Jung-Hee Ryu

Controlled hypotension for middle ear surgery: a comparison between remifentanil and magnesium sulphate

BACKGROUNDnThis prospective, randomized study was designed to compare remifentanil and magnesium sulphate during middle ear surgery in terms of postoperative pain and other complications.nnnMETHODSnEighty patients undergoing middle ear surgery were enrolled in the study. Patients were randomized into two groups of 40 to receive remifentanil (Group R) or magnesium sulphate (Group M) infusion. Propofol 2 mg kg(-1) was administered to induce anaesthesia, which was maintained using sevoflurane. Group R received a continuous infusion of remifentanil titrated between 3 and 4 ng ml(-1) using target-controlled infusion, whereas Group M received an i.v. magnesium sulphate bolus of 50 mg kg(-1) followed by a 15 mg kg(-1) h(-1) continuous infusion to maintain a mean arterial pressure (MAP) between 60 and 70 mm Hg. Haemodynamic variables, surgical conditions, postoperative pain, and adverse effects, such as postoperative nausea and vomiting (PONV) and shivering, were recorded.nnnRESULTSnControlled hypotension was well maintained in both groups. MAP and heart rate were higher in Group R than in Group M after operation. Surgical conditions were not different between the two groups. Postoperative pain scores were significantly lower in Group M than in Group R (P<0.05). Seventeen patients in Group R (43%) and seven patients in Group M (18%) developed PONV (P=0.01).nnnCONCLUSIONSnBoth magnesium sulphate and remifentanil when combined with sevoflurane provided adequate controlled hypotension and proper surgical conditions for middle ear surgery. However, patients administered magnesium sulphate had a more favourable postoperative course with better analgesia and less shivering and PONV.

Ramosetron versus ondansetron for the prevention of postoperative nausea and vomiting after laparoscopic cholecystectomy

BackgroundPatients undergoing general anesthesia for laparoscopic cholecystectomy are at high risk for postoperative nausea and vomiting (PONV). This study compared ramosetron and ondansetron in terms of efficacy for PONV prevention after laparoscopic cholecystectomy.MethodsFor this study, 120 patients scheduled to undergo laparoscopic cholecystectomy were randomized (in double-blind fashion) to receive 4xa0mg of ondansetron (group O4, nxa0=xa040), 8xa0mg of ondansetron (group O8, nxa0=xa040), or 0.3xa0mg of ramosetron (group R, nxa0=xa040) intravenously after surgery. Postoperative nausea, retching, vomiting, pain, and side effects were assessed at 2xa0h, 24xa0h, and 48xa0h after surgery.ResultsNo statistical differences were observed among the three groups with regard to patient characteristics and information on surgery and anesthesia. The ratio of complete response (no PONV for 2xa0h) was higher for groups O8 and R than for group O4 as follows: 80% (nxa0=xa032) for groups O8 and R versus 58% (nxa0=xa023) for group O4 during the first postoperative 2xa0h (pxa0=xa00.04), 90% (nxa0=xa036) for groups O8 and R versus 76% (nxa0=xa030) for group O4 over 24xa0h (2–24xa0h) (pxa0=xa00.09), and 98% (nxa0=xa038) for groups O4 and O8 versus 100% (nxa0=xa040) for group R over the next 24xa0h (24–48xa0h) after surgery (pxa0=xa00.36). During the first 2xa0h after surgery, rescue antiemetics were used for significantly fewer patients in groups O8 and R (20%) than in group O4 (42.5%) (pxa0=xa00.04). Postoperative pain and the use of rescue analgesics were comparable among the groups. There was no clinically serious adverse event due to the study drugs.ConclusionRamosetron 0.3xa0mg and ondansetron 8xa0mg are more effective than ondansetron 4xa0mg for the prevention of PONV (2xa0h). Ramosetron 0.3xa0mg is as effective as ondansetron 8xa0mg for the prophylaxis of PONV after laparoscopic cholecystectomy.

Randomized double-blind study of remifentanil and dexmedetomidine for flexible bronchoscopy

BACKGROUNDnThe safety profiles and efficacies of remifentanil and dexmedetomidine (a sedative-analgesic without respiratory depression) for sedation during flexible bronchoscopy were investigated.nnnMETHODSnSeventy-two patients undergoing elective flexible bronchoscopy were randomly assigned to a propofol-remifentanil group (Group PR, n=36) or a propofol-dexmedetomidine group (Group PD, n=36). The primary outcome was the incidence of oxygen desaturation. Haemodynamic variables, adverse events, need of oral cavity suction, cough scores, satisfaction scores of patients and bronchoscopists, levels of sedation, and recovery times were also compared.nnnRESULTSnThe incidence of oxygen desaturation was significantly lower in the PD group than in the PR group (P=0.01). There were no significant differences between groups in terms of level of sedation, oxygen saturation, mean arterial pressure, heart rate over time, cough scores, or patient satisfaction scores (P>0.05). However, cough scores and bronchoscopist satisfaction scores (P<0.01) were lower in the PD group. In addition, topical anaesthesia (P<0.01) was required more frequently and recovery time (P=0.00) was significantly longer in the PD group. However, oral suction (P=0.03) was required less frequently in the PD group.nnnCONCLUSIONSnDexmedetomidine was associated with fewer incidents of oxygen desaturation and a reduced need for oral cavity suction than remifentanil during flexible bronchoscopy. However, dexmedetomidine was associated with a longer recovery time and poorer bronchoscopist satisfaction score.

Effects of magnesium sulphate on intraoperative neuromuscular blocking agent requirements and postoperative analgesia in children with cerebral palsy

BACKGROUNDnIn this double-blind, randomized, placebo-controlled study, we evaluated the effects of magnesium sulphate on neuromuscular blocking agent requirements and analgesia in children with cerebral palsy (CP).nnnMETHODSnWe randomly divided 61 children with CP undergoing orthopaedic surgery into two groups. The magnesium group (Group M) received magnesium sulphate 50 mg kg(-1) i.v. as a bolus and 15 mg kg(-1) h(-1) by continuous infusion during the operation. The control group (Group S) received the same amount of isotonic saline. Rocuronium was administered 0.6 mg kg(-1) before intubation and 0.1 mg kg(-1) additionally when train-of-four counts were 2 or more. I.V. fentanyl and ketorolac were used to control postoperative pain. Total infused analgesic volumes and pain scores were evaluated at postoperative 30 min, and at 6, 24, and 48 h.nnnRESULTSnThe rocuronium requirement of Group M was significantly less than that of Group S [0.29 (0.12) vs 0.42 (0.16) mg kg(-1) h(-1), P<0.05]. Cumulative analgesic consumption in Group M was significantly less after operation at 24 and 48 h (P<0.05), and pain scores in Group M were lower than in Group S during the entire postoperative period (P<0.05). Serum magnesium concentrations in Group M were higher until 24 h after operation (P<0.05). The incidence of postoperative nausea and vomiting and rescue drug injections was similar in the two groups. No shivering or adverse effects related to hypermagnesaemia were encountered.nnnCONCLUSIONSnI.V. magnesium sulphate reduces rocuronium requirements and postoperative analgesic consumption in children with CP.

Efficacy of butylscopolamine for the treatment of catheter-related bladder discomfort: a prospective, randomized, placebo-controlled, double-blind study

BACKGROUNDnCatheter-related bladder discomfort (CRBD) secondary to intraoperative catheterization of urinary bladder is one of the most distressing symptoms during recovery from anaesthesia. Butylscopolamine, a peripheral antimuscarinic agent, is effective for relieving the pain, which is because of smooth muscle contraction. The aim of this study was to assess the efficacy and safety profiles of butylscopolamine in treating CRBD after urological surgeries.nnnMETHODSnAdult male patients undergoing urological surgery requiring urinary bladder catheterization intraoperatively were enrolled. Induction and maintenance of anaesthesia were standardized. Patients were randomized into two groups after complaining of CRBD in the post-anaesthesia care unit. The control group (n=29) received normal saline and the butylscopolamine group (n=28) was administered butylscopolamine 20 mg i.v. The severity of CRBD, postoperative pain, and adverse effects were assessed at baseline, 20 min, 1, 2, and 6 h after administration of the study drug.nnnRESULTSnThe severity of CRBD observed in the butylscopolamine group was significantly lower than that of the control group at 1, 2, and 6 h after administration of the study drug [59 (12), 50 (16), 40 (21) in the control group vs 41 (22), 32 (25), 23 (18) in the butylscopolamine group, P<0.01]. Rescue analgesics were required less in the butylscopolamine group than in the control group (P=0.001). Adverse events were comparable between the two groups.nnnCONCLUSIONnButylscopolamine 20 mg administered i.v. after complaining CRBD during recovery reduced both the severity of CRBD and the need for rescue analgesics without adverse effects in patients undergoing urologic surgeries.

Influence of the timing of administration of crystalloid on maternal hypotension during spinal anesthesia for cesarean delivery: preload versus coload

BackgroundProphylactic fluid preloading before spinal anesthesia has been a routine procedure to prevent maternal hypotension during cesarean delivery. Unlike colloid, timing of infusion of crystalloid may be important because of its short stay in intravascular space. We hypothesized that crystalloid loading just after intrathecal injection compared to preload would be more effective in preventing maternal hypotension.MethodsIn this prospective controlled study, sixty parturients were randomized to receive 15xa0ml/kg of crystalloid before (preload group) or after (coload group) intrathecal drug injection for spinal anesthesia. Hypotension was defined if systolic arterial pressure decreased below 80% of baseline and ephedrine was administered to treat hypotension. The incidence of hypotension and the total dose of ephedrine were checked. Blood pressure, heart rate and nausea before childbirth were assessed. Neonatal outcomes were evaluated with Apgar scores and umbilical blood gas analysis.ResultsThe incidence of hypotension was lower in the coload group compared to the preload group (53% vs. 83%, Pu2009=u20090.026). The blood pressure showed the bigger drop during spinal anesthesia in the preload group (34u2009±u200913 vs. 25u2009±u200910xa0mmHg, Pu2009=u20090.002) and smaller dose of ephedrine was required in the coload group (7.5 [0–30] vs. 15 [0–40] mg, Pu2009=u20090.015). The incidence of nausea was also lower in the coload group (27% vs. 60%, Pu2009=u20090.019). Neonatal outcome measures were comparable between two groups.ConclusionsIn case of using crystalloids for cesarean delivery, coload is more effective than preload for the prevention of maternal hypotension after spinal anesthesia.Trial registrationClinical Research Information Service KCT0000324 (Jan 12th, 2012)

Caffeine-induced inhibition of the activity of glutamate transporter type 3 expressed in Xenopus oocytes.

Caffeine has been known to trigger seizures, however, the precise mechanism about the proconvulsive effect of caffeine remains unclear. Glutamate transporters play an important role to maintain the homeostasis of glutamate concentration in the brain tissue. Especially, dysfunction of excitatory amino acid transporter type 3 (EAAT3) can lead to seizures. We investigated the effects of caffeine on the activity of EAAT3 and the involvement of protein kinase C (PKC) and phosphatidylinositol 3-kinase (PI3K). Rat EAAT3 was expressed in Xenopus oocytes by injecting EAAT3 mRNA. l-Glutamate (30μM)-induced inward currents were recorded via the two-electrode voltage clamp method. Caffeine decreased EAAT3 activity in a dose-dependent manner. Caffeine (30μM for 3min) significantly reduced V(max), but did not alter K(m) value of EAAT3 for glutamate. When preincubated oocytes with phorbol-12-myristate-13-acetate (PMA, a PKC activator) were exposed to caffeine, PMA-induced increase in EAAT3 activity was abolished. Two PKC inhibitors (chelerythrine and staurosporine) significantly reduced basal EAAT3 activity. Whereas, there were no significant differences among the PKC inhibitors, caffeine, and PKC inhibitors+caffeine groups. In similarly fashion, wortmannin (a PI3K inhibitor) significantly decreased EAAT3 activity, however no statistical differences were observed among the wortmannin, caffeine, and wortmannin+caffeine groups. Our results demonstrate that caffeine attenuates EAAT3 activity and this reducing effect of caffeine seems to be mediated by PKC and PI3K.

Effects of pregabalin on the activity of glutamate transporter type 3

BACKGROUNDnPregabalin, (S)-3-aminomethyl-5-methyl hexanoic acid, is a ligand for the α2δ subunit (a component of voltage-gated calcium channels) and has analgesic and anticonvulsant properties. Glutamate uptake by glutamate transporters may be a mechanism for these properties. We investigated the effects of pregabalin on the activity of the neuronal glutamate transporter type 3 (EAAT3).nnnMETHODSnEAAT3 was expressed in Xenopus laevis oocytes. Two-electrode voltage clamping was used to record membrane currents before, during, and after applying l-glutamate (30 μM) in the presence or absence of pregabalin. Currents were also measured in oocytes pretreated with a protein kinase C (PKC) activator (phorbol-12-myristate-13-acetate, PMA), PKC inhibitors (chelerythrine or staurosporine), or a phosphatidylinositol-3-kinase (PI3K) inhibitor wortmannin.nnnRESULTSnThe exposure of the oocytes injected with EAAT3 mRNA to serial concentrations of pregabalin (0.06-60 μM) significantly increased their responses to 30 μM l-glutamate. A kinetic study showed that pregabalin significantly increased V(max) without changing K(m). Treatment of oocytes with PMA, pregabalin, or pregabalin plus PMA significantly increased transporter currents vs controls, but treatment with PMA plus pregabalin did not increase the responses further vs PMA or pregabalin alone. In addition, pretreatment of oocytes with two PKC inhibitors (chelerythrine or staurosporine), or inhibitor wortmannin, significantly reduced basal and pregabalin-enhanced EAAT3 activity.nnnCONCLUSIONSnPregabalin increased EAAT3 activity and PKC and PI3K were involved. This may explain the analgesic effect of pregabalin in neuropathic pain.

Intravenous, Oral, and the Combination of Intravenous and Oral Ramosetron for the Prevention of Nausea and Vomiting After Laparoscopic Cholecystectomy: A Randomized, Double-Blind, Controlled Trial

BACKGROUNDnPatients undergoing general anesthesia for laparoscopic cholecystectomy have a high risk of postoperative nausea and vomiting (PONV) with incidences up to 75%. Ramosetron, a serotonin subtype 3 (5-HT(3)) antagonist, has been shown to be effective as an antiemetic after chemotherapy and surgery. Consensus guidelines recommend a combination of antiemetic therapies in high-risk groups. Until now, no published data have been available on the use of combination oral plus intravenous ramosetron.nnnOBJECTIVEnThe goal of this prospective, randomized, double-blind study was to compare the efficacy and tolerability of intravenous, oral, and the combination of oral and intravenous ramosetron for PONV prophylaxis in patients undergoing laparoscopic cholecystectomy.nnnMETHODSnPatients scheduled for laparoscopic cholecystectomy were double-randomly allocated to 1 of 3 groups. Patients were randomly allocated to receive either 0.3 mg of intravenous ramosetron (group A), 0.1 mg of oral ramosetron (group B), or the combination of 0.1 mg of oral ramosetron and 0.3 mg of intravenous ramosetron (group C). All patients received standardized balanced anesthesia with desflurane and remifentanil. Postoperative nausea, retching, vomiting, pain, and adverse effects were assessed at 0 to 2, 2 to 24, and 24 to 48 hours after surgery.nnnRESULTSnA total of 124 Korean patients (67 women, 57 men; age range, 25-65 years) were randomized to 1 of 3 study groups (42 in group A [mean age, 49.8 years], 41 in group B [mean age, 47.4 years], and 41 in group C [mean age, 48.9 years]). No statistical differences were observed among the 3 groups with regard to patient characteristics and information on surgery and anesthesia. During postoperative period 0 to 2 hours, complete response occurred in 31 (74%) patients in group A, 27 (66%) in group B, and 37 (90%) in group C. During the postoperative period of 2 to 24 hours, complete response was observed in 36 (86%), 33 (80%), and 40 (98%) patients in groups A, B, and C, respectively; there was a statistically significant difference in group C compared with group A or group B. During the postoperative period of 0 to 48 hours, incidences of rescue antiemetic use were 13 (31%), 14 (34%), and 3 (7%) in groups A, B and C, respectively. Common adverse effects (headache, dizziness, and drowsiness) were observed, but there was no significant difference in the incidences of adverse effects among the 3 groups (P > 0.05).nnnCONCLUSIONSnThe combination of 0.1-mg oral and 0.3-mg intravenous ramosetron was more effective than either 0.3-mg intravenous ramosetron or 0.1-mg oral ramosetron alone for the prophylaxis of nausea and vomiting after laparoscopic cholecystectomy during the first 24 hours after surgery. In addition, differences did not reach the level of statistical significance between 0.1 mg of oral ramosetron and 0.3 mg of intravenous ramosetron for the prevention of PONV in this patient population. Oral, intravenous, and combined oral and intravenous ramosetron appears well tolerated in the population studied. ClinicalTrials.gov identifier: NCT 01041183.

Effects of intraoperative protective lung ventilation on postoperative pulmonary complications in patients with laparoscopic surgery: prospective, randomized and controlled trial

AbstractBackgroundnRespiratory functions are usually impaired during pneumoperitoneum for laparoscopic surgery. This randomized, controlled and single-blinded study was performed to evaluate whether intraoperative protective lung ventilation influences postoperative pulmonary complications after laparoscopic hepatobiliary surgery.MethodsSixty-two patients were randomized to receive either conventional ventilation with alveolar recruitment maneuver (tidal volume of 10xa0ml/kg with inspiratory pressure of 40 cmH2O for 30xa0s after the end of pneumoperitoneum, group R), or protective lung ventilation (low tidal volume of 6xa0ml/kg with positive end-expiratory pressure [PEEP] of 5 cmH2O, group P). Induction and maintenance of anesthesia were done with balanced anesthesia. Respiratory complications such as atelectasis, pneumonia or desaturation were observed postoperatively. The length of hospital stay, arterial blood gas analysis, peak inspiratory pressure and hemodynamic variables were also recorded. Results are presented as meanxa0±xa0SD or number of patients (%).ResultsPostoperative pulmonary complications (Pxa0=xa00.023) and desaturation below 90xa0% (Pxa0=xa00.016) occurred less frequently in group P than in group R. Eight patients of group R and 3 patients of group P showed atelectasis. Pneumonia was diagnosed in 1 patient of group R. No differences were observed in the length of hospital stay, arterial blood gas analysis (pH, PaO2, PaCO2 and PAO2) and hemodynamic variables except PAO2, AaDO2 and peak inspiratory pressure between the two groups.ConclusionProtective lung ventilation (low tidal volume with PEEP) during pneumoperitoneum was associated with less incidences of pulmonary complications than conventional ventilation with alveolar recruitment maneuver after laparoscopic hepatobiliary surgery.