Safety and efficacy of a low-dose combination of midazolam, alfentanil, and propofol for deep sedation of elderly patients undergoing ERCP.

BACKGROUND: Proper sedation of patients, particularly elderly individuals, who are more susceptible to sedation-related complications, is of significant importance in endoscopic retrograde cholangiopancreatography (ERCP). This study aims to assess the safety and efficacy of a low-dose combination of midazolam, alfentanil, and propofol for deep sedation in elderly patients undergoing ERCP, compared to a group of middle-aged patients. METHODS: The medical records of 610 patients with common bile duct stones who underwent elective ERCP under deep sedation with a three-drug regimen, including midazolam, alfentanil, and propofol at Shandong Provincial Third Hospital from January 2023 to September 2023 were retrospectively reviewed in this study. Patients were categorized into three groups: middle-aged (50-64 years, n = 202), elderly (65-79 years, n = 216), and very elderly (≥ 80 years, n = 192). Intraoperative vital signs and complications were compared among these groups. RESULTS: The three groups showed no significant difference in terms of intraoperative variation of systolic blood pressure (P = 0.291), diastolic blood pressure (P = 0.737), heart rate (P = 0.107), peripheral oxygen saturation (P = 0.188), bispectral index (P = 0.158), and the occurrence of sedation-related adverse events including hypotension (P = 0.170) and hypoxemia (P = 0.423). CONCLUSION: The results suggest that a low-dose three-drug regimen consisting of midazolam, alfentanil, and propofol seems safe and effective for deep sedation of elderly and very elderly patients undergoing ERCP procedures. However, further studies are required to verify these findings and clarify the benefits and risks of this method.

Continuous palliative sedation until death: a qualitative study of palliative care clinicians' experiences.

BACKGROUND: The practice of continuous palliative sedation until death is the subject of much medical and ethical debate, which is reflected in the inconsistency that persists in the literature regarding the definition and indications of palliative sedation. AIM: This study aims to gain a better understanding of palliative care clinicians' experiences with continuous palliative sedation. DESIGN: We conducted a qualitative study based on focus group discussions. SETTING/PARTICIPANTS: We conducted six focus groups with a total of 28 palliative care clinicians (i.e., 15 nurses, 12 physicians, and 1 end-of-life doula) from diverse care settings across Canada, where assisted dying has recently been legalized. RESULTS: An interpretative phenomenological analysis was used to consolidate the data into six key themes: responding to suffering; grappling with uncertainty; adapting care to ensure ongoing quality; grounding clinical practice in ethics; combining medical expertise, relational tact, and reflexivity; and offering an alternative to assisted death. CONCLUSIONS: Interaction with the patient's family, uncertainty about the patient's prognosis, the concurrent practice of assisted dying, and the treatment of existential suffering influence the quality of sedation and indicate a lack of clear palliative care guidelines. Nevertheless, clinicians exhibit a reflective and adaptive capacity that can facilitate good practice.

Apnea during moderate to deep sedation using continuous infusion of remimazolam compared to propofol and dexmedetomidine: A retrospective observational study.

Remimazolam's rapid onset and offset make it an innovative sedative for use during regional anesthesia. However, its respiratory safety profile is not well understood. We compared the continuous infusion of remimazolam with commonly used sedatives, propofol and dexmedetomidine, after regional anesthesia. In this retrospective study, the incidence of apnea (>10 seconds) was assessed in patients who underwent orthopedic surgery under regional anesthesia and received moderate to deep sedation using continuous infusion of remimazolam (group R: 0.1 mg/kg in 2 minutes followed by 0.5 mg/kg/hr). The incidence was compared with that of propofol (group P: 2-3 µg/mL target-controlled infusion) and dexmedetomidine (group D: 1 µg/kg in 10 minutes followed by 0.4-1 µg/kg/hr). Propensity score weighted multivariable logistic regression model was utilized to determine the effects of the sedative agents on the incidence of apnea. A total of 634 (191, 278, and 165 in group R, P, and D) cases were included in the final analysis. The incidence of apnea was 63.9%, 67.3%, and 48.5% in group R, P, and D, respectively. The adjusted odds ratios for apnea were 2.33 (95% CI, 1.50 to 3.61) and 2.50 (95% CI, 1.63 to 3.85) in group R and P, compared to group D. The incidence of apnea in patients receiving moderate to deep sedation using continuous infusion of remimazolam with dosage suggested in the current study was over 60%. Therefore, careful titration and respiratory monitoring is warranted.

Palliative sedation - revised recommendations.

Palliative sedation is defined as the monitored use of medications intended to induce a state of decreased or absent awareness (unconsciousness) to relieve the burden of otherwise intractable suffering in a manner ethically acceptable to the patient, their family, and healthcare providers. In Switzerland, the prevalence of continuous deep sedation until death increased from 4.7% in 2001 to 17.5% of all deceased in 2013, depending on the research method used and on regional variations. Yet, these numbers may be overestimated due to a lack of understanding of the term "continuous deep sedation" by for example respondents of the questionnaire-based study. Inadequately trained and inexperienced healthcare professionals may incorrectly or inappropriately perform palliative sedation due to uncertainties regarding its definitions and practice. Therefore, the expert members of the Bigorio group and the authors of this manuscript believe that national recommendations should be published and made available to healthcare professionals to provide practical, terminological, and ethical guidance. The Bigorio group is the working group of the Swiss Palliative Care Society whose task is to publish clinical recommendations at a national level in Switzerland. These recommendations aim to provide guidance on the most critical questions and issues related to palliative sedation. The Swiss Society of Palliative Care (palliative.ch) mandated a writing board comprising four clinical experts (three physicians and one ethicist) and two national academic experts to revise the 2005 Bigorio guidelines. A first draft was created based on a narrative literature review, which was internally reviewed by five academic institutions (Lausanne, Geneva, Bern, Zürich, and Basel) and the heads of all working groups of the Swiss Society of Palliative Care before finalising the guidelines. The following themes are discussed regarding palliative sedation: (a) definitions and clinical aspects, (b) the decision-making process, (c) communication with patients and families, (d) patient monitoring, (e) pharmacological approaches, and (f) ethical and controversial issues. Palliative sedation must be practised with clinical and ethical accuracy and competence to avoid harm and ethically questionable use. Specialist palliative care teams should be consulted before initiating palliative sedation to avoid overlooking other potential treatment options for the patient's symptoms and suffering.

Bolus administration of remimazolam was superior to midazolam for deep sedation in elderly patients undergoing diagnostic bronchoscopy: A randomized, double-blind, controlled trial.

BACKGROUND: To date, there is no standardized practice for the use of pharmacological sedatives during flexible bronchoscopy, particularly for elderly patients. This exploratory study aimed to assess the efficacy and safety of remimazolam at a single induced dose for deep sedation in elderly patients undergoing diagnostic flexible bronchoscopy (DFB), and compare with midazolam, a commonly used sedative. METHODS: A total of 100 elderly patients (age range 65-80 yr; American Society of Anesthesiologists Physical Status I-III) undergoing DFB were randomly allocated into 2 groups according to the sedatives used for induction: the remimazolam group and the midazolam group. Sedation induction was initiated by an intravenous bolus of remimazolam (0.135 mg/kg) or midazolam (0.045 mg/kg), respectively, both groups were combined with a high-dose of alfentanil (18 µg/kg), and supplemented with high-flow nasal cannula (HFNC) oxygen supply at a flow rate of 45 L/min. If the target depth of sedation was not achieved, propofol would be titrated as a rescue. The primary outcome was the success rate of sedation at a single induced dose to achieve target depth (Ramsay sedation score [RSS] = 4) during induction, intraoperative changes in vital signs, postoperative follow-up situation and incidence of post-bronchoscopy adverse events were evaluated as secondary outcomes. RESULTS: The success rate of sedation in the remimazolam group was significantly higher than that in the midazolam group (65.2% vs 39.6%, P = .013), while the incidence of extra sleep within 6 hours after procedure was lower in the remimazolam group as compared to the midazolam group (10.9% vs 31.3%, P = .016). No statistically significant differences were observed between the 2 groups regarding hemodynamic fluctuations, incidence of hypoxemia, and cough response during the procedure, as well as postoperative recall, willingness to undergo reexamination, and other post-bronchoscopy adverse events. CONCLUSIONS: Bolus administration of remimazolam offers advantages over midazolam for deep sedation in elderly patients undergoing DFB, in terms of a higher success rate of sedation and a lower incidence of extra sleep within 6 hours after procedure, though the safety profiles of both groups were favorable.

Expanding the Use of Continuous Sedation Until Death and Physician-Assisted Suicide.

The controversy over the equivalence of continuous sedation until death (CSD) and physician-assisted suicide/euthanasia (PAS/E) provides an opportunity to focus on a significant extended use of CSD. This extension, suggested by the equivalence of PAS/E and CSD, is designed to promote additional patient autonomy at the end-of-life. Samuel LiPuma, in his article, "Continuous Sedation Until Death as Physician-Assisted Suicide/Euthanasia: A Conceptual Analysis" claims equivalence between CSD and death; his paper is seminal in the equivalency debate. Critics contend that sedation follows proportionality protocols for which LiPuma's thesis does not adequately account. Furthermore, sedation may not eliminate consciousness, and as such LiPuma's contention that CSD is equivalent to neocortical death is suspect. We not only defend the equivalence thesis, but also expand it to include additional moral considerations. First, we explain the equivalence thesis. This is followed by a defense of the thesis against five criticisms. The third section critiques the current use of CSD. Finally, we offer two proposals that, if adopted, would broaden the use of PAS/E and CSD and thereby expand options at the end-of-life.

Revised European Association for Palliative Care (EAPC) recommended framework on palliative sedation: An international Delphi study.

BACKGROUND: The European Association for Palliative Care (EAPC) acknowledges palliative sedation as an important, broadly accepted intervention for patients with life-limiting disease experiencing refractory symptoms. The EAPC therefore developed 2009 a framework on palliative sedation. A revision was needed due to new evidence from literature, ongoing debate and criticism of methodology, terminology and applicability. AIM: To provide evidence- and consensus-based guidance on palliative sedation for healthcare professionals involved in end-of-life care, for medical associations and health policy decision-makers. DESIGN: Revision between June 2020 and September 2022 of the 2009 framework using a literature update and a Delphi procedure. SETTING: European. PARTICIPANTS: International experts on palliative sedation (identified through literature search and nomination by national palliative care associations) and a European patient organisation. RESULTS: A framework with 42 statements for which high or very high level of consensus was reached. Terminology is defined more precisely with the terms suffering used to encompass distressing physical and psychological symptoms as well as existential suffering and refractory to describe the untreatable (healthcare professionals) and intolerable (patient) nature of the suffering. The principle of proportionality is introduced in the definition of palliative sedation. No specific period of remaining life expectancy is defined, based on the principles of refractoriness of suffering, proportionality and independent decision-making for hydration. Patient autonomy is emphasised. A stepwise pharmacological approach and a guidance on hydration decision-making are provided. CONCLUSIONS: This is the first framework on palliative sedation using a strict consensus methodology. It should serve as comprehensive and soundly developed information for healthcare professionals.

The effects of selected sedatives on basal and stimulated serum cortisol concentrations in healthy dogs.

Background: Hormone assessment is typically recommended for awake, unsedated dogs. However, one of the most commonly asked questions from veterinary practitioners to the endocrinology laboratory is how sedation impacts cortisol concentrations and the adrenocorticotropic hormone (ACTH) stimulation test. Butorphanol, dexmedetomidine, and trazodone are common sedatives for dogs, but their impact on the hypothalamic-pituitary-adrenal axis (HPA) is unknown. The objective of this study was to evaluate the effects of butorphanol, dexmedetomidine, and trazodone on serum cortisol concentrations. Methods: Twelve healthy beagles were included in a prospective, randomized, four-period crossover design study with a 7-day washout. ACTH stimulation test results were determined after saline (0.5 mL IV), butorphanol (0.3 mg/kg IV), dexmedetomidine (4 µg/kg IV), and trazodone (3-5 mg/kg PO) administration. Results: Compared to saline, butorphanol increased basal (median 11.75 µg/dL (range 2.50-23.00) (324.13 nmol/L; range 68.97-634.48) vs 1.27 µg/dL (0.74-2.10) (35.03 nmol/L; 20.41-57.93); P < 0.0001) and post-ACTH cortisol concentrations (17.05 µg/dL (12.40-26.00) (470.34 nmol/L; 342.07-717.24) vs 13.75 µg/dL (10.00-18.90) (379.31 nmol/L; 275.96-521.38); P ≤ 0.0001). Dexmedetomidine and trazodone did not significantly affect basal (1.55 µg/dL (range 0.75-1.55) (42.76 nmol/L; 20.69-42.76); P = 0.33 and 0.79 µg/dL (range 0.69-1.89) (21.79 nmol/L; 19.03-52.14); P = 0.13, respectively, vs saline 1.27 (0.74-2.10) (35.03 nmol/L; 20.41-57.93)) or post-ACTH cortisol concentrations (14.35 µg/dL (range 10.70-18.00) (395.86 nmol/L; 295.17-496.55); (P = 0.98 and 12.90 µg/dL (range 8.94-17.40) (355.86 nmol/L; 246.62-480); P = 0.65), respectively, vs saline 13.75 µg/dL (10.00-18.60) (379.31 nmol/L; 275.86-513.10). Conclusion: Butorphanol administration should be avoided prior to ACTH stimulation testing in dogs. Further evaluation of dexmedetomidine and trazodone's effects on adrenocortical hormone testing in dogs suspected of HPA derangements is warranted to confirm they do not impact clinical diagnosis.

Ethnic Disparities in Deep Sedation of Patients with Acute Respiratory Distress Syndrome in the United States: Secondary Analysis of a Multicenter Randomized Trial.

Rationale: Patients identified as Hispanic, the largest minority group in the United States, are more likely to die from acute respiratory distress syndrome (ARDS) than non-Hispanic patients. Mechanisms to explain this disparity remain unidentified. However, Hispanic patients may be at risk of overexposure to deep sedation because of language differences between patients and clinicians, and deep sedation is associated with higher ARDS mortality.Objective: We examined associations between Hispanic ethnicity and exposure to deep sedation among patients with ARDS.Methods: A secondary analysis was conducted of patients enrolled in the control arm of a randomized trial of neuromuscular blockade for ARDS across 48 U.S. hospitals. Exposure to deep sedation was measured over the first 5 days that a patient was alive and received mechanical ventilation. Multilevel mixed-effects models were used to evaluate associations between Hispanic ethnicity and exposure to deep sedation, controlling for patient characteristics.Results: Patients identified as Hispanic had approximately five times the odds of deep sedation (odds ratio, 4.98; 95% confidence interval, 2.02-12.28; P < 0.0001) on a given day, compared with non-Hispanic White patients. Hospitals with at least one enrolled Hispanic patient kept all enrolled patients deeply sedated longer than hospitals without any enrolled Hispanic patients (85.8% of ventilator-days vs. 65.5%; P < 0.001).Conclusions: Hispanic patients are at higher risk of exposure to deep sedation than non-Hispanic White patients. There is an urgent need to understand and address disparities in sedation delivery.

Terminological Confusion About Sedation in Palliative Care: Results of an International Online Vignette Survey.

Background: Terminological problems concerning sedation in palliative care and consequences for research and clinical decision making have been reported frequently. Objectives: To gather data on the application of definitions of sedation practices in palliative care to clinical cases and to analyze implications for high-quality definitions. Design: We conducted an online survey with a convenience sample of international experts involved in the development of guidelines on sedation in palliative care and members of the European Association for Palliative Care (EAPC). Participants were asked to apply four published definitions to four case vignettes. Data were analyzed using descriptive statistics. Results: A total of 32 experts and 271 EAPC members completed the survey. The definitions were applied correctly in n = 2200/4848 cases (45.4%). The mean number of correct applications of the definitions (4 points max.) was 2.2 ± 1.14 for the definition of the SedPall study group, 1.8 ± 1.03 for the EAPC definition, 1.7 ± 0.98 for the definition of the Norwegian Medical Association, and 1.6 ± 1.01 for the definition of the Japanese Society of Palliative Medicine. The rate of correct applications for the 16 vignette-definition pairs varied between 70/303 (23.1%) and 227/303 (74.9%). The content of definitions and vignettes together with free-text comments explains participants' decisions and misunderstandings. Conclusions: Definitions of sedation in palliative care are frequently incorrectly applied to clinical case scenarios under simplified conditions. This suggests that clinical communication and research might be negatively influenced by misunderstandings and inconsistent labeling or reporting of data. Clinical Trial Registration Number: DRKS00015047.

Continuous Deep Sedation Until Death of Children at the End of Life: French Physicians' Opinions.

Objectives: To evaluate physicians' opinions concerning continuous deep sedation until death (CDSUD) and implementation of Claeys-Leonetti; a law intended to be applicable to all patients, but without a specific framework for children thus giving rise to ethically and legally complex situations. The secondary objective was to identify if physicians' characteristics could influence their opinions. Study Design: This was a national, multicenter, noninterventional cross-sectional survey from January 30, 2020, until March 1, 2020. The target population consisted of French physicians involved in children's end-of-life situations. The validated questionnaire explored respondents' characteristics and their opinions on four hypothetical pediatric clinical cases. Results: Analysis was conducted on 391 respondents. The oncological situation was more easily recognized as end of life compared with the neurological pathology (77% vs. 40.4%). Dependence on mechanical ventilation was another major factor influencing physicians in identifying end-of-life situations. Physicians clearly recognized the difference in intention between CDSUD and euthanasia. They accepted to implement CDSUD more easily in newborns. The withdrawal of artificial nutrition and hydration gave rise to divergent opinions. Respondents were in favor of adolescents' decision-making autonomy and their access to drafting advance directives. The child's best interest prevailed in case of objection by parents, except in situations outside the law's framework or in cases of disagreement within the health care team. Conclusion: Results of our study showed differences in the interpretation of the law concerning the CDSUD application framework and provide elements for reflection, which may ultimately contribute to the development of specific guidelines in CDSUD in children at the end of life.

Rocuronium Dosing by Ideal vs Total Body Weight in Obesity: A Prospective, Observational Non-inferiority Study.

Background: Providing adequate paralysis and appropriate sedation is challenging in patients with obesity during rapid sequence intubation (RSI). Pharmacokinetic parameters play an important role in dosing of rocuronium due to low lipophilicity. Rocuronium may be dosed based on ideal body weight (IBW). Current guidelines do not offer recommendations for dosing in the setting of obesity. Dosing depends on clinician preference based on total body weight (TBW) or IBW. Objective: In this study we performed non-inferiority analysis to compare the intubation conditions, duration of paralysis, and incidence of new-onset tachycardia or hypertension after intubation in obese patients requiring RSI in the emergency department (ED). Methods: This was a single-center, prospective, observational study. Eligible for enrollment were adult patients with a TBW ≥30% IBW or body mass index ≥30 kilograms per meters squared who presented to the ED requiring RSI with the use of rocuronium. Rocuronium was dosed according to intubating physicians' preference. Physicians completed a survey assessing intubation conditions. Height and weight used for the calculation of the dose, the dose of rocuronium, time of administration, and time of muscle function recovery were recorded. Endpoints assessed included grading of view during laryngoscopy, first-past success, and duration of paralysis. Results: In total, 96 patients were included, 54 in TBW and 42 in IBW. The TBW cohort received a mean of 1 milligram per kilogram (mg/kg) compared to 0.71 mg/kg in the IBW group. Excellent intubation conditions were observed in 68.5% in the TBW group and 73.8% in the IBW group. The non-inferiority analysis for relative risk of excellent intubation was 1.12 (P = 0.12, [90% CI 0.80-1.50]). Conclusion: Non-inferiority analysis suggests that IBW dosing provides similar optimal intubation conditions when compared to TBW dosing, but the noninferiority comparison did not reach statistical significance. This study was unable to show statistical non-inferiority for IBW dosing.

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.

Supraglottic Jet Oxygenation and Ventilation to Minimize Hypoxia in Patients Receiving Flexible Bronchoscopy Under Deep Sedation: A 3-Arm Randomized Controlled Trial.

BACKGROUND: Hypoxia often occurs due to shared airway and anesthetic sedation-induced hypoventilation in patients receiving flexible bronchoscopy (FB) under deep sedation. Previous evidence has shown that supraglottic jet oxygenation and ventilation (SJOV) via Wei nasal jet tube (WNJ) reduces the incidence of hypoxia during FB. This study aimed to investigate the extent to which SJOV via WNJ could decrease the incidence of hypoxia in patients under deep sedation as compared to oxygen supplementation via WNJ alone or nasal catheter (NC) for oxygen supplementation during FB. METHODS: This was a single-center 3-arm randomized controlled trial (RCT). Adult patients scheduled to undergo FB were randomly assigned to 3 groups: NC (oxygen supplementation via NC), low-pressure low-flow (LPLF) (low-pressure oxygen supplementation via WNJ alone), or SJOV (high-pressure oxygen supplementation via WNJ). The primary outcome was hypoxia (defined as peripheral saturation of oxygen [Sp o2 ] <90% lasting more than 5 seconds) during FB. Secondary outcomes included subclinical respiratory depression or severe hypoxia, and rescue interventions specifically performed for hypoxia treatment. Other evaluated outcomes were sore throat, xerostomia, nasal bleeding, and SJOV-related barotraumatic events. RESULTS: One hundred and thirty-two randomized patients were included in 3 interventions (n = 44 in each), and all were included in the final analysis under intention to treat. Hypoxia occurred in 4 of 44 patients (9.1%) allocated to SJOV, compared to 38 of 44 patients (86%) allocated to NC, with a relative risk (RR) for hypoxia, 0.11; 98% confidence interval (CI), 0.02-0.51; P < .001; or to 27 of 44 patients (61%) allocated to LPLF, with RR for hypoxia, 0.15; 95% CI, 0.04-0.61; P < .001, respectively. The percentage of subclinical respiratory depression was also significantly diminished in patients with SJOV (39%) compared with patients with NC (100%) or patients with LPLF (96%), both P < .001. In SJOV, no severe hypoxia event occurred. More remedial interventions for hypoxia were needed in the patients with NC. Higher risk of xerostomia was observed in patients with SJOV. No severe adverse event was observed throughout the study. CONCLUSIONS: SJOV via WNJ effectively reduces the incidence of hypoxia during FB under deep sedation.

Preliminary evaluation of the efficacy and safety of brimonidine for deep sedation.

BACKGROUND: Although brimonidine is currently used in the clinical treatment of glaucoma and rosacea, research of the deep sedative effect on animals after systemic administration is reported firstly and has shown promising results. METHODS: The median effective dose (ED50 ), the median lethal dose (LD50 ), and the therapeutic index of brimonidine for deep sedation and formalin stimulation assay were determined by various animal experiments. The effect of synergistic anesthesia in rabbits with brimonidine and chloral hydrate was preliminarily evaluated. RESULTS: The ED50 of brimonidine for highly effective sedation by intraperitoneal injection in rats was calculated to be 2.05 mg kg-1 with a 95% confidence interval (CI) of 1.87 to 2.25 mg kg-1 . The ED50 of brimonidine for deep sedation by intravenous and intrarectal injection in rabbits was calculated to be 0.087 mg kg-1 with a 95% CI of 0.084 to 0.091 mg kg-1 and 1.65 mg kg-1 with a 95% CI of 1.43 to 1.91 mg kg-1 , respectively. The LD50 of intraperitoneal brimonidine injection in rats was calculated to be 468 mg kg-1 with a 95% CI of 441 to 497 mg kg-1 and a therapeutic index of 228. Brimonidine has a certain analgesic and heart rate lowering effects. CONCLUSION: The results confirmed that brimonidine has deep sedation and analgesic effects after systemic administration and has high safety. It can be used in combination with other types of sedative drugs to achieve better effects.

Deep continuous sedation at the patient's request until death in a palliative care unit: retrospective study.

OBJECTIVES: Limited descriptive data are available on continuous and deep sedation maintained until death (CDSUD) at the patient's request in palliative care units. This study aimed to describe such practices in the context of refractory suffering or after a request to stop life-sustaining treatment, evaluating the duration and dosage of sedative treatments used. METHODS: This retrospective observational study included consecutively hospitalised patients in a palliative care unit from January 2020 to December 2021. Data on patient profiles, reasons for the sedation request, duration of sedation and doses of sedatives were collected. RESULTS: Among 42 patients who underwent CDSUD, 79% occurred due to refractory suffering. In cases of sedation following a request to stop life support, high-dose corticosteroid therapy was the most commonly involved life-sustaining treatment. Midazolam was always the first-line sedative treatment. Chlorpromazine was added in 79% of cases, and propofol in 40%, to achieve a deep level of sedation. The mean maximum doses of midazolam, chlorpromazine and propofol were 7.6 mg/hour (±1.9), 3.3 mg/hour (±0.9) and 1.7 mg/kg/hour, respectively. The average duration of sedation was 37 hours. CONCLUSIONS: This study provides new descriptive elements on CDSUD. Notably, it highlights the use of second-line sedative molecules, such as propofol.