Introduction
Endobronchial ultrasound-guided transbronchial needle
aspiration (EBUS-TBNA) is a minimally invasive diagnostic method for
mediastinal/hilar lymphadenopathies and masses [1]. During the
EBUS-TBNA, all relevant lymph node stations should be evaluated and
optimal results can be obtained by three aspirations per lymph node
station [2]. The procedure induces cough, increases airway
secretions, and reduces airway caliber. Because of these reasons, the
procedure should be performed with sedation that provides both patient’s
comfort and bronchoscopist’s ability for obtaining adequate tissue.
Intravenous sedation (a combination of alfentanyl/fentanyl, propofol,
and/or midazolam) is commonly used in EBUS-TBNA procedure. However
desaturation is the major problem during sedation because sedation
causes upper airway obstruction, respiratory depression and
hypoventilation due to muscle relaxation [3,4]. Hypoxemia can lead
to sympathetic activation and may cause tachycardia and hypertension.
During bronchoscopic procedures, patients stay under spontaneous
breathing and Oxygen is delivered through a mask. Arterial Oxygen
saturation should be at least 90% to reduce the risk of significant
arrhythmia [5]. Drugs for anesthesia or sedation can increase the
severity of obstructive sleep apnea. Propofol is known to contribute to
the narrowing of the upper airway by decreasing the activity of
genioglossus muscle in proportion to its concentration. [6].
Continuous positive airway pressure (CPAP) has a mechanical effect that
increases the intraluminal pressure of the upper airway above the
positive transmural pressure of the pharynx and hypopharynx. CPAP has
been shown to improve the decreased tidal volume and airflow during
sedation for bronchoscopy in children [7]. Additionally,
jaw-thrust and CPAP application have been shown to improve ventilation
in infants under anesthesia [8]. To our knowledge, there is no study
on the effect of nCPAP on Oxygen desaturation during the EBUS-TBNA. In
this study, our aim was to investigate the effect of Oxygen application
with nCPAP on hypoxemia during EBUS-TBNA.