RFDS Research: Aeromedical retrieval for suspected appendicitis in paediatrics patients

Date published

30 Jan 2020

Abdominal pain is a common presentation in children, and evaluation can often be challenging. The most common cause of abdominal pain requiring surgical intervention is acute appendicitis. If uncomplicated, it can be managed safely with non-operative treatment (antibiotic treatment). There is very little Australian literature on the rates of acute appendicitis. From 2017 to 2018, acute appendicitis emergency department presentations equalled 25,880 (1.0% [25,800/2,492,756]), with the most common emergency department presentation being for abdominal and pelvic pain (n=142,666), with 45,938 presentations in the 10- to 19-year-old age group.

In 2014–15, there were 40,752 hospital admissions for appendicectomy, representing 179 hospital admissions per 100,000 people, ranging from 164 per 100,000 people in South Australia to 215 in the Northern Territory. The rates tended to be highest in inner-regional areas as compared to major cities; however, it is unclear how many rural and remote people received a negative appendicectomy. We suspect that due to the low service provision of diagnostic imaging in rural and remote areas, the rates of negative appendicectomy would be higher.

Differentiating those children with abdominal pain who require surgical treatment from those who could be managed expectantly or medically can be difficult, particularly in the remote and rural context, where access to diagnostic testing is intermittent or delayed. Clinical examination has a high sensitivity and a low specificity, whilst ultrasound has a high positive  predictive value and the negative predictive value. Ultra-sound is recommended in addition to clinical examination in suspected acute appendicitis in paediatric patients, with CT scanning reserved for follow-up of equivocal results.

Ultrasound can reduce the rates of appendicectomy, with one study finding that increased rates of diagnostic imaging were associated with lower negative appendicectomy results (NARs) for all age and gender subgroups, other than children younger than 5 years. In addition, the efficacy of non-operative treatment of acute uncomplicated appendicitis has been confirmed.
However, many rural and remote areas do not have access to diagnostic imaging services. Point-of-care ultrasound is non-invasive and enables narrowing of the differential diagnoses and, in some instances, definitive diagnosis.

Furthermore, with appropriate training, a rural and remote clinician can confirm appendicitis on ultrasound, determine whether it is complicated or uncomplicated, or confirm an alternative diagnosis that does not require surgical intervention, such as mesenteric adenitis. Those with clinical signs suggestive of appendicitis, with no definitive diagnosis on point-
of-care ultrasound, require transfer to a facility with CT. If rural and remote clinicians are trained in point-of-care ultrasound to diagnose appendicitis and other causes of acute abdominal pain within their community, unnecessary emergency retrievals from a rural and remote area to an inner-regional or major city hospital can be avoided. It is important to note that it is not clear from the existing literature as to how many aeromedical retrievals are being conducted for a suspected diagnosis of appendicitis in the rural and remote paediatric population. In addition to this, it is unclear how many clinicians from these areas are trained to use point-of-care ultrasound. As such, the aim of this article was to describe the characteristics of paediatric patients who underwent an aeromedical retrieval within Australia (gender and Indigenous status) for suspected appendicitis between 1 July 2014 and 30 June 2018 (4 years).

Rural and remote populations have been identified as having low service provision of health care, as compared to major cities. Diagnostic imaging is recommended in suspected acute appendicitis in paediatric patients, to confirm the diagnosis and to differentiate complicated from uncomplicated appendicitis.

Anecdotally, we believe the provision of diagnostic imaging is significantly lower in rural and remote as compared to major cities in Australia. Future research will look at the diagnostic imaging provision in rural and remote areas, and how many rural and remote clinicians are trained and comfortable in performing point-of-care ultrasound. Although point of-care ultrasound cannot be interchanged with diagnostic ultrasound, further development of point-of-care ultrasound techniques and training of rural and remote clinicians could potentially have significant socio-economic impact. This study has highlighted that children residing in rural and remote areas are being retrieved for acute abdominal pain or suspected acute appendicitis. It has been estimated that an average aeromedical retrieval costs $8500.0 (AUD). Using this figure, the estimated cost for this population equalled $3,264,000. This figure does not consider social, in-hospital, or discharge costs and could be an underrepresentation. As such, future studies should determine total economic and social costs associated with an aeromedical retrieval. This study was limited to RFDS patient data and as such did not include other rural and remote healthcare providers. A further limitation was that we were unable to determine whether the aeromedically retrieved patient had any diagnostic imaging before the transfer, as these data were not routinely collected, however should be a topic of future studies.

Access to diagnostic imaging in the early diagnosis and management of acute appendicitis may decrease the number of retrievals, particularly for uncomplicated appendicitis, which can be managed non-operatively. The geographical location of these communities, combined with the ability and comfort of clinicians to utilise diagnostic imaging and point-of-care ultrasound competently and confidently for their young patients, when available, continues to provide some challenges due to the opportunity occurring on a rare and sporadic basis. Future research will provide capacity-building awareness for remote geographical service providers to improve access and training for their clinicians in point-of-care ultrasound. This will allow for earlier access to critical additional clinical information to enable more accurate patient diagnosis and improved outcomes for paediatric patients.

Read the Full Article Here: https://www.researchgate.net/p...

Harwood, Abby & Black, Sarah & Sharma, Pritish & Bishop, Lara & Gardiner, Fergus. (2020). Aeromedical retrieval for suspected appendicitis in rural and remote paediatric patients. Australasian Journal of Ultrasound in Medicine. 23. 10.1002/ajum.12198.