In January 2015, the Committee on Safety of the Japan Society of Pain Clinicians (JSPC) distributed a questionnaire on pain management-related adverse events (AEs) in 2014 to all 343 board-certificated training facilities in Japan. Responses were received from 173 facilities (50％). Similar to the results of the 2012 and 2013 surveys, most reported AEs were classified as side effects of analgesics or analgesic adjuvants, or as complications of nerve blocks or interventional therapy. Side effects of non-steroidal anti-inflammatory drugs, pregabalin, and tramadol/acetaminophen were most frequently reported. The complications of nerve blocks and interventional therapy were as follows: loss of consciousness or respiratory-circulatory failure induced by the intravascular injection of local anesthetics; pneumothorax after an intercostal nerve block or trigger point injection; infection or hematoma induced by a stellate ganglion or epidural nerve block. It is necessary to share information on these AEs among the members of the JSPC and enhance the consideration of risk management in pain treatment settings.

A 23-year-old man with recurrent thymus cancer was diagnosed with brain metastases and underwent surgical resection. Prior to the surgery, he had experienced pain due to invasive recurrent tumors in the left thoracic cavity. The pain was managed using 640 mg of oxycodone sustained-release tablets, 240 mg of morphine sustained-release tablets, and 320 mg of ketamine liquid, administered daily. These medications were continued until the morning of surgery; the operation was performed under general anesthesia. Post-operatively, he was initially administered 80 mg of short-acting oxycodone powder through the nasogastric tube at the onset of pain, while the regular analgesic medication was suspended. From 24-hours post-surgery onward, he received 200 mg of short-acting oxycodone and 80 mg of ketamine through the nasogastric tube at fixed intervals of 6 hours. His regular oral medications were resumed 48 hours after surgery. Our experience suggests that if the postoperative fasting period is short, optimal postoperative cancer pain management can be achieved by administering short-acting oxycodone powder and ketamine through a nasogastric tube.

A 64-year-old female patient presented with a 4-month history of exaggerated spasms in her right eye-lid. Her spasms had gradually spread to the oral angle. She was referred to our department after the effective carbamazepine therapy had to be discontinued owing to leucopenia. Besides right facial spasms, ipsilateral tenderness in the cervical paravertebral area was noted. She was diagnosed with hemifacial spasm and cervical facet pain. Oral clonazepam was administered, followed by cervical facet block treatment, which was effective in providing relief from both, the hemifacial spasm and the facet pain. This experience suggests that the alleviation of pain-related stress might indirectly improve hemifacial spasm.

Although back pain complaints are common among patients of pain clinics, there are also patients with a rare underlying disease. We present the case of a patient with synovitis-acne-pustulosis-hyperostosis-osteitis (SAPHO) syndrome who was admitted to our hospital because of upper back pain. SAPHO syndrome consists of various osteoarticular and dermatological manifestations that can concurrently appear in a single patient. In this case, the patient complained of chronic recurrent back pain for seven years prior to the appearance of a skin lesion. MR imaging at the first visit revealed abnormal signal intensities in the sixth and seventh thoracic vertebral bodies. However, it was difficult to make a diagnosis without recognition of this syndrome. It should be considered that vertebral pain can occur before skin lesion development in patients with SAPHO syndrome.

An 80-year-old man underwent a transverse colectomy under combined epidural and general anesthesia. On the first postoperative day (POD), he complained of reduced sensation in the right leg and motor weakness. On the second POD, his symptoms progressed to paraplegia and analgesia below Th6. An epidural hematoma was observed using magnetic resonance imaging (MRI) on the third POD. An emergent laminectomy was performed, but the neurological deficits did not improve. We developed a protocol for the early diagnosis and management of epidural hematomas following this case. Five years later, a man in his 70s underwent bypass surgery for duodenal stenosis under combined epidural and general anesthesia. On the fourth POD, he complained of back pain and subsequently had paraplegia and analgesia below Th6. An emergent MRI, performed in accordance with the protocol, revealed an epidural hematoma. The symptoms disappeared immediately after removal of the hematoma. We suggest that it is necessary to establish a protocol for the management of epidural hematomas.

The subdural injection of local anesthetic is a rare complication of epidural injections. A 75-year-old female patient presented with right side cervical pain radiating into the right upper extremity. She received a fluoroscopy-guided right T1 transforaminal epidural injection. When the contrast medium was injected, it showed the right side T1 dorsal root ganglion. After injection of a local anesthetic, the patient complained of numbness of the right upper extremity. Numbness and motor weakness gradually extended to both arms and both legs. After ten minutes, she experienced respiratory difficulty. Moderate hypotension and bradycardia occurred, but her mental state was unaffected. Her symptoms resolved within two hours. She was discharged from our hospital the next day without experiencing any adverse events, including an orthostatic headache. The subdural space is a narrow space between the dura mater and the arachnoid membrane. The injection of local anesthetics into this space induced widespread neural blockage. Interventional pain physicians must have adequate knowledge of normal and abnormal patterns of epidural contrast dispersion.