Jae Gyok Song

Minimum effective volume of mepivacaine for ultrasound-guided supraclavicular block.

Background The aim of this study was to estimate the minimum effective volume (MEV) of 1.5% mepivacaine for ultrasound-guided supraclavicular block by placing the needle near the lower trunk of brachial plexus and multiple injections. Methods Thirty patients undergoing forearm and hand surgery received ultrasound-guided supraclavicular block with 1.5% mepivacaine. The initial volume of local anesthetic injected was 24 ml, and local anesthetic volume for the next patient was determined by the response of the previous patient. The next patient received a 3 ml higher volume in the case of the failure of the previous case. If the previous block was successful, the next volume was 3 ml lower. MEV was estimated by the Dixon and Massey up and down method. MEV in 95, 90, and 50% of patients (MEV95, MEV90, and MEV50) were calculated using probit transformation and logistic regression. Results MEV95 of 1.5% mepivacaine was 17 ml (95% confidence interval [CI], 13-42 ml), MEV90 was 15 ml (95% CI, 12-34 ml), and MEV50 was 9 ml (95% CI, 4-12 ml). Twelve patients had a failed block. Three patients received general anesthesia. Nine patients could undergo surgery with sedation only. Only one patient showed hemi-diaphragmatic paresis. Conclusions MEV95 was 17 ml, MEV90 was 15 ml, and MEV50 was 9 ml. However, needle location near the lower trunk of brachial plexus and multiple injections should be performed.

Comparison of ultrasound-guided supraclavicular block according to the various volumes of local anesthetic

Background The ultrasound guidance in regional nerve blocks has recently been introduced and gaining popularity. Ultrasound-guided supraclavicular block has many advantages including the higher success rate, faster onset time, and fewer complications. The aim of this study was to examine the clinical data according to the varied volume of local anesthetics in the ultrasound-guided supraclavicular block. Methods One hundred twenty patients were randomized into four groups, according to the local anesthetic volume used: Group 35 (n = 30), Group 30 (n = 30), Group 25 (n = 30), and Group 20 (n = 30). Supraclavicular blocks were performed with 1% mepivacaine 35 ml, 30 ml, 25 ml, and 20 ml, respectively. The success rate, onset time, and complications were checked and evaluated. Results The success rate (66.7%) was lower in Group 20 than that of Group 35 (96.7%) (P < 0.05). The average onset times of Group 35, Group 30, Group 25, and Group 20 were 14.3 ± 6.9 min, 13.6 ± 4.5 min, 16.7 ± 4.6 min, and 16.5 ± 3.7 min, respectively. There were no significant differences. Horners syndrome was higher in Group 35 (P < 0.05). Conclusions In conclusion, we achieved 90% success rate with 30 ml of 1% mepivacaine. Therefore, we suggest 30 ml of local anesthetic volume for ultrasound-guided supraclavicular block.

Dyspnea after supraclavicular brachial plexus block in a morbidly obese patient due to phrenic nerve block - A case report -

A 57-year-old woman with morbid obesity (BMI: 37.39) was scheduled for ligament reconstruction with tendon interposition of the carpometacarpal joint. A difficult supraclavicular brachial plexus block was performed using a 22-gauge regional block needle with a nerve stimulator and 40 ml of 1% mepivacaine. Approximately 10 minutes after the injection, she complained dyspnea, shortness of breath and right mid-thoracic pain. Her oxygen saturation decreased from 100% to 95%. Diagnostic workup revealed right diaphragmatic elevation caused by phrenic nerve block. General anesthesia was induced because of the unsuccessful brachial plexus block and dyspnea with chest pain. She recovered without any residual complications and was discharged on the third postoperative day. Phrenic nerve block is a common complication in supraclavicular brachial plexus block but it is usually not severe and reassurance is enough to control it. However, pre-operative physical conditions that may lead to decreased respiratory reserves, such as morbid obesity should be considered as a risk factors when conducting supraclavicular brachial plexus block.

Epidural hematoma after thoracic epidural analgesia in a patient treated with ketorolac, mefenamic acid, and naftazone -a case report-

A 26-year-old male undergoing thoracotomy and bleeding control received a preoperative thoracic epidural for postoperative analgesia. On the fifth postoperative day, paralysis of both lower limbs occurred and urgent magnetic resonance imaging showed massive anterior epidural hematoma. During laminectomy and decompression, platelet dysfunction was diagnosed and preoperative non-steroidal anti-inflammatory drugs medications were supposed to the cause of platelet dysfunction. After infusion of ten units of platelet concentrate, coagulopathy was improved. We should be more careful to drugs with antiplatelet effect when using regional analgesia.

Intracerebral hemorrhage in a patient with preeclampsia and HELLP syndrome which was diagnosed after caesarean section - A case report -

Intracerebral hemorrhage (ICH) is one of very dangerous complications of preeclampsia/eclampsia. We experienced postoperative ICH in a 39-year-old woman with preeclampsia and HELLP syndrome. The paturient complained severe headache and upper abdominal pain with nausea and vomiting. Her initial blood pressure was 190/120 mmHg and her heart rate was 80 beat/min. The diagnosis of preeclampsia with HELLP syndrome was confirmed by the severe hypertension and the laboratory findings. She was drowsy at the emergency room but she lost consciousness when transferring to the operation room. Caesarean section was done under general anesthesia. After the operation she could not recover self-respiration and consciousness. Her brain CT showed ICH in the basal ganglia with intraventricular hemorrhage and severe brain edema. She expired one the 5 th post operative day due to brain death and multiple organ failure. Early diagnosis is the key to treating ICH.

Tuberculosis like lesion on the epiglottis of a patient with an extrapulmonary tuberculosis abscess - A case report -

Epiglottic tuberculosis without pulmonary involvement is an uncommon disease that has rarely been described in Korea. We report here a case of a 36 year-old man with a recurrent tuberculosis abscess in his thigh. He had been treated with steroids for systemic lupus erythematosus, and he suffered from recurrent tuberculosis abscess in the thigh where he had received total hip replacement arthroplasty. When inducing general anesthesia for incision and drainage, we noticed a destroyed epiglottis. After consultation with an otolaryngologist, we concluded that the patient has had epiglottic tuberculosis and precautions against tuberculosis infection were taken. The surgery ended without event. The patient recovered safely and was transferred from the operating room directly to the general ward. In this paper, we also discussed the epiglottic tuberculosis and precautions that were taken to prevent tuberculosis infection of the healthcare workers in the operating theater.

The correlation between the effects of propofol on the auditory brainstem response and the postsynaptic currents of the auditory circuit in brainstem slices in the rat

BACKGROUND Although there have been reports showing the changes of the auditory brainstem response (ABR) waves by propofol, no detailed studies have been done at the level of brainstem auditory circuit. So, we studied the effects of propofol on the postsynaptic currents of the medial nucleus of the trapezoid body (MNTB)-lateral superior olive (LSO) synapses by using the whole cell voltage clamp technique and we compared this data with that obtained by the ABR. METHODS 5 rats at postnatal (P) 15 days were used for the study of the ABR. After inducing deep anesthesia using xylazine 6 mg/kg and ketamine 25 mg/kg, the ABRs were recorded before and after intraperitoneal propofol injection (10 mg/kg) and the effects of propofol on the latencies of the I, III, and V waves and the I-III and III-V interwave intervals were evaluated. Rats that were aged under P11 were used in the voltage clamp experiments. After making brainstem slices, the postsynaptic currents (PSCs) elicited by MNTB stimulation were recorded at the LSO, and the changes of the PSCs by the bath application of propofol (100 microM) were monitored. RESULTS We found small, but statistically significant increases in the latencies of ABR waves III and V and the interwave intervals of I-III and III-V by propofol. However, no significant changes were observed in the glycinergic or glutamatergic PSCs of the MNTB-LSO synpases by the application of propofol (100 microM). CONCLUSIONS Glycinergic or glutamatergic transmission of the MNTB-LSO synapses might not contribute to the propofol-induced changes of the ABR.