So Yeon Kim

Perioperative administration of pregabalin for pain after robot-assisted endoscopic thyroidectomy: a randomized clinical trial

BackgroundPerioperative administration of pregabalin, which is effective for neuropathic pain, might reduce early postoperative and chronic pain. This randomized, double-blinded, placebo-controlled trial (Clinical Trials.gov ID NCT00905580) was designed to investigate the efficacy and safety of pregabalin for reducing both acute postoperative pain and the development of chronic pain in patients after robot-assisted endoscopic thyroidectomy.MethodsNinety-nine patients were randomly assigned to groups that received pregabalin 150xa0mg or placebo 1 h before surgery, with the dose repeated after 12 h. Assessments of pain and side effects were performed 48 h postoperatively. The incidences of chronic pain and hypoesthesia in the anterior chest were recorded 3xa0months after surgery.ResultsNinety-four patients completed the study. Verbal numerical rating scale scores for pain and the need for additional analgesics were lower in the pregabalin group (nxa0=xa047) than the placebo group (nxa0=xa047) during 48 h postoperatively (Pxa0<xa00.05). However, incidences of sedation and dizziness were higher in the pregabalin group (Pxa0<xa00.05). There were no differences between the groups in the incidences of chronic pain and chest hypoesthesia at 3xa0months after surgery.ConclusionsPerioperative administration of pregabalin (150xa0mg twice per day) was effective in reducing early postoperative pain but not chronic pain in patients undergoing robot-assisted endoscopic thyroidectomy. Caution should be taken regarding dizziness and sedation.

Effect of Dexmedetomidine on Sevoflurane Requirements and Emergence Agitation in Children Undergoing Ambulatory Surgery

Purpose Dexmedetomidine, a potent selective α2-adrenergic agonist, produces sedation and analgesia. This study was conducted to assess the effect of dexmedetomidine infusion on sevoflurane requirements, recovery profiles, and emergence agitation in children undergoing ambulatory surgery. Materials and Methods Forty children undergoing ambulatory hernioplasty or orchiopexy were randomized into two groups. The dexmedetomidine group (Group D, n=20) received dexmedetomidine 1 µg/kg, followed by 0.1 µg/kg/h until the end of surgery, whereas the saline group (Group S, n=20) received volume-matched normal saline. Sevoflurane was used for induction and maintenance of anesthesia and caudal block was performed in all children. End-tidal sevoflurane concentration (ET-sevo), the incidence of emergence agitation, pain scores, and sedation scores were recorded. Hemodynamic changes and other adverse effects were assessed in the perioperative period. Results ET-sevo of Group D was significantly reduced in 23.8-67% compared to Group S during surgery. The incidence of emergence agitation was lower in Group D than in Group S (5% vs. 55%, p=0.001). Postoperative pain was comparable, and discharge time was not different between the groups. Mean arterial pressure and heart rate were significantly lower in Group D during surgery. Conclusion Intraoperative infusion of dexmedetomidine reduced sevoflurane requirements and decreased emergence agitation without delaying discharge in children undergoing ambulatory surgery. However, caution should be taken in regard to bradycardia and hypotension.

Postoperative Intravenous Patient-Controlled Analgesia in Thyroid Surgery: Comparison of Fentanyl and Ondansetron Regimens With and Without the Nonsteriodal Anti-Inflammatory Drug Ketorolac

BACKGROUNDnNonsteroidal anti-inflammatory drugs (NSAIDs), through synergistic action with opioids, can reduce postoperative nausea and vomiting via intravenous patient-controlled analgesia (PCA). We compared the efficacy of three PCA regimens.nnnMETHODSnPatients (n = 135) undergoing thyroidectomy were randomly allocated to three PCA regimens. All groups received 12 mg ondansetron (a serotonin 5-HT(3) receptor antagonist). In addition, Group I received the opioid fentanyl, 15 microg/kg. Group II received fentanyl 12.5 microg/kg and the NSAID ketorolac, 1.5 mg/kg, and Group III received fentanyl 10 microg/kg and ketorolac 3 mg/kg. Pain scores, nausea and vomiting, and dizziness were assessed 1, 6, 12, and 24 hours postoperatively.nnnRESULTSnPain scores were similar among the three groups. However, postoperative nausea and vomiting was significantly lower in groups II and III (p < 0.05) than group I. Postoperative dizziness was significantly lower in group III than groups I and II (p < 0.05).nnnCONCLUSIONSnThe NSAID ketorolac when combined with lower doses of the opioid fentanyl and the same dose of ondansetron is associated with the same analgesic efficacy but less nausea and vomiting after thyroid surgery. A higher ratio of NSAID to opioid, when used as reported here, is associated with less postoperative dizziness.

Effect of propofol post-treatment on blood-brain barrier integrity and cerebral edema after transient cerebral ischemia in rats.

Although propofol has been reported to offer neuroprotection against cerebral ischemia injury, its impact on cerebral edema following ischemia is not clear. The objective of this investigation is to evaluate the effects of propofol post-treatment on blood–brain barrier (BBB) integrity and cerebral edema after transient cerebral ischemia and its mechanism of action, focusing on modulation of aquaporins (AQPs), matrix metalloproteinases (MMPs), and hypoxia inducible factor (HIF)-1α. Cerebral ischemia was induced in male Sprague–Dawley rats (nxa0=xa078) by occlusion of the right middle cerebral artery for 1xa0h. For post-treatment with propofol, 1xa0mgxa0kg−1xa0min−1 of propofol was administered for 1xa0h from the start of reperfusion. Nineteen rats undergoing sham surgery were also included in the investigation. Edema and BBB integrity were assessed by quantification of cerebral water content and extravasation of Evans blue, respectively, following 24xa0h of reperfusion. In addition, the expression of AQP-1, AQP-4, MMP-2, and MMP-9 was determined 24xa0h after reperfusion and the expression of HIF-1α was determined 8xa0h after reperfusion. Propofol post-treatment significantly reduced cerebral edema (Pxa0<xa00.05) and BBB disruption (Pxa0<xa00.05) compared with the saline-treated control. The expression of AQP-1, AQP-4, MMP-2, and MMP-9 at 24xa0h and of HIF-1α at 8xa0h following ischemia/reperfusion was significantly suppressed in the propofol post-treatment group (Pxa0<xa00.05). Propofol post-treatment attenuated cerebral edema after transient cerebral ischemia, in association with reduced expression of AQP-1, AQP-4, MMP-2, and MMP-9. The decreased expression of AQPs and MMPs after propofol post-treatment might result from suppression of HIF-1α expression.

Hyperglycemia Attenuates Myocardial Preconditioning of Remifentanil

BACKGROUNDnHyperglycemia attenuates cardioprotection by remifentanil-preconditioning in ischemia-reperfusion in vivo in diabetic rats. However, the effects of hyperglycemia in cultured ventricular myocytes remains unknown. Therefore, we examined the in vitro effects of hyperglycemia on hypoxia-reoxygenation (H/R) and cardioprotection from remifentanil-preconditioning in isolated neonatal rat ventricular myocytes (NRVMs), including effects on apoptotic signaling pathways and Ca(2+) homeostasis.nnnMATERIALS AND METHODSnNRVMs were cultured in medium with 5.5 mM (normoglycemia) or 25.5 mM glucose for one day. Then, NRVMs in H/R groups were exposed to 1 h of hypoxia and 5 h of reoxygenation with or without remifentanil-preconditioning at 1 μM. Cell viability, apoptosis, and Ca(2+) homeostasis were assessed by MTT assay, caspase-3 assay, confocal microscopy and immunoblots.nnnRESULTSnIn normoglycemia, remifentanil-preconditioning improved the viability of cardiomyocytes (P < 0.01) and prevented the increase of caspase-3 activity and Ca(2+) overload after H/R injury (P < 0.05). In addition, decrease in Akt, ERK1/2, and Bcl-2, and the increase in Bax by H/R was attenuated by remifentanil-preconditioning (P < 0.05). However, in hyperglycemia, the viability was partially impaired after H/R but not improved by remifentanil-preconditioning. Apoptotic activity, Ca(2+) concentration, and apoptotic kinases except Akt were not affected by either H/R or remifentanil-preconditioning under hyperglycemia. Akt phosphorylation was decreased by H/R but not restored by remifentanil preconditioning.nnnCONCLUSIONSnRemifentanil preconditioning under normoglycemia renders NRVMs resistant to H/R injury by reducing apoptosis and intracellular Ca(2+) concentrations. The mechanism appears to be modulation of apoptotic signaling. However, hyperglycemia mitigates H/R injury in NRVMs, and may reduce the protective effect of remifentanil-preconditioning that may be associated with the Akt pathways.

Low-Dose Dexmedetomidine Reduces Emergence Agitation after Desflurane Anaesthesia in Children Undergoing Strabismus Surgery

Purpose Emergence agitation (EA) is frequently observed in children undergoing general anaesthesia. This study tested whether the addition of an intra-operative low-dose infusion of dexmedetomidine to fentanyl treatment reduced the incidence of emergence delirium following desflurane anesthesia in children undergoing strabismus surgery. Materials and Methods A total of 96 children (1-5 years old) undergoing strabismus surgery were enrolled. Anaesthesia was induced with propofol and maintained with desflurane. After induction, fentanyl (1 µg/kg) was administered to all children. During surgery, patients were infused with 0.2 µg/(kg·h)-1 dexmedetomidine (Group FD, n=47) or normal saline (Group F, n=47). Postoperative objective pain score (OPS), Paediatric Agitation and Emergence Delirium (PAED) score, and EA score were documented every 10 minutes in the post-anaesthesia care unit. Results There were no significant differences between the two groups in demographic characteristics and haemodynamic changes. The mean values of maximum EA, maximum PAED, and maximum OPS score were significantly lower in Group FD than in Group F at 0, 10, and 20 minutes after arrival at the post-anaesthesia care unit (p<0.001). The frequency of fentanyl rescue was lower in Group FD than in Group F (p<0.001). The incidence of severe EA was significantly lower in Group FD than in Group F (12.8% vs. 74.5%, p<0.001). Conclusion Intra-operative low-dose infusion of dexmedetomidine in addition to fentanyl reduces EA following desflurane anaesthesia in children undergoing strabismus surgeries.

Effect of dexmedetomidine on the corrected QT and Tp-e intervals during spinal anesthesia.

Purpose The aim of this study is to evaluate the effect of dexmedetomidine on corrected QT (QTc) and Tp-e intervals in patients undergoing spinal anesthesia. Materials and Methods We studied 50 patients who were scheduled to undergo spinal anesthesia before orthopedic surgeries. Patients were allocated to receive either an infusion of dexmedetomidine or normal saline after spinal anesthesia. Results QTc intervals were significantly prolonged after spinal anesthesia, and the prolonged QTc interval returned to baseline values 10 minutes after either normal saline or dexmedetomidine administration in both groups. The QTc interval values after dexmedetomidine administration were significantly shorter compared to the QTc interval values just before dexmedetomidine administration. Conclusion Dexmedetomidine could promote the return of a prolonged QTc interval induced by spinal anesthesia and might be helpful in patients who have a prolonged QTc interval.

Synergistic activation of lipopolysaccharide-stimulated glial cells by propofol.

Despite the extensive use of propofol in general anesthetic procedures, the effects of propofol on glial cell were not completely understood. In lipopolysaccharide (LPS)-stimulated rat primary astrocytes and BV2 microglial cell lines, co-treatment of propofol synergistically induced inflammatory activation as evidenced by the increased production of NO, ROS and expression of iNOS, MMP-9 and several cytokines. Propofol augmented the activation of JNK and p38 MAPKs induced by LPS and the synergistic activation of glial cells by propofol was prevented by pretreatment of JNK and p38 inhibitors. When we treated BV2 cell culture supernatants treated with LPS plus propofol on cultured rat primary neuron, it induced a significant neuronal cell death. The results suggest that the repeated use of propofol in immunologically challenged situation may induce glial activation in brain.

Impact of the interval between coronary angiography and off-pump coronary bypass surgery on postoperative renal function

Background Postoperative acute kidney injury (AKI) is a significant complication after coronary artery bypass surgery. Prior coronary angiography increases the likelihood of AKI due to the use of a radiocontrast dye. This study examined the effect of coronary angiography on the postoperative renal function after off-pump coronary artery bypass surgery (OPCAB). Methods The records of 110 patients who required OPCAB were reviewed. These patients also had at least two of the following conditions: chronic kidney disease, hypertension, diabetes mellitus, emergency surgery, congestive heart failure, age >75 years, hematocrit <30%, a left ventricular ejection fraction <40%, or the use of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers. The patients were divided into two groups; coronary angiography performed within two days of OPCAB (Control group, n = 55), and coronary angiography performed more than two days before OPCAB (Angio group, n = 55). The serum creatinine (SCr) and serum cystatin C levels were measured on the day before surgery, as well as on postoperative days 1, 2, 3 and 7. The estimated glomerular filtration rate (eGFR) was also obtained on those days. AKI was defined as an increase in Cr ≥50% or ≥0.3 mg/dl within 48 hours. Results The postoperative changes in the SCr, cystatin C and eGFR were similar in the two groups. The incidence of AKI and renal replacement therapy were similar in the two groups. Conclusions Coronary angiography performed within two days of OPCAB does not affect the postoperative renal function.

Postoperative Pain and Intravenous Patient-Controlled Analgesia-Related Adverse Effects in Young and Elderly Patients: A Retrospective Analysis of 10,575 Patients

AbstractIn this retrospective analysis of 10,575 patients who used fentanyl-based intravenous patient-controlled analgesia (IV-PCA) after surgery, we evaluated difference between young and elderly patients on their characteristic of adverse effects.We reviewed the data collected from the patients who were provided IV-PCA for pain control following elective surgery under either general or spinal anesthesia between September 2010 and March 2014. Postoperative pain, incidence of PCA-related adverse effects, and risk factors for the need of rescue analgesics and antiemetics for postoperative 48u200ahours were analyzed.Pain intensity (numerical rating scale [NRS]) at postoperative 6 to 12 hours (4.68 vs 4.58, Pu200a<u200a0.01) and incidence of nausea or vomiting (23.8% vs 20.6%, Pu200a<u200a0.001) were higher in young patients, while incidence of PCA discontinuation (9.9% vs 11.5%, Pu200a<u200a0.01) and sedation (0.1% vs 0.7%, Pu200a<u200a0.001) was higher in elderly patients. Despite larger fentanyl dose used, a greater proportion of young patients required rescue analgesics (53.8% vs 47.9%, Pu200a<u200a0.001) while addition of ketorolac was effective in reducing postoperative pain. Despite lower incidence of postoperative nausea and vomiting (PONV), a larger proportion of elderly patients required rescue antiemetics (10.1% vs 12.2%, Pu200a<u200a0.001) while addition of ramosetron was effective in reducing PONV.In conclusion, when fentanyl-based IV-PCA is used for postoperative pain control, a larger proportion of young patients may require rescue analgesics while elderly patients may require more rescue antiemetics. The addition of ketorolac or ramosetron to the PCA of young and elderly patients can be effective to prevent rescue analgesics or antiemetics use.