In their otherwise comprehensive review, Farrell and McConaghy omit to specifically discuss the management of spinal or epidural anaesthesia in patients with implanted spinal cord stimulators (SCS) or intrathecal drug delivery systems (ITDDS). As we have noted elsewhere, great care should be taken if a neuraxial block is considered, as there is a risk of damaging the SCS electrode or ITDDS catheter. However, if necessary, then it is advisable to undertake the neuraxial block utilizing fluoroscopic or ultrasound guidance to minimise this risk.[1] Inserting an epidural catheter for post-operative analgesia in a patient with a SCS in-situ also runs the risk of dislodgement or infection of the SCS electrode, in our opinion. The authors state the risks of using diathermy in patients with implanted SCS electrodes, but omit to mention that unipolar diathermy should be avoided where possible. If its use is unavoidable, the reference plate should be positioned to ensure that the SCS components are outside the electrical field of the diathermy. [2]
References:
1. Raphael JH, Mutagi HS, Kapur S. Spinal Cord Stimulation and its anaesthetic implications. British Journal of Anaesthesia Continuing Education in Anaesthesia, Critical Care & Pain 2009; 9(3): 78-81
2. Spinal cord stimulation for the management of pain: recommendations for best clinical practice. British Pain Society,2009.www.britishpainsociety.org/pub_professional.htm

Competing interests: None declared