Multiple comorbid sleep disorders adversely affect quality of life in Parkinson's disease patients.

Sleep disorders are common non-motor symptoms in patients with Parkinson's disease (PD). The characteristics and impact of multiple comorbid sleep disorders remain to be elucidated. Our goal was to investigate the characteristics of various sleep disorder comorbidities, and their association with motor complications and the impact on the quality of life in PD patients. In this multicenter, observational, cross-sectional study, data concerning the clinical characteristics of complicated sleep disorders were collected from PD patients treated at 40 different hospitals in Shanghai. Sleep disorders were evaluated using the PD Sleep Scale-2, Epworth Sleepiness Scale, Rapid Eye Movement Sleep Behavior Disorder Questionnaire-Hong Kong, and the International Restless Legs Scale. Among the 1006 subjects evaluated, 77.53% exhibited signs of sleep disorders, and most had multiple sleep disorders (n = 502, 49.9%). A smaller percentage of patients with sleep disorders had a single disorder (n = 278, 27.6%). Furthermore, an increased number of sleep disorders, including nighttime problems, excessive daytime sleepiness, rapid eye movement sleep behavior disorder, and restless legs syndrome was a significant contributor to a poor quality of life (ß = 4.33, CI: 3.33-5.33, P for trend <0.001), even when controlling for multiple factors. Moreover, motor complications partially mediated this relationship (indirect effect: ß = 0.355, 95% boot CI: 0.134, 0.652).Our study showed that a large proportion of PD patients suffer from multiple comorbid sleep disorders, which greatly decreases the quality of life in PD patients and is partially mediated by motor complications.

Neurological manifestations of COVID-19: a systematic review.

INTRODUCTION: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for the global spread of coronavirus disease (COVID-19). Our understanding of the impact this virus has on the nervous system is limited. Our review aims to inform and improve decision-making among the physicians treating COVID-19 by presenting a systematic analysis of the neurological manifestations experienced within these patients. METHODS: Any study, released prior to May 20, 2020, that reported neurological manifestations in patients infected by SARS-CoV-2 was systematically reviewed using the PRISMA (Preferred Reporting Items for Systemic review and Meta-Analysis) statement. RESULTS: Our systematic review included data from 37 articles: twelve retrospective studies, two prospective studies, and the rest case reports/series. The most commonly reported neurological manifestations of COVID-19 were myalgia, headache, altered sensorium, hyposmia, and hypogeusia. Uncommonly, COVID-19 can also present with central nervous system manifestations such as ischemic stroke, intracerebral hemorrhage, encephalo-myelitis, and acute myelitis, peripheral nervous manifestations such as Guillain-Barré syndrome and Bell's palsy, and skeletal muscle manifestations such as rhabdomyolysis. CONCLUSION: While COVID-19 typically presents as a self-limiting respiratory disease, it has been reported in up to 20% of patients to progress to severe illness with multi-organ involvement. The neurological manifestations of COVID-19 are not uncommon, but our study found most resolve with treatment of the underlying infection. Although the timeliness of this review engages current challenges posed by the COVID-19 pandemic, readers must not ignore the limitations and biases intrinsic to an early investigation.

Association Between PSD95 Gene 3'UTR Single Nucleotide Polymorphism and Risk of Acute Ischemic Stroke in Chinese Han Population.

To study the association between the 3'UTR single nucleotide polymorphism of PSD95 gene and the risk of acute ischemic stroke (AIS) in Chinese Han population. PSD95 gene 3'UTR rs191350575, rs314254, rs58197058, rs314253, rs314252, rs188777, rs11652753, rs79715480, and rs13331 genotypes of a total of 280 AIS patients and 280 healthy controls were analyzed. The prognosis outcomes of all AIS patients were analyzed after 3 years of follow-up. The risk of AIS in the rs58197058 locus A allele was 1.76 times higher than the G allele (95%CI 1.53-1.92, p < 0.01). The rs314252 locus A allele carrier was 1.29 times more likely to develop AIS than the G allele (95%CI 1.14-1.45, p < 0.01). The rs13331 locus A allele was a high-risk factor for ASI (adjusted OR = 1.18, 95%CI 1.05-1.33, p = 0.01). The interaction model between Alcohol, DM, Hypertension, rs58197058, and rs314252 predicted the highest accuracy of AIS, with a corresponding sensitivity of 75.36%, specificity of 85.00%, and cross-validation consistency (CVC) of 10/10 (p < 0.01). There was a significant correlation between rs58197058, rs314252, and rs13331 SNPs and plasma FG, TC, HDL-c, and LDL-c levels in AIS patients. The PSD95 gene 3'UTR rs58197058, rs314252, and rs13331 SNPs are associated with the occurrence and prognosis of Chinese Han AIS patients.

Donepezil Improves Gait Performance in Patients with an Acute Cerebral Infarction: A Prospective Observational Cohort Study.

BACKGROUND: Hemiplegia is a common symptom after acute cerebral infarction. OBJECTIVE: This study aimed to explore the influence factors of gait performance and investigate whether donepezil could improve gait performance in patients with an acute cerebral infarction. METHODS: A total of 107 patients who experienced unilateral paresis after an acute cerebral infarction incident were enrolled in this prospectively observational study. Participants underwent a 3- month assessment. At the study's conclusion, patients were divided into 2 groups-those who received donepezil daily (observation Group) and those who did not (Control Group). RESULTS: There was a significant difference (t=3.269, P=0.001) of Wisconsin Gait Scale (WGS) score between single site infarction (27.11±6.65) and multiple sites infarction (31.54±6.42). For gender, smoking, drinking, hypertension, hyperlipidemia and diabetes, there was no difference in WGS scores between subgroups (P>0.05), respectively. The patient's admission National Institute of Health Stroke Scale(NIHSS) score had a strongly positive correlation with WGS score (r=0.850, P<0.001). Besides, age (r=0.218, P=0.024), glycosylated hemoglobin (r=0.274, P=0.004), MMSE (r=-0.261, P=0.007) and Montreal Cognitive Assessment (MoCA) (r=-0.272, P=0.005) had a weak correlation with WGS scores. Multivariate analysis showed age (95% CI: 0.042~0.188, P=0.002), admission NIHSS score (95% CI: 2.405~3.137, P<0.001) and multiple sites infarction (95% CI: 0.044~2.983, P=0.044) were independent risk factors of WGS scores. WGS scores of both observation and control groups gradually decreased after admission (P<0.001). At 3 months after admission, WGS score of the observation group was significantly lower than the control group (t=2.468, P=0.015). There were no significant differences between observation and control group at admission and 1 month after admission (P>0.05) and WGS scores of both single site and multiple sites infarction gradually decreased at one month and three months after admission (P<0.001), while there was no significant difference between two groups (P>0.05). CONCLUSION: Admission NIHSS score, age and multiple sites infarction were independent risk factors of WGS score. Donepezil could improve gait performance in patients with acute cerebral infarction.

Dexmedetomidine attenuates inflammation and pancreatic injury in a rat model of experimental severe acute pancreatitis via cholinergic anti-inflammatory pathway.

BACKGROUND: Excessive inflammatory responses play a critical role in the development of severe acute pancreatitis (SAP), and controlling such inflammation is vital for managing this often fatal disease. Dexmedetomidine has been reported to possess protective properties in inflammatory diseases. Therefore, this study aimed to investigate whether dexmedetomidine pre-treatment exerts an anti-inflammatory effect in rats with SAP induced by sodium taurocholate, and if so, to determine the potential mechanism. METHODS: SAP was induced with sodium taurocholate. Rats received an intraperitoneal injection of dexmedetomidine 30 min before sodium taurocholate administration. α-bungarotoxin, a selective alpha-7 nicotinic acetylcholine receptor (α7nAchR) antagonist, was injected intra-peritoneally 30 min before dexmedetomidine administration. The role of the vagus nerve was evaluated by performing unilateral cervical vagotomy before the administration of dexmedetomidine. Efferent discharge of the vagal nerve was recorded by the BL-420F Data Acquisition & Analysis System. Six hours after onset, serum pro-inflammatory cytokine (tumor necrosis factor α [TNF-α] and interleukin 6 [IL-6]) levels and amylase levels were determined using an enzyme-linked immunosorbent assay and an automated biochemical analyzer, respectively. Histopathological changes in the pancreas were observed after hematoxylin and eosin staining and scored according to Schmidt criteria. RESULTS: Pre-treatment with dexmedetomidine significantly decreased serum levels of TNF-α, IL-6, and amylase, strongly alleviating pathological pancreatic injury in the rat model of SAP (TNF-α: 174.2 ±â€Š30.2 vs. 256.1±42.4 pg/ml; IL-6: 293.3 ±â€Š46.8 vs. 421.7 ±â€Š48.3 pg/ml; amylase: 2102.3 ±â€Š165.3 vs. 3186.4 ±â€Š245.2 U/L). However, the anti-inflammatory and pancreatic protective effects were abolished after vagotomy or pre-administration of α-bungarotoxin. Dexmedetomidine also significantly increased the discharge frequency and amplitude of the cervical vagus nerve in the SAP rat model (discharge frequency: 456.8 ±â€Š50.3 vs. 332.4 ±â€Š25.1 Hz; discharge amplitude: 33.4 ±â€Š5.3 vs. 20.5 ±â€Š2.9 µV). CONCLUSIONS: Dexmedetomidine administration attenuated the systemic inflammatory response and local pancreatic injury caused by SAP in rats through the cholinergic anti-inflammatory pathway involving vagus- and α7nAChR-dependent mechanisms.

Proteomic analysis and comparison of intra­ and extracranial cerebral atherosclerosis responses to hyperlipidemia in rabbits.

The present study aimed to investigate protein expression levels of intra­ and extracranial atherosclerosis in rabbits following administration of a high­fat diet. Rabbits were randomly divided into control (group A; n=9) and high­fat diet (group B; n=9) groups. At week 12, tissues were sectioned from the common carotid artery (CCA) and middle cerebral artery (MCA). Pathological analysis was performed. Differential protein expression levels were examined by 2­D gel electrophoresis (2­DE) and mass spectrometry (MS) analysis and validated by western blotting. Serum lipid levels, the intima­media thickness (IMT) and degree of atherosclerosis of the CCA and MCA were increased at week 12 in the high­fat diet group compared with rabbits that received a normal diet. 2­DE and MS analysis of the protein extracted from CCA and MCA detected >439 different proteins; the expression of 25 proteins was altered, and 8 proteins [albumin A chain, tropomyosin α­1 chain (TPM1), heat shock protein 70 (HSP70), α­smooth muscle actin, ß­galactose binding agglutinin, TPM4 isoform 2, cell keratin 9, single octylic acid glyceride ß­2) demonstrated significant alterations in expression levels. Due to limited antibody sources, only three differentially expressed proteins (TPM1, HSP70 and α­smooth muscle actin) were examined by western blotting. The results of our previous study demonstrated that hyperlipidemia affected the IMT of intracranial and extracranial cerebral arteries. In the present study, protein expression levels of TPM1 and α­smooth muscle actin from extracranial cerebral arteries were significantly increased compared with intracranial cerebral arteries; however, protein expression levels of HSP70 from intracranial cerebral arteries was increased compared with extracranial cerebral arteries. The differences may be closely associated with cell proliferation and metastasis, and oxidoreduction, in intra­ and extracranial cerebral atherosclerosis. HSP70 may have protective properties against atherosclerosis via underlying anti­inflammatory mechanisms, furthermore, differential protein expression levels (TPM1, HSP70 and α­smooth muscle actin) between intra­ and extracranial cerebral arteries may facilitate the identification of novel biological markers for the diagnosis and treatment of cerebral arteriosclerosis.

The value of diffusion kurtosis magnetic resonance imaging for assessing treatment response of neoadjuvant chemoradiotherapy in locally advanced rectal cancer.

OBJECTIVES: To evaluate the feasibility and value of diffusion kurtosis (DK) imaging in assessing treatment response to neoadjuvant chemoradiotherapy (CRT) in patients with locally advanced rectal cancer (LARC). METHODS: Forty-one patients were included. All patients underwent pre- and post-CRT DCE-MRI on a 3.0-Tesla MRI scanner. Imaging indices (D app , K app and ADC values) were measured. Change value (∆X) and change ratio (r∆X) were calculated. Pathological tumour regression grade scores (Mandard) were the standard reference (good responders: pTRG 1-2; poor responders: pTRG 3-5). Diagnostic performance was compared using ROC analysis. RESULTS: For the pre-CRT measurements, pre-D app-10th was significantly lower in the good responder group than that of the poor responder group (p = 0.036). For assessing treatment response to neoadjuvant CRT, pre-D app-10th resulted in AUCs of 0.753 (p = 0.036) with a sensitivity of 66.67 % and a specificity of 77.78 %. The r∆D app had a relatively high AUC (0.859) and high sensitivity (100 %) compared with other image indices. CONCLUSIONS: DKI is feasible for selecting good responders for neoadjuvant CRT for LARC. KEY POINTS: • LARC responded well after neoadjuvant chemoradiotherapy with lower pre-D app-10th . • LARC responded well with greater increases in mean ADC and D app . • The change ratio of D app (r∆D app ) had a relatively better diagnostic performance.

Prognostic aspects of dynamic contrast-enhanced magnetic resonance imaging in synchronous distant metastatic rectal cancer.

OBJECTIVES: To explore the correlations between DCE-MRI quantitative parameters and synchronous distant metastasis and the clinicopathological factors in rectal cancers. METHODS: Sixty-three patients with rectal cancer (synchronous distant metastasis, n = 31; non-metastasis, n = 32) were enrolled in this study. Student's t test and ANOVA were used to compare DCE-MRI parameters (K trans , K ep and V e ). The receiver operating characteristic (ROC) analysis was used to find the reasonable threshold of DCE-MRI parameters to differentiate lesions with synchronous distant metastasis from those without metastasis. RESULTS: The K trans , K ep , and V e value were significantly higher in the lesions with distant metastasis than in the lesions without distant metastasis (0.536 ± 0.242 vs. 0.299 ± 0.118 min-1, p < 0.001; 1.598 ± 0.477 vs. 1.341 ± 0.390 min-1, p = 0.022; and 0.324 ± 0.173 vs. 0.249 ± 0.091, p = 0.034; respectively). The K trans showed the highest AUCs of 0.788 (p < 0.001), with sensitivity of 61.29 % and specificity of 87.5 %, respectively. CONCLUSIONS: DCE-MRI parameters may represent a prognostic indicator for synchronous distant metastases in patients with rectal cancer. KEY POINTS: • The K trans , K ep and V e values correlated with synchronous distant metastasis. • Higher K trans , K ep and V e values were noted among patients with metastasis. • DCE-MRI parameters might represent a prognostic indicator for synchronous distant metastases.

Correlation Between Magnetic Resonance Imaging-Based Evaluation of Extramural Vascular Invasion and Prognostic Parameters of T3 Stage Rectal Cancer.

PURPOSE: The aim of this study was to analyze the correlation between magnetic resonance imaging-based extramural vascular invasion (EMVI) and the prognostic clinical and histological parameters of stage T3 rectal cancers. METHODS: Eighty-six patients with T3 stage rectal cancer who received surgical resection without neoadjuvant therapy were included. Magnetic resonance imaging-based EMVI scores were determined. Correlations between the scores and pretreatment carcinoembryonic antigen levels, tumor differentiation grade, nodal stage, and vascular endothelial growth factor expression were analyzed using Spearman rank coefficient analysis. RESULTS: Magnetic resonance imaging-based EMVI scores were statistically different (P = 0.001) between histological nodal stages (N0 vs N1 vs N2). Correlations were found between magnetic resonance imaging-based EMVI scores and tumor histological grade (rs = 0.227, P = 0.035), histological nodal stage (rs = 0.524, P < 0.001), and vascular endothelial growth factor expression (rs = 0.422; P = 0.016). CONCLUSIONS: Magnetic resonance imaging-based EMVI score is correlated with prognostic parameters of T3 stage rectal cancers and has the potential to become an imaging biomarker of tumor aggressiveness. Magnetic resonance imaging-based EMVI may be useful in helping the multidisciplinary team to stratify T3 rectal cancer patients for neoadjuvant therapies.

Correlation of standard diffusion-weighted imaging and diffusion kurtosis imaging with distant metastases of rectal carcinoma.

PURPOSE: To investigate the correlation of standard diffusion-weighted imaging (DWI) and diffusion kurtosis imaging (DKI) with distant metastases of rectal carcinoma. MATERIALS AND METHODS: Fifty-eight patients with rectal carcinoma (27 with distant metastasis and 31 with no metastasis) were included in this study. The apparent diffusion coefficient (ADC) value from standard DWI (b values of 0 and 1000 sec/mm(2) ), Dapp , and Kapp from DKI (b values of 0, 700, 1400, and 2000 sec/mm(2) ) were acquired with a 3.0T magnetic resonance imaging (MRI) scanner. These quantitative parameters were calculated from the entire tumors. Receiver operating characteristic curve analyses were conducted to assess the utility for discrimination of tumor with distant metastasis and those without metastasis. Parameters were compared using the independent-samples t-test. RESULTS: The histogram metrics 10th percentile of Dapp (Dapp-10th ) and ADC values (ADC10th ) were significantly lower in the distant metastasis group than those without metastasis (972.5 ± 118.8 vs. 1121.3 ± 133.8 × 10(-6) mm(2) /s, P = 0.03; 809.2 ± 67.1 vs. 856.2 ± 72.1 × 10(-6) mm(2) /s, P = 0.03). Dapp-10th showed relatively higher area under the curve (AUC) (0.856 vs. 0.669, P = 0.024), and higher specificity (100% vs. 68%) than ADC10th did for differentiation of lesions with distant metastasis from those without metastasis. CONCLUSION: DKI was relatively better than standard DWI in discriminating rectal carcinoma with distant metastasis from those without metastasis. J. Magn. Reson. Imaging 2016;44:221-229.

[A pilot study of diaphragmatic function evaluated as predictors of weaning in chronic obstructive pulmonary disease patients].

OBJECTIVE: To evaluate the predictive performance of neuro-mechanical coupling (NMC) and neuro-ventilatory coupling (NVC) in the weaning outcome in patients with chronic obstructive pulmonary disease (COPD). METHODS: Sixteen patients were enrolled when the criteria for their first spontaneous breathing trial (SBT) was met. A 30-minute SBT was attempted, with the measurement of electrical activity of the diaphragm (Edi), NMC, NVC, NVC × NMC, index of rapid shallow breathing (f/Vt), airway occlusion pressure (P(0.1)) and f/Vt × P(0.1) at 0, 5 and 30 min. The receiver operating characteristic (ROC) curve was calculated to evaluate the predictive performance of each index. RESULTS: Successful weaning (S group) was observed in 6 patients while weaning failure (F group) in 10 patients. (1) The predictive capacity of Edi: at 30 min of SBT, Edi showed higher values in the F group (P < 0.05), the area under the ROC curves (AUC) was 0.817(P < 0.05). (2) The predictive capacity of NVC and NMC: at 5, 30 min of SBT, NVC and NMC showed higher values in the S group (P < 0.05); at 30 min of SBT NVC presented the largest AUC than any other time of SBT (0.822, P < 0.05), while the AUC of NMC was 0.800(P > 0.05). (3) The predictive capacity of NVC × NMC: at 30 min of SBT, the AUC of NVC × NMC was larger than NVC (0.864, P < 0.05), showing greater sensitivity (100.0%) and specificity (83.3%). (4) The predictive capacity of f/Vt and P(0.1): f/Vt and f/Vt × P(0.1) presented poor predictive performance in the failed patients. CONCLUSIONS: Edi, NVC and NVC × NMC were good predictor for the weaning outcome in patients with COPD.

[Effects of neurally adjusted ventilatory assist on subject-ventilator synchrony in rabbits with acute respiratory distress syndrome].

OBJECTIVE: To observe the effects of neurally adjusted ventilatory assist (NAVA) on subject-ventilator synchrony in rabbits with acute respiratory distress syndrome (ARDS). METHODS: The rabbit model of ARDS was induced by intratracheal infusion of hydrochloric acid. After sufficient recruitment, the rabbits were randomly divided into 2 groups: pressure support ventilation (PSV) group and NAVA group. The parameters of subject-ventilator synchrony such as ventilation trigger, ventilation switching and magnitude of assist were observed at 0, 1, 2, 3 h respectively. RESULTS: (1) Ventilation trigger: 1) trigger delay: the trigger delay in the NAVA group were markedly lower than the PSV group at 0, 1, 2, 3 h (P < 0.05); as ventilation time elapsed, the trigger delay changed neither in NAVA nor in PSV group (P > 0.05). 2) Ineffective trigger index: the ineffective trigger index was 17.7% ± 13.7% in the PSV group. While all neural efforts were trigger, there was no ineffective trigger observed in the NAVA group. (2) Off-cycle delay: the off-cycle delay were significantly lower in the PSV group than that in the NAVA group at 0, 1, 2, 3 h (P < 0.05); as the ventilation time elapsed, the off-cycle delay changed neither in the NAVA group nor in the PSV group (P > 0.05). (3) Magnitude of assist: in the NAVA group, peak EAdi and peak pressure were markedly correlated (determination coefficient 0.86 ± 0.07, P < 0.05). But pressure delivery during the PSV group was not correlated with EAdi (P > 0.05). CONCLUSION: As compared with PSV, NAVA can improve subject-ventilator synchrony in rabbits with ARDS.

[Effects of neurally adjusted ventilatory assist on prevention of ventilator-induced diaphragmatic dysfunction in acute respiratory distress syndrome rabbits].

OBJECTIVE: To evaluate the effect of neurally adjusted ventilatory assist (NAVA) on prevention of ventilator-induced diaphragmatic dysfunction (VIDD) in ARDS rabbits. METHODS: Twenty New Zealand white rabbits were randomly divided into 4 groups: (1) control group (n = 5); (2) Volume control (VC) group (n = 5); (3) Pressure support (PSV) group (n = 5); (4) NAVA group (n = 5). In VC, PSV and NAVA groups, the rabbits were killed and the diaphragm was removed after 4 hours of ventilation. Animals in the control group were not mechanically ventilated, and the diaphragm was also removed immediately after anesthetizing. In all rabbits, malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione (GSH) of diaphragm were measured. Structure of diaphragm was observed by light microscope, electron microscope, constituent ratio and mean cross-sectional area (CSA) of diaphragm fiber. RESULTS: (1) MDA: Compared with the control [(0.15 ± 0.06) nmol/mg], PSV group [(0.30 ± 0.11) nmol/mg], there was no significant difference in MDA of diaphragm in NAVA group [(0.28 ± 0.19) nmol/mg] (F = 2.730, P > 0.05). MDA in VC group [(0.40 ± 0.16) nmol/mg] was significantly higher than the control group (P < 0.05). (2) SOD: Compared with control [(111 ± 12) U/mg], PSV group [(93 ± 4) U/mg], there was no significant difference in SOD of diaphragm in NAVA group [(94 ± 9) U/mg] (F = 4.422, P > 0.05). SOD in VC group [(80 ± 21) U/mg] was significantly lower than the control group (P < 0.05). (3) GSH: Compared with control [(5.3 ± 1.0) mg/g] and PSV group [(4.5 ± 1.2) mg/g], there was no significant difference in GSH of diaphragm in NAVA group [(5.6 ± 1.0) mg/g] (F = 3.001, P > 0.05). GSH in VC group [(3.3 ± 1.7) mg/g] is significantly lower than control and NAVA groups (P < 0.05). (4) Light microscope: In VC group, many changes were observed in the muscle, such as myelofibrosis, necrosis, and some of muscle fibers became atrophy, but these were no obvious changes of pathological structure in control, PSV or NAVA groups. (5) Electron microscope: In control, PSV and NAVA groups, the ultrastructure of diaphragm was normal. Different from the above 3 groups, some abnormal ultrastructure was observed in VC group, including disrupted myofibrils, swollen mitochondria. (6) CSA of diaphragm fiber: Compared with control and PSV group, there was no significant difference in CSA of diaphragm fiber in NAVA group (P > 0.05); The CSA of type II fibers in VC group was markedly lower than control group (P < 0.05). CONCLUSIONS: Compared with volume control ventilation, NAVA may mitigate diaphragmatic oxidative stress, atrophy and injury, and prevent VIDD better than VC.

Effects of pulmonary stretch reflex on lung injury in rabbits with acute respiratory distress syndrome.

BACKGROUND: Pulmonary stretch reflex plays an important role in regulation of respiratory movement. This study aimed to evaluate the effect of pulmonary stretch reflex on lung injury in rabbits with acute respiratory distress syndrome (ARDS). METHODS: ARDS rabbits were given intratracheal infusion of hydrochloric acid and ventilated with neurally adjusted ventilatory assistance (NAVA) with a tidal volume (VT) of 6 mL/kg and the electrical activity of diaphragm (EAdi)-determined positive end expiratory pressure. After isolation of the bilateral vagus nerve trunk, the rabbits were randomized into two groups: sham operation (SHAM) group (n=5) and bilateral vagotomy (VAG) group (n=5). Gas exchange and respiratory mechanics were detected at baseline, after lung injury and 1, 2, and 3 hours after ventilation respectively. Pulmonary permeability index, pathological changes and inflammatory response were also measured. RESULTS: Compared with the SHAM group, PaO2/FiO2 in the VAG group decreased significantly 2 and 3 hours after ventilation (P<0.05). There was no significant difference in PaCO2 between the SHAM and VAG groups (P>0.05), and the VAG group had a high VT, peak pressure (Ppeak), and mean pressure (Pm) compared with the SHAM group 1, 2, 3 hours after ventilation (P<0.05). Compared to the SHAM group, dead space fraction (VD/VT) and respiratory system elastance (Ers) in the VAG group increased (P<0.05) and static pulmonary compliance (Cst) decreased markedly (P<0.05) after ventilation for 3 hours. Lung wet/dry weight ratio (W/D) (8.4±1.2 vs. 6.6±1.0), lung injury score (6.3±1.8 vs. 3.8±1.3), tumor necrosis factor-α (TNF-α) (779±372 pg/mL vs. 355±130 pg/mL) and interleukin-8 (IL-8) (169±21 pg/mL vs. 118±17 pg/mL) increased significantly in the VAG group compared with the SHAM group (P<0.05). CONCLUSION: Lung injury is aggravated after bilateral vagotomy, demonstrating that pulmonary stretch reflex may have protective effect on the lung.

[Effects of electrical activity of diaphragm on the titration of positive end-expiratory pressure in a model of acute respiratory distress syndrome].

OBJECTIVE: To explore the relationship of electrical activity of diaphragm (EAdi) and positive end-expiratory pressure (PEEP) in a rabbit model of acute respiratory distress syndrome (ARDS). METHODS: The rabbit model of ARDS was induced by an intratracheal infusion of hydrochloric acid. After a sufficient amount of recruitment maneuvers (RM), the level: the PEEP levels were (10.4 ± 1.0) cm H2O in EAdi group and (9.7 ± 2.1) cm H2O in rabbits were divided into 2 groups: (1) PEEP titration with EAdi (EAdi group); (2) PEEP titration with maximum oxygenation (maximum oxygenation group). The tidal volume was 6 ml/kg in 2 groups. Pulmonary mechanics, gas exchange and hemodynamic were observed in two groups at baseline, after lung injury and ventilation 1, 2, 3 h respectively. RESULTS: (1) PEEP maximum oxygenation group. There was no significant difference between two groups (P > 0.05). (2) Pulmonary mechanics:there was no significant difference in peak pressure (Ppeak) and mean pressure (Pm) between two groups at ventilation 1, 2, 3 h (P > 0.05). (3) Gas exchange: at ventilation 1, 2, 3 h, the oxygenation index (PaO2/FiO2) in EAdi group was higher than that of after lung injury (P < 0.05) and there was no significant difference in PaO2/FiO2 and partial pressure of arterial carbon dioxide (PaCO2) between two groups (P > 0.05). (4) Hemodynamic: at ventilation 1, 2, 3 h, the heart rate (HR) and mean artery pressure (MAP) in EAdi group had no significant differences with baseline, after lung injury and maximum oxygenation group (P > 0.05). CONCLUSION: EAdi may be an ideal method for PEEP titration at post-RM in an ARDS model.