Understanding disparities in post-operative mortality for Indigenous patients.

There is an urgent need for high-quality evidence regarding post-operative mortality among Indigenous peoples. Our group recently published a national audit of 4,000,000 procedures conducted between 2005-2017, which identified considerable disparities in post-operative mortality between Indigenous Maori and non-Indigenous New Zealanders. Understanding the primary drivers of these disparities-for Maori, but likely also other Indigenous populations worldwide-requires us to consider the multiple levels at which these drivers might arise. To that end, in this paper we breakdown these drivers in detail, conceptualising these drivers as operating in layers with each factor leading to the next. These layers include structural factors, care system factors, care process factors, care team factors and patient factors. Each of these factors are presented within a framework that can be used to begin to understand them - with a view to rousing action and inspiring intervention to address inequities in post-operative outcomes experienced by Indigenous peoples.

Regional variation in post-operative mortality in New Zealand.

BACKGROUND: There is a growing body of evidence that access to best practice perioperative care varies within our population. In this study, we use national-level data to begin to address gaps in our understanding of regional variation in post-operative outcomes within New Zealand. METHODS: Using National Collections data, we examined all inpatient procedures in New Zealand public hospitals between 2005 and 2017 (859 171 acute, 2 276 986 elective/waiting list), and identified deaths within 30 days. We calculated crude and adjusted rates per 100 procedures for the 20 district health boards (DHBs), both for the total population and stratified by ethnicity (Maori/European). Odds ratios comparing the risk of post-operative mortality between Maori and European patients were calculated using crude and adjusted Poisson regression models. RESULTS: We observed regional variations in post-operative mortality outcomes. Maori, compared to European, patients experienced higher post-operative mortality rates in several DHBs, with a trend to higher mortality in almost all DHBs. Regional variation in patterns of age, procedure, deprivation and comorbidity (in particular) largely drives regional variation in post-operative mortality, although variation persists in some regions even after adjusting for these factors. Inequitable outcomes for Maori also persist in several regions despite adjustment for multiple factors, particularly in the elective setting. CONCLUSIONS: The persistence of variation and ethnic disparities in spite of adjustment for confounding and mediating factors suggests that multiple regions require additional resource and support to improve outcomes. Efforts to reduce variation and improve outcomes for patients will require both central planning and monitoring, as well as region-specific intervention.

Anaesthetic choice for hip or knee arthroplasty in New Zealand: Risk of postoperative death and variations in use.

Anaesthetic choice for large joint surgery can impact postoperative outcomes, including mortality. The extent to which the impact of anaesthetic choice on postoperative mortality varies within patient populations and the extent to which anaesthetic choice is changing over time remain under-explored both internationally and in the diverse New Zealand context. In a national study of 199,211 hip and knee replacement procedures conducted between 2005 and 2017, we compared postoperative mortality among those receiving general, regional or general plus regional anaesthesia. Focusing on unilateral (n=86,467) and partial (n=13,889) hip replacements, we assessed whether some groups within the population are more likely to receive general, regional or general plus regional anaesthesia than others, and whether mortality risk varies depending on anaesthetic choice. We also examined temporal changes in anaesthetic choice over time. Those receiving regional alone or general plus regional for unilateral hip replacement appeared at increased risk of 30-day mortality compared to general anaesthesia alone, even after adjusting for differences in terms of age, ethnicity, deprivation, rurality, comorbidity, American Society of Anesthesiologists physical status score and admission type (e.g. general plus regional: adjusted hazard ratio (adj. HR)=1.94, 95% confidence intervals (CI) 1.32 to 2.84). By contrast, we observed lower 30-day mortality among those receiving regional anaesthesia alone compared to general alone for partial hip replacement (adj. HR=0.86, 95% CI 0.75 to 0.97). The latter observation contrasts with declining temporal trends in the use of regional anaesthesia alone for partial hip replacement procedures. However, we recognise that postoperative mortality is one perioperative factor that drives anaesthetic choice.

Disparities in post-operative mortality between Maori and non-Indigenous ethnic groups in New Zealand.

AIM: To describe disparities in post-operative mortality experienced by Indigenous Maori compared to non-Indigenous New Zealanders. METHODS: We completed a national study of all those undergoing a surgical procedure between 2005 and 2017 in New Zealand. We examined 30-day and 90-day post-operative mortality for all surgical specialties and by common procedures. We compared age-standardised rates between ethnic groups (Maori, Pacific, Asian, European, MELAA/Other) and calculated hazard ratios (HRs) using Cox proportional hazards regression modelling adjusted for age, sex, deprivation, rurality, comorbidity, ASA score, anaesthetic type, procedure risk and procedure specialty. RESULTS: From nearly 3.9 million surgical procedures (876,976 acute, 2,990,726 elective/waiting list), we observed ethnic disparities in post-operative mortality across procedures, with the largest disparities occurring between Maori and Europeans. Maori had higher rates of 30- and 90-day post-operative mortality across most broad procedure categories, with the disparity between Maori and Europeans strongest for elective/waiting list procedures (eg, elective/waiting list musculoskeletal procedures, 30-day mortality: adj. HR 1.93, 95% CI 1.56-2.39). CONCLUSIONS: The disparities we observed are likely driven by a combination of healthcare system, process and clinical team factors, and we have presented the key mechanisms within these factors.

Postoperative mortality in New Zealand following general anaesthetic: demographic patterns and temporal trends.

OBJECTIVES: In this manuscript, we describe broad trends in postoperative mortality in New Zealand (a country with universal healthcare) for acute and elective/waiting list procedures conducted between 2005 and 2017. DESIGN, PARTICIPANTS AND SETTING: We use high-quality national-level hospitalisation data to compare the risk of postoperative mortality between demographic subgroups after adjusting for key patient-level confounders and mediators. We also present temporal trends and consider how rates in postoperative death following acute and elective/waiting list procedures have changed over this time period. RESULTS AND CONCLUSION: A total of 1 836 683 unique patients accounted for 3 117 374 admissions in which a procedure was performed under general anaesthetic over the study period. We observed an overall 30-day mortality rate of 0.5 per 100 procedures and a 90-day mortality rate of 0.9 per 100. For acute procedures, we observed a 30-day mortality rate of 1.6 per 100, compared with 0.2 per 100 for elective/waiting list procedures. In terms of procedure specialty, respiratory and cardiovascular procedures had the highest rate of 30-day mortality (age-standardised rate, acute procedures: 3-6 per 100; elective/waiting list: 0.7-1 per 100). As in other contexts, we observed that the likelihood of postoperative death was not proportionally distributed within our population: older patients, Maori patients, those living in areas with higher deprivation and those with comorbidity were at increased risk of postoperative death, even after adjusting for all available factors that might explain differences between these groups. Increasing procedure risk (measured using the Johns Hopkins Surgical Risk Classification System) was also associated with an increased risk of postoperative death. Encouragingly, it appears that risk of postoperative mortality has declined over the past decade, possibly reflecting improvements in perioperative quality of care; however, this decline did not occur equally across procedure specialties.

Pain images: hip pain--wrong diagnosis, wrong operation.

OBJECTIVE: The clinical presentation of retroperitoneal schwannoma with neuropathic pain and its subsequent management is presented. DESIGN AND SETTING: This is a case report of a 67-year-old woman who developed left hip pain radiating into the postero-lateral portion of her left thigh and extending to the knee. INTERVENTION: The patient underwent a left hip replacement for suspected pain from osteoarthritis of the hip joint. OUTCOME MEASURE: The location of her pain was unchanged from the initial presentation, and more extensive investigations were carried out. RESULT: The pain was found to be neuropathic in nature caused by a 54 mm retroperitoneal schwannoma. CONCLUSION: Our case demonstrates the principle that unless the diagnosis is very clear (based on history, examination and diagnostic local anaesthetic injection, and confirmed by special investigations), surgery should not be considered. Where doubt exists, further assessment and investigation is required.