Candidate Kidney Protective Strategies for Patients Undergoing Major Abdominal Surgery: A Secondary Analysis of the RELIEF Trial Cohort

BACKGROUND

Acute kidney injury (AKI) is common after major abdominal surgery. Selection of candidate kidney protective strategies for testing in large trials should be based on robust preliminary evidence.

METHODS

A secondary analysis of the Restrictive versus Liberal Fluid Therapy in Major Abdominal Surgery (RELIEF) trial was conducted in adult patients undergoing major abdominal surgery and randomly assigned to a restrictive or liberal perioperative fluid regimen. The primary outcome was maximum AKI stage before hospital discharge. Two multivariable ordinal regression models were developed to test the primary hypothesis that modifiable risk factors associated with increased maximum stage of postoperative AKI could be identified. Each model used a separate approach to variable selection to assess the sensitivity of the findings to modeling approach. For model 1, variable selection was informed by investigator opinion; for model 2, the Least Absolute Shrinkage and Selection Operator (LASSO) technique was used to develop a data-driven model from available variables.

RESULTS

Of 2,444 patients analyzed, stage 1, 2, and 3 AKI occurred in 223 (9.1%), 59 (2.4%), and 36 (1.5%) patients, respectively. In multivariable modeling by model 1, administration of a nonsteroidal anti-inflammatory drug or cyclooxygenase-2 inhibitor, intraoperatively only (odds ratio, 1.77 [99% CI, 1.11 to 2.82]), and preoperative day-of-surgery administration of an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker compared to no regular use (odds ratio, 1.84 [99% CI, 1.15 to 2.94]) were associated with increased odds for greater maximum stage AKI. These results were unchanged in model 2, with the additional finding of an inverse association between nadir hemoglobin concentration on postoperative day 1 and greater maximum stage AKI.

CONCLUSIONS

Avoiding intraoperative nonsteroidal anti-inflammatory drugs or cyclooxygenase-2 inhibitors is a potential strategy to mitigate the risk for postoperative AKI. The findings strengthen the rationale for a clinical trial comprehensively testing the risk-benefit ratio of these drugs in the perioperative period.

EDITOR’S PERSPECTIVE

Tranexamic acid in trauma: After 3 hours from injury, when is it safe and effective to use again?

Tranexamic acid (TXA) has proven mortality benefit if used early after traumatic injury, likely related to a combination of bleeding reduction and other non-bleeding effects. If TXA is given more than 3 h after traumatic injury, there is a significant and paradoxical increased risk of death due to bleeding. TXA has level 1 evidence for use as a bleeding reduction agent in isolated orthopedic operations, but in polytrauma patients undergoing orthopedic operations, it is not clear if and when TXA is safe or effective once outside the 3-h window of proven trauma efficacy.

Associations between the intraoperative fraction of inspired intraoperative oxygen administration and days alive and out of hospital after surgery

Background

There is limited knowledge about the effect of liberal intraoperative oxygen on non-infectious complications and overall recovery from surgery.

Methods

In this retrospective cohort study, we investigated associations between mean intraoperative fraction of inspired oxygen (FiO2), and outcome in adults undergoing elective surgery lasting more than 2 h at a large metropolitan New Zealand hospital from 2012 to 2020. Patients were divided into low, medium, and high oxygen groups (FiO2 ≤ 0.4, 0.41-0.59, ≥0.6). The primary outcome was days alive and out of hospital at 90 days (DAOH90). The secondary outcomes were post-operative complications and admission to the ICU.

Results

We identified 15,449 patients who met the inclusion criteria. There was no association between FiO2 and DAOH90 when high FiO2 was analysed according to three groups. Using high FiO2 as the reference group there was an adjusted mean (95% confidence interval [CI]) difference of 0.09 (-0.06 to 0.25) days (P = 0.25) and 0.28 (-0.05 to 0.62) days (P = 0.2) in the intermediate and low oxygen groups, respectively. Low FiO2 was associated with increased surgical site infection: the adjusted odds ratio (OR) for low compared with high FiO2 was 1.53 (95% CI 1.12-2.10). Increasing FiO2 was associated with respiratory complications: the adjusted OR associated with each 10% point increase in FiO2 was 1.17 (95% CI 1.08-1.26) and the incidence of being admitted to an ICU had an adjusted OR of 1.1 (95% CI 1.03-1.18).

Conclusions

We found potential benefits, and risks, associated with liberal intraoperative oxygen administration indicating that randomised controlled trials are warranted.

Intraoperative dexamethasone and chronic postsurgical pain: a propensity score-matched analysis of a large trial

BACKGROUND

Dexamethasone has been shown to reduce acute pain after surgery, but there is uncertainty as to its effects on chronic postsurgical pain (CPSP). We hypothesised that in patients undergoing major noncardiac surgery, a single intraoperative dose of dexamethasone increases the incidence of CPSP.

METHODS

We devised a propensity score-matched analysis of the ENIGMA-II trial CPSP dataset, aiming to compare the incidence of CPSP in patients who had received dexamethasone or not 12 months after major noncardiac surgery. The primary outcome was the incidence of CPSP. We used propensity score matching and inverse probability weighting to balance baseline variables to estimate the average marginal effect of dexamethasone on patient outcomes, accounting for confounding to estimate the average treatment effect on those treated with dexamethasone.

RESULTS

We analysed 2999 patients, of whom 116 of 973 (11.9%) receiving dexamethasone reported CPSP, and 380 of 2026 (18.8%) not receiving dexamethasone reported CPSP, unadjusted odds ratio 0.76 (95% confidence interval 0.78-1.00), P=0.052. After propensity score matching, CPSP occurred in 116 of 973 patients (12.2%) receiving dexamethasone and 380 of 2026 patients (13.8%) not receiving dexamethasone, adjusted risk ratio 0.88 (95% confidence interval 0.61-1.27), P=0.493. There was no difference between groups in quality of life or pain interference with daily activities, but 'least pain' (P=0.033) and 'pain right now' (P=0.034) were higher in the dexamethasone group.

CONCLUSIONS

Dexamethasone does not increase the risk of chronic postsurgical pain after major noncardiac surgery.

CLINICAL TRIAL REGISTRATION

Open Science Framework Registration DOI https://doi.org/10.17605/OSF.IO/ZDVB5.

Days at home alive after major surgery in patients with and without diabetes: an observational cohort study

OBJECTIVE

We hypothesized that days at home alive up to 30 days after surgery (DAH30), a novel patient-centered outcome metric, as well as long-term mortality, would be impaired in patients with type 1 or 2 diabetes mellitus (DM) undergoing major surgery.

METHODS

This cohort study investigated patients > 18 years with and without DM presenting for major non-cardiovascular, non-ambulatory surgical procedures at 23 hospitals in Sweden between 2007 and 2014. We identified 290,306 patients. Data were matched with various quality registers. The primary outcome was the composite score, DAH30. The secondary outcome was mortality from 31 to 365 days. Using multivariable logistic regression, significant independent risk factors influencing the primary and secondary outcomes were identified, and their adjusted odds ratios were calculated.

RESULTS

Patients with DM type 1 and 2 had significantly lower DAH30 as compared to non-diabetics. Patients with DM were older, had higher co-morbid burden, and needed more emergency surgery. After adjustment for illness severity and age, the odds of having a DAH30 less than 15, indicating death and/or complications, were significantly increased for both type 1 and type 2 diabetes. In the year after surgery, DM patients had a higher mortality as compared to those without diabetes.

CONCLUSIONS

The results of this large cohort study are likely broadly generalizable. To optimize patient and societal outcomes, specific perioperative care pathways for patients with diabetes should be evaluated.

Poor Agreement Between Preoperative Transthoracic Echocardiography and Intraoperative Transesophageal Echocardiography for Grading Diastolic Dysfunction

BACKGROUND

Guidelines for the evaluation and grading of diastolic dysfunction are available for transthoracic echocardiography (TTE). Transesophageal echocardiography (TEE) is used for this purpose intraoperatively but the level of agreement between these 2 imaging modalities for grading diastolic dysfunction is unknown. We assessed agreement between awake preoperative TTE and intraoperative TEE for grading diastolic dysfunction.

METHODS

In 98 patients undergoing cardiac surgery, key Doppler measurements were obtained using TTE and TEE at the following time points: TTE before anesthesia induction (TTEawake), TTE following anesthesia induction (TTEanesth), and TEE following anesthesia induction (TEEanesth). The primary endpoint was grade of diastolic dysfunction categorized by a simplified algorithm, and measured by TTEawake and TEEanesth, for which the weighted κ statistic assessed observed agreement beyond chance. Secondary endpoints were peak early diastolic lateral mitral annular tissue velocity (e'lat) and the ratio of peak early diastolic mitral inflow velocity (E) to e'lat (E/e'lat), measured by TTEawake and TEEanesth, were compared using Bland-Altman limits of agreement.

RESULTS

Disagreement in grading diastolic dysfunction by ≥1 grade occurred in 43 (54%) of 79 patients and by ≥2 grades in 8 (10%) patients with paired measurements for analysis, yielding a weighted κ of 0.35 (95% confidence interval [CI], 0.19-0.51) for the observed level of agreement beyond chance. Bland-Altman analysis of paired data for e'lat and E/e'lat demonstrated a mean difference (95% CI) of 0.51 (-0.06 to 1.09) and 0.70 (0.07-1.34), respectively, for measurements made by TTEawake compared to TEEanesth. The percentage (95% CI) of paired measurements for e'lat and E/e'lat that lay outside the [-2, +2] study-specified boundary of acceptable agreement was 36% (27%-48%) and 39% (29%-51%), respectively. Results were generally robust to sensitivity analyses, including comparing measurements between TTEawake and TTEanesth, between TTEanesth and TEEanesth, and after regrading diastolic dysfunction by the American Society of Echocardiography (ASE)/European Association of CardioVascular Imaging (EACVI) algorithm.

CONCLUSIONS

There was poor agreement between TTEawake and TEEanesth for grading diastolic dysfunction by a simplified algorithm, with disagreement by ≥1 grade in 54% and by ≥2 grades in 10% of the evaluable cohort. Future studies, including comparing the prognostic utility of TTEawake and TEEanesth for clinically important adverse outcomes that may be a consequence of diastolic dysfunction, are needed to understand whether this disagreement reflects random variability in Doppler variables, misclassification by the changed technique and physiological conditions of intraoperative TEE, or the accurate detection of a clinically relevant change in diastolic dysfunction.

A mixed methods study protocol to identify research priorities for perioperative medicine in Australia

Background

Clinical research in perioperative medicine requires the perspectives of patients and caregivers to increase its relevance and quality, benefiting both researchers and the community. Identifying these priorities will enable researchers, funders, and governing bodies to efficiently use scarce funding and resources. We aim to identify the top 10 research priorities in perioperative medical research in Australia.

Methods

A mixed-methods, exploratory-sequential design will be conducted. The study will include five phases. Initially, a published open-ended survey gathered responses from the population (researchers, healthcare workers, and consumers) regarding uncertainties/questions relevant to the population about perioperative medical research. We collected 544 questions and quantitatively analysed and grouped them according to the Standardised Endpoints in Perioperative Medicine-Core Outcomes Measures in Perioperative and Anaesthetic Care (StEP-COMPAC) endpoints. Using multicriteria decision-making software, workshops combining the population will be conducted to determine the top 10 priorities for perioperative medicine research for the Australian population.

Ethics and dissemination

Ethical approval to conduct the study was obtained from the Alfred Health (Australia) Human Research Ethics Committee (ID: 171/19). The findings will be disseminated in peer review publications, conferences, and dissemination across perioperative research networks. The top 10 priorities will be available to inform research funders, grant submissions, guidelines, and the population.

A vanguard randomised feasibility trial comparing three regimens of peri-operative oxygen therapy on recovery after major surgery

International recommendations encourage liberal administration of oxygen to patients having surgery under general anaesthesia, ostensibly to reduce surgical site infection. However, the optimal oxygen regimen to minimise postoperative complications and enhance recovery from surgery remains uncertain. The hospital operating theatre randomised oxygen (HOT-ROX) trial is a multicentre, patient- and assessor-blinded, parallel-group, randomised clinical trial designed to assess the effect of a restricted, standard care, or liberal peri-operative oxygen therapy regimen on days alive and at home after surgery in adults undergoing prolonged non-cardiac surgery under general anaesthesia. Here, we report the findings of the internal vanguard feasibility phase of the trial undertaken in four large metropolitan hospitals in Australia and New Zealand that included the first 210 patients of a planned overall 2640 trial sample, with eight pre-specified endpoints evaluating protocol implementation and safety. We screened a total of 956 participants between 1 September 2019 and 26 January 2021, with data from 210 participants included in the analysis. Median (IQR [range]) time-weighted average intra-operative Fi O2 was 0.30 (0.26-0.35 [0.20-0.59]) and 0.47 (0.44-0.51 [0.37-0.68]) for restricted and standard care, respectively (mean difference (95%CI) 0.17 (0.14-0.20), p < 0.001). Median time-weighted average intra-operative Fi O2 was 0.83 (0.80-0.85 [0.70-0.91]) for liberal oxygen therapy (mean difference (95%CI) compared with standard care 0.36 (0.33-0.39), p < 0.001). All feasibility endpoints were met. There were no significant patient adverse events. These data support the feasibility of proceeding with the HOT-ROX trial without major protocol modifications.

Predicting Death or Disability after Surgery in the Older Adult

BACKGROUND

Older patients are vulnerable to developing new or worsening disability after surgery. Despite this, patient or surgical characteristics predisposing to postoperative disability are poorly defined. The aim of the study was to develop and validate a model, subsequently transformed to point-score form, to predict 6-month death or disability in older patients after surgery.

METHODS

The authors built a prospective, single-center registry to develop and validate the prediction model. The registry included patients 70 yr of age or older undergoing elective and nonelective, cardiac and noncardiac surgery between May 25, 2017, and February 11, 2021, and combined clinical data from the electronic medical record, hospital administrative data (International Classification of Diseases, Tenth Revision, Australian Modification codes) and World Health Organization (Geneva, Switzerland) Disability Assessment Schedule data collected directly from the patients. Death or disability was defined as being dead or having a World Health Organization Disability Assessment Schedule score 16% or greater. Included patients were randomly divided into model development (70%) and internal validation (30%) cohorts. Once constructed, the logistic regression and point-score models were assessed using the internal validation cohort and an external validation cohort comprising data from a separate randomized trial.

RESULTS

Of 2,176 patients who completed the World Health Organization Disability Assessment Schedule immediately before surgery, 927 (43%) patients were disabled, and 413 (19%) had significant disability. By 6 months after surgery, 1,640 patients (75%) had data available for the primary outcome analysis. Of these patients, 195 (12%) patients had died, and 691 (42%) were dead or disabled. The developed point-score model included the preoperative World Health Organization Disability Assessment Schedule score, patient age, dementia, and chronic kidney disease. The point score model retained good discrimination in the internal (area under the curve, 0.74; 95% CI, 0.69 to 0.79) and external (area under the curve, 0.77; 95% CI, 0.74 to 0.80) validation data sets.

CONCLUSIONS

The authors developed and validated a point score model to predict death or disability in older patients after surgery.

EDITOR’S PERSPECTIVE

Tranexamic acid for haemostasis and beyond: does dose matter?

Tranexamic acid (TXA) is a widely used antifibrinolytic agent that has been used since the 1960's to reduce blood loss in various conditions. TXA is a lysine analogue that competes for the lysine binding sites in plasminogen and tissue-type plasminogen activator impairing its interaction with the exposed lysine residues on the fibrin surface. The presence of TXA therefore, impairs the plasminogen and tPA engagement and subsequent plasmin generation on the fibrin surface, protecting fibrin clot from proteolytic degradation. However, critical lysine binding sites for plasmin(ogen) also exist on other proteins and on various cell-surface receptors allowing plasmin to exert potent effects on other targets that are unrelated to classical fibrinolysis, notably in relation to immunity and inflammation. Indeed, TXA was reported to significantly reduce post-surgical infection rates in patients after cardiac surgery unrelated to its haemostatic effects. This has provided an impetus to consider TXA in other indications beyond inhibition of fibrinolysis. While there is extensive literature on the optimal dosage of TXA to reduce bleeding rates and transfusion needs, it remains to be determined if these dosages also apply to blocking the non-canonical effects of plasmin.

Postoperative analgesia for upper gastrointestinal surgery: a retrospective cohort analysis

BACKGROUND

Thoracic epidural analgesia is commonly used for upper gastrointestinal surgery. Intrathecal morphine is an appealing opioid-sparing non-epidural analgesic option, especially for laparoscopic gastrointestinal surgery.

METHODS

Following ethics committee approval, we extracted data from the electronic medical records of patients at Royal North Shore Hospital (Sydney, Australia) that had upper gastrointestinal surgery between November 2015 and October 2020. Postoperative morphine consumption and pain scores were modelled with a Bayesian mixed effect model.

RESULTS

A total of 427 patients were identified who underwent open (n = 300), laparoscopic (n = 120) or laparoscopic converted to open (n = 7) upper gastrointestinal surgery. The majority of patients undergoing open surgery received a neuraxial technique (thoracic epidural [58%, n = 174]; intrathecal morphine [21%, n = 63]) compared to a minority in laparoscopic approaches (thoracic epidural [3%, n = 4]; intrathecal morphine [12%, n = 14]). Intrathecal morphine was superior over non-neuraxial analgesia in terms of lower median oral morphine equivalent consumption and higher probability of adequate pain control; however, this effect was not sustained beyond postoperative day 2. Thoracic epidural analgesia was superior to both intrathecal and non-neuraxial analgesia options for both primary outcomes, but at the expense of higher rates of postoperative hypotension (60%, n = 113) and substantial technique failure rates (32%).

CONCLUSIONS

We found that thoracic epidural analgesia was superior to intrathecal morphine, and intrathecal morphine was superior to non-neuraxial analgesia, in terms of reduced postoperative morphine requirements and the probability of adequate pain control in patients who underwent upper gastrointestinal surgery. However, the benefits of thoracic epidural analgesia and intrathecal morphine were not sustained across all time periods regarding control of pain. The study is limited by its retrospective design, heterogenous group of upper gastrointestinal surgeries and confounding by indication.

Prehospital Tranexamic Acid for Severe Trauma

BACKGROUND

Whether prehospital administration of tranexamic acid increases the likelihood of survival with a favorable functional outcome among patients with major trauma and suspected trauma-induced coagulopathy who are being treated in advanced trauma systems is uncertain.

METHODS

We randomly assigned adults with major trauma who were at risk for trauma-induced coagulopathy to receive tranexamic acid (administered intravenously as a bolus dose of 1 g before hospital admission, followed by a 1-g infusion over a period of 8 hours after arrival at the hospital) or matched placebo. The primary outcome was survival with a favorable functional outcome at 6 months after injury, as assessed with the use of the Glasgow Outcome Scale-Extended (GOS-E). Levels on the GOS-E range from 1 (death) to 8 ("upper good recovery" [no injury-related problems]). We defined survival with a favorable functional outcome as a GOS-E level of 5 ("lower moderate disability") or higher. Secondary outcomes included death from any cause within 28 days and within 6 months after injury.

RESULTS

A total of 1310 patients were recruited by 15 emergency medical services in Australia, New Zealand, and Germany. Of these patients, 661 were assigned to receive tranexamic acid, and 646 were assigned to receive placebo; the trial-group assignment was unknown for 3 patients. Survival with a favorable functional outcome at 6 months occurred in 307 of 572 patients (53.7%) in the tranexamic acid group and in 299 of 559 (53.5%) in the placebo group (risk ratio, 1.00; 95% confidence interval [CI], 0.90 to 1.12; P = 0.95). At 28 days after injury, 113 of 653 patients (17.3%) in the tranexamic acid group and 139 of 637 (21.8%) in the placebo group had died (risk ratio, 0.79; 95% CI, 0.63 to 0.99). By 6 months, 123 of 648 patients (19.0%) in the tranexamic acid group and 144 of 629 (22.9%) in the placebo group had died (risk ratio, 0.83; 95% CI, 0.67 to 1.03). The number of serious adverse events, including vascular occlusive events, did not differ meaningfully between the groups.

CONCLUSIONS

Among adults with major trauma and suspected trauma-induced coagulopathy who were being treated in advanced trauma systems, prehospital administration of tranexamic acid followed by an infusion over 8 hours did not result in a greater number of patients surviving with a favorable functional outcome at 6 months than placebo. (Funded by the Australian National Health and Medical Research Council and others; PATCH-Trauma ClinicalTrials.gov number, NCT02187120.).

Machine learning to predict myocardial injury and death after non-cardiac surgery

Myocardial injury due to ischaemia within 30 days of non-cardiac surgery is prognostically relevant. We aimed to determine the discrimination, calibration, accuracy, sensitivity and specificity of single-layer and multiple-layer neural networks for myocardial injury and death within 30 postoperative days. We analysed data from 24,589 participants in the Vascular Events in Non-cardiac Surgery Patients Cohort Evaluation study. Validation was performed on a randomly selected subset of the study population. Discrimination for myocardial injury by single-layer vs. multiple-layer models generated areas (95%CI) under the receiver operating characteristic curve of: 0.70 (0.69-0.72) vs. 0.71 (0.70-0.73) with variables available before surgical referral, p < 0.001; 0.73 (0.72-0.75) vs. 0.75 (0.74-0.76) with additional variables available on admission, but before surgery, p < 0.001; and 0.76 (0.75-0.77) vs. 0.77 (0.76-0.78) with the addition of subsequent variables, p < 0.001. Discrimination for death by single-layer vs. multiple-layer models generated areas (95%CI) under the receiver operating characteristic curve of: 0.71 (0.66-0.76) vs. 0.74 (0.71-0.77) with variables available before surgical referral, p = 0.04; 0.78 (0.73-0.82) vs. 0.83 (0.79-0.86) with additional variables available on admission but before surgery, p = 0.01; and 0.87 (0.83-0.89) vs. 0.87 (0.85-0.90) with the addition of subsequent variables, p = 0.52. The accuracy of the multiple-layer model for myocardial injury and death with all variables was 70% and 89%, respectively.

Systematic reviews and consensus definitions for the Standardised Endpoints in Perioperative Medicine (StEP) initiative: mortality, morbidity, and organ failure

BACKGROUND

Mortality, morbidity, and organ failure are important and common serious harms after surgery. However, there are many candidate measures to describe these outcome domains. Definitions of these measures are highly variable, and validity is often unclear. As part of the International Standardised Endpoints in Perioperative Medicine (StEP) initiative, this study aimed to derive a set of standardised and valid measures of mortality, morbidity, and organ failure for use in perioperative clinical trials.

METHODS

Three domains of endpoints (mortality, morbidity, and organ failure) were explored through systematic literature review and a three-stage Delphi consensus process using methods consistently applied across the StEP initiative. Reliability, feasibility, and patient-centredness were assessed in round 3 of the consensus process.

RESULTS

A high level of consensus was achieved for two mortality time points, 30-day and 1-yr mortality, and these two measures are recommended. No organ failure endpoints achieved threshold criteria for consensus recommendation. The Clavien-Dindo classification of complications achieved threshold criteria for consensus in round 2 of the Delphi process but did not achieve the threshold criteria in round 3 where it scored equivalently to the Post Operative Morbidity Survey. Clavien-Dindo therefore received conditional endorsement as the most widely used measure. No composite measures of organ failure achieved an acceptable level of consensus.

CONCLUSIONS

Both 30-day and 1-yr mortality measures are recommended. No measure is recommended for organ failure. One measure (Clavien-Dindo) is conditionally endorsed for postoperative morbidity, but our findings suggest that no single endpoint offers a reliable and valid measure to describe perioperative morbidity that is not dependent on the quality of deli-vered care. Further refinement of current measures, or development of novel measures, of postoperative morbidity might improve consensus in this area.

Perioperative outcomes in intermediate and high-risk patients after major surgery following introduction of a dedicated perioperative medicine team: A single centre cohort study

Intermediate and high-risk patients undergoing surgery are often managed on a surgical ward in the absence of haemodynamic or ventilatory support requirements necessitating intensive care unit or high dependency unit admission. We describe a model of care for the multidisciplinary management of selected postoperative patients and the epidemiology of patients managed using this model at a tertiary Australian hospital.Of 25,139 patients undergoing inpatient surgery at our institution over a two-year period, 506 (2%) were referred to the Perioperative Medicine team. The median age of patients referred was 74 years; 85% had an American Society of Anesthesiologists physical status ≥3, and 44% underwent emergency surgery. Major complication or death within 30 days was 44.2% (213/482). The most common complications, as defined by the American College of Surgeons National Surgical Quality Improvement Program were transfusion within 72 h (17.4%), pneumonia/aspiration pneumonitis (11.3%), and acute renal failure (10.6%); median time to Medical Emergency Team call was 146 (interquartile range 77-279) h.Sixty-six percent of referred patients (280/423) required an intervention during their time under the service. This high incidence indicates that this population of patients merits closer attention, including routine measurement and reporting of postoperative outcomes to monitor and improve quality of care at our institution as part of an integrated perioperative service. We believe that with so much current focus on perioperative medicine, it is important we translate this to clinical care by evolving traditional models of management into more innovative strategies to meet the complex demands of today's surgical patients.

Postoperative systemic inflammatory dysregulation and corticosteroids: a narrative review

In some patients, the inflammatory-immune response to surgical injury progresses to a harmful, dysregulated state. We posit that postoperative systemic inflammatory dysregulation forms part of a pathophysiological response to surgical injury that places patients at increased risk of complications and subsequently prolongs hospital stay. In this narrative review, we have outlined the evolution, measurement and prediction of postoperative systemic inflammatory dysregulation, distinguishing it from a healthy and self-limiting host response. We reviewed the actions of glucocorticoids and the potential for heterogeneous responses to peri-operative corticosteroid supplementation. We have then appraised the evidence highlighting the safety of corticosteroid supplementation, and the potential benefits of high/repeated doses to reduce the risks of major complications and death. Finally, we addressed how clinical trials in the future should target patients at higher risk of peri-operative inflammatory complications, whereby corticosteroid regimes should be tailored to modify not only the a priori risk, but also further adjusted in response to markers of an evolving pathophysiological response.

Perioperative oxygen administration in patients undergoing major non-cardiac surgery under general anaesthesia in Australia and New Zealand

The practice of anaesthetists relating to the administration of intraoperative oxygen has not been previously quantified in Australia and New Zealand. The optimal regimen of intraoperative oxygen administration to patients undergoing surgery under general anaesthesia is not known, and international recommendations for oxygen therapy are contradictory; the World Health Organization (WHO) recommend administering an intraoperative fraction of inspired oxygen of at least 0.8, while the World Federation of Societies of Anaesthesiologists, British Thoracic Society, and Thoracic Society of Australia and New Zealand recommend a more restrictive approach. We conducted a prospective observational study to describe the pattern of intraoperative oxygen administration among anaesthetists in Australia and New Zealand and, second, to determine the proportion of anaesthetists who administer intraoperative inspired oxygen in accordance with the WHO recommendations. We identified 150 anaesthetists from ten metropolitan hospitals in Australia and New Zealand and observed the patterns of intraoperative oxygen administration to American Society of Anesthesiologists physical status classification (ASA) 3 or 4 patients undergoing prolonged surgery under general anaesthesia. The median (interquartile range) intraoperative time-weighted mean fraction of inspired oxygen (FiO₂) for all participants in the study was 0.47 (0.40-0.55). Three out of 150 anaesthetists (2%, 95% confidence interval 0.4 to 5.7) administered an average intraoperative FiO₂ of at least 0.8. These findings indicate that most anaesthetists routinely administer an intermediate level of oxygen for ASA 3 or 4 adult patients undergoing prolonged surgery in Australia and New Zealand, rather than down-titrating inspired oxygen to a target pulse oximetry reading (SpO₂) or administering liberal perioperative oxygen therapy in line with the current WHO recommendation.

LidocAine Versus Opioids In MyocarDial infarction: the AVOID-2 randomized controlled trial

AIMS

Opioid analgesia has been shown to interfere with the bioavailability of oral P2Y12 inhibitors prompting the search for safe and effective non-opioid analgesics to treat ischaemic chest pain.

METHODS AND RESULTS

The lidocAine Versus Opioids In MyocarDial infarction trial was a prospective, Phase II, prehospital, open-label, non-inferiority, randomized controlled trial enrolling patients with suspected STEACS with moderate to severe pain [numerical rating scale (NRS) at least 5/10]. Intravenous lidocaine (maximum dose 300 mg) or intravenous fentanyl (up to 50 µg every 5 min) were administered as prehospital analgesia. The co-primary end points were prehospital pain reduction and adverse events requiring intervention. Secondary end points included peak cardiac troponin I, cardiac MRI (cMRI) assessed myocardial infarct size and clinical outcomes to 30 days. A total of 308 patients were enrolled. The median reduction in pain score (NRS) was 4 vs. 3 in the fentanyl and lidocaine arms, respectively, for the primary efficacy end point [estimated median difference -1 (95% confidence interval -1.58, -0.42, P = 0.5 for non-inferiority, P = 0.001 for inferiority of lidocaine)]. Adverse events requiring intervention occurred in 49% vs. 36% of the fentanyl and lidocaine arms which met non-inferiority and superiority favouring lidocaine (P = 0.016 for superiority). No significant differences in myocardial infarct size and clinical outcomes at 30 days were seen.

CONCLUSION

IV Lidocaine did not meet the criteria for non-inferiority with lower prehospital pain reduction than fentanyl but was safe and better tolerated as analgesia in ST-elevation myocardial infarction (STEMI). Future trials testing non-opioid analgesics in STEMI and whether opioid avoidance improves clinical outcomes are needed.

TRIAL REGISTRATION

CTRN12619001521112p.

Association of menstrual cycle and postoperative quality of recovery in premenopausal women: a prospective cohort study

Background

Women have poorer quality of postoperative recovery from general anaesthesia than men. This persists for at least 3 days postoperatively, and is more pronounced in premenopausal women. Studies of menstrual cycle effects on pain or postoperative nausea and vomiting report conflicting results. Our aim was to determine whether menstrual cycle phase is associated with quality of recovery after surgery in premenopausal women.

Methods

Eligible women aged 18-45 yr undergoing wisdom teeth extraction or laparoscopic cholecystectomy under general anaesthesia with volatile agents were recruited from Epworth HealthCare Richmond in Melbourne, Australia from 2019 to 2021. Menstrual history and progesterone levels were used to determine cycle phase (luteal or non-luteal). Linear mixed and generalised linear regression models were fitted to examine differences in Quality of Recovery-15 (QoR-15) score on postoperative days 1 (primary outcome) and 3, and secondary outcomes (pain, analgesic effectiveness, postoperative nausea and vomiting, prolonged hospital admission), between groups, adjusting for confounders.

Results

A total of 177 women were recruited (74 luteal, 103 non-luteal). Six (3%) underwent laparoscopic cholecystectomy. Estimated mean differences (95% confidence interval; P-value) in adjusted QoR-15 scores between luteal and non-luteal groups were -0.05 (-5.86 to 5.76; P=0.986) and 1.40 (-4.41 to 7.21; P=0.636) on postoperative days 1 and 3, respectively. Secondary outcomes were not different between groups.

Conclusions

There was no significant difference in postoperative QoR-15 score or other outcomes between women in the luteal and non-luteal phases of their cycle. Women can be reassured that cycle phase does not impact postoperative quality of recovery when undergoing minor surgery under general anaesthesia.

Clinical trial registration

ACTRN12618000240246.

Platform trials for anaesthesia and perioperative medicine: a narrative review

Large randomised trials provide the most reliable evidence of effectiveness of new treatments in clinical practice. However, the time and resources required to complete such trials can be daunting. An overarching clinical trial platform focused on a single condition or type of surgery, aiming to compare several treatments, with an option to stop any or add in new treatment options, can provide greater efficiency. This has the potential to accelerate knowledge acquisition and identify effective, ineffective, or harmful treatments faster. The master protocol of the platform defines the study population(s) and standardised procedures. Ineffective or harmful treatments can be discarded or study drug dose modified during the life cycle of the trial. Other adaptive elements that can be modified include eligibility criteria, required sample size for any comparison(s), randomisation assignment ratio, and the addition of other promising treatment options. There are excellent opportunities for anaesthetists to establish platform trials in perioperative medicine. Platform trials are highly efficient, with the potential to provide quicker answers to important clinical questions that lead to improved patient care.

Hyperbaric Oxygen for Lower Limb Trauma (HOLLT): an international multi-centre randomised clinical trial

Introduction: Hyperbaric oxygen treatment (HBOT) is sometimes used in the management of open fractures and severe soft tissue crush injury, aiming to reduce complications and improve outcomes. Methods: Patients with open tibial fractures were randomly assigned within 48 hours of injury to receive standard trauma care or standard care plus 12 sessions of HBOT. The primary outcome was the incidence of necrosis or infection or both occurring within 14 days of injury. Results: One-hundred and twenty patients were enrolled. Intention to treat primary outcome occurred in 25/58 HBOT assigned patients and 34/59 controls (43% vs 58%, odds ratio (OR) 0.55, 95% confidence interval (CI) 0.25 to 1.18, P = 0.12). Tissue necrosis occurred in 29% of HBOT patients and 53% of controls (OR 0.35, 95% CI 0.16 to 0.78, P = 0.01). There were fewer late complications in patients receiving HBOT (6/53 vs 18/52, OR 0.22, 95% CI 0.08 to 0.64, P = 0.007) including delayed fracture union (5/53 vs 13/52, OR 0.31, 95% CI 0.10 to 0.95, P = 0.04). Quality of life measures at one and two years were superior in HBOT patients. The mean score difference in short form 36 was 2.90, 95% CI 1.03 to 4.77, P = 0.002, in the short musculoskeletal function assessment (SMFA) was 2.54, 95% CI 0.62 to 4.46, P = 0.01; and in SMFA daily activities was 19.51, 95% CI 0.06 to 21.08, P = 0.05. Conclusions: In severe lower limb trauma, early HBOT reduces tissue necrosis and the likelihood of long-term complications, and improves functional outcomes. Future research should focus on optimal dosage and whether HBOT has benefits for other injury types.

Measurement properties of the WHO Disability Assessment Schedule 2.0 for evaluating functional status after inpatient surgery

BACKGROUND

Expert recommendations propose the WHO Disability Assessment Schedule (WHODAS) 2.0 as a core outcome measure in surgical studies, yet data on its long-term measurement properties remain limited. These were evaluated in a secondary analysis of the Measurement of Exercise Tolerance before Surgery (METS) prospective cohort.

METHODS

Participants were adults (40 years of age or older) who underwent inpatient non-cardiac surgery. The 12-item WHODAS and EQ-5DTM-3L questionnaires were administered preoperatively (in person) and 1 year postoperatively (by telephone). Responsiveness was characterized using standardized response means (SRMs) and correlation coefficients between change scores. Construct validity was evaluated using correlation coefficients between 1-year scores and comparisons of WHODAS scores across clinically relevant subgroups.

RESULTS

The analysis included 546 patients. There was moderate correlation between changes in WHODAS and various EQ-5DTM subscales. The strongest correlation was between changes in WHODAS and changes in the functional domains of the EQ-5D-3L-for example, mobility (Spearman's rho 0.40, 95 per cent confidence interval [c.i.] 0.32 to 0.48) and usual activities (rho 0.45, 95 per cent c.i. 0.30 to 0.52). When compared across quartiles of EQ-5D index change, median WHODAS scores followed expected patterns of change. In subgroups with expected functional status changes, the WHODAS SRMs ranged from 'small' to 'large' in the expected directions of change. At 1 year, the WHODAS demonstrated convergence with the EQ-5D-3L functional domains, and good discrimination between patients with expected differences in functional status.

CONCLUSION

The WHODAS questionnaire has construct validity and responsiveness as a measure of functional status at 1 year after major surgery.

Methylomic and transcriptomic characterization of postoperative systemic inflammatory dysregulation

In this study, we define and validate a state of postoperative systemic inflammatory dysregulation (PSID) based on postoperative phenotypic extremes of plasma C-reactive protein concentration following major abdominal surgery. PSID manifested clinically with significantly higher rates of sepsis, complications, longer hospital stays and poorer short, and long-term outcomes. We hypothesized that PSID will be associated with, and potentially predicted by, altered patterns of genome-wide peripheral blood mononuclear cell differential DNA methylation and gene expression. We identified altered DNA methylation and differential gene expression in specific immune and metabolic pathways during PSID. Our findings suggest that dysregulation results in, or from, dramatic changes in differential DNA methylation and highlights potential targets for early detection and treatment. The combination of altered DNA methylation and gene expression suggests that dysregulation is mediated at multiple levels within specific gene sets and hence, nonspecific anti-inflammatory treatments such as corticosteroids alone are unlikely to represent an effective therapeutic strategy.

Hospital costs and factors associated with days alive and at home after surgery (DAH30 )

OBJECTIVE

To assess the relationships of patient and surgical factors and hospital costs with the number of days alive and at home during the 30 days following surgery (DAH₃₀ ).

DESIGN

Retrospective cohort study; analysis of Medibank Private health insurance hospital claims data, Australia, 1 January 2016 - 31 December 2017.

SETTING, PARTICIPANTS

Admissions of adults (18 years or older) to hospitals for elective or emergency inpatient surgery with anaesthesia covered by private health insurance, Australia, 1 January 2016 - 31 December 2017.

MAIN OUTCOME MEASURES

Associations between DAH₃₀ and total hospital costs, and between DAH₃₀ and surgery risk factors.

RESULTS

Complete data were available for 126 788 of 181 281 eligible patients (69.9%); their median age was 62 years (IQR, 47-73 years), 72 872 were women (57%), and 115 117 had undergone elective surgery (91%). The median DAH₃₀ was 27.1 days (IQR, 24.2-28.8 days), the median hospital cost per patient was $10 358 (IQR, $6624-20 174). The association between DAH₃₀ and total hospital costs was moderate (Spearman ρ = -0.60; P < 0.001). Median DAH₃₀ declined with age, comorbidity score, ASA physical status score, and surgical severity and duration, and was also lower for women.

CONCLUSIONS

DAH₃₀ is a validated, patient-centred outcome measure of post-surgical outcomes; higher values reflect shorter hospital stays and fewer serious complications, re-admissions, and deaths. DAH₃₀ can be used to benchmark quality of surgical care and to monitor quality improvement programs for reducing the costs of surgical and other peri-operative care.

Development of the 'AusPROM' recommendations for elective surgery patients

ObjectiveImplementing the routine collection of patient reported outcome measures (PROMs) is key to improving healthcare quality and patient satisfaction. The implementation process can be strengthened through staff and patient co-design. The aim of this project was to develop a set of Australian PROM implementation recommendations ('AusPROM') to guide rapid translation into practice.MethodsStaff working across 29 Australian private hospitals participated in the project. The hospitals provided elective surgery and spanned each state and territory of Australia. Staff engaged in a Delphi technique to develop the AusPROM, which involved three iterative focus groups. To ensure full disclosure, staff were also provided with additional project-related data sources throughout the Delphi technique. This included data from a patient focus group (patient co-design), patient survey, technical feasibility testing, 3 months of pilot testing (four sites), 3 months of national implementation (29 sites) and global evidence. This process ensured that staff and patient feedback was used to co-design the three iterations of the AusPROM recommendations until the final agreed version was established.ResultsA total of 22 AusPROM recommendations were included in the final iteration. The recommendations covered the domains of PROM characteristics, healthcare organisation characteristics, external influences, staff and patient characteristics, and facilitators to implementing AusPROMS in routine practice.ConclusionThe AusPROM recommendations offer practical considerations for the implementation of PROMs in hospitals. The iterative nature of the Delphi technique ensured that staff and patient co-design were central to the development of the AusPROM recommendations.

Current approaches to acute postoperative pain management after major abdominal surgery: a narrative review and future directions

Poorly controlled postoperative pain is associated with increased morbidity, negatively affects quality of life and functional recovery, and is a risk factor for persistent pain and longer-term opioid use. Up to 10% of opioid-naïve patients have persistent opioid use after many types of surgeries. Opioid-related side-effects and the opioid abuse epidemic emphasise the need for alternative, opioid-minimising, multimodal analgesic strategies, including neuraxial (epidural/intrathecal) techniques, truncal nerve blocks, and lidocaine infusions. The preference for minimally invasive surgical techniques has changed anaesthetic and analgesic requirements in abdominal surgery compared with open laparotomy, leading to a decline in popularity of epidural anaesthesia and an increasing interest in intrathecal morphine and truncal nerve blocks. Limited research exists on patient quality of recovery using specific analgesic techniques after intra-abdominal surgery. Poorly controlled postoperative pain after major abdominal surgery should be a research priority as it affects patient-centred short-term and long-term outcomes (including quality of life scores, return to function measurements, disability-free survival) and has broad community health and economic implications.

A systematic review of economic evaluations of preoperative smoking cessation for preventing surgical complications

BACKGROUND

Whilst there is a substantial body of evidence on the costs and benefits of smoking cessation generally, the benefits of routinely providing smoking cessation for surgical populations are less well known. This review summarises the evidence on the cost-effectiveness of preoperative smoking cessation to prevent surgical complications.

MATERIALS AND METHODS

A search of the Cochrane, Econlit, EMBASE, Health Technology Assessment, Medline Complete and Scopus databases was conducted from inception until 23/06/2021. Peer-reviewed, English-language articles describing economic evaluations of preoperative smoking cessation interventions to prevent surgical complications were included. Search results were independently screened for potentially eligible studies. Study characteristics, economic evaluation methods and cost-effectiveness results were extracted by one reviewer and details checked by a second. Two authors independently assessed reporting and methodological quality using the Consolidated Health Economic Evaluation Reporting Standards statement (CHEERS) and the Quality of Health Economic Studies Instrument checklist (QHES) respectively.

RESULTS

After removing duplicates, twenty full text articles were screened from 1423 database records, resulting in six included economic evaluations. Studies from the United States (n = 4), France (n = 1) and Spain (n = 1) were reported between 2009 and 2020. Four evaluations were conducted from a payer perspective. Two-thirds of evaluations were well-conducted (mean score 83) and well-reported (on average, 86% items reported). All studies concluded preoperative smoking cessation is cost-effective for preventing surgical complications; results ranged from cost saving to €53,131 per quality adjusted life year gained.

CONCLUSIONS

Preoperative smoking cessation is cost-effective for preventing surgical complications from a payer or provider perspective when compared to standard care. There is no evidence from outside the United States and Europe to inform healthcare providers, funders and policy-makers in other jurisdictions and more information is needed to clarify the optimal point of implementation to maximise cost-effectiveness of preoperative smoking cessation intervention.

SYSTEMATIC REVIEW REGISTRATION NUMBER

PROSPERO 2021 CRD42021257740. RESEARCH REGISTRY REGISTRATION NUMBER: reviewregistry1369.

Comparison of 6-month outcomes of sepsis versus non-sepsis critically ill patients receiving mechanical ventilation

Background

Data on long-term outcomes after sepsis-associated critical illness have mostly come from small cohort studies, with no information about the incidence of new disability. We investigated whether sepsis-associated critical illness was independently associated with new disability at 6 months after ICU admission compared with other types of critical illness.

Methods

We conducted a secondary analysis of a multicenter, prospective cohort study in six metropolitan intensive care units in Australia. Adult patients were eligible if they had been admitted to the ICU and received more than 24 h of mechanical ventilation. There was no intervention.

Results

The primary outcome was new disability measured with the WHO Disability Assessment Schedule 2.0 (WHODAS) 12 level score compared between baseline and 6 months. Between enrollment and follow-up at 6 months, 222/888 (25%) patients died, 100 (35.5%) with sepsis and 122 (20.1%) without sepsis (P < 0.001). Among survivors, there was no difference for the incidence of new disability at 6 months with or without sepsis, 42/106 (39.6%) and 106/300 (35.3%) (RD, 0.00 (− 10.29 to 10.40), P = 0.995), respectively. In addition, there was no difference in the severity of disability, health-related quality of life, anxiety and depression, post-traumatic stress, return to work, financial distress or cognitive function.

Conclusions

Compared to mechanically ventilated patients of similar acuity and length of stay without sepsis, patients with sepsis admitted to ICU have an increased risk of death, but survivors have a similar risk of new disability at 6 months.

Trial registration NCT03226912, registered July 24, 2017.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-022-04041-w.

Comparison of 6-Month Outcomes of Survivors of COVID-19 versus Non-COVID-19 Critical Illness

Rationale: The outcomes of survivors of critical illness due to coronavirus disease (COVID-19) compared with non-COVID-19 are yet to be established. Objectives: We aimed to investigate new disability at 6 months in mechanically ventilated patients admitted to Australian ICUs with COVID-19 compared with non-COVID-19. Methods: We included critically ill patients with COVID-19 and non-COVID-19 from two prospective observational studies. Patients were eligible if they were adult (age ⩾ 8 yr) and received ⩾24 hours of mechanical ventilation. In addition, patients with COVID-19 were eligible with a positive laboratory PCR test for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Measurements and Main Results: Demographic, intervention, and hospital outcome data were obtained from electronic medical records. Survivors were contacted by telephone for functional outcomes with trained outcome assessors using the World Health Organization Disability Assessment Schedule 2.0. Between March 6, 2020, and April 21, 2021, 120 critically ill patients with COVID-19, and between August 2017 and January 2019, 199 critically ill patients without COVID-19, fulfilled the inclusion criteria. Patients with COVID-19 were older (median [interquartile range], 62 [55-71] vs. 58 [44-69] yr; P = 0.019) with a lower Acute Physiology and Chronic Health Evaluation II score (17 [13-20] vs. 19 [15-23]; P = 0.011). Although duration of ventilation was longer in patients with COVID-19 than in those without COVID-19 (12 [5-19] vs. 4.8 [2.3-8.8] d; P < 0.001), 180-day mortality was similar between the groups (39/120 [32.5%] vs. 70/199 [35.2%]; P = 0.715). The incidence of death or new disability at 180 days was similar (58/93 [62.4%] vs. 99/150 [66/0%]; P = 0.583). Conclusions: At 6 months, there was no difference in new disability for patients requiring mechanical ventilation for acute respiratory failure due to COVID-19 compared with non-COVID-19. Clinical trial registered with www.clinicaltrials.gov (NCT04401254).

Tranexamic acid alters the immunophenotype of phagocytes after lower limb surgery

Background

Tranexamic acid (TXA) is an antifibrinolytic agent frequently used in elective surgery to reduce blood loss. We recently found it also acts as a potent immune-modulator in patients undergoing cardiac surgery.

Methods

Patients undergoing lower limb surgery were enrolled into the “Tranexamic Acid in Lower Limb Arthroplasty” (TALLAS) pilot study. The cellular immune response was characterised longitudinally pre- and post-operatively using full blood examination (FBE) and comprehensive immune cell phenotyping by flowcytometry. Red blood cells and platelets were determined in the FBE and levels of T cell cytokines and the plasmin-antiplasmin complex determined using ELISA.

Results

TXA administration increased the proportion of circulating CD141+ conventional dendritic cells (cDC) on post-operative day (POD) 3. It also reduced the expression of CD83 and TNFR2 on classical monocytes and levels of circulating IL-10 at the end of surgery (EOS) time point, whilst increasing the expression of CCR4 on natural killer (NK) cells at EOS, and reducing TNFR2 on POD-3 on NK cells. Red blood cells and platelets were decreased to a lower extent at POD-1 in the TXA group, representing reduced blood loss.

Conclusion

In this investigation we have extended our examination on the immunomodulatory effects of TXA in surgery by also characterising the end of surgery time point and including B cells and neutrophils in our immune analysis, elucidating new immunophenotypic changes in phagocytes as well as NK cells. This study enhances our understanding of TXA-mediated effects on the haemostatic and immune response in surgery, validating changes in important functional immune cell subsets in orthopaedic patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12959-022-00373-3.

Towards a national perioperative outcomes registry: A survey of perioperative electronic medical record utilisation to support quality assurance and research at Australian and New Zealand College of Anaesthetists Clinical Trials Network hospitals in Australia

In Australia, 2.7 million surgical procedures are performed annually. Historically, a lack of perioperative data standardisation and infrastructure has limited pooling of routinely collected data across institutions. We surveyed Australian and New Zealand College of Anaesthetists (ANZCA) Clinical Trials Network hospitals to investigate current and potential uses of perioperative electronic medical record data for research and quality assurance.A targeted survey was sent to 131 ANZCA Clinical Trials Network-affiliated hospitals in Australia. The primary aim was to map current electronic data collection methods and data utilisation in six domains of the perioperative pathway.The survey response rate was 32%. Electronic data recording in the six domains ranged from 19% to 85%. Where electronic data exist, the ability of anaesthesiology departments to export them for analysis ranged from 27% to 100%. The proportion of departments with access to data exports that are regularly exporting the data for quality assurance or research ranged from 13% to 58%.The existence of a perioperative electronic medical record does not automatically lead to the data being used to measure and improve clinical outcomes. The first barrier is clinician access to data exports. Even when this barrier is overcome, a large gap remains between the proportion of departments able to access data exports and those using the data regularly to inform and improve clinical practice. We believe this gap can be addressed by establishing a national perioperative outcomes registry to lead high-quality multicentre registry research and quality assurance in Australia.

Analgesia for major laparoscopic abdominal surgery: a randomised feasibility trial using intrathecal morphine

Effective pain control enhances patient recovery after surgery. Laparoscopic techniques for major abdominal surgery are increasingly utilised to reduce surgical trauma. Intrathecal morphine is an attractive analgesic option that is gaining popularity. However, limited evidence guides its use in the setting of laparoscopic surgery. In addition, enhanced recovery after surgery pathways advocate opioid-sparing techniques. We conducted a feasibility trial to compare intrathecal morphine with non-neuraxial analgesia in laparoscopic or laparoscopic-assisted major abdominal surgery to inform the design of a future large clinical trial. This multicentre, double-blind, randomised controlled trial was conducted at two tertiary hospitals in Australia. Fifty-one patients were randomly allocated to receive either intrathecal morphine (intervention group) or a sham subcutaneous injection of normal saline in the lumbar area (control group) immediately before the induction of general anaesthesia. Co-primary outcomes were patient recruitment and successful adherence to treatment allocation as per the study protocol. The primary endpoints of feasibility and protocol adherence were met with a 46% recruitment rate (51 of 110 eligible patients) and 96% protocol adherence. There was only one patient with failed access to the intrathecal space. For secondary endpoints, fewer patients in the intrathecal morphine group required opioids in the post-anaesthesia care unit, their postoperative pain scores at rest were lower across the four time-points measured (p = 0.007), but not dynamic pain scores (p = 0.061), and pruritus was more common following intrathecal morphine (p = 0.007). Total oral morphine equivalents until postoperative day 3 were less in the intrathecal morphine group (median (95%CI) difference 82 (-13 to 168) mg), but this reduction was not statistically significant (p = 0.10). These findings support conducting a definitive clinical trial.

Low-Concentration Norepinephrine Infusion for Major Surgery: A Safety and Feasibility Pilot Randomized Controlled Trial

BACKGROUND

Prevention of hypotension during the intra- and postoperative period is an important goal. Peripheral administration of low-concentration norepinephrine may be a safe and effective strategy to reduce the risk of hypotension.

METHODS

We conducted a 2-center, randomized pilot feasibility trial, with a target of 60 adult patients undergoing major noncardiac surgery. We randomized patients to receive a peripheral low-concentration (10 µg/mL) norepinephrine or placebo (saline 0.9%) infusion. The study drug infusion was titrated to achieve a minimum systolic blood pressure target, preselected within 10% of baseline value and within the range limit 100 to 120 mm Hg during surgery and for up to 4 or 24 hours postoperatively.

RESULTS

We achieved a high consent rate (84%), successful study drug administration throughout surgery (98% of patients) and absence of unblinding. There were no important study drug-related adverse events. The average intraoperative systolic blood pressure was 120 ± 12.6 mm Hg in the norepinephrine group and 115 ± 14.9 mm Hg in the placebo group. The mean difference between the intraoperative systolic blood pressure achieved less the preselected minimum systolic blood pressure target was 10.0 ± 12.7 mm Hg in the norepinephrine group and 2.9 ± 14.7 mm Hg in the placebo group; difference in means, 7.1 (95% confidence interval, 0.2-14.0) mm Hg.

CONCLUSIONS

A future large trial evaluating the effectiveness and safety of peripheral administration of low-concentration norepinephrine during the perioperative period is feasible, and likely to achieve a minimum systolic blood pressure threshold.

Association between pre-hospital chest pain severity and myocardial injury in ST elevation myocardial infarction: A post-hoc analysis of the AVOID study

Background

We sought to determine if an association exists between prehospital chest pain severity and markers of myocardial injury.

Methods and Results

Patients with confirmed ST elevation myocardial infarction (STEMI) treated by emergency medical services were included in this retrospective cohort analysis of the AVOID study. The primary endpoint was the association of pre-hospital initial chest pain severity, cardiac biomarkers and infarct size based on cardiac magnetic resonance imaging. Groups were categorized based on moderate to severe chest pain (numerical rating scale pain ≥ 5/10) or less than moderate severity to compare procedural and clinical outcomes. 414 patients were included in the analysis. There was a weak correlation between initial pre-hospital chest pain severity and peak creatine kinase (r = 0.16, p = 0.001) and peak cardiac troponin I (r = 0.14, p = 0.005). Both were no longer significant after adjusting for known confounders. There was no association between moderate to severe chest pain on arrival and major adverse cardiac events at 6 months (20% vs. 14%, p=0.12). There was a weak correlation between history of ischemic heart disease (r = 0.16, p = 0.001), percutaneous coronary intervention (r = 0.16, p = 0.001), left anterior descending artery (r = 0.12, p = 0.012) as the culprit vessel and a weak negative correlation between age (r = -0.14, p = 0.039) and chest pain.

Conclusion

Only a weak association between pre-hospital chest pain severity and markers of myocardial injury was identified, supporting more judicious use of opioid analgesia with a focus on patient comfort.

Minimal clinically important difference in days at home up to 30 days after surgery

Patient-centred outcomes are increasingly recognised as crucial measures of healthcare quality. Days alive and at home up to 30 days after surgery (DAH₃₀ ) is a validated and readily obtainable patient-centred outcome measure that integrates much of the peri-operative patient journey. However, the minimal difference in DAH₃₀ that is clinically important to patients is unknown. We designed and administered a 28-item survey to evaluate the minimal clinically important difference in DAH₃₀ among adult patients undergoing inpatient surgery. Patients were approached pre-operatively or within 2 days postoperatively. We did not study patients undergoing day surgery or nursing home residents. Patients ranked their opinions on the importance of discharge home using a Likert scale (from 1, not important at all to 6, extremely important) and the minimum number of extra days at home that would be meaningful using this scale. We recruited 104 patients; the survey was administered pre-operatively to 45 patients and postoperatively to 59 patients. The mean (SD) age was 53.5 (16.5) years, and 51 (49%) patients were male. Patients underwent a broad range of surgery of mainly intermediate (55%) to major (33%) severity. The median minimal clinically important difference for DAH₃₀ was 3 days; this was consistent across a broad range of scenarios, including earlier discharge home, complications delaying hospital discharge and the requirement for admission to a rehabilitation unit. Discharge home earlier than anticipated and discharge home rather than to a rehabilitation facility were both rated as important (median score = 5). Empirical data on the minimal clinically important difference for DAH₃₀ may be useful to determine sample size and to guide the non-inferiority margin for future clinical trials.

The impact of COVID-19 critical illness on new disability, functional outcomes and return to work at 6 months: a prospective cohort study

BACKGROUND

There are few reports of new functional impairment following critical illness from COVID-19. We aimed to describe the incidence of death or new disability, functional impairment and changes in health-related quality of life of patients after COVID-19 critical illness at 6 months.

METHODS

In a nationally representative, multicenter, prospective cohort study of COVID-19 critical illness, we determined the prevalence of death or new disability at 6 months, the primary outcome. We measured mortality, new disability and return to work with changes in the World Health Organization Disability Assessment Schedule 2.0 12L (WHODAS) and health status with the EQ5D-5LTM.

RESULTS

Of 274 eligible patients, 212 were enrolled from 30 hospitals. The median age was 61 (51-70) years, and 124 (58.5%) patients were male. At 6 months, 43/160 (26.9%) patients died and 42/108 (38.9%) responding survivors reported new disability. Compared to pre-illness, the WHODAS percentage score worsened (mean difference (MD), 10.40% [95% CI 7.06-13.77]; p < 0.001). Thirteen (11.4%) survivors had not returned to work due to poor health. There was a decrease in the EQ-5D-5LTM utility score (MD, - 0.19 [- 0.28 to - 0.10]; p < 0.001). At 6 months, 82 of 115 (71.3%) patients reported persistent symptoms. The independent predictors of death or new disability were higher severity of illness and increased frailty.

CONCLUSIONS

At six months after COVID-19 critical illness, death and new disability was substantial. Over a third of survivors had new disability, which was widespread across all areas of functioning. Clinical trial registration NCT04401254 May 26, 2020.

Core Outcome Measures for Perioperative and Anaesthetic Care (COMPAC): a modified Delphi process to develop a core outcome set for trials in perioperative care and anaesthesia

BACKGROUND

Outcome selection underpins clinical trial interpretation. Inconsistency in outcome selection and reporting hinders comparison of different trials' results, reducing the utility of research findings.

METHODS

We conducted an iterative consensus process to develop a set of Core Outcome Measures for Perioperative and Anaesthetic Care (COMPAC), following the established Core Outcome Measures for Effectiveness Trials (COMET) methodology. First, we undertook a systematic review of RCTs in high-impact journals to describe current outcome reporting trends. We then surveyed patients, carers, researchers, and perioperative clinicians about important outcomes after surgery. Finally, a purposive stakeholder sample participated in a modified Delphi process to develop a core outcome set for perioperative and anaesthesia trials.

RESULTS

Our systematic review revealed widespread inconsistency in outcome reporting, with variable or absent definitions, levels of detail, and temporal criteria. In the survey, almost all patients, carers, and clinicians rated clinical outcome measures critically important, but clinicians rated patient-centred outcomes less highly than patients and carers. The final core outcome set was: (i) mortality/survival (postoperative mortality, long-term survival); (ii) perioperative complications (major postoperative complications/adverse events; complications/adverse events causing permanent harm); (iii) resource use (length of hospital stay, unplanned readmission within 30 days); (iv) short-term recovery (discharge destination, level of dependence, or both); and (v) longer-term recovery (overall health-related quality of life).

CONCLUSIONS

This core set, incorporating important outcomes for both clinicians and patients, should guide outcome selection in future perioperative medicine or anaesthesia trials. Mapping these alongside standardised endpoint definitions will yield a comprehensive perioperative outcome framework.

Effects of lignocaine vs. opioids on antiplatelet activity of ticagrelor: the LOCAL trial

AIMS

We assessed the impact of intravenous fentanyl and lignocaine on the pharmacokinetics and pharmacodynamics of ticagrelor in patients with unstable angina and non-ST-elevation myocardial infarction and their procedural analgesic efficacy and safety.

METHODS AND RESULTS

Seventy patients undergoing coronary angiography with ticagrelor loading were included in the pharmacokinetic and pharmacodynamic analyses of this randomized trial. Plasma ticagrelor levels 2 h post-loading dose were significantly lower in the fentanyl arm than in the lignocaine treatment arm (598 vs. 1008 ng/mL, P = 0.014). The area under the plasma-time curves for ticagrelor (1228 vs. 2753 ng h/mL, P < 0.001) and its active metabolite (201 vs. 447 ng h/mL, P = 0.001) were both significantly lower in the fentanyl arm. Expression of activated platelet glycoprotein IIb/IIIa receptor (2829 vs. 1426 mean fluorescence intensity, P = 0.006) and P-selectin (439 vs. 211 mean fluorescence intensity, P = 0.001) was significantly higher at 60 min in the fentanyl arm. A higher proportion of patients had high on-treatment platelet reactivity in the fentanyl arm at 60 min using the Multiplate Analyzer (41% vs. 9%, P = 0.002) and 120 min using the VerifyNow (30% vs. 3%, P = 0.003) and VASP (37% vs. 6%, P = 0.002) assays. Both drugs were well tolerated with a high level of patient satisfaction.

CONCLUSIONS

Unlike fentanyl, lignocaine does not impair the bioavailability or delay the antiplatelet effect of ticagrelor. Both drugs were well tolerated and effective with a high level of patient satisfaction for procedural analgesia. Routine procedural analgesia during percutaneous coronary intervention should be reconsidered and if performed, lignocaine is a beneficial alternative to fentanyl.