Intra-operative analgesia with remifentanil vs. dexmedetomidine: a systematic review and meta-analysis with trial sequential analysis

Intra-operative remifentanil is associated with increased postoperative analgesic requirements and opioid consumption. Dexmedetomidine has characteristics suggesting it may substitute for intra-operative remifentanil during general anaesthesia, but existing literature has reported conflicting results. We undertook this meta-analysis to investigate whether general anaesthesia including dexmedetomidine would result in less postoperative pain than general anaesthesia including remifentanil. The MEDLINE and PubMed electronic databases were searched up to October 2018. Only randomised trials including patients receiving general anaesthesia and comparing dexmedetomidine with remifentanil administration were included. Meta-analyses were performed mostly employing a random effects model. The primary outcome was pain score at rest (visual analogue scale, 0-10) at two postoperative hours. The secondary outcomes included: pain score at rest at 24 postoperative hours; opioid consumption at 2 and 24 postoperative hours; and rates of hypotension, bradycardia, shivering and postoperative nausea and vomiting. Twenty-one randomised trials, including 1309 patients, were identified. Pain scores at rest at two postoperative hours were lower in the dexmedetomidine group, with a mean difference (95%CI) of -0.7 (-1.2 to -0.2), I2  = 85%, p = 0.004, and a moderate quality of evidence. Secondary pain outcomes were also significantly better in the dexmedetomidine group. Rates of hypotension, shivering and postoperative nausea and vomiting were at least twice as frequent in patients who received remifentanil. Time to analgesia request was longer, and use of postoperative morphine and rescue analgesia were less, with dexmedetomidine, whereas episodes of bradycardia were similar between groups. There is moderate evidence that intra-operative dexmedetomidine during general anaesthesia improves pain outcomes during the first 24 postoperative hours, when compared with remifentanil, with fewer side effects.

Opioid-free anesthesia compared to opioid anesthesia for lung cancer patients undergoing video-assisted thoracoscopic surgery: A randomized controlled study

BACKGROUND

Reducing intra-operative opioid consumption benefits patients by decreasing postoperative opioid-related adverse events. We assessed whether opioid-free anesthesia would provide effective analgesia-antinociception monitored by analgesia index in video-assisted thoracoscopic surgery.

METHODS

Patients (ASA Ⅰ-Ⅱ, 18-65 years old, BMI <30 kg m-2) scheduled to undergo video-assisted thoracoscopic surgery under general anesthesia were randomly allocated into two groups to receive opioid-free anesthesia (group OFA) with dexmedetomidine, sevoflurane plus thoracic paravertebral blockade or opioid-based anesthesia (group OA) with remifentanil, sevoflurane, and thoracic paravertebral blockade. The primary outcome variable was pain intensity during the operation, assessed by the depth of analgesia using the pain threshold index with the multifunction combination monitor HXD‑I. Secondary outcomes included depth of sedation monitoring by wavelet index and blood glucose concentration achieved from blood gas.

RESULTS

One hundred patients were randomized; 3 patients were excluded due to discontinued intervention and 97 included in the final analysis. Intraoperative pain threshold index readings were not significantly different between group OFA and group OA from arriving operation room to extubation (P = 0.86), while the brain wavelet index readings in group OFA were notably lower than those in group OA from before general anesthesia induction to recovery of double lungs ventilation (P <0.001). After beginning of operation, the blood glucose levels in group OFA increased compared with baseline blood glucose values (P < 0.001). The recovery time and extubation time in group OFA were significantly longer than those in group OA (P <0.007).

CONCLUSIONS

This study suggested that our OFA regimen achieved equally effective intraoperative pain threshold index compared to OA in video-assisted thoracoscopic surgery. Depth of sedation was significantly deeper and blood glucose levels were higher with OFA. Study's limitations and strict inclusion criteria may limit the external validity of the study, suggesting the need of further randomized trials on the topic. Trial registration: ChiCTR1800019479, Title: "Opioid-free anesthesia in video-assisted thoracoscopic surgery lobectomy".

Effect of Remifentanil vs Neuromuscular Blockers During Rapid Sequence Intubation on Successful Intubation Without Major Complications Among Patients at Risk of Aspiration: A Randomized Clinical Trial

IMPORTANCE

It is uncertain whether a rapid-onset opioid is noninferior to a rapid-onset neuromuscular blocker during rapid sequence intubation when used in conjunction with a hypnotic agent.

OBJECTIVE

To determine whether remifentanil is noninferior to rapid-onset neuromuscular blockers for rapid sequence intubation.

DESIGN, SETTING, AND PARTICIPANTS

Multicenter, randomized, open-label, noninferiority trial among 1150 adults at risk of aspiration (fasting for <6 hours, bowel occlusion, recent trauma, or severe gastroesophageal reflux) who underwent tracheal intubation in the operating room at 15 hospitals in France from October 2019 to April 2021. Follow-up was completed on May 15, 2021.

INTERVENTIONS

Patients were randomized to receive neuromuscular blockers (1 mg/kg of succinylcholine or rocuronium; n = 575) or remifentanil (3 to 4 μg/kg; n = 575) immediately after injection of a hypnotic.

MAIN OUTCOMES AND MEASURES

The primary outcome was assessed in all randomized patients (as-randomized population) and in all eligible patients who received assigned treatment (per-protocol population). The primary outcome was successful tracheal intubation on the first attempt without major complications, defined as lung aspiration of digestive content, oxygen desaturation, major hemodynamic instability, sustained arrhythmia, cardiac arrest, and severe anaphylactic reaction. The prespecified noninferiority margin was 7.0%.

RESULTS

Among 1150 randomized patients (mean age, 50.7 [SD, 17.4] years; 573 [50%] women), 1130 (98.3%) completed the trial. In the as-randomized population, tracheal intubation on the first attempt without major complications occurred in 374 of 575 patients (66.1%) in the remifentanil group and 408 of 575 (71.6%) in the neuromuscular blocker group (between-group difference adjusted for randomization strata and center, -6.1%; 95% CI, -11.6% to -0.5%; P = .37 for noninferiority), demonstrating inferiority. In the per-protocol population, 374 of 565 patients (66.2%) in the remifentanil group and 403 of 565 (71.3%) in the neuromuscular blocker group had successful intubation without major complications (adjusted difference, -5.7%; 2-sided 95% CI, -11.3% to -0.1%; P = .32 for noninferiority). An adverse event of hemodynamic instability was recorded in 19 of 575 patients (3.3%) with remifentanil and 3 of 575 (0.5%) with neuromuscular blockers (adjusted difference, 2.8%; 95% CI, 1.2%-4.4%).

CONCLUSIONS AND RELEVANCE

Among adults at risk of aspiration during rapid sequence intubation in the operating room, remifentanil, compared with neuromuscular blockers, did not meet the criterion for noninferiority with regard to successful intubation on first attempt without major complications. Although remifentanil was statistically inferior to neuromuscular blockers, the wide confidence interval around the effect estimate remains compatible with noninferiority and limits conclusions about the clinical relevance of the difference.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03960801.

Opioids for newborn infants receiving mechanical ventilation

BACKGROUND

Mechanical ventilation is a potentially painful and discomforting intervention that is widely used in neonatal intensive care. Newborn infants demonstrate increased sensitivity to pain, which may affect clinical and neurodevelopmental outcomes. The use of drugs that reduce pain might be important in improving survival and neurodevelopmental outcomes.

OBJECTIVES

To determine the benefits and harms of opioid analgesics for neonates (term or preterm) receiving mechanical ventilation compared to placebo or no drug, other opioids, or other analgesics or sedatives.

SEARCH METHODS

We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL; 2020, Issue 9), in the Cochrane Library; MEDLINE via PubMed (1966 to 29 September 2020); Embase (1980 to 29 September 2020); and the Cumulative Index to Nursing and Allied Health Literature (CINAHL) (1982 to 29 September 2020). We searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials.

SELECTION CRITERIA

We included randomised and quasi-randomised controlled trials comparing opioids to placebo or no drug, to other opioids, or to other analgesics or sedatives in newborn infants on mechanical ventilation. We excluded cross-over trials. We included term (≥ 37 weeks' gestational age) and preterm (< 37 weeks' gestational age) newborn infants on mechanical ventilation. We included any duration of drug treatment and any dosage given continuously or as bolus; we excluded studies that gave opioids to ventilated infants for procedures.

DATA COLLECTION AND ANALYSIS

For each of the included trials, we independently extracted data (e.g. number of participants, birth weight, gestational age, types of opioids) using Cochrane Effective Practice and Organisation of Care Group (EPOC) criteria and assessed the risk of bias (e.g. adequacy of randomisation, blinding, completeness of follow-up). We evaluated treatment effects using a fixed-effect model with risk ratio (RR) for categorical data and mean difference (MD) for continuous data. We used the GRADE approach to assess the certainty of evidence.

MAIN RESULTS

We included 23 studies (enrolling 2023 infants) published between 1992 and 2019. Fifteen studies (1632 infants) compared the use of morphine or fentanyl versus placebo or no intervention. Four studies included both term and preterm infants, and one study only term infants; all other studies included only preterm infants, with five studies including only very preterm infants. We are uncertain whether opioids have an effect on the Premature Infant Pain Profile (PIPP) Scale in the first 12 hours after infusion (MD -5.74, 95% confidence interval (CI) -6.88 to -4.59; 50 participants, 2 studies) and between 12 and 48 hours after infusion (MD -0.98, 95% CI -1.35 to -0.61; 963 participants, 3 studies) because of limitations in study design, high heterogeneity (inconsistency), and imprecision of estimates (very low-certainty evidence - GRADE). The use of morphine or fentanyl probably has little or no effect in reducing duration of mechanical ventilation (MD 0.23 days, 95% CI -0.38 to 0.83; 1259 participants, 7 studies; moderate-certainty evidence because of unclear risk of bias in most studies) and neonatal mortality (RR 1.12, 95% CI 0.80 to 1.55; 1189 participants, 5 studies; moderate-certainty evidence because of imprecision of estimates). We are uncertain whether opioids have an effect on neurodevelopmental outcomes at 18 to 24 months (RR 2.00, 95% CI 0.39 to 10.29; 78 participants, 1 study; very low-certainty evidence because of serious imprecision of the estimates and indirectness). Limited data were available for the other comparisons (i.e. two studies (54 infants) on morphine versus midazolam, three (222 infants) on morphine versus fentanyl, and one each on morphine versus diamorphine (88 infants), morphine versus remifentanil (20 infants), fentanyl versus sufentanil (20 infants), and fentanyl versus remifentanil (24 infants)). For these comparisons, no meta-analysis was conducted because outcomes were reported by one study.

AUTHORS' CONCLUSIONS

We are uncertain whether opioids have an effect on pain and neurodevelopmental outcomes at 18 to 24 months; the use of morphine or fentanyl probably has little or no effect in reducing the duration of mechanical ventilation and neonatal mortality. Data on the other comparisons planned in this review (opioids versus analgesics; opioids versus other opioids) are extremely limited and do not allow any conclusions. In the absence of firm evidence to support a routine policy, opioids should be used selectively - based on clinical judgement and evaluation of pain indicators - although pain measurement in newborns has limitations.

Anesthetic Management of Awake Craniotomy for Resection of the Language and Motor Cortex Vascular Malformations

BACKGROUND

Although the safety and feasibility of awake craniotomy are well established for epilepsy and brain tumor surgery, its application for resection of vascular lesions, including arteriovenous malformations (AVMs) and cavernomas, is still limited. Apart from the usual challenges of awake craniotomy, vascular lesions pose several additional problems. Our goal is to determine the safety and practicality of awake craniotomy in patients with cerebral vascular malformations located near the eloquent areas, using a refined anesthetic protocol.

METHODS

A retrospective case series was performed on 7 patients who underwent awake craniotomy for resection of AVMs or cavernomas located in the eloquent language and motor areas. Our protocol consisted of achieving deep sedation, without a definitive airway, using a combination of propofol, dexmedetomidine, and remifentanil/fentanyl during scalp block placement and surgical exposure, then transitioning to a wakeful state during the resection.

RESULTS

Six patients had intracranial AVMs, and 1 patient had a cavernoma. Six patients had complete resection; however, 1 patient underwent repeat awake craniotomy for residual AVM nidus. The patients tolerated the resection under continuous awake neurologic and neurophysiologic testing without significant perioperative complications or the need to convert to general anesthesia with a definitive airway.

CONCLUSIONS

Awake craniotomy for excision of intracranial vascular malformations located near the eloquent areas, in carefully selected patients, can facilitate resection by allowing close neuromonitoring and direct functional assessment. A balanced combination of sedative and analgesic medications can provide both adequate sedation and rapid wakeup, facilitating the necessary patient interaction and tolerance of the procedure.

Effect of ancillary drugs on sevoflurane related emergence agitation in children undergoing ophthalmic surgery: a Bayesian network meta-analysis

BACKGROUND

The comparative efficacy of ancillary drugs on sevoflurane related emergence agitation (EA) in children undergoing ophthalmic surgery remains controversial.

METHODS

The databases were retrieved in an orderly manner from the dates of their establishment to October, 2018, including PubMed, The Cochrane Library and Web of Science, to collect randomized controlled trials (RCT) of different anesthetic drugs combined with sevoflurane for ophthalmic surgery. Then a network meta-analysis was conducted using R and Stata 12.0 softwares.

RESULTS

The meta-analysis showed that, in reducing sevoflurane related EA, dexmedetomidine, ketamine, propofol, fentanyl, midazolam, sufentanil, remifentanil and clonidine were superior to placebo (P < 0.05). The network meta-analysis showed that the effects of ancillary drugs combine with sevoflurane in reducing risk of EA in children undergoing ophthalmic surgery was superior to placebo: dexmedetomidine (OR = 0.17, 95% CrI 0.12-0.22), ketamine (OR = 0.30, 95% CrI 0.11-0.49), propofol (OR = 0.24, 95% CrI 0.09-0.63), fentanyl (OR = 0.16, 95% CrI 0.08-0.56), midazolam (OR = 0.20, 95% CrI 0.09-0.40), sufentanil (OR = 0.27, 95% CrI 0.14-0.41), remifentanil (OR = 0.18, 95% CrI 0.08-0.54) and clonidine (OR = 0.14, 95% CrI 0.07-0.41). The SUCRA of placebo, dexmedetomidine, ketamine, propofol, fentanyl, midazolam, sufentanil, remifentanil, clonidine were respectively 0.26, 77.93, 27.71, 42.8, 69.43, 52.89, 59.83, 57.62 and 61.53%.

CONCLUSIONS

The effects of dexmedetomidine combine with sevoflurane in reducing risk of emergence agitation in children undergoing ophthalmic surgery was superior to other drugs.

Population pharmacokinetics of remifentanil in critically ill patients receiving extracorporeal membrane oxygenation

Extracorporeal membrane oxygenation (ECMO) is associated with pharmacokinetic (PK) changes of drugs. It presents considerable challenges to providing optimal dosing regimens for patients receiving ECMO. We aimed to describe the population PK of remifentanil in critically ill adult patients receiving venoartrial extracorporeal membrane oxygenation (VA-ECMO) and to identify determinants associated with altered remifentanil concentrations. The population PK model of remifentanil was developed using nonlinear mixed effects modelling (NONMEM). Fifteen adult patients who received a continuous infusion of remifentanil during VA-ECMO participated in the study. The PK of remifentanil was best described by a one-compartment model with additive and proportional residual errors. Remifentanil concentrations were affected by sex and ECMO pump speed. The final PK model included the effect of sex and ECMO pump speed on clearance is developed as followed: clearance (L/h) = 366 × 0.502sex × (ECMO pump speed/2350)2.04 and volume (L) = 41. Remifentanil volume and clearance were increased in adult patients on VA-ECMO compared with previously reported patients not on ECMO. We suggest that clinicians should consider an increased remifentanil dosing to achieve the desired level of sedation and provide a dosing regimen according to sex and ECMO pump speed.

Comparison between multimodal and intraoperative opioid free anesthesia for laparoscopic sleeve gastrectomy: a prospective, randomized study

Anesthesia for laparoscopic sleeve gastrectomy and perioperative management remains a challenge. Several clinical studies indicate that opioid-free anesthesia (OFA) may be beneficial, but there is no consensus on the most optimal anesthesia technique in clinical practice. The aim of our study was to assess the potential benefits and risks of intraoperative OFA compared to multimodal analgesia (MMA) with remifentanil infusion. In a prospective, randomized study, we analyzed 59 patients' data. Primary outcome measures were oxycodone consumption and reported pain scores (numerical rating scale, NRS) at 1, 6, 12, and 24th hours after surgery. Postoperative sedation on the Ramsay scale, nausea and vomiting on the PONV impact scale, desaturation episodes, pruritus, hemodynamic parameters, and hospital stay duration were also documented and compared. There were no significant differences in NRS scores or total 24-h oxycodone requirements. In the first postoperative hour, OFA group patients needed an average of 4.6 mg of oxycodone while the MMA group 7.72 mg (p = 0.008, p < 0.05 statistically significant). The PONV impact scale was significantly lower in the OFA group only in the first hour after the operation (p = 0.006). Patients in the OFA group required higher doses of ephedrine 23.67 versus 15.69 mg (p = 0.039) and more intravenous fluids 1160 versus 925.86 ml (p = 0.007). The mode of anesthesia did not affect the pain scores or the total dose of oxycodone in the first 24 postoperative hours. Only in the first postoperative hour were an opioid-sparing effect and reduction of PONV incidence seen in the OFA group when compared with remifentanil-based anesthesia. However, patients in the OFA group showed significantly greater hemodynamic lability necessitating higher vasopressor doses and more fluid volume.

Efficacy and safety of sevoflurane vs propofol in combination with remifentanil for anesthesia maintenance during craniotomy: A meta-analysis

BACKGROUND

The purpose of this study was to evaluate the efficacy and safety of sevoflurane-remifentanil (SR) vs propofol-remifentanil (PR) as inhalation anesthesia or total intravenous anesthesia in patients undergoing craniotomy, respectively.

METHODS

Electronic databases included PubMed, ScienceDirect, Embase, Cochrane library, CNKI, and Wanfang data were searched using suitable search items. Randomized clinical controlled trials comparing the combination of SR and PR as anesthetics for neurosurgery were included. The outcomes included wake-up time, spontaneous respiration time, extubation time, and safety.

RESULTS

Seventeen studies were included in this meta-analysis. There were no statistically significant differences in wake-up time (P = .25, standardized mean difference (SMD) = 0.29, 95% CI -0.20 to 0.77), extubation time (P = .1, SMD = 0.52, 95% CI -0.11 to 1.14) and spontaneous respiration time (P = .58, SMD = 0.43, 95% CI -1.07 to 1.93) when patients with SF and PF for anesthesia maintenance. Moreover, the changes of hemodynamic parameters are similar between the 2 groups. During anesthesia maintenance, SF could significantly increase the incidence of hypotension and brain edema than PF (P = .02, SMD = 1.68, 95% CI 1.07 to 2.62; P < .0001, SMD = 3.37, 95% CI 1.86 to 6.12), PF markedly promoted the incidence of hypertension (P = .001, SMD = 0.55, 95% CI 0.39 to 0.79). The postoperative adverse reactions were similar between the 2 groups (P > .05), but the incidence of postoperative nausea and vomiting proved to be higher in SF group (P < .0001, SMD = 2.12, 95% CI 1.47 to 3.07).

CONCLUSIONS

SR and PR as anesthetics in patients underwent craniotomy had similar effects, but PR was superior to SR in terms of safety of intraoperation and postoperation.

Evaluation of the effects of dexmedetomidine and remifentanil on pain with the analgesia nociception index in the perioperative period in hysteroscopies under general anesthesia. A randomized prospective study

Objectives To compare analgesia nociception index (ANI) values, visual analog scale (VAS) values, and hemodynamic parameters in hysteroscopy patients who received remifentanil and dexmedetomidine during general anesthesia. Methods: In total, 30 patients who underwent hysteroscopy between March and September 2016 at the University of Health Sciences Fatih Sultan Mehmet Health Research and Application Center, Ankara, Turkey were included in this prospective study. Standard hemodynamic monitoring, ANI, and bispectral index (BIS) monitoring were applied to the patients. At 10 min prior to induction, 1 μg/kg of remifentanil was applied in Group R (n=15) and 1 μg/kg of dexmedetomidine was applied in Group D (n=15). After induction, sevoflurane was used for maintenance with dexmedetomidine at 0.2-0.7 μg/kg/hour in Group D and remifentanil at 0.05-0.5 μg/kg/minute in Group R. Perioperative and postoperative analgesia levels (ANI and VAS, respectively), hemodynamics, and complications were recorded. Results: Even though the ANI levels in Group D were lower at the perioperative 5th and 10th minutes, the ANI values were between the targeted limits, except for the measurement after I-gel insertion, in both groups. Hemodynamic parameters were within normal limits, but the mean arterial pressures in Group R after induction, following I-gel placement, and at the perioperative 5th, 10th, and 20th minutes were lower and at postoperative 30th minute were significantly higher.   Conclusion: Dexmedetomidine and remifentanil are both efficacious agents for perioperative analgesia in hysteroscopy cases.

A systematic review and meta-analysis of the safety and efficacy of remifentanil and dexmedetomidine for awake fiberoptic endoscope intubation

BACKGROUND

Awake fiberoptic endoscope intubation (AFOI) is the primary strategy for managing anticipated difficult airways. Adequate sedation, most commonly being achieved with remifentanil and dexmedetomidine, is integral to this procedure. This meta-analysis aimed to compare the safety and efficacy of these 2 sedatives.

METHODS

We conducted electronic searches in Embase, Web of Science, PubMed, Google Scholar, Medline, Springer, and Web of Science with no language restrictions. Studies comparing safety and efficacy between the sole use of remifentanil and dexmedetomidine among patients who underwent AFOI were included. Eight randomized controlled trials, comprising 412 patients, met the inclusion criteria. The primary outcomes were first attempt intubation success rate and incidence of hypoxia. The secondary outcomes were the Ramsay Sedation Scale score at intubation, memory recall of endoscopy, and unstable hemodynamic parameters during intubation.

RESULTS

Dexmedetomidine significantly reduced the incidence of hypoxemia during AFOI (risk ratio: 2.47; 95% confidence [CI]: 1.32-4.64]) compared with remifentanil; however, the first intubation success rates were equivalent (risk ratio: 1.12; 95% CI: 0.87-1.46]. No significant differences between the 2 sedatives were found for the Ramsay Sedation Scale score at intubation (mean difference: -0.14; 95% CI: -0.66-0.38) or unstable hemodynamic parameters during intubation (risk ratio: 0.83; 95% CI: 0.59-1.17). Dexmedetomidine reduced memory recall of endoscopy (risk ratio: 1.39; 95% CI: 1.13-1.72).

CONCLUSIONS

While both remifentanil and dexmedetomidine are effective for AFOI and well-tolerated, dexmedetomidine may be more effective in reducing the incidence of hypoxemia and memory recall of endoscopy.

PROSPERP REGISTRATION NUMBER

CRD42020169612.

Remifentanil protects against myocardial ischemia/reperfusion injury via miR-205-mediated regulation of PINK1

Myocardial ischemia/reperfusion (I/R) injury could lead to severe cardiovascular ischemic disease, including myocardial infarction and contractile dysfunction. Remifentanil demonstrated protective effect on myocardial I/R injury. The underlying pathophysiological mechanism was then investigated in this study. In the current study, primary cardiomyocytes were isolated from rats, and then preconditioned with remifentanil. Rats, tail vein injected with miR-205 antagomir, were subjected to infusion of remifentanil, and then subjected to regional ischemia followed by reperfusion. The results demonstrated that cell viability of hypoxia/reoxygenation-induced cardiomyocytes was increased post remifentanil, while the apoptosis was decreased accompanied with reduced cleaved caspase-3 expression. Hypoxia/reoxygenation treatment increased miR-205 and decreased PINK1 (PTEN induced putative kinase 1) expression. However, preconditioning with remifentanil reduced miR-205 and enhanced PINK1. Moreover, over-expression of miR-205 decreased PINK1 expression and counteracted the effects of remifentanil-induced increase of cell viability and decrease of cell apoptosis in hypoxia/reoxygenation-induced cardiomyocytes. Injection with miR-205 antagomir improved remifentanil-induced decrease of infarct size and LDH (lactic acid dehydrogenase) activity in rat model with I/R injury. In conclusion, miR-205 might participate in the protective effect of remifentanil in rat myocardial I/R injury via regulation of PINK1, providing a potential target for amelioration of cardiovascular ischemic disease.

Comparison of the effects of dexmedetomidine and remifentanil on perioperative hemodynamics and recovery profile of patients undergoing laryngeal microsurgery: A prospective randomized double-blinded study

BACKGROUND

Laryngeal microsurgery (LMS) causes hemodynamic instability and postoperative agitation, cough, pain, nausea, and vomiting. Moreover, because of a short operation time, it is associated with challenging anesthetic management. The aim of this study was to compare the usefulness of continuous administration of dexmedetomidine and remifentanil in inducing general anesthesia in patients undergoing LMS.

METHODS

This is a prospective randomized control design. Continuous intravenous infusion of dexmedetomidine (group D) or remifentanil (group R) was administered from 10 minutes before the induction of anesthesia to the end of surgery. In both groups, 1.5 mg/kg propofol and 0.5 mg/kg rocuronium were administered for the induction of anesthesia, and desflurane were titrated during the measurement of the bispectral index. We recorded hemodynamic data, recovery time, grade of cough, pain score, and analgesic requirements during the perioperative period.

RESULTS

61 patients were finally analyzed (30 for group D, 31 for group R). The incidence of moderate to severe postoperative sore throat was higher in group R than in group D (42% vs 10%, P = .008), and the quantity of rescue fentanyl used in post-anesthesia care unit was significantly higher in group R than in group D (23.2 ± 24.7 mg vs 3.3 ± 8.6 mg; P < .001); however, the time required for eye opening was significantly longer in group D than in group R (599.4 ± 177.9 seconds vs 493.5 ± 103.6 seconds; P = .006). The proportion of patients with no cough or single cough during extubation was comparable between the 2 groups (group D vs group R: 73% vs 70%) as was the incidence of hemodynamic instability.

CONCLUSION

Although there was a transient delay in emergence time, dexmedetomidine reduced postoperative opioid use and the incidence of sore throat. Dexmedetomidine may be used as an alternative agent to opioids in patients undergoing LMS.

Comparison between total intravenous anesthesia and balanced anesthesia on postoperative opioid consumption in patients who underwent laparoscopic-assisted distal gastrectomy

Remifentanil is the most frequently prescribed opioid for total intravenous anesthesia (TIVA) or balanced anesthesia (BA), due to its favorable pharmacological properties. However, several studies have reported opioid-induced hyperalgesia and/or acute tolerance after intraoperatively using remifentanil. In addition, it is imperative to control postoperative pain with lower doses of opioid anesthetic agents. Therefore, we compared the amount of opioid consumption between TIVA with propofol-remifentanil and BA with desflurane-remifentanil, to control postoperative pain in patients who underwent laparoscopic-assisted distal gastrectomy (LADG) with gastroduodenostomy.We retrospectively evaluated demographic variables (age, gender, height, weight, and smoking habits), the duration of general anesthesia (GA), and intraoperatively administered remifentanil consumption through the electronic medical records of patients who underwent LADG with gastroduodenostomy due to early stomach cancer. The primary outcome was postoperative opioid consumption during postoperative day (POD) 2. The secondary outcomes were the incidence of any rescue opioid analgesics administered, numeric rating scale, and various adverse effects during POD 2. We categorized the data in 2 patient groups to compare TIVA with propofol-remifentanil (TIVA group) to BA with desflurane-remifentanil (BA group) on the postoperative opioid analgesic consumption.We divided 114 patients into the TIVA (46 patients) and BA (68 patients) groups. Opioid consumption as a primary outcome was significantly higher in the BA group than in the TIVA group during POD 2 except in the post-anesthesia care unit. The cumulative opioid consumption was significantly higher in the BA than in the TIVA group. The incidence of rescue analgesic at POD 2 was higher in the BA than in the TIVA group. In the TIVA group, remifentanil consumption was higher, and the duration of GA was shorter than that in the BA group. No statistically significant differences were observed when comparing other variables.Our results indicated that the maintenance of GA with TIVA (propofol-remifentanil) reduces opioid consumption for postoperative pain control compared to BA (desflurane-remifentanil) in patients undergoing LADG with gastroduodenostomy.

Postoperative Drip-Infusion of Remifentanil Reduces Postoperative Pain-A Retrospective Observative Study

Development of remifentanil-induced hyperalgesia (RIH) postoperatively is an unpleasant experience that requires further treatment. This study assessed the effects of gradual withdrawal combined with drip infusion of remifentanil on postoperative pain and the requirement for rescue analgesics. A total of 559 patients receiving total intravenous anesthesia with propofol and remifentanil were enrolled. All patients either underwent gradual withdrawal of remifentanil (GWR) or gradual withdrawal combined with drip infusion (GWDR) with a dose of 1 mcg·kg⁻¹ for 30 min after extubation. The numeric rating scale (NRS) and the requirement of rescue analgesics were assessed. The requirement for rescue analgesics was significantly lower in the GWDR group than in the GWR group (13.2% vs. 35.7%; p < 0.001). At the post-anesthetic care unit (PACU), patients in the GWDR group had a lower NRS pain score (p < 0.001). In addition, in the postoperative 2nd hour, patients in the GWDR group had a significantly lower NRS than the GWR group (beta, −0.31; p = 0.003). No remifentanil-related adverse effects were observed. We found that gradual withdrawal combined with drip infusion of remifentanil required less rescue analgesics and reduced pain scores. The new way of remifentanil administration may be effective to prevent RIH.

Comparison of Core Body Temperatures in Patients Administered Remimazolam or Propofol during Robotic-Assisted and Laparoscopic Radical Prostatectomy

Background and Objectives: Different types of anesthetics affect thermoregulatory mechanisms, such as the redistribution of body temperature, loss of skin heat, or inhibition of thermoregulatory vasoconstriction. Therefore, we compared remimazolam with propofol in terms of core body temperature in patients undergoing robotic-assisted and laparoscopic radical prostatectomy. Materials and methods: Ninety patients were randomly assigned to either the propofol−remifentanil (PR) group or the remimazolam−remifentanil (RR) group. The PR group (n = 45) received effect-site concentrations of 6.0 μg/mL of propofol and 4 ng/mL of remifentanil, followed by 0.9 mg/kg of 1% rocuronium and maintenance with effect-site concentrations of 2−4 μg/mL of propofol and 3 ng/mL of remifentanil. The RR group (n = 45) received remimazolam 6 mg/kg/h by continuous intravenous infusion and the effect-site concentration of 4 ng/mL of remifentanil, followed by 0.9 mg/kg of 1% rocuronium, remimazolam 1−3 mg/kg/h, and remifentanil 3 ng/mL. The primary outcome was core body temperature, and secondary outcomes included vasoconstriction threshold (°C) and time to onset of vasoconstriction (min). Results: The core body temperature in the RR group was significantly higher at 60, 80, 100, 120, 140, 160, and 180 min after induction than in the PR group (p < 0.01). The vasoconstriction threshold was significantly higher in the RR group (35.2 ± 0.4) than in the PR group (34.8 ± 0.3) (p < 0.01). The time to onset of vasoconstriction was significantly less in the RR group (150.5 ± 10.2) than in the PR group (158.5 ± 8.4) (p < 0.01). However, the incidence of intraoperative hypothermia was not significant between two groups. Conclusions: Remimazolam appears to reduce vasoconstriction threshold less than and had a faster onset of vasoconstriction, resulting in superior thermoregulatory control.

Abdominal Wall Block Decreases Intraoperative Opioid Con-Sumption by Surgical Pleth Index-Guided Remifentanil Administration in Single-Port Laparoscopic Herniorrhaphy: A Prospective Randomized Controlled Trial

Abdominal wall blocks (AWBs) can reduce pain during surgery and lessen opioid demand. Since it is difficult to know the exact level of intraoperative pain, it is not known how much the opioid dose should be reduced. In this study, using the surgical pleth index (SPI), which indicates pain index from sympathetic fibers, the amount of remifentanil consumption was investigated. We conducted single-port laparoscopic hernia repair in 64 patients, as follows: the regional block group (R group) was treated with AWB, while the control group (C group) was only subjected to general anesthesia. In both groups, the remifentanil concentration was adjusted to maintain the SPI score between 30 and 40 during surgery. The primary parameter was the amount of remifentanil. A total of 52 patients completed the study (24 in the R group, 28 in the C group). The remifentanil dose during surgery was decreased in the R group (29 ± 21 vs. 56 ± 36 ng/kg/min; p = 0.002). Visual analogue scale score and additional administrated analgesics were also low in the R group. As such, AWB can reduce the remifentanil dose while maintaining the same pain level.

The effect of dexmedetomidine and remifentanil on the postoperative sore throat after thyroidectomy

BACKGROUND

Postoperative sore throat (POST) is an important concern in surgical patients undergoing endotracheal intubation. Its prevalence after thyroidectomy is up to 80%. The current study aimed to assess the effect of dexmedetomidine and remifentanil on postoperative sore throat.

METHODS

Seventy-four patients who underwent thyroidectomy were randomized to receive either dexmedetomidine (group D) or remifentanil (group R). At anesthesia induction, group D received dexmedetomidine 1 μg/kg over 10 minutes, followed by continuous dexmedetomidine infusion at 0.3 to 0.6 μg/kg/hour during surgery. Group R received remifentanil of 3 to 4 ng/ml during induction, followed by 1.5 to 2.5 ng/ml remifentanil infusion during surgery. POST at rest and swallowing was assessed during the first 24 hours in serial time periods (0-1, 1-6, and 6-24 hours). Hoarseness and postoperative pain score were also assessed.

RESULTS

POST incidence at rest (0-1, 1-6, and 6-24 hours) and swallowing (1-6 and 6-24 hours) was lower in group D than in group R. POST severity was significantly lower in group D than in group R during each time period. The incidence of postoperative hoarseness was also lower in group D than in group R at 1 to 6 and 6 to 24 hours. The postoperative pain score was lower in group D than in group R during each time period.

CONCLUSION

Intraoperative dexmedetomidine infusion reduced the incidence and severity of POST for 24 hours after thyroidectomy.

Immediate extubation after heart transplantation in a child by remifentanil-based ultra-fast anesthesia: A case report

RATIONALE

Ventilator-associated complications comprise important fatal aetiologies during heart transplantation. Ultra-fast anesthesia might provide the most effective measure to prevent this type of complication. Immediate extubation after heart transplantation (IEAHT) has recently been reported in adult patients. However, IEAHT in children is much more challenging due to limitations in anesthesia protocols. Recently, we managed to perform an ultra-fast anesthesia protocol combined with IEAHT during a heart transplant operation in a child, who had an excellent postoperative outcome.

PATIENT CONCERNS

A 13-year-old girl had been diagnosed with dilated cardiomyopathy 5 years before this case, due to intractable dyspnoea and cough. She received multiple medical treatments after diagnosis, with minimal effects. Physical examination findings included a bulge in her left chest and pitting edema over both legs. Moist rales could be heard in the lung. Echocardiography revealed very large heart chambers, with an ejection fraction of 17%.

DIAGNOSIS

The patient was diagnosed with dilated cardiomyopathy and scheduled to undergo an emergent operation for heart transplantation.

INTERVENTIONS

The patient underwent an ultra-fast anesthesia protocol and ultra-fast reversal during heart transplantation. General anesthesia was induced with etomidate, fentanyl, and vecuronium; it was then maintained with remifentanil-based total intravenous anesthesia.

OUTCOMES

Immediately after the end of the operation, the patient was brought to consciousness with stable breathing and haemodynamics. The patient was successfully extubated on the operating table and transferred to the intensive care unit with spontaneous breathing, without postoperative mechanical ventilation. The recovery period was uneventful and the patient was discharged 1 month later without complications.

LESSONS

Our experience, in this case, revealed that IEAHT in children is achievable if the ultra-fast protocol is performed properly and carefully, in order to prevent ventilator-associated complications.

The impact of sufentanil versus remifentanil on surgical site wound healing in caesarean section primiparas undergoing epidural anaesthesia: A systematic meta-analysis

Caesarean section (C-section) is a prevalent obstetric surgical procedure, with the choice of analgesic agents playing a pivotal role in postoperative recovery. This systematic meta-analysis aimed to compare the effects of sufentanil (ST) and remifentanil (RT) on postoperative wound healing in caesarean section primiparas undergoing epidural anaesthesia. A comprehensive search was conducted across multiple databases, adhering to PRISMA guidelines, yielding eight randomized controlled trials (RCTs) for inclusion. The primary outcome was wound healing assessment using the REEDA (redness, edema, ecchymosis, discharge, approximation) scale on the third, fifth and tenth postoperative days. The meta-analysis encompassed 691 primiparas. A significant difference in wound healing was observed between ST and RT on the third (I2  = 99%; Random: SMD: 6.75, 95% CIs: 3.11-10.39, p < 0.01) and fifth days (I2  = 99%; Random: SMD: 3.63, 95% CIs: 1.56-5.70, p < 0.01) postcaesarean section. However, no significant difference was noted on the tenth day (I2  = 5%; Random: SMD: 0.00, 95% CIs: -0.45-0.45, p = 0.35). Sufentanil and remifentanil exhibit differential effects on early postoperative wound healing in caesarean section primiparas undergoing epidural anaesthesia. While both opioids are effective analgesics, sufentanil demonstrates a more pronounced impact on wound healing during the immediate postoperative days. Clinicians should consider these findings when selecting an opioid for pain management in this patient population.

Remifentanil protects against myocardial ischemia/reperfusion injury via miR-205-mediated regulation of PINK1

Myocardial ischemia/reperfusion (I/R) injury could lead to severe cardiovascular ischemic disease, including myocardial infarction and contractile dysfunction. Remifentanil demonstrated protective effect on myocardial I/R injury. The underlying pathophysiological mechanism was then investigated in this study. In the current study, primary cardiomyocytes were isolated from rats, and then preconditioned with remifentanil. Rats, tail vein injected with miR-205 antagomir, were subjected to infusion of remifentanil, and then subjected to regional ischemia followed by reperfusion. The results demonstrated that cell viability of hypoxia/reoxygenation-induced cardiomyocytes was increased post remifentanil, while the apoptosis was decreased accompanied with reduced cleaved caspase-3 expression. Hypoxia/reoxygenation treatment increased miR-205 and decreased PINK1 (PTEN induced putative kinase 1) expression. However, preconditioning with remifentanil reduced miR-205 and enhanced PINK1. Moreover, over-expression of miR-205 decreased PINK1 expression and counteracted the effects of remifentanil-induced increase of cell viability and decrease of cell apoptosis in hypoxia/reoxygenation-induced cardiomyocytes. Injection with miR-205 antagomir improved remifentanil-induced decrease of infarct size and LDH (lactic acid dehydrogenase) activity in rat model with I/R injury. In conclusion, miR-205 might participate in the protective effect of remifentanil in rat myocardial I/R injury via regulation of PINK1, providing a potential target for amelioration of cardiovascular ischemic disease.

Pharmacodynamic Analysis of the Influence of Propofol on Left Ventricular Long-Axis Systolic Performance in Cardiac Surgical Patients

BACKGROUND

Propofol induced a decline in the left ventricular (LV) systolic performance in non-cardiac surgery. We tested the hypothesis that propofol decreased the LV contractile function by dose dependent manner in cardiac surgery patients.

METHODS

Anesthesia was maintained with target-controlled infusions of propofol and remifentanil in cardiac surgery patients. With a fixed effect-site concentration (Ce) of remifentanil (20 ng/mL) after sternotomy, the Ce of propofol was adjusted to maintain a Bispectral index of 40-60 (Ce1). Mitral annular Doppler tissue image tracings and other echocardiographic variables, including end-diastolic and end-systolic volumes, stroke volume, and mitral inflow pulse wave Doppler profile at Ce1, were recorded using transesophageal echocardiography. Echocardiographic recordings were repeated after the Ce-values of propofol were doubled and tripled at 10-minute intervals (defined as Ce2 and Ce3, respectively). Serial changes in echocardiographic variables for each Ce of propofol were assessed using generalized linear mixed effect modeling. The pharmacodynamic relationship between the Ce of propofol and peak systolic mitral annular velocity (Sm) was analyzed by logistic regression using non-linear mixed effect modeling (NONMEM).

RESULTS

Means of Ce1, Ce2, and Ce3 were 0.8, 1.6, and 2.4 μg/mL, respectively, and their means of Sm (95% confidence interval) were 9.7 (9.3-10.2), 8.7 (8.2-9.1), and 7.5 cm/sec (7.0-8.0), respectively (P < 0.01). Ce values of propofol and Sm showed a significant inter-correlation and predictability (intercept, 10.8; slope-1.0 in generalized mixed linear modeling; P < 0.01). Ce values producing 10% and 20% decline of Sm with 50%-probability were 1.4 and 2.1 μ/mL, respectively.

CONCLUSION

Propofol reduces LV systolic long-axis performance in a dose-dependent manner.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01826149.

Inguinal hernia repair in day surgery: the role of MAC (Monitored Anesthesia Care) with remifentanil

BACKGROUND

The extension of indications for procedures in a Day Surgery (DS) setting has led to changes in the anesthetic and surgical treatment of Inguinal Hernias (IH). According to the recommendations of the European Hernia Society, the treatment of IH in DS units should be performed under Monitored Anesthesia Care (MAC).

PATIENTS AND METHODS

960 patients underwent IH repairs over a period of 24 months. The patients were randomly divided into two groups: R (remifentanil) and F (fentanyl); the group F was considered as a control group. The exclusion criteria in both group were: morbid obesity (BMI>40 or BMI>35 in association with high blood pressure or diabetes); coagulopathy; OSAS (obstructive sleep apnea syndrome) with AHI >10; cardiovascular, respiratory, renal, hepatic or metabolic disease; history of substances abuse; GERD-related esophagitis (gastro-esophageal reflux disease); chronic analgesic use; allergy to local anesthetic and ASA>III. Patients reported their level of pain on a verbal numeric scale (VNS), with scores ranging from 0 to 10. For each patient systolic and diastolic blood pressure (SBP and DBP), mean arterial pressure (MAP), heart rate (HR) and peripheral oxygen saturation (SpO2) were recorded. The results are presented as the mean value ± standard deviations; statistical analysis was performed using Student's t-test.

RESULTS

Amongst the 960 procedures, complications or side effects related to the anesthetic techniques didn't occur; no procedure-related complications requiring mechanical ventilation support were reported. Our research focused on evaluating remifentanil effectiveness in pain control and its impact on hemodynamic stability and respiratory function. There was a significant difference between the two groups with regard to the VNS.

CONCLUSIONS

Remifentanil, is an excellent drug for pain control during intra-operative procedures, that allows an optimal hemodynamic stability for IH repairs in a DS setting, due to its pharmacokinetic and pharmacodynamic properties and few adverse effects.

Neonatal effect of remifentanil in cesarean section with general anesthesia: A protocol of systematic review and meta-analysis

BACKGROUND

Although several previous studies have reported the efficacy of remifentanil in cesarean section (CS) under general anesthesia, no study has specifically addressed its neonatal effect (NE) in CS under general anesthesia systematically. Thus, this study will systematically investigate the NE of remifentanil in CS under general anesthesia.

METHODS

Electronic databases including MEDLINE, EMBASE, Cochrane Library, Web of Science, Chinese Biomedical Literature Database, and China National Knowledge Infrastructure will be systematically retrieved with the assistance of a specialist librarian to check randomized controlled trials reporting NE in CS under general anesthesia. We will retrieve all electronic databases from their initial time to March 20, 2020 without restrictions of language. All process of study selection, data extraction, and risk of bias evaluation will be carried out by 2 independent authors. We will invite another senior expert to solve the problems that arise between 2 authors. Data will be pooled and analyzed using RevMan V.5.3 software.

RESULTS

Outcomes consist of assessment of neonatal adaptation, requirements for postoperative respiratory support of neonates, systolic and diastolic noninvasive blood pressure, mean blood pressure, heart rate, electrocardiography, umbilical cord blood gas analysis, and adverse events.

CONCLUSION

This study will present evidence of the NE of remifentanil in CS under general anesthesia. This information may inform benefits of intervention to guide the usage of remifentanil in CS under general anesthesia.

STUDY REGISTRATION

INPLASY202040028.

Low-Dose Remifentanil in Preterm Cesarean Section with General Anesthesia: A Randomized Controlled Trial

BACKGROUND AND OBJECTIVE

The conventional technique of general anesthesia induction during a Cesarean section involves the use of opioids only after cord clamping. We hypothesized that the use of remifentanil before cord clamping might reduce the use of maternal supplemental anesthetic agents and improve the maternal hemodynamics status and neonatal adaptation of the preterm neonate.

METHODS

A phase III, double-blind, randomized, placebo-controlled, hospital-based trial enrolled parturients undergoing a Cesarean section under general anesthesia before 37 weeks of gestation. Block randomization allocated pregnant women to remifentanil or placebo. The primary outcome was the rate of newborns with Apgar scores < 7 at 5 min. Secondary outcomes were maternal hemodynamic parameters, complications of anesthetic induction, use of adjuvant anesthetic agents, neonatal respiratory distress, umbilical cord pH, and lactate levels.

RESULTS

A total of 52/55 participants were analyzed, comprising 27 women in the remifentanil group and 25 in the placebo group. Nine of 27 (33.3%) neonates had an Apgar score < 7 at 5 min in the remifentanil group versus 11/25 (44.0%) in the placebo group (p = 0.45, odds ratio = 0.66, 95 confidence interval 0.20-2.18). The blood cord gases, cognitive, behavior, sensory, sleeping, and feeding scores at 1 and 2 years of corrected age were not different. For the mothers, hemodynamic parameters, anesthesia duration, and the cumulative treatment dose until cord clamping did not differ between the groups.

CONCLUSIONS

The use of a low dose of remifentanil before cord clamping for a Cesarean section appears to be safe both for the mother and the preterm newborn, but it does not improve maternal or neonatal outcomes.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov: NCT02029898.