Background: The development of back pain following epidural analgesia is one reason for patient refusal of neuraxial analgesia. The primary endpoint of this study was to compare the incidence and severity of back pain following midline and paramedian epidural technique. The secondary endpoint was to identify the risk factors associated with the occurrence of back pain.Methods: This prospective randomized study included 114 patients receiving thoracic epidural catheterization for pain management following upper abdominal or thoracic surgery. Patients were allocated to either the midline or the paramedian group by computer-generated randomization. An investigator who was blinded to the patient group interviewed patients at 24, and 48 h, and 3–5 days after surgery about the existence of back pain and its severity.Results: The total incidence of back pain following epidural anesthesia was 23.8% in the midline group and 7.8% in the paramedian group. The numerical rating scale of back pain was not different between the two groups at 24 h and 4 days after surgery. The paramdian technique was associated with a lower incidence of back pain than the midline technique (95% confidence interval 0.05–0.74, odds ratio 0.2, P < 0.01). However, the number of attempts, surgical position, body mass index, and duration of surgery were not associated with back pain.Conclusions: This study showed that the midline group of thoracic epidural analgesia demonstrated higher incidence of back pain than the paramedian group. However, the pain was mild in intensity and decreased with time in both groups.

Hong JH, et al. Korean J Pain. 2016 Oct;29(4):255-261. https://doi.org/10.3344/kjp.2016.29.4.255

Background: The high thoracic erector spinae plane block (ESPB) has been used for the management of chronic shoulder pain or arthroscopic shoulder surgery. No study has evaluated the analgesic efficacy of ESPB in patients with cervical radiculopathy although it is a favored and easy technique compared to neuraxial block. The purpose of this study was to compare the treatment outcome of cervical radiculopathy using high thoracic ESPB or cervical interlaminar epidural injection (CEPI).Methods: This study included 82 patients with neck and arm pain who received CEPI (CEPI group) using 4 ml of 0.1% ropivacaine or high thoracic ipsilateral ESPB (ESPB group) at the T2 or T3 level using 20 ml of 0.1% ropivacaine 20 ml. The degree of pain relief and disability were assessed using an 11-point numerical scale (NRS) and neck disability index (NDI), respectively.Results: The CEPI and ESPB groups demonstrated an equal number of patients with excellent pain relief (NRS reduction > 50%). Significant reduction of NRS was found in both groups, and the effect of time was statistically significant in the groups (P < 0.001). The number of patients who showed an excellent improvement in NDI (NDI reduction > 30%) was 20 (48.8%) and 22 (53.7%) in the CEPI and ESPB groups, respectively.Conclusions: Both the CEPI and ESPB demonstrated significant relief in neck and arm pain with improvement in disability.

BackgroundSpontaneous intracranial hypotension occurs due to cerebrospinal fluid leakage from the spinal column, and orthostatic headache is the most common clinical presentation. Recent studies showed that bilateral greater occipital nerve blockade demonstrated clinical efficacy in relieving post-dural puncture headache after caesarean section. CaseA 40-year-old male who presented severe orthostatic headache was consulted to our pain clinic from neurology department. He initially felt a dull nature pain over the whole occipital area which then spread over the frontal and parietal areas. His headache was combined with nausea and vomiting. An epidural blood patch was delayed until final cisternography, and bilateral greater occipital nerve blockade using ultrasound guidance was performed instead. After the blockade, the previously existing headache around the occipital and parietal areas disappeared completely, but mild headache persisted around the frontal area.ConclusionsGreater occipital nerve blockade could be a good therapeutic alternative to improve headache resulting from spontaneous intracranial hypotension.

The identification of epidural space with loss of resistance (LOR) is commonly performed. But it lacks specificity. Epidural pressure waveform analysis (EPWA) provides a simple confirmative adjunct for LOR. If the needle is located within the epidural space, measurement of the pressure at its tips shows a pulsatile waveform. Previous studies demonstrated satisfactory sensitivity and specificity of EPWA. However, success or failure of epidural injection was confirmed by the pinprick test, which is limited for patients in the setting of the pain clinic. In this study, we evaluated the sensitivity, specificity, as well as positive and negative predictive values of EPWA for cervical epidural steroid injection (CESI) confirmed by fluoroscopy. One hundred and five CESIs of 75 patients suffering from neck and radicular arm pain of over 3 months duration were enrolled. The physician injected 5 mL of normal saline after a feeling of satisfactory LOR. Saline filled extension tubing, connected to a pressure transducer, was attached to the needle. A 3 mL bolus of contrast medium was injected to confirm the success of CESI. The incorrect identification of epidural space with LOR (false LOR) was 29.5%. Of these 31 failed CESIs, 2 showed epidural waveform and 29 did not. The sensitivity, specificity, positive and negative predictive value of EPWA was 94.5%, 93.5%, 97.2%, and 87.7%, respectively. EPWA shows satisfactory reliability and is a simple adjunct to decrease false LOR for CESI. Further confirmative studies are required before its routine use in clinical practice.

Background: Robot-assisted laparoscopic radical prostatectomy is an advanced and popular surgical technique. However, increased intracranial pressure which is caused by CO2 pneumoperitoneum and Trendelenburg position is the main cerebrovascular effect. Measurement of optic nerve sheath diameter using ocular ultrasound is a noninvasive and reliable method for the assessment of intracranial pressure. The primary endpoint of this study was to identify whether low blood pressure regulation has any benefit in attenuating an increase of optic nerve sheath diameter during robot-assisted laparoscopic radical prostatectomy.Methods: Optic nerve sheath diameter and cerebral oxygen saturation were measured at baseline (supine position), one and two hours after pneumoperitoneum and Trendelenburg position respectively, and after return to supine position in normal (n = 27) and low blood pressure groups (n = 24).Results: Mean optic nerve sheath diameter values measured at one and two hours after pneumoperitoneum and Trendelenburg position were significantly increased compared to the baseline value (P < 0.001 in normal blood pressure group; P = 0.003 in low blood pressure group). However, the mean optic nerve sheath diameter and cerebral oxygen saturation measured at any of the time points as well as degrees of change between the two groups did not show any significant changes. The peak values of optic nerve sheath diameter in normal and low blood pressure groups demonstrated 14.9% and 9.2% increases, respectively.Conclusions: Low blood pressure group demonstrated an effect in maintaining an increase of optic nerve sheath diameter less than 10% during CO2 pneumoperitoneum and Trendelenburg position.