Myocardial ischemia in sedated patients undergoing fiberoptic bronchoscopy

Safety of Bronchoscopy after Acute Coronary Syndrome

<b><i>Background:</i></b> Bronchoscopy is a safe procedure which is frequently performed for the investigation of respiratory diseases. Current guidelines recommend to delay bronchoscopy for 4–6 weeks after acute coronary syndrome (ACS), as this period is theoretically considered at risk for new onset of ACS. We therefore aimed to evaluate the safety and the tolerance of bronchoscopy in patients with ACS (≤30 days) and to compare outcomes with matched controls. <b><i>Methods:</i></b> All consecutive patients who had a bronchoscopy performed in the first 30 days after an ACS in the bronchoscopy suite were included. A group of patients with ACS who did not undergo bronchoscopy (controls) were also included and matched for age, sex, type of ACS, and severity of ACS (GRACE score). <b><i>Results:</i></b> Of the 13,646 patients who underwent bronchoscopy between 2010 and 2019, 2,181 had an history of ACS and among those, 87 patients had an ACS (19 with STEMI, 52 with NSTEMI, and 16 unstable angina). Mean interval between ACS and bronchoscopy was of 10.1 ± 8.9 days. Systolic blood pressure and heart rate significantly increased and oxygen saturation significantly decreased during bronchoscopy. The most frequent adverse event was desaturation which occurred in 26% of patients. Reinfarction rate (1.1% vs. 2.3% <i>p</i> = 1.00) and all-cause 30-day mortality (2.3% vs. 4.6%; <i>p</i> = 0.68) were similar in patients who underwent bronchoscopy and in matched controls (<i>n</i> = 87). <b><i>Conclusion:</i></b> Our study reinforces the safety of bronchoscopy after ACS. When clinically indicated with potential benefits outweighing risks, ACS should not contraindicate bronchoscopy.

Complications of bronchoscopy: A concise synopsis

Flexible and rigid bronchoscopes are used in diagnosis, therapeutics, and palliation. While their use is widespread, effective, and generally safe; there are numerous potential complications that can occur. Mechanical complications of bronchoscopy are primarily related to airway manipulations or bleeding. Systemic complications arise from the procedure itself, medication administration (primarily sedation), or patient comorbidities. Attributable mortality rates remain low at < 0.1% for fiberoptic and rigid bronchoscopy. Here we review the complications (classified as mechanical or systemic) of both rigid and flexible bronchoscopy in hope of making practitioners who are operators of these tools, and those who consult others for interventions, aware of potential problems, and pitfalls in order to enhance patient safety and comfort.

Intravenous Dexmedetomidine Provides Superior Patient Comfort and Tolerance Compared to Intravenous Midazolam in Patients Undergoing Flexible Bronchoscopy

Dexmedetomidine, an α2 agonist, has demonstrated its effectiveness as a sedative during awake intubation, but its utility in fiberoptic bronchoscopy (FOB) is not clear. We evaluated the effects of midazolam and dexmedetomidine on patient's response to FOB. The patients received either midazolam, 0.02 mg/kg (group M, n=27), or dexmedetomidine, 1 µg/kg (group D, n=27). A composite score of five different parameters and a numerical rating scale (NRS) for pain intensity and distress were used to assess patient response during FOB. Patients rated the quality of sedation and level of discomfort 24 h after the procedure. Ease of bronchoscopy, rescue medication requirement, and haemodynamic variables were noted. Ideal or acceptable composite score was observed in 15 and 26 patients, respectively, in group M (14.48±3.65) and group D (9.41±3.13), p<0.001. NRS showed that 11 patients in group M had severe pain and discomfort as compared to one patient with severe pain and two with severe discomfort in group D during the procedure, p<0.001. Rescue midazolam requirement was significantly higher in group M (p=0.023). We conclude that during FOB, under topical airway anaesthesia, IV dexmedetomidine (1 µg/kg) provides superior patient comfort and tolerance as compared to IV midazolam (0.02 mg/kg).

Safety of interventional bronchoscopy through complication review at a cancer center

BACKGROUND AND AIMS

There have been rapid advances in the area of interventional bronchoscopy over the past 15 years, but associated complications have been rarely discussed. A longitudinal evaluation of the same operator's performance at a cancer center is reported.

METHODS

A detailed record review of diagnostic and therapeutic bronchoscopy between January 1997 and March 2013 was conducted.

RESULTS

Among the 1358 diagnostic bronchoscopies, there were nine major complications requiring premature termination and three pneumothoraces found during follow-up (0.88%). An escalation in the level of care was required for four patients with massive bleeding, asthma attack, sedation intoxication and myocardial ischemia, respectively. Six cases occurred after brushing (0.71%), and five cases before any sampling procedure was conducted. The complication rate was highest for peripheral lesions (1.03%). Among the 109 therapeutic bronchoscopies, no major patient-specific complication occurred except for excessive granulation tissue formation following metallic stenting in one patient with benign tracheal stenosis.

CONCLUSION

The complication rate with regard to bronchoscopy is comparable with historical controls according to the related literature, and their occurrence appears to be sporadic, not relevant to patient characteristics and mostly related to the bronchoscopy itself rather than the introduction of new techniques. Bronchoscopy remains safe along with technical innovations. However, risk recognition and effective prevention is essential.

Flexible bronchoscopy

Although bronchoscopy technology continues to evolve at a fairly rapid pace, basic procedures, such as bronchoalveolar lavage, transbronchial lung biopsy, and transbronchial needle aspiration, continue to play a paramount role in the diagnosis of bronchopulmonary diseases. Pulmonologists should be trained in these basic bronchoscopic procedures.

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.

Predictors of atelectasis after pulmonary lobectomy

PURPOSE

To define the incidence of and factors predisposing to postlobectomy atelectasis (PLA).

METHODS

The subjects were 412 patients who underwent pulmonary lobectomy at our hospital between January 2004 and April 2007. This study was performed as a retrospective analysis of our prospective database. Postlobectomy atelectasis was defined as ipsilateral opacification of the involved lobe or segment with an ipsilateral shift of the mediastinum on chest radiograph, requiring bronchoscopy.

RESULTS

Postlobectomy atelectasis developed in 27 patients (6.6%), accounting for 29% of all postoperative pulmonary complications. There were no significant differences between the PLA and no-PLA groups in age, sex, American Society of Anesthesiology performance status, cardiovascular comorbidity, or operation time. Chronic obstructive pulmonary disease (COPD) was the only preoperative variable predictive of PLA (P<0.05). Right upper lobectomy (RUL), either alone or in combination with right middle lobectomy, was associated with a significantly higher incidence of PLA than any other type of resection (P<0.05).

CONCLUSIONS

Postlobectomy atelectasis is an important postoperative complication. Patients with COPD and those undergoing RUL are at higher risk of this complication. Although often isolated, PLA is associated with longer hospital stay.

[Diagnostic flexible bronchoscopy. Recommendations of the Endoscopy Working Group of the French Society of Pulmonary Medicine]

These guidelines on flexible bronchoscopy depict important clues to be known and taken into account while practicing flexible bronchoscopy, in adult, except in emergency situations. This is a practical clarification. Safety conditions, complications, anesthesia, infectious risks, cleaning and disinfection are detailed from a review of the literature. Intensive care practice of bronchoscopy requires more attention due to higher risks patients and is discussed extensively. Standards and performances of the various sampling techniques complete this work. Indications for bronchoscopy, therapeutic and paediatric bronchoscopy are not covered in these guidelines.

Acupuncture for diagnostic fiberoptic bronchoscopy: a prospective, randomized, placebo-controlled study

Patients usually fear fiberoptic bronchoscopy (FBS) and they report a low level of satisfaction after this examination. We evaluated the efficacy of acupuncture in decreasing patient anxiety before diagnostic FBS and in improving tolerance to the examination. In a prospective double-blind study, we enrolled 48 patients scheduled to undergo diagnostic FBS. Patients were randomly assigned to one of three groups. Group A (16 patients): standard FBS, with airway topic anesthesia; Group B (16 patients): standard FBS, with airway topic anesthesia and acupuncture treatment; Group C (16 patients): standard FBS, with airway topic anesthesia and sham acupuncture. EKG, non-invasive arterial pressure, and pulse oximetry were monitored on a routine basis. We evaluated patient anxiety before and after acupuncture and, at the end of FBS, the discomfort suffered during the examination by a 100-mm Visual Analog Scale (VAS). Patient satisfaction in Group A was 50% worse than in Group B (p = 0.04). We observed a strong, even if not statistically significant, tendency toward a lower pre-FBS anxiety in Group B. Patients in group C had values very close to those recorded in group A. We observed no adverse event and no differences in cardio-respiratory parameters in these three groups; in particular, we did not observe a respiratory depression in Group B. Acupuncture seems an effective resource for a Thoracic Endoscopic Room to improve patient tolerance to FBS.

Contraindications and safety of transbronchial lung biopsy via flexible bronchoscopy. A survey of pulmonologists and review of the literature

BACKGROUND

Transbronchial lung biopsy (TBLB) via flexible bronchoscopy is a common procedure performed by pulmonologists. Limited scientific data exist concerning the risk of this procedure in patients with conditions that may adversely affect the rate of procedural complications.

OBJECTIVES

To evaluate the current practice pattern and attitude of pulmonologists toward the performance of TBLB in the presence of high-risk conditions.

METHODS

A survey was constructed and distributed at the American College of Chest Physicians annual meeting, held in Philadelphia, USA, in November of 2001.

RESULTS

A total of 227 surveys were distributed with a return of 158 (69.6%). Anticoagulation medications are temporarily held prior to TBLB by the majority of our survey respondents (98.7% for intravenous heparin, 90.5% for warfarin, and 87.3% for low-molecular-weight heparin). Medications with effect on platelet function are held by fewer pulmonologists. There is a wide variation in the pulmonologists' perception of the risk of performing TBLB when certain medical conditions coexist: pulmonary hypertension [absolute contraindication (AC), 28.7%; relative contraindication (RC) 58.6%], superior vena cava syndrome (AC 19.6%, RC 51%), mechanical ventilation (AC 17.8%, RC 58.6%) and lung cavity/abscess (AC 7%, RC 44.9%). A significant percentage of pulmonologists (55%) do not regard an elevated serum creatinine at any level as AC to TBLB. Thirty-eight percent of the survey participants administer desmopressin prior to TBLB in uremic patients to prevent excessive bleeding.

CONCLUSIONS

Prior to performing bronchoscopic TBLB, the majority of pulmonologists temporarily holds anticoagulation medications. However, there is a lack of agreement in relation to perceived contraindications and safety of TBLB.

Under-investigation of older people with abnormal chest radiographs

BACKGROUND

Whilst many authors have previously suggested that older people are under-represented in the investigation and management of lung cancer, few data are available as to the effect of age on the subsequent investigation and management of a patient with an abnormal chest radiograph.

METHODS

During a 3-month period in a university teaching hospital, all abnormal chest radiographs suggestive of a possible diagnosis of lung cancer were identified, and patients subsequently followed to determine investigation, management and date of death over a 5-year period.

RESULTS

Thirty-seven younger (</=69 years, median age 62 years) and 43 older patients (>/=70 years, median age 80 years) were identified. Of the 80 patients with a possible bronchial carcinoma only 59% had a further chest radiograph performed. Bronchoscopy was performed in 34% of patients, but a biopsy of the lesion was undertaken in only 24% of patients. Sixteen of the 80 patients, irrespective of what investigations had been undertaken, were referred for an oncological or surgical opinion. During the study period (3 months), 24% of the patients died. At 6, 24 and 60 months, respectively, the total deaths were 40, 78 and 88%.

CONCLUSION

Older patients compared with those aged less than 70 years were less likely to be investigated, further, were more likely to be managed differently (i.e., less aggressively) and more likely to die within each time interval. In more of the older group a presumed death certificate diagnosis of pneumonia was made. When an abnormal chest radiograph raises the possibility of an underlying bronchial carcinoma, the finding of this study suggests that an ageist attitude influences the subsequent management of some patients.

Bronchoscopy for atelectasis in the ICU: a case report and review of the literature

Fiberoptic bronchoscopy has become a commonplace procedure in ICUs. Despite the fact that one of the most common indications for bronchoscopy is the presence of retained secretions and atelectasis, there is little research dedicated to its safety and utility in this clinical situation. This article presents a case of an intubated trauma victim who had undergone numerous bronchoscopic procedures, with varying degrees of success, for retained secretions and atelectasis. This review then seeks to answer the following three main questions regarding bronchoscopy in critically ill patients: (1) Is bronchoscopy effective in resolving atelectasis? (2) Is bronchoscopy superior to other means of resolving atelectasis? (3) Is bronchoscopy safe in critically ill patients? The patient was a 28-year-old man with no significant medical history who presented to the emergency department after his car was hit by a dump truck. He was found to have multiple leg fractures and a splenic rupture, and he was taken to the operating room for an exploratory laparotomy, splenectomy, and reduction of his fractures. He was then brought to the surgical ICU intubated, sedated, and receiving mechanical ventilation. Over the next 6 h, he developed progressive hypoxemia and diffuse, bilateral alveolar infiltrates on a chest radiograph (CXR). Four days postoperatively, a routine CXR revealed total atelectasis of his right upper lobe (RUL). Emergent bronchoscopy was performed, and a large mucus plug obscuring the RUL bronchus was removed. Follow-up CXR demonstrated resolution of the atelectasis. The next day, RUL atelectasis was again seen on his CXR. A repeat bronchoscopic examination and BAL failed to reveal any plug. A follow-up CXR showed continued atelectasis. Over the next week, the patient underwent daily bronchoscopy for atelectasis with variable degrees of improvement. Over the next 3 weeks, his pulmonary status improved until he was eventually extubated, and 1 month after hospital admission he was discharged to rehabilitation.

Perioperative myocardial ischemia in patients undergoing sternectomy shortly after coronary artery bypass grafting

Coronary revascularization reduces cardiac complications associated with noncardiac surgery in patients with severe coronary disease. However, patients undergoing emergency noncardiac surgery soon after coronary bypass operations may still be vulnerable to ischemic myocardial events. We prospectively evaluated the incidence of myocardial ischemia in 82 consecutive patents scheduled for sternectomy in the first (Group 1; 35 patients) or second (Group 2; 47 patients) week after coronary artery bypass graft (CABG) surgery. The interval between CABG surgery and sternectomy in Groups 1 and 2 was 6 days (range, 4-7 days) and 11 days (range, 8-14 days), respectively. Electrocardiographic (ECG) changes consistent with myocardial ischemia were assessed with a two-channel Holter system for 48 h. There were no between-group differences in updated Acute Physiology and Chronic Health Evaluation score, use of beta-blockers, or perioperative hemodynamic changes. The incidence of ECG changes consistent with myocardial ischemia was fivefold more frequent in Group 1 (22.85% versus 4.25%; P < 0.05). Of the ischemic patients in Group 1, 25% experienced a perioperative acute myocardial infarction (one was fatal). There were no infarcts in Group 2. Thus, patients appear to be prone to coronary events during sternectomy performed early after CABG surgery. Although the incidence of ischemia did not differ from that previously reported after CABG surgery alone, further investigation is required to determine whether the findings obtained in this high-risk population are generalizable to patients undergoing noncardiac surgery soon after uneventful CABG surgery.

IMPLICATIONS

This study demonstrates an increased incidence of myocardial ischemia when sternectomy for mediastinitis is performed within one week of coronary artery bypass graft surgery, and this ischemia is associated with a 25% incidence of myocardial infarction.

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.

Role of bronchoscopy in modern medical intensive care unit

This article gives a broad overview of the increasingly important applications of bronchoscopy, flexible (FOB) and rigid (RB), in a modern medical intensive care unit. Special emphasis is made to bronchoscopy use in mechanically ventilated patients. Therapies such as endobronchial stenting and Nd:YAG laser are being used to improve respiratory failure and facilitate weaning from mechanical ventilation. Practical applications of recent advancements in technology (endobronchial stenting, laser therapy, and so forth), the increasing use of rigid bronchoscopy, and the new generation of flexible bronchoscopes like battery bronchoscopes, and ultra-thin bronchoscopes, are also discussed. The risks, potential benefits, complications, and suggested technique of performing bronchoscopy in mechanically ventilated patients are reviewed.

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.

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.

[Fiberoptic bronchoscopy during noninvasive positive-pressure ventilation in patients with chronic obstructive lung disease with hypoxemia and hypercapnia]

OBJECTIVES

To assess the feasibility and safety of non invasive positive-pressure ventilation (NIPPV) via a face mask to performing fiberoptic bronchoscopy (FOB) in patients with COPD contraindicating FOB in spontaneous ventilation.

STUDY DESIGN

Clinical, prospective, open, non comparative trial of feasibility.

PATIENTS

Ten consecutive COPD patients (71 +/- 5 year-old, PaO2 = 53 +/- 13 mmHg and PaCO2 = 67 +/- 11 mmHg), without any sign of acute respiratory failure, admitted to the intensive care unit for pneumonia requiring a bronchoalveolar lavage (BAL). Including were: PaO2 < 70 mmHg despite nasal O2 delivered at 3 L.min-1, PaCO2 > 50 mmHg, improvement of SpO2 with NIPPV before FOB.

METHODS

Topical anaesthesia of the nose and pharynx was obtained with a 5% lidocaine spray. NIPPV was administered using a ventilatory support system Evita 4 (Dräger) applied through a full facial mask secured to the patient with elastic straps. Patients were first allowed to acclimate for 5 min with NIPPV (IPAP = 16 cmH2O, EPAP = 0 and trigger of 0.3 cm H2O while a FIO2 kept at 0.7). A T-adapter Medisize (Péters) was attached to the facial mask. The tip of the FOB was inserted through the nose. Topical anaesthesia of the vocal cords was obtained with 1% lidocaine solution (3 mL). The FOB was inserted into the trachea up to a bronchial sub-segment. BAL was performed by instillation of 100 mL of saline solution. After FOB, the NIPPV was maintained for 5 min. Heart rate, SpO2 were measured continuously and arterial pressure at 2 min intervals. Arterial blood gas values were obtained just prior NIPPV and after 15 min and 60 min NIPPV disconnection.

RESULTS

FOB duration was 11 +/- 4 min. SpO2 significantly improved during FOB (from de 91 +/- 4.7% to 97% +/- 1.7) without decrease of oxygen saturation lower than 90%. There were no changes in PaCO2 and PaO2 during the hour following the end of procedure. FOB under NIPPV was performed in all patients without complications and was very well tolerated in eight patients. After NPPV disconnecting, one patient required again NIPPV for 15 min. No patient required endotracheal intubation within 24 hours. All patients survived.

CONCLUSION

Application of NIPPV during FOB is a safe technic for maintaining adequate gas exchange in hypoxaemic and hypercapnic COPD patients not in acute respiratory failure. After the end of the procedure a close surveillance in the intensive care unit is essential.

Effect of clonidine premedication on haemodynamic responses to fibreoptic bronchoscopy

The usual haemodynamic response to fibreoptic bronchoscopy is an increase in heart rate and blood pressure. We therefore compared, in a prospective, randomised, double-blind study, the effect of two doses of oral clonidine premedication (150 microg or 300 microg) with placebo (control group) on the haemodynamic alterations in 62 patients who underwent elective fibreoptic bronchoscopy. Significant increases in blood pressure and heart rate were observed during fibreoptic bronchoscopy only in the control group. Clonidine 150 microg blunted the haemodynamic response to fibreoptic bronchoscopy (p < 0.05). Significant decreases in systolic blood pressure (< 90 mmHg) were observed in all patients premedicated with 300 microg clonidine. Throughout the study nine patients (75%) in the 300 microg clonidine group were treated at least once for hypotension. Compared with the control group, time to awakening was significantly longer only in patients premedicated with 300 microg clonidine. In conclusion, premedication with 150 microg oral clonidine attenuates haemodynamic responses to fibreoptic bronchoscopy, without causing excessive haemodynamic depression and sedation. These data encourage the administration of clonidine as premedication in patients undergoing fibreoptic bronchoscopy, particularly in those with, or at risk for, coronary artery disease.

Coronary spasm during outpatient fiberoptic laser bronchoscopy

A 63-year-old woman with metastatic breast cancer was referred to our bronchoscopy unit for outpatient laser resection of an endobronchial mass through fiberoptic bronchoscopy. The patient had no history of ischemic heart disease. During the procedure, the patient developed an ST-segment elevation and a complete atrioventricular block. IV nitroglycerin and morphine were effective in treating this episode. In this patient, we were able to demonstrate a focal spasm by postbronchoscopy coronary angiography.

Patient satisfaction with conscious sedation for bronchoscopy

STUDY OBJECTIVE

Bronchoscopic technique is not standardized. Controversies exist with regard to premedication with sedatives before the test. To evaluate safety and efficacy of conscious sedation, we studied 100 randomized patients undergoing diagnostic bronchoscopy; patients received premedication with lidocaine spray and atropine sulfate i.m. (nonsedation group; 50 patients) or lidocaine spray, atropine i.m. and diazepam i.v. (sedation group; 50 patients).

METHODS AND RESULTS

Monitoring during flexible fiberoptic bronchoscopy included continuous ECG and pulse oximetry. The procedure could not be completed in six patients. None received premedication with diazepam; among the patients who ended the examination, tolerance to the examination (visual analogue scale, 0 to 100; 0 = excellent; 100 = unbearable) was better in the sedation group. Low anxiety, male sex, but not age were also associated with improved patient tolerance to the test. Oxygen desaturation occurred in 17% of patients, and it was not more frequent after diazepam treatment.

CONCLUSIONS

In our study, sedation had a beneficial effect on patient tolerance and rarely induced significant alterations in cardiorespiratory monitoring parameters.