The protective mechanism of hypoxic pulmonary vasoconstriction during one-lung ventilation (OLV) is impaired in patients with a low diffusing capacity for carbon monoxide (DLCO). We hypothesized that iloprost inhalation would improve oxygenation and lung mechanics in patients with low DLCO who underwent pulmonary resection. Forty patients with a DLCO < 75% were enrolled. Patients were allocated into either an iloprost group (ILO group) or a control group (n = 20 each), in which iloprost and saline were inhaled, respectively. The partial pressure of arterial oxygen/fraction of inspired oxygen (PaO2/FiO2) ratio, pulmonary shunt fraction, alveolar dead space, dynamic compliance, and hemodynamic parameters were assessed 20 min after the initiation of OLV and 20 min after drug administration. Repeated variables were analyzed using a linear mixed model between the groups. Data from 39 patients were analyzed. After iloprost inhalation, the ILO group exhibited a significant increase in the PaO2/FiO2 ratio and a decrease in alveolar dead space compared with the control group (p = 0.025 and p = 0.042, respectively). Pulmonary shunt, dynamic compliance, hemodynamic parameters, and short-term prognosis were comparable between the two groups. Selective iloprost administration during OLV reduced alveolar dead space and improved oxygenation while minimally affecting hemodynamics and short-term prognosis.

Background Radial artery cannulation can cause complications such as haematoma formation or thrombosis due to its small diameter. Recently, a novel ultrasound device equipped with an electromagnetic guidance system was introduced, showing the path and alignment of the needle during the procedure. The aim of this study was to investigate the effects of this novel system on both success and complication rates during radial artery cannulation under ultrasound guidance. Methods In this randomized controlled trial, 76 adults scheduled for neurosurgery requiring radial artery cannulation were recruited. In group E (n = 38), radial artery cannulation was performed using the electromagnetic guidance ultrasound system, whereas in group C (n = 38), the procedure was performed using conventional ultrasound guidance. The success rates of cannulation on the first attempt, cannulation times, number of attempts, and incidence of complications were compared between the two groups. Results There was a significant difference in the success rates on the first attempt between the two groups (group C = 78.9% vs. group E = 94.7%, P = 0.042). Incidences of posterior wall puncture and haematoma formation (group C = 8 vs. group E = 1; P = 0.028) were significantly lower in group E than in group C. The median cannulation time for successful attempts was comparable between groups. Conclusions Use of the novel electromagnetic guidance system resulted in a better success rate on the first attempt and a lower incidence of complications during radial artery cannulation. Trial registration This study was registered at http://cris.nih.go.kr (registration number: KCT0002476).

This study sought to determine whether intraoperative dexmedetomidine infusion might reduce the incidence of postoperative cognitive dysfunction (POCD) and alleviate the neuroinflammatory response in patients who have undergone arthroscopic shoulder surgery. A total of 80 patients over 60 years of age who had undergone arthroscopic shoulder surgery in the beach chair position were randomly allocated to either the dexmedetomidine group (Group D) or the control group (Group C). Dexmedetomidine (0.6 μg/kg/h) or a comparable amount of normal saline was infused into each group during the surgery. The early incidence of POCD was assessed by comparing cognitive tests on the day before and 1 d after surgery. The neuroinflammatory response with the S100 calcium-binding protein B (S100β) assay was compared prior to anesthetic induction and 1 h following surgery. The incidence of POCD was comparable between groups D (n = 9, 22.5%) and C (n = 9, 23.7%) (p = 0.901). However, the results of the cognitive test revealed a significant difference between the groups after surgery (p = 0.004). Although the S100β levels measured at the end of surgery were significantly higher than those at baseline in both groups (p < 0.001), there was no difference between the groups after the surgery (p = 0.236). Our results suggest that intraoperative dexmedetomidine infusion neither reduce the incidence of early POCD nor alleviated the neuroinflammatory response in patients undergoing arthroscopic shoulder surgery.

Anesthesiologists are exposed to the risk of infection from various secretions or droplets from the respiratory tract of patients. We aimed to determine bacterial exposure to anesthesiologists' faces during endotracheal intubation and extubation. Methods: Six resident anesthesiologists performed 66 intubation and 66 extubation procedures in patients undergoing elective otorhinolaryngology surgeries. Sampling was performed by swabbing the face shields twice in an overlapping slalom pattern, before and after each procedure. Samples for pre-intubation and pre-extubation were collected immediately after wearing the face shield at the time of anesthesia induction and at the end of the surgery, respectively. Post-intubation samples were collected after the injection of anesthetic drugs, positive pressure mask ventilation, endotracheal intubation, and confirmation of intubation success. Post-extubation samples were collected after endotracheal tube suction, oral suction, extubation, and confirmation of spontaneous breathing and stable vital signs. All swabs were cultured for 48 h, and bacterial growth was confirmed by colony forming unit (CFU) count. Results: There was no bacterial growth in either pre-or post-intubation bacterial cultures. In contrast, while there was no bacterial growth in pre-extubation samples, 15.2% of post-extubation samples were CFU+ (0/66 [0%] vs 10/66 [15.2%], p=0.001). All the CFU+ samples belonged to 47 patients with post-extubation coughing, and the CFU count was correlated with the number of coughing episodes during the process of extubation (P < 0.01, correlation coefficient= 0.403). Conclusion:The current study shows the actual chance of bacterial exposure to the anesthesiologist's face during the patient awakening process after general anesthesia. Given the correlation between the CFU count and the number of coughing episodes, we recommend anesthesiologists to use appropriate facial protection equipment during this procedure.

Purpose After inflating the cuff of the endotracheal tube, the pressure of the cuff should be evaluated as to whether it is appropriate for ventilation. The most commonly used method is pilot balloon palpation. This study evaluated whether the size of the tracheal tube influenced the accuracy of pilot balloon palpation. Methods A prospective observational analysis of 208 patients intubated with an endotracheal tube of internal diameter (ID) 6.0 or 8.0 was conducted. An anesthesiologist first judged whether the cuff pressure was appropriate by manual pilot balloon palpation, and then measured the cuff pressure with a pressure gauge. If the cuff pressure exceeded 20–30 cmH2O, it was defined as a false recognition. Results The intracuff pressure was significantly higher in ID 6.0 tube than in the ID 8.0 tube (41.9 ± 18.8 cmH2O vs. 30.3 ± 11.9 cmH2O, p < 0.001). The number of patients that were mistakenly perceived to have appropriate cuff pressure by pilot balloon palpation was significantly higher in the ID 6.0 group compared to the ID 8.0 group (85 (81.7%) vs. 64 (61.5%), p = 0.001). Conclusions The incidence of inaccurate assessment of adequate cuff pressure when determining cuff pressure by pilot balloon palpation was higher in the relatively smaller endotracheal tube size group compared to the larger endotracheal tube size group. Therefore, use of a pressure gauge to confirm adequate pressure is recommended especially when using a smaller tube size.

Oxygen supplementation is crucial for awake tracheal intubation (ATI) using a flexible bronchoscope in patients with an anticipated difficult airway. However, the modality of optimal oxygen delivery remains unclear. This retrospective study compared high-flow nasal oxygen (HFNO) and conventional low-flow oxygen supply during ATI. We applied inverse probability of treatment weighting (IPTW) to account for biases due to clinical characteristic differences between the groups. The primary endpoint was the lowest oxygen saturation during ATI. The secondary endpoints were incidence of desaturation, multiple attempts, failure rate, and procedural duration. After IPTW adjustment, the lowest oxygen saturation in the HFNO group during ATI was significantly higher than that in the conventional oxygenation group (99.3 ± 0.2 vs. 97.5 ± 0.5, P < 0.001). Moreover, the HFNO group had fewer cases with multiple attempts than the conventional oxygenation group (3% vs. 16%, P = 0.007). There were no significant differences between the two groups in the incidence of desaturation, failure and procedural duration. Our findings suggest that HFNO was associated with improved lowest oxygen saturation and a lower rate of multiple attempts during ATI. Therefore, we recommend using HFNO for safer oxygen delivery and improved quality of procedure during ATI.