Propofol post-conditioning after temporary clipping reverses oxidative stress in aneurysm surgery.

PURPOSE: Animal studies have demonstrated that propofol post-conditioning produces long-term neuroprotection in focal cerebral ischemia-reperfusion injury. However, whether propofol post-conditioning provides neuroprotection in human beings has never been explored. The aim of this study was to evaluate the role of propofol post-conditioning on oxidative stress and post-operative cognitive function following aneurysm clipping. MATERIALS AND METHODS: Sixty patients undergoing intracranial aneurysm clipping were randomized into a propofol post-conditioning group or a sevoflurane group. Sevoflurane (0.5-2%) was used for maintenance anesthesia in both groups. In the propofol post-conditioning group, the inhaled concentration of sevoflurane was reduced after temporary clip removal to keep the bispectral index (BIS) value between 40 and 60, and propofol (Cp 1.2 µg/mL) was subsequently started. Blood samples were drawn at six time points: before induction, immediately after clip removal, at the end of the operation, 24-h post-surgery, 3 days post-surgery, and 7 days post-surgery. Oxidative stress and cognitive function were measured. RESULTS: Between the conclusion of the operation to 7 days after surgery, propofol post-conditioning decreased the serum concentration of •OH and 8-isoprostane and increased γ-tocopherol and SOD. Reduced micronuclei and nucleoplasmic bridges were observed in the propofol post-conditioning group. Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) scores were improved by propofol post-conditioning compared to the group that received no propofol. CONCLUSIONS: Together, our data suggest that propofol post-conditioning (Cp 1.2 µg/mL) may protect the brain from oxidative stress injury up to 7 days post-surgery after temporary parent artery clipping. Furthermore, the neuroprotection induced by propofol post-conditioning may contribute to improvement in cognitive function.

Comparisons of clinical performance of Guardian laryngeal mask with laryngeal mask airway ProSeal.

BACKGROUND: The Guardian Laryngeal Mask Airway (G-LMA) is a new silicone-based single-use extraglottic device with the drainage port and a cuff pilot valve with pressure indicator. The aim of this study is to compare the clinical performance of this laryngeal mask airway with ProSeal laryngeal mask airway (P-LMA). METHODS: In this prospective randomized study, we included adult patients with ASA grading I and II scheduled for elective surgery requiring supine position under total intravenous anesthesia. The patients were randomly allocated to two groups, 40 in each. G-LMA and P-LMA were used in groups G and P respectively. The cuff of each device was air inflated to 60 cmH2O. The primary outcome was to compare the airway sealing pressure and the secondary outcome was to compare the efficacy and safety of these two devices with respect to insertion success, insertion time, ease of insertion, volume of air for cuff inflation to 60 cmH2O, intracuff pressure measurement, gastric tube insertion attempt, gastric tube insertion time, Fiberoptic laryngeal view, and postoperative pharyngolaryngeal morbidity. RESULTS: The airway sealing pressure at 60 cmH2O cuff pressure was significantly greater in G-LMA than P-LMA (p = 0.04).The first successful attempt of both groups were comparable (p = 1.000). Insertion time was significantly shorter in G-LMA than P-LMA (p < 0.0001). The first successful attempt for the gastric tube insertion in both groups was comparable (p = 0.431). Gastric tube insertion time was less in G-LMA than in P-LMA (p < 0.0001). The volume of air for cuff inflation to 60 cmH2O was more in G-LMA than in P-LMA (<0.0001). The intracuff pressure measurement at 30, 60, 90 and 120 minutes were comparable (p = 0.823, 0.182, 0.870, 0.658).We did not find differences in ease of insertion (p = 0.60); Fiber-optic positions of airway devices were comparable (p = 0.83). In addition, blood staining (p = 1.00), sore throat and dysphagia at 1, 2 and 24 hour (p = 1.00) were comparable in both groups. CONCLUSION: The Guardian laryngeal mask airway was associated with high airway sealing pressure with a quicker insertion of the device as well as gastric tube. TRIAL REGISTRATION: Clinical Trial.gov Identifier: NCT02063516. Date: June 2013.