Effect of clonidine premedication on haemodynamic responses to fibreoptic bronchoscopy

ED50 of ciprofol combined with sufentanil for fiberoptic bronchoscopy of different patient populations with pulmonary tuberculosis

BACKGROUND

Ciprofol is a promising sedative. This study aims to explore the median effective dose (ED50) of ciprofol in inhibiting responses to fiberoptic bronchoscopy in patients with pulmonary tuberculosis (PTB) of different genders and ages when combined with 0.15 μg/kg sufentanil, and to evaluate its efficacy and safety, providing a reference for the rational use of ciprofol in clinical practice.

METHODS

PTB patients who underwent bronchoscopy examination and treatment at The Third People's Hospital of Changzhou between May 2023 and June 2023 were selected and divided into four groups using a stratified random method. All patients received intravenous injection of 0.15 μg/kg sufentanil followed by injection of the test dose of ciprofol according to Dixon's up-and-down method. The initial dose of ciprofol in all four groups was 0.4 mg/kg, with an adjacent ratio of 1:1.1. The next patient received a 10% increase in the dose of ciprofol if the previous patient in the same group experienced positive reactions such as choking cough, frowning, and body movements during the endoscopy. Otherwise, it was judged as a negative reaction, and the next patient received a 10% decrease in the dose of ciprofol. The transition from a positive reaction to a negative reaction was defined as a turning point, and the study of the group was terminated when seven turning points occurred. Hemodynamic parameters, oxygen saturation and adverse reactions were recorded at different time points in all groups. The Probit regression analysis method was used to calculate the ED50 of ciprofol in the four groups and compare between the groups.

RESULTS

The ED50 of ciprofol combined with 0.15 μg/kg sufentanil for bronchoscopy in the four groups were 0.465 mg/kg, 0.433 mg/kg, 0.420 mg/kg and 0.396 mg/kg, respectively.

CONCLUSION

The ED50 of ciprofol used for fiberoptic bronchoscopy varied among PTB patients of different genders and ages.

TRIAL REGISTRATION

The Chinese Clinical Trial Registry, ChiCTR2300071508, Registered on 17 May 2023.

Efficacy of intravenous midazolam versus clonidine as premedicants on bispectral index guided propofol induction of anesthesia in laparoscopic cholecystectomy: A randomized control trial

BACKGROUND

Midazolam and clonidine are preferred premedicants whose effects are not restricted to the preoperative period. In addition, these premedicants significantly modulate not only the intraoperative requirements of the anesthetic agents, but also the postoperative outcome. We aim to compare the efficacy of both the agents in view of premedication, induction characteristics, hemodynamic changes and postoperative complications utilizing bispectral index (BIS) using propofol anesthesia.

MATERIALS AND METHODS

The type of this study was randomized control trial conducted on patients undergoing laparoscopic cholecystectomy under general anesthesia with endotracheal intubation. Study included 105 patients of either sex aged 20-60 years. The patients were randomly allocated into three groups: Intravenous midazolam (Group 1), clonidine (Group 2), and normal saline (Group 3) (control). The initial value of BIS and Ramsay Sedation Score, dose of propofol required for induction were noted in each group and monitored for pulse rate, electrocardiograph, noninvasive blood pressure, and BIS.

RESULTS

The requirement of propofol ranged from 40 to 150 mg. Mean requirement was maximum in Group 3 (109.43 ± 20.14 mg) and it was minimum in Group 1 (78.57 ± 22.15 mg). A significant reduction in consumption of propofol with the use of midazolam (P < 0.001) and clonidine (P < 0.001) was observed. Both premedicants partially attenuates laryngoscoy and intubation response along with reduction in the incidence of postoperative complications.

CONCLUSION

Both clonidine and midazolam contributed equally in lowering propofol consumption. Reduction in the induction dosage of propofol and hemodynamic variations were also observed to be similar with the use of midazolam or clonidine as premedicants. Both provide a beneficial effect in relation to recovery and less postoperative complications. However clonidine premedication was found to be more effective in preventing post operative shivering and can be recommended in routine practice.

Dexmedetomidine versus Midazolam for Conscious Sedation in Postoperative Patients Undergoing Flexible Bronchoscopy: A Randomized Study

OBJECTIVE: This prospective randomized study evaluated the efficacy and patient tolerance of dexmedetomidine compared with midazolam for sedation in postoperative patients undergoing flexible bronchoscopy. METHODS: A total of 198 postoperative patients were randomized to receive dexmedetomidine ( n = 99) or midazolam ( n = 99) to produce conscious sedation for bronchoscopy. Peripheral oxygen saturation, heart rate and systolic and diastolic arterial pressures were recorded before, during and after the procedure. Patient tolerance was recorded using various visual analogue scales. RESULTS: The mean lowest peripheral oxygen saturation was significantly lower in the midazolam group than in the dexmedetomidine group. Heart rate and systolic arterial pressure were both significantly higher during bronchoscopy in the midazolam group than in the dexmedetomidine group. Bronchoscopy was well tolerated in both groups; there was no between-group difference in patient discomfort scores or in the percentage of patients who would accept repeat bronchoscopy. CONCLUSIONS: Compared with midazolam, dexmedetomidine provided better oxygen saturation and was equally well tolerated for conscious sedation in postoperative patients undergoing bronchoscopy.

[Flexible bronchoscopy as it is lived by the patient]

INTRODUCTION

Flexible bronchoscopy is an indispensable complementary exam in respiratory medicine for both diagnosis of many pulmonary diseases and their treatment. Only a few studies in literature have been conducted to evaluate the safety and acceptability of this act.

PATIENTS AND METHODS

Prospective, mono-center, non-comparative study involving 120 patients who underwent a flexible bronchoscopy for diagnostic.

RESULTS

During the study, flexible bronchoscopy has caused neither deaths nor major complications. However, minor incidents have been deplored: hemoptysis (13.3%), epistaxis (3.3%), desaturation less than 90% (4.2%), laryngospasm (3.3%) and vagal discomfort (1.7%). 56.7% of patients were anxious before the exam and 24% of patients preferred to have general anesthesia. The patients reported cough in 78.3% of cases, difficulty in breathing in 55% of cases and pain in 13.3% of cases. The occurrence of nausea, noted in 15.8% of cases, was correlated with the pathway of the bronchoscope (P=0.002). At the end of the endoscopy, 67.5% of patients agreed to repeat the examination, if necessary, under the same conditions.

CONCLUSION

The results of our study confirm that many complications during a flexible bronchoscopy are rare and generally mild failing in life-threatening. However, the occurrence of discomfort (cough, pain, vomiting, dyspnea) or incidents (asphyxia, vagal discomfort, laryngeal spasm) are likely to alter patient comfort during the exam.

Clonidine as a pre-anesthetic agent for flexible bronchoscopy

Several drugs have been employed for sedation during flexible fiberoptic bronchoscopy (FOB). Clonidine attenuates stress-induced sympathoadrenal responses and has sedative properties. We investigate the effects of clonidine premedication on hemodynamic and comfort parameters of patients submitted to FOB under airway topical anesthesia only. Patients received placebo (n = 22; men = 16; median age = 50.5 years) or intravenous clonidine (3 microg/kg; n = 20; men = 15; median age = 46.0 years) 15 min before FOB. Blood pressure (BP), heart rate (HR), plasma norepinephrine (nor) and cortisol levels were measured before, during, and 1 h after FOB. Comfort was assessed by the examiner and by the patients using a visual numerical scale (0-10). The placebo group showed significant increases in systolic BP, HR, and nor levels during FOB (SBP = 125 mmHg x 145 mmHg; HR = 74 bpm x 85 bpm; nor = 316.2 pg/dl x 483.1 pg/dl), whereas clonidine group did not display such changes. Clonidine group showed a lower frequency of cardiac arrhythmias than the placebo group during and after FOB (supraventricular = 39% x 50%; ventricular = 22% x 40%). Levels of comfort were high and comparable in both groups. We concluded that although clonidine led to a somewhat better hemodynamic profile, it did not contribute to better comfort in this setting.

Dexmedetomidine infusion for sedation during fiberoptic intubation: a report of three cases

We report three patients undergoing cervical spine surgery who required awake fiberoptic intubation, and in whom sedation was provided using a dexmedetomidine infusion. Dexmedetomidine was used to provide a moderate level of sedation without causing respiratory distress or hemodynamic instability during fiberoptic intubation. Conditions for intubation were acceptable in all three patients after co-administration of topical anesthesia. Dexmedetomidine may serve as a useful adjunct for this procedure. The anesthetic management and anesthetic implications of using dexmedetomidine infusions for awake fiberoptic intubation are discussed.

Difficult airway management in a patient with severe aortic stenosis, coronary artery disease, and heart failure

We report a patient with aortic stenosis, coronary artery disease, and heart failure in whom awake fiberoptic intubation was performed because the patient's mouth opening was insufficient as a result of disc prolapse of the mandibular joint. We planned to perform this procedure during conscious sedation, spontaneous respiration, and with stable hemodynamic parameters (no tachycardia, hypertension, or hypotension). After oral premedication with dikaliumclorazepate, the patient received clonidine. Fiberoptic intubation was performed while the patient breathed spontaneously. Throughout the procedure, no adverse events occurred. Clonidine is a valuable adjunct for conscious sedation and can be used safely for sympathicolysis, even in patients with aortic stenosis.

Sedation in outpatient bronchoscopy

Bronchoscopy is a procedure that is likely to provoke anxiety as the patient is surrounded by monitoring and bronchoscopy equipment, and care is administered by strangers who perform intimate, invasive, and sometimes, painful procedures. Sedation is needed, therefore, to allay anxiety and reduce stress, improve patient comfort and co-operation, provide amnesia and facilitate the bronchoscopic procedure. In this review we try to summarize the current knowledge on currently used sedation protocols with special reference to the commonly used pharmacological agents. We believe sedation should be used routinely in fiberoptic bronchoscopy in order to achieve a safe and pleasant procedure for both the patient and the pulmonologist.