Depth of double-lumen endobronchial tube: a comparison between real practice and clinical recommendations using height-based formulae

The depth of double-lumen endobronchial tube (DLT) is reportedly known tobe directly proportional to height and several height-based recommendations have beensuggested. This retrospective study was designed to find out the difference between calculated depths using height-based formulae and realistic depths in clinical practice of DLTplacement by analyzing pooled data from patients intubated with left-sided DLT.Methods: The electronic medical records of adults, intubated with DLT from February 2018to December 2020, were reviewed. Data retrieved included age, sex, height, weight, andsize and depth of DLT. The finally documented DLT depth (depth final, DF) was comparedwith the calculated depths, and the relationship between height and DF was also evaluated.A questionnaire on endobronchial intubation method was sent to anesthesiologists.Results: A total of 503 out of 575 electronic records of consecutive patients were analyzed.Although the relationship between height and DF was shown to have significant correlation(Spearman’s rho = 0.63, P < 0.001), DF was shown to be significantly greater than calculated depths (P < 0.001). Despite 57.1% of anesthesiologists have knowledge of clinical recommendations to anticipate size and depth of DLT, no one routinely utilizes those recommendations.Conclusions: Anesthesiologists tend to place DLTs in a deeper position than expected whendepths are calculated using height-based recommendations. Although such discrepanciesmay not be clinically meaningful, efforts are needed to standardize the methods of endobronchial intubation to prevent potential complications associated with malposition.

Intravenous Versus Perineural Dexamethasone for Reducing Rebound Pain After Interscalene Brachial Plexus Block: A Randomized Controlled Trial

Background@#Interscalene brachial plexus block (ISB) is a common regional technique to manage acute postoperative pain for arthroscopic rotator cuff tear repair. However, rebound pain may compromise its overall benefit. Our aim was to investigate the primary hypothesis that perineural and intravenous dexamethasone have different effects on rebound pain after resolution of ISB for arthroscopic rotator cuff tear repair. @*Methods@#Patients aged ≥ 20 years scheduled for elective arthroscopic rotator cuff tear repair under general anesthesia with preoperative ISB were included. The participants were randomized to receive dexamethasone either perineurally (perineural group) or intravenously (intravenous group). In the perineural group, patients received ISB with 12 mL of 0.5% ropivacaine containing 5 mg of dexamethasone; simultaneously, 1 mL of 0.9% normal saline was administered intravenously. In the intravenous group, patients received ISB with 12 mL of 0.5% ropivacaine; simultaneously, 1 mL of dexamethasone 5 mg was administered intravenously. The primary outcome was the difference in the pain score (0–10 on numeric rating scale) between before and after ISB resolution. The secondary outcomes were the incidence of rebound pain; onset, duration, and intensity of rebound pain; time to the first analgesic request; and pain-related sleep disturbance. @*Results@#A total of 71 patients were randomized to either perineural group (n = 36) or intravenous group (n = 35). After block resolution, pain scores increased significantly more in the perineural group (mean ± standard deviation, 4.9 ± 2.1) compared to the intravenous group (4.0 ± 1.7, P = 0.043). The duration of ISB was more prolonged in the perineural group (median [interquartile range], 19.9 [17.2–23.1] hours) than the intravenous group (15.1 [13.7–15.9] hours, P < 0.001). The incidence of rebound pain and pain-related sleep disturbance during the first postoperative week was significantly higher in the perineural group than in the intravenous group (rebound pain: 44.4% vs. 20.0%, P = 0.028; sleep disturbance: 55.6% vs. 25.7%, P = 0.011). The duration and intensity of rebound pain were similar between the two groups. @*Conclusion@#Although perineural dexamethasone provided longer postoperative analgesia, intravenous dexamethasone was more beneficial in reducing pain increase after ISB resolution, incidence of rebound pain, and pain-related sleep disturbance.

Association between anesthetic method and postpartum hemorrhage in Korea based on National Health Insurance Service data

Postpartum hemorrhage (PPH) is a major cause of maternal mortality and the risk factors for PPH differ among studies. In this large-scale study, we investigated whether the anesthetic method used was associated with PPH after cesarean section. Methods: We extracted data on cesarean sections performed between January 2008 and June 2013 from the National Health Insurance Service database. The anesthetic methods were categorized into general, spinal and epidural anesthesia. To compare the likelihood of PPH among deliveries using different anesthetic methods, crude and adjusted odds ratios (ORs) and 95% confidence intervals were calculated using logistic regression analysis. Results: Data from 330,324 cesarean sections were analyzed, and 21,636 cases of PPH were identified. Univariate analysis showed that general and epidural anesthesia increased the risk of PPH compared to spinal anesthesia. The OR for PPH was highest for morbidly adherent placenta, followed by placenta previa, placental abruption, and hypertension. When other clinical covariates were controlled for, general and epidural anesthesia still remained significant risk factors for PPH compared to spinal anesthesia. Conclusions: This study showed that general and epidural anesthesia elevated the risk of PPH compared to spinal anesthesia during cesarean section. Since we could not consider the potential bias of group differences in indications, more in-depth clinical trials are needed to validate our findings. Obstetric factors such as placental abnormalities had high odds ratios and thus are more important than the choice of anesthetic method, which should be based on the patient’s clinical condition and institutional resources.

Effects of Intraoperative Ventilation Strategy on Perioperative Atelectasis Assessed by Lung Ultrasonography in Patients Undergoing Open Abdominal Surgery: a Prospective Randomized Controlled Study

Background@#Protective mechanical ventilation using low tidal volume has been introduced to surgical patients to reduce the incidence of postoperative pulmonary complications. We investigated the effects of protective ventilation (PV) techniques on anesthesia-induced atelectasis identified via lung ultrasonography in patients undergoing abdominal surgery. @*Methods@#A total of 42 adult patients who were scheduled for open abdominal surgery with an expected duration > 2 hours were included in the study. Patients were randomized to receive either conventional ventilation (CV; tidal volume of 9–10 mL/kg predicted body weight [PBW] with no positive end-expiratory pressure [PEEP]) or PV (tidal volume of 6–8 mL/kg PBW and 5 cmH 2 O PEEP) via pressure-controlled ventilation with volume guaranteed.Lung ultrasonography was performed at four predefined time points to assess perioperative atelectasis by dividing each hemithorax into six quadrants based on a modified lung ultrasound (LUS) scoring system. @*Results@#The tidal volume delivered to patients was 9.65 ± 1.65 mL/kg PBW in the CV group and 6.31 ± 0.62 mL/kg PBW in the PV group. Ventilation using low tidal volume led to similar LUS scores in all lung areas and at all time points compared to ventilation using high tidal volume. There was no significant difference between the groups in the number of patients requiring recruitment maneuvers at the end of surgery. @*Conclusion@#Ventilation with low tidal volume combined with 5 cmH2O PEEP did not cause further loss of aeration compared to ventilation with high tidal volume. Low tidal volume ventilation can be used in patients without lung injury based on lung assessment by bedside lung ultrasonography.

Endotracheal Intubation Using McGrath Videolaryngoscope in Klippel-Feil Syndrome / 이화의대지

Patients with Klippel-Feil syndrome require much attention during anesthesia because of congenital abnormalities in head and neck regions and the high probability of neurological damage from cervical spine instability during endotracheal intubation. We report a case of successful endotracheal intubation using a videolaryngoscope in a patient with Klippel-Feil syndrome who experienced difficult transnasal intubation.

Compression stockings reduce the incidence of hypotension but not that of cerebral desaturation events in the beach-chair position: a randomized controlled trial / 대한마취과학회지

BACKGROUND: The beach-chair position (BCP) results in decreases in venous return, cardiac output, and cerebral perfusion pressure. In this randomized, prospective study, we investigated whether applying thigh-high compression stockings affected the maintenance of regional cerebral tissue oxygen saturation (rSO2) in the BCP. METHODS: Patients undergoing orthopedic surgery in the BCP under general anesthesia were included and assigned randomly to the control or the compression stocking group. Appropriately sized thigh-high compression stockings were applied to the patients in the stockings group. All patients were tilted, up to 45°, throughout the operation. Non-invasive blood pressure, invasive arterial blood pressure zeroed at the external auditory meatus, and rSO2 were recorded. RESULTS: Data were analyzed from 19 patients per group. In the BCP, the values of rSO2 and blood pressure decreased significantly compared with those at baseline, with no significant difference between the groups. The incidences of cerebral desaturation events (CDEs) were similar between the groups; however, that of hypotension was significantly lower in the compression stocking group. During 36 CDEs, the levels of rSO2 and blood pressure decreased significantly compared with those at baseline in both groups. No significant correlation was found between rSO2 and blood pressure. CONCLUSIONS: Thigh-high compression stockings reduced the incidence of hypotension but not that of CDEs. Our results suggest that other factors, beyond hypotension itself, contribute to CDEs and in other words, efforts just to reduce the incidence of hypotension may not mainly contribute to a reduction of CDEs occurrence in the BCP under general anesthesia.

A retrospective analysis of neurological complications after ultrasound guided interscalene block for arthroscopic shoulder surgery

BACKGROUND: Ultrasound-guided interscalene brachial plexus block (US-ISB) has been reported to be effective postoperative analgesia for arthroscopic shoulder surgery. Although considered rare, various neurological complications have been reported. We retrospectively evaluated 668 patients for post operation neurological symptoms including hemidiaphragmatic paresis and post-operative neurologic symptoms after US-ISB. METHODS: We performed a retrospective chart review of 668 patients undergoing shoulder surgery with single-shot US-ISB from January 2010 to May 2015. The general anesthesia prior to the US-guided ISB procedure was standardized by expert anesthesiologists. Neurological postoperative complications were evaluated at 48 hours, about 2 weeks, 1 month, 3 months, 6 months, and up to resolution after operation. RESULTS: Three patients (0.4%) developed hemidiaphragmatic paresis (HDP), which were likely US-ISB associated and improved within 1 day. Two patients developed sensory symptoms, also likely US-ISB associated; one was paresthesia at the tip of the thumb/index finger, which resolved within 2 weeks, and the other was hypoesthesia involving the posterior auricular nerve, which resolved within 6 months. Motor and sensory symptoms which were not likely associated with US-ISB were hypoesthesia and pain (n = 28, 4.6%) and motor weakness (n = 2, 0.3%). CONCLUSIONS: Incidence of HDP and neurological complications, respectively 0.4% and 0.3%, related to transient minor sensory symptoms occurred after US-ISB for arthroscopic shoulder surgery but the complications improved spontaneously. Therefore, we confirm that the US-ISB procedure with low volumes of local anesthetics is an acceptable technique with a low rate of HDP and neurological complications.

Changes in Serum Concentrations of Insulin-like Growth Factor Binding Protein-3 after General Anesthesia Using Propofol or Isoflurane / 이화의대지

OBJECTIVES: The insulin-like growth factor binding proteins (IGFBP) regulate the bioavailability and bioactivity of insulin-like growth factor. We aimed to evaluate whether the IGFBP-3 level undergo major changes during perioperative periods according to the different kind of anesthetic agents. METHODS: Eighteen adults scheduled for elective total abdominal hysterectomy were enrolled. The patients were randomly assigned to have either propofol or isoflurane for maintenance of general anesthesia. A venous sample was taken for analysis of IGFBP-3 at the following time points: before induction, at the time of peritoneal closure, 1 hour after extubation at recovery room, and 2 and 5 postoperative days. The samples were analyzed by enzyme linked immunosolvent assay. RESULTS: Demographic data were similar between groups. In the both groups, the IGFBP-3 concentration decreased after anesthesia induction, reaching a nadir at the time of peritoneal closure without a significant difference between groups. In analysis between groups, the IGFBP-3 concentration in the isoflurane group on the postoperative 5th day was recovered to preoperative value and significantly higher than that in the propofol group (P < 0.05). CONCLUSION: This is the first study to show that the anesthetics used for general anesthesia affect the IGFBP-3 level during perioperative periods. The decrease of IGFBP-3 level following anesthesia induction in the isoflurane group was recovered to preoperative value, whereas that observed in the propofol group was not recovered on the postoperative 5th day. Further study is needed to establish the definitive effect of general anesthetics on IGFBP-3 and provide a comprehensive interpretation.

Influence of the Phase of Menstrual Cycle on Postoperative Nausea and Vomiting after Breast Cancer Surgery / 이화의대지

OBJECTIVES: The phase of the menstrual cycle was demonstrated to have an influence on the incidence of postoperative nausea and vomiting (PONV) after gynecologic laparoscopic surgery, but little was known for breast surgery, which was shown to have relatively higher incidence of PONV, >60%. We performed this study to investigate the influence of the phase of menstrual cycle on PONV after breast cancer surgery. METHODS: A total of 103 patients, who were scheduled for breast cancer surgery under general anesthesia, were recruited, and patients with irregular menstrual cycles, history of previous history of PONV were excluded. Groups were divided in two ways as follows: 1) gynecologic classification: premenstrual and menstrual (days 25 to 6), follicular (days 8 to 12), ovulation (days 13 to 15), and luteal phase (days 20 to 24); 2) menstrual classification: menstrual (days 1 to 8) and non-menstrual (days 9 to 28). PONV were recorded using Rhodes index of nausea, vomiting and retching at postoperative 6 and 24 hours. RESULTS: The overall incidence of PONV during postoperative 24 hours was 35.4%. At the menstrual classification, the incidence of PONV at postoperative 24 hours was higher in the menstrual group than that in the non-menstrual group (16.7% vs. 4.2%, P=0.057). The severity of PONV, measured with Rhodes index of nausea, vomiting and retching was significantly different between menstrual and non-menstrual groups (P=0.034). CONCLUSION: The duration and severity of the PONV after breast cancer surgery were demonstrated to be prolonged and aggravated during menstruation, respectively. Therefore, consideration of menstrual cycle for scheduling breast cancer surgery could effectively prevent the PONV and reduce medical cost.

Anesthetic Experiences of Liver Transplantation in a New Low Volume Hospital: Ewha Womans University Mokdong Hospital / 이화의대지

OBJECTIVES: Liver transplantation (LT) is the only treatment for end stage of liver failure. In Korea, annually it has been performed 1,300 cases. Most of LTs are performed in large volumes centers. More than half of centers performing LT in Korea are low volume hospital and started a LT program recently. We present our four-year experiences and outcomes of anesthesia for LT since 2013. METHODS: Anesthetic and surgical outcomes of 49 consecutive patients who received LT (living donor LT, 21 cases; deceased donor LT, 28 cases) between April 2013 and April 2017 were analyzed retrospectively. RESULTS: All patients were adult, with the mean age of 53.5±9.2 years. The most common cause of original liver diseases was hepatitis B virus-related liver cirrhosis (40.8%). The mean MELD (Model for End-stage Liver Disease) score was 18.8±10.7. Postreperfusion syndrome was observed in 34.7%, which were all controlled by calcium, norepinephrine, ephedrine and epinephrine. The mean postoperative intensive care unit stay of deceased donor LT recipients (13.6±9.0 days) was significantly longer than that of living donor LT recipients (8.0±3.3 days). There was no intraoperative mortality in patients receiving LT. Thirty-day post-transplant survival rate was 93.8% and 3-year survival rate was 88.6 %. The most common postoperative complication was pneumonia. CONCLUSION: We have started LT successfully with multidisciplinary team's steady effort. Adaptation and setting up LT protocol, adequate equipment, proper training at established transplant centers are essential to begin a successful LT program.

Hypoesthesia of the Cutaneous Branch of Cervical Plexus after Shoulder Arthroscopy under General Anesthesia with Ultrasound Guided-Interscalene Block / 이화의대지

We present an uncommon case of hypoesthesia in the posterior and upper third of the superior area on the left ear auricle, after arthroscopic surgery of the shoulder in the lateral position under general anesthesia with ultrasound guided-interscalene brachial plexus block. A 65-year-old man underwent arthroscopic rotator cuff repair of the left shoulder in the right lateral decubitus position. Two days after operation, he complained of numbness around the left auricle; his symptoms persisted until 6 weeks after surgery. Audiometry and sensory examinations were normal. He recovered naturally by 6 months postoperatively. Postoperative neurological deficits that may not be block-related can be attributed to a combination of factors, such as patient-, anesthesia-, and surgery-related factors, including direct trauma, positioning, and retraction. Anesthesiologists should be aware that the injury may not be block-related and consider other possible causes.

Comparison of Ultrasound-Guided Axillary Brachial Plexus Block Techniques: Perineural Injection versus Single or Double Perivascular Infiltration

PURPOSE: We compared three methods of ultrasound-guided axillary brachial plexus block, which were single, and double perivascular (PV) infiltration techniques, and a perineural (PN) injection technique. MATERIALS AND METHODS: 78 patients of American Society of Anesthesiologists physical status I-II undergoing surgery of the forearm, wrist, or hand were randomly allocated to three groups. 2% lidocaine with epinephrine 5 microg/mL was used. The PN group (n=26) received injections at the median, ulnar, and radial nerve with 8 mL for each nerve. The PV1 group (n=26) received a single injection of 24 mL at 12-o'clock position of the axillary artery. The PV2 group (n=26) received two injections of 12 mL each at 12-o'clock and 6-o'clock position. For all groups, musculocutaneous nerve was blocked separately. RESULTS: The PN group (391.2+/-171.6 sec) had the longest anesthetic procedure duration than PV1 (192.8+/-59.0 sec) and PV2 (211.4+/-58.6 sec). There were no differences in onset time. The average induction time was longer in PN group (673.4+/-149.6 sec) than PV1 (557.6+/-194.9 sec) and PV2 (561.5+/-129.8 sec). There were no differences in the success rate (89.7% vs. 86.2% vs. 89.7%). CONCLUSION: The PV injection technique consisting of a single injection in 12-o'clock position above the axillary artery in addition to a musculocutaneous nerve block is equally effective and less time consuming than the PN technique. Therefore, the PV technique is an alternative method that may be used in busy clinics or for difficult cases.

Effect of Propofol and Desflurane on Immune Cell Populations in Breast Cancer Patients: A Randomized Trial

Several factors can affect the perioperative immune function. We evaluated the effect of propofol and desflurane anesthesia on the surgery-induced immune perturbation in patients undergoing breast cancer surgery. The patients were randomly assigned to receive propofol (n = 20) or desflurane (n = 20) anesthesia. The total and differential white blood cell counts were determined with lymphocyte subpopulations before and 1 hr after anesthesia induction and at 24 hr postoperatively. Plasma concentrations of interleukin (IL)-2 and IL-4 were also measured. Both propofol and desflurane anesthesia preserved the IL-2/IL-4 and CD4+/CD8+ T cell ratio. Leukocytes were lower in the propofol group than in the desflurane group at 1 hr after induction (median [quartiles], 4.98 [3.87-6.31] vs. 5.84 [5.18-7.94] 10(3)/microL) and 24 hr postoperatively (6.92 [5.54-6.86] vs. 7.62 [6.22-9.21] 10(3)/microL). NK cells significantly decreased 1 hr after induction in the propofol group (0.41 [0.34-0.53] to 0.25 [0.21-0.33] 10(3)/microL), but not in the desflurane group (0.33 [0.29-0.48] to 0.38 [0.30-0.56] 10(3)/microL). Our findings indicate that both propofol and desflurane anesthesia for breast cancer surgery induce a favorable immune response in terms of preservation of IL-2/IL-4 and CD4+/CD8+ T cell ratio in the perioperative period. With respect to leukocytes and NK cells, desflurane anesthesia is associated with less adverse immune responses than propofol anesthesia during surgery for breast cancer. (Clinical trial registration at https://cris.nih.go.kr/cris number: KCT0000939)

Hydrothorax with alveolar-pleural fistula mimicking re-expansion pulmonary edema during liver transplantation: a case report / 대한마취과학회지

We present a case of an alveolar-pleural fistula with hepatic hydrothorax in a patient undergoing orthotropic liver transplantation, which was detected by drainage of transudate through an endotracheal tube during operation. A standard endotracheal tube was changed to a double-lumen tube to provide differential lung ventilation. The patient was diagnosed with an alveolar-pleural fistula by direct vision of an air leak during positive-pressure ventilation through a diaphragmatic incision. There was still a concern about worsening his ventilation due to persistent aspiration of pleural effusion towards the ipsilateral lung during the remaining operation period. Surgeon repaired the defect on the exposed lung surface via diaphragmatic opening. Anesthesiologists should consider an alveolar-pleural fistula as a possible differential diagnosis with re-expansion pulmonary edema when transudate emanating from the endotracheal tube is obtained in patients with massive hydrothorax.

The degree of labor pain at the time of epidural analgesia in nulliparous women influences the obstetric outcome / 대한마취과학회지

BACKGROUND: The increased pain at the latent phase can be associated with dysfunctional labor as well as increases in cesarean delivery frequency. We aimed to research the effect of the degree of pain at the time of epidural analgesia on the entire labor process including the mode of delivery. METHODS: We performed epidural analgesia to 102 nulliparous women on patients' request. We divided the group into three based on NRS (numeric rating scale) at the moment of epidural analgesia; mild pain, NRS 1-4; moderate pain, NRS 5-7; severe pain, NRS 8-10. The primary outcome was the mode of delivery (normal labor or cesarean delivery). RESULTS: There were significant differences in the mode of delivery among groups. Patients with severe labor pain had a significantly higher cesarean delivery compared to patients with moderate labor pain (P = 0.006). The duration of the first and second stage of labor, fetal heart rate, use of oxytocin and premature rupture of membranes had no differences in the three groups. CONCLUSIONS: Our research showed that the degree of pain at the time of epidural analgesia request might influence the rate of cesarean delivery. Further research would be necessary for clarifying the mechanism that the augmentation of pain affects the mode of delivery.

The Effects of a Forceful Transforaminal Epidural Steroid Injection on Radicular Pain: A Preliminary Study / 대한통증학회지

BACKGROUND: Lumbar transforaminal epidural steroid injections (TFESIs) are performed to provide symptom relief in patients with radicular pain. Recent articles suggested that injected volume itself have analgesic effects and higher volumes are associated with better outcomes. To date, few studies have been conducted to investigate the effects of volume. Therefore, well-designed controlled studies were necessary to confirm the effect of volume itself on pain relief. The purpose of this study was to examine the effectiveness of a forceful saline injection on lumbar TFESI using non-particulate steroids. METHODS: Fifty consecutive patients with lumbar radicular pain were enrolled. The participants were allocated into one of two groups: dexamethasone with volume (Group DV) and dexamethasone alone (Group DO). The volume was delivered by a forceful injection of 5ml of normal saline. The primary end-point for this study was a VAS pain score and modified MacNab score indicating the rate of effectiveness at the four-week follow-up. RESULTS: There were no significant post-procedural VAS differences between two groups (P = .252). The effectiveness rate among the patients was 47.8% in DV group, 34.8% in DO group, measured by modified MacNab score. The difference was not statistically significant (P = .117). CONCLUSIONS: A forceful saline injection did not have a significant effect during the treatment of radicular pain. Further studies with greater volumes and with additional techniques would offer a more conclusive perspective.

Does Intravenous Ketamine Enhance Analgesia after Arthroscopic Shoulder Surgery with Ultrasound Guided Single-Injection Interscalene Block?: A Randomized, Prospective, Double-Blind Trial

Ketamine has anti-inflammatory, analgesic and antihyperalgesic effect and prevents pain associated with wind-up. We investigated whether low doses of ketamine infusion during general anesthesia combined with single-shot interscalene nerve block (SSISB) would potentiate analgesic effect of SSISB. Forty adult patients scheduled for elective arthroscopic shoulder surgery were enrolled and randomized to either the control group or the ketamine group. All patients underwent SSISB and followed by general anesthesia. During an operation, intravenous ketamine was infused to the patients of ketamine group continuously. In control group, patients received normal saline in volumes equivalent to ketamine infusions. Pain score by numeric rating scale was similar between groups at 1, 6, 12, 24, 36, and 48 hr following surgery, which was maintained lower than 3 in both groups. The time to first analgesic request after admission on post-anesthesia care unit was also not significantly different between groups. Intraoperative low dose ketamine did not decrease acute postoperative pain after arthroscopic shoulder surgery with a preincisional ultrasound guided SSISB. The preventive analgesic effect of ketamine could be mitigated by SSISB, which remains one of the most effective methods of pain relief after arthroscopic shoulder surgery.

The Effects of a Forceful Transforaminal Epidural Steroid Injection on Radicular Pain: A Preliminary Study

BACKGROUND: Lumbar transforaminal epidural steroid injections (TFESIs) are performed to provide symptom relief in patients with radicular pain. Recent articles suggested that injected volume itself have analgesic effects and higher volumes are associated with better outcomes. To date, few studies have been conducted to investigate the effects of volume. Therefore, well-designed controlled studies were necessary to confirm the effect of volume itself on pain relief. The purpose of this study was to examine the effectiveness of a forceful saline injection on lumbar TFESI using non-particulate steroids. METHODS: Fifty consecutive patients with lumbar radicular pain were enrolled. The participants were allocated into one of two groups: dexamethasone with volume (Group DV) and dexamethasone alone (Group DO). The volume was delivered by a forceful injection of 5ml of normal saline. The primary end-point for this study was a VAS pain score and modified MacNab score indicating the rate of effectiveness at the four-week follow-up. RESULTS: There were no significant post-procedural VAS differences between two groups (P = .252). The effectiveness rate among the patients was 47.8% in DV group, 34.8% in DO group, measured by modified MacNab score. The difference was not statistically significant (P = .117). CONCLUSIONS: A forceful saline injection did not have a significant effect during the treatment of radicular pain. Further studies with greater volumes and with additional techniques would offer a more conclusive perspective.

Successful Treatment of Severe Sympathetically Maintained Pain Following Anterior Spine Surgery

Sympathetic dysfunction is one of the possible complications of anterior spine surgery; however, it has been underestimated as a cause of complications. We report two successful experiences of treating severe dysesthetic pain occurring after anterior spine surgery, by performing a sympathetic block. The first patient experienced a burning and stabbing pain in the contralateral upper extremity of approach side used in anterior cervical discectomy and fusion, and underwent a stellate ganglion block with a significant relief of his pain. The second patient complained of a cold sensation and severe unexpected pain in the lower extremity of the contralateral side after anterior lumbar interbody fusion and was treated with lumbar sympathetic block. We aimed to describe sympathetically maintained pain as one of the important causes of early postoperative pain and the treatment option chosen for these cases in detail.

Effects of clonidine on the activity of the rat glutamate transporter EAAT3 expressed in Xenopus oocytes / 대한마취과학회지

BACKGROUND: Clonidine has been shown to be a potent neuroprotectant by acting at alpha2 receptors on glutamatergic neurons to inhibit the release of glutamate. The aim of this study is to investigate the effects of clonidine on the activity of EAAT3 that can regulate extracellular glutamate. METHODS: EAAT3 was expressed in the Xenopus oocytes. Using a two-electrode voltage clamp, membrane currents were recorded after application of 30 microM L-glutamate both in the presence and absence of various concentrations of clonidine. To determine the effects of clonidine on the Km and Vmax of EAAT3 and the reversibility of clonidine effects, membrane currents were recorded after the application of various concentrations of L-glutamate both in the presence and absence of 1.50 x 10(-7) M clonidine. RESULTS: Clonidine reduced the EAAT3 responses to L-glutamate in a concentration-dependent manner. This inhibition was statistically significant at higher concentrations than at the clinically relevant range. Clonidine at 1.50 x 10(-7) M reduced the Vmax, but did not affect the Km of EAAT3 for L-glutamate. CONCLUSIONS: These results suggest that the direct inhibition of EAAT3 activity is not related to the sedation effect of clonidine and that the clonidine-induced reduction of EAAT3 activity provides additional data for the possible involvement of glutamatergic hyperactivity in the proconvulsant effect of clonidine.