REDDISH: REDucing Delays In aneurysmal Subarachnoid Haemorrhage

Chief Investigator: Associate Professor Seana Gall

Aneurysmal subarachnoid haemorrhage (aSAH) is a rare but devastating form of stroke caused by a ruptured brain aneurysm that kills at least 30% of sufferers within 1 month.(1) Many survivors are disabled and its lifetime costs are up to 3 times that of ischaemic stroke.(2, 3)

Survival and functional outcomes can be improved through rapid access to specialised radiological, surgical and intensive care facilities. In previous studies there are reports of significant delays in receiving treatment for aSAH.(4, 5) These delays are contributing to the poor outcomes observed but we currently have a very limited understanding of the causes of these delays.(5, 6)

By understanding the factors that contribute to delays in treatment and determining the optimal treatment window for aSAH we can then develop interventions to reduce delays and ultimately improve outcomes.

We will determine the optimal window for treatment to reduce complications, improve survival and increase the proportion of people discharged home.

This study will provide the first estimates of timeliness of care for aSAH and its predictors in Australia.


  1. To quantify the time delays in treatment of aSAH for patients across Tasmania and South-East Victoria.
  2. To identify individual and health-system factors that contribute to delays in receiving treatment for aSAH.
  3. To determine the optimal treatment window to achieve the best outcomes after aSAH including fewer complications, more frequent discharges home, better functional recovery and increased survival up to 12 months after aSAH.
  4. To develop a clinical pathway in conjunction with stakeholders that can be used to reduce delays in the treatment of aSAH.


aSAH is a time critical medical emergency with many potential barriers to rapid diagnosis and treatment.

aSAH is a devastating disease affecting mostly women in their 50s and 60s.(7) It has associated direct medical costs up to 3 times larger than those associated with ischaemic stroke,(3) as well as substantial indirect costs (e.g. productivity loss and informal care giving).(2)

These outcomes could be improved, and associated costs reduced, through increased access to timely treatment. We currently lack information on the delays in presentation, diagnosis and treatment or the factors that influence these delays for aSAH in Australia, or elsewhere in the world.

Early treatment of aSAH through surgical clipping or endovascular coiling is associated with better outcomes. There is no consensus about the optimal treatment window for aSAH but receiving treatment within 24 hours (5) or 48 hours (8) is associated with fewer complications, reduced disability and greater survival than treatment after those periods. Ensuring that people with aSAH are able to access treatment at a specialised facility as soon as possible after symptom onset is important to achieve the best possible outcomes.


The REDDISH study will be conducted across Tasmania and South East Victoria covering a population of ~1.8 million and around 70,000 km2. It will focus on two major tertiary referral hospitals (Royal Hobart Hospital servicing Tasmania and the Monash Medical Centre servicing South Eastern Victoria) both being a part of a network of urban, regional and rural hospitals.

Study 1: Retrospective study of delays in treatment of aSAH

We will include cases of first-ever aSAH occurring within the referral networks of two tertiary hospitals between 2010 and 2016. Data will extracted on individual factors, pre-hospital factors, and hospital factors from the digital medical records of eligible cases.

Study 2: Qualitative study of the factors impacting on time to treatment following aSAH

The purpose of the qualitative study is to provide further understanding of the factors contributing to delays in receiving treatment for aSAH.

We will use a multiple case study approach (11). The study will include the person with aSAH, the family member or friend with the patient at the time of the episode, the health professional who was the first point of contact with the patient and the person responsible for definitive treatment.

Study 3: Development of a clinical pathway to reduce delays in aSAH

The aim of Study 3 is to use the data on the drivers of delays in receiving treatment to develop a clinical pathway for aSAH patients that can be used to reduce times to treatment.

Stakeholders will identify and prioritise recommendations to minimise time to treatment for aSAH patients and optimise access to neurosurgical and neuroradiological interventions.

Outcomes, significance and innovation

REDDISH is the first comprehensive study of treatment delays in aSAH. Our mixed methods study will provide rich data on the sources of delays allowing us to develop a clinical pathway that can reduce delays and, ultimately, improve outcomes.

Through the development of a clinical pathway we will achieve our goal of rapid diagnosis and treatment for all people with aSAH irrespective of where they live or the severity of their event.

The REDDISH study will result in improvements in the outcomes of this devastating disease, which today still kills at least 30% of sufferers who are largely people in their 50s and 60s in the prime of their lives.

The team

Seana Gall
Amanda Thrift
Leigh Kinsman
Karen Smith
Christopher Blizzard
Christine Stirling
Ronil Chandra

Associate Investigators
Hamid Asadi
Michele Callisaya
Leon Lai
Ian Mosely
Linda Nichols
Mathew Reeves
Nova Thani
Gemma Kitsos
Sabah Rehman
Susan Mosley


Jens Froelich


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  10. Connolly ES, Jr., Rabinstein AA, Carhuapoma JR, Derdeyn CP, Dion J, Higashida RT, et al. Guidelines for the management of aneurysmal subarachnoid hemorrhage: a guideline for healthcare professionals from the American Heart Association/american Stroke Association. Stroke. 2012;43(6):1711-37.
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