ObjectiveTo investigate the feasibility of electroencephalography (EEG) power spectrum analysis monitoring noninvasive intracranial pressure (ICP). MethodsBetween September 2008 and May 2009, the EEG signals were recorded in 62 patients (70 cases/times) with central nervous system (CNS). By using self-designed software, EEG power spectrum analysis was conducted and pressure index (PI) was calculated automatically. ICP was measured by lumbar puncture (LP). ResultsThe mean ICP was (239.74±116.25) mm H2O (70-500 mm H2O, 1 mm H2O=0.009 8 kPa), and 52.9% of patients had increased ICP. The mean PI was 0.29±0.20 (0.02-0.85). The Spearman rank test showed that there was a significant negative correlation between PI and ICP (rs=-0.849, P<0.01). The data from the patients with diffuse lesions of CNS and focal lesions were analyzed separately; the results showed there were significant negative correlations between PI and ICP in both groups (rs=-0.815, -0.912; P<0.01). ConclusionThe PI obtained from EEG analysis is correlated with ICP. Analysis of specific parameters from EEG power spectrum might reflect the ICP. Further research should be carried out.
Objective To investigate the safety of high fraction of inspired oxygen (FiO2)during noninvasive ventilation in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD)and carbon dioxide (CO2)retention. Methods Fifty-six AECOPD patients with CO2 retention admitted between March 2013 and August 2015 were recruited in the study.All patients received noninvasive ventilation treatment with FiO2<0.5.After stabilization of acute respiratory crisis,FiO2 was increased to 1.0 and lasted for 40 minutes.The changes of tidal volume,respiratory frequency,minute volume,Glasgow coma score,arterial blood gas and SpO2 were observed before and after the FiO2 reset. Results The mean PaO2 increased from (83±14)mm Hg to (165±41)mm Hg and the mean SpO2 increased from (92.4±3.1)% to (97.8±1.9)% significantly (both P<0.001).The mean PaCO2 did not changed obviously from (72±15)mm Hg to (72±14)mm Hg (P=0.438).There were also no significant changes in any of the other parameters. Conclusion During noninvasive ventilation with an FiO2 sufficient to maintain a normal PaO2,an increase in FiO2 does not further increase PaCO2 level in AECOPD patients with CO2 retention.