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.

Postoperative systemic inflammation after major abdominal surgery: patient-centred outcomes.

Postoperative systemic inflammation is strongly associated with surgical outcomes, but its relationship with patient-centred outcomes is largely unknown. Detection of excessive inflammation and patient and surgical factors associated with adverse patient-centred outcomes should inform preventative treatment options to be evaluated in clinical trials and current clinical care. This retrospective cohort study analysed prospectively collected data from 3000 high-risk, elective, major abdominal surgery patients in the restrictive vs. liberal fluid therapy for major abdominal surgery (RELIEF) trial from 47 centres in seven countries from May 2013 to September 2016. The co-primary endpoints were persistent disability or death up to 90 days after surgery, and quality of recovery using a 15-item quality of recovery score at days 3 and 30. Secondary endpoints included: 90-day and 1-year all-cause mortality; septic complications; acute kidney injury; unplanned admission to intensive care/high dependency unit; and total intensive care unit and hospital stays. Patients were assigned into quartiles of maximum postoperative C-reactive protein concentration up to day 3, after multiple imputations of missing values. The lowest (reference) group, quartile 1, C-reactive protein ≤ 85 mg.l-1 , was compared with three inflammation groups: quartile 2 > 85 mg.l-1 to 140 mg.l-1 ; quartile 3 > 140 mg.l-1 to 200 mg.l-1 ; and quartile 4 > 200 mg.l-1 to 587 mg.l-1 . Greater postoperative systemic inflammation had a higher adjusted risk ratio (95%CI) of persistent disability or death up to 90 days after surgery, quartile 4 vs. quartile 1 being 1.76 (1.31-2.36), p < 0.001. Increased inflammation was associated with increasing decline in risk-adjusted estimated medians (95%CI) for quality of recovery, the quartile 4 to quartile 1 difference being -14.4 (-17.38 to -10.71), p < 0.001 on day 3, and -5.94 (-8.92 to -2.95), p < 0.001 on day 30. Marked postoperative systemic inflammation was associated with increased risk of complications, poor quality of recovery and persistent disability or death up to 90 days after surgery.

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.

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.

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.

More than just morbidity and mortality - quality of recovery and long-term functional recovery after surgery.

Traditional surgical outcome measures include minor and major complications, hospital length of stay and sometimes longer-term survival. Each of these is important but there needs to be greater emphasis on patient-reported outcome measures. Global measures of a patient's quality of recovery, avoidance of postoperative morbidities, early hospital discharge to home (without re-admission) and longer term disability-free survival can better define postoperative recovery. A patient's recovery pathway can be mapped through the immediate days or weeks after surgery with documentation of morbidity using the postoperative morbidity survey and/or a quality of recovery score, days alive and at home up to 30 days after surgery and then longer term disability-free survival using the WHO Disability Assessment Schedule 2.0 scale. These can be used to define quality of recovery after surgery.

Postoperative recovery: the importance of the team.

An ageing population and rising healthcare costs are challenging cost-efficient hospital systems wanting to adapt, employing novel organisational structures designed to merge diverse skill sets. This needs not only physician and nursing leadership but also new models of care. Anaesthetists have expanded their role into the broader multidisciplinary field of peri-operative medicine, emphasising collaboration and safety in health teams. A greater focus on patient-centred care and shared decision making, along with validated metrics to quantify quality improvement activities, have emphasised the importance of comfort, patient satisfaction and quality of life after surgery. Shared decision-making is more likely to be manifest in a flat hierarchy in which each member of the team brings their own experience and skills to optimise patient care. Successful surgery is best achieved by a coordinated, multidisciplinary team, embedded in a culture of collaboration and safety.

Integration of the Duke Activity Status Index into preoperative risk evaluation: a multicentre prospective cohort study.

BACKGROUND: The Duke Activity Status Index (DASI) questionnaire might help incorporate self-reported functional capacity into preoperative risk assessment. Nonetheless, prognostically important thresholds in DASI scores remain unclear. We conducted a nested cohort analysis of the Measurement of Exercise Tolerance before Surgery (METS) study to characterise the association of preoperative DASI scores with postoperative death or complications. METHODS: The analysis included 1546 participants (≥40 yr of age) at an elevated cardiac risk who had inpatient noncardiac surgery. The primary outcome was 30-day death or myocardial injury. The secondary outcomes were 30-day death or myocardial infarction, in-hospital moderate-to-severe complications, and 1 yr death or new disability. Multivariable logistic regression modelling was used to characterise the adjusted association of preoperative DASI scores with outcomes. RESULTS: The DASI score had non-linear associations with outcomes. Self-reported functional capacity better than a DASI score of 34 was associated with reduced odds of 30-day death or myocardial injury (odds ratio: 0.97 per 1 point increase above 34; 95% confidence interval [CI]: 0.96-0.99) and 1 yr death or new disability (odds ratio: 0.96 per 1 point increase above 34; 95% CI: 0.92-0.99). Self-reported functional capacity worse than a DASI score of 34 was associated with increased odds of 30-day death or myocardial infarction (odds ratio: 1.05 per 1 point decrease below 34; 95% CI: 1.00-1.09), and moderate-to-severe complications (odds ratio: 1.03 per 1 point decrease below 34; 95% CI: 1.01-1.05). CONCLUSIONS: A DASI score of 34 represents a threshold for identifying patients at risk for myocardial injury, myocardial infarction, moderate-to-severe complications, and new disability.

Systematic review and consensus definitions for the Standardised Endpoints in Perioperative Medicine initiative: patient-centred outcomes.

BACKGROUND: Patient-centred outcomes are increasingly used in perioperative clinical trials. The Standardised Endpoints in Perioperative Medicine (StEP) initiative aims to define which measures should be used in future research to facilitate comparison between studies and to enable robust evidence synthesis. METHODS: A systematic review was conducted to create a longlist of patient satisfaction, health-related quality of life, functional status, patient well-being, and life-impact measures for consideration. A three-stage Delphi consensus process involving 89 international experts was then conducted in order to refine this list into a set of recommendations. RESULTS: The literature review yielded six patient-satisfaction measures, seven generic health-related quality-of-life measures, eight patient well-being measures, five functional-status measures, and five life-impact measures for consideration. The Delphi response rates were 92%, 87%, and 100% for Rounds 1, 2, and 3, respectively. Three additional measures were added during the Delphi process as a result of contributions from the StEP group members. Firm recommendations have been made about one health-related quality-of-life measure (EuroQol 5 Dimension, five-level version with visual analogue scale), one functional-status measure (WHO Disability Assessment Schedule version 2.0, 12-question version), and one life-impact measure (days alive and out of hospital at 30 days after surgery). Recommendations with caveats have been made about the Bauer patient-satisfaction measure and two life-impact measures (days alive and out of hospital at 1 yr after surgery, and discharge destination). CONCLUSIONS: Several patient-centred outcome measures have been recommended for use in future perioperative studies. We suggest that every clinical study should consider using at least one patient-centred outcome within a suite of endpoints.

Evidence for compromised data integrity in studies of liberal peri-operative inspired oxygen.

In 2016 the World Health Organization recommended intra-operative ventilation with 80% inspired oxygen to reduce surgical site infection rates, based upon a meta-analysis of 15 randomised controlled trials, of which two were by Mario Schietroma's research group. Five trials by this group have been retracted for duplication, plagiarism, statistical error and lack of ethical approval. We analysed 40 papers by this group: 24 randomised controlled trials (5064 participants) and 16 observational studies (1847 patients). There was evidence that data integrity was compromised in 38 out of the 40 analysed papers. The distribution of baseline characteristics in randomised controlled trials was unlikely, p = 1.5 × 10-8 : continuous variables within trials were heterogeneous, p = 1.9 × 10-9 , and categorical variables were homogeneous, p = 8.5 × 10-20 . Effects of interventions varied less than expected between studies: for categorical variables, for instance postoperative wound infection, p < 1 × 10-7 , and for continuous variables, for instance HLA-DR concentration, p = 0.00001. Of 184 calculable p values, for baseline variables or results, 179 (98%) were incorrect, ranging from three orders of magnitude too small to 10 orders of magnitude too large. Twenty-one graphs occurred 81 times in 23 out of 40 papers. Liberal peri-operative oxygen did not reduce surgical site infection in a meta-analysis of 20 trials that excluded seven trials by Mario Schietroma and colleagues (odds ratio (95%CI) 0.89 (0.73-1.08); p = 0.23). An update by the World Health Organization has now excluded trials of liberal oxygen by Schietroma's group, four of which have not been retracted. We conclude that Mario Schietroma's work should not inform practice until investigated.

Using the 6-minute walk test to predict disability-free survival after major surgery.

BACKGROUND: The 6-min walk test (6MWT) is a common means of functional assessment. Its relationship to disability-free survival (DFS) is uncertain. METHODS: This sub-study of the Measurement of Exercise Tolerance for Surgery study had co-primary outcome measures: correlation of the preoperative 6MWT distance with 30 day quality of recovery (15-item quality of recovery) and 12 month WHO Disability Assessment Schedule scores. The prognostic utility of the 6MWT and other risk assessment tools for 12 month DFS was assessed with logistic regression and receiver-operating-characteristic-curve analysis. RESULTS: Of 574 patients recruited, 567 (99%) completed the 6MWT. Twelve months after surgery, 16 (2.9%) patients had died and 444 (77%) had DFS. The 6MWT correlated weakly with 30 day 15-item quality of recovery (ρ=0.14; P=0.001) and 12 month WHO Disability Assessment Schedule (ρ=-0.23; P<0.0005) scores. When the cohort was split into 6MWT distance tertiles, the adjusted odds ratio of low vs high tertiles for DFS was 3.13 [95% confidence interval (CI): 1.54-6.35]. The only independent variable predictive of DFS was the Duke Activity Status Index (DASI) score (adjusted odds ratio: 1.06; P<0.0005). The area under the receiver-operating-characteristic curve for DFS was 0.63 (95% CI: 0.57-0.70) for the 6MWT, 0.60 (95% CI: 0.53-0.67) for cardiopulmonary-exercise-testing-derived peak oxygen consumption, and 0.70 (95% CI: 0.64-0.76) for the DASI score. CONCLUSIONS: Of the risk assessment tools analysed, the DASI was the most predictive of DFS. The 6MWT was safe and comparable with cardiopulmonary exercise testing for all predictive assessments. Future research should aim to determine the optimal 6MWT distance thresholds for risk prediction.

Systematic review and consensus definitions for the Standardised Endpoints in Perioperative Medicine (StEP) initiative: renal endpoints.

BACKGROUND: Renal injury is a common perioperative complication. The adoption of renal endpoints, standardised and valid for use in perioperative clinical trials, would enhance the quality of perioperative clinical research. The Standardised Endpoints in Perioperative Medicine (StEP) initiative was established to derive standardised endpoints for use in perioperative clinical trials. METHODS: A systematic review was conducted to identify renal endpoints currently reported in perioperative clinical trials. In parallel, an initial list of candidate endpoints was developed based on renal theme group expertise. A multi-round Delphi consensus process was used to refine this list and produce a suite of recommended perioperative renal outcome measures. RESULTS: Based on our systematic review, 63 studies were included for analysis. Marked heterogeneity and imprecision of endpoint definitions were observed. Our initial list of candidate endpoints included 10 endpoints for consideration. The response rates for Delphi rounds 1, 2, and 3 were 89% (n=16), 90% (n=75), and 100% (n=6), respectively. A final list of four renal endpoints was identified: acute kidney injury defined by the Kidney Disease: Improving Global Outcomes (KDIGO) consensus criteria, acute kidney disease defined by ≥30% decline in estimated glomerular filtration rate from baseline at 30 days after operation in patients meeting the acute-kidney-injury criteria within 7 days of surgery, the composite of death or renal replacement therapy, and the Major Adverse Kidney Events (MAKE) composite. CONCLUSIONS: We identified four key renal outcome measures that should be considered for use in perioperative clinical trials. Using standardised definitions to capture and report these endpoints will facilitate improved benchmarking and meta-analysis of future trials.

Systematic review and consensus definitions for standardised endpoints in perioperative medicine: postoperative cancer outcomes.

BACKGROUND: The Standardising Endpoints for Perioperative Medicine group was established to derive an appropriate set of endpoints for use in clinical trials related to anaesthesia and perioperative medicine. Anaesthetic or analgesic technique during cancer surgery with curative intent may influence the risk of recurrence or metastasis. However, given the current equipoise in the existing literature, prospective, randomised, controlled trials are necessary to test this hypothesis. As such, a cancer subgroup was formed to derive endpoints related to research in onco-anaesthesia based on a current evidence base, international consensus and expert guidance. METHODS: We undertook a systematic review to identify measures of oncological outcome used in the oncological, surgical, and wider literature. A multiround Delphi consensus process that included up to 89 clinician-researchers was then used to refine a recommended list of endpoints. RESULTS: We identified 90 studies in a literature search, which were the basis for a preliminary list of nine outcome measures and their definitions. A further two were added during the Delphi process. Response rates for Delphi rounds one, two, and three were 88% (n=9), 82% (n=73), and 100% (n=10), respectively. A final list of 10 defined endpoints was refined and developed, of which six secured approval by ≥70% of the group: cancer health related quality of life, days alive and out of hospital at 90 days, time to tumour progression, disease-free survival, cancer-specific survival, and overall survival (and 5-yr overall survival). CONCLUSION: Standardised endpoints in clinical outcomes studies will support benchmarking and pooling (meta-analysis) of trials. It is therefore recommended that one or more of these consensus-derived endpoints should be considered for inclusion in clinical trials evaluating a causal effect of anaesthesia-analgesia technique on oncological outcomes.

The early in-vivo effects of a single anti-emetic dose of dexamethasone on innate immune cell gene expression and activation in healthy volunteers.

Dexamethasone is often administered to surgical patients for anti-emetic prophylaxis. This study examined the early (up to 24 h) in-vivo effects of dexamethasone (8 mg) to demonstrate the magnitude and temporal nature of changes on circulating peripheral blood mononuclear cell gene expression and activation in 10 healthy male volunteers. Blood samples were drawn at baseline, 2 h, 4 h and 24 h. Gene expression was measured using quantitative real-time polymerase chain reaction. Cytokine expression was measured using multiplex immuno-assays. Innate immune cell phenotypes were examined with flow cytometry. Dexamethasone resulted in rapid transient changes in immunophilin (p = 0.0247), plasminogen activator inhibitor-1 (p = 0.0004), forkhead box P3 (p = 0.0068) and dual specific phosphatase-1 (p = 0.0157) gene expression at 4 h compared with pre-dexamethasone. Plasma interleukin-10 levels increased within 2 h (p = 0.0071) and returned to baseline at 24 h. Reductions in classical (p = 0.0009) and intermediate monocytes (p = 0.0178) and dendritic cells (p = 0.0012) were followed by increases in the level of these populations at 24 h compared with pre-dexamethasone (classical monocytes p = 0.0073, intermediate monocytes p = 0.0271, dendritic cells p = 0.0142). There was a profound reduction in the mean fluorescence intensity of the maturation marker, human histocompatibility leucocyte antigen, at 24 h in all monocyte subsets (p = 0.0002 for classical and non-classical monocytes, p = 0.0001 for intermediate monocytes) and dendritic cells (p = 0.0001). This study confirms rapid transient effects of 8 mg dexamethasone on innate immune cells with the potential to alter the inflammatory response to surgery and provides support for the hypothesis that intra-operative administration may be both immunosuppressive and immune-activating in the immediate peri-operative period.

Systematic review and consensus definitions for the Standardised Endpoints in Perioperative Medicine (StEP) initiative: patient comfort.

BACKGROUND: Maximising patient comfort during and after surgery is a primary concern of anaesthetists and other perioperative clinicians, but objective measures of what constitutes patient comfort in the perioperative period remain poorly defined. The Standardised Endpoints in Perioperative Medicine initiative was established to derive a set of standardised endpoints for use in perioperative clinical trials. METHODS: We undertook a systematic review to identify measures of patient comfort used in the anaesthetic, surgical, and other perioperative literature. A multi-round Delphi consensus process that included up to 89 clinician researchers was then used to refine a recommended list of outcome measures. RESULTS: We identified 122 studies in a literature search, which were the basis for a preliminary list of 24 outcome measures and their definitions. The response rates for Delphi Rounds 1, 2, and 3 were 100% (n=22), 90% (n=79), and 100% (n=13), respectively. A final list of six defined endpoints was identified: pain intensity (at rest and during movement) at 24 h postoperatively, nausea and vomiting (0-6 h, 6-24 h, and overall), one of two quality-of-recovery (QoR) scales (QoR score or QoR-15), time to gastrointestinal recovery, time to mobilisation, and sleep quality. CONCLUSIONS: As standardised outcomes will support benchmarking and pooling (meta-analysis) of trials, one or more of these recommended endpoints should be considered for inclusion in clinical trials assessing patient comfort and pain after surgery.

Age and other perioperative risk factors for postoperative systemic inflammatory response syndrome after cardiac surgery.

BACKGROUND: The inflammatory response to surgery varies considerably between individual patients. Age might be a substantial factor in this variability. Our objective was to examine the association of patient age and other potential risk factors with the occurrence of a postoperative systemic inflammatory response syndrome, during the first 24 h after cardiac surgery. METHODS: This was a retrospective cohort study, using linked data from the Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) Database and the Australian and New Zealand Intensive Care Society (ANZICS) Adult Patient Database. Data from patients who underwent coronary artery bypass grafting and/or valve surgery were used. The association between age and postoperative SIRS was analysed using Poisson regression, and corrected for other risk factors. Restricted cubic splines were used to determine relevant age categories. Results are expressed as risk ratios (RR) with 95% confidence intervals (CI). RESULTS: Data from 28 513 patients were used. In both univariable and multivariable models, increased patient age was strongly associated with reduced postoperative SIRS prevalence. Using 73-83 yr as the reference category, the RRs (95% CI) for the age categories were 1.38 (1.28-1.49) for ≤43 yr, 1.15 (1.09-1.20) for 44-63 yr, 1.05 (1.00-1.09) for 64-72 yr, and 1.03 (0.94-1.12) for >83 yr, respectively. The predictive value for postoperative SIRS of the final model, however, was moderate (c-statistic: 0.61). CONCLUSIONS: We have demonstrated that advanced patient age is associated with a decreased risk of postoperative SIRS among cardiac surgery patients, where patients aged over 72 yr had the lowest risk.

Intra-operative protective mechanical ventilation in lung transplantation: a randomised, controlled trial.

Primary graft dysfunction occurs in up to 25% of patients after lung transplantation. Contributing factors include ventilator-induced lung injury, cardiopulmonary bypass, ischaemia-reperfusion injury and excessive fluid administration. We evaluated the feasibility, safety and efficacy of an open-lung protective ventilation strategy aimed at reducing ventilator-induced lung injury. We enrolled adult patients scheduled to undergo bilateral sequential lung transplantation, and randomly assigned them to either a control group (volume-controlled ventilation with 5 cmH2 O, positive end-expiratory pressure, low tidal volumes (two-lung ventilation 6 ml.kg-1 , one-lung ventilation 4 ml.kg-1 )) or an alveolar recruitment group (regular step-wise positive end-expiratory pressure-based alveolar recruitment manoeuvres, pressure-controlled ventilation set at 16 cmH2 O with 10 cmH2 O positive end-expiratory pressure). Ventilation strategies were commenced from reperfusion of the first lung allograft and continued for the duration of surgery. Regular PaO2 /FI O2 ratios were calculated and venous blood samples collected for inflammatory marker evaluation during the procedure and for the first 24 h of intensive care stay. The primary end-point was the PaO2 /FI O2 ratio at 24 h after first lung reperfusion. Thirty adult patients were studied. The primary outcome was not different between groups (mean (SD) PaO2 /FI O2 ratio control group 340 (111) vs. alveolar recruitment group 404 (153); adjusted p = 0.26). Patients in the control group had poorer mean (SD) PaO2 /FI O2 ratios at the end of the surgical procedure and a longer median (IQR [range]) time to tracheal extubation compared with the alveolar recruitment group (308 (144) vs. 402 (154) (p = 0.03) and 18 (10-27 [5-468]) h vs. 15 (11-36 [5-115]) h (p = 0.01), respectively). An open-lung protective ventilation strategy during surgery for lung transplantation is feasible, safe and achieves favourable ventilation parameters.

Patient and community attitudes toward perioperative biobanking and genomic research.

We surveyed hospital patients and clinicians to ascertain their attitudes to the establishment of a perioperative biobank for future genomics research, and whether the requirements for an opt-out approach to consent can be met. We enrolled hospital patients (n=187), patient spouse/family members (n=64), ethics committee members (n=14), and clinical staff (doctors and nurses [n=67]), and unspecified community members (n=10). They were asked to rate and describe their views on medical research and biobanking, the need for individual consent, and the importance of confidentiality. Of 406 survey forms distributed, 342 (84%) were returned. Nearly all participants (98%) indicated that a perioperative biobank is important, 93% were comfortable with de-identified genetic research, and 90% indicated that the hospital should be able to use leftover blood for medical research, provided the research has been approved by an ethics committee and personally identifying information has been removed. Participants were more likely to support biobanking if it used de-identified samples, and if, for this reason, their consent was not sought. Participants with chronic medical and surgical conditions were significantly more supportive and comfortable with genetic research, as were most in the hospital community. Most hospital patients, community members and clinicians are supportive of the development of a perioperative biobank used for genomic research. This supports the adoption of an opt-out approach to consent model.

Measuring acute postoperative pain using the visual analog scale: the minimal clinically important difference and patient acceptable symptom state.

Background: The 100 mm visual analog scale (VAS) score is widely used to measure pain intensity after surgery. Despite this widespread use, it is unclear what constitutes the minimal clinically important difference (MCID); that is, what minimal change in score would indicate a meaningful change in a patient's pain status. Methods: We enrolled a sequential, unselected cohort of patients recovering from surgery and used a VAS to quantify pain intensity. We compared changes in the VAS with a global rating-of-change questionnaire using an anchor-based method and three distribution-based methods (0.3 sd , standard error of the measurement, and 5% range). We then averaged the change estimates to determine the MCID for the pain VAS. The patient acceptable symptom state (PASS) was defined as the 25th centile of the VAS corresponding to a positive patient response to having made a good recovery from surgery. Results: We enrolled 224 patients at the first postoperative visit, and 219 of these were available for a second interview. The VAS scores improved significantly between the first two interviews. Triangulation of distribution and anchor-based methods resulted in an MCID of 9.9 for the pain VAS, and a PASS of 33. Conclusions: Analgesic interventions that provide a change of 10 for the 100 mm pain VAS signify a clinically important improvement or deterioration, and a VAS of 33 or less signifies acceptable pain control (i.e. a responder), after surgery.