Stylet Stuck in the Back: An Unusual Complication of Spinal Needle

Abstract

To the Editor: A 33-yr-old male patient was scheduled to undergo release of knee contracture under spinal anesthesia. A 23-gauge disposable Quincke bevel needle (Becton Dickinson, India Limited) was inserted in the L3-4 interspace with the patient in the sitting position. At a depth of about 4 cm, an increase in resistance was felt. Believing that the needle had entered the ligamentum flavum, a slight increase in force was made. The needle went in with a jerk for approximately 2 mm and then got stuck. An attempt to remove the needle met with unexpectedly high resistance. On the second attempt, the stylet hub came off its junction with the shaft. Hoping that the stylet might come along, the needle was pulled out. Although the needle was removed without difficulty, the stylet remained lodged inside. Increasing the flexion of spine and pulling gently were unsuccessful. It was eventually pulled out forcibly, during which the patient complained of pain. On removal, it was observed to be bent at a right angle approximately 2 mm from the tip (Fig. 1). The patient consented to repeat spinal anesthesia with a fresh needle, which was successful in the same interspace.Figure 1.: A, the needle tip showing bent stylet. B, needle and the broken off hub with stylet bent at the tip.The tip of a fresh needle was closely examined to determine the possible mechanism of this complication. It looked normal; however, a large circumferential space between the stylet and lumen of the needle was seen under the microscope. The authors believe that when the first resistance to the advancing needle was encountered, the tip of the stylet had contacted the edge of the bone. On increasing the force, the tip of the needle slipped off the edge while the tip of the stylet levered at the heel of the needle bevel and bent. Second, the possibility of a slight forward movement of the stylet tip beyond the needle bevel while the force was applied on the hub during insertion cannot be excluded. This may have allowed it to contact the edge of the bone earlier. Bending of stylet in a reusable needle as a result of interchange of the stylet and needle at the time of packing the spinal set has been reported (1). We wish to note that it can occur with single-use needles also. The report serves to highlight the need for inspection of the needle before insertion. Puneet Sharma, MD Department of Anesthesia and Critical Care Max Hospital Baljit Singh, MD Department of Anesthesiology and Intensive Care G.B. Pant Hospital [email protected] Amod Manocha, DA Department of Anesthesia and Critical Care Vardhman Mahavir Medical College and Safdarjung Hospital New Delhi, India