Traditional conscious sedation for endobronchial ultrasound procedures places patients at risk of desaturation, and high-flow nasal oxygen may reduce the risk. We designed a parallel-group randomised controlled trial of high-flow nasal oxygen at a flow rate of 30-70 l.min via nasal cannulae, compared with standard oxygen therapy at 10 l.min via a bite block in adults planned for conscious sedation for endobronchial ultrasound. The primary outcome was the proportion of patients experiencing desaturation (defined as SpO < 90%). Secondary outcomes included oxygen saturation after pre-oxygenation, lowest oxygen saturation during procedure, number of hypoxic episodes, duration of hypoxia, end-procedure end-tidal CO , satisfaction scores and complications. Thirty participants were allocated to each group. Baseline patient characteristics, procedure time and anaesthetic agents used were similar between the groups. Desaturation occurred in 4 out of 30 patients allocated to the high-flow nasal oxygen group, compared with 10 out of 30 allocated to the standard oxygenation group, a non-significant difference (p = 0.07) with intention to treat analysis. The difference was significant (p = 0.047) when using a per-protocol analysis. Oxygen saturation after pre-oxygenation and the lowest oxygen saturation during procedure were significantly higher in the high-flow nasal oxygen group compared with the standard oxygenation group; median (IQR [range] 100 (99-100 [93-100]) vs. 98 (97-99 [94-100]), p = 0.0001 and 97.5 (94-99 [77-100]) vs. 92 (88-95 [79-98]), p < 0.001, respectively. There were no differences in other secondary outcomes. Although high-flow nasal oxygen may prevent desaturation due to some causes, it does not protect against hypoxaemia in all circumstances.

SummarySmoking is a risk factor for complications during and after surgery, but most smokers are unable to quit before elective surgery. We tested the efficacy of bupropion in improving smoking cessation rates in this setting by enrolling 47 patients from the elective surgery waiting list in a double-blind randomised controlled trial. Patients receiving bupropion had a lower daily cigarette consumption at the time of hospital admission, median (IQR) cigarettes per day: 6 (2-7) vs. 15 (9-20), p = 0.046. They also had a reduction in end-expired carbon monoxide (p = 0.004), a known contaminant of cigarette smoke, and increased arterial oxygen saturation on pulse oximetry (p = 0.011). They were more likely to have stopped smoking at the 3-week visit (p = 0.036), but not at the 6-week visit (p = 0.25) or at the time of hospital admission for surgery (p > 0.99). This study found that smokers waiting for elective surgery are more likely to reduce or stop smoking when treated with bupropion.

This study explored the use of high-flow nasal oxygen (HFNO) in both pre-oxygenation and apnoeic oxygenation in adults who were intubated following a non-rapid sequence induction. Fifty patients were randomised to receive pre-oxygenation via a standard facemask or the Transnasal Humidified Rapid-Insufflation Ventilatory Exchange (THRIVE) device. After five minutes of pre-oxygenation, induction and muscle relaxant agents were given. While waiting for complete paralysis, patients in the standard facemask group received bag-mask ventilation (BMV), whereas patients in the HFNO group received apnoeic oxygenation via the THRIVE device. Serial blood samples for arterial blood gas analysis were taken. Baseline patient and airway characteristics were similar. The median PaO 2 after pre-oxygenation was 357 (interquartile range [IQR] 324-450 [range 183-550]) mmHg in the facemask group, compared to 471 (IQR 429-516 [range 185-550]) mmHg in the HFNO group (P=0.01). The median arterial partial pressure of oxygen (PaO 2) in the HFNO group decreased after a period of apnoeic oxygenation, and was significantly lower when compared to patients who received BMV in facemask group. The arterial carbon dioxide partial pressure (PaCO 2) level after complete paralysis was significantly higher in the HFNO group when compared to the facemask group (median 52 [IQR 48-55 {range 40-65}] versus median 43 [IQR 40-48 {range 35-63}] mmHg, P=0.0005 and P=0.004 respectively). There were no differences in the time to muscle paralysis and time to intubation. Seven patients required use of airway adjuncts during BMV in the facemask group, compared to none in the HFNO group (P=0.004). No complications were observed in either group. HFNO produces a higher PaO 2 after pre-oxygenation and safe PaO 2 during intubation. However, the subsequent fall in PaO 2 and rise in PaCO 2 indicates that it is not as effective as BMV in maintaining oxygenation and ventilation following neuromuscular blockade.

The endoscopic dexterity required to proficiently drive a bronchoscope in human subjects to an anatomic endpoint relevant to fibreoptic intubation is achievable after 2-4 h of specialized bench training. Training in the local environment may be more conducive to success than in time-limited workshops. Achieving a defined proficiency standard on bench models contributes to the development of basic bronchoscopic competence. This has the potential to protect patients from novice learning curves, optimize clinical education and efficiency, and assist compliance with difficult airway algorithms.

Fibreoptic intubation remains an essential skill for anaesthetists to master. In addition to the reusable fibrescope, an alternative disposable videoscope is available (aScope™2, Ambu®, Ballerup, Denmark). A total of 60 anaesthetised adult patients were randomised to either having orotracheal intubation using the aScope 2 or a Karl Storz fibrescope. Intubations were performed by experienced operators who were familiar with both devices. The primary outcome was the Global Rating Scale score. Secondary outcomes included intubation success, number of intubation attempts and intubation time. Other subjective outcomes including practicality, useability and image quality were also recorded. There was no significant difference in the Global Rating Scale score, intubation success or intubation time between the aScope 2 or Karl Storz fibrescope. Global Rating Scale scores were three and two in the aScope 2 and Karl Storz groups respectively (P=0.14). All of the other subjective outcomes were similar between the two groups, except that operators found it easier to use the aScope 2 compared to the fibrescope. There was no significant difference in clinical performance between the aScope 2 and the Karl Storz fibreoptic bronchoscope. The aScope's practicality, disposability and recently improved version (aScope™3) potentially make it an acceptable alternative to the reusable fibrescope.