Bronchial Mucus Transport Velocity Research Articles

Pressure-controlled ventilation-volume guaranteed mode improves bronchial mucus transport velocity in patients during laparoscopic surgery for gynecological oncology: a randomized controlled study

BackgroundMechanical ventilation during general anesthesia may impair airway mucosal function. This study aimed to investigate the effect of pressure-controlled ventilation-volume guaranteed (PCV-VG) on bronchial mucus transport velocity (BTV) in patients during laparoscopic surgery for gynecological oncology compared with volume controlled ventilation (VCV).Methods66 patients undergoing elective a laparoscopic surgery for gynecological oncology. The patients were randomized into two group receiving either PCV-VG or VCV. a drop of methylene blue was placed on the surface of the airway mucosa under the bronchoscopeand, then the distance the dye movement was measured after 2, 4, and 6 min. Outcomes were assessed at T0 (5 min after endotracheal intubation and before initiation of pneumoperitoneum), T1 and T2 (1 and 2 h after stabilization of pneumoperitoneum respectively). BTV at T0, T1 and T2 was the primary outcome. Secondary outcomes included heart rate (HR), mean arterial pressure (MAP), body temperature, end-tidal CO2 pressure (PETCO2), tidal volume(VT), peak inspiratory pressure (PIP), mean inspiratory pressure (Pmean), respiratory rate (RR), and dynamic compliance (CDyn) at T0, T1, and T2.Results64 patients were included in the analysis. The median [interquartile range] BTV was significantly lower in VCV group at T1 and T2 that at T0 (P < 0.05). Furthermore, BTV was slightly reduced in PCV-VG compared with VCV. BTV in PCV-VG was significantly decreased at T2 compared with BTV at T0 (P < 0.05) and slightly decreased at T1 compared with T0(P > 0.05). Compared with the PCV-VG group, BTV in VCV group significantly decreased at T2 (P < 0.05). No participants experienced respiratory complications.ConclusionsPCV-VG is more suitable for patients undergoing laparoscopic surgery for gynecological oncology than VCV since it can protect mucociliary clearance function.Trial registrationThis trial is registered on https://www.chictr.org.cn/ in Chinese Clinical Trial Registry (ChiCTR.2200064564: Date of registration 11/10/2022).

Effect of heated humidified ventilation on bronchial mucus transport velocity in general anaesthesia: a randomized trial.

To evaluate the effects of heated humidified ventilation on mucociliary function during general anaesthesia. Male patients (ASA physical status 1 or 2), scheduled for elective radical retropubic prostatectomy, were allocated to receive sevoflurane general anaesthesia with conventional or heated humidified ventilation. Bronchial mucus transport velocity was assessed via fibreoptic bronchoscope and methylene blue dye at 3h after induction of anaesthesia. Median (SE) bronchial mucus transport velocity was significantly higher in the heated humidified group (n = 26) than the conventional ventilation group (n = 24) (1.7 [0.3] mm/min vs 0.9 [0.1] mm/min). Heated humidified ventilation effectively maintains mucociliary clearance of patients during sevoflurane general anaesthesia.

Bronchial mucus transport velocity in patients receiving desflurane and fentanyl vs. sevoflurane and fentanyl

Sevoflurane has been shown to distinctly reduce bronchial mucus transport velocity, an essential determinant of mucociliary clearance and pulmonary complications. However, sevoflurane is regarded as one of the least irritant volatile anaesthetics, especially when compared with desflurane. Hence, the aim of this double-blind, randomized, controlled trial was to assess differences in bronchial mucus transport velocity between sevoflurane and desflurane. Twenty patients listed for general surgery were randomized to receive either maintenance of anaesthesia with desflurane and fentanyl, or sevoflurane and fentanyl. Thirty minutes after tracheal intubation, bronchial mucus transport velocity was assessed by fibreoptic observation of the movement of methylene blue dye applied to the dorsal surface of the right main bronchus. Both agents distinctly reduced bronchial mucus transport velocity when compared with previous studies, but the degree of impairment did not significantly differ between the investigated groups (median [25%/75% percentile]): desflurane 1.5 [0.5/4.2] vs. sevoflurane 1.3 [0.3/2.9] mm min(-1), P = 0.343). Desflurane is commonly regarded as more irritant to the airway, but as far as bronchial mucus transport velocity is concerned, the choice between sevoflurane and desflurane does not seem to matter.

Effect of smoking on bronchial mucus transport velocity under total intravenous anesthesia

The aim of this study was to measure the effect of smoking on bronchial mucus transport velocity with bronchoscope under total intravenous anesthesia. Methods: Twenty six ASA physical status I male patients (13 smokers and 13 nonsmokers) were enrolled into this study. They scheduled to undergo elective orthopedic surgery and were operated under total intravenous anesthesia using propofol and remifentanil. Single drop (approximately 0.02 cc) of methylene blue was applied to the posterior mucosal surface of right main bronchus 5 cm away from carina by the bronchoscope with epidural catheter 30 minutes after tracheal intubation. Two, four minutes after methylene blue application, the transport of methylene blue was observed. Six minutes after methylene blue application, the distance of methylene blue movement was measured. Results: Mean bronchial mucus transport distance and velocity of methylene blue in smoker group vs nonsmoker group was 9.1 ± 5.5 mm and 1.5 ± 1.0 mm/min vs 24.3 ± 15.2 mm and 4.1 ± 2.5 mm/min respectively. Mean bronchial mucus transport distance of methylene blue in the smoker group was shorter than that in the nonsmoker group (P value ＜ 0.05). Mean bronchial mucus transport velocity of methylene blue in the smoker group was slower than that in the nonsmoker group (P ＜ 0.05). Conclusions: Smoking may delay transport of bronchial secretion in terms of bronchial mucus transport velocity under total intravenous anesthesia.

Bronchial mucus transport velocity in patients receiving anaesthesia with propofol and morphine or propofol and remifentanil

In vitro morphine does not reduce cilia beat frequency, a key factor determining bronchial mucus transport velocity. There are no reports about the effect of remifentanil on bronchial mucus transport. We compared the bronchial mucus transport velocity in patients having total intravenous anaesthesia with either propofol and morphine, or propofol and remifentanil. Twenty patients scheduled for elective surgery were randomly allocated to the two groups. Fifteen minutes after insertion of the laryngeal mask airway, bronchial mucus transport velocity was assessed by fibreoptic observation of the movement of methylene blue dye applied to the right main bronchus. Compared with morphine, bronchial mucus transport velocity was significantly reduced in patients receiving remifentanil (morphine mean (SD) 9.2 (5.8) vs remifentanil 4.2 (3.0) mm.min(-1), p = 0.028). Anaesthesia with remifentanil may lead to significantly impaired bronchociliary clearance in comparison to morphine. This could have clinical implications, in particular in patients at risk.

Bronchial Mucus Transport Velocity in Patients Receiving Propofol and Remifentanil Versus Sevoflurane and Remifentanil Anesthesia

Volatile anesthetics reduce ciliary beat frequency in vitro. It has been reported that impaired bronchial mucus transport velocity (BTV) is associated with significantly increased pulmonary complications. In this study, we sought to determine in vivo differences in BTV, comparing patients having total IV anesthesia (TIVA) with propofol and remifentanil to anesthesia with sevoflurane and remifentanil. Twenty-two patients scheduled for elective general surgery were randomized to one of two groups: TIVA (propofol/remifentanil) or SEVO (sevoflurane/remifentanil). Thirty minutes after tracheal intubation, BTV was assessed by fiberoptic observation of the movement of methylene blue dye applied to the dorsal surface of the right main bronchus. BTV was significantly reduced in the SEVO group compared with the TIVA group (mean, 1.5 +/- 0.7 [0-2.3] versus 4.8 +/- 2.1 [2.3-8.8] mm/min; P < 0.0001). Anesthesia with sevoflurane may lead to significantly impaired bronchociliary clearance in comparison to TIVA. This could have implications for perioperative pulmonary complications, in particular in patients at risk for pulmonary complications.

Bronchial Mucus Transport Velocity in Paralyzed Anesthetized Patients: A Comparison of the Laryngeal Mask Airway and Cuffed Tracheal Tube

Bronchial Mucus Transport Velocity in Paralyzed Anesthetized Patients: A Comparison of the Laryngeal Mask Airway and Cuffed Tracheal Tube

Bronchial Mucus Transport Velocity in Paralyzed Anesthetized Patients

We compared bronchial mucus transport velocity (BTV), an index of mucociliary clearance, between the laryngeal mask airway (LMA) and the tracheal tube (TT).Forty patients were studied during propofol anesthesia and muscle relaxation with rocuronium. BTV was measured 10 and 60 min after insertion of the airway device by fiberoptic observation of the movement of methylene blue dye injected onto the dorsal surface of the left main bronchus. BTV for the LMA was similar at 10 and 60 min (13.9 +/- 2.0 and 13.6 +/- 2.1 mm/min, respectively). BTV for the TT was significantly faster at 10 min that at 60 min (13.0 +/- 1.4 vs 6.9 +/- 1.2 mm/min, respectively; P < 0.00001). BTV was similar for both devices at 10 min (TT 13.0 +/- 1.4 mm/min versus LMA 13.9 +/- 2.0 mm/min), but was significantly faster for the LMA than for the TT at 60 min (LMA 13.6 +/- 2.1 mm/min versus TT 6.9 +/- 1.2 mm/min; P < 0.00001). We conclude that the LMA impedes mucociliary clearance less than the TT in anesthetized patients. This may have implications for reducing the risk of retention of secretions, atelectasis, and pulmonary infection. Implications: This study compares bronchial mucus transport velocity, an index of mucociliary clearance, in anesthetized patients between two airway devices, the cuffed tracheal tube and the laryngeal mask airway. We have shown that the laryngeal mask airway impairs mucociliary clearance less than the tracheal tube. This may have implications for reducing the risk of retention of secretions, atelectasis, and pulmonary infection. (Anesth Analg 1998;86:1280-2)

Ultrastructure and mucociliary transport of bronchial respiratory epithelium in intubated patients.

The objective of this study was to investigate whether reduced bronchial mucus transport velocity (BTV) is associated with a loss of cilia or ultrastructural abnormalities of cilia in intubated patients. The patients were studied prospectively in a convenience sample trial. The study took place in a university hospital. 29 orally intubated patients in a surgical ICU. BTV was measured with radiolabeled microspheres in the right and left primary bronchus. Following these measurements, biopsy samples were taken from the bronchi for scanning (SEM) and transmission (TEM) electron-microscopic investigations. SEM: Patients with normal or slight impaired BTV (group 1, n = 14: BTV: 8.5 mm/min (3.8-11.5); median with range) showed more cilia on the luminal surface than patients with markedly depressed BTV (p < 0.05) (group 2, n = 15: BTV: 0 (0-2.1)). The difference was statistically significant. The BTV values correlated moderately with the number of cilia on the luminal surface (r = 0.46; p = 0.02). TEM: In group 1, 6.5% (3.9-14.9) of cilia were abnormal (median with range) vs 9.3% (4.9-13.7) in group 2; these differences were not statistically significant. Neither was there any significant correlation between BTV and the frequency of abnormal cilia. Impaired mucociliary transport in intubated patients is associated with a loss of cilia rather than ultrastructural abnormalities of cilia, which are less relevant.

Bronchial mucus transport in chronic smokers and nonsmokers during general anesthesia

Study Objective: To compare bronchial mucus transport velocity in smokers and nonsmokers. Design: Prospective consecutive-sample trial. Setting: University hospital. Patients: 12 smokers and 22 nonsmokers undergoing major abdominal or thoracic surgery with postoperative mechanical ventilation. Interventions: After the end of the operation, bronchial mucus transport velocity was measured with a small volume (0.05 to 0.08 ml) of technetium 99-m labeled albumin microspheres with an activity of 1.5 MBq. The radiolabeled bolus was deposited on the dorsal mucosal surface at the distal end of the right and left main bronchus via flexible bronchoscopy. The movement of the microspheres toward the trachea was visualized and recorded using a scintillation camera. Quantitative evaluation was based on the pathtime diagram. After determination of bronchial mucus transport velocity, patients were examined daily over 4 days to record pulmonary complications (retention of secretion and nosocomial pneumonia). Measurements and Main Results: Smokers were comparable to nonsmokers with respect to age, preoperative lung function tests, body temperature, duration of mechanical ventilation, dose of anesthetics, and intraoperative blood loss. Smokers had a significantly slower bronchial mucus transport velocity compared with nonsmokers: in the left bronchus, 1.3 mm/min (0 to 9.6 mm/min) (median with range) versus 9.7 mm/min (3.7 to 15.3 mm/min) ( p < 0.001); in the right bronchus, 2.5 mm/min (0 to 16.0 mm/min) versus 8.3 mm/min (5.5 to 15.3 mm/min) ( p < 0.01). Pulmonary complications occurred in 4 smokers and 1 nonsmoker. Conclusions: When measured during general anesthesia, smokers have a slower bronchial mucus transport than nonsmokers. This may be related to postoperative pulmonary complications in smokers.

Measurement of Mucociliary Transport Velocity in Ventilated Patients: Short-term Effect of General Anesthesia on Mucociliary Transport

The objectives of this study were to evaluate a method for measuring BTV in ventilated patients and to study the short-term effect of general anesthesia with midazolam, Fentanyl, pancuronium and O2:N2O on BTV. The study included phantom measurements on a bronchoscopy model and the determination of BTV in patients in a convenience sample trial. The study took place in a university hospital. Fourteen patients undergoing major abdominal surgery with planned postoperative mechanical ventilation were included in the study. All patients gave their written informed consent to participate in the study. Bronchial mucus transport velocity was measured with a small volume (0.05 to 0.08 ml) of technetium 99m-labeled albumin microspheres with an activity of 3 MBq. The radiolabeled bolus was deposited on the dorsal mucosal surface at the distal end of the right and left main bronchus via flexible bronchoscopy. The movement of the microspheres toward the trachea was visualized and recorded using a scintillation camera; quantitative evaluation utilized the condensed image. The technique was validated in a bronchoscopy model and in an intubated patient by moving a radioactive drop in a catheter through the main bronchi at velocities from 0 to 20 mm/min. The velocities determined by the image processing technique correlated well with the data by the model and patient determination (right bronchus, r = 1.0; left bronchus, r = 1.0). In seven ventilated patients, mechanical irritation by the fiberscope produced no significant effect on BTV. The BTV was measured preoperatively in seven conscious patients one day before surgery while they received local anesthesia with 10 ml of 1 percent lidocaine and postoperatively while they received intubation anesthesia. The preoperative and postoperative BTV values showed no significant differences (10.5; 5.7 to 13.7 mm/min; vs 9.7 (3.7 to 15.3) (median with range). By this method, bronchial transport velocity can be determined in a relatively short time in ventilated patients. General anesthesia with midazolam, Fentanyl, pancuronium and O2:N2O does not influence BTV.