Objective:To evaluate the effect of hydrogen on lung injury induced by extremity ischemia-reperfusion (I/R) in elderly patients.Methods:Sixty American Society of Anesthesiologists physical status Ⅱ or Ⅲ elderly patients, aged 65-75 yr, with height 155-180 cm, weighing 50-75 kg, undergoing lower limb surgery under spinal anesthesia, were divided into 2 groups ( n=30 each) using a random number table method: hydrogen inhalation group (H group) and control group (C group). In H group, 67% hydrogen-33% oxygen was inhaled through the nasal catheter until the end of surgery starting from the completion of anesthesia.In group C, 33% oxygen was inhaled through the nasal catheter until the end of surgery after the completion of anesthesia.Blood samples from the radial artery were collected before anesthesia and at 60 min after tourniquet deflation.Blood gas analysis was performed to determine and record arterial oxygen partial pressure (PaO 2) and arterial carbon dioxide partial pressure (PaCO 2), and alveolar-arterial partial pressure of oxygen difference (A-aDO 2), oxygenation index (OI) and respiratory index (RI) were calculated.Pulmonary surfactant protein D (SP-D) and interleukin-6 (IL-6) concentrations in serum were measured by enzyme-linked immuno sorbent assay.ICU stay time and incidence of pulmonary complications within 7 days after operation were recorded. Results:Compared with group C, PaO 2 and OI were significantly increased, RI and A-aDO 2 were decreased, SP-D and IL-6 concentrations in serum were decreased at 60 min after tourniquet deflation, and ICU stay time was shortened ( P<0.05), and no significant change was found in the incidence of pulmonary complications within 7 days after surgery in group H ( P>0.05). Conclusion:Hydrogen can reduce the lung injury induced by extremity I/R, and the mechanism may be related to the reduction of inflammatory response in elderly patients.

Objective:To evaluate the effect of hydrogen on the occurrence of pulmonary complications after thoracoscopic radical resection of lung cancer.Methods:One hundred and ten patients of both sexes, aged 45-75 yr, with body mass index of 18-23 kg/m 2, of American Society of Anesthesiologists physical status Ⅰ-Ⅲ, scheduled for elective thoracoscopic radical resection of lung cancer, were divided into 2 groups ( n=55 each) using the random number table method: hydrogen group (group H) and control group (group C). Patients inhaled 66.7% hydrogen for 60 min before anesthesia in group H, while 33% oxygen was inhaled for 60 min in group C. Blood samples were collected from the radial artery at 5 min before one-lung ventilation (T 0) and 1 h of one-lung ventilation (T 1) for blood gas analysis and for determination of peak airway pressure, airway plateau pressure, driving pressure and dynamic lung compliance.Oxygenation index was calculated.Bronchoalveolar lavage fluid on the ventilated side was collected at T 0 and T 1 for measurment of interleukin-6 concentrations by enzyme-linked immunosorbent assay.The incidence of pulmonary complications within 7 days after surgery was recorded. Results:Compared with group C, the oxygenation index and dynamic lung compliance were significantly increased, and the peak airway pressure, airway plateau pressure, driving pressure, interleukin-6 concentrations in bronchoalveolar lavage fluid, and incidence of pulmonary complications within 7 days after surgery were decreased in group H ( P<0.05). Conclusion:Hydrogen can decrease the occurrence of pulmonary complications, and the mechanism is related to reducing lung inflammatory responses and improving lung compliance in the patients undergoing thoracoscopic radical resection of lung cancer.