Effect of permissive hypercarbia on lung oxygenation during one-lung ventilation and postoperative pulmonary complications in patients undergoing thoracic surgery: A prospective randomised controlled trial.

BACKGROUND: The effect of hypercarbia on lung oxygenation during thoracic surgery remains unclear. OBJECTIVE: To investigate the effect of hypercarbia on lung oxygenation during one-lung ventilation in patients undergoing thoracic surgery and evaluate the incidence of postoperative pulmonary complications. DESIGN: Prospective randomised controlled trial. SETTING: A tertiary university hospital in the Republic of Korea from November 2019 to December 2020. PATIENTS: Two hundred and ninety-seven patients with American Society of Anaesthesiologists physical status II to III, scheduled to undergo elective lung resection surgery. INTERVENTION: Patients were randomly assigned to Group 40, 50, or 60. An autoflow ventilation mode with a lung protective ventilation strategy was applied to all patients. Respiratory rate was adjusted to maintain a partial pressure of arterial carbon dioxide of 40 ±â€Š5 mmHg in Group 40, 50 ±â€Š5 mmHg in Group 50 and 60 ±â€Š5 mmHg in Group 60 during one-lung ventilation and at the end of surgery. MAIN OUTCOME MEASURES: The primary outcome was the arterial oxygen partial pressure/fractional inspired oxygen ratio after 60 min of one-lung ventilation. RESULTS: Data from 262 patients were analysed. The partial pressure/fractional inspired oxygen ratio was significantly higher in Group 50 and Group 60 than in Group 40 (269.4 vs. 262.9 vs. 214.4; P  < 0.001) but was not significantly different between Group 50 and Group 60. The incidence of postoperative pulmonary complications was comparable among the three groups. CONCLUSION: Permissive hypercarbia improved lung oxygenation during one-lung ventilation without increasing the risk of postoperative pulmonary complications or the length of hospital stay. TRIAL REGISTRATION: NCT04175379.

Effects of dexmedetomidine on oxygenation and lung mechanics in patients with moderate chronic obstructive pulmonary disease undergoing lung cancer surgery: A randomised double-blinded trial.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a risk factor that increases the incidence of postoperative cardiopulmonary morbidity and mortality after lung resection. Dexmedetomidine, a selective α2-adrenoreceptor agonist, has been reported previously to attenuate intrapulmonary shunt during one-lung ventilation (OLV) and to alleviate bronchoconstriction. OBJECTIVE: The objective is to determine whether dexmedetomidine improves oxygenation and lung mechanics in patients with moderate COPD during lung cancer surgery. DESIGN: A randomised, double-blinded, placebo-controlled study. SETTING: Single university hospital. PARTICIPANTS: Fifty patients scheduled for video-assisted thoracoscopic surgery who had moderate COPD. Patients were randomly allocated to a control group or a Dex group (n = 25 each). INTERVENTIONS: In the Dex group, dexmedetomidine was given as an initial loading dose of 1.0  µg  kg(-1) over 10  min followed by a maintenance dose of 0.5  µg  kg(-1)  h(-1) during OLV while the control group was administered a comparable volume of 0.9% saline. Data were measured at 30  min (DEX-30) and 60  min (DEX-60) after dexmedetomidine or saline administration during OLV. MAIN OUTCOME MEASURES: The primary outcome was the effect of dexmedetomidine on oxygenation. The secondary outcome was the effect of dexmedetomidine administration on postoperative pulmonary complications. RESULTS: Patients in the Dex group had a significantly higher PaO2/FIO2 ratio (27.9 ±â€Š5.8 vs. 22.5 ±â€Š8.4 and 28.6 ±â€Š5.9 vs. 21.0 ±â€Š9.9 kPa, P < 0.05), significantly lower dead space ventilation (19.2 ±â€Š8.5 vs. 24.1 ±â€Š8.1 and 19.6 ±â€Š6.7 vs. 25.3 ±â€Š7.8%, P < 0.05) and higher dynamic compliance at DEX-30 and DEX-60 (P = 0.0001 and P = 0.0184) compared with the control group. In the Dex group, the PaO2/FIO2 ratio in the postoperative period was significantly higher (P = 0.022) and the incidence of ICU admission was lower than in the control group. CONCLUSION: Dexmedetomidine administration may provide clinically relevant benefits by improving oxygenation and lung mechanics in patients with moderate COPD undergoing lung cancer surgery. TRIAL REGISTRATION: ClinicalTrial.gov identifier: NCT 02185430.

Use of silane-functionalized graphene oxide in organic photovoltaic cells and organic light-emitting diodes.

Graphene oxide (GO) and silane-functionalized GO (sGO) sheets obtained through a simple sonication exfoliation method are employed as hole transport layers to improve the efficiency of organic photovoltaic (OPV) cells and organic light-emitting diodes (OLED). GO was functionalized using (3-glycidyl oxypropyl)trimethoxysilane (GPTMS) and triethoxymethylsilane (MTES). The appearance of new peaks in the Fourier-transform infrared spectra of the sGOs indicates the formation of Si-O-C, Si-O-Si, Si-H, and Si-O-C moieties, which provide evidence of the addition of silane to the GO surface. Furthermore, the appearance of Si-O-Si bonds in the synchrotron radiation photoelectron spectra (SRPES) of the MTES-sGO and GPTMS-sGO samples suggests that silane groups were effectively functionalized onto the GO sheets. An OPV cell with GO layers showed a lower performance with a power conversion efficiency (PCE) of 2.06%; in contrast, OPV cells based on GPTMS-sGO and MTES-sGO have PCE values of 3.00 and 3.08%, respectively. The OLED devices based on GPTMS-sGO and MTES-sGO showed a higher maximum luminance efficiency of 13.91 and 12.77 cd A(-1), respectively, than PEDOT:PSS-based devices (12.34 cd A(-1)). The SRPES results revealed that the work functions of GO, GPTMS-sGO, and MTES-sGO were 4.8, 4.9, and 5.0 eV, respectively. Therefore, the increase in the PCE value is attributed to improved band-gap alignment. It is thought that sGO could be used as an interfacial layer in OPV and OLED devices.

Intraoperative Dexmedetomidine Improves the Quality of Recovery and Postoperative Pulmonary Function in Patients Undergoing Video-assisted Thoracoscopic Surgery: A CONSORT-Prospective, Randomized, Controlled Trial.

Video-assisted thoracoscopic surgery (VATS) has been known to be a stressful event for patients, and dexmedetomidine is known to attenuate surgery-induced sympathetic responses and potentiate analgesia in perioperative periods. The present was designed to evaluate the effects of intraoperative dexmedetomidine administration on the quality of recovery (QoR) and pulmonary function after VATS. Patients with lung cancer undergoing VATS were randomized to Dex group (loading of 1.0 µg/kg for 20 minutes before the termination of surgery, n = 50) or Control group (comparable volume of normal saline, n = 50). The QoR-40 questionnaire assesses postoperative recovery and validates the overall surgical and general anesthesia outcomes. The QoR-40 scores, forced expiratory volume for 1 second (FEV1) on postoperative day (POD) 1 and 2, and emergence agitation were evaluated. The global QoR-40 score (162.3 ±â€Š17.8 vs 153.3 ±â€Š18.7, P = 0.016 on POD 1; 174.3 ±â€Š16.0 vs 166.8 ±â€Š16.7, P = 0.028 on POD 2) and FEV1 (2.1 ±â€Š0.4 vs 1.9 ±â€Š0.5 L, P = 0.034 on POD 1; 2.2 ±â€Š0.5 vs 2.0 ±â€Š0.4 L, P = 0.030 on POD 2) were significantly higher in the Dex group compared with the Control group on POD1 and POD 2. The score of emergence agitation was lower in the Dex group compared with the Control group (3 [2-5] vs 5 [3-7], P < 0.001). The number of patients indicating severe emergence agitation was shorter in the Dex group than Control group (0 [0%] vs 7 [14%], P = 0.048). The length of hospital stay was significantly shorter (6.7 [3-9] vs 8.4 [4-9] days, P = 0.045) in the Dex group compared with the Control group. Intraoperative dexmedetomidine administration improved QoR, postoperative pulmonary function, and emergence agitation in patients undergoing VATS. Consequently, intraoperative dexmedetomidine administration could improve postoperative outcomes and reduced the length of hospital stay in patients undergoing VATS.

Effects of intraoperative inhaled iloprost on primary graft dysfunction after lung transplantation: A retrospective single center study.

DESIGN: Inhaled iloprost was known to alleviate ischemic-reperfusion lung injury. We investigated whether intraoperative inhaled iloprost can prevent the development of primary graft dysfunction after lung transplantation. Data for a consecutive series of patients who underwent lung transplantation with extracorporeal membrane oxygenation were retrieved. By propensity score matching, 2 comparable groups of 30 patients were obtained: patients who inhaled iloprost immediately after reperfusion of the grafted lung (ILO group); patients who did not receive iloprost (non-ILO group). RESULTS: The severity of pulmonary infiltration on postoperative days (PODs) 1 to 3 was significantly lower in the ILO group compared to the non-ILO group. The PaO2/FiO2 ratio was significantly higher in the ILO group compared to the non-ILO group (318.2 ± 74.2 vs 275.9 ± 65.3 mm Hg, P = 0.022 on POD 1; 351.4 ± 58.2 vs 295.8 ± 53.7 mm Hg, P = 0.017 on POD 2; and 378.8 ± 51.9 vs 320.2 ± 66.2 mm Hg, P = 0.013 on POD 3, respectively). The prevalence of the primary graft dysfunction grade 3 was lower in the ILO group compared to the non-ILO group (P = 0.042 on POD 1; P = 0.026 on POD 2; P = 0.024 on POD 3, respectively). The duration of ventilator use and intensive care unit were significantly reduced in the ILO group (P = 0.041 and 0.038). CONCLUSIONS: Intraoperative inhaled iloprost could prevent primary graft dysfunction and preserve allograft function, thus reducing the length of ventilator care and intensive care unit stay, and improving the overall early post-transplant morbidity in patients undergoing lung transplantation.