Continuous infusion versus intermittent bolus injection of propofol during endoscopic retrograde cholangiopancreatography

Determining the Target Concentration of Propofol for Sedation in Patients Undergoing Endoscopic Retrograde Cholangiopancreatography: A Target-Controlled Infusion Approach

Introduction Endoscopic retrograde cholangiopancreatography (ERCP) is vital for diagnosing and treating biliary and pancreatic diseases, necessitating deep sedation typically achieved through total intravenous anesthesia. Propofol, with its favorable pharmacokinetic profile, is the preferred sedative, but conventional administration methods of mg/kg boluses or infusion rates pose challenges. Target-controlled infusion (TCI) systems offer a solution that ensures precise dose delivery of propofol. Despite its widespread use, the literature lacks specific guidance on the target plasma concentration (Cp) of propofol for sedation in patients undergoing ERCP. Methods A prospective interventional study was conducted at the Institute of Liver and Biliary Sciences, Delhi, India to determine the target Cp of propofol for sedation during ERCP. The study enrolled 86 American Society of Anesthesiologists (ASA) grade I and II patients aged 18-70 years. The primary objective was to establish the optimal propofol concentration for sedation as guided by a bispectral index (BIS) value of 60-70. Secondary outcomes included induction time, recovery time, total propofol consumption, and the occurrence of adverse events (if any). The Marsh pharmacokinetic model guided the TCI pump, adjusting Cp until the target sedation was achieved. Results The mean Cp of propofol to maintain the BIS value 60-70 was 2.21 ± 0.42 µg/ml. Age-wise analysis revealed variations, emphasizing the need for individualized dosing. Induction time was 4.21 ± 0.68 minutes; recovery times were seven minutes (median, IQR: 5-10 minutes) for BIS >80 and seven minutes (median, IQR: 5-10 minutes) for achieving a Modified Observer's Assessment of Alertness/Sedation score of ≥5. The mean propofol consumption was 6.24 mg/kg/hr. Side effects were minimal, with 1.16% experiencing transient hypoxia and hypotension. Conclusion The study establishes a mean target propofol concentration of 2.21 ± 0.42 µg/ml for sedation in ASA I and II patients undergoing ERCP.

Benefits of remimazolam as an anesthetic sedative for older patients: A review

Owing to the decreased levels of receptors in the peripheral and central nervous systems, the functions of various organ systems decline in older patients. When administering anesthesia to older patients, it is necessary to consider the effects of medication on the homeostatic balance. Remimazolam, a new benzodiazepine, was recently developed as an anesthetic drug that has shown promise in clinical anesthesia application owing to its molecular structure, targets, pharmacodynamics, and pharmacokinetic characteristics. Remimazolam exhibits a rapid onset and metabolism, with minor effects on liver and kidney functions. Moreover, the drug has a specific antagonist, flumazenil. It is safer to use in older patients than other anesthetic sedatives and has been widely used since its introduction. Comparisons of the pharmacokinetics, metabolic pathways, effects on target organs, and hemodynamics of different drugs with those of commonly used anesthetic sedative drugs are useful to inform clinical practice. This article elaborates on the benefits of remimazolam compared with those of other anesthetic sedatives for sedation in older patients to demonstrate how it offers a new option for anesthetics in older patients. In cases involving older patients with increased clinical complexities or very old patients requiring anesthesia, remimazolam can be selected as the preferred anesthetic sedative, as outlined in this review.

Dexmedetomidine as an Adjunct to Propofol in Patients Undergoing Elective Endoscopic Retrograde Cholangio-Pancreaticography - A Double-blind Randomized Controlled Study

Background

Propofol is the drug of choice for procedural sedation. The addition of α2 agonist dexmedetomidine may improve the safety profile of the procedure by providing stable hemodynamics, better sedation quality, and decreasing the side effects of each drug during elective endoscopic retrograde cholangio-pancreaticography (ERCP).

Materials and Methods

Eighty patients aged between 18 and 60 years were distributed randomly into two groups. The dexmedetomidine + propofol group (group DP) received an injection of dexmedetomidine at the dose of 1 mcg/kg in 100 mLsaline, and the propofol group (group P) received plain 100 mL normal saline over 10 min. Subsequently, both groups received a bolus dose of injection propofol 1 mg/kg as sedation, and a modified observer's assessment of alertness/sedation score (MOASS) score was assessed, followed by infusion at the rate of 50 mcg/kg/min during the procedure. A rescue bolus dose (20 mg) of propofol was administered when the patient showed signs of inadequate sedation or analgesia in both groups. Cardiovascular and respiratory parameters were recorded every 10 min throughout the procedure. Post-procedure modified Aldrete score was evaluated for 30 min, and the endoscopist's score was noted at the end of the procedure.

Results

There was a significant difference (P = 0.001) in the additional number of rescue doses of propofol administered in group DP (3.47 ± 0.77) as compared to group P (8.78 ± 1.11). The total dose of propofol was lower in group DP (316.59 ± 43.29 mg) than in group P (443 ± 41.1 mg) with P value = 0.001. Statistically significant differences in the hemodynamic values were observed in group DP during infusion (P value < 0.05) of dexmedetomidine and throughout the procedure (P < 0.05) when compared with group P. Endoscopists graded the satisfaction score as very high (3.477 ± 0.77) in group DP.

Conclusion

The addition of dexmedetomidine to propofol during ERCP provided better and safer sedation.

Infusion of propofol with bispectral index monitoring does not reduce the amount of propofol used during transvaginal oocyte retrieval procedure

In our study we aimed to investigate whether the use of bispectral index (BIS) monitoring would decrease total propofol consumption during the transvaginal oocyte retrieval procedure. This was a prospective, randomized, controlled, parallel-group clinical trial. The study was conducted in the operating room, and postoperative recovery room. One hundred and thirty, American Society of Anesthesiologists (ASA) I-II patients, over age 18, undergoing transvaginal oocyte retrieval were included in this study. All patients were administered 2 μg/kg fentanyl, and 2 mg/kg propofol for the induction of anesthesia. The patients were divided into two groups. Patients in the group bolus were given 0.5 mg/kg of propofol when necessary, according to the observer's range of motion. Patients in the group BIS were given 10 mg/kg/h propofol infusion adjusted to keep the BIS value between 40 and 60. The primary outcome was the total dose of propofol administered per patient. The secondary outcomes were the time to reach the value of 5 on the Modified Observer's Assessment of Alertness Sedation Scale (MOASs), the time to reach Post Anesthetic Discharge Scoring System (PADSS) ≥ 9 of the patients, satisfaction of the patient, and the gynecologist. The amount of total propofol was higher in the group BIS than in the group bolus administered according to the patient's clinic. There was no difference in the time to reach the value of 5 on the MOASs between the groups. The time to reach PADSS ≥ 9 was longer in the group BIS than in the group bolus. There was no difference between the two groups in terms of the satisfaction of the patient and the gynecologist. Administration of propofol as an infusion with BIS monitoring did not reduce the amount of propofol administered to patients during transvaginal oocyte retrieval.Clinical trial registration number: NCT05631925-30/11/2022.

Clinical effects of remimazolam alone or in combination with dexmedetomidine in patients receiving bronchoscopy and influences on postoperative cognitive function: a randomized-controlled trial

BACKGROUND

Remimazolam and dexmedetomidine are commonly used as sedatives. However, the effects and safety of remimazolam alone or in combination with dexmedetomidine have not been investigated.

AIM

We sought to investigate the clinical effects of remimazolam alone or in combination with dexmedetomidine in bronchoscopy, and their influence on cognitive function.

METHOD

Ninety eligible patients who underwent bronchoscopy under intravenous anesthesia were randomly divided into three groups: propofol control, remimazolam, and remimazolam plus dexmedetomidine. The primary outcome was the incidence of perioperative hypoxemia. Secondary outcomes included induction and maintenance doses of remimazolam, hemodynamic variables, scores for modified Observer's Assessment of Alertness/Sedation (MOAA/S), coughing, limb movement, incidence of adverse events, patient satisfaction, bronchoscopist satisfaction, incidence of post-operative cognitive dysfunction (POCD), time to loss of consciousness (LoC), and time to awake.

RESULTS

The incidence of hypoxemia, hypotension, and bronchoscopist satisfaction score were significantly decreased, and time to LoC and time to awake were markedly longer in the remimazolam and remimazolam plus dexmedetomidine groups than in the propofol control group (p < 0.05). The remimazolam group had significantly decreased induction and maintenance doses of remimazolam and a shorter time to LoC than the remimazolam plus dexmedetomidine group (p < 0.05). Scores for coughing, limb movement, MOAA/S, and post-operative patient satisfaction were comparable among the three groups. POCD was not induced in any of the groups.

CONCLUSION

Remimazolam is safe and effective for painless bronchoscopy, with a low incidence of adverse reactions, and exhibits a good synergistic effect with dexmedetomidine.

TRIAL REGISTRATION

This trial protocol had been registered on Chinese Clinical Trial Registry (ChiCTR2000041435, date: 2020 12 26.

Effectiveness of single loading dose of dexmedetomidine combined with propofol for deep sedation of endoscopic retrograde cholangiopancreatography (ERCP) in elderly patients: a prospective randomized study

Background

Endoscopic retrograde cholangiopancreatography (ERCP) is an advanced endoscopic procedure and requires deep sedation. Deep sedation with dexmedetomidine for the respiratory drive preserved has become popular in recent years. However, the use of dexmedetomidine in elderly patients is controversial because its adverse events are more common. The objective of this study was to investigate the effectiveness of a single loading dose of dexmedetomidine combined with propofol for deep sedation of ERCP in elderly patients.

Methods

In this prospective randomized trial, 49 elderly patients undergoing ERCP were randomly allocated to the dexmedetomidine (DEX) or propofol (PRO) groups. The single loading dose of dexmedetomidine was set at 0.5 μg/kg at the start of anesthesia induction and loading for 10 min. The primary outcome was the cumulative dose of propofol. Secondary outcomes included time to awake, the frequency of airway interventions, and hemodynamics.

Results

The intraoperative cumulative dose of propofol was lower in the DEX group (111.0 ± 12.6 μg/kg/min) than the PRO group (143.7 ± 23.4 μg/kg/min) (P < 0.001). There was no statistically significant difference in the time to awake between the two groups. The incidence of artificial airway interventions and hypotension in the PRO group (36%, 60%) were significantly higher than those in the DEX group (4.2%, 16.7%) (P = 0.011, P = 0.003, respectively). In addition, the occurrence of bradycardia increased significantly in the DEX group (58.3%) compared with the PRO group (12%) (P < 0.001).

Conclusions

The single loading dose of dexmedetomidine combined with propofol can reduce propofol consumption and artificial airway intervention and provide better hemodynamic stability than propofol for deep sedation in elderly patients during ERCP.

Trial registration

www.chictr.org.cn (Registration number ChiCTR1900028069, Registration date 10/12/2019).

Safety and efficacy of ciprofol vs propofol for sedation in intensive care unit patients with mechanical ventilation: a multi-center, open label, randomized, phase 2 trial

Background:

Ciprofol (HSK3486; Haisco Pharmaceutical Group Co., Ltd., Chengdu, China), developed as a novel 2,6-disubstituted phenol derivative showed similar tolerability and efficacy characteristics as propofol when applicated as continuous intravenous infusion for 12 h maintenance sedation in a previous phase 1 trial. The phase 2 trial was designed to investigate the safety, efficacy, and pharmacokinetic characteristics of ciprofol for sedation of patients undergoing mechanical ventilation.

Methods:

In this multicenter, open label, randomized, propofol positive-controlled, phase 2 trial, 39 Chinese intensive care unit patients receiving mechanical ventilation were enrolled and randomly assigned to a ciprofol or propofol group in a 2:1 ratio. The ciprofol infusion was started with a loading infusion of 0.1–0.2 mg/kg for 0.5–5.0 min, followed by an initial maintenance infusion rate of 0.30 mg·kg⁻¹·h⁻¹, which could be adjusted to an infusion rate of 0.06 to 0.80 mg·kg⁻¹·h⁻¹, whereas for propofol the loading infusion dose was 0.5–1.0 mg/kg for 0.5–5.0 min, followed by an initial maintenance infusion rate of 1.50 mg·kg⁻¹·h⁻¹, which could be adjusted to 0.30–4.00 mg·kg⁻¹·h⁻¹ to achieve −2 to +1 Richmond Agitation-Sedation Scale sedation within 6–24 h of drug administration.

Results:

Of the 39 enrolled patients, 36 completed the trial. The median (min, max) of the average time to sedation compliance values for ciprofol and propofol were 60.0 (52.6, 60.0) min and 60.0 (55.2, 60.0) min, with median difference of 0.00 (95% confidence interval: 0.00, 0.00). In total, 29 (74.4%) patients comprising 18 (69.2%) in the ciprofol and 11 (84.6%) in the propofol group experienced 86 treatment emergent adverse events (TEAEs), the majority being of severity grade 1 or 2. Drug- and sedation-related TEAEs were hypotension (7.7% vs. 23.1%, P = 0.310) and sinus bradycardia (3.8% vs. 7.7%, P = 1.000) in the ciprofol and propofol groups, respectively. The plasma concentration-time curves for ciprofol and propofol were similar.

Conclusions:

ciprofol is comparable to propofol with good tolerance and efficacy for sedation of Chinese intensive care unit patients undergoing mechanical ventilation in the present study setting.

Trial registration:

ClinicalTrials.gov, NCT04147416.

The Efficacy and Safety of Remimazolam Tosilate versus Etomidate-Propofol in Elderly Outpatients Undergoing Colonoscopy: A Prospective, Randomized, Single-Blind, Non-Inferiority Trial

Objective

The optimal sedation regime during endoscopy remains controversial, especially for elderly outpatients. In this study, we compared the efficacy and safety between remimazolam tosilate (RT) and etomidate-propofol (EP) in elderly outpatients undergoing colonoscopy.

Methods

A total of 260 elderly outpatients undergoing sedative colonoscopy were randomized into two groups. Patients in the RT group received a 0.075-mg/kg maintenance dose of remimazolam following an initial dose of 0.15 mg/kg, whereas patients in the EP group (10 mL:20 mg etomidate plus 10 mL:100 mg propofol) received a 0.05-mL/kg maintenance dose following an initial dose of 0.1 mL/kg to maintain a Modified Observer’s Assessment of Alertness/Sedation score of ≤3 during the procedure. The primary endpoint was the success of the procedure. Secondary endpoints included time metrics, hemodynamics, consumption of fentanyl, etomidate, propofol, and remimazolam, intraoperative body movement, patient and endoscopist satisfaction scores, supplemental dose of sedative and fentanyl, and incidence and severity of adverse events.

Results

The procedure success rate was 96.52% in the RT group and 100% in the EP group. The difference in procedure success rate between the RT and EP groups was −3.48% (95% confidence interval: −6.81%, −0.15%). Four patients in the RT group required rescue midazolam. Compared with patients in the RT group, the onset time of the EP group was significantly lower (p < 0.05), whereas time to fully alert (p = 0.001), ready for discharge (p = 0.001), and hospital discharge (p = 0.002) were all significantly higher in the EP group. However, there were no significant differences in procedure time (p = 0.846) or cecal intubation time (p = 0.320) between the two groups. Although the frequency of intraoperative body movement was higher in the RT group, the difference was not significant (p = 0.508). There were no significant differences in patients’ demographic and baseline characteristics, supplemental doses of sedative and fentanyl, or patient and endoscopist satisfaction scores (p > 0.05). Muscular tremor and pain on injection were recorded more frequently in the EP group (p < 0.05). However, there were no significant differences in hypoxia, respiratory depression, or incidence of postoperative nausea and vomiting. The severity of adverse events was all mild (grade 1) across both groups.

Conclusion

RT may have non-inferior efficacy and a higher safety profile than EP in elderly outpatients undergoing colonoscopy, which suggests that RT may be more suitable for elderly outpatients undergoing colonoscopy.

Patient monitoring in the nonoperating room anesthesia (NORA) setting: current advances in technology

PURPOSE OF REVIEW

Nonoperating room anesthesia (NORA) procedures continue to increase in type and complexity as procedural medicine makes technical advances. Patients presenting for NORA procedures are also older and sicker than ever. Commensurate with the requirements of procedural medicine, anesthetic monitoring must meet the American Society of Anesthesiologists standards for basic monitoring.

RECENT FINDINGS

There have been improvements in the required monitors that are used for intraoperative patient care. Some of these changes have been with new technologies and others have occurred with software refinements. In addition, specialized monitoring devises have also been introduced into NORA locations (depth of hypnosis, respiratory monitoring, point-of care ultrasound). These additions to the monitoring tools available to the anesthesiologist working in the NORA-environment push the boundaries of procedures which may be accomplished in this setting.

SUMMARY

NORA procedures constitute a growing percentage of total administered anesthetics. There is no difference in the monitoring standard between that of an anesthetic administered in an operating room and a NORA location. Anesthesiologists in the NORA setting must have the same compendium of monitors available as do their colleagues working in the operating suite.