Deep sedation using propofol target-controlled infusion for gastrointestinal endoscopic procedures: a retrospective cohort study

Nasal continuous positive pressure versus simple face mask oxygenation for adult obese and obstructive sleep apnea patients undergoing colonoscopy under propofol-based general anesthesia without tracheal intubation: A randomized controlled trial

STUDY OBJECTIVE

To determine if a nasal positive airway pressure (nasal CPAP) mask would decrease the number of hypoxemic events in obese and obstructive sleep apnea patients undergoing colonoscopy.

DESIGN

Single-center prospective randomized controlled trial.

SETTING

Tertiary academic center.

PATIENTS

We enrolled 109 patients with diagnosis of obesity and/or obstructive sleep apnea scheduled to undergo colonoscopy under propofol general anesthesia without planned tracheal intubation.

INTERVENTION

Patients were randomly allocated (1:1 ratio) to receive supplementary oxygen at a flow of 10 L/min, either through a nasal CPAP or a simple facemask.

MEASUREMENTS

The primary endpoint was the difference in the mean percentage of time spent with oxygen saturation below 90% between the two groups. Secondary outcomes included the need for airway maneuvers/interventions, average SpO2 during the case, duration and severity of oxygen desaturation, incidence and duration of procedural interruptions, and satisfaction and tolerance scores.

MAIN RESULTS

54 were allocated to the simple face mask and 55 to the nasal CPAP mask arms, respectively. A total of 6 patients experienced a hypoxemic event. Among these patients, the difference in the percentage of time spent with oxygen saturation below 90% was not clinically relevant (p = 1.0). However, patients in the nasal CPAP group required less chin lift (20% vs. 42.6%; p = 0.01) and oral cannula insertion (12.7% vs.29.6%; p = 0.03). The percentage of patients with at least one airway maneuver was higher in the simple face mask arm (68.5% vs. 41.8%; p = 0.005). Patient tolerance to device score was lower in the nasal CPAP group (8.85 vs. 9.56; p = 0.003).

CONCLUSIONS

A nasal CPAP did not prevent hypoxemia and should not be used routinely for colonoscopy in obese or OSA patients if a simple face mask is an alternative therapy. However, potential advantages of its use include fewer airway maneuvers or interventions, which may be desirable in certain clinical settings.

TRIAL REGISTRATION

Clinicaltrials.gov, identifier: NCT05175573.

Remimazolam versus propofol in combination with esketamine for surgical abortion: A double-blind randomized controlled trial

Remimazolam is a new benzodiazepine with a short half-life, good efficacy, and safety profiles in general anesthesia. Combining esketamine with propofol (P + E) could reduce propofol consumption and injection pain. It is, however, unclear if a low dose of remimazolam co-administrated with esketamine (R + E) is comparable to the increasingly used P + E for surgical abortion with general anesthetic. We conducted a double-blind randomized controlled trial to compare the efficacy and safety of R + E and P + E. Two hundred patients scheduled for a surgical abortion were randomized to receive remimazolam 0.3 mg/kg plus esketamine 0.3 mg/kg (R + E), and propofol 2 mg/kg plus esketamine 0.3 mg/kg (P + E). Sedative effectiveness was evaluated by measuring the time to lose consciousness (LOC), recovery time, and successful sedation rate. Safety was assessed by hemodynamics and adverse events during and postoperation. The time to LOC and recovery time in R + E was 5 s shorter and 1 min longer than that in P + E, respectively (both p < 0.001). Success sedation rate did not differ between groups (p = 0.73). Bradycardia incidence and injection site pain were less frequent in the R + E group than that in the P + E group. More rash was observed in the R + E group compared with the P + E group (32% vs. 5%, p < 0.001), but all were mild (only chest rash) and resolved subsequently. Low dose of remimazolam when combined with esketamine has favorable profiles with rapid onset and recovery, but mild hemodynamic side effects and adverse events. It can be used as an alternative for surgical abortion with general anesthetic.

ED50 and ED95 of Propofol Combined with Different Doses of Intravenous Lidocaine for First-Trimester Uterine Aspiration: A Prospective Dose-Finding Study Using Up-and-Down Sequential Allocation Method

Purpose

This study aimed to test the effect of different doses of intravenous lidocaine on the median effective dose (ED50) and 95% effective dose (ED95) of propofol-induction dose and identify the optimal dose.

Patients and Methods

Patients undergoing first-trimester uterine aspiration were screened and randomly enrolled into the following groups: saline (L₀), 0.5 mg/kg lidocaine (L_0.5), 1.0 mg/kg lidocaine (L_1.0), and 1.5 mg/kg lidocaine (L_1.5). Anesthesia was induced with 1.0 µg/kg fentanyl. Prepared lidocaine or saline solution was injected later according to allocation, followed by propofol. The dose of propofol for each patient was determined using the up-and-down sequential study design. The primary end point was the ED50 and ED95 of the propofol-induction dose. The total propofol doses, awakening time, and adverse events were recorded.

Results

The ED50 (95% confidence interval) of propofol was significantly lower in groups L_1.0 and L_1.5 than group L₀ (1.6 [1.5–1.7] mg/kg and 1.8 [1.6–1.9] mg/kg, versus 2.4 [2.3–2.5] mg/kg, respectively; p<0.001). There was no significant difference in ED50 between groups L_1.0 and L_1.5 (p>0.05). However, surprisingly, the ED50 was significantly higher in group L_0.5 than L₀ (2.8 [2.6–3.0] mg/kg vs 2.4 [2.3–2.5] mg/kg; p<0.05). The total doses of propofol in groups L_1.0 and L_1.5 were lower than those in groups L₀ and L_0.5 (p<0.05). The systolic blood pressure (SBP) decline after anesthesia induction in group L_0.5 was greater than that in group L₀ (p<0.01). The incidence of respiratory depression in group L_0.5 was greater than that in groups L₀ and L_1.0 (p<0.05).

Conclusion

In patients who underwent first-trimester uterine aspiration, intravenous lidocaine 1.0 mg/kg prior to propofol injection significantly reduced the ED50 of propofol induction dose without severe side effects, equivalent to the effect of 1.5 mg/kg dose. We recommend 1.0 mg/kg as the optimal dose.

Comparison of three sedation models for same-day painless bidirectional endoscopy: A multicenter randomized controlled trial

BACKGROUND AND AIM

We investigated the most beneficial propofol sedation model for same-day painless bidirectional endoscopy (BDE).

METHODS

Asymptomatic participants scheduled for same-day painless BDE examination from October 2020 to September 2021 were randomized to three groups: sedated esophagogastroduodenoscopy followed by unsedated colonoscopy (Group A); sedated esophagogastroduodenoscopy followed by sedated colonoscopy (Group B); and sedated esophagogastroduodenoscopy followed by sedated insertion colonoscopy (Group C). Patient discomfort, colonoscopy performance, doses of propofol, cardiovascular stress, anesthesia resuscitation, and sedation-related adverse events were evaluated.

RESULTS

A total of 3200 participants were analyzed. Baseline demographics, patient discomfort, cecal intubation rate, adenoma detection rate and sedation-related adverse events were similar in the three groups. Propofol dose was the lowest in Group A (137.65 ± 36.865 mg) compared with Group B (177.71 ± 40.112 mg, P < 0.05) and Group C (161.63 ± 31.789 mg, P < 0.05). Decline in vital signs was most obvious in Group B during the procedure (P < 0.05). Recovery time was the shortest in Group A (5.01 ± 1.404 min) compared with Group B (9.51 ± 2.870 min, P < 0.05) and Group C (5.83 ± 2.594 min, P < 0.05); discharge time was the shortest in Group A (3.53 ± 1.685 min) compared with Group B (11.29 ± 5.172 min, P < 0.05) and Group C (6.47 ± 2.338 min, P < 0.05). Adenomas per positive patient of Group A (2.29 ± 1.055) and Group C (2.28 ± 0.931) were more than that in Group B (2.11 ± 0.946, P < 0.05).

CONCLUSIONS

Sedated esophagogastroduodenoscopy followed by unsedated colonoscopy is the superior model for same-day painless BDE with the benefits of satisfactory patient comfort, reduced sedation dose, less cardiovascular stress, faster recovery, shorter discharge time and high colonoscopy quality.

Efficacy and Safety of Deep Sedation and Anaesthesia for Complex Endoscopic Procedures—A Narrative Review

Propofol sedation for advanced endoscopic procedures is a widespread technique at present, which generates controversy worldwide when anaesthetic or non-anaesthetic personnel administer this form of sedation. There is some evidence for safe administered propofol sedation by non-anaesthetic personnel in patients undergoing endoscopy procedures, but there are only few randomised trials addressing the safety and efficacy of propofol in patients undergoing advanced procedures. A serious possible consequence of propofol sedation is the rapid and unpredictable progression from deep sedation to general anaesthesia mostly when elderly and frail patients are involved in the diagnosis or treatment of various neoplasia. This situation requires rescue measures with skilled airway management. The aim of this paper is to review the safety and efficacy aspects of sedation techniques, with special reference to propofol administration covering the whole patient journey, including preassessment, sedation options and discharge when advanced endoscopic procedures are performed.

Incidence and Risk Factors for Hypoxia in Deep Sedation of Propofol for Artificial Abortion Patients

Background

Respiratory depression is a life-threatening adverse effect of deep sedation. This study aimed to investigate the factors related to hypoxia caused by propofol during intravenous anesthesia.

Methods

Three hundred and eight patients who underwent painless artificial abortion in the outpatient department of Shanghai Tenth People’s Hospital between November 1, 2019 and June 30, 2020 were divided into two groups according to whether the patients experienced hypoxia (SpO₂ < 95%). Preoperative anxiety assessments, anesthesia process, and operation-related information of the two groups were analyzed. The univariate analysis results were further incorporated into logistic regression analysis for multivariate analysis to determine the independent risk factors affecting hypoxia.

Results

Univariate analysis revealed that body mass index (BMI) (21.80 ± 2.94 vs. 21.01 ± 2.39; P = 0.038, 95% confidence interval (CI) = [−1.54, −0.04]), propofol dose (15.83 ± 3.21 vs. 14.39 ± 3.01; P = 0.002, CI = [−2.34, −0.53]), menopausal days (49.64 ± 6.03 vs. 52.14 ± 5.73; P = 0.004, CI = [0.79, 4.21]), State Anxiety Inventory score (51.19 ± 7.55 vs. 44.49 ± 8.96; P < 0.001, CI = [−9.26, −4.15]), and Self-rating Anxiety Scale score (45.86 ± 9.48 vs. 42.45 ± 9.88; P = 0.021, CI = [−6.30, −0.53]) were statistically significant risk factors for hypoxia during the operation. Logistic regression analysis showed that propofol dosage, menopausal days, and State Anxiety Inventory score were independent risk factors for hypoxia.

Conclusion

Patient anxiety affects the incidence of hypoxia when undergoing deep intravenous anesthesia with propofol. We can further speculate that alleviating patient anxiety can reduce the incidence of hypoxia.

Clinical Trial Registration

[http://www.chictr.org.cn], identifier [ChiCTR2000032167].

ED50 and ED95 of propofol combined with different doses of esketamine for children undergoing upper gastrointestinal endoscopy: A prospective dose-finding study using up-and-down sequential allocation method

WHAT IS KNOWN AND OBJECTIVE

Propofol and esketamine are routine anaesthetics used in sedation or general anaesthesia for paediatric procedures. Coadministration could reduce the dose of either propofol or esketamine required and lower the incidence of drug-related adverse events. We designed a four-arm randomized controlled trial in children undergoing diagnostic upper gastrointestinal endoscopy to investigate the dose of propofol with different doses of esketamine inducing appropriate depth of anaesthesia in 50% patients (median effective dose, ED₅₀ ).

METHODS

After getting the approval of the research ethics committee and informed consent, 92 paediatric patients planning for upper gastrointestinal endoscopy were divided into four groups randomly: esketamine 0, 0.25, 0.5 and 1 mg/kg groups (n = 23/group). Propofol doses followed the Dixon and Massey up-and-down method with different starting and interval doses between groups. During the first attempt of endoscope insertion, if patients' reactions prevented the insertion, it would be considered as a failure. The awakening time, total propofol doses, as well as the perioperative and post-procedure adverse events were evaluated and recorded for each patient.

RESULTS AND DISCUSSION

The ED₅₀ (median, 95% confidence interval) of propofol was significantly greater in esketamine 0 and 0.25 mg/kg groups in comparison with the esketamine 0.5 and 1 mg/kg groups (4.1 [3.3-4.9]; 3.1 [2.5-3.8] mg/kg vs. 1.8 [1.1-2.4]; 0.8 [0.2-1.3] mg/kg, respectively, p < .05). The total doses of propofol in esketamine 0.5 and 1 mg/kg groups were statistically lower than these in esketamine 0 and 0.25 mg/kg group (p < .01). The mean blood pressure was lower in the esketamine 0 mg/kg group than that in 1 mg/kg group after administration and during the procedure (p < .01). The esketamine 1 mg/kg group showed a higher incidence of vomiting and visual disturbances than the other three groups (p < .001).

WHAT IS NEW AND CONCLUSION

In children who accomplished diagnostic paediatric upper gastrointestinal endoscopy under deep sedation/anaesthesia, the total dosage of propofol needed was reduced significantly in esketamine 0.5 and 1 mg/kg groups with a corresponding reduce in propofol-related hemodynamic changes. However, a higher incidence of esketamine-related adverse effects was found in esketamine 1 mg/kg group.

A single nucleotide polymorphism-based formula to predict the risk of propofol TCI concentration being over 4 µg mL-1 at the time of loss of consciousness

We aim to develop a formula based on single nucleotide polymorphisms (SNPs) to predict whether the propofol target-controlled infusion (TCI) concentration would be over 4 μg mL^-1 at the time of loss of consciousness (LOC). We recruited 184 patients undergoing thyroid or breast surgeries with propofol anaesthesia. A total of 48 SNPs of CYP2B6, CYP2C9, UGT1A9, HNF4A, ABCB1, ABCC4, ABCG2, GABRA2, GABRA4, GABRB1, GABRB3, GABRG2, GABBR2, GAD1, SLC1A3, BDNF, and NRXN1, previously associated with propofol metabolic and pharmacology pathway, were genotyped. The formula was developed in the training cohort using the least absolute shrinkage and selection operator logistic regression model, and then validated in the testing cohort. The SNPs, GABBR2 rs1167768, GABBR2 rs1571927, NRXN1 rs601010, BDNF rs2049046, GABRA4 rs1512135, UGT1A9 rs11692021, GABBR2 rs2808536, HNF4A rs1884613, GABRB3 rs2017247, and CYP2B6 rs3181842 were selected to construct the SNP-based formula, which was used to calculate the risk score for over 4 μg mL^-1 TCI concentration of propofol at the time of LOC. Patients in the high-risk group were more likely to require a propofol concentration higher than 4 μg mL^-1 and presented a longer LOC latency. The SNP-based formula may significantly improve the safety and effectiveness of propofol-induced anaesthesia.

A Bibliometric Analysis of Endoscopic Sedation Research: 2001-2020

Background and Aims: To evaluate endoscopic sedation research and predict research hot spots both quantitatively and qualitatively using bibliometric analysis. Methods: We extracted relevant publications from the Web of Science Core Collection (WoSCC) on 13 December 2020. We examined the retrieved data by bibliometric analysis (e.g., co-cited and cluster analysis, keyword co-occurrence) using the software CiteSpace and VOSviewer and the website of bibliometrics, the Online Analysis Platform of Literature Metrology (http://bibliometric.com/), to analyse and predict the trends and hot spots in this field. Main Results: We identified 2,879 articles and reviews on endoscopic sedation published between 2001 and 2020. Although the overall trend is increasing, with slight fluctuation in some years, there were significant increases in 2007 and 2012. In respect of the contributions on endoscopic sedation research, the United States (US) had the greatest number of publications, and it was followed by Japan and China. In addition, collaboration network analysis revealed that the most frequent collaboration was between the US and China. Six of the top ten most prolific research institutions were located in the US. The most publications on endoscopic sedation research in the past two decades were found primarily in journals on gastroenterology and hepatology. Keyword co-occurrence and co-citation cluster analysis revealed the most popular terms relating to endoscopic sedation in the manner of cluster labels; these included patient anxiety, tolerance, ketamine, propofol, hypoxia, nursing shortage, endoscopic ultrasonography, colorectal cancer, carbon dioxide insufflation, and water exchange (WE). Keyword burst detection suggested that propofol sedation, adverse event, adenoma detection rate (ADR), hypoxemia, and obesity were newly-emergent research hot spots. Conclusions: Our findings showed that hypoxia, adverse event, and ADR, along with conscious sedation and propofol sedation, have been foci of endoscopic sedation research over the past 20 years. The research focus has shifted from sedative drugs to sedative complications and endoscopy quality control, which means that there will be higher requirements and standards for sedative quality and endoscopy quality in the future.

Estimation of effective dose of propofol mono-sedation for successful insertion of upper gastrointestinal endoscope in healthy, non-obese Chinese adults

WHAT IS KNOWN AND OBJECTIVE

Propofol is effective in sedation for upper gastrointestinal (UGI) endoscopy. However, the optimum dose is ill-defined. This study aimed to estimate the effective dose of propofol mono-sedation for successful endoscope insertion in healthy, non-obese Chinese adults undergoing single UGI endoscopy.

METHODS

Twenty-six adult patients undergoing elective single UGI endoscopy were enrolled in this study. A modified Dixon's up-and-down method was utilized to assess the effective dose of propofol for successful endoscope insertion. The initial dose of propofol administered, 1.6 mg/kg, was adjusted with 0.1 mg/kg as a step size. The patient's responses to endoscope insertion were classified as either 'movement' or 'no movement'. When patient's responses were changed from 'movement' to 'no movement' or from 'no movement' to 'movement', a crossover was defined. After eight crossovers had been obtained, patient recruitment was stopped. The mean of midpoints of all crossovers obtained by the modified Dixon's up-and-down method in all 26 patients was defined as calculated median effective dose (ED₅₀ ) of propofol for successful endoscope insertion. Furthermore, probit regression analysis was used to determine the dose of propofol where 50% (ED₅₀ ) and 95% (ED₉₅ ) of endoscope insertion attempts were successful.

RESULTS

The calculated ED₅₀ of propofol for successful endoscope insertion was 1.89 ± 0.12 mg/kg. The probit regression analysis showed that ED₅₀ and ED₉₅ of propofol for successful endoscope insertion were 1.90 mg/kg (95% CI, 1.78-2.10 mg/kg) and 2.15 mg/kg (95% CI, 2.01-3.56 mg/kg), respectively. No any patient had hypoxaemia and gag reflex during the UGI endoscopy with propofol mono-sedation.

WHAT IS NEW AND CONCLUSION

In healthy, non-obese Chinese adults, propofol mono-sedation can provide excellent conditions of UGI endoscopy and the estimated ED₅₀ of propofol for successful endoscope insertion is 1.89 ± 0.12 mg/kg.

Clinical observation of the combined use of propofol and etomidate in painless gastroscopy

OBJECTIVE

This study is aims to compare the anesthetic safety of propofol combined with etomidate for painless gastroscopy.

METHODS

Three hundred patients undergoing painless gastroscopy were randomly assigned to P, PE1, and PE2 groups. Patients were anesthetized with propofol (P group) or propofol combined with etomidate (volume ratio 1: 1, PE1 group; volume ratio 2: 1, PE2 group). The hemodynamics and adverse reactions were observed. The sleep quality satisfaction and nature of dreams were recorded.

RESULTS

Compared with pre-anesthesia, the mean arterial pressure and heart rate of the 3 groups were significantly slower during the examination and at the end of the examination. PE1 group had a higher incidence of muscle spasm, body moving, choking, and deglutition. The incidence of hypoxemia and injection pain was higher in P group. P and PE2 group had higher sleep quality satisfaction and dream incidence after awaking. However, there was no difference in the nature of dreams among 3 groups.

CONCLUSION

Our data indicate that the combination of 10 ml 1.0% propofol and 5 ml 0.2% etomidate for painless gastroscopy reduces adverse reactions while not affecting the patients respiratory function. Moreover, it is safe and effective, which is worthy of clinical application and promotion.