A prospective,observational study of cerebrovascular autoregulation and its association with delirium following cardiac surgery

This aim of this prospective observational cohort study was to evaluate any association between postoperatively impaired cerebrovascular autoregulation and the onset of delirium following cardiac surgery. Previous studies have shown that impaired intra-operative cerebrovascular autoregulation during cardiopulmonary bypass is associated with delirium. However, postoperative changes in cerebrovascular autoregulation and its association with delirium have not been investigated. One-hundred and eight consecutive adult cardiac surgical patients without baseline cognitive dysfunction or aphasia were included in the study. Cerebrovascular autoregulation was assessed by the Pearson correlation between near-infrared spectroscopy-derived cerebral tissue oxygen saturation and mean arterial pressure to derive the tissue oximetry index. Cerebrovascular autoregulation was monitored for a minimum of 90 min on postoperative day 0 and postoperative day 1. Delirium was assessed throughout intensive care unit admission using the confusion assessment method for the intensive care unit. We observed delirium in 24 of the 108 patients studied. The mean (SD) tissue oximetry index was higher in delirious patients on postoperative day 0 compared with non-delirious patients; 0.270 (0.199) vs. 0.180 (0.142), p = 0.044, but not on postoperative day 1; 0.130 (0.160) vs. 0.150 (0.130), p = 0.543. All patients showed improvement in tissue oximetry index on postoperative day 1 compared with postoperative day 0. Logistic regression analysis demonstrated tissue oximetry index on postoperative day 0 to be independently associated with delirium; odds ratio 1.05 (95%CI 1.01–1.10), p = 0.043. In conclusion, we found an association between impaired cerebrovascular autoregulation, measured by near-infrared spectroscopy, and delirium in the early postoperative period.     

A randomised controlled trial of dexmedetomidine for delirium in adults undergoing heart valve surgery

Dexmedetomidine might reduce delirium after cardiac surgery. We allocated 326 participants to an infusion of dexmedetomidine at a rate of 0.6 μg kg⁻¹ for 10 min and then at 0.4 μg.kg⁻¹.h⁻¹ until the end of surgery; 326 control participants received comparable volumes of saline. We detected delirium in 98/652 (15%) participants during the first seven postoperative days: 47/326 after dexmedetomidine vs. 51/326 after placebo, p = 0.62, adjusted relative risk (95%CI) 0.86 (0.56–1.33), p = 0.51. Postoperative renal impairment (Kidney Disease Improving Global Outcomes stages 1, 2 and 3) was detected in 46, 9 and 2 participants after dexmedetomidine and 25, 7 and 4 control participants, p = 0.040. Intra-operative dexmedetomidine infusion did not reduce the incidence of delirium after cardiac valve surgery but might impair renal function.     

Dexmedetomidine for adult cardiac surgery: a systematic review,meta-analysis and trial sequential analysis

The effects of dexmedetomidine in adults undergoing cardiac surgery are inconsistent. We conducted a systematic review and meta-analysis to analyse the effects of peri-operative dexmedetomidine in adults undergoing cardiac surgery. We searched MEDLINE via Pubmed, EMBASE, Scopus and Cochrane for relevant randomised controlled trials between 1 January 1990 and 1 March 2022. We used the Joanna Briggs Institute methodology checklist to assess study quality and the GRADE approach to certainty of evidence. We assessed the sensitivity of results to false data. We used random-effects meta-analyses to analyse the primary outcomes: durations of intensive care and tracheal intubation. We included 48 trials of 6273 participants. Dexmedetomidine reduced the mean (95%CI) duration of intensive care by 5.0 (2.2–7.7) h, p = 0.001, and tracheal intubation by 1.6 (0.6–2.7) h, p = 0.003. The relative risk (95%CI) for postoperative delirium was 0.58 (0.43–0.78), p = 0.001; 0.76 (0.61–0.95) for atrial fibrillation, p = 0.015; and 0.49 (0.25–0.97) for short-term mortality, p = 0.041. Bradycardia and hypotension were not significantly affected. Trial sequential analysis was consistent with the primary meta-analysis. Adjustments for possible false data reduced the mean (95%CI) reduction in duration of intensive care and tracheal intubation by dexmedetomidine to 3.6 (1.8–5.4) h and 0.8 (0.2–1.4) h, respectively. Binary adjustment for methodological quality at a Joanna Briggs Institute score threshold of 10 did not alter the results significantly. In summary, peri-operative dexmedetomidine reduced the durations of intensive care and tracheal intubation and the incidence of short-term mortality after adult cardiac surgery. The reductions in intensive care stay and tracheal intubation may or may not be considered clinically useful, particularly after adjustment for possible false data.     

The effect of a multidisciplinary care bundle on the incidence of delirium after hip fracture surgery: a quality improvement study

Delirium is a common complication following hip fracture surgery. We introduced a peri-operative care bundle that standardised management in the emergency department, operating theatre and ward. This incorporated: use of fascia iliaca blocks; rationalisation of analgesia; avoidance of drugs known to trigger delirium; a regular education program for staff; and continuous auditing of compliance. The study was conducted between June 2017 and December 2018. We recruited 150 patients before (control group) and 150 patients after (care bundle group) the introduction of the care bundle. In patients having surgery for a hip fracture, there was a lower incidence of delirium on the third postoperative day in the care bundle group compared with the control group (33 patients (22%) vs. 49 patients (33%)), respectively; p = 0.04). Patients in the care bundle group had an adjusted OR of 2.2 (95%CI 1.1–4.4) (p = 0.03) for the avoidance of delirium on the third postoperative day. There was no difference between groups for the secondary outcome measures (measured at 30 days postoperatively) including: all-cause mortality; composite morbidity; institutionalisation; and walking status. During the study period, compliance with elements of the care bundle improved in the emergency department (49 patients (33%) compared with 85 patients (59%); p < 0.001) and anaesthetic department (40 patients (27%) compared with 104 patients (69%); p < 0.001), while orthogeriatrics maintained a high level of compliance (140 patients (93%) compared with 143 patients (95%); p = 0.45). There was a clinically and statistically significant reduction in the incidence of delirium following hip fracture surgery in patients treated with a multidisciplinary care bundle.     

A comparison of single‐dose dexmedetomidine or propofol on the incidence of emergence delirium in children undergoing general anaesthesia for magnetic resonance imaging

Emergence delirium is a significant problem in children regaining consciousness following general anaesthesia. We compared the emergence characteristics of 120 patients randomly assigned to receive a single intravenous dose of dexmedetomidine 0.3 μg.kg^?1, propofol 1 mg.kg^?1, or 10 ml saline 0.9% before emerging from general anaesthesia following a magnetic resonance imaging scan. Emergence delirium was diagnosed as a score of 10 or more on the Paediatric Anaesthesia Emergence Delirium scale. The incidence of emergence delirium was 42.5% in the dexmedetomidine group, 33.3% in the propofol group and 41.5% in the saline group (p = 0.671). Three patients in the dexmedetomidine group, none in the propofol group and two in the saline group required pharmacological intervention for emergence delirium (p = 0.202). Administration of neither dexmedetomidine nor propofol significantly reduced the incidence, or severity, of emergence delirium. The only significant predictor for emergence delirium was the time taken to awaken from general anaesthesia, with every minute increase in wake‐up time reducing the odds of emergence delirium by 7%.     

Association between perioperative hypotension and postoperative delirium and atrial fibrillation after cardiac surgery: A post-hoc analysis of the DECADE trial

Study objectiveTo test the hypotheses that in adults having cardiac surgery with cardio-pulmonary bypass, perioperative hypotension increases the risk of delirium and atrial fibrillation during the initial five postoperative days.DesignSub-analysis of the DECADE multi-center randomized trial.SettingPatients who had cardiac surgery with cardiopulmonary bypass at the Cleveland Clinic.InterventionsIn the underlying trial, patients were randomly assigned 1:1 to dexmedetomidine or normal saline placebo.MeasurementsIntraoperative mean arterial pressures were recorded at 1-min intervals from arterial catheters or at 1–5-min intervals oscillometrically. Postoperative blood pressures were recorded every half-hour or more often. The co-primary outcomes were atrial fibrillation and delirium occurring between intensive care unit admission and the earlier of postoperative day 5 or hospital discharge. Delirium was assessed twice daily during the initial 5 postoperative days while patients remained hospitalized with the Confusion Assessment Method for the intensive care unit. Assessments were made by trained research fellows who were blinded to the dexmedetomidine administration.Main resultsThere was no significant association between intraoperative hypotension and delirium, with an adjusted odds ratio of 0.94 (95% CI: 0.81, 1.09; P = 0.419) for a doubling in AUC of mean arterial pressure (MAP) <60 mmHg. An increase in intraoperative AUC of MAP <60 mmHg was not significantly associated with the odds of atrial fibrillation (adjusted odds ratio = 0.99; 95% CI: 0.87, 1.11; P = 0.819). Postoperative MAP <70 mmHg per hour 1.14 (97.5% CI: 1.04,1.26; P = 0.002) and MAP <80 mmHg per hour 1.05 (97.5%: 1.01, 1.10; P = 0.010) were significantly associated with atrial fibrillation.ConclusionsIn patients having cardiac surgery with cardio-pulmonary bypass, neither intraoperative nor postoperative hypotension were associated with delirium. Postoperative hypotension was associated with atrial fibrillation, although intraoperative hypotension was not.     

The influence of orthopedic surgery on the incidence of post-operative delirium in geriatric patients: results of a prospective observational study

BackgroundPostoperative delirium (PD) is a major concern in geriatric patients undergoing orthopedic surgery. This prospective observational study aims to examine the incidence of PD, to identify intervention-specific risk factors and to investigate the influence of orthopedic surgery on delirium.MethodsFrom 2019 to 2020, 132 patients ≥70 years of age with endoprosthetic (Group E) or spinal surgery (Group S) were included. Upon admission, the ISAR score, the Nursing Delirium Screening Scale, potential risk factors, the ASA score, duration of surgery, type of anesthesia, blood loss, and hemoglobin drop were recorded. For risk factor analysis patients were grouped into Group D (delirium) and Group ND (no delirium). Primary endpoint was the occurrence of PD.ResultsOf 132 patients, 50 were included in Group E and 82 in Group S. Mean age and ISAR score were not significantly different between groups. Delirium rate in Group E and S was 12% vs. 18% (p = 0.3). Differences could be observed between Group D and ND in duration of surgery (173 min vs. 112 min, p = 0.02), postoperative hemoglobin drop (3.2 g/dl vs. 2.3 g/dl; p = 0.026), history of PD (23% vs. 11%, p = 0.039) and use of isoflurane (6 vs. 2). Type of surgery was not an independent risk factor (p = 0.26).ConclusionSpecific type of orthopedic surgery is not an independent risk factor for PD. Prevention of PD should focus on duration of surgery and blood loss, particularly in patients with a history of PD. A possible delirogenic potential of isoflurane should be further studied.     

The effect of dexmedetomidine on delirium and agitation in patients in intensive care: systematic review and meta-analysis with trial sequential analysis

Delirium is common in intensive care patients. Dexmedetomidine is increasingly used for sedation in this setting, but its effect on delirium remains unclear. The primary aim of this review was to examine whether dexmedetomidine reduces the incidence of delirium and agitation in intensive care patients. We sought randomised clinical trials in MEDLINE, EMBASE, PubMed and CENTRAL from their inception until June 2018. Observational studies, case reports, case series and non-systematic reviews were excluded. Twenty-five trials including 3240 patients were eligible for inclusion in the data synthesis. In the patients who received dexmedetomidine (eight trials, 1425 patients), delirium was reduced, odds ratio (95%CI) 0.36 (0.26–0.51), p < 0.001 and high quality of evidence. The use of dexmedetomidine was associated with a reduced incidence of agitation, OR (95%CI) 0.34 (0.20–0.59), p < 0.001, moderate quality of evidence. Patients who were randomly assigned to dexmedetomidine had a significantly higher incidence of bradycardia, OR (95%CI) 2.18 (1.46–3.24), p < 0.001, moderate quality of evidence; and hypotension, OR (95%CI) 1.89 (1.48–2.41), p < 0.001, high quality of evidence. We found no evidence of an effect on mortality, OR (95%CI) 0.86 (0.66–1.10), p = 0.23, moderate quality of evidence. The trial sequential analyses for the incidence of delirium, bradycardia and hypotension was conclusive but not for the incidence of agitation and mortality. In summary, this meta-analysis suggests that dexmedetomidine reduces the incidence of delirium and agitation in intensive care patients. The general quality of evidence ranged from moderate to high.     

Cerebral oximetry and postoperative delirium after cardiac surgery: a randomised,controlled trial

Postoperative delirium is associated with increased morbidity and mortality. We hypothesised that restoration of regional cerebral oxygen desaturation would reduce the incidence of postoperative delirium in elderly patients after cardiac surgery. After institutional ethics review board approval and informed consent, a double‐blinded, prospective, randomised, controlled trial was conducted in patients ≥ 60 years of age undergoing cardiac surgery with cardiopulmonary bypass. In the intervention group, an algorithm was commenced if regional cerebral oxygen saturation decreased below 75% of baseline value for 1 min or longer. In the control group, the cerebral oximetry monitor screen was electronically blinded. Assessment of delirium was performed with confusion assessment method for intensive care unit or confusion assessment method after discharge from intensive care unit at 12‐h intervals for seven postoperative days. Postoperative delirium was present in 30 out of 123 (24.4%) and 31 out of 126 (24.6%) patients in the intervention and control groups, respectively, odds ratio 0.98 (95%CI 0.55–1.76), p = 0.97. Postoperative delirium was present in 20 (71%) out of 28 and in 41 (18%) out of 221 patients with baseline regional cerebral oxygen saturation ≤ 50, or > 50%, respectively, p = 0.0001. Higher baseline regional cerebral oxygen saturation and body mass index were protective against postoperative delirium. Restoration of regional cerebral oxygen desaturation did not result in lower postoperative delirium after cardiac surgery. Pre‐operative regional cerebral oxygen saturation ≤ 50% was associated with increased postoperative delirium rates in elderly patients following cardiac surgery.     

Cardiovascular events in patients undergoing hip fracture surgery treated with remote ischaemic preconditioning: 1-year follow-up of a randomised clinical trial

Remote ischaemic preconditioning reduces the risk of myocardial injury within 4 days of hip fracture surgery. We aimed to investigate the effect of remote ischaemic preconditioning on the incidence of major adverse cardiovascular events 1 year after hip fracture surgery. We performed a phase-2, multicentre, randomised, observer-blinded, clinical trial between February 2015 and September 2017. We studied patients aged ≥ 45 years with a hip fracture and a minimum of one cardiovascular risk factor. Patients were allocated randomly to remote ischaemic preconditioning applied just before surgery or no treatment (control group). Remote ischaemic preconditioning was performed on the upper arm with a tourniquet in four cycles of 5 min ischaemia and 5 min reperfusion. Primary outcome was the occurrence of major adverse cardiovascular events within 1 year of surgery. A total of 316 patients were allocated randomly to the remote ischaemic preconditioning group and 309 patients to the control group. Major adverse cardiovascular events occurred in 43 patients (13.6%) in the remote ischaemic preconditioning group compared with 51 patients (16.5%) in the control group (adjusted hazard ratio (95%CI) 0.83 (0.55–1.25); p = 0.37). Fewer patients in the remote ischaemic preconditioning group had a myocardial infarction (11 (3.5%) vs. 22 (7.1%); hazard ratio (95%CI) 0.48 (CI 0.23–1.00); p = 0.04). Remote ischaemic preconditioning did not reduce the occurrence of major adverse cardiovascular events within 1 year of hip fracture surgery. The effect of remote ischaemic preconditioning on clinical cardiovascular outcomes in non-cardiac surgery needs confirmation in appropriately powered randomised clinical trials.     

Perioperative dexmedetomidine administration to prevent delirium in adults after non-cardiac surgery: A systematic review and meta-analysis

Study objectiveTo evaluate the efficacy of perioperative dexmedetomidine (DEX) administration for preventing delirium in adults after non-cardiac surgery.DesignSystematic review and meta-analysis of randomized controlled trials (RCTs).InterventionsPerioperative administration of DEX to prevent delirium in adults following non-cardiac surgery.MeasurementsThe incidence of postoperative delirium (POD).MethodsThe databases of PubMed, Embase and Cochrane Central Register were searched from inception to Mar 4, 2021 for all available RCTs that assessed DEX for POD in adults after non-cardiac surgery. Risk ratio (RR) with a 95% confidence interval (CI) was calculated for dichotomous data. Standardized mean difference (SMD) was calculated for continuous data. Risk of bias was assessed using the second version of the Cochrane risk-of-bias tool for RCTs (RoB 2.0), and the level of certainty for main outcomes were assessed by the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology.Main resultsThirteen studies, including the meta-analysis with a total of 4015 patients (DEX group: 2050 patients; placebo group: 1965 patients), showed that DEX significantly reduced the incidence of POD in adults after non-cardiac surgery compared with control group (RR: 0.60; 95%CI: 0.46 to 0.77, P = 0.0001, I² = 55%, GRADE = moderate). Meanwhile, there was a statistical difference by the subgroup analysis between the mean age ≥ 65 years group and the mean age<65 years group. There were no statistical differences in length of hospital stay following surgery (SMD: -0.36; 95%CI: −0.80 to 0.07, P = 0.1, I² = 97%, GRADE = low) and all-cause mortality rate (RR:0.57; 95%CI: 0.25 to 1.28, P < 0.17, I² = 0%, GRADE = moderate) compared with placebo group. However, Meta-analysis showed that DEX administration significantly resulted in intraoperative bradycardia when compared with placebo group (RR: 1.39; 95%CI: 1.14 to 1.69, P = 0.0009, I² = 0%, GRADE = high), and as well as intraoperative hypotension (RR: 1.25; 95%CI: 1.11 to 1.42, P = 0.0004, I² = 0%, GRADE = high).ConclusionThis systematic review and meta-analysis suggests that perioperative administration of DEX could significantly reduce the incidence of POD in patients elder than 65 years following non-cardiac surgery. However, there was no definite evidence that perioperative DEX could reduce the incidence of POD in patients younger than 65 years of age after non-cardiac surgery. In addition, perioperative DEX administration was associated with an elevated risk of bradycardia and hypotension.     

Dexmedetomidine versus propofol for prolonged sedation in critically ill trauma and surgical patients

Backgroundand Purpose: Currently, dexmedetomidine versus propofol has primarily been studied in medical and cardiac surgery patients with outcomes indicating safe and effective sedation. The purpose of this study was to assess the efficacy of dexmedetomidine versus propofol for prolonged sedation in trauma and surgical patients.MethodsThis was a single-center prospective study conducted in the Trauma/Surgical Intensive Care Unit (ICU) at a Level I academic trauma center. It included patients 18 years of age or older requiring mechanical ventilation who were randomly assigned based on unit bed location to receive either dexmedetomidine or propofol. The primary outcome was duration of mechanical ventilation. Secondary outcomes included mortality; proportion of time in target sedation; incidence of delirium, hypotension, and bradycardia; and ICU and hospital length of stay (LOS).ResultsA total of 57 patients were included. Baseline characteristics were similar between groups. There was no significant difference in duration of mechanical ventilation (median [IQR]) between the dexmedetomidine (78.5[125] hours) and propofol (105[130] hours; p = 0.15) groups. There was no difference between groups in ICU mortality, ICU and hospital LOS, or incidence of delirium. Safety outcomes were also similar. Patients in the dexmedetomidine group spent a significantly greater percentage of time in target sedation (98[8] %) compared to propofol group (92[10] %; p = 0.02).ConclusionsOur results suggest that, similar to medical and cardiac surgery patients, dexmedetomidine and propofol are safe and effective sedation agents in critically ill trauma and surgical patients; however, dexmedetomidine achieves target sedation better than propofol for this specific population.     

Methylene blue reduces incidence of early postoperative cognitive disorders in elderly patients undergoing major non-cardiac surgery: An open–label randomized controlled clinical trial

Study objectiveThe purpose of the present study was to investigate whether methylene blue (MB) could reduce the incidences of postoperative delirium (POD) and early postoperative cognitive dysfunction (POCD) in elderly patients undergoing major non-cardiac surgery.DesignProspective, randomized, open–label clinical trial.SettingUniversity-affiliated hospital.PatientsTwo hundred and forty-eight elderly patients scheduled for non-cardiac surgery.InterventionsElderly patients undergoing non-cardiac major surgery were randomly assigned to MB group (n = 124), who receiving intravenous infusion of 2 mg/kg MB within 60 min immediately after anesthetic induction, or control group (n = 124), who receiving equal volume saline in the same way.MeasurementsAll patients were evaluated with delirium and neuropsychological batteries before and after surgery, as well as perioperative adverse events. Two plasma biomarkers superoxide dismutase (SOD) and homocysteine (HCY) were measured pre- and post-operatively.Main resultsThere were total 39 cases(15.7%)experienced POD. The incidence of POD in MB group was significantly less than that in control group (7.3% vs. 24.2%, OR = 0.24, 95%CI: 0.11–0.53, p < 0.001). The incidence of early POCD at postoperative 7th day in MB group was also less than that in control group (16.1% vs. 40.2%, OR = 0.30, 95% CI: 0.16–0.57, p < 0.001). The adverse events were comparable in both groups. In addition, there was no significant correlation between POD/POCD and levels of SOD or HCY.ConclusionWe conclude that intraoperative intravenous 2 mg/kg MB could significantly reduce the incidences of POD and early POCD in elderly surgical patients, while not remarkably increase incidence of perioperative adverse events, suggesting MB may be clinically effective and safe for prevention of early postoperative neurocognitive disorders.     

Steroids to reduce the impact on delirium (STRIDE): a double-blind,randomised, placebo-controlled feasibility trial of pre-operative dexamethasone in people with hip fracture

Neuro-inflammation may be important in the pathogenesis of postoperative delirium following hip fracture surgery. Studies have suggested a potential role for steroids in reducing postoperative delirium; however, the potential efficacy and safety of pre-operative high-dose dexamethasone in this specific population is largely unknown. Conducting such a study could be challenging, considering the multidisciplinary team involvement and the emergency nature of the surgery. The aim of this study was to assess feasibility and effectiveness of dexamethasone given as early as possible following hospital admission for hip fracture, to inform whether a full-scale trial is warranted. This single-centre, randomised, double-blind, placebo-controlled study randomly allocated 79 participants undergoing hip fracture surgery to dexamethasone 20 mg or placebo pre-operatively. Eligibility and recruitment rates, timing of the intervention and adverse events were recorded. Incidence and severity of postoperative delirium were assessed using the 4AT delirium screening tool and the Memorial Delirium Assessment Scale. Postoperative pain, length of stay and mortality were also assessed. The eligibility rate for inclusion was 178/527 (34%), and 57/178 (32%) of eligible patients presented to hospital when no researcher was available (e.g. after-hours, weekends, public holidays). Recruitment was limited mainly by ethical limitations (not including patients with impaired cognition) and lack of weekend staffing. Median (IQR [range]) time from emergency department admission to drug administration was 13.3 (5.9–17.6 [1.8–139.6]) hours. There was a significant difference in delirium severity scores, favouring the dexamethasone group: median (IQR [range]) 5 (3–6 [3–7]) vs. 9 (6–13 [5–14]) in the placebo group, with the probability of superiority effect size being 0.89, p = 0.010. Delirium incidence did not differ between groups: 6/40 (15%) in the dexamethasone group vs. 9/39 (23%) in the placebo group, relative risk (95%CI) 0.65 (0.22–1.65), p = 0.360). A larger randomised controlled trial is feasible and ideally this should include people with existing cognitive impairment, seven days-a-week cover and a multicentre design.     

Efficacy of risperidone for prevention of postoperative delirium in cardiac surgery

This randomised, double-blinded, placebo-controlled study was primarily aimed to evaluate the potential of risperidone to prevent postoperative delirium following cardiac surgery with cardiopulmonary bypass and the secondary objective was to explore clinical factors associated with postoperative delirium. One-hundred-and-twenty-six adult patients undergoing elective cardiac surgery with cardiopulmonary bypass were randomly assigned to receive either 1 mg of risperidone or placebo sublingually when they regained consciousness. Delirium and other outcomes were assessed. The confusion assessment method for intensive care unit was used to assess postoperative delirium. The incidence of postoperative delirium in the risperidone group was lower than the placebo group (11.1% vs. 31.7% respectively, P=0.009, relative risk = 0.35, 95% confidence interval [CI] = 0.16-0.77). Other postoperative outcomes were not statistically different between the groups. In exploring the factors associated with delirium, univariate analysis showed many factors were associated with postoperative delirium. However multiple logistic regression analysis showed a lapse of 70 minutes from the time of opening eyes to following commands and postoperative respiratory failure were independent risk factors (P=0.003, odds ratio [OR] = 4.57, 95% CI = 1.66-12.59 and P=0.038, OR = 13.78, 95% CI = 1.15-165.18 respectively). A single dose of risperidone administered soon after cardiac surgery with cardiopulmonary bypass reduces the incidence of postoperative delirium. Multiple factors tended to be associated with postoperative delirium, but only the time from opening eyes to following commands and postoperative respiratory failure were independent risk factors in this study.     

Incidence of preoperative instrumental activities of daily living (IADL) dependence and adverse outcomes in older surgical patients: A systematic review and meta-analysis

Study objectiveInstrumental activities of daily living (IADLs) are essential to patient function and quality of life after surgery. In older surgical patients, the incidence of preoperative IADL dependence has not been well characterized in the literature. This systematic review and meta-analysis aimed to determine the pooled incidence of preoperative IADL dependence and the associated adverse outcomes in the older surgical population.DesignSystematic review and meta-analysis.SettingMEDLINE, MEDLINE Epub Ahead of Print and In-Process, In-Data-Review & Other Non-Indexed Citations, Embase/Embase Classic, Cochrane CENTRAL, and Cochrane Database of Systematic Reviews, ClinicalTrials.Gov, the WHO ICTRP (International Clinical Trials Registry Platform) were searched for relevant articles from 1969 to April 2022.PatientsPatients aged ≥60 years old undergoing surgery with preoperative IADL assessed by the Lawton IADL Scale.InterventionsPreoperative assessment.MeasurementThe primary outcome was the pooled incidence of preoperative IADL dependency. Additional outcomes included post-operative mortality, postoperative delirium [POD], functional status improvement, and discharge disposition.Main resultsTwenty-one studies (n = 5690) were included. In non-cardiac surgeries, the pooled incidence of preoperative IADL dependence was 37% (95% CI: 26.0%, 48.0%) among 2909 patients. Within cardiac surgeries, the pooled incidence of preoperative IADL dependence was 53% (95% CI: 24.0%, 82.0%) among 1074 patients. Preoperative IADL dependence was associated with an increased risk of postoperative delirium than those without IADL dependence (44.9% vs 24.4, OR 2.26; 95% CI: 1.42, 3.59; I²: 0%; P = 0.0005).ConclusionsThere is a high incidence of IADL dependence in older surgical patients undergoing non-cardiac and cardiac surgery. Preoperative IADL dependence was associated with a two-fold risk of postoperative delirium. Further work is needed to determine the feasibility of using the IADL scale preoperatively as a predictive tool for postoperative adverse outcomes.     

Acute peri-operative neurocognitive disorders: a narrative review

Peri-operative neurocognitive disorders are the most common complication experienced by older individuals undergoing anaesthesia and surgery. Peri-operative neurocognitive disorders, particularly postoperative delirium, result in long-term poor outcomes including: death; dementia; loss of independence; and poor cognitive and functional outcomes. Recent changes to the nomenclature of these disorders aims to align peri-operative neurocognitive disorders with cognitive disorders in the community, with consistent definitions and clinical diagnosis. Possible mechanisms include: undiagnosed neurodegenerative disease; inflammation and resulting neuroinflammation; neuronal damage; and comorbid systemic disease. Pre-operative frailty represents a significant risk for poor postoperative outcomes; it is associated with an increase in the incidence of cognitive decline at 3 and 12 months postoperatively. In addition to cognitive decline, frailty is associated with poor functional outcomes following elective non-cardiac surgery. It was recently shown that 29% of frail patients died or experienced institutionalisation or new disability within 90 days of major elective surgery. Identification of vulnerable patients before undergoing surgery and anaesthesia is the key to preventing peri-operative neurocognitive disorders. Current approaches include: pre-operative delirium and cognitive screening; blood biomarker analysis; intra-operative management that may reduce the incidence of postoperative delirium such as lighter anaesthesia using processed electroencephalography devices; and introduction of guidelines which may reduce or prevent delirium and postoperative neurocognitive disorders. This review will address these issues and advocate for an approach to care for older peri-operative patients which starts in the community and continues throughout the pre-operative, intra-operative, postoperative and post-discharge phases of care management, involving multidisciplinary medical teams, as well as family and caregivers wherever possible.     

Risk factors and effect of postoperative delirium on adverse surgical outcomes in older adults after elective abdominal cancer surgery in Taiwan

BackgroundPostoperative delirium (POD) is a common complication in older adults, with unknown epidemiology and effects on surgical outcomes in Asian geriatric cancer patients. This study evaluated incidence, risk factors, and association between adverse surgical outcomes and POD after intra-abdominal cancer surgery in Taiwan.MethodsOverall, 345 patients aged ≥65 years who underwent elective abdominal cancer surgery at a medical center in Taiwan were prospectively enrolled. Delirium was assessed daily using the Confusion Assessment Method. Univariate and multivariate logistic regression analyses investigated risk factors for POD occurrence and estimated the association with adverse surgical outcomes.ResultsPOD occurred in 19 (5.5%) of the 345 patients. Age ≥73 years, Charlson comorbidity index ≥3, and operative time >428 min were independent predictors for POD occurrence. Patients presenting with one, two, and three risk factors had 4.1-fold (95% confidence interval [CI], 0.4–35.8, p = 0.20), 17.4-fold (95% CI, 2.2–138, p = 0.007), and 30.8-fold likelihood (95% CI, 2.9–321, p = 0.004) for POD occurrence, respectively. Patients with POD had a higher probability of prolonged hospital stay (adjusted odds ratio [OR] 2.8; 95% CI, 1.0–8.1; p = 0.037), intensive care stay (adjusted OR: 3.9; 95% CI, 1.5–10.5; p = 0.008), 30-day readmission (adjusted OR 3.1; 95% CI, 1.1–9.7; p = 0.039), and 90-day postoperative death (adjusted OR: 4.2; 95% CI, 1.0–17.7; p = 0.041).ConclusionPOD occurrence was significantly associated with adverse surgical outcomes in geriatric patients undergoing elective abdominal cancer surgery, highlighting the importance of early POD identification in geriatric patients to improve postoperative care quality.     

The relationship between obstructive sleep apnoea and postoperative delirium and pain: an observational study of a surgical cohort

Patients with obstructive sleep apnoea are at increased risk of adverse postoperative outcomes, such as cardiac and respiratory complications. It has been hypothesised that obstructive sleep apnoea also increases the risk for postoperative delirium and acute postoperative pain. We conducted a retrospective, observational study investigating the relationship of obstructive sleep apnoea with postoperative delirium and acute postoperative pain severity. Patients were classified as being at high risk for obstructive sleep apnoea if they had been diagnosed with this condition, or if they were positive for more than four factors using the ‘STOP-BANG’ screening tool. Adjusted logistic regression was used to investigate the association between obstructive sleep apnoea and postoperative delirium, and multivariable linear regression to study the relationship between obstructive sleep apnoea and postoperative pain severity. The incidence of postoperative delirium was 307 in 1441 patients (21.3%; 95%CI 19.2–23.5%). In unadjusted analysis, high risk for obstructive sleep apnoea was associated with delirium, with an odds ratio (95%CI) of 1.77 (1.22–2.57; p = 0.003). After adjustment for pre-specified variables, the association was not statistically significant with odds ratio 1.34 (0.80–2.23; p = 0.27). The mean (SD) maximum pain (resting or provoked) reported for the entire cohort was 63.8 (27.9) mm on a 0–100 mm visual analogue scale. High risk for obstructive sleep apnoea was not associated with postoperative pain severity (β-coefficient 2.82; 95%CI, −2.34–7.97; p = 0.28). These findings suggest that obstructive sleep apnoea is unlikely to be a strong risk factor for postoperative delirium or acute postoperative pain severity.