A 72-year-old woman (40.3 kg, 139 cm) was referred to our pain clinic for the treatment of low back pain after two back surgeries. She had first undergone back surgery [posterior lumbar interbody fusion (PLIF at L4–5) plus spinal stabilization (L3)] for lumbar spinal canal stenosis 4 years prior to the current presentation. Two weeks after the initial surgery, she underwent reoperation because of screw placement errors, and her symptoms disappeared after surgery. However, her low back pain recurred after a fall 5 months before the current presentation. Paralysis of the lower limbs was not apparent after this episode. A sensory disturbance that had existed before the surgeries remained unchanged. No new lesions such as a lateral recess or foraminal stenosis, herniated nucleus pulposus, or fracture were found on radiographs or magnetic resonance images (Fig. ). The previous medical institution prescribed acetaminophen and tramadol for low back pain and performed a caudal epidural block with 5 ml of 1% lidocaine and dexamethasone 1.65 mg. However, neither treatment provided pain relief, and the patient was referred to our pain clinic. She had several comorbidities, including diabetes mellitus, hypertension, renal dysfunction, hypothyroidism, rheumatic arthritis, and gastroesophageal regurgitation, and was prescribed 27 different drugs by clinicians from five different facilities. Accordingly, we decided not to use additional medication for first-line therapy because of polypharmacy concerns and renal dysfunction and performed bilateral ESP block with the patient in the prone position. A convex type transducer was placed in a longitudinal orientation at the level of the L2 transverse process, 3 cm lateral to the midline. The L4 and L5 transverse processes could not be identified because of the echogenic artifacts due to the surgical instruments. The posterior surface of the L2 transverse process was identified using an aseptic technique. After the puncture point was anesthetized with 2 ml of 1% lidocaine, the needle was inserted in the plane of the ultrasound beam in a cephalad to caudal direction. Following confirmation of the needle tip on the surface of the transverse process of L2, 20 ml of 0.1875% ropivacaine (fourfold dilution of commercial product) was injected into the target plane between the erector spinae muscles and the transverse process (Fig. ). This procedure was repeated on the contralateral side. Twenty-five minutes later, the patient reported a warm feeling in her low back and almost complete relief from pain, which was approximately < 10% of its original severity. There was an area of diminished cold sensation extending from T12 to L5, with no change in the anterior and lateral abdomen. Unfortunately, the pinprick test was not performed. Pain relief lasted for approximately 10 h after the initial block. We repeated this procedure for a total of three times in a month. Finally, the patient reported that her daily baseline level of low back pain had diminished to < 40% of its original severity. She was satisfied with the extent of pain control and did not wish to undergo further treatments such as epiduroscopy or spinal cord stimulation (SCS).
An 86-year-old female patient weighing 82 kg with 1-week-old right femoral neck fracture was scheduled for internal fixation or hemiarthroplasty. Medical history was significant for hearing loss, cerebrovascular event 7 years ago and severe aortic stenosis. Physical examination and laboratory tests were positive for Grade IV murmur on the aortic area and high serum creatinine (2.33 mg/dl). Peripheral arterial blood gases without O2 support were as follows: pH: 7.40, PaCO2: 38.3 mmHg PaO2: 66.7 mmHg and O2 saturation: 90%. Posterior-anterior chest X-ray showed right hilar widening, elevated left hemidiaphragm and an area of atelectasis/mass in the left basal segment. Initial electrocardiogram (ECG) revealed atrial fibrillation-flutter and a follow-up ECG demonstrated sinus rhythm. Patient was classified as being American Society of Anesthesiology Class 4. The patient and family were informed of the high risk of morbidity and mortality and written informed consent was obtained. After considering all comorbidities, general or spinal/epidural anaesthesia was considered to be of considerable risk. Therefore, a combination of peripheral nerve blocks was considered as alternatives. Premedication of 1 mg midazolam was performed. Invasive arterial pressure monitoring added to standard monitorisation plan.\nPatient was placed in the left lateral decubitus position. After aseptic precautions and skin preparation, the fourth lumbar vertebral spinous process was identified, and a low-frequency convex transducer was placed 4 cm lateral to the midline on the parasagittal plane. The transverse process and erector spinae muscles were visualised. A 10 cm 22G needle was advanced using the out-of-plane technique. After contact with the transverse process, local anaesthetic (0.5% bupivacaine 20 ml, 2% lidocaine 8 ml and 12 ml isotonic saline) was administered. Thereafter, the transducer was placed in the transverse plane on the flank of the patient cranial to the iliac crest. The fourth lumbar vertebral transverse process, erector spinae psoas and quadratus lumborum muscles were identified. A 15 cm 22G needle was inserted on the posterior corner of the convex probe. Twenty millilitres of local anaesthetic (0.5% bupivacaine 10 ml, 2% lidocaine 4 ml and 6 ml isotonic NaCl) was administered between the quadratus lumborum and psoas muscles. This ratio of LA was chosen considering toxic levels of each component and is customised for this patient.\nFollowing blocks, the patient was placed in the supine position. After 20 min, pinprick test revealed sensory block between T10 and L4 dermatomes. The patient was able to move her feet; however, there was no movement of the hip joint. The patient had no pain. There was no sensorial or motor block on the contralateral side, possibly excluding the presence of epidural spread. Surgery commenced at 35th min following nerve block. Partial hip prosthesis was performed in 2 h. Twenty-five micrograms of fentanyl was administered once for arterial line placement and once because of the slight increase in blood pressure, making the total administered dose 50 mcg. Interventions involving the medial aspect of the femur, innervated by the obturator nerve, led to mild pain and increments of 10 mg of intravenous ketamine was given totalling 40 mg. Post-operative analgesia plan included paracetamol that was administered every 8 h. Examination at postoperative 12th h revealed no pain at rest or on movement. Numeric Rating Scale was ≤2/10 for the first 16 post-operative hours during which time rescue analgesia was not required.