Impact of postoperative cardiovascular complications on 30-day mortality after major abdominal surgery: an international prospective cohort study

Cardiovascular complications after major surgery are associated with increases in morbidity and mortality. There is confusion over definitions of cardiac injury or complications, and variability in the assessment and management of patients. This international prospective cohort study aimed to define the incidence and timing of these complications and to investigate their impact on 30-day all-cause mortality. We performed a prospective, international cohort study between January 2022 and May 2022. Data were collected on consecutive patients undergoing major abdominal surgery in 446 hospitals from 28 countries across Europe. The primary outcome measure was cardiovascular complications as defined by the Standardised Endpoints for Perioperative Medicine-Core Outcome Measures for Perioperative and Anaesthetic Care initiative up to 30 days after surgery. The secondary outcome was 30-day postoperative mortality. This study included 24,203 patients, of whom 611 (2.5%) developed cardiovascular complications. In total, 458 (1.9%) patients died within 30 days of surgery, of which 123 (26.9%) deaths were judged to be cardiac-related. Mortality rates were higher in patients who developed postoperative cardiovascular complications than in those who did not (19.8% vs. 1.4%), which persisted after risk adjustment (hazard ratio (95%CI) 4.15 (3.14-5.48)). We estimated an absolute risk reduction (95%CI) of 0.4 (0.3-0.5) in mortality in the absence of all cardiovascular complications. This would confer a relative risk reduction in mortality of 21.1% if all cardiovascular complications were prevented. Postoperative cardiovascular complications are relatively common and occur early after major abdominal surgery. However, over 1 in 5 postoperative deaths were attributable to these complications, highlighting an important area for future randomised trials.

Evolving concepts on perioperative nutrition of sarcopenic cancer patients

The recent recognition of the association of sarcopenia with an increased risk of complications after a surgical procedure calls for rethinking the proper approach of the perioperative care in cancer patients. Sarcopenia is broadly considered in literature according to three different definitions: loss of muscle mass, loss of muscle mass plus reduced muscle function and myosteatosis. The aim of this short review on this issue is to define the excess of risk by type of primary and of surgical procedure, depending on the definition of sarcopenia, to speculate on this association (casual versus causal) and to examine the current therapeutical approaches. The analysis of the data shows that sarcopenia, defined as loss of muscle mass plus reduced muscle function, has the higher predictive power for the occurrence of postoperative complications than the two other definitions, and any definition of sarcopenia works better than the usual indexes or scores of surgical risk. Our analysis supports the concept that: a) sarcopenia is frequently associated with inflammation, but inflammation cannot be considered the only or the absolute cause for sarcopenia, b) sarcopenia is not a simple marker of risk but can have a direct role in the increase of risk. Data on perioperative care of sarcopenic cancer patients are scanty but a correct approach cannot rely on nutritional support alone but on a combined approach of optimized nutrition and exercise, hopefully associated with an anti-inflammatory treatment. This strategy should be applied proactively in keeping with the recent recommendations of the American Society of Clinical Oncology for the medical treatment of advanced cancer patients even if a clear demonstration of effectiveness is still lacking.

Spinal Anesthesia Reduces Perioperative Polypharmacy and Opioid Burden in Patients Over 65 Who Undergo Transforaminal Lumbar Interbody Fusion

BACKGROUND

Polypharmacy and opioid administration are thought to increase the risk of postoperative cognitive dysfunction and delirium in elderly patients. Spinal anesthesia (SA) holds potential to reduce perioperative polypharmacy in spine surgery. As more geriatric patients undergo spine surgery, understanding how SA can reduce polypharmacy and opioid administration is warranted. We aim to compare the perioperative polypharmacy and dose of administered opioids in patients ≥65 years who undergo transforaminal lumbar interbody fusion (TLIF) under SA versus general anesthesia (GA).

METHODS

A retrospective analysis of 200 patients receiving a single-surgeon TLIF procedure at a single academic center (2014-2021) was performed. Patients underwent the procedure with SA (n = 120) or GA (n = 80). Demographic, procedural, and medication data were extracted from the medical record. Opioid consumption was quantified as morphine milligram equivalents (MME). Statistical analyses included χ2 or Student's t-test.

RESULTS

Patients receiving SA were administered 7.45 medications on average versus 12.7 for GA patients (P < 0.001). Average perioperative opioid consumption was 5.17 MME and 20.2 MME in SA and GA patients, respectively (P < 0.001). The number of patients receiving antiemetics and opioids remained comparable postoperatively, with a mean of 32.2 MME in the GA group versus 27.5 MME in the SA group (P = 0.14). Antiemetics were administered less often as a prophylactic in the SA group (32%) versus 86% in the GA group (P < 0.001).

CONCLUSIONS

SA reduces perioperative polypharmacy in patients ≥65 years undergoing TLIF procedures. Further research is necessary to determine if this reduction correlates to a decrease the incidence of postoperative cognitive dysfunction and delirium.

An exploratory research report on brain mineralization in postoperative delirium and cognitive decline

Delirium is a severe postoperative complication associated with poor overall and especially neurocognitive prognosis. Altered brain mineralization is found in neurodegenerative disorders but has not been studied in postoperative delirium and postoperative cognitive decline. We hypothesized that mineralization-related hypointensity in susceptibility-weighted magnetic resonance imaging (SWI) is associated with postoperative delirium and cognitive decline. In an exploratory, hypothesis-generating study, we analysed a subsample of cognitively healthy patients ≥65 years who underwent SWI before (N = 65) and 3 months after surgery (N = 33). We measured relative SWI intensities in the basal ganglia, hippocampus and posterior basal forebrain cholinergic system (pBFCS). A post hoc analysis of two pBFCS subregions (Ch4, Ch4p) was conducted. Patients were screened for delirium until the seventh postoperative day. Cognitive testing was performed before and 3 months after surgery. Fourteen patients developed delirium. After adjustment for age, sex, preoperative cognition and region volume, only pBFCS hypointensity was associated with delirium (regression coefficient [90% CI]: B = -15.3 [-31.6; -0.8]). After adjustments for surgery duration, age, sex and region volume, perioperative change in relative SWI intensities of the pBFCS was associated with cognitive decline 3 months after surgery at a trend level (B = 6.8 [-0.9; 14.1]), which was probably driven by a stronger association in subregion Ch4p (B = 9.3 [2.3; 16.2]). Brain mineralization, particularly in the cerebral cholinergic system, could be a pathomechanism in postoperative delirium and cognitive decline. Evidence from our studies is limited because of the small sample and a SWI dataset unfit for iron quantification, and the analyses presented here should be considered exploratory.

Feasibility and Safety of Bridging Antiplatelet Therapy with Cangrelor in Neuro-Oncology: A Preliminary Experience

Antiplatelet therapy is mandatory for prevention of thrombotic events in patients with a recent history of acute coronary syndromes and/or percutaneous coronary interventions. However, if an urgent surgery is required during antiplatelet therapy, a compromise between the ischemic/thrombotic and hemorrhagic risk has to be reached. Different bridging schemes are reported in the literature, but there is no clear consensus on the optimal treatment strategy in terms of efficacy and safety. Although some indications about the perioperative management of antiplatelet therapy regarding specific surgical specializations are available, balancing the thrombotic and hemorrhagic risk on an individual basis, no evidence referring to neurosurgical or neuro-oncologic procedures is reported. Herein, we present our preliminary experience in the perioperative management of a patient who underwent a neurosurgical procedure for the resection of a primary malignant brain tumor using an intravenous P2Y12 inhibitor (cangrelor) as bridging therapy after a recent acute myocardial infarction treated with primary percutaneous coronary intervention and stenting. The oral P2Y12 inhibitor (clopidogrel) was withdrawn 5 days prior to the surgical procedure and continuous infusion of cangrelor was started 3 days before the surgery at a dose of 0.75 μg/kg/min. Cangrelor was discontinued 2 hours before surgery and resumed 72 hours after tumor resection for further 60 hours. Neither cangrelor-related bleeding nor cardiac ischemic events were observed in the perioperative period and the following 90 days, supporting data regarding the feasibility and safety of this bridging scheme. Further studies are needed to confirm our promising results.

Risk stratification and predictive modeling of postoperative delirium in chronic subdural hematoma

Background- Postoperative delirium is a common complication associated with the elderly, causing increased morbidity and prolonged hospital stay. However, its risk factors in chronic subdural hematoma patients have not been well studied. Methods- A total of 202 consecutive patients with chronic subdural hematoma at Peking University Third Hospital between January 2018 and January 2023 were enrolled. Various clinical indicators were analyzed to identify independent risk factors for postoperative delirium using univariate and multivariate regression analyses. Delirium risk prediction models were developed as a nomogram and a Markov chain. Results- Out of the 202 patients (age, 71 (IQR, 18); female-to-male ratio, 1:2.7) studied, 63 (31.2%) experienced postoperative delirium. Univariate analysis identified age (p < 0.001), gender (p = 0.014), restraint belt use (p < 0.001), electrolyte imbalance (p < 0.001), visual analog scale score (p < 0.001), hematoma thickness (p < 0.001), midline shift (p < 0.001), hematoma side (p = 0.013), hematoma location (p = 0.018), and urinal catheterization (p = 0.028) as significant factors. Multivariate regression analysis confirmed the significance of restraint belt use (B = 7.657, p < 0.001), electrolyte imbalance (B = -3.993, p = 0.001), visual analog scale score (B = 2.331, p = 0.016), and midline shift (B = 0.335, p = 0.007). Hematoma thickness and age had no significant impact. Conclusion- Increased midline shift and visual analog scale scores, alongside restraint belt use and electrolyte imbalance elevate delirium risk in chronic subdural hematoma surgery. Our prediction models may offer reference value in this context.

Evaluation of venous thromboembolism risk assessment models for hospital inpatients: the VTEAM evidence synthesis

Background

Pharmacological prophylaxis during hospital admission can reduce the risk of acquired blood clots (venous thromboembolism) but may cause complications, such as bleeding. Using a risk assessment model to predict the risk of blood clots could facilitate selection of patients for prophylaxis and optimise the balance of benefits, risks and costs.

Objectives

We aimed to identify validated risk assessment models and estimate their prognostic accuracy, evaluate the cost-effectiveness of different strategies for selecting hospitalised patients for prophylaxis, assess the feasibility of using efficient research methods and estimate key parameters for future research.

Design

We undertook a systematic review, decision-analytic modelling and observational cohort study conducted in accordance with Enhancing the QUAlity and Transparency Of health Research (EQUATOR) guidelines.

Setting

NHS hospitals, with primary data collection at four sites.

Participants

Medical and surgical hospital inpatients, excluding paediatric, critical care and pregnancy-related admissions.

Interventions

Prophylaxis for all patients, none and according to selected risk assessment models.

Main outcome measures

Model accuracy for predicting blood clots, lifetime costs and quality-adjusted life-years associated with alternative strategies, accuracy of efficient methods for identifying key outcomes and proportion of inpatients recommended prophylaxis using different models.

Results

We identified 24 validated risk assessment models, but low-quality heterogeneous data suggested weak accuracy for prediction of blood clots and generally high risk of bias in all studies. Decision-analytic modelling showed that pharmacological prophylaxis for all eligible is generally more cost-effective than model-based strategies for both medical and surgical inpatients, when valuing a quality-adjusted life-year at £20,000. The findings were more sensitive to uncertainties in the surgical population; strategies using risk assessment models were more cost-effective if the model was assumed to have a very high sensitivity, or the long-term risks of post-thrombotic complications were lower. Efficient methods using routine data did not accurately identify blood clots or bleeding events and several pre-specified feasibility criteria were not met. Theoretical prophylaxis rates across an inpatient cohort based on existing risk assessment models ranged from 13% to 91%.

Limitations

Existing studies may underestimate the accuracy of risk assessment models, leading to underestimation of their cost-effectiveness. The cost-effectiveness findings do not apply to patients with an increased risk of bleeding. Mechanical thromboprophylaxis options were excluded from the modelling. Primary data collection was predominately retrospective, risking case ascertainment bias.

Conclusions

Thromboprophylaxis for all patients appears to be generally more cost-effective than using a risk assessment model, in hospitalised patients at low risk of bleeding. To be cost-effective, any risk assessment model would need to be highly sensitive. Current evidence on risk assessment models is at high risk of bias and our findings should be interpreted in this context. We were unable to demonstrate the feasibility of using efficient methods to accurately detect relevant outcomes for future research.

Future work

Further research should evaluate routine prophylaxis strategies for all eligible hospitalised patients. Models that could accurately identify individuals at very low risk of blood clots (who could discontinue prophylaxis) warrant further evaluation.

Study registration

This study is registered as PROSPERO CRD42020165778 and Researchregistry5216.

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: NIHR127454) and will be published in full in Health Technology Assessment; Vol. 28, No. 20. See the NIHR Funding and Awards website for further award information.

Exploring the need for reconsideration of trial design in perioperative outcomes research: a narrative review

"Enhanced recovery after surgery" is a multimodal effort to control perioperative pathophysiology and improve outcome. However, despite advances in perioperative care, postoperative complications and the need for hospitalisation and prolonged recovery continue to be challenging. This is further complicated by procedure-specific and patient-associated risk factors, given the increase in the number of elderly and frail patients with multiple comorbidities undergoing surgery. This paper is a critical assessment of current methodology for trials in perioperative medicine. We make a plea to reconsider the design of future interventional trials to improve surgical outcome, based upon studies of potentially effective interventions, but often without improvements in recovery. The complexity of perioperative pathophysiology necessitates a procedure- and patient-specific approach whenever outcome is assessed or interventions are planned. With improved understanding of perioperative pathophysiology, the way to improve outcomes looks promising, provided that knowledge and established enhanced recovery programmes are integrated in trial design.

Funding

None.

Incidence and outcomes of emergency department patients requiring emergency general surgery: a 5-year retrospective cohort study

AIMS

Patients undergoing emergency general surgery are at high risk of complications and death. Our objectives were to estimate the incidence of emergency general surgery in a Swiss University Hospital, to describe the characteristics and outcomes of patients undergoing such procedures, and to study the impact of age on clinical outcomes.

METHODS

This was a retrospective cohort study of adult patients who visited the emergency department (ED) of Geneva University Hospitals between January 2015 and December 2019. Routinely collected data were extracted from electronic medical records. The primary outcome was the incidence of emergency general surgery among patients visiting the emergency department, defined as general surgery within three days of emergency department admission. We also assessed demographic characteristics, mortality, intensive care unit admission and patient disposition. Multivariable log-binomial regression was used to study the associations of age with intensive care unit (ICU) admission, one-year mortality and dependence at discharge. Age was modelled as a continuous variable using restricted cubic splines and we compared older patients (75th percentile) with younger patients (25th percentile).

RESULTS

Between January 2015 and December 2019, a total of 310,914 emergency department visits met our inclusion criteria. Among them, 3592 patients underwent emergency general surgery within 3 days of emergency department admission, yielding an annual incidence of 116 events per 10,000 emergency department visits (95% CI: 112-119), with a higher incidence in females and young patients. Overall, 5.3% of patients were admitted to ICU, 7.8% were dependent on rehabilitation or assisted living at discharge and 4.8% were dead after one year. Older patients had a higher risk of ICU admission (adjusted risk ratio (aRR) 2.9 [1.5-5.4]), dependence at discharge (aRR 15.3 [5.5-42.4]) and one-year mortality (aRR 5.4 [2.2-13.4]).

CONCLUSION

Emergency department visits resulting in emergency general surgery are frequent, but their incidence decreases with patient age. Mortality, ICU admission and dependence at discharge following emergency general surgery are more frequent in older patients. Taking into account the increased risk for older patients, a shared process is appropriate for making more informed decisions about their options for care.

Peri-operative cardiac arrest in the older frail patient as reported to the 7th National Audit Project of the Royal College of Anaesthetists

Frailty increases peri-operative risk, but details of its burden, clinical features and the risk of, and outcomes following, peri-operative cardiac arrest are lacking. As a preplanned analysis of the 7th National Audit Project of the Royal College of Anaesthetists, we described the characteristics of older patients living with frailty undergoing anaesthesia and surgery, and those reported to the peri-operative cardiac arrest case registry. In the activity survey, 1676 (26%) of 6466 patients aged > 65 y were reported as frail (Clinical Frailty Scale score ≥ 5). Increasing age and frailty were both associated with increasing comorbidities and the proportion of surgery undertaken as an emergency. Except in patients who were terminally ill (Clinical Frailty Scale score 9), increasing frailty was associated with an increased proportion of complex or major surgery. The rate of use of invasive arterial blood pressure monitoring was associated with frailty only until Clinical Frailty Scale score 5, and then plateaued or fell. Of 881 cardiac arrests reported to the 7th National Audit Project, 156 (18%) were in patients aged > 65 y and living with frailty, with an estimated incidence of 1 in 1204 (95%CI 1 in 1027-1412) and a mortality rate of 1 in 2020 (95%CI 1 in 1642-2488), approximately 2.6-fold higher than in adults who were not frail. Hip fracture, emergency laparotomy, emergency vascular surgery and urological surgery were the most common surgical procedures in older patients living with frailty who had a cardiac arrest. We report a high burden of frailty within the surgical population, requiring complex, urgent surgery, and the extent of poorer outcomes of peri-operative cardiac arrest compared with patients of the same age not living with frailty.

Preoperative comprehensive geriatric assessment and multidisciplinary team input in older people undergoing elective orthopaedic surgery: A feasibility trial

OBJECTIVE

To determine the feasibility of preoperative comprehensive geriatric assessment (CGA) and multidisciplinary team (MDT) input for older people undergoing elective orthopaedic surgery in a tertiary New Zealand setting.

METHODS

This single-centre retrospective study included elective orthopaedic patients older than 65 years (and Māori/Pasifika aged greater than 55 years) with hyperpolypharmacy, frailty, neurocognitive disorders and poor functional status. Patients attended a preoperative clinic where they had a geriatrician-led CGA along with MDT input. The feasibility of this preoperative model was assessed using outcomes of acceptability, accessibility and adherence. A qualitative description of patient demographics along with clinic assessment and interventions further describes this pilot experience.

RESULTS

Sixty patients met inclusion criteria. This group were vulnerable older people (median age 77 years), with a high incidence of hyperpolypharmacy (85%), frailty (80%) and neurocognitive disorders (30%). Acceptability was high (97%), along with CGA accessibility (100%); however, MDT accessibility varied (53-90%). Adherence to MDT intervention was low; with only 26% of patients completing physiotherapy sessions and only 29% adhering to dietary advice. Accurate recall was a significant factor contributing to poor adherence. Comprehensive geriatric assessment was demonstrated to be a broad and flexible intervention.

CONCLUSIONS

CGA with MDT input is an acceptable and accessible intervention to be utilised as part of improved preoperative care for the older person undergoing elective orthopaedic surgery. Further consideration around methods to increase adherence in this patient group should be explored. Future research should focus on refining the intervention, and quantifying impact on patient outcomes.

The implementation of a perioperative medicine for older people undergoing surgery service: a qualitative case study

BACKGROUND

The international scale and spread of evidence-based perioperative medicine for older people undergoing surgery (POPS) services has not yet been fully realised. Implementation science provides a structured approach to understanding factors that act as barriers and facilitators to the implementation of POPS services. In this study, we aimed to identify factors that influence the implementation of POPS services in the UK.

METHODS

A qualitative case study at three UK health services was undertaken. The health services differed across contextual factors (population, workforce, size) and stages of POPS service implementation maturity. Semi-structured interviews with purposively sampled clinicians (perioperative medical, nursing, allied health, and pharmacy) and managers (n = 56) were conducted. Data were inductively coded, then thematically analysed using the Consolidated Framework for Implementation Research (CFIR).

RESULTS

Fourteen factors across all five CFIR domains were relevant to the implementation of POPS services. Key shared facilitators included stakeholders understanding the rationale of the POPS service, with support from their networks, POPS champions, and POPS clinical leads. We found substantial variation and flexibility in the way that health services responded to these shared facilitators and this was relevant to the implementation of POPS services.

CONCLUSIONS

Health services planning to implement a POPS service should use health service-specific strategies to respond flexibly to local factors that are acting as barriers or facilitators to implementation. To support implementation of a POPS service, we recommend health services prioritise understanding local networks, identifying POPS champions, and ensuring that stakeholders understand the rationale for the POPS service. Our study also provides a structure for future research to understand the factors associated with 'unsuccessful' implementation of a POPS service, which can inform ongoing efforts to implement evidence-based perioperative models of care for older people.

Dietary Restriction Improves Perioperative Neurocognitive Disorders by Inhibiting Neuroinflammation and Gut Microbial Dysbiosis

Anesthesia/surgery have been identified as potential factors contributing to perioperative neurocognitive disorders, with a notably heightened risk observed in aging populations. One of the primary drivers of this impairment is believed to be neuroinflammation, specifically inflammation of hippocampal microglia. Dietary restriction has demonstrated a favorable impact on cognitive impairment across various disorders, primarily by quelling neuroinflammation. However, the precise influence of dietary restriction on perioperative neurocognitive disorders remains to be definitively ascertained. This investigation aims to explore the effects of dietary restriction on perioperative neurocognitive disorders and propose innovative therapeutic strategies for their management. The model of perioperative neurocognitive disorder was induced through exploratory laparotomy under isoflurane anesthesia. Cognitive performance was evaluated using the open field test, Barnes maze test, and fear conditioning test. The enzyme-linked immunosorbent assay (ELISA) was employed to quantify concentrations of interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) in both serum and hippocampal samples. The Western blot technique was utilized to assess expression levels of hippocampal PSD 95, Synaptophysin, TLR4, MyD88, and NF-kB p65. Microglial polarization was gauged using a combination of reverse transcription quantitative polymerase chain reaction (RT-qPCR) and immunofluorescence labeling techniques. We conducted 16S rRNA sequencing to investigate the impact of dietary restriction on the intestinal flora of aged mice following anesthesia/surgery. Our findings indicate that dietary restrictions have the potential to ameliorate anesthesia/surgery-induced cognitive dysfunction. This effect is achieved through the modulation of gut microbiota, suppression of inflammatory responses in hippocampal microglia, and facilitation of neuronal repair and regeneration.

Development and multicentre validation of the FLEX score: personalised preoperative surgical risk prediction using attention-based ICD-10 and Current Procedural Terminology set embeddings

BACKGROUND

Preoperative knowledge of surgical risks can improve perioperative care and patient outcomes. However, assessments requiring clinician examination of patients or manual chart review can be too burdensome for routine use.

METHODS

We conducted a multicentre retrospective study of 243 479 adult noncardiac surgical patients at four hospitals within the Mass General Brigham (MGB) system in the USA. We developed a machine learning method using routinely collected coding and patient characteristics data from the electronic health record which predicts 30-day mortality, 30-day readmission, discharge to long-term care, and hospital length of stay.

RESULTS

Our method, the Flexible Surgical Set Embedding (FLEX) score, achieved state-of-the-art performance to identify comorbidities that significantly contribute to the risk of each adverse outcome. The contributions of comorbidities are weighted based on patient-specific context, yielding personalised risk predictions. Understanding the significant drivers of risk of adverse outcomes for each patient can inform clinicians of potential targets for intervention.

CONCLUSIONS

FLEX utilises information from a wider range of medical diagnostic and procedural codes than previously possible and can adapt to different coding practices to accurately predict adverse postoperative outcomes.

The functional trajectories of older women having surgery for gynaeoncology cancer: A single site prospective observational study

INTRODUCTION

Population aging longevity and advances in robotic surgery suggest that increasing numbers of older women having gynaeoncological surgery is likely. Postoperative morbidity and mortality are more common in older than younger women with the age-associated characteristics of multimorbidity and frailty being generally predictive of worse outcome. Priorities that inform treatment decisions change during the life course: older patients often place greater' value on quality-of-life-years gained than on life expectancy following cancer treatments. However, data on post-operative cognition, frailty, or functional independence is sparse and not routinely collected. This study aimed to describe the clinical characteristics and trajectory of functional change of older women in the 12 months following gynaeoncological surgery and to explore the associations between them.

MATERIALS AND METHODS

The prospective observational cohort study recruited consecutive women aged 65 or over scheduled for major gynaeoncologic surgery between July 2017 and April 2019. Baseline data on cancer stage, multimorbidity, and geriatric syndromes including cognition, frailty, and functional abilities were collected using standardised tools. Delirium and post-operative morbidity were recorded. Post hospital assessments were collected at 3-, 6-, and 12-months.

RESULTS

Overall, of 103 eligible participants assessed pre-operatively, most (77, 70%) remained independent in personal care at all assessments from discharge to 12 months. Functional trajectories varied widely over the 12 months but overall there was no significant decline or improvement for the 85 survivors. Eleven experienced a clinically significant decline in function at six months. This was associated with baseline low mood (P < 0.05), albeit with small numbers (6 of 11). Cognitive impairment and frailty were associated with lower baseline function but not with subsequent functional decline.

DISCUSSION

There was no clear clinical profile to identify the minority of older adults who experienced a clinically significant decline six months after surgery and for most, the decline was transient. This may be helpful in enabling informed patient consent. Assessment for geriatric syndromes and frailty may improve individual care but our findings do not indicate criteria for segmenting the patient population for selective attention. Future work should focus on causal pathways to potentially avoidable decline in those patients where this is not determined by the cancer itself.

Sarcopenia versus clinical frailty scale in predicting the risk of postoperative mortality after emergency laparotomy: a retrospective cohort study

OBJECTIVES

To compare predictive significance of sarcopenia and clinical frailty scale (CFS) in terms of postoperative mortality in patients undergoing emergency laparotomy METHODS: In compliance with STROCSS statement standards, a retrospective cohort study with prospective data collection approach was conducted. The study period was between January 2017 and January 2022. All adult patients with non-traumatic acute abdominal pathology who underwent emergency laparotomy in our centre were included. The primary outcome was 30-day mortality and secondary outcomes were in-hospital mortality and 90-day mortality. The predictive value of sarcopenia and CFS were compared using the receiver operating characteristic (ROC) curve analysis and multivariable binary logistic regression analysis.

RESULTS

A total of 1043 eligible patients were included. The risk of 30-day mortality, in-hospital mortality, and 90-day mortality were 8%, 10%, and 11%, respectively. ROC curve analysis suggested that sarcopenia is a significantly stronger predictor of 30-day mortality (AUC: 0.87 vs. 0.70, P<0.0001), in-hospital mortality (AUC: 0.79 vs. 0.67, P=0.0011), and 90-day mortality (AUC: 0.79 vs. 0.67, P=0.0009) compared with CFS. Moreover, multivariable binary logistic regression analysis identified sarcopenia as an independent predictor of mortality [coefficient: 4.333, OR: 76.16 (95% CI 37.06-156.52), P<0.0001] but not the CFS [coefficient: 0.096, OR: 1.10 (95% CI 0.88-1.38), P=0.4047].

CONCLUSIONS

Sarcopenia is a stronger predictor of postoperative mortality compared with CFS in patients undergoing emergency laparotomy. It cancels out the predictive value of clinical frailty scale in multivariable analyses; hence among the two variables, sarcopenia deserves to be included in preoperative predictive tools.

Update of the European Society of Anaesthesiology and Intensive Care Medicine evidence-based and consensus-based guideline on postoperative delirium in adult patients

Postoperative delirium (POD) remains a common, dangerous and resource-consuming adverse event but is often preventable. The whole peri-operative team can play a key role in its management. This update to the 2017 ESAIC Guideline on the prevention of POD is evidence-based and consensus-based and considers the literature between 01 April 2015, and 28 February 2022. The search terms of the broad literature search were identical to those used in the first version of the guideline published in 2017. POD was defined in accordance with the DSM-5 criteria. POD had to be measured with a validated POD screening tool, at least once per day for at least 3 days starting in the recovery room or postanaesthesia care unit on the day of surgery or, at latest, on postoperative day 1. Recent literature confirmed the pathogenic role of surgery-induced inflammation, and this concept reinforces the positive role of multicomponent strategies aimed to reduce the surgical stress response. Although some putative precipitating risk factors are not modifiable (length of surgery, surgical site), others (such as depth of anaesthesia, appropriate analgesia and haemodynamic stability) are under the control of the anaesthesiologists. Multicomponent preoperative, intra-operative and postoperative preventive measures showed potential to reduce the incidence and duration of POD, confirming the pivotal role of a comprehensive and team-based approach to improve patients' clinical and functional status.

The association between midazolam premedication and postoperative delirium - a retrospective cohort study

STUDY OBJECTIVE

To evaluate the association between midazolam premedication and postoperative delirium in a large retrospective cohort of patients ≥70 years.

DESIGN

Retrospective cohort study.

SETTING

A single tertiary academic medical center.

PATIENTS

Patients ≥70 years having elective non-cardiac surgery under general anesthesia from 2020 to 2021.

INTERVENTIONS

Midazolam premedication, defined as intravenous midazolam administration prior to induction of general anesthesia.

MEASUREMENTS

The primary outcome, postoperative delirium, was a collapsed composite outcome including at least one of the following: a positive 4A's test during post-anesthesia care unit stay and/or the initial 2 postoperative days; physician or nursing records reporting new-onset confusion as captured by the CHART-DEL instrument; or a positive 3D-CAM test. The association between midazolam premedication and postoperative delirium was assessed using multivariable logistic regression, adjusting for potential confounding variables. As secondary analysis, we investigated the association between midazolam premedication and a composite of other postoperative complications. Several sensitivity analyses were performed using similar regression models.

MAIN RESULTS

In total, 1973 patients were analyzed (median age 75 years, 47% women, 50% ASA score ≥ 3, 32% high risk surgery). The overall incidence of postoperative delirium was 15.3% (302/1973). Midazolam premedication was administered to 782 (40%) patients (median [IQR] dose 2 [1,2] mg). After adjustment for potential confounding variables, midazolam premedication was not associated with increased odds of postoperative delirium, with adjusted odds ratio of 1.09 (95% confidence interval 0.82-1.45; P = 0.538). Midazolam premedication was also not associated with the composite of other postoperative complications. Furthermore, no association was found between midazolam premedication and postoperative delirium in any of the sensitivity analyses preformed.

CONCLUSIONS

Our results suggest that low doses of midazolam can be safely used to pre-medicate elective surgical patients 70 years or older before non-cardiac surgery, without significant effect on the risk of developing postoperative delirium.

Parenteral nutrition-related complications in older patients with acute intestinal failure: A descriptive cohort study

INTRODUCTION

Reported outcomes for parenteral nutrition (PN)-related complications in older adult patients with acute intestinal failure who are receiving PN in the acute hospital setting are limited. Our study aims to compare PN-related complications between older and younger adult patients.

METHODS

A retrospective descriptive study of inpatients who were administered PN from January 1, 2019, to December 31, 2019, was performed. Patients were categorized into older (≥65 years old) and younger (<65 years old) adult groups.

RESULTS

Two hundred thirty-five patients were included. There were 103 patients in the older adult group (mean age: 73.9 [SD: 6.9] years) and 132 patients in the younger adult group (mean age: 52.4 [SD: 12.5] years). There was a significantly higher Charlson Comorbidity Index score and lower Karnofsky score in the older adult group. The older adult group received significantly lower total energy (20.8 [SD: 7.8] vs 22.8 [SD: 6.3] kcal/kg/day), dextrose (3.1 [SD: 1.4] vs 3.6 [SD: 1.4] g/kg/day), and protein (1.1 [SD: 0.4] vs 1.2 [SD: 0.3] g/kg/day) than the younger group received. The mean length of stay was significantly shorter in the older adult group (35.9 [SD: 21.3] vs 59.8 [SD: 55.3]; P < 0.05). There was no significant difference in PN-related complications and clinical outcomes (catheter-related bloodstream infections, hypoglycemia or hyperglycemia, fluid overload, or inpatient mortality) between the two groups.

CONCLUSION

Despite more comorbidities in the older adult, the usage of PN in older adult patients with acute intestinal failure was associated with neither an increased rate of PN-related complications nor worse clinical outcomes when compared with that of younger patients.

Peri-operative decisions about cardiopulmonary resuscitation among adults as reported to the 7th National Audit Project of the Royal College of Anaesthetists

Current guidance recommends that, in most circumstances, cardiopulmonary resuscitation should be attempted when cardiac arrest occurs during anaesthesia, and when a patient has a pre-existing 'do not attempt cardiopulmonary resuscitation' recommendation, this should be suspended. How this guidance is translated into everyday clinical practice in the UK is currently unknown. Here, as part of the 7th National Audit Project of the Royal College of Anaesthetists, we have: assessed the rates of pre-operative 'do not attempt cardiopulmonary resuscitation' recommendations via an activity survey of all cases undertaken by anaesthetists over four days in each participating site; and analysed our one-year case registry of peri-operative cardiac arrests to understand the rates of cardiac arrest in patients who had 'do not attempt cardiopulmonary resuscitation' decisions pre-operatively. In the activity survey, among 20,717 adults (aged > 18 y) undergoing surgery, 595 (3%) had a 'do not attempt cardiopulmonary resuscitation' recommendation pre-operatively, of which less than a third (175, 29%) were suspended. Of the 881 peri-operative cardiac arrest reports, 54 (6%) patients had a 'do not attempt cardiopulmonary resuscitation' recommendation made pre-operatively and of these 38 (70%) had a clinical frailty scale score ≥ 5. Just under half (25, 46%) of these 'do not attempt cardiopulmonary resuscitation' recommendations were formally suspended at the time of anaesthesia and surgery. One in five of these patients with a 'do not attempt cardiopulmonary resuscitation' recommendation who had a cardiac arrest survived to leave hospital and of the seven patients with documented modified Rankin Scale scores before and after cardiac arrest, four remained the same and three had worse scores. Very few patients who had a pre-existing 'do not attempt cardiopulmonary resuscitation' recommendation had a peri-operative cardiac arrest, and when cardiac arrest did occur, return of spontaneous circulation was achieved in 57%, although > 50% of these patients subsequently died before discharge from hospital.

Relevance of sarcopenia in elderly patients undergoing surgery for oral squamous cell carcinoma

In the elderly population there is increasing evidence that frailty predicts adverse outcomes better than chronological age. Sarcopenia is an important component of frailty. This study aimed to establish the relevance of sarcopenia in elderly patients with oral squamous cell carcinoma (OSCC) undergoing surgery. This retrospective, single-centre, cohort study included patients over the age of 75 years who were diagnosed with OSCC between 2007 and 2016. Cross-sectional imaging of the neck was used to predict the Skeletal Muscle Index (SMI) using validated equations. Based on established thresholds, patients were categorised as having either a normal or low SMI, indicative of sarcopenia. Sixty-nine patients met the inclusion criteria. Patients with a low SMI had a longer length of stay (16.9 days vs 9.8 days, p = 0.030); they had more severe complications, defined as Clavien-Dindo grade IIIb or higher (17.6% vs 4.0%, p = 0.042); and their mean Comprehensive Complication Index (CCI) was also higher (14.1 vs 4.7, p = 0.051). Furthermore, 2/34 patients in the low SMI group died within 30 days of surgery compared with none in the normal SMI group (5.9% vs 0%, p = 0.503). Whilst patients with a low SMI who underwent surgery had lower five-year overall survival, the difference was not statistically significant. This study shows that sarcopenia negatively influences surgical outcomes in elderly patients. Routine measurement of SMI could be an indication for a comprehensive geriatric assessment (CGA).

Dexmedetomidine nasal administration improves perioperative sleep quality and neurocognitive deficits in elderly patients undergoing general anesthesia

OBJECTIVE

To investigate the improvement of perioperative sleep quality and neurocognitive impairment in elderly patients under general anesthesia by nasal administration of dexmedetomidine.

METHODS

One hundred and twenty patients admitted to our hospital for various laparoscopic elective gynecological surgeries lasting more than 1 h under general anesthesia from July 2021 to March 2023 were selected. All subjects were divided into 3 groups according to the random number table method. From 21:00 to 21:30 every night from one day before to 5 days after surgery, group A was given alprazolam 0.4 mg orally; group B was given dexmedetomidine 1.5ug/kg nasal drip; group C was given saline nasal drip. All subjects were observed for general information, sleep quality, postoperative cognitive function, anxiety status, sleep quality, adverse effects and complication occurrence.

RESULTS

The difference in general information between the three groups was not statistically significant, P > 0.05; the sleep quality scores of the three groups on admission were not statistically significant, P > 0.05. At the Preoperative 1d, postoperative 1d, 3d and 5d, the RCSQ scores of the subjects in group A and group B were higher than those in groups C, and with the postoperative RCSQ scores of subjects in group B were higher as the time increased; the assessment of anxiety status in the three groups 1d before surgery was not statistically significant, P > 0.05. The cognitive function scores of subjects in the three groups were not statistically significant in the preoperative 1d, P > 0.05. The postoperative 1d (24.63 ± 2.23), 3d (25.83 ± 2.53), and 5d (26.15 ± 2.01) scores of the subjects in group B were higher than those in groups A and C (P < 0.05), and the subjects in group B had better recovery of postoperative cognitive function with increasing time; the occurrence of postoperative delirium (POD) in group B (12.5%) were lower on postoperative 5d than those in groups A (37.5%) and C (32.5%) (P < 0.05). There was no statistical significance in the evaluation of anxiety state of the three groups on the first day before operation (P > 0.05). The scores in group B were lower than those in group C on the postoperative 1d, 3d, 5 d (P < 0.05). The overall incidence of adverse reactions and complications in subjects in group B was 17.5% significantly lower than that in groups A and C (P < 0.05).

CONCLUSION

Dexmedetomidine can effectively improve the sleep disorder of elderly general anesthesia patients, reduce the damage to their neurocognitive function and the occurrence of POD, effectively reduce the anxiety of patients and the occurrence of adverse reactions and complications, and has better sedative, improve postoperative cognitive function and anti-anxiety effects, with a high drug safety, worthy of clinical application and promotion.

To Be Frail or Not to Be Frail: This Is the Question-A Critical Narrative Review of Frailty

Many factors have contributed to rendering frailty an emerging, relevant, and very popular concept. First, many pandemics that have affected humanity in history, including COVID-19, most recently, have had more severe effects on frail people compared to non-frail ones. Second, the increase in human life expectancy observed in many developed countries, including Italy has led to a rise in the percentage of the older population that is more likely to be frail, which is why frailty is much a more common concern among geriatricians compared to other the various health-care professionals. Third, the stratification of people according to the occurrence and the degree of frailty allows healthcare decision makers to adequately plan for the allocation of available human professional and economic resources. Since frailty is considered to be fully preventable, there are relevant consequences in terms of potential benefits both in terms of the clinical outcome and healthcare costs. Frailty is becoming a popular, pervasive, and almost omnipresent concept in many different contexts, including clinical medicine, physical health, lifestyle behavior, mental health, health policy, and socio-economic planning sciences. The emergence of the new "science of frailty" has been recently acknowledged. However, there is still debate on the exact definition of frailty, the pathogenic mechanisms involved, the most appropriate method to assess frailty, and consequently, who should be considered frail. This narrative review aims to analyze frailty from many different aspects and points of view, with a special focus on the proposed pathogenic mechanisms, the various factors that have been considered in the assessment of frailty, and the emerging role of biomarkers in the early recognition of frailty, particularly on the role of mitochondria. According to the extensive literature on this topic, it is clear that frailty is a very complex syndrome, involving many different domains and affecting multiple physiological systems. Therefore, its management should be directed towards a comprehensive and multifaceted holistic approach and a personalized intervention strategy to slow down its progression or even to completely reverse the course of this condition.

Dental Surgical Activity in Hospitals during COVID-19: A Nationwide Observational Cohort Study

INTRODUCTION

The number of surgical extractions performed in hospitals in England remains unclear. This study reports the volume of surgical extractions conducted in hospitals and change in activity during the COVID-19 pandemic.

METHODS

We conducted a nationwide observational cohort study using Hospital Episode Statistics (HES) in England for patients undergoing surgical removal of a tooth (defined using OPSC-4 code F09) between April 1, 2015, and December 31, 2020. Procedures were stratified by age, gender, and urgency (elective or nonelective), reported using descriptive statistics, number, and percentage. We conducted post hoc modeling to predict surgical activity to December 2023. In addition, we contrasted this with aggregate national data on simple dental extraction procedures and drainage of dental abscesses in hospital as well as dental activity in general practice.

RESULTS

We identified a total of 569,938 episodes for the surgical removal of a tooth (females 57%). Of these, 493,056/569,938 (87%) were for adults and 76,882/569,938 (13%) children ≤18 years. Surgical extractions were most frequent in adult females. Elective cases accounted for 96% (n = 548,805/569,938) of procedures. The median number of procedures carried out per quarter was 27,256, dropping to 12,003 during the COVID-19 pandemic, representing a 56% reduction in activity. This amounted to around 61,058 cancelled procedures. Modeling predicts that this activity has not returned to prepandemic levels.

CONCLUSIONS

The number of surgical extractions taking place in hospitals during the pandemic fell by 56%. The true impact of this reduction is unknown, but delayed treatment increases the risk of complications, including life-threatening infections.

KNOWLEDGE TRANSFER STATEMENT

The result of this study provides an evidence-based overview of the trends relating to surgical extractions of teeth in England taking place in hospitals. This information can be used to inform service and workforce planning to meet the needs of patients requiring surgical extractions. The data also provide an insight into the oral health needs of the population in England.

Cystatin C or creatinine for pre-operative assessment of kidney function and risk of post-operative acute kidney injury: a secondary analysis of the METS cohort study

Background

Post-operative acute kidney injury (PO-AKI) is a common surgical complication consistently associated with subsequent morbidity and mortality. Prior kidney dysfunction is a major risk factor for PO-AKI, however it is unclear whether serum creatinine, the conventional kidney function marker, is optimal in this population. Serum cystatin C is a kidney function marker less affected by body composition and might provide better prognostic information in surgical patients.

Methods

This was a pre-defined, secondary analysis of a multi-centre prospective cohort study of pre-operative functional capacity. Participants were aged ≥40 years, undergoing non-cardiac surgery. We assessed the association of pre-operative estimated glomerular filtration rate (eGFR) calculated using both serum creatinine and serum cystatin C with PO-AKI within 3 days after surgery, defined by KDIGO creatinine changes. The adjusted analysis accounted for established AKI risk factors.

Results

A total of 1347 participants were included (median age 65 years, interquartile range 56-71), of whom 775 (58%) were male. A total of 82/1347 (6%) patients developed PO-AKI. These patients were older, had higher prevalence of cardiovascular disease and related medication, were more likely to have intra-abdominal procedures, had more intraoperative transfusion, and were more likely to be dead at 1 year after surgery 6/82 (7.3%) vs 33/1265 (2.7%) (P = .038). Pre-operative eGFR was lower in AKI than non-AKI patients using both creatinine and cystatin C. When both measurements were considered in a single age- and sex-adjusted model, eGFR-Cysc was strongly associated with PO-AKI, with increasing risk of AKI as eGFR-Cysc decreased below 90, while eGFR-Cr was no longer significantly associated.

Conclusions

Data from over 1000 prospectively recruited surgical patients confirms pre-operative kidney function as major risk factor for PO-AKI. Of the kidney function markers available, compared with creatinine, cystatin C had greater strength of association with PO-AKI and merits further assessment in pre-operative assessment of surgical risk.

Effect of prehabilitation on postoperative outcomes in the frail older people: A systematic review and meta-analysis

OBJECTIVE

The study investigates the impact of preoperative rehabilitation on the surgical prognosis of frail older patients.

METHOD

The effect sizes of all studies retrieved and included by the nine databases were analyzed and expressed as RR and WMD.

RESULTS

8 studies with 902 participants met the criteria for inclusion. A significant reduction in total complications (RR = 0.84, 95 % CI = 0.73 to 0.97, P = 0.021) and the 6MWT after surgery (WMD = 74.76, 95 % CI = 44.75 to 104.77, P = 0.000) was observed in the prehabilitation group. But it had no differences in mortality(RR = 1.89, 95 % CI = 0.75 to 4.72, P = 0.176), readmission rates(RR = 1.04, 95 % CI = 0.56 to 1.91, P = 0.906) and LOS(WMD = -0.24, 95 % CI = -1.00 to 0.52, P = 0.540).

CONCLUSIONS

Prehabilitation had positive effect on postoperative complications and functional recovery in frail older patients.

Study protocol for a national observational cohort investigating frailty, delirium and multimorbidity in older surgical patients: the third Sprint National Anaesthesia Project (SNAP 3)

INTRODUCTION

Older surgical patients are more likely to be living with frailty and multimorbidity and experience postoperative complications. The management of these conditions in the perioperative pathway is evolving. In order to support objective decision-making for patients, services and national guidance, accurate, contemporary data are needed to describe the impact and associations between frailty, multimorbidity and healthcare processes with patient and service-level outcomes.

METHODS AND ANALYSIS

The study is comprised of an observational cohort study of approximately 7500 patients; an organisational survey of perioperative services and a clinician survey of the unplanned, medical workload generated from older surgical patients. The cohort will consist of patients who are 60 years and older, undergoing a surgical procedure during a 5-day recruitment period in participating UK hospitals. Participants will be assessed for baseline frailty and multimorbidity; postoperative morbidity including delirium; and quality of life. Data linkage will provide additional details about individuals, their admission and mortality.The study's primary outcome is length of stay, other outcome measures include incidence of postoperative morbidity and delirium; readmission, mortality and quality of life. The cohort's incidence of frailty, multimorbidity and delirium will be estimated using 95% CIs. Their relationships with outcome measures will be examined using unadjusted and adjusted multilevel regression analyses. Choice of covariates in the adjusted models will be prespecified, based on directed acyclic graphs.A parallel study is planned to take place in Australia in 2022.

ETHICS AND DISSEMINATION

The study has received approval from the Scotland A Research Ethics Committee and Wales Research Ethics Committee 7.This work hopes to influence the development of services and guidelines. We will publish our findings in peer-reviewed journals and provide summary documents to our participants, sites, healthcare policy-makers and the public.

TRIAL REGISTRATION NUMBER

ISRCTN67043129.

A comprehensive analysis of the triad of frailty, aging, and obesity in spine surgery: the risk analysis index predicted 30-day mortality with superior discrimination

BACKGROUND CONTEXT

The United States has experienced substantial shifts in its population dynamics due to an aging population and increasing obesity rates. Nonetheless, there is limited data about the interplay between the triad of frailty, aging, and obesity.

PURPOSE

To investigate discriminative thresholds and independent associations of the Risk Analysis Index (RAI), Modified Frailty Index-5 (mFI-5), and greater patient age.

STUDY DESIGN

An observational retrospective cohort study.

PATIENT SAMPLE

We analyzed 49,754 spine surgery patients from the American College of Surgeons National Surgical Quality Improvement Program database from 2012 to 2020.

OUTCOME MEASURE

A total of 30-day postoperative mortality.

METHODS

Using receiver operating characteristic (ROC) and multivariable (odds ratios [OR] and 95% confidence intervals [CI]) analyses, we compared the discriminative thresholds and independent associations of RAI, mFI-5, and greater patient age in elderly obese patients who underwent spine surgery.

RESULTS

There were 49,754 spine surgery patients, with a median age of 71 years (IQR: 68-75), largely white (82.6%) and male (51.9%). The ROC analysis for 30-day postoperative mortality demonstrated superior discrimination for RAI (C-statistic 0.779, 95%CI 0.54-0.805) compared to mFI-5 (C-statistic 0.623, 95% CI 0.594-0.651) and greater patient age (C-statistic 0.627, 95% CI 0.598-0.656). Multivariable analyses revealed a dose-dependent association and a larger effect magnitude for RAI: frail patients OR: 19.52 (95% CI 18.29-20.82) and very frail patients OR: 65.81 (95% CI 62.32-69.50). A similar trend was observed in the interaction evaluating RAI-age-obesity (p<.001).

CONCLUSION

Our study highlights a strong association between frailty and 30-day postoperative mortality in elderly obese spine patients, revealing a dose-dependent relationship. The RAI has superior discrimination than the mFI-5 and greater patient age in predicting 30-day postoperative mortality after spine surgery. Using the RAI in preoperative assessments may improve outcomes and help healthcare providers effectively communicate accurate surgical risks and potential benefits, set realistic recovery expectations, and enhances patient satisfaction.

Epidemiology of surgery associated acute kidney injury (EPIS-AKI): a prospective international observational multi-center clinical study

PURPOSE

The incidence, patient features, risk factors and outcomes of surgery-associated postoperative acute kidney injury (PO-AKI) across different countries and health care systems is unclear.

METHODS

We conducted an international prospective, observational, multi-center study in 30 countries in patients undergoing major surgery (> 2-h duration and postoperative intensive care unit (ICU) or high dependency unit admission). The primary endpoint was the occurrence of PO-AKI within 72 h of surgery defined by the Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Secondary endpoints included PO-AKI severity and duration, use of renal replacement therapy (RRT), mortality, and ICU and hospital length of stay.

RESULTS

We studied 10,568 patients and 1945 (18.4%) developed PO-AKI (1236 (63.5%) KDIGO stage 1500 (25.7%) KDIGO stage 2209 (10.7%) KDIGO stage 3). In 33.8% PO-AKI was persistent, and 170/1945 (8.7%) of patients with PO-AKI received RRT in the ICU. Patients with PO-AKI had greater ICU (6.3% vs. 0.7%) and hospital (8.6% vs. 1.4%) mortality, and longer ICU (median 2 (Q1-Q3, 1-3) days vs. 3 (Q1-Q3, 1-6) days) and hospital length of stay (median 14 (Q1-Q3, 9-24) days vs. 10 (Q1-Q3, 7-17) days). Risk factors for PO-AKI included older age, comorbidities (hypertension, diabetes, chronic kidney disease), type, duration and urgency of surgery as well as intraoperative vasopressors, and aminoglycosides administration.

CONCLUSION

In a comprehensive multinational study, approximately one in five patients develop PO-AKI after major surgery. Increasing severity of PO-AKI is associated with a progressive increase in adverse outcomes. Our findings indicate that PO-AKI represents a significant burden for health care worldwide.

Mismatch of populations between randomised controlled trials of perioperative interventions in major abdominal surgery and current clinical practice

BACKGROUND

Demographics of patients undergoing major abdominal surgery are changing. External validity of relevant RCTs may be limited by participants not resembling patients encountered in clinical practice. We aimed to characterise differences in age, weight, BMI, and ASA grade between participants in perioperative trials in major abdominal surgery and patients in a reference real-world clinical practice sample. The secondary aim was to investigate whether time since trial publication was associated with increasing mismatch between these groups.

METHODS

MEDLINE and Embase were searched for multicentre RCTs from inception to September 2022. Studies of perioperative interventions in adults were included. Studies that limited enrolment based on age, weight, BMI, or ASA status were excluded. We compared trial cohort age, weight, BMI, and ASA distribution to those of patients undergoing major abdominal surgery at our tertiary referral hospital during September 2021 to September 2022. We used a local, single-institution reference sample to reflect the reality of clinical practice (i.e. patients treated by a clinician in their own hospital, rather than averaged nationally). Mismatch was defined using comparison of summary characteristics and ad hoc criteria based on differences relevant to predicted mortality risk after surgery.

RESULTS

One-hundred and six trials (44,499 participants) were compared to a reference cohort of 2792 clinical practice patients. Trials were published a median (IQR [range]) 13.4 (5-20 [0-35]) years ago. A total of 94.3% of trials were mismatched on at least one characteristic (age, weight, BMI, ASA). Recruitment of ASA 3 + participants in trials increased over time, and recruitment of ASA 1 participants decreased over time (Spearman's Rho 0.58 and - 0.44, respectively).

CONCLUSIONS

Patients encountered in our current local clinical practice are significantly different from those in our defined set of perioperative RCTs. Older trials recruit more low-risk than high-risk participants-trials may thus 'expire' over time. These trials may not be generalisable to current patients undergoing major abdominal surgery, and meta-analyses or guidelines incorporating these trials may therefore be similarly non-applicable. Comparison to local, rather than national cohorts, is important for meaningful on-the-ground evidence-based decision-making.

Perioperative Anxiety and Depression in Older Adults: Epidemiology and Treatment

The intervals before and after major surgery is a high-risk period for older adults; in this setting, anxiety and depression are common and serious problems. We comprehensively reviewed current evidence on perioperative anxiety and depression in older adults, focusing on epidemiology, impact, correlates, medication risks, and treatment. Principles of perioperative mental healthcare are proposed based on the findings. Prevalence estimates of clinically significant anxiety and depression range from 5% to 45% for anxiety and 6% to 52% for depression, depending on surgical populations and measurement tools. Anxiety and depression may increase risk for surgical complications and reduce patient participation during rehabilitation. Medical comorbidities, pain, insomnia, cognitive impairment, and delirium are common co-occurring problems. Concomitant uses of central nervous system acting medications (benzodiazepines, anticholinergics, and opioids) amplify the risks of delirium and falls. Based on these findings, we propose that anxiety and depression care should be part of perioperative management in older adults; components include education, psychological support, opioid-sparing pain management, sleep management, deprescribing central nervous system active medications, and continuation and optimization of existing antidepressants. More research is needed to test and improve these care strategies.

Developing the workforce to deliver perioperative medicine for older people undergoing surgery: a transdisciplinary education programme

Patients who are older, frail and medically complex are increasingly presenting for elective and emergency surgical interventions. Comprehensive Geriatric Assessment (CGA) and optimisation methodology improve morbidity and mortality in older surgical patients. However, there is a need to develop an extended and flexible workforce to provide patient-centred quality perioperative care and to simultaneously tackle the growing backlog of planned surgery following the Coronavirus 2019 (COVID-19) pandemic. At Guy's and St Thomas' NHS Foundation Trust, Perioperative Medicine for Older People (POPS) delivers a transdisciplinary education programme for foundation doctors, specialty registrars and advanced clinical practitioners to develop a blended team with shared capabilities and goals in perioperative care. This case study outlines the framework of how the education programme was developed and its evaluation, and the ongoing work of POPS to disseminate knowledge and promote national innovation and collaboration.

Association of preoperative anaesthesia consultation prior to elective noncardiac surgery with patient and health system outcomes: a population-based study

BACKGROUND

Surgical volumes and use of preoperative anaesthesia consultations are increasing. However, contemporary data estimating the association between preoperative anaesthesia consultation and patient (days alive and at home [DAH30], mortality) and system (costs, length of stay, and readmissions) outcomes are not available.

METHODS

We conducted a population-based comparative effectiveness study using linked health administrative data among patients aged ≥40 yr who underwent intermediate-risk to high-risk elective, inpatient, noncardiac surgery in Ontario, Canada (2009-17). Our primary outcome was DAH30. Secondary outcomes included DAH90, 30-day and 1-yr mortality, 30-day health system costs, length of index admission, and 30-day readmissions. Propensity score overlap weights were used to adjust for confounders. Prespecified effect modifier analyses focused on high-risk subgroups.

RESULTS

Among 364 149 patients, 274 365 (75.3%) received a preoperative anaesthesia consultation. No adjusted association was found (22.5 days vs 22.5 days; adjusted ratio of means 1.00, 95% CI 1.00-1.00) between consultation and DAH30 in the full population. We identified significant effect modification (significantly more DAH30) among patients with ischaemic heart disease, ASA physical status ≥4, frailty index score ≥0.21, and who underwent vascular surgery. Secondary outcomes were associated with preoperative consultation, including greater DAH90, decreased length of stay, lower 30-day and 1-yr mortality, and reduced 30-day costs.

CONCLUSIONS

Preoperative anaesthesia consultation was not associated with greater DAH30 across the overall study population. However, important potential benefits were observed among high-risk subgroups. Research is needed to identify optimal patient populations and consultation processes.

EEG microstate quantifiers and state space descriptors during anaesthesia in patients with postoperative delirium: a descriptive analysis

Postoperative delirium is a serious sequela of surgery and surgery-related anaesthesia. One recommended method to prevent postoperative delirium is using bi-frontal EEG recording. The single, processed index of depth of anaesthesia allows the anaesthetist to avoid episodes of suppression EEG and excessively deep anaesthesia. The study data presented here were based on multichannel (19 channels) EEG recordings during anaesthesia. This enabled the analysis of various parameters of global electrical brain activity. These parameters were used to compare microstate topographies under anaesthesia with those in healthy volunteers and to analyse changes in microstate quantifiers and EEG global state space descriptors with increasing exposure to anaesthesia. Seventy-three patients from the Surgery Depth of Anaesthesia and Cognitive Outcome study (SRCTN 36437985) received intraoperative multichannel EEG recordings. Altogether, 720 min of artefact-free EEG data, including 210 min (29.2%) of suppression EEG, were analysed. EEG microstate topographies, microstate quantifiers (duration, frequency of occurrence and global field power) and the state space descriptors sigma (overall EEG power), phi (generalized frequency) and omega (number of uncorrelated brain processes) were evaluated as a function of duration of exposure to anaesthesia, suppression EEG and subsequent development of postoperative delirium. The major analyses involved covariate-adjusted linear mixed-effects models. The older (71 ± 7 years), predominantly male (60%) patients received a median exposure of 210 (range: 75-675) min of anaesthesia. During seven postoperative days, 21 patients (29%) developed postoperative delirium. Microstate topographies under anaesthesia resembled topographies from healthy and much younger awake persons. With increasing duration of exposure to anaesthesia, single microstate quantifiers progressed differently in suppression or non-suppression EEG and in patients with or without subsequent postoperative delirium. The most pronounced changes occurred during enduring suppression EEG in patients with subsequent postoperative delirium: duration and frequency of occurrence of microstates C and D progressed in opposite directions, and the state space descriptors showed a pattern of declining uncorrelated brain processes (omega) combined with increasing EEG variance (sigma). With increasing exposure to general anaesthesia, multiple changes in the dynamics of microstates and global EEG parameters occurred. These changes varied partly between suppression and non-suppression EEG and between patients with or without subsequent postoperative delirium. Ongoing suppression EEG in patients with subsequent postoperative delirium was associated with reduced network complexity in combination with increased overall EEG power. Additionally, marked changes in quantifiers in microstate C and in microstate D occurred. These putatively adverse intraoperative trajectories in global electrical brain activity may be seen as preceding and ultimately predicting postoperative delirium.

Postoperative Critical Care Admission Was Not Associated with Improved Postoperative Outcomes in Elective Colorectal Surgery: Secondary Analysis Of POWER Trial

BACKGROUND

The efficacy of routine admission of high-risk patients to a critical care unit after surgery is not clear. The aim of our study was to investigate the association between critical care admission after scheduled colorectal surgery and postoperative complications, 30-day mortality, and length of stay in hospital.

METHODS

A pre-defined secondary substudy of POWER study was performed. POWER study was a prospective multicenter observational study of patients undergoing elective primary colorectal surgery during a single period of two months of recruitment between September and December 2017.

RESULTS

A total of 2084 patients from 80 Spanish hospitals were included, of which 722 (34.6%) were admitted to critical care unit (CCU) after elective surgery. After adjusting for confounding factors in the multivariate analysis, postoperative CCU admission was independently associated with a higher incidence of moderate-to-severe postoperative complications (adjusted OR 1.951, 95% CI 1.570, 2.425; p < 0.001). Regarding secondary outcomes, postoperative critical care admission was independently associated with higher 30-day mortality (adjusted OR 6.736; 95% CI 2.507, 18.101; p < 0.001) and independently associated with an increased hospital length of stay (adjusted OR 1.143, 95% CI 1.112, 1.175; p < 0.001).

CONCLUSIONS

Direct admission to CCU after scheduled colorectal surgery was not associated with a reduction in moderate-to-severe postoperative complications.

Staphylococcus aureus surgical site infection rates in 5 European countries

OBJECTIVE

To determine the overall and procedure-specific incidence of surgical site infections (SSI) caused by Staphylococcus aureus (S. aureus) as well as risk factors for such across all surgical disciplines in Europe.

METHODS

This is a retrospective cohort of patients with surgical procedures performed at 14 European centres in 2016, with a nested case-control analysis. S. aureus SSI were identified by a semi-automated crossmatching bacteriological and electronic health record data. Within each surgical procedure, cases and controls were matched using optimal propensity score matching.

RESULTS

A total of 764 of 178 902 patients had S. aureus SSI (0.4%), with 86.0% of these caused by methicillin susceptible and 14% by resistant pathogens. Mean S. aureus SSI incidence was similar for all surgical specialties, while varying by procedure.

CONCLUSIONS

This large procedure-independent study of S. aureus SSI proves a low overall infection rate of 0.4% in this cohort. It provides proof of principle for a semi-automated approach to utilize big data in epidemiological studies of healthcare-associated infections. Trials registration The study was registered at clinicaltrials.gov under NCT03353532 (11/2017).

Clinicians' adherence to guidelines for the preoperative management of direct oral anticoagulants in a tertiary hospital: a retrospective study

INTRODUCTION

Despite clear, relatively easy-to-use guidance, many clinicians find the preoperative management of direct oral anticoagulants (DOACs) challenging. Inappropriate management can delay procedures and lead to haemorrhagic or thromboembolic complications. We aimed to describe preoperative management practices regarding DOACs in a tertiary hospital and clinicians' adherence to in-house recommendations.

METHOD

We included all patients being treated with DOACs who underwent elective surgery in 2019 and 2020 (n = 337). In-house recommendations for perioperative management were largely comparable to the 2022 American College of Chest Physicians guidelines.

RESULTS

Typical patients were older adults with multiple comorbidities and high thrombotic risk stratification scores, and 65.6% (n = 221) had not undergone recommended preoperative anticoagulation management protocols. Patients operated on using local anaesthesia (adjusted OR = 0.30, 95%CI 0.14-0.66; p < 0.01) were less likely to have been treated following institutional recommendations, but no association between their procedure's bleeding risk and adherence was found. Clinicians' failures to adhere to recommendations mostly involved late or non-indicated interruptions of anticoagulation treatment (n = 89, 26.4%) or inappropriate heparin bridging (n = 54, 16.0%). Forty-five (13.3%) procedures had to be postponed. Incorrect preoperative anticoagulation management was directly responsible for 12/45 postponements (26.7% of postponements).

CONCLUSION

This study highlights clinicians' low adherence rates to institutional recommendations for patients treated with DOACs scheduled for elective surgery in a tertiary hospital centre. To the best of our knowledge, this is the first clinical study addressing the issue of clinicians' adherence to guidelines for the preoperative management of DOACs. Going beyond the issue of whether clinicians are knowledgeable about guidelines or have them available, this study questions how generalisable guidelines are in a tertiary hospital managing many highly polymorbid patients. Further studies should identify the causes of poor adherence.

Does surgery cause anxiety, stress and fear in geriatric patients?

BACKGROUND

Because of physiological changes in geriatric patients, their surgical process differs from that of young adults. In this regard, the perioperative period is an extremely risky time for geriatric patients. The present study examined preoperative fear, anxiety, and perceived stress levels as well as the factors affecting them in elderly patients prior to surgical intervention.

METHODS

This study adopted a cross-sectional descriptive design. The study sample consisted of geriatric patients (n = 407) scheduled for elective laparoscopic cholecystectomy in a research and training hospital in northeast Turkey. Data were collected by the researchers using the personal information form, Perceived Stress Scale (PSS-10), Surgical Fear Questionnaire (SFQ) and Anxiety Specific to Surgery Questionnaire (ASSQ). In the data analysis, descriptive statistics, the t-test in independent groups, one-way analysis of variance (ANOVA), correlation analysis and Bonferroni tests for post hoc analyses were used.

RESULTS

On the PSS-10, the mean score was higher for the 75-and-older age group, single patients, patients with a disease requiring medication, and those who had previously undergone surgery (P < 0.05). On the ASSQ, the mean score was lower for patients aged 65-69, university graduates, patients without children, and those without a disease requiring medication (P < 0.05). On the SFQ, the mean score was higher for the 75-and-older age group, primary school graduates, and single patients (P < 0.05).

CONCLUSION

It was determined that being single, having a chronic disability, and advancing age had an effect on the patients' surgery-specific anxiety, perceived stress, and fear of surgery. Long-standing chronic diseases can negatively affect both stress and anxiety levels of individuals.

Long-term healthcare use after postoperative complications: an analysis of linked primary and secondary care routine data

Background

Postoperative complications are associated with reduced long-term survival. We characterise healthcare use changes after sentinel postoperative complications.

Methods

We linked primary and secondary care records of patients undergoing elective surgery at four East London hospitals (2012-7) with at least 90 days follow-up. Complication codes (wound infection, urinary tract infection, pneumonia, new stroke, and new myocardial infarction) recorded within 90 days of surgery were identified from primary or secondary care. Outcomes were change in healthcare contact days in the 2 yr before and after surgery, and 2 yr mortality. We report rate ratios (RaR) with 95% confidence intervals and adjusted for baseline healthcare use and confounders using negative binomial regression.

Results

We included 49 913 patients (median age 49 yr [inter-quartile range {IQR}: 34-64]), 27 958 (56.0%) were female. Amongst 3883 (7.8%) patients with complications (median age 58 [IQR: 43-72]), there were 18.4 days per year in contact with healthcare before surgery and 25.3 days after surgery (RaR: 1.38 [1.37-1.39]). Patients without complications (median age 48 [IQR: 33-63]) had 12.3 days per year in contact with healthcare before surgery and 14.0 days after surgery (RaR: 1.14 [1.14-1.15]). The adjusted incidence rate ratio of days in contact with healthcare associated with complications was 1.67 (1.49-1.87). More patients (391; 10.1%) with complications died within 2 yr than those without (1428; 3.1%).

Conclusions

Patients with postoperative complications are older with greater healthcare use before surgery. However, their absolute and relative increases in healthcare use after surgery are greater than patients without complications.

The surgical patient of yesterday, today, and tomorrow-a time-trend analysis based on a cohort of 8.7 million surgical patients

BACKGROUND

Global healthcare delivery is challenged by the aging population and the increase in obesity and type 2 diabetes. The extent to which such trends affect the cohort of patients the authors surgically operate on remains to be elucidated. Comprising of 8.7 million surgical patients, the American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) database can be analyzed to investigate the echo of general population dynamics and forecast future trends.

MATERIAL AND METHODS

The authors reviewed the ACS-NSQIP database (2008-2020) in its entirety, extracting patient age, BMI, and diabetes prevalence. Based on these data, the authors forecasted future trends up to 2030 using a drift model.

RESULTS

During the review period, median age increased by 3 years, and median BMI by 0.9 kg/m2. The proportion of patients with overweight, obesity class I, and class II rates increased. The prevalence of diabetes rose between 2008 (14.9%) and 2020 (15.3%). The authors forecast the median age in 2030 to reach 61.5 years and median BMI to climb to 29.8 kg/m2. Concerningly, in 2030, eight of ten surgical patients are projected to have a BMI above normal. Diabetes prevalence is projected to rise to 15.6% over the next decade.

CONCLUSION

General population trends echo in the field of surgery, with the surgical cohort aging at an alarmingly rapid rate and increasingly suffering from obesity and diabetes. These trends show no sign of abating without dedicated efforts and call for urgent measures and fundamental re-structuring for improved future surgical care.

The future of ambulatory surgery for geriatric patients

The elderly segment of the population is growing rapidly worldwide. Older patients comprise a disproportionate percentage of the surgical caseload. Physiological changes are inevitable with aging; some may impact a patient's response to anesthesia and surgery. Careful evaluation of an elderly patient preoperatively is vital to proper patient selection for ambulatory surgeries, particularly for complex and lengthy procedures. Cognitive issues, frailty, and geriatric syndromes make a patient vulnerable and sometimes unsuitable for certain ambulatory procedures. Preoperative planning and interventions may improve outcomes for the elderly patient undergoing ambulatory surgery.

Perioperative neurocognitive disorders

Perioperative neurocognitive disorders are a group of conditions characterised by changes in cognitive function, which affect older people after surgery and anaesthesia. Multicomponent interventions may reduce the impact of perioperative neurocognitive disorders on patients and healthcare systems.

Implementing a perioperative care of older people undergoing surgery (POPS) service: findings from a multi-site qualitative implementation study

BACKGROUND

The Perioperative care for Older People undergoing Surgery (POPS) service model is increasingly being implemented across care providers in the English and Welsh National Health Services.

OBJECTIVE

The study aimed to produce evidence regarding clinical leaders' activities to implement POPS across different service contexts and to produce generalisable recommendations for future implementation.

METHODS

A qualitative interview study was undertaken across six National Health Services hospitals with established POPS services. Interview participants were recruited on the basis of their direct involvement in the implementation and leadership of the service. Data collection involved semi-structured interviews with 26 people carried out between November 2022 and May 2023.

RESULTS

The implementation of POPS is often hampered by a lack of managerial and financial support, and apprehension amongst surgeons and anaesthetist about new ways of working. POPS leaders address these through five interconnected activities, each targeted at a combination of implementation factors. (i) Securing management and financial support. (ii) Professional engagement. (iii) Evidence building as a resource for demonstrating the clinical and operational benefits of POPS. (iv) Communication and engagement activities to promote and legitimise POPS to stakeholder groups. (v) Designated and distributed leadership to promote and coordinate implementation activities and to spread the service to new pathways.

CONCLUSIONS

Through a combination of activities POPS can be effectively implemented across different organisational contexts. Some aspects of these activities can be guided by shared resources and learning across sites, but others require adaption to local contextual barriers and drivers.

Optimizing Nutritional Status of Patients Prior to Major Surgical Intervention

In patients undergoing elective cardiovascular and thoracic surgery, malnutrition and the deterioration of nutritional status are associated with negative outcomes. Recognition of the contributory factors and the complications stemming from surgical stress is important for the prevention and management of these patients. We have reviewed the literature available and focused on the nutritional and metabolic aspects affecting surgical patients, with emphasis on the recommendations of enhanced recovery protocols. The implementation of enhanced recovery protocols and nutritional support guidelines focusing on the surgical patient as part of a multidisciplinary approach would improve the nutritional status of surgical patients at risk for negative outcomes.

Outcomes and complications of nonagenarians undergoing cardiac surgery: a scoping review protocol

INTRODUCTION

Continually rising life expectancy and a shift towards an ageing population are resulting in an increasing population of nonagenarians. By 2030, the global population of nonagenarians is expected to exceed 30 million. The incidence of symptomatic cardiac disease is reported to occur in 25% of those aged over 75 years. Therefore, the number of nonagenarians undergoing cardiac surgery is also expected to increase. A linear relationship between advanced age and surgical risk has previously been demonstrated; however, it is not yet known whether this knowledge extends to the perioperative course and mortality of nonagenarians undergoing cardiac surgery. This scoping review aims to review the literature, assess whether a deficiency exists in the published literature and potentially identify knowledge gaps to guide future efforts to improve the understanding of nonagenarians undergoing cardiac surgery.

METHODS AND ANALYSIS

Following the relevant aspects of the Preferred Reporting Items for Systematic Review and Meta-Analysis Extension for Scoping Review guidelines, electronic databases of MEDLINE, EMBASE and the Cochrane Library will be systematically searched, with additional reference tracking of eligible studies. Studies reporting the outcomes of nonagenarians undergoing open cardiac surgery or minimally invasive cardiac surgery requiring cardiopulmonary bypass will be included. Screening and data extraction will be performed by two reviewers independently. The data will be analysed and summarised descriptively with a narrative approach. Qualitative data that capture quality-of-life outcomes will be subjected to thematic analysis where feasible. Additionally, reporting results will highlight similarities and differences in nonagenarian selection for surgery.

ETHICS AND DISSEMINATION

Ethics approval was not required. The findings will be disseminated through professional networks, conference presentations and publications in scientific journals.

Modifiable risk factors for post-operative delirium in older adults undergoing major non-cardiac elective surgery: a multi-centre, trainee delivered observational cohort feasibility study and trainee survey

BACKGROUND

Post-operative delirium (POD) is an acute brain failure which may occur following major surgery, with serious implications for participants and caregivers. Evidence regarding optimal anaesthetic management for older participants at higher risk of POD is conflicting. We conducted a feasibility study of our protocol in 5 centres to guide sample size estimation and inform future recruitment strategies for a larger cohort study.

METHODS

Participants aged over 65 and scheduled for major surgery were recruited. They were assessed pre-operatively for delirium, cognitive impairment, depression, comorbidity, activity levels and alcohol use. Details of management during surgery, all medications and complications were recorded by a trainee-led research team. Participants were assessed for delirium in the immediate recovery period and then on post-operative days 1-4 using the 4 question attention test (4AT) with complications assessed at day 4 using the post-operative morbidity survey (POMS). Primary outcomes were the incident rates of POD. Secondary outcomes were number of eligible patients, recruitment rates and retention rates throughout the study, time required for data collection, preoperative risk factors assessment and daily postoperative delirium assessments. Also to assess the added value of employing the regional trainee research network (INCARNNET) to deliver the study. Specifically, what proportion of patient consent, data collection and post-operative testing is performed by anaesthesia trainees from this group, especially the success of weekend delirium assessment by trainees? A survey was completed at the end of the study by the trainees involved regarding their involvement in the study.

RESULTS

Ninety-five participants were recruited, of whom 93 completed the study. Overall, POD occurred in 9 patients. Of these, three were detected in recovery and six on post-op days 1-4. Median length of stay was 6 days. Recruitment rates were high in all but one site. 59 (62%) participants were consented by trainees and 189 (63%) of post op delirium assessments were performed by trainees. A total of six patients declined the study (in a follow up survey of trainees). Pre-existing cognitive impairment, depression and problem drinking were detected in 4(4.3%), 3(3.2%) and 5(5.37%) participants, respectively. Co-morbidity was common with 55(59%) in class three or four of the geriatric index of morbidity. Overall, from a total of 641 data points, levels of missing data were as follows, site A = 9.3%, B = 13.5%, C = 15.4%, D = 10.9%, E = 11.1% (data could not be completed retrospectively).

CONCLUSIONS

A multi-centre observational cohort study of delirium carried out by UK trainee anaesthetists is feasible. Patients are content to undergo day of surgery consent and multiple short questionnaires pre-operatively. Proposed data, especially pharmacological, should be carefully considered for their relevance to modifiable mechanisms that can lead to POD. Future research to enable prognostic modelling of POD should involve large scale cohort studies of enriched populations to capture a higher POD incidence. POD remains a common complication in older persons undergoing major surgery in the UK and studies of interventions are urgently needed.

TRIAL REGISTRATION

All methods were carried out in accordance with relevant guidelines and regulations. The study was retrospectively registered with ISRCTN94663125 on 07/02/2018.