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

Abstract

<b><i>Background:</i></b> 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. <b><i>Objectives:</i></b> We investigated the impact of COPD on hypercapnia during FB with endobronchial ultrasound (EBUS) in sedation and how the periprocedural monitoring should be adapted. <b><i>Methods:</i></b> 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 (p<sub>tc</sub>CO<sub>2</sub>) before, during, and for 60 min after the sedation with midazolam and alfentanil. <b><i>Main Results:</i></b> 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 p<sub>tc</sub>CO<sub>2</sub> (53.7 ± 7.1 vs. 46.8 ± 4.8 mm Hg, <i>p</i> < 0.001) and mean p<sub>tc</sub>CO<sub>2</sub> (49.5 ± 6.8 vs. 44.0 ± 4.4 mm Hg, <i>p</i> < 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, <i>p</i> < 0.001). They needed a nasopharyngeal tube more often (28 vs. 11%, <i>p</i> < 0.001). All patients recovered from hypercapnia within 60 min after FB. No intermittent ventilation manoeuvres were needed. <b><i>Conclusion:</i></b> A relevant proportion of patients reached their peak-pCO<sub>2</sub> 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.

Contribution of budesonide nebulization in bronchoscopy

“…The time in observation group was signi cantly shorter than that in the control group (18 ± 3 min versus 20 ± 3 min, P < 0.01), and the time of additional lidocaine [3 (2, 3) versus 3 (3,4), P < 0.001] and the dosage of lidocaine [4.57 (4.00, 5.00) versus 4.80 (4.28, 5.52), P < 0.05] were signi cantly less than those in control group.…”

“…In recent years, the implementation of bronchoscopy under general anesthesia has signi cantly improved the experience of patients, allowing complex and time-consuming procedures such as interventional therapy to be achieved. Bronchoscopy under conscious sedation has also been recommended by several studies and guidelines [1][2][3][4] . However, the economic/technological development and the allocation of medical resources in different countries (even in different regions of the same country) have been revealed to be extremely imbalanced, accompanied with a tough comprehensive promotion of general anesthesia and painless bronchoscopy, causing topical anesthesia for preexamination preparation still be applied by amounts of hospital.…”

Prevention of droplet dispersal with ‘e‐mask’: A new daily use endoscopic mask during bronchoscopy

“…We compared the e‐mask group with consecutive patients who underwent bronchoscopy without the e‐mask (control group) between 1 April 2011 and 30 September 2011 since the record of EtCO 2 during bronchoscopy was only during this period of time in 2011. Further details are provided in Appendix S1 and Figure S1 in the Supporting Information 15–20 …”

“…Further details are provided in Appendix S1 and Figure S1 in the Supporting Information. [15][16][17][18][19][20]…”