A simple epidural simulator: a blinded study assessing the 'feel' of loss of resistance in four fruits.

CONTEXT

Complex epidural simulators are now available, but these are expensive and not widely available. Simple simulators using fruit have been described before.

OBJECTIVE

To ascertain which easily available fruit would best simulate the 'feel' of loss of resistance experienced in epidural insertion and be used as a teaching tool.

DESIGN

A single blinded study using four different fruits housed in a purpose-built box to conceal the identities of the fruits. The fruits were labelled A, B, C and D.

SETTING

Two teaching hospitals in Glasgow, Scotland between 2006 and 2007.

PARTICIPANTS

Fifty participants consisting of consultant anaesthetists, specialist registrars and senior house officers all with previous epidural experience.

INTERVENTION

Insertion of a Tuohy needle into the four concealed fruits (orange, banana, kiwi and honeydew melon). Each participant then completed a questionnaire that included recording of the realism of the 'feel' of loss of resistance of each fruit.

MAIN OUTCOME MEASURES

The 'feel' of loss of resistance for each fruit was scored on a 100-mm Visual Analogue Scale. A '0  mm' represented 'completely unrealistic feel' and '100  mm' represented 'indistinguishable feel from a real patient'.

RESULTS

A total of 62.6% of participants recorded the banana as their first choice. This result was statistically significant after taking into account the grades of the participants, their years of experience, the needle gauge used and the participants' chosen technique.

CONCLUSION

The banana is a cheap and easily available training tool to introduce novice anaesthetists to the feel of loss of resistance, which is best experienced before the first insertion of an epidural in a patient.