The haemodynamic effects of bronchoscopy. Comparison of propofol and thiopentone with and without alfentanil pretreatment

Improving patient safety after rigid bronchoscopy in adults: laryngeal mask airway versus face mask - a pilot study

Background

There are still no clear guidelines in the literature on per procedural bronchoscopic management for anesthesiologists, and few relevant datasets are available. To obtain rapid recovery from anesthesia, it is often necessary to keep patients in the recovery room for several hours until they become clinically stable. In this study, we tested the hypothesis that the laryngeal mask airway (LMA) enables better respiratory and hemodynamic recovery than the oxygen face mask (FM) in patients undergoing rigid bronchoscopy.

Methods

Twenty-one patients undergoing elective bronchoscopy of the upper airway were randomized to ventilation assistance with FM or LMA after a rigid bronchoscopy procedure under general anesthesia. The primary endpoint was duration of post-surgical recovery and the secondary endpoints were postoperative hemodynamic and respiratory parameters. Assessment of the study endpoints was performed by an intensive care specialist blinded to the method of ventilation used. The statistical analysis was performed using the Fisher’s Exact test for nominal data and the Student’s t-test for continuous data.

Results

There was no statistically significant difference in post-procedural time between the two groups (P=0.972). The recovery parameters were significantly better in the LMA group than in the FM group, with significantly fewer desaturation, hypotensive, and bradycardic events (P<0.05).

Conclusion

We conclude that the LMA may be safer and more comfortable than the FM in patients undergoing rigid bronchoscopy.

Comparison of propofol and the combination of propofol and alfentanil during bronchoscopy: a randomized study

BACKGROUND

propofol is an excellent sedative agent for use in patients undergoing bronchoscopy. The addition of an opioid to propofol can be advantageous because of the antitussive effect of the opioid and the possible improvement in sedation quality. However, it may increase the risk of hypoxaemia. To investigate the effect of the addition of alfentanil to propofol, we performed a prospective study to compare propofol-only sedation with propofol-alfentanil combination sedation in patients undergoing bronchoscopy.

METHODS

patients were randomly assigned either to the propofol-only (group P, n=32) or to the propofol-alfentanil combination group (group PA, n=32). The average peripheral oxygen saturation (SpO(2) ) and the lowest SpO(2) during the sedation were compared. Patient and bronchoscopist satisfaction as well as the degree of coughing were compared using a 100 mm visual analogue scale, where 0 indicated the least and 100 indicated the most satisfied.

RESULTS

group P had the higher average SpO(2) (%) during the procedure than group PA (97.8 ± 1.6 and 96.4 ± 1.1, P<0.01) as well as the lowest SpO(2) (%) (95.4 ± 2.7 and 94.0 ± 2.4, P<0.05). Patient satisfaction (92.2 ± 13.5 and 92.3 ± 18.2), bronchoscopist satisfaction (76.6 ± 18.1 and 72.8 ± 19.1), and degree of cough (73.4 ± 22.7 and 72.2 ± 18.5; group P and group PA, respectively) were not different between the groups.

CONCLUSIONS

the combination of propofol and alfentanil resulted in a greater respiratory depression than propofol alone; furthermore, the addition of an opioid did not improve the quality of sedation. In conclusion, we do not recommend sedation with propofol and alfentanil during bronchoscopy.

Bispectral index values during elective rigid bronchoscopy: a prospective observational pilot study

Rigid bronchoscopy is associated with a high incidence of haemodynamic disturbance and awareness under anaesthesia. Anaesthetic agents are given both to attenuate the sympathetic response to bronchoscopy and to prevent awareness. Use of the Bispectral index to guide anaesthesia has shown to reduce awareness and improve recovery times from general anaesthesia. We undertook a prospective observational study of BIS values in 50 patients during routine anaesthesia for rigid bronchoscopy. BIS values were found to be between 40-60 during bronchoscopy for only 0.5% of the time (0-11.5%[0-98.7%]), median (interquartile range [range]). Patients had a BIS < 40 for 99.6% (87.9-100%[0-100%]) of the duration of bronchoscopy. We identified one case of possible awareness. Few of our patients undergoing general anaesthesia for rigid bronchoscopy had BIS scores in the suggested range of between 40 and 60. BIS < 40 was more frequent than in previous studies of different surgical populations. There was no difference in the BIS values of patients anaesthetised with intermittent boluses or target controlled infusions of propofol.

Anesthesia for airway surgery

Surgery of the upper airway requires diagnostic or therapeutic manipulation of the respiratory tree despite ongoing ventilation. Whether internal or external access to the conducting airway is required, anesthesiologist and surgeon, who must work together closely, share the airway. The anesthetic technique is influenced by the chosen mode of ventilation.

Comparison of the effects of intravenous alfentanil and esmolol on the cardiovascular response to double-lumen endobronchial intubation

We compared the effect of alfentanil 10 microg.kg-1 and esmolol 1.5 mg.kg-1 on the cardiovascular responses to laryngoscopy and double-lumen endobronchial intubation in two groups of 20 ASA 2-3 patients undergoing pulmonary surgery, in a randomised double-blind study. Arterial pressure and heart rate decreased after induction of anaesthesia and increased after intubation in both groups (p < 0.05) but remained at or below baseline values, and changes were comparable in both groups. Plasma catecholamine concentrations decreased after induction of anaesthesia in both groups (p < 0.05). Epinephrine concentrations increased in the esmolol group after intubation (p < 0.05) but remained below baseline in the alfentanil group (p < 0.05). Norepinephrine concentrations increased significantly in both groups after intubation but were higher in the esmolol group (p < 0.05). Although both esmolol 1.5 mg.kg-1 and alfentanil 10 microg.kg-1 similarly attenuated the arterial pressure and heart rate response to endobronchial intubation, plasma catecholamine concentrations increased in the esmolol group to values greater than previously reported after tracheal intubation.

The effect of clonidine premedication on hemodynamic responses to microlaryngoscopy and rigid bronchoscopy

The usual hemodynamic response to laryngoscopy and bronchoscopy is an increase in heart rate and arterial blood pressure. Previous work has reported that 10%-18% of the patients develop ischemic ST segment changes during the procedure. Therefore, we performed a prospective, randomized, double-blinded study in 36 patients scheduled for elective microlaryngeal and bronchoscopic surgical procedures to evaluate the effects of 300-microg oral clonidine premedication (n = 18) or placebo (n = 18) on the hemodynamic alterations and the incidence of perioperative myocardial ischemic episodes. Myocardial ischemia was assessed by using continuous electrocardiographic monitoring, beginning 30 min before, and lasting until 24 h after the operation. During the procedure, patients receiving placebo exhibited a significant increase (mean +/- SD) in arterial blood pressure (the systolic increasing from 137+/-11 to 166+/-17 mm Hg, the diastolic increasing from 80+/-11 to 97+/-14 mm Hg) and heart rate (increasing from 79+/-15 to 97+/-12 bpm) compared with the baseline and with the clonidine group. A dose of 300-microg clonidine blunted the hemodynamic response to endoscopy. Ventricular arrhythmias were more frequent in patients who were not premedicated with clonidine. Two patients in the control group, but none in the clonidine group, had evidence of myocardial ischemia. These data should encourage routine premedication with clonidine in patients undergoing microlaryngoscopic and bronchoscopic procedures.

Comparative evaluation of TIVA with propofol-fentanyl and thiopental-sevoflurane anesthesia using laryngeal mask airway for diagnostic bronchoscopy

PURPOSE

Diagnostic bronchoscopy is performed under general anesthesia in our hospital. This study was designed to determine whether total intravenous anesthesia (TIVA) with propofol-fentanyl provides more stable hemodynamics using a laryngeal mask airway (LMA) for diagnostic bronchoscopy than thiopental-sevoflurane anesthesia.

METHODS

Sixty patients scheduled for diagnostic bronchoscopy were randomly assigned to two groups. TIVA with propofol-fentanyl was induced with intravenous fentanyl 2 μg·kg^-1 and propofol 2 mg·kg^-1 and maintained with continuous infusion of propofol with fentanyl. Thiopental-sevoflurane anesthesia was induced with thiopental 5 mg·kg^-1 and maintained with N₂O/O₂/sevoflurane. Insertion of the LMA was facilitated with vecuronium 0.1 mg·kg^-1 i.v. in both groups. Ventilation was controlled, and administration of propofol and sevoflurane was continued until the end of the procedure. The LMA was removed when the patient was able to open his or her mouth.

RESULTS

During TIVA, the mean arterial pressure and rate pressure product decreased significantly from induction until 20 min after the start of the procedure, and they were maintained at around 70 mmHg and 7000, respectively, during the procedure. There were no significant differences in heart rate,[Formula: see text] and[Formula: see text]. In thiopental-sevoflurane anesthesia, the mean arterial pressure and rate pressure product decreased significantly after induction and increased significantly from insertion of the LMA until removal of the LMA. Heart rate increased significantly after insertion of the LMA, insertion of the bronchoscope, and removal of the LMA. There were no significant differences in[Formula: see text] and[Formula: see text].

CONCLUSION

TIVA with propofol-fentanyl in conjunction with an LMA performs better than thiopental-sevoflurane anesthesia for diagnostic bronchoscopy because of its superior maintenance of cardiovascular stability.

Haemodynamic and plasma catecholamine responses during total intravenous anaesthesia for laryngomicroscopy. Thiopentone compared with propofol

We compared the haemodynamic responses to endolaryngeal procedures during anaesthesia with propofol or thiopentone. Two minutes after administration of glycopyrronium 4 micrograms.kg-1 and alfentanil 17.5 micrograms.kg-1 anaesthesia was induced with either propofol 2.0 mg.kg-1 (n = 8) or thiopentone 5.0 mg.kg-1.min-1, respectively. Muscle relaxation was induced and maintained with suxamethonium. Intratracheal jet-ventilation (rate: 20 breath.min-1) was with 100% oxygen. Blood samples for later determination of plasma catecholamines were drawn and haemodynamic responses were recorded at tracheal intubation, after insertion of the operating laryngoscope, during the endolaryngeal procedure and after extubation. With both anaesthetic agents the only statistically significant haemodynamic response to intubation was a rise of heart rate. With propofol, plasma adrenaline concentrations decreased significantly after induction and remained below baseline values throughout the procedure. After insertion of the operating laryngoscope the haemodynamic response was more pronounced with thiopentone than with propofol. Propofol blocks the catecholamine and haemodynamic responses to endolaryngeal procedures more effectively than thiopentone.