbidity and mortality.

Systematic review and meta-analysis of risk factors for postoperative delirium among older patients undergoing gastrointestinal surgery

BACKGROUND

Postoperative delirium (POD) is common after surgery. As age is a known risk factor, the increased ageing of the population undergoing surgery emphasizes the importance of the subject. Knowledge of other potential risk factors in older patients with surgical gastrointestinal diseases is lacking. The aim here was to collate and synthesize the published literature on risk factors for delirium in this group.

METHODS

Five databases were searched (MEDLINE, Web of Science, Embase, CINAHL(®) and PSYCinfo(®) ) between January 1987 and November 2014. The Newcastle-Ottawa Scale was used to rate study quality. Pooled odds ratios or mean differences for individual risk factors were estimated using the Mantel-Haenszel and inverse-variance methods.

RESULTS

Eleven studies met the inclusion criteria; they provided a total of 1427 patients (318 with delirium and 1109 without), and predominantly included patients undergoing elective colorectal surgery. The incidence of POD ranged from 8·2 to 54·4 per cent. A total of 95 risk factors were investigated, illustrating wide heterogeneity in study design. Seven statistically significant risk factors were identified in pooled analysis: old age, American Society of Anesthesiologists (ASA) physical status grade at least III, body mass index, lower serum level of albumin, intraoperative hypotension, perioperative blood transfusion and history of alcohol excess. Patients with POD had a significantly increased duration of hospital stay and a higher mortality rate compared with those without delirium.

CONCLUSION

Delirium is common in older patients undergoing gastrointestinal surgery. Several risk factors were consistently associated with POD.

New aspects of delirium in elderly patients with critical limb ischemia

Objective

The primary objective was to identify possible risk factors for delirium in patients with critical limb ischemia undergoing surgery. The secondary objective was to study the effect of delirium on complications, the length of hospital stay, health care costs, and mortality.

Methods

All patients 65 years or older with critical limb ischemia undergoing surgery from February 2013 to July 2014 at Amphia Hospital, were included and followed up until December 31, 2014. Delirium was scored using the Delirium Observation Screening Scale (DOSS). Perioperative risk factors (age, comorbidity, factors of frailty, operation type, hemoglobulin, and transfusion) were collected and analyzed using logistic regression. Secondary outcomes were the number of complications, total hospital stay, extra health care costs per delirium, and mortality within 3 months and 6 months of surgery.

Results

We included 92 patients with critical limb ischemia undergoing surgery. Twenty-nine (32%) patients developed a delirium during admission, of whom 17 (59%) developed delirium preoperatively. After multivariable analysis, only diabetes mellitus (odds ratio [OR] =6.23; 95% confidence interval [CI]: 1.11–52.2; P=0.035) and Short Nutritional Assessment Questionnaire for Residential Care (SNAQ-RC) ≥3 (OR =5.55; 95% CI: 1.07–42.0; P=0.039) was significantly associated with the onset of delirium. Delirium was associated with longer hospital stay (P=0.001), increased health care costs, and higher mortality after 6 months (P<0.001).

Conclusion

Delirium is a common adverse event in patients with critical limb ischemia undergoing surgery with devastating outcome in the long term. Most patients developed delirium preoperatively, which indicates the need for early recognition and preventive strategies in the preoperative period. This study identified undernourishment and diabetes mellitus as independent risk factors for delirium.

Risk Factors and Outcomes for Postoperative Delirium after Major Surgery in Elderly Patients

Background

Early identification of patients at risk for delirium is important, since adequate well timed interventions could prevent occurrence of delirium and related detrimental outcomes. The aim of this study is to evaluate prognostic factors for delirium, including factors describing frailty, in elderly patients undergoing major surgery.

Methods

We included patients of 65 years and older, who underwent elective surgery from March 2013 to November 2014. Patients had surgery for Abdominal Aortic Aneurysm (AAA) or colorectal cancer. Delirium was scored prospectively using the Delirium Observation Screening Scale. Pre- and peri-operative predictors of delirium were analyzed using regression analysis. Outcomes after delirium included adverse events, length of hospital stay, discharge destination and mortality.

Results

We included 232 patients. 51 (22%) underwent surgery for AAA and 181 (78%) for colorectal cancer. Postoperative delirium occurred in 35 patients (15%).

Predictors of postoperative delirium included: delirium in medical history (Odds Ratio 12 [95% Confidence Interval 2.7–50]), advancing age (Odds Ratio 2.0 [95% Confidence Interval 1.1–3.8]) per 10 years, and ASA-score ≥3 (Odds Ratio 2.6 [95% Confidence Interval 1.1–5.9]). Occurrence of delirium was related to an increase in adverse events, length of hospital stay and mortality.

Conclusion

Postoperative delirium is a frequent complication after major surgery in elderly patients and is related to an increase in adverse events, length of hospital stay, and mortality. A delirium in the medical history, advanced age, and ASA-score may assist in defining patients at increased risk for delirium. Further attention to prevention of delirium is essential in elderly patients undergoing major surgery.

Intraoperative hypotension and delirium after on-pump cardiac surgery

BACKGROUND

Delirium is a common complication after cardiac surgery and may be as a result of inadequate cerebral perfusion. We studied delirium after cardiac surgery in relation to intraoperative hypotension (IOH).

METHODS

This observational single-centre, cohort study was nested in a randomized trial, on a single intraoperative dose of dexamethasone vs placebo during cardiac surgery. During the first four postoperative days, patients were screened for delirium based on the Confusion Assessment Method (CAM) for Intensive Care Unit on the intensive care unit, CAM on the ward, and by inspection of medical records. To combine depth and duration of IOH, we computed the area under the curve for four blood pressure thresholds. Logistic regression analyses were performed to investigate the association between IOH and the occurrence of postoperative delirium, adjusting for confounding and using a 99% confidence interval to correct for multiple testing.

RESULTS

Of the 734 included patients, 99 patients (13%) developed postoperative delirium. The adjusted Odds Ratio for the Mean Arterial Pressure <60 mm Hg threshold was 1.04 (99% confidence interval: 0.99-1.10) for each 1000 mm Hg(2) min(2) AUC(2) increase. IOH, as defined according to the other three definitions, was not associated with postoperative delirium either. Deep and prolonged IOH seemed to increase the risk of delirium, but this was not statistically significant.

CONCLUSIONS

Independent of the applied definition, IOH was not associated with the occurrence of delirium after cardiac surgery.

Association between intraoperative blood pressure and postoperative delirium in elderly hip fracture patients

Background

One possible area of intervention to prevent postoperative delirium (PD) is intraoperative blood pressure management. However, the relationship between intraoperative blood pressure and PD is unclear. A secondary analysis of a RCT study examining the PD risk over the range of absolute intraoperative mean arterial blood pressure (MAP) readings and the corresponding relative changes from preoperative baseline level was performed to determine the role of MAP on PD.

Methods

Nonparametric locally weighted quadratic polynomial smoothing (LOESS) regression explored the pattern of PD risk at postoperative day 2 as a function of mean surgery MAP (msMAP) and percent change of msMAP from baseline in 103 elderly hip fracture patients. Segment-linear logistic regression models were then constructed to determine the odds ratios (OR) of PD over the observed range of these msMAP measures, adjusting for potential confounds.

Results

Twenty-three patients (22%) developed PD on day 2. LOESS regression revealed a j-shaped association between absolute levels of msMAP and PD risk. When msMAP was ≥80 mmHg, higher msMAP imparted greater PD risk (OR = 2.28 per 10 mmHg msMAP increase; 95% CI: 1.11–4.70), while higher msMAP was associated with lower PD risk (OR = 0.19 per 10 mmHg increase; CI: 0.05–0.76) if msMAP was <80 mmHg. There was no statistically significant relationship between PD risk and average percent change from baseline in these msMAP measures.

Conclusion

In elderly hip fracture patients, both very high and very low levels of msMAP were associated with significantly increased risk of PD.