Remifentanil For Analgesia Research Articles

6287202 Variable dosing of remifentanil analgesia during labour

6287202 Variable dosing of remifentanil analgesia during labour

Neonatal Outcomes in Labor After Intravenous Remifentanil Analgesia vs. Epidural Analgesia: A Retrospective Observational Study.

Background Some evidence indicates that maternal analgesia during labor may have adverse effects on neonates due to exposure to specific drugs or the potential effects of analgesia on the course of labor. We assessed the clinical outcome of term neonates born to mothers who received epidural analgesia (E) or systemic analgesia with remifentanil (R) during labor. Methods Data was collected retrospectively over one year. We have evaluated the medical records of 247 full-term neonates; 208 were born to mothers who received E and 39 to mothers who received R. Data on Apgar scores and neonatal complications(perinatal asphyxia, respiratory distress, infection, hyperbilirubinemia, and birth injuries), and average hospital stay were collected. Mann-Whitney U test, chi-square test, and logistic regression analysis were used where appropriate. Results The values of the mean Apgar scores between E and R at 1 and 5 minutes were similar (8.83 vs. 8.97,p= 0.252; 9.81 vs. 9.87,p= 0.762, respectively). The average length of neonatal hospitalization did not differ between groups (4.19 vs. 4;p= 0.557). The percentages of neonates with any complication were similar between groups (28.3% vs. 32.5%,p= 0.598). Neonates born by cesarean delivery (CD) had significantly worse outcomes than those born vaginally (p= 0.008, OR 2.8, 95% CI [1.30, 6.17]). Conclusion We did not find a statistically significant difference in mean Apgar scores and neonatal complications between neonates who received epidural vs. remifentanil analgesia. An increased rate of complications in neonates born via CD was found. Future studies should have a larger sample size and be powered to detect associations in these findings.

Effect of Remifentanil on Active Phase Duration of Labor in Nulliparous Pregnant Women: A Cross-sectional Study

Objectives: Due to the increase in elective cesarean section and its high complications, epidural analgesia is the gold standard for reducing the pain of vaginal delivery. In contraindication cases, other effective and safe analgesic methods such as remifentanil are suggested. The present study aimed to compare the duration of active phase of labor at stages I and II, as well as neonatal Apgar score following the use of remifentanil analgesia. Materials and Methods: In this study, 120 healthy primiparous women who were candidates for vaginal delivery were selected. After matching for age and body mass index (BMI), the participants were assigned into two equal groups (n=60 each) of intervention (receiving remifentanil) and control. We compared the duration of active phase of labor at stages I and II, neonatal Apgar scores, and the cesarean section rate between the groups. Statistical analysis was performed using SPSS software (version 23). Results: There was no statistically significant difference between the two groups in terms of the duration of active phase in the first and second stages of labor (P=0.84 and P=0.78, respectively), 1-minute Apgar score (P=0.95), 5-min Apgar score (P=0.92), and the rate of cesarean section (P=0.067). Moreover, we observed no maternal complications with remifentanil. Conclusions: According to our results, remifentanil did not increase the duration of labor, rate of cesarean section, and maternal complications. Hence, it can be a good alternative in cases where epidural analgesia is contraindicated.

Efficacy and Safety of Ciprofol Sedation in ICU Patients Undergoing Mechanical Ventilation: A Multicenter, Single-Blind, Randomized, Noninferiority Trial.

To determine the effectiveness and safety of ciprofol for sedating patients in ICUs who required mechanical ventilation (MV). A multicenter, single-blind, randomized, noninferiority trial. Twenty-one centers across China from December 2020 to June 2021. A total of 135 ICU patients 18 to 80 years old with endotracheal intubation and undergoing MV, who were expected to require sedation for 6-24 hours. One hundred thirty-five ICU patients were randomly allocated into ciprofol (n = 90) and propofol (n = 45) groups in a 2:1 ratio. Ciprofol or propofol were IV infused at loading doses of 0.1 mg/kg or 0.5 mg/kg, respectively, over 4 minutes ± 30 seconds depending on the physical condition of each patient. Ciprofol or propofol were then immediately administered at an initial maintenance dose of 0.3 mg/kg/hr or 1.5 mg/kg/hr, to achieve the target sedation range of Richmond Agitation-Sedation Scale (+1 to -2). Besides, continuous IV remifentanil analgesia was administered (loading dose: 0.5-1 μg/kg, maintenance dose: 0.02-0.15 μg/kg/min). Of the 135 patients enrolled, 129 completed the study. The primary endpoint-sedation success rates of ciprofol and propofol groups were 97.7% versus 97.8% in the full analysis set (FAS) and were both 100% in per-protocol set (PPS). The noninferiority margin was set as 8% and confirmed with a lower limit of two-sided 95% CI for the inter-group difference of -5.98% and -4.32% in the FAS and PPS groups. Patients who received ciprofol had a longer recovery time (p = 0.003), but there were no differences in the remaining secondary endpoints (all p > 0.05). The occurrence rates of treatment-emergent adverse events (TEAEs) or drug-related TEAEs were not significantly different between the groups (all p > 0.05). Ciprofol was well tolerated, with a noninferior sedation profile to propofol in Chinese ICU patients undergoing MV for a period of 6-24 hours.

Cesarean Section Can Be Related With Postpartum Depression: A Cross-sectional Study

Objectives: Depression is highly prevalent during pregnancy and after childbirth, and many factors, including the type of delivery, can contribute to developing this condition. Considering the increased use of remifentanil in painless labor and the need for conducting more studies on the consequences of this method this study aimed to determine the mean score of postpartum depression in women giving birth by either remifentanil-induced painless delivery or elective cesarean section. Materials and Methods: The present study was a longitudinal investigation conducted on140 women referred to private hospitals, Tabriz, Iran, between 2020 and 2021 in two groups: women with elective cesarean delivery and women with vaginal delivery with remifentanil analgesia (n=70/each). Depression during pregnancy was assessed at 35-37th weeks’ gestation, and postpartum depression was determined four weeks after childbirth using the Edinburgh Postnatal Depression Scale (EPDS). Independent t test and paired t test were used to compare depression scores. Results: Postpartum depression was significantly higher in women who had undergone a cesarean section than in those giving birth by remifentanil-induced painless vaginal delivery (P = 0.009). Conclusions: The prevalence of postpartum depression was higher in women who underwent elective cesarean section than women who underwent painless vaginal delivery with remifentanil. Considering the steady rise in worldwide cesarean section rate and the health burden and consequences of postpartum depression on mothers and children, health legislators should take measures to reduce women’s tendency towards the cesarean section in the long run.

Comparing the Experiences of Parturient Women With Remifentanil Analgesia and Elective Cesarean Section and Providing Improver Strategies: A Sequential Explanatory Mixed Method Study Protocol

Objectives: Women’s experience during childbirth can affect various aspects (psychological and physical), which has not yet been done accurately. The current study aimed to compare experiences of parturient women with remifentanil analgesia and elective cesarean section (C-section) and provide improver strategies for women living in Tabriz, Iran. Methods: This is a mixed-method study with an explanatory sequential approach. The first stage is quantitative and longitudinal. Participants will be divided into two groups of elective C-sections and parturient women who receive remifentanil. They will be matched concerning social class, type of provider, and birth rank. In the first stage, data will be collected using a socio-demographic questionnaire, Edinburgh’s Depression during pregnancy questionnaire, Labor Agentry Scale, and midwifery-neonatal outcomes checklist within 24 hours after delivery. Participants will be followed up to 30 days after delivery to complete the Edinburgh Postpartum Depression questionnaire. The second stage is a qualitative study to explain the perceptions of parturient women who had either elective C-section or painless delivery (using remifentanil), including factors related to labor experiences. In the third stage, a mixed study will be performed to provide strategies for improving labor experiences. Discussion: Women’s experiences during cesarean section can have different effects on maternal and neonatal outcomes; Following the use of two methods of continuous analgesia with remifentanil and spinal anesthesia and analgesia caused by these methods in cesarean section, women’s experiences may be different; The protocol presented in this study is a clinical guide to present this important issue (experiences of women during cesarean section looking for an appropriate method of analgesia). Ethical Code: IR.TBZMED.REC.1399.521, Pazhoohan Code: 65454.

Predicting anesthetic infusion events using machine learning

Recently, research has been conducted to automatically control anesthesia using machine learning, with the aim of alleviating the shortage of anesthesiologists. In this study, we address the problem of predicting decisions made by anesthesiologists during surgery using machine learning; specifically, we formulate a decision making problem by increasing the flow rate at each time point in the continuous administration of analgesic remifentanil as a supervised binary classification problem. The experiments were conducted to evaluate the prediction performance using six machine learning models: logistic regression, support vector machine, random forest, LightGBM, artificial neural network, and long short-term memory (LSTM), using 210 case data collected during actual surgeries. The results demonstrated that when predicting the future increase in flow rate of remifentanil after 1 min, the model using LSTM was able to predict with scores of 0.659 for sensitivity, 0.732 for specificity, and 0.753 for ROC-AUC; this demonstrates the potential to predict the decisions made by anesthesiologists using machine learning. Furthermore, we examined the importance and contribution of the features of each model using Shapley additive explanations—a method for interpreting predictions made by machine learning models. The trends indicated by the results were partially consistent with known clinical findings.

Remimazolam: a short-acting benzodiazepine for procedural sedation.

The ultra-short-acting opioid analgesic remifentanil provided the approach that was used in the synthesis of remimazolam. A carboxylic ester was incorporated into the benzodiazepine structure providing a resultant compound that is rapidly broken down in the body into a breakdown product that is inactive, thus ensuring a very short-acting benzodiazepine. Remimazolam is highly selective in its action, only having activity at the GABAA receptor. It has been shown to be highly effective in providing sedation for bronchoscopy and colonoscopy without having a prolonged duration of action, therefore having a short effect until patients are fully awake and ready for discharge.

Impact of concurrent remifentanil on the sedative effects of remimazolam, midazolam and propofol in cynomolgus monkeys

Drug-drug interactions can substantially change pharmacological effects of the individual substances involved. For the use of sedatives or anaesthetics, having knowledge of the extent and characteristics of such interactions is crucial for ensuring the proper protection of patients undergoing any kind of sedation.Remimazolam is a new ultra-short acting benzodiazepine that is currently under development for intravenous use in procedural sedation and general anaesthesia. It exhibits a fast onset and fast offset which enables a more rapid recovery than currently available drugs in that class, such as midazolam. The purpose of this study was to more closely investigate the sedative properties and pharmacodynamic drug-drug interaction potential of remimazolam with the opioid analgesic remifentanil and compare it with other commonly used sedatives - midazolam and propofol. For this purpose, six Cynomolgus monkeys received escalating doses of remimazolam, propofol, and midazolam intravenously without or with concurrent remifentanil. Sedation was evaluated using a general sedation scale that included monitoring exploratory and avoidance behaviour, responses to sensory stimuli, posture and gait, and eyelid position as endpoints. Based on the results, sedative doses were calculated to allow evaluation of pharmacological drug-drug interaction with remifentanil.Remimazolam induced dose-dependent and consistent sedative effects in each endpoint tested and showed a high degree of synergism with remifentanil. Midazolam showed a comparable synergism while the interaction between propofol and remifentanil was less pronounced.

Remifentanil up-regulates HIF1α expression to ameliorate hepatic ischaemia/reperfusion injury via the ZEB1/LIF axis.

Ischaemia/reperfusion (I/R)‐induced hepatic injury is regarded as a main reason of hepatic failure after transplantation or lobectomy. The current study aimed to investigate how the opioid analgesic remifentanil treatment affects I/R‐induced hepatic injury and explore the possible mechanisms related to HIF1α. Initially, an I/R‐induced hepatic injury animal model was established in C57BL/6 mice, and an in vitro hypoxia‐reoxygenation model was constructed in NCTC‐1469 cells, followed by remifentanil treatment and HIF1α silencing treatment. The levels of blood glucose, lipids, alanine transaminase (ALT) and aspartate transaminase (AST) in mouse serum were measured using automatic chemistry analyser, while the viability and apoptosis of cells were detected using CCK8 assay and flow cytometry. Our results revealed that mice with I/R‐induced hepatic injury showed higher serum levels of blood glucose, lipids, ALT and AST and leukaemia inhibitory factor (LIF) expression, and lower HIF1α and ZEB1 expression (P < .05), which were reversed after remifentanil treatment (P < .05). Besides, HIF1α silencing increased the serum levels of blood glucose, lipids, ALT and AST (P < .05). Furthermore, hypoxia‐induced NCTC‐1469 cells exhibited decreased HIF1α and ZEB1 expression, reduced cell viability, as well as increased LIF expression and cell apoptosis (P < .05), which were reversed by remifentanil treatment (P < .05). Moreover, HIF1α silencing down‐regulated ZEB1 expression, decreased cell viability, and increased cell apoptosis (P < .05). ZEB1 was identified to bind to the promoter region of LIF and inhibit its expression. In summary, remifentanil protects against hepatic I/R injury through HIF1α and downstream effectors.

Effect of transcutaneous electrical acupoint stimulation combined with general anesthesia on intraoperative and postoperative recovery in patients undergoing carotid artery stenting

Objective To investigate the effect of transcutaneous electrical acupoint stimulation (TEAS) combined with general anesthesia on intraoperative medication and postoperative recovery in patients undergoing carotid artery stenting (CAS). Methods Eighty-two patients with CAS under general anesthesia were randomly divided into the transcutaneous electrical acupoint stimulation combined with general anesthesia group (group T, n=40) and the traditional general anesthesia control group (group C, n=42). The surgical side acupoints of the body for acupuncture were selected as, Shuigou and Baihui, Hegu and Waiguan. For patients in group T, the electrodes were pateched pasted at the corresponding locations and were stimulated by HANS. For the patients in group C, the electrodes were placed at the same location but not stimulated by HANS. The blood pressure and heart rate are maintained within in the (1±20)% range of the baseline. The hemodynamic changes during the operation, the use of vasoactive drugs and the postoperative recovery of the patients were recorded. Results After 30 min of the transcutaneous electrical acupoint stimulation, the blood pressure in the group T was lower than the level of baseline (P 0.05). At 5 min before extubation and 5 min after extubation, the heart rate of patients in group T was lower than that of patients in group C (P 0.05). There was no statistical difference in among the number of cases and total amount of dopamine, atropine and urapidil in the two groups (P>0.05). The amount of remifentanil used in group T was less than that in group C (P 0.05). The time of respiration recovery, wake-up time and extubation time in the group T were less than those in group C (P 0.05). The numbers of patients with postoperative moderate pain (VAS score more than 4 points above) were analyzed at 9 am and 4 pm at one day after the operation. The incidence of postoperative moderate pain in group T was significantly lower than the incidence in group C (P<0.05). Conclusions TEAS combined with general anesthesia for CAS surgery can stabilize hemodynamics changes, reduce analgesic remifentanil consumption, shorten the wake-up time and extubation time after surgery, reduce the incidence of postoperative pain, and improve the patients′ satisfaction with anesthesia. Key words: Transcutaneous electrical acupoint stimulation; Carotid artery stenting; Anesthesia, general; Postoperative recovery

Influence of Different Methods of Intrapartum Analgesia on the Progress of Labour and on Perinatal Outcome.

Background Various methods of intrapartum analgesia are available these days. Pethidine, meptazinol and epidural analgesia are among the most commonly used techniques. A relatively new one is patient-controlled intravenous analgesia with remifentanil, although the experiences published so far in Germany are limited. Our goal was to study the influence of these analgesic techniques (opioids vs. patient-controlled intravenous analgesia with remifentanil vs. epidural analgesia) on the second stage of labour and on perinatal outcome. Material and Methods We conducted a retrospective study with 254 parturients. The women were divided into 4 groups based on the analgesic technique and matched for parity, maternal age and gestational age (opioids n = 64, patient-controlled intravenous analgesia with remifentanil n = 60, epidural analgesia n = 64, controls without the medicinal products mentioned n = 66). Maternal, fetal and neonatal data were analysed. Results The expulsive stage was prolonged among both primiparas and multiparas with patient-controlled intravenous analgesia with remifentanil (79 [74] vs. 44 [55] min, p = 0.016, and 28 [68] vs. 10 [11] min, p < 0.001, respectively) and epidural analgesia (90 [92] vs. 44 [55] min, p = 0.004, and 22.5 [73] vs. 10 [11] min, p = 0.003, respectively) compared with the controls. The length of the pushing stage was similar among primiparas in all groups but prolonged compared with the controls in multiparas with patient-controlled intravenous analgesia with remifentanil (15 [17] vs. 5 [7] min, p = 0.001) and epidural analgesia (10 [15] vs. 5 [7] min, p = 0.006). The Apgar, umbilical arterial pH and base excess values were similar between the groups, as were the rates of acidosis and neonatal intensive care unit admission. Conclusion Parturients with patient-controlled intravenous analgesia with remifentanil and epidural analgesia showed a prolonged expulsive stage compared with the opioid group and controls. The short-term neonatal outcome was not influenced by the three methods examined.

Labor analgesia: Comparison of epidural patient-controlled analgesia and intravenous patient-controlled analgesia

In our study, patient controlled epidural analgesia (PCEA) and patient controlled intravenous remifentanil analgesia (PCIVA) were compared for VAS, and also their side effects on mother and newborn. In this study, 37 pregnant women with a single fetus, who had labor analgesia, were divided into groups of PCIVA (Group 2) and PCEA (Group 1). Bupivacaine 1.25 mg/ml and fentanyl 2 mcg/ml in 100 ml epidural solution were prepared for Group 1. The infusion dose was 15 ml, 5 ml divided doses. We set 5 ml/h basal infusion, 5 ml patient-controlled bolus and 20 min lock time. We prepared 2 mg remifentanil in 100 ml intravenous solution for Group 2. We set 20 mcg/h infusion, 0.05mcg/kg patient-controlled bolus and five min lock time. VAS, maternal-fetal heart rate, blood pressure, oxygen saturation, nausea-vomiting and sedation were recorded during labor. We recorded Apgar scores and maternal satisfaction at the end of labor. The findings showed that both groups could provide adequate analgesia. However, VAS scores were higher in Group PCIVA. The mother satisfaction and newborn's Apgar scores were similar. In both groups, desaturation, which is requiring oxygen support, was not determined. The oxygen saturations were lower in Group 2. The side effects and patient satisfaction were similar in both groups. Although PCIVA was found to be satisfactory concerning maternal satisfaction, VAS after 2nd hour were higher compared to PCEA. PCEA is the gold standard in labor analgesia. However, we believe that PCIVA is a good alternative to epidural analgesia in cases where epidural analgesia is contraindicated or where the patient does not want an epidural.

Recovery of Endothelial Function after Minor-to-Moderate Surgery Is Impaired by Diabetes Mellitus, Obesity, Hyperuricemia and Sevoflurane-Based Anesthesia.

Endothelial dysfunction is observed in several cardiovascular diseases, where endothelium-dependent vasodilation is impaired by oxidative stress. However, the time course of endothelial function during the perioperative period of a minor-to-moderate surgery, and the effects of atherosclerotic risk factors and employed general anesthetics on recovery of endothelial function, are unknown. Endothelial function of 30 patients was evaluated as the reactive hyperemia index (RHI) of reactive hyperemia peripheral arterial tonometry. RHI was measured on day before surgery (control), immediately after surgery (Day 0), day after surgery (Day 1), and day 4 after surgery (Day 4) in patients with no functional limitations who were scheduled for oral and maxillofacial surgery of around 3 hours. Sevoflurane- or propofol-based anesthesia supplemented with an opioid analgesic remifentanil was employed. The control RHI was 2.26 ± 0.64. The RHI significantly decreased to the lowest level on Day 0 (1.52 ± 0.28), recovered on Day 1 (2.07 ± 0.58), and improved further on Day 4 (2.55 ± 0.83). Multiple linear regression analysis revealed that recovery of the RHI from Day 0 to Day 4 was impaired by diabetes mellitus (P = 0.0313), obesity (BMI ≥ 25; P = 0.0166), hyperuricemia (uric acid ≥ 6.0 mg/dL; P = 0.0416) and sevoflurane-based anesthesia (P = 0.0308). These findings suggest that endothelial function as evaluated by the RHI is severely suppressed on the day of a minor-to-moderate surgery, and that it improves until the 4th postoperative day on average. Recovery of endothelial function is impaired by diabetes mellitus, obesity, hyperuricemia, and sevoflurane-based anesthesia.

Labor analgesia in Czech Republic and Slovakia: a 2015 national survey

BackgroundThe purpose of this international survey was to describe the current practices and techniques of labor analgesia in the Czech Republic (CZE) and Slovakia (SVK). MethodsAll Czech and Slovak departments that provide obstetric anesthesia were invited to participate in a one-month (November 2015) prospective study that monitored in detail all peripartum anesthetic procedures delivered by anesthesiologists. Participating centers recorded all data on-line in the CLADE-IS database (Masaryk University, CZE). ResultsThe response rate was 71% (70 of 95 departments in CZE, 35 of 54 centers in SVK). Participating centers represented 87.7% of all births in CZE and 66.4% of all births in SVK during the study period. Analgesia for labor, administered by anesthesiologists, was recorded in 12.5% of deliveries (CZE 12.1%, SVK 13.4%). Epidural analgesia was used in most of the cases (CZE 97.2%, SVK 99.1%) whereas spinal (CZE 1.4%, SVK 0.9%) or combined spinal-epidural (CZE 0.5%, SVK 0.0%) and intravenous remifentanil analgesia (CZE 2.4%, SVK 0.0%) were used infrequently. One fifth of the labors with analgesia administered by anesthesiologists (CZE 20.2%, SVK 20.5%) terminated in cesarean section. ConclusionsAlthough labor analgesia was available in all Czech and Slovak obstetric centers, only a small proportion of parturients received an effective method of labor pain relief (regional or intravenous analgesia).

Analysis of Physiological Respiratory Variable Alarm Alerts Among Laboring Women Receiving Remifentanil

(Anesth Analg. 2017;124(4):1211–1218) Remifentanil is a short-acting opioid. Its use for labor analgesia is controversial because of reports of associated apnea. The aim of this study was to perform a secondary analysis of respiratory data from a previous study of laboring women using patient-controlled intravenous (IV) remifentanil analgesia, in order to evaluate physiologic variables as early warning alerts of apnea.

Postoperative pain scores and opioid consumption in opioid-dependent patients with cancer after intraoperative remifentanil analgesia: A prospective case-controlled study.

Opioid dependency is becoming increasingly common among surgical patients with cancer, and can lead to inadequate pain relief during the initial postoperative period. No guidelines are currently available for the management of perioperative and postoperative morphine administration in these patients. As a first approach, the authors assessed the opioid requirements of these patients during the early postoperative period. A group of 35 consecutive surgical patients with cancer on opioid therapy (opioid-dependent group) for cancer pain were compared to a matched group of 44 surgical opioid-naive patients (control group). All patients underwent major head and neck or abdominal surgery. The following parameters were recorded and compared: preoperative and postoperative morphine consumption, patient-controlled analgesia records and Visual Analog Scale scores, intraoperative remifentanil and desflurane consumption, Bispectral Index monitoring values, heart rate, and blood pressure. Remifentanil requirements were significantly higher (1.4-fold) in the opioid-dependent group compared to the control group (p < 0.05). On postoperative day 1, morphine requirements were significantly higher in the opioid-dependent group (2.3-fold) compared to the control group (p < 0.05). Baseline heart rate was significantly higher in the opioid-dependent group and this difference remained significant during surgery, no significant difference in blood pressure was observed between the two groups. This study shows a 40 percent increase of intraoperative remifentanil requirements in opioid-dependent patients during cancer surgery. Morphine requirements during the postoperative period were increased by up to 140 percent.

THE EFFECTS OF SEVOFLURANE AND PROPOFOL ON ACOUSTIC RHINOMETRIC MEASUREMENTS

ABSTRACT Objective: The aim of the study was to compare nasal mucosal vasodilation induced by two different anesthetic used to provide controlled hypotension with the aid of acoustic rhinometry (AR). Methods: This study is prospective randomized clinical study. Fifty patients were randomized into propofol (Group P; n=25) and sevoflurane (Group S; n=25) groups. During anesthesia induction, Group P received propofol (2 mg kg -1 IV) and Group S was administered sevoflurane at a minimal alveolar concentration of 6-8%. Anesthesia was maintained with propofol (4 mg kg h -1 ) in Group P and 2% sevoflurane in Group S. Both groups received the analgesic remifentanil at a dose of 0.025 µg kg min -1 . Patients were performed nasal acoustic rhinometry (AR) measurements. Anesthetic doses were adjusted so as to ensure intraoperative hypotension by maintaining mean arterial pressure at 20-25% lower than the baseline value. Results: In both groups, a significant difference was detected between AR and nasal minimal cross-sectional areas (MCA) measurements taken from the patients in the supine position, both during the preoperative period and at 30 minutes after the induction of anesthesia, but a meaningful decrease in MCA1 and MCA2 values after the induction of anesthesia was observed for both groups. In addition, differences in measurements taken before and after the induction of anesthesia were greater in amplitude for the sevoflurane group versus the propofol group. Conclusion: Controlled hypotension induced using sevoflurane anesthesia might result in higher degrees of vasodilation relative to propofol anesthesia. Keywords: acoustic rhinometry, vasodilation, sevoflurane, propofol, controlled hypotension.

Remifentanil analgesia during external cephalic version for breech presentation in nulliparous women at term: A randomized controlled trial.

Background:The aim of the study was to assess the efficacy and safety of remifentanil for pain relief during external cephalic version (ECV) for breech presentation in nulliparous women at term.Methods:A total of 144 nulliparous women with singleton breech presentation were randomly divided into the intervention group and the placebo group, with 72 subjects in each group. The subjects in the intervention group received remifentanil (infused at 0.1 μg kg–1 min–1 with demand boluses of 0.1 μg/kg), whereas those in the placebo group were given saline placebo. This study was conducted from May 2013 to April 2016. The outcomes measures include pain (measured with the visual analog scale, VAS), success rate of ECV, maternal satisfaction for ECV, and adverse events.Results:A total of 137 participants completed the study. The intervention with remifentanil showed greater efficacy than did placebo in decreasing the VAS score immediately after ECV (intervention group 4.3 ± 2.2 vs placebo group 6.4 ± 2.5, P < 0.01). A significant difference in the ECV success rate was also found between the 2 groups (intervention group 56.9% vs placebo group 38.9%, P = 0.03). In addition, a significant difference in the satisfaction score was also detected (intervention group 9.3 ± 0.9 vs placebo group 6.7 ± 1.2, P < 0.01). The observed adverse events were similar between the 2 groups.Conclusion:This study shows that remifentanil could decrease pain, improve the ECV success rate, and improve satisfaction in nulliparous women at term during the period of ECV. Furthermore, it is also well tolerated with few adverse events.

Bedside Diode Laser Photocoagulation Under Remifentanil Analgesia for Retinopathy of Prematurity: Early Structural Outcomes.

Objectives:To evaluate one-year structural outcomes of bedside diode laser photocoagulation with remifentanil analgesia for retinopathy of prematurity (ROP) and discuss clinical and demographic characteristics of infants and other possible risk factors that may affect the outcome.Materials and Methods:The medical records of premature infants who were treated with bedside transpupillary diode laser photocoagulation under remifentanil analgesia for ROP were evaluated for clinical and demographic characteristics, accompanying systemic risk factors, laser parameters, complications of treatment, retreatment rate and one-year structural outcomes.Results:One-hundred and ninety-five eyes of 99 infants (59 males, 40 females) were recruited for the study. The mean gestational age and birth weight were 27.4±2.3 weeks (23-34) and 1003.3±297.8 g (570-2250), respectively. Laser therapy was performed for high-risk prethreshold ROP in 66.2% of eyes, aggressive posterior ROP (APROP) in 15.4% and threshold ROP in 18.4%. The mean number of laser spots was 1510.4±842.1 per laser session. No adverse effects of laser photocoagulation were observed except small lens opacities in two eyes and corneal opacity in one eye. Retreatment was needed in only three eyes, and vitreoretinal surgery was needed in six eyes of six patients despite laser treatment. Anatomic outcome was favorable in 189 eyes (96.9%) at the end of a 1-year follow-up. Presence of dilated and tortuous iris vessels (p=0.002) and tunica vasculosa lentis (p=0.009) along with type of ROP (APROP and stage 4a ROP at initial presentation) (p=0.001) were associated with poor anatomical outcome.Conclusion:Accurate and timely bedside transpupillary diode-laser photocoagulation under remifentanil analgesia is an effective and safe treatment modality for ROP, and may prevent vision-threatening retinal detachment and reduce the need for vitreoretinal surgery.