GMGustavo Castagna Machado

Gustavo Castagna Machado

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Previous Organizations / Institutes

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Gustavo Castagna Machado has a total of 310 co-authors. Here are the top co-authors by number of shared publications:


Latest Publications

  • Open Access

    Oral oxycodone versus sublingual buprenorphine for postoperative pain control after pelvic exenteration (PROSPER): a pilot, registry-embedded, multi-centre, double-blind, placebo-controlled, randomised controlled trial

    by Charlotte Johnstone, Cherry Koh, Stephanie Mathieson, Daniel Steffens, Kate White, Paul Gray, Craig Harris, Alexander Heriot, Kaitlin Kramer, Chi Kin Law, et al.

    Objectives: This study aims to estimate the rate of recruitment of participants. Design: This is a pilot, multicentre, double-blind, placebo-controlled, randomised controlled trial of oral oxycodone and sublingual placebo vs sublingual buprenorphine and oral placebo for postoperative pain management for 7 days after pelvic exenteration. Setting: Patients will be recruited from three metropolitan quaternary referral centres that offer advanced gastrointestinal surgery in Australia. Participants: The inclusion criteria will be patients over the age of 18 years undergoing pelvic exenteration surgery and exclusion criteria are previous adverse events related to the study drugs, currently requiring monoamine oxidase inhibitor medications and if epidural analgesia is planned in the perioperative period. Interventions: Enrolled patients will undergo pelvic exenteration surgery and be initiated postoperatively on patient-controlled analgesia. In the postoperative period, when clinically appropriate to take oral medications, patients will be commenced on trial analgesia for 7 days. Participants will be randomised to receive either oral active oxycodone 5–10 mg up to 3 hourly as required (with sublingual placebo) or sublingual active buprenorphine 200–400 mcg 3 hourly as required (with oral placebo). Main outcome measures: The primary outcome measure is the rate of recruitment over a 6-month period. Secondary outcomes include an assessment of missing data, protocol adherence and acceptability of the trial to participants. Ethics and dissemination: The trial received ethics approval from Sydney Local Health District, Royal Prince Alfred Hospital Human Research Ethics Committee (No: X25-0128 & 2025/ETH01058). The results of the study will be disseminated by publication and presentation at local annual scientific meetings in Australia. Trial registration number: The study protocol is prospectively registered at the Australian New Zealand Clinical Trials Registry (ANZCTR) ( www.anzctr.org.au ; ACTRN12625000901404).

  • Open Access

    SAGE (safer analgesia): a protocol for a pragmatic cluster randomised controlled trial to reduce the use of high-risk medicines in people with chronic back and/or neck pain

    by Christina Abdel Shaheed, Andrew J McLachlan, Stephanie Mathieson, Rowena Ivers, Philip J Clare, Fiona Blyth, Fiona Stanaway, Louisa Degenhardt, Danijela Gnjidic, Simon French, et al.

    Introduction: Chronic back and neck pain are commonly treated with opioid analgesics, gabapentinoids and benzodiazepines, despite their high-risk profile and potential limited efficacy. Deprescribing interventions (aimed at medicine reduction or cessation) have shown some effectiveness in reducing the use of these medications, but similar approaches tailored to individuals with complex chronic back and/or neck pain are lacking and urgently needed. This trial will evaluate the effect of the safer analgesia (SAGE) intervention (training of general practitioners (GPs) in deprescribing and support to deprescribe) on cessation and/or reduction of the target high-risk medicine (a benzodiazepine, gabapentinoid or opioid) for people with chronic back and/or neck pain. Methods and analysis: SAGE is a pragmatic cluster randomised trial that will be conducted with at least 30 general practices in Australia randomly assigned in a 1:1 ratio to the SAGE intervention or no intervention (usual care control group). The SAGE intervention is a GP-facing intervention comprising (i) training for GPs in deprescribing and access to deprescribing resources and (ii) deprescribing support—to assist the deprescribing process for their patients, GPs can conduct a long GP consultation (20–40-min duration), refer to trained physiotherapists for the provision of psychologically informed physiotherapy sessions and provide alternate pain management options including heat wrap and diclofenac gel. A total of 320 adult patient-participants experiencing chronic back and/or neck pain (≥ 3 months duration) prescribed a target high-risk medicine (benzodiazepine, gabapentinoid or opioid) persistently for this pain will be recruited via participating general practices. The primary outcome is cessation of dispensation of the trial participant’s high-risk medicine (a benzodiazepine, gabapentinoid or opioid) prescribed by their trial GP. The primary time-point for the primary outcome will be 1-year post-enrolment with an observation window of the preceding 4 weeks. Secondary outcomes include self-reported outcomes such as pain, quality of life and adverse events. Analyses will follow an intention-to-treat approach with a nested economic evaluation and per-protocol analysis planned separately. Ethics and dissemination: The study received approval from the University of Sydney Human Research Ethics Committee (2024/HE001706). The results will be disseminated via publication in a peer-reviewed scientific journal, presentation at conferences and media. Trial registration number: ANZCTR: ACTRN12625000953437.

  • Open Access

    Effectiveness of primary-contact physiotherapy in managing musculoskeletal conditions in emergency departments: Statistical analysis plan for the RESHAP-ED randomised controlled trial

    by Sana Shan, Laurent Billot, Gustavo Machado, Christopher Maher

    The RESHAP-ED 1 trial is a pragmatic, multicentre, two-arm, parallel randomised controlled trial which aims to test the effectiveness of primary-contact physiotherapy for musculoskeletal pain when compared to the traditional doctor/nurse pathway, on patient flow (i.e. length of stay) in the emergency department. The objective of this trial is to compare two approaches to physiotherapy involvement in the assessment and management of patients who present to emergency departments with simple musculoskeletal problems that are both standard of care in Australian emergency departments. The primary health services outcome is emergency department length of stay defined as the period between when a patient presents at an emergency department, and when that person is recorded as having physically departed the emergency department. The primary outcome will be analysed using a generalised linear mixed effects model with a fixed effect of intervention (primary-contact physiotherapy vs control) and a random effect for hospital. The statistical analysis plan pre-specifies the method of analysis for primary, secondary and safety outcomes and key variables collected in the trial. Secondary, and subgroup group analyses have been pre-specified as well.

  • Impact of strategies to improve flow and lower hospital admissions for low back pain in the emergency department: an interrupted time-series analysis

    by Simon R E Davidson, Steven Kamper, Robin Haskins, Dragan Petkovic, Nicole Feenan, Damien Smith, Michael O’FLynn, Jeremy D Pallas, Bruce Donald, John Paul Smiles, et al.

    Background Low back pain (LBP) is a common, disabling condition that often results in presentation to the emergency department (ED). There is currently a paucity of research examining how to optimise care for this patient group and concurrently improve service efficiency. We assessed the impact of a suite of co-designed strategies to improve the flow and reduce admission rate of people with LBP presenting to the ED. Methods A quasi-experimental implementation science study in a 30-bed ED at an Australian tertiary referral hospital. We implemented four improvement strategies: (1) co-design and development of a local ED guideline, (2) patient handout, (3) clinician education programme and (4) rapid-access physiotherapy follow-up clinic. We included all ED presentations from patients ≥16 years old, with a final diagnosis of LBP. Using an interrupted time series analysis, we compared a pre-implementation phase (July 2014–December 2019), a transition phase (July 2020–February 2021) and a post implementation phase (March 2021–November 2021). Our primary outcome was the proportion of patients admitted to hospital, in each phase. Secondary outcomes included ED length of stay (LOS), ED presentation cost, re-presentations within five days, admission LOS and outcome measures for those patients who attended the rapid-access physiotherapy clinic. Results There were 5301 LBP presentations pre-implementation, 752 during transition and 732 post implementation. The mean age of patients was 50.3 (20.1) years, 53% were female and 6.5% identified as Aboriginal and/or Torres Strait Islander. We observed a small reduction (2%) in the proportion of admissions per month (post implementation vs pre-implementation slope difference 0.98 ((95% CI 0.928 to 1.035), p=0.467) and a monthly decrease of 1.5 min in the average ED LOS for these patients (post implementation vs pre-implementation slope difference −1.5 ((95% CI −8.1 to 5.1), p=0.653) which was not statistically significant. 121 patients were referred to the follow-up physiotherapy clinic, and 41% attended an appointment. Conclusion The improvement strategies did not significantly reduce admissions or LOS for people with LBP presenting to the ED, and based on the CIs, we cannot exclude that these increased.


  • Open Access

    Pathology testing for patients with low back pain in Australian emergency departments

    by Claudia Côté-Picard, Qiuzhe Chen, Hugo Massé-Alarie, Peter Youssef, Michael Spies, Chris G Maher, Gustavo C Machado

    Background Imaging in low back pain management is well documented, but little is known about pathology testing in this population. We aimed to describe the profile of patients with low back pain who received pathology testing in emergency departments, and to describe the ordered tests. Methods A retrospective study of electronic medical records from three emergency departments in Sydney, New South Wales, Australia, from January 2016 to October 2021, was undertaken. We included patients diagnosed with a lumbar spine condition at discharge from the emergency department and extracted their demographic and episode of care characteristics. We performed logistic regressions adjusted for age, sex and triage category to identify the factors associated with pathology testing. Results Pathology tests were ordered in 23.8% of 15 300 episodes of care. Patients who were admitted (adjusted odds ratio (aOR) 60.54, 95% CI 52.5, 69.81), stayed longer in the emergency department (aOR 3.76, 95% CI 3.45, 4.10), had a serious pathology (aOR 2.74, 95% CI 2.30, 3.27), or arrived by ambulance (aOR 2.64, 95% CI 2.42, 2.87), were more likely to receive a pathology test than their counterparts. Full blood count, electrolytes, urea, creatinine (EUC), and liver function tests were the most ordered tests. Conclusions The characteristics associated with pathology testing were similar to those reported for lumbar imaging in patients with low back pain in previous studies. Our results suggest that guideline recommendations for pathology testing were partly followed, but an investigation into the appropriateness of pathology testing is needed to confirm this hypothesis.

  • Open Access

    The Clinical Course of Hip and Knee Osteoarthritis in Adults Attending Two Hospital Outpatient Physiotherapy Clinics in NSW: An Evaluation of the Osteoarthritis Chronic Care Program (OACCP)

    by Alla Melman, Fred Menz, Chris Needs, Tarcisio F. de Campos, Mona Marabani, Kimberley Bostock, Rhiannon Dick, Stuart Hayes, Joshua R. Zadro, Gustavo C. Machado, et al.

    Background: Osteoarthritis (OA) affects over 700,000 individuals in NSW, with projections estimating an increase to 1 million by 2030. This has led to a significant rise in joint replacement surgeries and associated healthcare costs. Despite guidelines recommending non‐surgical care as first line treatment, many patients remain on surgical waiting lists without accessing these treatments.Aim: The aims of this study were to describe the characteristics and clinical outcomes of people with hip and knee OA attending two Sydney Local Health District (SLHD) Osteoarthritis Chronic Care Program (OACCP) clinics, and to identify whether baseline measures are associated with achieving Minimal Clinically Important (MCI) difference in outcomes.Methods: This retrospective study (n = 1402) evaluated the OACCP's implementation within two SLHD hospitals between Oct 2018 and Sept 2023, describing patient characteristics, patient reported outcomes, physical performance measures, and allied health access. Changes in clinical outcomes in the short‐term (3 months) and long‐term (12 months) assessment as well as associations of patient's baseline measures with MCI improvements in clinical outcomes were analysed.Results: Most self‐reported outcomes and physical performance measures improved at both 3 and 12 months. 38.6% of patients reached the MCI threshold for KOOS total score at 3 months, which rose to 52.1% at 12 months. None of the baseline characteristics predicted outcomes.Conclusion: Following multidisciplinary non‐surgical care, people with hip and/or knee OA experience improved quality of life and function that is sustained for up to 12 months. However, analysis was limited by low long‐term follow‐up rates and no control group.


  • NICE Standard for low back pain and sciatica needs urgent revision

    by Crystian B Oliveira, Gustavo C Machado, Martin Underwood, Chris G Maher

    In 2016, the National Institute for Health and Care Excellence (NICE) released a guideline containing evidence-based recommendations for the management of low back pain and sciatica.3 Subsequently, NICE published the Clinical Care Standard in 2017 focusing on priority areas for healthcare quality improvement for the management of low back pain and sciatica.4 The NICE Standard is composed of a set of ‘quality statements’ describing the high quality care that should be provided and ‘quality measures’ to assess the care specified in the statement.5 Our view, however, is that health service planners, clinicians and patients are not well served by the 2017 NICE Standard.4 In this viewpoint, we discuss the problems with the 2017 NICE Standard and suggest how the Standard could be revised so that it better reflects the current evidence and provides more helpful guidance for clinicians. The evidence of the effectiveness of the interventions discussed in this viewpoint is provided in online supplemental file 1.