The effective dose of remimazolam in adult gastroscopy

OBJECTIVES

The objectives of this study were to explore the median effective dose (ED50) and the dose required for successful anesthesia in 95% of the patients (ED95) of remimazolam for intravenous anesthesia in adult outpatients undergoing gastroscopy.

METHODS

This pilot study was conducted in patients scheduled to undergo painless gastroscopy at the authors' hospital between March 15, 2022 and March 25, 2022. The ED of remimazolam was determined using the modified Dixon sequential method, using an initial induction dose of 0.2 mg/kg. With successful or failed anesthesia, the remimazolam dose was decreased or increased by 0.05 mg/kg for the next patient, respectively.

RESULTS

Twenty-two patients (43.6 ± 10.5 years of age) were enrolled. During gastroscopy, the remimazolam induction dose was 19.93 ± 2.96 mg (0.2-0.45 mg/kg). Eighteen patients could complete anesthesia with remimazolam alone, and four patients needed propofol to complete anesthesia. The induction time after the injection of remimazolam was 20.8 ± 8.4 s, the gastroscopy time was 5.1 ± 1.3 min, and the anesthesia recovery time was 17.5 ± 5.6 min. The ED50 and the ED95 of remimazolam were 0.362 mg/kg (95% confidence interval [CI]: 0.313-0.455 mg/kg) and 0.464 mg/kg (95% CI: 0.403-2.242 mg/kg), respectively. The vital signs of all patients remained within the predefined acceptable limits. No patients required antagonist rescue.

CONCLUSION

The ED50 and ED95 of remimazolam for adult gastroscopy were 0.362 mg/kg and 0.464 mg/kg, respectively. Additional anesthetics might be required during gastroscopy in some patients.

TRIAL REGISTRATION

The trial was registered. The number is ChiCTR2200057446.

Investigating Deep Sedation With Intravenous Ketamine in Spontaneous Respiration During Pulsed-Field Ablation

OBJECTIVES

The authors report their experience of a protocol for deep sedation with ketamine in spontaneous respiration during the pulsed-field ablation (PFA) of atrial fibrillation (AF).

DESIGN

Observational, prospective, nonrandomized fashion.

SETTING

Single-center hospitalized patients.

PARTICIPANTS

All consecutive patients undergoing PFA of AF.

INTERVENTIONS

Patients undergoing deep sedation with intravenous ketamine.

MEASUREMENTS AND MAIN RESULTS

The authors' sedation protocol involves the intravenous administration of fentanyl (1.5 µg/kg) and midazolam (2 mg) at low doses before local anesthesia with lidocaine. A ketamine adjunct (1 mg/kg) in 5-minute boluses was injected about 5 minutes before the first PFA delivery. The authors enrolled 117 patients (age = 59 ± 10 y, 74.4% males, body mass index = 27.6 ± 5 kg/m2, fluoroscopy time = 24 ± 14 minutes, skin-to-skin time = 80 ± 40 minutes and PFA LA dwell time = 24 ± 7 minutes). By the end of the procedure, pulmonary vein isolation had been achieved in all patients using PFA alone. The mean time under sedation was 54.9 ± 6 minutes, with 92 patients (79%) being sedated for <1 hour. A satisfactory Ramsay Sedation Scale level before ketamine administration was achieved in all patients, except one (80.3% of the patients with rank 3; 18.4% with rank 2). In all procedures, the satisfaction level was found acceptable by both the patient and the primary operator (satisfactory in 98.2% of cases). All patients achieved a Numeric Rating Scale for Pain ≤3 (none or mild). No major procedure or anesthesia-related complications were reported.

CONCLUSION

The authors' standardized sedation protocol with the administration of drugs with rapid onset and pharmacologic offset at low doses was safe and effective, with an optimal degree of patient and operator satisfaction.

Evaluation of a rapid sequence induction technique in dogs with or without rocuronium

OBJECTIVE

To determine, using a rapid sequence induction (RSI) technique, whether rocuronium improves the quality and speed of endotracheal intubation in healthy dogs.

STUDY DESIGN

Randomized, crossover, experimental study.

ANIMALS

Six adult intact male Beagles (12.3 ± 0.4 kg).

METHODS

Dogs were premedicated with intravenous acepromazine (0.03 mg kg-1) and hydromorphone (0.1 mg kg-1). Ten minutes later, anesthesia was induced with intravenous propofol (2 mg kg-1 over 5 seconds), followed by saline (0.06 mL kg-1, CT group) or rocuronium (0.6 mg kg-1, RT group), with orotracheal intubation attempted after 45 seconds. Intubation time (IT) and conditions (IC) were assessed. PaO2, PaCO2, arterial blood pH and serum cortisol were obtained before and after RSI. After endotracheal intubation, saline (0.04 mL kg-1) or sugammadex (4 mg kg-1) were administered intravenously in CT or RT groups, respectively. Spontaneous ventilation restoration was noted.

RESULTS

The IT was 54.3 ± 6.9 (mean ± SD) and 57.8 ± 5.2 seconds for CT and RT, respectively (p = 0.385). All laryngoscopies indicated good IC in both treatment groups. Heart rate was lower in CT group than in RT group (66 ± 16 versus 103 ± 39 beats minute-1, p = 0.016). PaCO2, pH, PaO2 and cortisol did not differ between treatments. Compared with baseline, PaCO2 increased from 47.7 ± 6.2 to 58.8 ± 5.8 (p < 0.001) and pH decreased from 7.35 ± 0.04 to 7.28 ± 0.04 (p = 0.003), independent of treatment. Dogs in both treatment groups returned to spontaneous ventilation within 30 seconds of RSI.

CONCLUSIONS AND CLINICAL RELEVANCE

RSI resulted in respiratory acidosis without hypoxemia or increased cortisol. Rocuronium did not improve IT or IC. Spontaneous ventilation was observed immediately after administering saline or sugammadex. The co-administration of rocuronium showed no clinical benefits over propofol alone in RSI in healthy dogs.

Comparison of three scoring criteria to assess recovery from general anesthesia in the postanesthesia care unit in the indian population

Background

Different discharge criteria are available for shifting patients out from postanesthesia care room following surgery. This study was done to compare the three-scoring system namely traditional time-based criteria, Fast track criteria and modified Aldrete score, in Indian population patients who recover after general anesthesia in postanesthesia care unit (PACU).

Materials and Methods

Three hundred and seventy-five patients scheduled for general anesthesia were included in this study. Induction of anesthesia was done with intravenous (IV) propofol and maintained with sevoflurane inhalation with oxygen and nitrous oxide. Reversal of residual neuromuscular blockade was done with IV neostigmine and glycopyrrolate. Patients were shifted to PACU following tracheal extubation and recovery was assessed using the traditional time-based criteria, fast track criteria, and modified Aldrete score.

Results

As per modified Aldrete score, mean time of shift out is 19 min with median of 15 min and standard deviation of 21.7 min. As per fast-track score, mean time of shift out is 187 min with median of 30 min and standard deviation of 243.7 min. As per the time-based criteria, mean time of shift out is 222 min with median of 240 min and standard deviation of 136.8 min. While using modified Aldrete score, majority of patients had a shorter stay in PACU and faster time to shift out as compared to fast-track criteria and traditional time-based criteria.

Conclusion

Modified Aldrete score when compared to fast-track scoring and time-based criteria shows early recovery and reduces the length of stay in PACU.

The Effect of Anesthetic Agent and Mean Arterial Pressure on Functional Outcome After General Anesthesia for Endovascular Thrombectomy

BACKGROUND

The optimal general anesthetic (GA) technique for stroke patients undergoing endovascular thrombectomy (ET) is unclear. We compared favorable outcomes and mortality in patients receiving propofol or volatile GA during ET and assessed associations between mean arterial pressure (MAP) and outcome.

METHODS

Ninety-three patients with anterior circulation stroke who received propofol or volatile GA during ET between February 2015 and February 2018 were included in this retrospective study. Ninety-day modified Rankin scores were compared and mortality was adjusted for intravenous thrombolysis and diabetes. We performed ordinal logistic regression analyses containing MAP time/exposure thresholds.

RESULTS

There was no difference in the rate of favorable outcome (modified Rankin scores 0-2) in the volatile and propofol groups (48.8% vs. 55.8%, respectively; P =0.5). Ninety-day mortality was lower in patients receiving propofol (11.5%) than in those receiving volatile GA (29.3%) (odds ratio, 0.32; 95% confidence interval, 0.11 to 0.94; P =0.03); this mortality benefit was greater in patients that did not receive intravenous thrombolysis before ET (odds ratio for survival, 6; 95% confidence interval, 1.13 to 31.74). There was no difference in MAP between groups and a (nonsignificant) trend towards the benefit of MAP <90 mm Hg but not <70 mm Hg.

CONCLUSIONS

Favorable outcome rates were similar in stroke patients receiving propofol or volatile GA during ET. Propofol was associated with lower mortality, an effect magnified in patients that did not receive intravenous thrombolysis. MAP time/exposure thresholds were associated with outcome but independent of the anesthetic agent. Our data suggest that a difference in outcome related to an anesthetic agent may exist; this hypothesis needs to be tested in a prospective study.

Hemodynamic impact of increasing time between fentanyl and propofol administration during anesthesia induction: a randomised, clinical trial

BACKGROUND AND OBJECTIVE

Anesthesia induction can produce severe propofol dose-dependent hypotension. Fentanyl coadministration reduces the catecholaminergic response to orotracheal intubation allowing propofol dose reduction. The aim of this study is to determine whether the hemodynamic response is improved by increasing the time between fentanyl and propofol administration and reducing the dose of the latter without increasing the time to achieve optimal hypnosis.

METHODS

After approval by the Research Ethics Committee, patients undergoing non-cardiac surgery with endotracheal intubation were randomized by a computer-generated table into six time-dose groups (1 or 2...minutes/1, 1.5, or 2...mg.kg-1 of propofol). Patients with high bronchoaspiration risk, a difficult airway, hemodynamic instability, or anesthetic allergies were excluded. After giving intravenous fentanyl (2.....g.kg-1), each group received different doses of propofol after 1 or 2...minutes. Noninvasive blood pressure (BP) and heart rate (HR) were measured at pre-induction, pre-intubation, and post-intubation. Time to hypnosis (bispectral index < 60) was also recorded.

RESULTS

Of the 192 recruited patients, 186 completed the study (1...min group n...=...94; 2...min group n...=...92). It was observed that HR and BP decreased after propofol administration and increased after intubation in all groups (p...<...0.0001). In patients over 55 years, the 2 min ... 2 mg.kg-1 group showed the greatest systolic BP reduction (36........12%) at pre-intubation, while the 1...min.........1.5...mg.kg-1 group showed the least hemodynamic alteration between pre- and post-intubation (-4........13%). No significant differences were found in younger patients or in the time to reach hypnosis between the six groups. While no cases of severe bradycardia were recorded, 5,4% of the sample required vasopressors.

CONCLUSION

Increasing the time between the administration of fentanyl and propofol by up to two minutes results in greater hypotension in patients over 55 years.

[Comparison of clinical effects and safety of remidazolam and esketamine for preoperative sedation in children]

OBJECTIVE

To compare the clinical effects and safety of remiazolam and esketamine in preoperative sedation in children.

METHODS

This study was conducted among 61 children (1-4 years old) undergoing elective bilateral tonsillectomy with or without adenoidectomy under general anesthesia from January 2022 to March 2023. The children were randomized into two groups to receive preoperative sedation with intravenous administration of 0.2 mg/kg remidazolam (R group, 30 cases) or 0.5 mg/kg esketamine (S group, 31 cases). The two groups were compared for PSAS score, vital signs (MAP, SpO2, and HR), sedation score, mask acceptance score at induction, sedation onset time, postoperative recovery time, MAP and HR after induction, Ramsay sedation score after awakening, doses of propofol and remifentanil during anesthesia, emergence agitation (EA), postoperative adverse effects and negative postoperative behavioral changes (NPOBCs) on the 7th and 14th days after operation.

RESULTS

The PSAS score, sedation score, mask acceptance score at induction, MAP and HR after induction, Ramsay sedation score after awakening, propofol dose during anesthesia induction, and the incidence of EA and NPOBCs after operation were all similar between the two groups (P > 0.05). Compared with those in S group, the sedation onset time was slightly longer, the recovery time was shorter, and the doses of propofol and remifentanil for anesthesia maintenance was higher (P < 0.05) in R group. Sedation with remidazolam did not cause significant changes in MAP, SpO2 or HR (P > 0.05), while administration of esketamine significantly increased MAP and HR (P < 0.05) without obviously affecting SpO2 (P > 0.05).

CONCLUSION

In children aged 1-4 years, compared with 0.5 mg/kg esketamine, intravenous injection of 0.2 mg/kg remidazolam for preoperative sedation has a slightly longer onset time and is associated with a shorter recovery time and more stable hemodynamics, suggesting its good feasibility and safety.

Effect of Intraoperative Intravenous Lidocaine on Postoperative Delirium in Elderly Patients with Hip Fracture: A Prospective Randomized Controlled Trial

Purpose

This study was performed to evaluate the effects of intraoperative intravenous lidocaine on postoperative delirium in elderly patients with hip fracture.

Patients and methods

In total, 100 elderly patients undergoing hip fracture surgery were randomized to the lidocaine group (Group L) or saline (control) group (Group C). Before anesthetic induction, Group L received lidocaine at 1 mg/kg for more than 10 minutes followed by continuous infusion at 1.5 mg/kg/h until the end of surgery. Group C received normal saline, and the injection methods were consistent with those in Group L. General anesthesia was induced with propofol, sufentanil, and cis-atracurium. Anesthesia was maintained by propofol and remifentanil. The primary outcome was the incidence of postoperative delirium in the first 7 postoperative days. The secondary outcomes included the severity of delirium, onset and duration of delirium, emergence agitation, adverse events, total propofol dose, intraoperative opioid dosage, length of post-anesthesia care unit stay, extubation time, and patient satisfaction with postoperative pain management.

Results

All 100 patients completed the study. The incidence of postoperative delirium was lower in Group L than in Group C (14% vs 36%, P = 0.011). The delirium severity scores were lower in Group L (3 [3-4]) than in Group C (4 [4-5]) (P = 0.017). In addition, the incidences of hypertension, tachycardia, and emergence agitation were significantly lower in Group L than in Group C. No cases of local anesthetic toxicity occurred in either group.

Conclusion

Patients received lidocaine at 1 mg/kg for more than 10 minutes followed by continuous infusion at 1.5 mg/kg/h until the end of surgery, which can reduce the incidence of postoperative delirium in elderly patients undergoing hip fracture. In addition, the used regimen of lidocaine would not increase the risk of local anesthetic toxicity.

Esketamine Combined with Propofol TCI versus Propofol TCI for Deep Sedation during Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration: A Prospective, Randomized, and Controlled Trial

Background

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is an invasive procedure that required deep sedation to suppress coughing and body movements. Deep sedation, on the other hand, has been shown to cause respiratory and circulatory depression, especially when the airway is shared with the endoscopist. Esketamine is a novel sedative and analgesic with little respiratory inhibition that appears to be an appropriate adjuvant in propofol sedation for EBUS-TBNA. We compared the efficacy and safety of esketamine combined with propofol target-controlled infusion (TCI) and propofol TCI for deep sedation in EBUS-TBNA.

Methods

The study included 135 patients with ASA II-III undergoing EBUS-TBNA. They were randomly divided into two groups (group E and group P). Both groups received midazolam (0.01-0.03 mg/kg) and oxycodone (0.07-0.08 mg/kg). Then, patients in group E received 0.3 mg/kg esketamine, propofol TCI, and 0.2 mg·kg-1·h-1 esketamine for sedative maintenance. Patients in group P received only propofol TCI. The primary outcome was the dose of 1% lidocaine administrated by the endoscopist and the times of lidocaine sprays. Secondary outcome indicators were cough score, propofol dosage, patient satisfaction, endoscopist satisfaction, the incidence of sedation-related adverse effects and side effects, and recovery time.

Results

Patients in group E were given significantly less lidocaine (4.36 ml/h (2.67-6.00) vs 6.00 ml/h (4.36-7.20), P < 0.001) and less spraying frequency (2.18 times/h (1.33-3.00) vs 3.00 times/h (2.18-3.60), P < 0.001) than group P. There was a statistically significant difference in cough score between the two groups (group E 2 (0-4) vs group P 3 (2-4), P=0.03). Also, mean arterial pressure (MAP) was higher in group E in the 30th min (T5, 84.10 ± 12.91 mmHg versus 79.04 ± 10.01 mmHg, P=0.012) and 40th min (T6, 87.72 ± 15.55 mmHg versus 82.14 ± 10.51 mmHg, P=0.026). There were no significant differences between the two groups in terms of sedation-related adverse events and side effects, recovery time, endoscopist satisfaction, and patient satisfaction.

Conclusions

In patients with ASA II-III, esketamine as an adjuvant in combination with propofol TCI deep sedation for EBUS-TBNA can improve the sedation effect, reduce coughing reaction during the procedure, and obtain more stable blood pressure. No reduction in the occurrence of sedation-related side effects was observed. This trial is registered with ChiCTR2200061124.

Risk factors for pharyngalgia and xerostomia undergoing supraglottic jet oxygenation and ventilation in gastrointestinal endoscopy: a retrospective study

Supraglottic jet oxygenation/ventilation (SJOV) can reduce hypoxemia in sedated endoscopy but may increase minor side effects like pharyngalgia and xerostomia. This study aimed to identify risk factors for pharyngalgia/xerostomia with SJOV during gastrointestinal endoscopy. From January 1 to December 31, 2021, 5313 patients with propofol sedation and SJOV underwent gastrointestinal endoscopy or removal of gastrointestinal polyps was analyzed retrospectively. Data included patient characteristics, operation details, postoperative adverse events, and potential risk factors for postoperative adverse events. Parameters considered as potential risk factors were identified based on study results published previously and based on the researcher's idea and clinical experience. The patient factors and the incidence of pharyngalgia/xerostomia at 30 min post-procedure were assessed. Descriptive statistics were calculated using SPSS software. Evaluation potential risk factors using univariate and multivariate logistic regression. Pharyngalgia/xerostomia occurred in 18.7% of patients at 30 min after procedure. A multivariable analysis showed that procedure time and pharyngalgia/xerostomia within 2 weeks were independent risk factors. Procedure time had the strongest association with postoperative pharyngalgia/xerostomia (OR, 8.09 [95% CI, 4.197-6.312]). No factors were significantly associated with hypoxemia risk (1.7% incidence). There were no barotrauma or other serious morbidity or mortality. Procedure duration and recent pharyngalgia/xerostomia increased risk of pharyngalgia/xerostomia with SJOV during endoscopy. Limiting SJOV duration may reduce side effects in susceptible patients. No predictors of hypoxemia were identified.

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.

Noninvasive Cardiac Output Monitoring (NICOM) in the Critically Ill Patient Undergoing Endotracheal Intubation: A Prospective Observational Study

Background: Cardiovascular instability occurring during endotracheal intubation (ETI) in the critically ill is a commonly recognized phenomenon. However, this complication has not been evaluated in terms of the physiological cause (ie, decreased preload, contractility, or afterload) leading to the instability. Thus, the aim of the current investigation was to describe the hemodynamics occurring during ETI with noninvasive physiologic monitoring and to collect preliminary data on the hemodynamic effects of induction agents and positive pressure ventilation. Methods: A multicenter prospective study enrolling adult (≥18 years) critically ill patients undergoing ETI with noninvasive cardiac output monitoring in a medical/surgical intensive care unit from June 2018 to May 2019 was conducted. This study used the Cheetah Medical noninvasive cardiac output monitor to collect hemodynamic data during the peri-intubation period. Additional data collected included baseline characteristics such as illness severity, peri-intubation pharmacologic administration, and mechanical ventilation settings. Results: From the original 27 patients, only 19 (70%) patients had complete data and were included in the final analysis. Propofol was the most common sedative 8 (42%) followed by ketamine 6 (32%) and etomidate 5 (26%). Patients given propofol demonstrated a decrease in total peripheral resistance index (delta change [dynes × s/cm-5/m2]: -2.7 ± 778.2) but stabilization in cardiac index (delta change (L/min/m2]: 0.1 ± 1.5) while etomidate and ketamine demonstrated increases in total peripheral resistance index (etomidate delta change [dynes × s/cm-5/m2]: 302.1 ± 414.3; ketamine delta change [dynes × s/cm-5/m2]: 278.7 ± 418.9) but only etomidate resulted in a decrease in cardiac index (delta change [L/min/m2]: -0.3 ± 0.5). Positive pressure ventilation resulted in minimal changes to hemodynamics during ETI. Conclusions: The current study demonstrates that although propofol administration leads to a decrease in total peripheral resistance index, cardiac index is maintained while etomidate leads to a decrease in cardiac index with both etomidate and ketamine increasing total peripheral resistance index. These hemodynamic profiles are minimally affected by positive pressure ventilation. Study registration: ClinicalTrials.gov ID, NCT03525743.

Prevention and treatment of traumatic brain injury-related delirium: a systematic review

BACKGROUND

Our systematic review examines the effectiveness and safety of non-pharmacologic and pharmacologic interventions in preventing or treating traumatic brain injury (TBI)-related delirium in acute care.

METHODS

We searched four electronic databases (MEDLINE, EMBASE, CENTRAL/CDSR, and PsycINFO) to identify randomized controlled trials (RCTs), quasi-experimental, and observational studies. Eligible studies included adults with TBI, at least one comparator group, delirium as an outcome and took place in acute care. Two reviewers independently completed all study screening, data abstraction, and risk of bias assessment using the Cochrane risk of bias 2 tool for RCTs or risk of bias in non-randomized studies-of interventions tool for observational studies. We implemented the PROGRESS-Plus framework to describe social determinants of health (SDoH) reporting.

RESULTS

We identified 20,022 citations, reviewed 301 in full text, and included eight studies in the descriptive synthesis. The mean age of study participants ranged from 32 to 62 years. 12.5% of included studies reported SDoH. Included studies had moderate-to-high risk of bias. Studies compared reorientation programs and an intervention bundle to usual care, but these interventions were not better than usual care in treating TBI-related delirium. Individual studies found that rosuvastatin and aripiprazole were more efficacious than placebo, and dexmedetomidine was more efficacious than propofol and haloperidol for preventing TBI-related delirium. No studies reported safety as the primary outcome.

CONCLUSIONS

We identified efficacious pharmacologic interventions for preventing TBI-related delirium, but these studies were at moderate-to-high risk of bias, which limits our confidence in these findings. Future studies should incorporate safety outcomes, and a diverse study population, including older adults.

Comparison of the effects of dexmedetomidine and propofol on the cardiovascular autonomic nervous system during spinal anesthesia: preliminary randomized controlled observational study

Spinal anesthesia induces sympatholysis and is usually combined with dexmedetomidine or propofol which induce different hemodynamic changes. The purpose of this study was to compare the effect on autonomic nervous system between dexmedetomidine and propofol combined with spinal anesthesia. Patients aged 20-65 undergoing elective surgery under spinal anesthesia were randomly assigned to dexmedetomidine or propofol group. Heart rate variability (HRV) and hemodynamic variables were measured at four time points: T0, baseline; T1, 10 min after spinal anesthesia; T2, 10 min after sedative administration; and T3, 20 min after sedative administration. In 59 patients, dexmedetomidine and propofol groups had significantly different hemodynamic changes over time (time × group effect P < 0.001). The dexmedetomidine group had slower heart rate at T2 (P = 0.001) and higher blood pressures at T2 and T3 (P < 0.001) than the propofol group. Overall HRV dynamics showed a significant change over time from T0 to T3, but both groups exhibited similar trends. Compared to the baseline data within the group, the low frequency (LF) decreased in both groups but the decrease occurred at T2 in the propofol group and at T3 in the dexmedetomidine group. The high frequency (HF) increased at T2 and T3 only in the dexmedetomidine group. The LF/HF ratio decreased in the dexmedetomidine group at T3. Dexmedetomidine showed slower heart rate and higher blood pressure than propofol when combined with spinal anesthesia, however, dexmedetomidine and propofol exhibited similar trends in HRV dynamics. Compared with the baseline within each group, both agents decreased LF, but only dexmedetomidine increased HF and decreased in the LF/HF ratio significantly.

Direct and continuous dosing of propofol can saturate Ex vivo ECMO circuit to improve propofol recovery

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) is a cardiopulmonary bypass device that provides life-saving complete respiratory and cardiac support in patients with cardiorespiratory failure. The majority of drugs prescribed to patients on ECMO lack a dosing strategy optimized for ECMO patients. Several studies demonstrated that dosing is different in this population because the ECMO circuit components can adsorb drugs and affect drug exposure substantially. Saturation of ECMO circuit components by drug disposition has been posited but has not been proven. In this study, we have attempted to determine if propofol adsorption is saturable in ex vivo ECMO circuits.

METHODS

We injected ex vivo ECMO circuits with propofol, a drug that is highly adsorbed to the ECMO circuit components. Propofol was injected as a bolus dose (50 μg/mL) and a continuous infusion dose (6 mg/h) to investigate the saturation of the ECMO circuit.

RESULTS

After the bolus dose, only 27% of propofol was recovered after 30 minutes which is as expected. However, >80% propofol was recovered after the infusion dose which persisted even when the infusion dose was discontinued.

CONCLUSION

Our results suggest that if ECMO circuits are dosed directly with propofol, drug adsorption can be eliminated as a cause for altered drug exposure. Field of Research: Artificial Lung/ECMO.

Cannabis Users Require More Anesthetic Agents for General Anesthesia in Ambulatory Oral and Maxillofacial Surgery Procedures

BACKGROUND

The use of cannabis in the general population has steadily increased over recent years and there is limited literature regarding the anesthetic implications of chronic cannabis use, particularly in the setting of outpatient anesthesia.

PURPOSE

To determine whether chronic cannabis users undergoing deep sedation or general anesthesia during ambulatory procedures require more anesthetic agents than nonusers.

STUDY DESIGN, SETTING, AND SAMPLE

A retrospective cohort study of subjects undergoing deep sedation or general anesthesia at the Oklahoma University Oral and Maxillofacial Surgery Clinic from January to December 2022 was performed. The inclusion criteria were duration of anesthetic procedure between 15 to 40 minutes, use of propofol, fentanyl, ketamine, and midazolam, and extraction of at least 2 teeth. The exclusion criterion was patients undergoing adjunctive procedures other than extractions during sedation.

PREDICTOR VARIABLE

Cannabis use status was grouped as users and nonusers. A user was defined as a subject who self-reported any regular use of cannabis.

OUTCOME VARIABLE

The primary outcome variable was the amount of intravenous anesthetic agents administered. Secondary outcome variables included the length of the procedure and the number of teeth extracted.

COVARIATES

Age, sex, and the senior-most resident involved in the sedation.

ANALYSES

IBM SPSS was utilized to perform descriptive statistics, paired t-tests, ANOVA, and multivariate linear regression. A level of significance of 5% (P < .05) was used for all analyses.

RESULTS

Four hundred and ninety nine subjects were identified, 189 met the inclusion criteria, and 57 reported using cannabis. The mean age of nonusers was 28.2 ± 7.8 years and that of users was 26.6 ± 6.4 years (P = .09). Females represented 71.9% of nonusers and 72.7% of users. Cannabis users received significantly more propofol (117.5 mg ± 71.3 vs 152.5 mg ± 101.8; P = .004), midazolam (4.7 mg ± 1.0 vs 5.1 mg ± 1.5; P = .01), ketamine (40.2 mg ± 15.7 vs 46.1 mg ± 16.9; P = .01), and fentanyl (75.2 μg ± 26.3 vs 88.6 μg ± 32.8; P = .002) than nonusers, despite extracting a similar number of teeth (4.5 ± 3.1 vs 4.4 ± 3.5; P = .37) in a similar amount of time (25.5 ± 7.3 vs 27.3 ± 7.8; P = .06).

CONCLUSION AND RELEVANCE

Cannabis users required more propofol, midazolam, ketamine, and fentanyl than non-cannabis users during outpatient oral and maxillofacial surgery procedures.

Increasing the aqueous solubility of the anesthetic propofol through wormlike micelle formation

Propofol, a phenol derivative, is commonly employed as an intravenous anesthetic during clinical procedures, formulated as an oil/water emulsion due to its poor solubility in water. The stability limitations associated with emulsions have prompted research efforts towards developing aqueous formulations of propofol. In this work, we investigate the solubility enhancement of propofol in anionic and cationic surfactants. Our findings reveal that the solubility of propofol can increase significantly, up to 100-fold, depending on the nature of the micellar aggregate, as observed for alkylammonium halogenates CnTAB (for n = 12, 14 and 16), contrasting with the lower solubility with SDS. Interestingly, C14TAB and C16TAB demonstrate significantly higher solubility than C12TAB. This was attributed to the formation of wormlike micelles, in which the propofol molecules are positioned between the cationic heads of the surfactant molecules, changing the micellar curvature and the morphology of the aggregate. Therefore, the aromatic molecules in the micellar environment can be partitioned into the micellar cores and their palisades. Regarding C12TAB, the alkyl chain is too short to form wormlike micelles, thus, concentrating propofol molecules mainly into the micellar core, and consequently, leading to their aggregation. Solubility diagrams of propofol were constructed in conjunction with different surfactants. The systems exhibiting viscoelastic behavior, indicative of wormlike micelle formation, were further investigated using rheology. Additionally, the fluorescent properties of propofol enabled the examination of the anesthetic molecule within diverse micellar environments.

Practice-Pattern Variation in Sedation of Neurotrauma Patients in the Intensive Care Unit: An International Survey

Background: Analgo-sedation plays an important role during intensive care management of traumatic brain injury (TBI) patients, however, limited evidence is available to guide practice. We sought to quantify practice-pattern variation in neurotrauma sedation management, surveying an international sample of providers. Methods: An electronic survey consisting of 56 questions was distributed internationally to neurocritical care providers utilizing the Research Electronic Data Capture platform. Descriptive statistics were used to quantitatively describe and summarize the responses. Results: Ninety-five providers from 37 countries responded. 56.8% were attending physicians with primary medical training most commonly in intensive care medicine (68.4%) and anesthesiology (26.3%). Institutional sedation guidelines for TBI patients were available in 43.2%. Most common sedative agents for induction and maintenance, respectively, were propofol (87.5% and 88.4%), opioids (60.2% and 70.5%), and benzodiazepines (53.4% and 68.4%). Induction and maintenance sedatives, respectively, are mostly chosen according to provider preference (68.2% and 58.9%) rather than institutional guidelines (26.1% and 35.8%). Sedation duration for patients with intracranial hypertension ranged from 24 h to 14 days. Neurological wake-up testing (NWT) was routinely performed in 70.5%. The most common NWT frequency was every 24 h (47.8%), although 20.8% performed NWT at least every 2 h. Richmond Agitation and Sedation Scale targets varied from deep sedation (34.7%) to alert and calm (17.9%). Conclusions: Among critically ill TBI patients, sedation management follows provider preference rather than institutional sedation guidelines. Wide practice-pattern variation exists for the type, duration, and target of sedative management and NWT performance. Future comparative effectiveness research investigating these differences may help optimize sedation strategies to promote recovery.

Efficacy of ultrasound guided superior laryngeal nerve block on sedation for delayed extubation in maxillofacial surgery with free flap reconstruction

OBJECTIVE

Superior laryngeal nerve block (SLNB) is a regional anesthesia technique for addressing airway response. However, SLNB on the efficacy of sedation in patients with delayed extubation is unknown, particularly for maxillofacial surgery (MS). The aim of the study was to assess whether ultrasound guided (UG) SLNB reduces the incidence of moderate to severe cough for delayed extubation in MS with free flap reconstruction.

METHODS

60 patients were randomly assigned to the GEA group (control group) and the SLNB group (UG-SLNB postoperatively, study group). During the initial two postoperative hours, the incidence of moderate and severe cough, agitation, and the number of patients requiring rescue propofol and flurbiprofen were recorded. Additionally, the time spent under the target level of sedation, postoperative hemodynamics, and the total does of propofol during the postoperative 24 h were recorded.

RESULTS

The data showed the SLNB group had a significantly lower incidence of moderate to severe cough and agitation (p < 0.05), and a longer sedation time (p < 0.05). The number of patients required rescue propofol and flurbiprofen, as well as the hemodynamic changes, were significantly different between the two groups (p < 0.05).

CONCLUSION

The use of UG-SLNB is associated with reduced incidence of postoperative cough. Moreover, SLNB can enhance the efficacy of postoperative sedation with need of fewer agents postoperatively.

CLINICAL TRIAL REGISTRATION

ChiCTR2000039982.

Sedation with Propofol and Propofol-Ketamine (Ketofol) in Flexible Bronchoscopy: A Randomized, Double-Blind, Prospective Study

BACKGROUND

The flexible bronchoscopy procedure, which is performed in awake conditions or under local anesthesia, is a difficult and complicated procedure for patients and physicians. Propofol is a fast-acting sedative-hypnotic anesthetic with a rapid return. Ketamine hydrochloride is a fast-acting general anesthetic producing an anesthetic state characterized by deep analgesia, normal pharyngeal, and laryngeal reflexes.

MATERIALS AND METHOD

The study was planned in a randomized, prospective, and double-blind design. The drug(s) administered by the anesthesiologist was not known to the bronchoscopist and the patient. A total of 64 cases were included in the study (34/propofol, 30/ketamine-propofol (ketofol) group). Group propofol received 0.1 mL/kg propofol, and group ketofol received 0.1 mL/kg ketofol intravenously over approximately 30 seconds. Vital signs, non-invasive blood pressure, peripheral oxygen saturation, and pulse values of all cases were measured three times and were recorded just before the start of the procedure, after entering the trachea, and after the procedure was terminated. The Visual Analogue Scale (VAS) and The Ramsay scoring were additionally used in the present study.

RESULTS

Statistically significant differences were detected between the groups in terms of blood pressure and heart rates. Statistically significant differences were detected between the two groups according to The VAS scoring and additional dose requirement.

CONCLUSION

It must be noted that flexible bronchoscopy procedures, which are performed with local anesthesia by both the patient and the physician with a high degree of difficulty, especially combined drugs to be applied with anesthesia support, are more effective/comfortable/reliable, and have fewer complications and higher tolerability if there are no contraindications.

Safety of endoscopist-guided sedation in a low-risk collective

INTRODUCTION

 Worldwide, gastrointestinal endoscopies are predominantly performed under sedation. National and international guidelines and recommendations contain very different specifications for the use of sedation in gastrointestinal endoscopy. These differences come from specific requirements for staffing during endoscopy.

AIM

 The aim of the study is to evaluate whether endoscopist-guided sedation without additional sedation assistance is not inferior to endoscopist-guided sedation with additional sedation assistance with respect to the rate of sedation-associated complications in a defined low-risk population (low-risk procedure and low-risk patient).

METHODS

 Prospective, multicenter, randomized study.

RESULTS

 27 German study centers participated in the study. A total of 30 569 endoscopies were recorded during the study period from 1.8.2015 to 10.3.2020. The final data analysis included 28 673 examinations (64.1 % esophagosgastroduodenoscopies and 35.9 % colonoscopies). In 307 (1.1 %) examinations, 322 sedation-associated complications occurred. Of these, 321 (1.1 %) were minor complications and one (0.003 %) was a major complication. There was no statistically significant difference in the frequency of sedation-associated complications between endoscopist-guided sedation with versus without additional sedation assistance. Within the legal framework, a "shadow" sedation assistant was present in the study group without sedation assistance. This assistant intervened because of sedation-associated complications in 101 (0.7 %) of the endoscopies.

CONCLUSION

 The study documents the safety of propofol-based endoscopist-guided sedation in a low-risk population. In 98.9 % of all endoscopies, no sedation-associated complication occurred or it was so minimal that no intervention (e. g., increase of oxygen supply) was necessary. The study cannot answer to what extent a serious complication was avoided by the active intervention of the "shadow" sedation assistance in the group without sedation assistance.The study proves in a randomized, prospective design that sedation in low-risk endoscopy (low-risk patient, low-risk procedure) can be performed as endoscopist-guided sedation without additional sedation assistance, without demonstrably accepting a reduction in safety.

Impact of Propofol-based Total Intravenous Anesthesia Versus Inhalation Anesthesia on Long-term Survival After Cancer Surgery in a Nationwide Cohort

OBJECTIVE

To compare the impact of propofol-based total intravenous anesthesia (TIVA) versus inhalational anesthesia (IA) on the overall survival following cancer surgery.

BACKGROUND

The association between intraoperative anesthetics and patients' long-term outcomes following cancer surgery remains controversial.

METHODS

This retrospective cohort study used nationwide data from the Korean National Health Insurance Service. Adult patients who underwent cancer resection surgery (breast, gastric, lung, liver, kidney, colorectal, pancreatic, esophageal, and bladder cancer) under general anesthesia between January 2007 and December 2016 were included. Patients were divided into propofol-based TIVA or IA groups according to the type of anesthesia received. A total of 312,985 patients (37,063 in the propofol-based TIVA group and 275,922 patients in the IA group) were eligible for analysis. The primary outcome was the comparison of overall survival following surgery between the groups in each cancer type. We compared the all-cause mortality between the 2 groups, stratified by cancer type using time-dependent Cox regression after propensity score-based inverse probability of treatment weighting. We further examined the comparison of overall survival in a meta-analysis using data from our study and previously published data comparing propofol-based TIVA with IA after cancer surgery.

RESULTS

The number of deaths in the propofol-based TIVA and IA groups was 5037 (13.6%) and 45,904 (16.6%), respectively; the median (interquartile range) follow-up duration was 1192 (637-2011) days. Multivariable Cox proportional hazards regression analysis revealed no significant association between the type of general anesthesia and overall survival after cancer surgery in the weighted cohort for each cancer type (all P >0.05) and for total population [adjusted hazard ratio (HR): 0.98, 95% confidence interval (CI): 0.93-1.04]. In a meta-analysis, single-center studies showed higher overall survival in the TIVA group than in the IA group (pooled adjusted HR: 0.65, 95% CI: 0.47-0.91, P =0.01), while multicenter studies showed insignificant pooled adjusted HRs (pooled adjusted HR: 1.05, 95% CI: 0.82-1.33, P =0.71).

CONCLUSIONS

There is no association between the type of general anesthesia used during cancer surgery and postoperative overall, 1-, and 5-year survival.