Remifentanil and propofol for sedation in children and young adolescents undergoing diagnostic flexible bronchoscopy

Effect of remimazolam besylate compared with propofol on the incidence of delirium after cardiac surgery: study protocol for a randomized trial

Background

Delirium is an acute cognitive disorder that presents with fluctuation in cognition, apathy, and non-organized thinking, resulting in increased morbidity, mortality, intensive care unit (ICU) stay, and total healthcare costs. In patients undergoing cardiac surgery, delirium also increases the risk of postoperative complications, such as respiratory insufficiency, sternum instability, and need for re-operation of the sternum. This study aims to understand the incidence of delirium in patients after cardiac surgery in patients sedated with remimazolam besylate versus propofol.

Methods

In this prospective, double-blind, randomized controlled clinical trial, we aim to recruit 200 patients undergoing cardiac surgery between January 1, 2021, and December 31, 2021, who will be randomized to receive either remimazolam besylate or propofol infusions postoperatively, until they are extubated. The primary outcome is the incidence of delirium within 5 days after surgery. Secondary outcomes include the time of delirium onset, duration of delirium, ICU length of stay, hospital length of stay, and mechanical ventilation time.

Discussion

The key objective of this study is to assess whether remimazolam besylate reduces the incidence of delirium in patients after cardiac surgery compared to propofol sedation. In this preliminary randomized controlled clinical trial, we will test the hypothesis that the use of remimazolam besylate lowers the incidence of delirium when compared to propofol in patients undergoing cardiac surgery.

Trial registration

chictr.org.cn ChiCTR2000038976. Registered on October 11, 2020

Bronchoscopy during COVID-19 pandemic, ventilatory strategies and procedure measures

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has changed bronchoscopy practices worldwide. Bronchoscopy is a high-risk aerosol-generating procedure with a potential for direct SARS-CoV-2 exposure and hospital-acquired infection. Current guidelines about personal protective equipment and environment considerations represent key competencies to minimize droplets dispersion and reduce the risk of transmission. Different measures should be put in field based on setting, patient's clinical characteristics, urgency and indications of bronchoscopy. The use of this technique in SARS-CoV-2 patients is reported primarily for removal of airway plugs and for obtaining microbiological culture samples. In mechanically ventilated patients with SARS-CoV-2, bronchoscopy is commonly used to manage complications such as hemoptysis, atelectasis or lung collapse when prone positioning, physiotherapy or recruitment maneuvers have failed. Further indications are represented by assistance during percutaneous tracheostomy. Continuous positive airway pressure, non-invasive ventilation support and high flow nasal cannula oxygen are frequently used in patient affected by Coronavirus Disease-2019 (COVID-19): management of patients' airways and ventilation strategies differs from bronchoscopy indications, patient's clinical status and in course or required ventilatory support. Sedation is usually administered by the pulmonologist (performing the bronchoscopy) or by the anesthetist depending on the complexity of the procedure and the level of sedation required. Finally, elective bronchoscopy for diagnostic indications during COVID-19 pandemic should be carried on respecting rigid standards which allow to minimize potential viral transmission, independently from patient's COVID-19 status. This narrative review aims to evaluate the indications, procedural measures and ventilatory strategies of bronchoscopy performed in different settings during COVID-19 pandemic.

Sedation for bronchoscopy in children: A prospective randomized double-blinded trial

INTRODUCTION

In pediatric patients, flexible bronchoscopy requires deep sedation. Different sedation regimes are common, but only some of them include opioids. Due to their antitussive effect, the use of short-acting opioids may be beneficial for this particular indication, but additional respiratory depression may lead to an increase in adverse events. Here, we systematically compared sedation regimes in children undergoing flexible bronchoscopy with either propofol alone, or a combination of propofol and remifentanil. The primary outcome parameter was the frequency of coughing episodes during the intervention. Secondary outcome parameters were frequency and types of complications, patient satisfaction, examiner satisfaction, and recovery time after finishing the sedation.

METHODS

Fifty children aged 1-17 years undergoing flexible bronchoscopy under deep sedation with propofol were randomly assigned to two groups: PR receiving propofol and remifentanil and PP receiving propofol only. Sedation depth was predefined as Comfort Score 10-13.

RESULTS

We found significantly less coughing episodes ([med (IQR)] PR: 0.73 (0.28-2.45)/min; PP: 1.98 (1.26-3.12)/min; p = .010) and shorter recovery time in Group PR (PR: 13.5 (8-17.5) min; PP: 21.0 (14-27) min; p = .011). Examiner's satisfaction was higher in Group PR (PR: 10 (8-10); PP: 9 (7-9); p = .012). The number of adverse events, patient satisfaction, and required propofol dose during the intervention did not differ between groups.

CONCLUSION

We suggest the combination of propofol with remifentanil instead of using propofol alone in pediatric procedural sedation for flexible bronchoscopy.

Analgosedation during flexible fiberoptic bronchoscopy: comparing the clinical effectiveness and safety of remifentanil versus midazolam/propofol

Background

There are limited data regarding the efficacy and safety of remifentanil sedation for diagnostic bronchoscopy. The aim of this study was to evaluate the clinical efficacy and safety of remifentanil by comparing it with those of conventional drugs, midazolam and propofol.

Methods

A retrospective study of 186 patients who underwent diagnostic bronchoscopy at Chonbuk National University Hospital was performed. Patients were classified into the remifentanil group and midazolam/propofol group according to the drugs used during bronchoscopy.

Results

Of the 186 patients, 111 patients received remifentanil and 75 received midazolam/propofol during the bronchoscopy. The proportion of patients who required bronchoscopy for endobronchial inspection alone was significantly higher in the midazolam/propofol group than in the remifentanil group (93.3% vs. 73.0%; p <  0.001). In contrast, the proportion of patients who required more invasive procedures, such as bronchoscopic biopsy, bronchoalveolar lavage, or transbronchial lung biopsy, was significantly higher in the remifentanil group than in the midazolam/propofol group (27.0% vs. 6.7%; p <  0.001). The recovery time was significantly shorter in the remifentanil group than in the midazolam/propofol group (mean 6.4 min vs. 11.6 min, p <  0.001). There were no significant differences between the groups with regard to safety events including desaturation, hypotension, and arrhythmia.

Conclusions

Despite the higher proportion of patients who underwent more invasive procedures in the remifentanil group than in the midazolam/propofol group, there was no significant difference in safety events between the groups. Those in the remifentanil group also demonstrated a faster recovery time than those in the midazolam/propofol group.

Dexmedetomidine-fentanyl versus propofol-fentanyl in flexible bronchoscopy: A randomized study

The aim of the present study was to evaluate the effect of a combination of dexmedetomidine and fentanyl on peripheral oxygen saturation (SpO₂) and hemodynamic stability in patients undergoing flexible bronchoscopy. One hundred patients undergoing elective flexible bronchoscopy were randomized into either a propofol-fentanyl group (PF group; n=50) or a dexmedetomidine-fentanyl group (DF group; n=50). SpO₂ values, heart rate (HR), systolic and diastolic blood pressure (SBP and DBP), patients' cough scores and discomfort scores as determined by patients and bronchoscopists, levels of sedation, number of times that additional lidocaine was required, elapsed time until recovery, and adverse events were recorded. The mean SpO₂ values in the DF group were significantly higher than those in the PF group (P<0.01), and HR, SBP and DBP were significantly lower in the DF group than in the PF group (P<0.05). There were no statistically significant differences between the two groups in terms of cough scores or discomfort scores, sedation levels, or number of times that additional lidocaine was required (P>0.05). Elapsed time until recovery in the DF group was significantly longer than in the PF group (P=0.002). The incidence of hypoxemia was significantly lower in the DF group than in the PF group (P=0.027), but the incidence of bradycardia was significantly higher in the DF group than in the PF group (P=0.037). Dexmedetomidine-fentanyl was superior to propofol-fentanyl in providing satisfactory SpO₂. Furthermore, dexmedetomidine-fentanyl attenuated hemodynamic responses during bronchoscopy and maintained hemodynamic stability in the early stage of the procedure.

Anaesthesia for bronchoscopy

Bronchoscopy as an investigation or therapeutic procedure demands anaesthesiologist to act accordingly. The present review will take the reader from rigid to fibreoptic flexible bronchoscopy. These procedures are now done as day care procedures in the operation theatre or in critical care units. Advantages and limitations of both rigid and flexible bronchoscopy are analysed. Recently, conscious sedation has come up as the commonly used anaesthetic technique for simple bronchoscopic procedures. However, general anaesthesia still remains a standard technique for more complex procedures. New advances in the field of anaesthesiology such as use of short acting opioids, use of newer drugs such as dexmedetomidine, supraglottic airways and mechanical jet ventilators have facilitated and eased the conduct of the procedure.

Propofol-ketamine or propofol-remifentanil for deep sedation and analgesia in pediatric patients undergoing burn dressing changes: a randomized clinical trial

OBJECTIVE

In this study, we compared the propofol-ketamine and propofol-remifentanil combinations for deep sedation and analgesia during pediatric burn wound dressing changes.

METHODS

Fifty pediatric patients aged 12-36 months, undergoing burn wound dressing changes, were randomly assigned to receive propofol-remifentanil (group PR) or propofol-ketamine (group PK) for deep sedation and analgesia. Patients in the group PR received 2 mg·kg(-1) propofol and 0.1 μg·kg(-1) remifentanil, and 0.05 μg·kg(-1) ·min(-1) remifentanil was infused continuously until the end of the procedure. Patients in the group PK received 2 mg·kg(-1) propofol and 1 mg·kg(-1) ketamine, and the same volume of isotonic saline was infused continuously until the end of the procedure. Additional propofol with remifentanil or ketamine was administered when required. Hemodynamic variables, drug requirements, occurrence of patient movement, surgeon's satisfaction score, recovery time, and the incidence of adverse events were recorded throughout the procedure and recovery.

RESULTS

Recovery time was significantly shorter in the group PR compared to that in the group PK (10.3 [9.1-11.5] min vs 22.5 [20.3-25.6] min, median [interquartile range], respectively; P < 0.001). No significant hypotension or bradycardia occurred throughout the procedure. No significant differences were observed in terms of drug requirements, occurrence of patient movement, surgeon's satisfaction, incidence of respiratory depression, hypoxia, or nausea and vomiting

CONCLUSIONS

The combinations of propofol-ketamine and propofol-remifentanil were effective for sedation and analgesia in pediatric patients undergoing burn dressing changes, but the propofol-remifentanil combination provided faster recovery compared to the propofol-ketamine combination.

Sedation monitoring during open muscle biopsy in children by Comfort Score and Bispectral Index - a prospective analysis

BACKGROUND

Open muscle biopsies in children are generally performed under general anesthesia. Alternatively, deep sedation and analgesia may be required.

OBJECTIVES

The aim of our study was to compare the Bispectral Index (BIS) and Comfort Score (CS) with respect to their clinical significance for sedation/analgesia in children undergoing open muscle biopsy.

METHODS

Thirty pediatric patients subjected to open muscle biopsy for diagnosis of their underlying disease were prospectively enrolled. Sedation/analgesia was performed in all patients using remifentanil and propofol. The patients were simultaneously monitored using the CS and BIS.

RESULTS

All sedations and muscle biopsies were performed uneventfully. The CS and BIS were significantly correlated (R = 0.589; P < 0.01). Receiver operating characteristic (ROC) analysis revealed an area under the curve (AUC) of 0.918 with a maximum cut-off point of BIS 70.5 (sensitivity 0.9; specificity 0.785) for adequate sedation. Sensitivity of 100% was achieved at BIS 60. Accordingly, all patients with BIS ≤60 had CS within the target range of 10-14. The BIS showed substantial intra- and interindividual variability (30 points and 58 points, respectively) during sedation, whereas CS varied only within close ranges during sedation. In 25 patients, sedatives were reduced according to low BIS values (<60). No unintended anesthesia awareness was noted during the study period.

CONCLUSION

Bispectral Index provides an additional helpful tool to guide sedation/analgesia in minor surgical procedures in children. BIS values ≤60 correlated with sufficient depth of sedation and prevented unintended awareness. Additionally, BIS measurement allowed for distinct regulation of depth of sedation without prolonged sedation/analgesia due to unintended overdose.

Effectiveness of high dose remifentanil in preventing coughing and laryngospasm in non-paralyzed patients for advanced bronchoscopic procedures

BACKGROUND:

Anesthesia for bronchoscopy presents unique challenges, as constant stimulus due to bronchoscope needs to be obtunded using drugs with a minimal post-procedure residual effect. Remifentanil for maintenance is an ideal choice, but optimal doses are yet to be determined.

MATERIALS AND METHODS:

Bronchoscopic procedures were prospectively evaluated for 4 months studying the frequency of complications and anesthesia techniques. Anesthesia was maintained on remifentanil/propofol infusion avoiding neuromuscular blockers. Laryngeal mask airway was used for the controlled ventilation (with high oxygen concentration) that also served as a conduit for bronchoscope insertions. Anesthesiologists were blinded to the study (avoiding performance bias) and the Pulmonologist was blinded to the anesthesia technique (to document unbiased procedural satisfaction scores). Procedures were divided into 2 groups based on the dose of remifentanil used for maintenance: Group-H (high dose −0.26 to 0.5 μg/kg/min and Group-NH (non-high dose ≤0.25 μg/kg/min).

RESULTS:

Observed 75 procedures were divided into Group-H (42) and Group-NH (33). Number of statistical difference was found in demography, procedural profile, hemodynamic parameters and total phenylephrine used. Chi-square test showed Group-NH had significantly higher frequency of laryngospasm (P = 0.047) and coughing (P = 0.002). The likelihood ratio of patient coughing and developing laryngospasm in Group-NH was found to be 4.56 and 10.97 times respectively. Minimum pulse-oximeter saturation was statistically higher in Group-H (98.80% vs. 96.50% P = 0.009). Pulmonologist satisfaction scores were significantly better in Group-H.

CONCLUSIONS:

High dose of remifentanil infusion is associated with a lower incidence of coughing and laryngospasms during bronchoscopy. Simultaneously, it improves Pulmonologist's satisfaction and procedural conditions.

Comparison of propofol and the combination of propofol and alfentanil during bronchoscopy: a randomized study

BACKGROUND

propofol is an excellent sedative agent for use in patients undergoing bronchoscopy. The addition of an opioid to propofol can be advantageous because of the antitussive effect of the opioid and the possible improvement in sedation quality. However, it may increase the risk of hypoxaemia. To investigate the effect of the addition of alfentanil to propofol, we performed a prospective study to compare propofol-only sedation with propofol-alfentanil combination sedation in patients undergoing bronchoscopy.

METHODS

patients were randomly assigned either to the propofol-only (group P, n=32) or to the propofol-alfentanil combination group (group PA, n=32). The average peripheral oxygen saturation (SpO(2) ) and the lowest SpO(2) during the sedation were compared. Patient and bronchoscopist satisfaction as well as the degree of coughing were compared using a 100 mm visual analogue scale, where 0 indicated the least and 100 indicated the most satisfied.

RESULTS

group P had the higher average SpO(2) (%) during the procedure than group PA (97.8 ± 1.6 and 96.4 ± 1.1, P<0.01) as well as the lowest SpO(2) (%) (95.4 ± 2.7 and 94.0 ± 2.4, P<0.05). Patient satisfaction (92.2 ± 13.5 and 92.3 ± 18.2), bronchoscopist satisfaction (76.6 ± 18.1 and 72.8 ± 19.1), and degree of cough (73.4 ± 22.7 and 72.2 ± 18.5; group P and group PA, respectively) were not different between the groups.

CONCLUSIONS

the combination of propofol and alfentanil resulted in a greater respiratory depression than propofol alone; furthermore, the addition of an opioid did not improve the quality of sedation. In conclusion, we do not recommend sedation with propofol and alfentanil during bronchoscopy.

Remifentanil, a different opioid: potential clinical applications and safety aspects

IMPORTANCE OF THE FIELD

Opioids play an important role in every aspect of modern anesthetic practice. Remifentanil is an ultra-short-acting opioid featuring a unique pharmacokinetic profile allowing clinical versatility and improved control of its action. In this review, we assess the pharmacology of remifentanil, its clinical uses as well as safety issues on its action on the major organ systems and in particular clinical settings.

AREAS COVERED IN THIS REVIEW

A synthesis of evidence from a MEDLINE search for articles from 1993 to 2009 for available up-to-date information on remifentanil and its current applications and safety profile.

WHAT THE READER WILL GAIN

A synopsis of the unique pharmacokinetic properties of remifentanil and its action on major organ systems will provide insight on the safe and effective use of the drug in a variety of clinical settings.

TAKE HOME MESSAGE

Remifentanil is a valuable opioid in the armamentarium of the clinician, providing great clinical flexibility and safety but vigilance is required to avoid pitfalls.

Sedation with propofol for flexible bronchoscopy in children

BACKGROUND

The purpose of this study was to report our experience with intravenous propofol (IVP) sedation for flexible bronchoscopy (FB) in children.

METHODS

The following data were collected: demographics, pre- and post-procedure diagnoses, induction time (IT), sedation time (ST), procedure time (PT), time to discharge from the hospital (TTD), induction dose (ID) of IVP, total dose (TD) of IVP, and complications. HR, RR, systolic BP (SBP), diastolic BP (DBP), and SpO(2) were recorded every 5 min.

RESULTS

One hundred three (66 males, 37 females) consecutive patients (age: 4.7 +/- 4.3 years) and (weight: 21.2 +/- 16 kg) were enrolled over a 3-year-period. Airway Abnormalities were diagnosed in 93 (90%) patients leading to a change in therapy in 68 (66%) patients. In 20 (19.4%) patients abnormalities unrelated to the primary indication for FB were found. IT was 4.64 +/- 2 min, PT was 6.2 +/- 3.1 min, ST was 27 +/- 14 min, and TTD was 80 +/- 44 min.The ID and TD for IVP were 2.8 +/- 0.1 mg/kg, and 3.1 +/- 0.1 mg/kg respectively. Patients 4-7 years of age required higher induction doses (IDs) of propofol (3.5 +/- 1 mg/kg) compared to infants (2.8 +/- 0.9 mg/kg), 1-3 years of age (2.7 +/- 0.78 mg/kg) and 8-17 years of age (2.4 +/- 0.7 mg/kg) (P < 0.001). There was a correlation between the TD of IVP and TTD from the hospital (r = 0.5, P < 0.01). The drop in SBP (104 +/- 15 vs. 92 +/- 13 mm Hg, P < 0.05) and DBP (57 +/- 13 vs. 46 +/- 9 mm Hg, P < 0.05) during IVP were statistically significant compared to baseline, however none of the patients met the criteria for hypotension. Two patients developed short (<20 sec) respiratory pauses without hypoxia. No patient required fluid resuscitation or endotracheal intubation.

CONCLUSIONS

FB may be performed successfully in children using IVP and is associated with insignificant cardio-respiratory complications.

Propofol and remifentanil for deep sedation in children undergoing gastrointestinal endoscopy

PURPOSE

The aim of this study was to evaluate the safety and efficacy of a combination of propofol and remifentanil deep sedation in spontaneously breathing children less than 7 years of age undergoing upper and/or lower gastrointestinal endoscopy.

METHODS

The effect of propofol and remifentanil sedation was prospectively studied in 42 unpremedicated children undergoing gastrointestinal endoscopy. Anesthesia was induced with a combination of sevoflurane, nitrous oxide and oxygen. Anesthesia was maintained with an infusion of propofol (50-80 microg x kg(-1) x min(-1)) and remifentanil (0.1 microg x kg(-1) x min(-1)). Demographic data, heart rate, blood pressure, respiratory rate, and oxygen saturation were recorded every 5 min for each child. In addition, recovery and discharge times were recorded.

RESULTS

All 42 procedures were completed with no complications. The combination of propofol and remifentanil resulted in a decrease in heart rate, blood pressure, and respiratory rate. There was no respiratory depression or oxygen desaturation in any child. A bolus of propofol (1 mg x kg(-1)) was necessary in one child for excessive movement. No patient experienced any side effects in the recovery period.

CONCLUSION

The combination of propofol and remifentanil for sedation in children undergoing gastrointestinal endoscopy can be considered safe, effective and acceptable.

Sedation and analgesia for brief diagnostic and therapeutic procedures in children

The number of diagnostic and therapeutic procedures done outside of the operating room and the intensive care unit has increased substantially in recent years. In parallel, the management of acute pain and anxiety in children undergoing therapeutic and diagnostic procedures has developed considerably in the past two decades. The primary goal of procedural sedation and analgesia is the safe and efficacious control of emotional distress and pain. The availability of non-invasive monitoring, short-acting opioids and sedatives has broadened the possibilities of sedation and analgesia in children in diverse settings. While most of these procedures themselves pose little risk to the child, the administration of sedation or analgesia may add substantial risk to the patient. This article reviews the current status of sedation and analgesia for invasive and non-invasive procedures in children providing an evidence-based approach to several topics of importance, including patient assessment, personnel requirements, equipment, monitoring, and drugs.

Experience with remifentanil in neonates and infants

Remifentanil is a relatively new synthetic opioid, which is not licensed worldwide for neonates and infants. Because of its unique pharmacokinetic properties with a short recovery profile, it could be the ideal opioid for neonates and infants, who are especially sensitive to respiratory depression by opioids. Therefore, we conducted a MEDLINE search on all articles dealing with the use of remifentanil in this important subgroup of patients. Most experience with remifentanil in neonates and infants is as maintenance anaesthesia during surgery. In approximately 300 neonates and infants, remifentanil proved to be an effective and safely used opioid for this indication. However, very limited data exist on remifentanil for analgesia and sedation of mechanically ventilated paediatric intensive care patients. Further research with remifentanil in neonates and infants should focus on this group of patients because remifentanil, with its very short context-sensitive half-life, could result in shorter extubation times compared with commonly used opioids such as morphine or fentanyl.

Evaluation of propofol and remifentanil for intravenous sedation for reducing shoulder dislocations in the emergency department

OBJECTIVES

To assess the combination of propofol and remifentanil for sedation to reduce shoulder dislocations in an ED.

METHODS

Eleven patients with anterior glenohumeral dislocation were given propofol 0.5 mg/kg and remifentanil 0.5 microg/kg iv over 90 seconds and then further doses of 0.25 mg/kg and 0.25 microg/kg, respectively, if needed. Another practitioner attempted reduction using the Milch technique.

RESULTS

Reduction was achieved in all patients within four minutes of giving sedation (range 0.3-4; mean 1.6). Seven required one attempt at shoulder reduction, three required two attempts, and one required three attempts. Mean time to recovery of alert status was three minutes (range 1-6). The mean pain score during the reduction was 1.7 out of 10 (range 0-5). Nine patients had full recall, one had partial recall, and one had no recall at all. Eight patients were "very satisfied" with the sedation and three were "satisfied". There were no respiratory or haemodynamic complications that required treatment.

CONCLUSIONS

Propofol and remifentanil provide excellent sedation and analgesia for the reduction of anterior glenohumeral dislocation, enabling rapid recovery.

Comparison of remifentanil with fentanyl for deep sedation in oral surgery

PURPOSE

The aim of this study was to compare recovery for oral surgery patients given a deep sedation regimen of midazolam, propofol, and remifentanil with a standard control of fentanyl in place of remifentanil.

MATERIALS AND METHODS

This investigation was designed as a randomized, prospective, single-blinded controlled study. Group 1, the control, received midazolam 0.03 mg/kg, fentanyl 1 microg/kg, and propofol initially at 140 microg/kg/min. Group 2 received midazolam 0.03 mg/kg, remifentanil: propofol (1:500) given at an initial propofol infusion rate of 40 microg/kg/min. Outcome measures included time to response to verbal command, Aldrete score = 9, Postanesthesia Discharge Scoring System = 7, and assessment by the Digit Symbol Substitution Test.

RESULTS

Forty-seven subjects were entered in the study. Baseline findings were homogenous between the 2 groups. Subjects in group 2 recovered earlier (P < .005) and required less propofol for both the induction (0.8 +/- 0.4 versus 1.2 +/- 0.6 mg/kg; mean +/- SD, P < .01) and maintenance of deep sedation (46 +/- 9 versus 131 +/- 17 microg/kg/min; P < .005). There were minor differences in vital signs.

CONCLUSIONS

This study demonstrated that this remifentanil regimen provided significantly more rapid recovery and used significantly less propofol compared with the fentanyl regimen.

Recovery After Anesthesia for Short Pediatric Oncology Procedures: Propofol and Remifentanil Compared with Propofol, Nitrous Oxide, and Sevoflurane

Anesthesia techniques in children undergoing short painful oncology procedures should allow rapid recovery without side effects. We compared the recovery characteristics of two anesthetic techniques: propofol with sevoflurane and nitrous oxide and a total IV technique using propofol and remifentanil. Twenty-one children, undergoing two similar painful procedures within 2 wk were studied in a single-blind manner within patient comparison. The order of the techniques was randomized. Propofol and remifentanil involved bolus doses of both propofol 3-5 mg/kg and remifentanil 1-4 microg/kg. Propofol with sevoflurane and nitrous oxide involved propofol 3-5 mg/kg with 2%-8% sevoflurane and 70% nitrous oxide. The primary outcome variable was the time taken to achieve recovery discharge criteria; other recovery characteristics were also noted. The mean age of the children was 6.5 yr (range, 2.5-9.8 yr). Nineteen had lymphoblastic leukemia and two had lymphoma. All children had intrathecal chemotherapy and one had bone marrow aspiration. Most procedures lasted <4 min. The mean time to achieve recovery discharge criteria was appreciably shorter after propofol and remifentanil than propofol with sevoflurane and nitrous oxide by nearly 19 min (P = 0.001). All other time comparisons had similar trends and statistical differences. Seven parents expressed a preference for the propofol and remifentanil technique compared with one preferring propofol with sevoflurane and nitrous oxide. Children are apneic during the procedure and require respiratory support from an anesthesiologist. Discharge readiness from the recovery ward was achieved on average 19 min earlier after propofol with remifentanil compared with the combination of propofol, sevoflurane and nitrous oxide. Parents more often preferred propofol with remifentanil.

Remifentanil update: clinical science and utility

The anilidopiperidine opioid remifentanil has pharmacodynamic properties similar to all opioids; however, its pharmacokinetic characteristics are unique. Favourable pharmacokinetic properties, minimally altered by extremes of age or renal or hepatic dysfunction, enable easy titration and rapid dissipation of clinical effect of this agent, even after prolonged infusion. Remifentanil is metabolised by esterases that are widespread throughout the plasma, red blood cells, and interstitial tissues, whereas other anilidopiperidine opioids (e.g. fentanyl, alfentanil and sufentanil) depend upon hepatic biotransformation and renal excretion for elimination. Consequently, remifentanil is cleared considerably more rapidly than other anilidopiperidine opioids. In addition, its pKa (the pH at which the drug is 50% ionised) is less than physiological pH; thus, remifentanil circulates primarily in the non-ionised moiety, which quickly penetrates the lipid blood-brain barrier and rapidly equilibrates across the plasma/effect site interface. By virtue of these distinctive pharmacokinetic properties, the context-sensitive half-time (i.e. the time required for the drug's plasma concentration to decrease by 50% after cessation of an infusion) of remifentanil remains consistently short (3.2 minutes), even following an infusion of long duration (> or =8 hours). Remifentanil, a clinically versatile opioid, is useful for intravenous analgesia and sedation in spontaneously breathing patients undergoing painful procedures. Profound analgesia may be achieved with minimal effect on cognitive function. Remifentanil may also provide sedation and analgesia during placement of regional anaesthetic blocks, and in conjunction with topical anaesthesia and airway nerve blocks, it may be useful for blunting reflex responses and facilitating 'awake' fibreoptic intubation. Compared with fentanyl and alfentanil in a day-surgery setting, remifentanil supplementation of general anaesthesia may improve intraoperative haemodynamic control. Both emergence time and the incidence of respiratory depression during post-anaesthetic recovery may be reduced. However, outcomes such as home discharge time, post-emergence adverse effect profile, and patient and provider satisfaction are not significantly improved, and the incidence of intraoperative hypotension and bradycardia is greater. In addition, drug acquisition costs for remifentanil are higher and clinicians may need extra time to familiarise themselves with the drug's unique pharmacokinetics.Ironically, the quick dissipation of opioid analgesic effect following remifentanil discontinuation may be a significant clinical disadvantage. Unless little or no postoperative pain is anticipated, the clinician may wish to treat prospectively using local or regional anaesthesia, non-opioid analgesics, or longer-acting opioid analgesics.

Review of pediatric sedation

Sedating children for diagnostic and therapeutic procedures remains an area of rapid change and considerable controversy. Exploration of this topic is made difficult by the fact that the reports of techniques and outcomes for pediatric sedation appear in a wide range of subspecialty publications and rarely undergo comprehensive examination. In this review article, we will touch on many aspects of the topic of pediatric sedation from the perspective of the anesthesiologist. We begin with a review of the historical role of anesthesiologists in the development of the current standards for pediatric sedation. We also examine the current status of pediatric sedation as reflected in published studies and reports. A specific review of the issues surrounding safety of sedation services is included. Current trends in sedation practice, including the expanding role of potent sedative hypnotic drugs outside the field of anesthesiology, are noted. Finally, we suggest future areas for research and clinical improvement for sedation providers.

Use of a remifentanil-propofol mixture for pediatric flexible fiberoptic bronchoscopy sedation

BACKGROUND

Flexible fiberoptic bronchoscopy is an important diagnostic tool for pediatric pulmonologists. Because of its favorable respiratory profile, ketamine has become a popular sedative for this procedure, but may be associated with unpleasant emergence reactions in the older child. Remifentanil is a newer, ultra-short acting opioid that has been shown to provide effective sedation and cough suppression for fiberoptic bronchoscopy when combined with intermittent propofol boluses. However, delivery of these agents as a combined, single infusion has not been described.

METHODS

Children > or =2 years of age undergoing fiberoptic bronchoscopy were enrolled. Remifentanil was mixed in a single syringe with undiluted propofol giving final drug concentrations of 10 mg x ml(-1) of propofol and 15-20 microg x ml(-1) of remifentanil. Sedation was induced with a bolus of approximately 0.1 ml x kg(-1) of this mixture and maintained by titrating the drip throughout the procedure. Vital signs, sedative effectiveness, recovery patterns, and complications were prospectively recorded.

RESULTS

Fifteen patients aged 9.0 +/- 5.3 years were sedated. Sedation was induced with 1.2 +/- 0.4 mg x kg(-1) propofol (2.4 +/- 0.8 microg x kg(-1) remifentanil) and maintained with 4.1 +/- 1.8 mg x kg(-1) x h(-1) propofol (0.13 +/- 0.06 microg x kg(-1) x min(-1) remifentanil). Five patients received low-dose ketamine to augment sedation. The maximal decrease in respiratory rate was 6.1 +/- 5.3 b x min(-1) (27.6 +/- 21%) and no patient became hypoxemic. All procedures were completed easily without significant complication. Patients recovered to baseline 13.3 +/- 8.5 min following infusion discontinuation.

CONCLUSIONS

A remifentanil/propofol mixture provided effective sedation and rapid recovery in pediatric patients undergoing fiberoptic bronchoscopy.

Bronchoscopist talks to you

Fiberoptic bronchoscopy (FBS) is an important entry in the armamentarium of procedures listed in management of respiratory problems. It is a simple and a safe procedure. FBS has a great scope for diagnosis as well as therapy in pediatric respiratory illnesses. This article gives a practical overview of FBS in pediatric practice.

Broncoscopia flexible en el niño: indicaciones y aspectos generales

There is considerable interhospital variability in the practice of flexible bronchoscopy in children. The present report aims to provide some recommendations that are supported by the Spanish Society of Pediatric Pulmonologists. We review the indications, contraindications, equipment, setting and personnel involved in flexible bronchoscopy, as well as the pre-procedure preparation of the patient, medications, post-procedure monitoring, complications, care and maintenance of instruments, and informed consent. These recommendations may be adopted, modified or rejected according to clinical needs and constraints.

Fibrobroncoscopia en el niño con ventilación mecánica

Fiberoptic bronchoscopy can be performed at the patient's bedside. This technique allows direct visualization of the upper and lower airways up to the segmental and subsegmental bronchi. Its most frequent indications are airway examination ot evaluate damage produced by toxins or the endotracheal tube, patency of the endotracheal tube and extubation failure. It is also used to obtain microbiological samples, facilitate intubation when difficult, aspirate airway sections or mucus plugs, perform bronchoalveolar lavage and administer drugs. With prior preparation, adequate monitoring and sedation, material according to the size of the patient and correct techniques, there are few complications. However, the procedure can produce trauma and obstruction of the airway, bronchial hemorrhage, barotrauma, loss of alveolar recruitment, bronchospasm, hypoxemia, bradycardia, and bronchopulmonary infection.

Awake fibreoptic intubation under remifentanil and propofol target-controlled infusion

We present the first report of the use of remifentanil and propofol target-controlled infusion to sedate a patient with a difficult airway undergoing awake fibreoptic intubation. This regimen was rapidly titratable, aided suppression of airway reflexes, maintained patient comfort and cooperation and did not compromise spontaneous respiration. The literature regarding infusion rates and potential complications of this technique is reviewed.

Propofol/remifentanil versus propofol alone for bone marrow aspiration in paediatric haemato-oncological patients

BACKGROUND

This prospective randomized study was designed to evaluate the effects of adding remifentanil to the standard propofol-based technique in the setting of paediatric haematology-oncology outpatient clinic.

METHODS

Eighty ASA III paediatric patients treated in the outpatient haematology-oncology clinic requiring bone marrow aspiration were randomly assigned either to the propofol (P) or the propofol/remifentanil (PR) group. The quality of anaesthesia and recovery were evaluated.

RESULTS

The total amount of propofol required to prevent patient movement was lower in the PR group. The time interval to eye opening and to home readiness was significantly lower in the PR group. Adverse respiratory events (RR < 10.min-1 or SpO2 < 90%) occurred significantly more in the propofol/remifentanil group.

CONCLUSIONS

The addition of remifentanil improved the conditions during the procedure and reduced the total amount of propofol, as well as the time to home readiness. However, the addition of remifentanil is associated with an increased risk of respiratory depression.

Pediatric bronchoscopy

Diagnostic flexible endoscopy for pediatric respiratory diseases is performed in many centers. Technical advances have resulted in performance of interventional bronchoscopies, and new diagnostic indications are being explored. Indications with documented clinical benefit include congenital or acquired progressive or unexplained airway obstruction. Pulmonary infections in immunodeficient children who do not respond to empirical antibiotic treatment may be diagnosed by bronchoscopy and bronchoalveolar lavage (BAL). The potential usefulness of bronchoscopy and BAL for managing chronic cough, wheeze, or selected cases with asthma or cystic fibrosis requires further study. The use of transbronchial biopsies (TBB) is established in pediatric lung transplantation. The role of TBB in the diagnosis of chronic interstitial lung disease in children remains to be determined. For a number of interventional applications, rigid endoscopy is required, and pediatric bronchoscopists should be trained in its use. Complications in pediatric bronchoscopy are rare, but severe nosocomial infection or overdosing with local anesthetics has occurred. The issues of quality control, video documentation, interobserver variability of findings, and educational standards will have to be addressed in the future as bronchoscopy use becomes less restricted to only large pediatric pulmonary units.

Controversial issues in adult and paediatric ambulatory anaesthesia: is there a role for alpha-2 agonists in conscious sedation in adults and paediatric ambulatory surgical practice?

Ambulatory surgery has come to the fore in recent years, guided by the twin forces of healthcare economics and pharmacological innovations. In this review the authors will focus on alpha2-adrenergic agonists, a new class of sedative/analgesic agents and their possible application for conscious sedation in the ambulatory care setting. To put the alpha2-agonists into clinical context, we will discuss the currently available agents for general anaesthesia as well as for conscious sedation and their respective drawbacks. Thereafter we will compare and contrast the use of alpha2-agonists with clinically available agents, and speculate as to the direction this field is likely to take in the future.

Pharmacokinetics and pharmacodynamics of remifentanil: an update in the year 2000

Remifentanil is still in its infancy in terms of postmarketing development. Its appropriate role in modern anesthesia care is still being defined and reports of novel clinical applications for remifentanil are frequently appearing in the anesthesia literature. This review will focus on selected advances in our understanding of remifentanil pharmacokinetics and pharmacodynamics and on newly proposed clinical applications for remifentanil.