Ultrasound-Guided Taylor's Approach in Ankylosing Spondylitis.

Ankylosing spondylitis (AS) is a chronic inflammatory disease of the spine which leads to ossification and formation of a classical bamboo spine. This poses a challenge to the anesthetist both in terms of administering general and regional anesthesia due to the limited mobility of the spine. With the advent of ultrasound as an aid in regional anesthesia, it has been relatively easy to perform a central neuraxial blockade in such patients though the skill requires some degree of expertise. Here, we have described the use of ultrasound as a guide for administering regional anesthesia to a patient with AS after initially attempting a blind approach which had failed due to difficult anatomy.

INTRODUCTION

Ankylosing spondylitis (AS) is a chronic inflammatory disease of the axial skeleton and peripheral joints.[1] It usually begins between the second and the fourth decades of life, mainly affecting males (5:1) and human leukocyte antigen-B27-positive individuals.[2] AS has almost always been a challenge to the anesthesiologist due to either a difficult airway or technical difficulties encountered while performing a central neuraxial blockade. Due to ossification of interspinous ligaments and enthesitis; there is the formation of a bamboo spine-like appearance which includes syndesmophyte formation, squaring of the vertebral bodies, vertebral endplate destruction, and Achilles tendinitis. This makes it difficult to place epidural or spinal needle when the disease involves the lumbar spine.

The cervical spine may be involved which makes the movement of neck difficult. The involvement of temporomandibular joints may progress to complete ankylosis of the joint. All of this along with the involvement of cricoarytenoid joints makes tracheal intubation more difficult and labels the patient as a case of difficult airway.[3] Recently, with the advent of ultrasound, the role of ultrasound-guided central and peripheral nerve blocks has helped in achieving predictable success.[4] Where the conventional central neuraxial blockade fails, a modified paramedian approach, also known as the Taylor's approach is helpful in such cases.[5]

Ultrasound helps in identifying the anatomic landmarks before regional anesthesia and makes it easier to perform the blockade with minimal number of attempts. It also puts the patient at ease and saves him/her from multiple attempts/needle puncture. In this case, we initially tried to administer regional anesthesia (spinal anesthesia) to the patient by the conventional blind technique. However, we were unsuccessful in attempting to do so. Hence, we decided to use the ultrasound as an aid in guiding us for performing the block. We were able to establish the landmarks with the help of ultrasound which we were having a difficulty with in the blind technique. Once the landmarks were established, the block could be performed easily.

CASE REPORT

A 60-year-old male, known case of severe AS, symptomatic since 2010, was posted for right total hip replacement (THR). He had a classical bamboo spine with no mobility of cervical or thoracolumbar spine [Figures 1 and 2]. The patient previously had neck pain for which he took treatment at various places since 2010. At present, his neck is totally stiff with no neck movement possible in any direction. He was not able to lie down straight and could do so only in a lateral position with the help of pillows. For 6 months, the patient had been walking with the help of a stick and was not able to bend his right knee. He had a history of pulmonary tuberculosis 20 years back for which he completed full treatment. He is a known case of gastroesophageal reflux disease for which he is taking treatment. The patient was also a reformed smoker. There was no history of any other comorbidity present. The cardiac and respiratory systems were normal on examination, and his hematological and biochemical parameters were also within normal limits. After thorough preanesthetic evaluation, he was posted for THR. A consent was also taken for fiberoptic intubation in case regional anesthesia could not be established. The patient was shifted to the operation theater. An intravenous access was established. Monitors were attached including pulse oximetry (SpO2), noninvasive blood pressure monitoring, and electrocardiogram. Baseline vitals were recorded. The primary plan was to go for a central neuraxial blockade (spinal anesthesia). The patient was then placed in sitting position. Under sterile aseptic precautions, back was painted and draped. Initially, lumbar puncture was attempted at L3-L4 intervertebral space by median and paramedian approach which failed. A second attempt was made at L4-L5 intervertebral space by paramedian approach which also failed. It was then decided to use the ultrasound for identifying the landmarks before spinal anesthesia. Taylor's approach was planned this time as this technique has been proved useful in many studies specifically for patients with AS.[56] With the patient in sitting position, a 2–7 MHz curvilinear ultrasound probe was placed in the paramedian position at L5-S1 intervertebral space. Transverse process of L5 vertebrae was identified and marked on the skin. The probe was then tilted slightly oblique from this position, and the L5-S1 interspace was identified. This space was marked on the patient using a skin marker pen [Figures 3 and 4]. The probe was then placed in the transverse plane at the level of L5-S1 intervertebral space. Spinous process and lamina of L5 vertebra were identified [Figures 5 and 6]. Anterior and posterior complex could also be faintly identified at this level. The midpoint of the probe was identified as the L5-S1 intervertebral space. After markings, the back was again cleaned of all the ultrasound gel and was cleaned and draped under sterile aseptic precautions. A 23-Gauge Quincke needle was placed in paramedian position at the point marked identified as L5-S1 intervertebral space. The needle was angulated at 30° and directed toward the midline. A loss of resistance was felt as needle was advanced further. Stylet was withdrawn, and free flow of cerebrospinal fluid (CSF) was noted. After ensuring free flow of CSF and ensuring negative aspiration for blood, 2.8 ml of injection bupivacaine and 25 μg of injection fentanyl was given. The patient was made to lie in supine position. After 8 min, the level of anesthesia was fixed at T8 level. The surgery was started and took around 3 h for completion. The patient remained stable throughout the procedure. There was no incidence of hypotension intraoperatively. Postsurgery, the patient was shifted to the postanesthesia care unit where the patient remained for around 4 h before being shifted to the ward. He finally heaved a sigh of relief after successful completion of the surgery [Figure 7].

Figure 1

Cervical spine images as observed in X-ray of the neck (anteroposterior and lateral views)

Figure 2

X-ray of the thoracolumbar spine showing a classic “bamboo” appearance

Figure 3

The transducer placed in parasagittal plane at L5-S1 interspace

Figure 4

The marking shows the L5-S1 interspace

Figure 5

The transducer probe in transverse plane in midline

Figure 6

Arrows showing spinous process and laminae of vertebrae

Figure 7

The smiling patient postsurgery

DISCUSSION

AS is a chronic inflammatory disease of the axial skeleton. The inflammatory process starts from sacroiliac joints and spreads cephalad to affect the spine up to the cervical level along with costovertebral joints. This can cause stiffness of the axial skeleton with ossification of axial ligaments and sacroiliac joints leading to decreased intervertebral spaces causing spinal rigidity.[7] The formation of bony bridges (syndesmophytes) between vertebrae results in a classic “bamboo spine” appearance. Regional anesthesia may offer certain benefits over general anesthesia in such patients, but more than often technical difficulties are encountered while doing so because of the pathological process itself. Schelew and Vaghadia planned spinal anesthesia in only 16 patients out of which they reported success in 10.[8] A paramedian approach may be easier because of the midline ossification of the interspinous ligaments. Taylor's approach, a paramedian approach to L5-S1 interspace, is a good alternative to conventional midline spinal anesthesia in such cases.[5] Ultrasound may also be a useful preoperative assessment tool for assessing the feasibility of central neuraxial blockade when the technical difficulty is anticipated.[91011] Chin and Chan demonstrated the accurate location of L5–S1 intervertebral space with ultrasound when several attempts on lumbar puncture had failed in the same patient.[9]

CONCLUSION

The ultrasound-guided paramedian approach could possibly serve as an alternative blockade in patients with advanced AS where the conventional method fails.[12] A recent study has been conducted which shows a preprocedural ultrasound which has been used to guide central neuraxial blockade in AS.[6] However, there is the scope of more studies in this regard in the future.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.