Sedation during bronchoscopy: data from a nationwide sedation and monitoring survey

A study of hemodynamic effects, postoperative recovery, and safety of esketamine (right handed) during flexible bronchoscopy under general anesthesia

OBJECTIVE

Flexible bronchoscopy during general anesthesia has become an indispensable tool. Anesthetics are widely utilized in flexible bronchoscopy (FB). This study delved into the application value of a subanesthetic dose of esketamine (ES) (right handed) in flexible bronchoscopy during general anesthesia.

METHODS

A sample of 160 patients who underwent flexible bronchoscopy during general anesthesia were selected as study subjects and were equally divided into the control and ES groups, with clinical baseline data (age, sex, body mass index, American Society of Anesthesiologists grading) collected. Hemodynamic parameters (mean artery pressure, heart rate, pulse blood oxygen saturation) at different time points, the onset time of anesthesia, surgery time, analgesia maintenance time, anesthesia awakening time, and perioperative adverse reactions were recorded. Visual analogue scale (VAS), Mini-Mental State Examination (MMSE), and quality of recovery-40 (QoR-40) scales were utilized for assessing post-surgery satisfaction, cognitive function, and post-surgery early recovery quality.

RESULTS

The hemodynamics were stable at each time point, but patients in the ES group were more stable than those in the control group. Patients in the ES group exhibited faster onset and awakening time of anesthesia, longer duration of analgesia, and lower total incidence of adverse reactions versus the control group. The patients' QoR-40 total scores in the ES group were improved versus the control group at 1 day after surgery.

CONCLUSION

Compared with fentanyl, the use of ES (right handed) in flexible bronchoscopy during general anesthesia produces more stable hemodynamics, faster onset and recovery time of anesthesia, longer duration of analgesia, lower incidence of adverse reactions, and improved early postoperative recovery quality in patients.

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.

Clinical usefulness of nebulized dexmedetomidine for conscious sedation in daycare flexible bronchoscopy in Southern India

BACKGROUND

Sedative agents used in bronchoscopy require trained personnel to administer and monitor the patient. This increases the procedure cost, duration, and inpatient stay. Inhalational administration of sedative agents can be a practical solution to the issue. Dexmedetomidine in the inhalational form could give results similar to the intravenous form without significant adverse events.

MATERIALS AND METHODS

The study is prospective, randomized, and double-blinded study. Patients needing bronchoscopy were randomized to receive the nebulized form of either dexmedetomidine or saline (0.9%) before bronchoscopy. The study parameters are assessed and recorded before, during, and after bronchoscopy. Data collected are analyzed using the SPSS software.

DISCUSSION

The side effects limit using commonly administered sedation agents in bronchoscopy, such as midazolam, fentanyl, and dexmedetomidine. The nebulized dexmedetomidine is safe with proven efficacy when compared to the placebo. Proceduralist-administered conscious sedation reduces the overall cost and shortens inpatient stays. Attenuation of hemodynamic parameters by dexmedetomidine could be an advantage for the physician in reducing an untoward cardiac event.

CONCLUSION

Dexmedetomidine in the nebulized form improves the comfort of patients during the procedure. It blunts the pressure response during bronchoscopy and could be a safer and cost-effective agent in its nebulized form for conscious sedation in bronchoscopy. The study is approved by the institutional ethics committee (IEC KMC MLR 10-2021-310).

Transcutaneous gas monitoring is a useful tool to detect respiratory depression during bronchoscopy performed under propofol sedation

BACKGROUND

Bronchoscopy is a relatively invasive procedure where patients are often sedated. However, adequate sedation is not always achieved. Propofol is often used for difficult-to-sedate patients undergoing bronchoscopy despite a potential risk of respiratory depression. Transcutaneous carbon dioxide (tcpCO2) monitoring, introduced recently, is recognized as a convenient surrogate method for continuous monitoring of the partial pressure of arterial carbon dioxide (PaCO2). This study examined the safety of switching to propofol during bronchoscopy by using transcutaneous carbon dioxide monitoring.

METHODS

Patients in whom transcutaneous gas monitoring had been performed during bronchoscopy were included in this study. The participants were divided into two groups: 1) the midazolam + fentanyl group (MF group), and 2) the group in which midazolam was switched to propofol owing to inadequate sedation obtained with midazolam + fentanyl (MFP group). We retrospectively analyzed the transcutaneous gas measurement data collected in patients under propofol sedation for bronchoscopy.

RESULTS

This study included 61 (MF, n = 41; MFP, n = 20) patients. The duration of elevated tcpCO2 (>50 mm Hg) was greater in the MFP group (MF 8.5 min vs. MFP 22.1 min, p = 0.042).

CONCLUSION

Switching midazolam to propofol during bronchoscopy was significantly associated with a higher risk of elevated tcpCO2, which is indicative of respiratory depression. Therefore, continuous tcpCO2 monitoring is required to ensure the safety of patients under propofol sedation for bronchoscopy.

Dextromethorphan premedication in the alleviation of cough during flexible bronchoscopy in adults: A randomized double-blind placebo-controlled trial

BACKGROUND AND OBJECTIVE

Cough is invariably encountered during flexible bronchoscopy despite sedation and topical anaesthetics. The ideal cough suppressant during flexible bronchoscopy is not known. We assessed the role of dextromethorphan premedication in relieving the cough during flexible bronchoscopy in adults.

METHODS

In this single-centre study, we randomized patients aged ≥18 years to receive dextromethorphan syrup 30 ml (90 mg) or an equal volume of placebo 1 h before the procedure. Patients rated their cough severity and discomfort on a visual analogue scale at the end of the procedure. Bronchoscopists also rated cough severity at the end of the procedure.

RESULTS

Out of 112 patients screened, 94 patients (median (interquartile range [IQR]) age 51 (36.25-60.75) years, male: female 2.13:1) were randomized to either the dextromethorphan (n = 47) or placebo (n = 47) groups. The patients-rated median (IQR) cough scores at the end of the procedure were 15 (10-23) mm in dextromethorphan versus 20 (12-45.5) mm in placebo groups (p = 0.03). Patients-rated median cough scores at 1 h (5 mm vs. 6 mm, p = 0.21), discomfort scores (12.5 mm vs. 12.5 mm, p = 0.49), and midazolam and lignocaine usage were similar between the two groups. The bronchoscopist-rated median cough score was non-significantly lower in the intervention compared to the placebo (26 mm vs. 35 mm, p = 0.09) groups.

CONCLUSION

Dextromethorphan premedication 1 h before flexible bronchoscopy may have an additive effect on cough suppression under conscious sedation and topical lignocaine. Further trials are needed to reiterate our findings with certainty.

Procedural analgesic interventions in China: a national survey of 2198 hospitals

Background

Humane treatment requires the provision of appropriate sedation and analgesia during medical diagnosis and treatment. However, limited information is available about the status of procedural analgesic interventions in Chinese hospitals. Therefore, a nationwide survey was established to identify challenges and propose potential improvement strategies.

Methods

Forty-three members of the Pain Group of Chinese Society of Anesthesiology established and reviewed the questionnaire, which included (1) general information on the hospitals, (2) the sedation/analgesia rate in gastrointestinal endoscopy, labor, flexible bronchoscopy, hysteroscopy in China, (3) staff assignments, (4) drug use for procedural analgesic interventions, and (5) difficulties in procedural analgesic interventions. The data were obtained using an online questionnaire sent to the chief anesthesiologists of Chinese hospitals above Grade II or members of the Pain Group of Chinese Society of Anesthesiology.

Results

Valid and complete questionnaires were received from 2198 (44.0%) hospitals, of which 64.5% were Grade III. The overall sedation/analgesia rates were as follows: gastroscopy (50.6%), colonoscopy (53.7%), ERCP (65.9%), induced abortion (67.5%), labor (42.3%), hysteroscopy (67.0%) and fiber bronchoscopy (52.6%). Compared with Grade II hospitals, Grade III hospitals had a higher proportion of procedural analgesic interventions services except for induced abortion. On average (median [IQR]), each anesthesiologist performed 5.7 [2.3—11.4] cases per day, with 7.3 [3.2—13.6] performed in Grade III hospitals and 3.4 [1.8—6.8] performed in Grade II hospitals (z = -7.065, p < 0.001).

Conclusions

Chinese anesthesiologists have made great efforts to achieve procedural analgesic interventions, as evidenced by the increased rate. The uneven health care provided by hospitals at different levels and in different regions and the lack of anesthesiologists are the main barriers to optimal procedural analgesic interventions.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-022-01783-6.

High-flow Nasal Oxygen Versus Standard Oxygen During Flexible Bronchoscopy in Lung Transplant Patients: A Randomized Controlled Trial

BACKGROUND

Diagnostic and interventional flexible bronchoscopy (FB) is increasingly utilized in complex and high-risk patients. Patients are often sedated for comfort and procedure facilitation and hypoxia is commonly observed in this setting. We hypothesized that high-flow nasal oxygen (HFNO) would reduce the incidence of patients experiencing oxygen desaturation.

METHODS

In this randomized controlled trial, postlung transplant patients booked for FB with transbronchial lung biopsy were assigned to either HFNO or low-flow nasal oxygen (LFNO). The patient and bronchoscopist were blinded to group allocation. The primary endpoint was the proportion of patients experiencing mild desaturation [peripheral oxygen saturation (SpO2)<94%]. Secondary endpoints included desaturation (SpO2<90%), the number of airway interventions required and procedure interruptions, the duration of oxygen desaturation and patient, bronchoscopist and anesthesiologist satisfaction scores.

RESULTS

The trial analyzed data from 76 patients (LFNO, n=39; HFNO, n=37). HFNO reduced the proportion of patients experiencing SpO2<94% (43.2% vs. 89.7%, P<0.001) and SpO2<90% (16.2% vs. 69.2%, P<0.001). The FB was interrupted 11 times in 9 patients in the LFNO group, whereas there were no interruptions in the HFNO group. There were no differences in patient and bronchoscopist satisfaction scores between groups, anesthesiologists had higher satisfaction scores when using HFNO (P<0.001).

CONCLUSION

Hypoxia occurred less commonly in postlung transplant patients receiving HFNO during FB. Further studies are warranted in other high-risk populations undergoing longer duration FB.

Hypercapnia in COPD Patients Undergoing Endobronchial Ultrasound under Local Anaesthesia and Analgosedation: A Prospective Controlled Study Using Continuous Transcutaneous Capnometry

BACKGROUND

Flexible bronchoscopy (FB) in analgosedation causes alveolar hypoventilation and hypercapnia, the more so if patients suffer from COPD. Nonetheless, neither is capnometry part of standard monitoring nor is there evidence on how long patients should be monitored after sedation.

OBJECTIVES

We investigated the impact of COPD on hypercapnia during FB with endobronchial ultrasound (EBUS) in sedation and how the periprocedural monitoring should be adapted.

METHODS

Two cohorts of consecutive patients - with advanced and without COPD - with the indication for FB with EBUS-guided transbronchial needle aspiration in analgosedation received continuous transcutaneous capnometry (ptcCO2) before, during, and for 60 min after the sedation with midazolam and alfentanil.

MAIN RESULTS

Forty-six patients with advanced COPD and 44 without COPD were included. The mean examination time was 26 ± 9 min. Patients with advanced COPD had a higher peak ptcCO2 (53.7 ± 7.1 vs. 46.8 ± 4.8 mm Hg, p < 0.001) and mean ptcCO2 (49.5 ± 6.8 vs. 44.0 ± 4.4 mm Hg, p < 0.001). Thirty-six percent of all patients reached the maximum hypercapnia after FB in the recovery room (8 ± 11 min). Patients with COPD needed more time to recover to normocapnia (22 ± 24 vs. 7 ± 11 min, p < 0.001). They needed a nasopharyngeal tube more often (28 vs. 11%, p < 0.001). All patients recovered from hypercapnia within 60 min after FB. No intermittent ventilation manoeuvres were needed.

CONCLUSION

A relevant proportion of patients reached their peak-pCO2 after the end of intervention. We recommend using capnometry at least for patients with known COPD. Flexible EBUS in analgosedation can be safely performed in patients with advanced COPD. For patients with advanced COPD, a postprocedural observation time of 60 min was sufficient.

Using structured progress to measure competence in flexible bronchoscopy

Background

Flexible bronchoscopy is a core invasive procedure in pulmonary medicine and training in the procedure is mandatory. Diagnostic completeness and procedure time have been identified as useful measures of competence. No outcome measures have been developed regarding navigational path in bronchoscopy to assess whether the bronchial segments have been identified in an arbitrary or structured order. We investigated whether a new outcome measure for structured progression could be used to assess competency in flexible bronchoscopy.

Methods

The study was designed as a prospective comparative study. Twelve novices, eleven intermediates, and ten expert bronchoscopy operators completed three full bronchoscopies in a simulated setting on a phantom. The following outcome measures were collected through a checklist evaluation by a trained rater: Diagnostic Completeness as amount of visualized bronchial segments, Structured Progress between the bronchial segments in ascending order, and average intersegmental time (AIT).

Results

The ability to follow a structured ascending path through the bronchial tree correlated with a higher amount of identified bronchial segments (Pearson’s correlation, r=0.62, P<0.001) and a lower AIT (Pearson’s correlation, r=−0.52, P<0.001).

Conclusions

Operators should advance through the bronchial tree in a structured ascending order to ensure systematic progress with the highest level of diagnostic yield and the lowest procedure time. Structured progression is a useful measure to evaluate competency in flexible bronchoscopy.

Sedation for bronchoscopy: current practices in Latin America

Objective:

To evaluate current practices in sedation for bronchoscopy in Latin America.

Methods:

This was an anonymous survey of select members of the Latin American Thoracic Association. The questionnaire, made available online from November of 2015 through February of 2016, was designed to collect data on demographic characteristics; type of facility (public or private); type/volume of bronchoscopies; type of sedation; and type of professional administering the sedation.

Results:

We received 338 completed questionnaires from 19 countries; 250 respondents (74.0%) were male. The mean respondent age was 36.0 ± 10.5 years. Of the 338 respondents, 304 (89.9%) were pulmonologists; 169 (50.0%) worked at public facilities; and 152 (45.0%) worked at teaching facilities. All of the respondents performed diagnostic fiberoptic bronchoscopy, 206 (60.9%) performed therapeutic fiberoptic bronchoscopy, 125 (37.0%) performed rigid bronchoscopy, 37 (10.9%) performed endobronchial ultrasound, and 3 (0.9%) performed laser therapy/thermoplasty/cryotherapy. Sedation for bronchoscopy was employed by 324 respondents (95.6%). Of the 338 respondents, 103 (30.5%) and 96 (28.4%) stated, respectively, that such sedation should “usually” and “never” be administered by a bronchoscopist; 324 (95.9%) supported training bronchoscopists in sedation. Sedation administered by a bronchoscopist was reported by 113 respondents, conscious sedation being employed by 109 (96.2%). The use of benzodiazepines, propofol, and opiates was reported, respectively, by 252 (74.6%), 179 (52.9%), and 132 (39.0%) of the 338 respondents. Deep sedation and general anesthesia were more common at private facilities.

Conclusions:

The consensus seems to be that a well-trained bronchoscopist can safely administer sedation for bronchoscopy. However, approximately 40% of bronchoscopists do not do so regularly.

Analgosedation during flexible fiberoptic bronchoscopy: comparing the clinical effectiveness and safety of remifentanil versus midazolam/propofol

Background

There are limited data regarding the efficacy and safety of remifentanil sedation for diagnostic bronchoscopy. The aim of this study was to evaluate the clinical efficacy and safety of remifentanil by comparing it with those of conventional drugs, midazolam and propofol.

Methods

A retrospective study of 186 patients who underwent diagnostic bronchoscopy at Chonbuk National University Hospital was performed. Patients were classified into the remifentanil group and midazolam/propofol group according to the drugs used during bronchoscopy.

Results

Of the 186 patients, 111 patients received remifentanil and 75 received midazolam/propofol during the bronchoscopy. The proportion of patients who required bronchoscopy for endobronchial inspection alone was significantly higher in the midazolam/propofol group than in the remifentanil group (93.3% vs. 73.0%; p <  0.001). In contrast, the proportion of patients who required more invasive procedures, such as bronchoscopic biopsy, bronchoalveolar lavage, or transbronchial lung biopsy, was significantly higher in the remifentanil group than in the midazolam/propofol group (27.0% vs. 6.7%; p <  0.001). The recovery time was significantly shorter in the remifentanil group than in the midazolam/propofol group (mean 6.4 min vs. 11.6 min, p <  0.001). There were no significant differences between the groups with regard to safety events including desaturation, hypotension, and arrhythmia.

Conclusions

Despite the higher proportion of patients who underwent more invasive procedures in the remifentanil group than in the midazolam/propofol group, there was no significant difference in safety events between the groups. Those in the remifentanil group also demonstrated a faster recovery time than those in the midazolam/propofol group.

Guidelines for diagnostic flexible bronchoscopy in adults: Joint Indian Chest Society/National College of chest physicians (I)/Indian association for bronchology recommendations

Flexible bronchoscopy (FB) is commonly performed by respiratory physicians for diagnostic as well as therapeutic purposes. However, bronchoscopy practices vary widely across India and worldwide. The three major respiratory organizations of the country supported a national-level expert group that formulated a comprehensive guideline document for FB based on a detailed appraisal of available evidence. These guidelines are an attempt to provide the bronchoscopist with the most scientifically sound as well as practical approach of bronchoscopy. It involved framing appropriate questions, review and critical appraisal of the relevant literature and reaching a recommendation by the expert groups. The guidelines cover major areas in basic bronchoscopy including (but not limited to), indications for procedure, patient preparation, various sampling procedures, bronchoscopy in the ICU setting, equipment care, and training issues. The target audience is respiratory physicians working in India and well as other parts of the world. It is hoped that this document would serve as a complete reference guide for all pulmonary physicians performing or desiring to learn the technique of flexible bronchoscopy.

Hypoventilation patterns during bronchoscopic sedation and their clinical relevance based on capnographic and respiratory impedance analysis

Capnography involves the measurement of end-tidal CO₂ (EtCO₂) values to detect hypoventilation in patients undergoing sedation. In a previous study, we reported that initiating a flexible bronchoscopy (FB) examination only after detecting signs of hypoventilation could reduce the risk of hypoxemia without compromising the tolerance of the patient for this type of intervention. We hypothesize that hypoventilation status could be determined with greater precision by combining thoracic impedance-based respiratory signals, RESP, and EtCO₂ signals obtained from a nasal-oral cannula. Retrospective analysis was conducted on RESP and EtCO₂ waveforms obtained from patients during the induction of sedation using propofol for bronchoscopic examination in a previous study. EtCO₂ waveforms associated with hypoventilation were then compared with RESP patterns, patient variables, and sedation outcomes. Signals suitable for analysis were obtained from 44 subjects, 42 of whom presented indications of hypoventilation, as determined by EtCO₂ waveforms. Two subtypes of hypoventilation were identified by RESP: central-predominant (n = 22, flat line RESP pattern) and non-central-predominant (n = 20, RESP pattern indicative of respiratory effort with upper airway collapse). Compared to cases of non-central-predominant hypoventilation, those presenting central-predominant hypoventilation during induction were associated with a lower propofol dose (40.2 ± 18.3 vs. 60.8 ± 26.1 mg, p = 0.009), a lower effect site concentration of propofol (2.02 ± 0.33 vs. 2.38 ± 0.44 µg/ml, p = 0.01), more rapid induction (146.1 ± 105.5 vs. 260.9 ± 156.2 s, p = 0.01), and lower total propofol dosage (96.6 ± 41.7 vs. 130.6 ± 53.4 mg, p = 0.04). Hypoventilation status (as revealed by EtCO₂ levels) could be further classified by RESP into central-predominant or non-central-predominant types. It appears that patients with central-predominant hypoventilation are more sensitive to propofol during the induction of sedation. RESP values could be used to tailor sedation management specifically to individual patients.

Sedation for advanced procedures in the bronchoscopy suite: proceduralist or anesthesiologist?

PURPOSE OF REVIEW

This article focuses on the issue of sedation provided either by proceduralists or anesthesiologists for advanced bronchoscopy procedures. The relative merits of both approaches are presented. Current evidence from the literature and guideline recommendations relevant to this topic are reviewed.

RECENT FINDINGS

In general, patient and proceduralist satisfaction as well as patient safety are increased when intravenous sedation is provided for advanced bronchoscopic procedures. However, guidelines by various societies remain vague on defining the appropriate level of care required when providing sedation for these procedures. In addition, targeted depth of sedation varies considerably among practitioners. While in some settings, nonanesthesiologist-administered propofol sedation has been proven safe; nevertheless, its use is controversial, especially in the bronchoscopy suite.

SUMMARY

The role of the anesthesiologist in sedation for advanced bronchoscopy remains undefined. When deep sedation for prolonged interventional procedures is needed or when dealing with patients who have multiple comorbidities, an anesthesiologist should be involved.

Anesthesia for interventional pulmonology procedures: a review of advanced diagnostic and therapeutic bronchoscopy

PURPOSE

Interventional pulmonology is a growing subspecialty of pulmonary medicine with flexible and rigid bronchoscopies increasingly used by interventional pulmonologists for advanced diagnostic and therapeutic purposes. This review discusses different technical aspects of anesthesia for interventional pulmonary procedures with an emphasis placed on pharmacologic combinations, airway management, ventilation techniques, and common complications.

SOURCE

Relevant medical literature was identified by searching the PubMed and Google Scholar databases for publications on different anesthesia topics applicable to interventional pulmonary procedures. Cited literature included case reports, original research articles, review articles, meta-analyses, guidelines, and official society statements.

PRINCIPAL FINDINGS

Interventional pulmonology is a rapidly growing area of medicine. Anesthesiologists need to be familiar with different considerations required for every procedure, particularly as airway access is a shared responsibility with pulmonologists. Depending on the individual case characteristics, a different selection of airway method, ventilation mode, and pharmacologic combination may be required. Most commonly, airways are managed with supraglottic devices or endotracheal tubes. Nevertheless, patients with central airway obstruction or tracheal stenosis may require rigid bronchoscopy and jet ventilation. Although anesthetic approaches may vary depending on factors such as the length, complexity, and acuity of the procedure, the majority of patients are anesthetized using a total intravenous anesthetic technique.

CONCLUSIONS

It is fundamental for the anesthesia provider to be updated on interventional pulmonology procedures in this rapidly growing area of medicine.

End-tidal capnographic monitoring to detect apnea episodes during flexible bronchoscopy under sedation

Background

Apnea developing as a result of oversedation is a potential clinical problem in patients undergoing flexible bronchoscopy (FB) under sedation. However, there are no reports of evaluation using a standardized method of the frequency of occurrence of apnea episodes during FB under sedation. The aim of this study was to investigate the frequency of apnea episodes during FB under sedation in the clinical setting by end-tidal capnography.

Methods

This study was a single-institution retrospective review of a prospectively maintained database and medical records, including capnographic data, from April 2015 to March 2016. We enrolled patients who were sedated with midazolam and underwent diagnostic FB under end-tidal capnographic monitoring. Apnea was defined as cessation of airflow for more than 10 s.

Results

Data from a total of 121 eligible patients were analyzed. A total of 131 apnea episodes (median duration 33 s) were recorded in 59 patients (48.8%). Prolonged apnea episodes lasting for more than 30 s occurred in 24 patients (19.8%). Furthermore, 55 apnea episodes (42.0%) were followed by a decline of the SpO₂ by ≥4% from the baseline.

Conclusions

In this study, end-tidal capnography revealed the occurrence of apnea episodes at a high frequency in patients undergoing FB under sedation in the clinical setting.