Needle‐through‐Quincke needle technique for establishing spinal anaesthesia in the obese patient

Abstract

We would like to report a novel needle-through-Quincke needle technique for assisting the establishment of spinal anaesthesia in the obese patient that two of the authors have used as their standard for obese patients in obstetric and orthopaedic settings for several years. Difficulties in successfully establishing subarachnoid anaesthesia often occur with obese patients and these can be further compounded during pregnancy by additional weight gain, oedema and problems with optimal positioning. The use of ultrasound to localise the spinal anatomy, including location of the interspinous spaces and the depth of the epidural space, has been well documented [1, 2], as has the use of an epidural needle as an introducer for long spinal needles [3]. We use ultrasound to locate a suitable space and to measure the depth of the dura. We mark the space as a needle insertion point. We then insert a 9-cm 20-G Quincke spinal needle (Becton Dickinson, Franklin Lakes, NJ, USA) through the marked point to a depth some 2–3 cm short of the dura, as measured by ultrasound. We then pass a 12-cm 24-G Sprotte needle (Pajunk, Geisingen, Germany), through the ligamentum flavum and dura into the cerebrospinal fluid (CSF). Should CSF not be visible within the Sprotte needle, we advance both needles together until successful dural puncture occurs. Should ultrasound be unavailable or unhelpful in identifying the space, we employ a blind approach. We insert the Quincke needle into the interspinous ligaments and then pass the long Sprotte needle through the Quincke needle, to project beyond the end of the latter. We can then advance the two needles together, with the atraumatic tip of the Sprotte needle acting as the leading point. We believe our technique avoids some of the potential problems of using a Tuohy needle as a spinal introducer, in particular, the inability to pass the spinal needle through the Huber tip, the deflection of the spinal needle by the Huber tip, the ‘dry tap’ that can occur after successful localisation of the epidural space [4], and a significantly smaller breech to the dura should accidental puncture occur with the Quincke needle. Dural puncture is extremely unlikely, as the leading point is that of the Sprotte needle. The Quincke needle is sufficiently stiff to allow easy placement even in very obese patients. We believe that ultrasound localisation adds to the accuracy of the technique, by providing accurate anatomical information of depth and the required angle of needle insertion. No external funding and no competing interests declared.