[Impact of systolic blood pressure on visit-to-visit blood pressure variability in middle-aged and elderly people].

OBJECTIVE: To observe the impact of systolic blood pressure (SBP) on visit-to-visit blood pressure variability (BPV) in middle-aged and elderly people. METHODS: Visit-to-visit BPV was determined in 5440 workers in the Kailuan study cohort from 2006 to 2007. The subjects were ≥ 40 years-old and had no history of stroke, transient ischemic attack or myocardial infarction. Participants were divided into five groups according to different levels of SBP. Linear regression was used to analyze the related factors which might affect BPV. RESULTS: Mean systolic BPV of all subjects was 10.35 mm Hg [coefficient of variation (CV 7.96%)]. The mean systolic BPV of males was 10.54 mm Hg (CV 7.90%) while the mean SBPV of females was 10.06 mm Hg (CV 7.90%). The BPV of males was significant higher than that of females (P < 0.001). CV of SBP was similar between males and females. Furthermore, higher SBP was associated with higher BPV. There were significant differences in BPV between different groups with different levels of SBP (P < 0.001). Linear regression analysis demonstrated that SBP, age, gender, high-sensitivity C-reactive protein (hsCRP) were affecting factors of BPV. Twenty mm Hg SBP increase was linked with 2.02 mm Hg BPV increase and 0.388%CV increase. Age increase of 1 year was associated with 0.044 mm Hg BPV increase and 0.029% CV increase. CONCLUSION: SBP, age, gender and hsCRP are important factors affecting BPV in middle-aged and elderly people. Higher SBP is closely related to greater BPV in this cohort.

[Role of prone position mechanical ventilation in patients with acute respiratory distress syndrome originating from pulmonary disease and extra-pulmonary disease].

OBJECTIVE: To assess the effect of mechanical ventilation on prone position for the treatment of acute respiratory distress syndrome (ARDS) originating from pulmonary disease and extra-pulmonary disease. METHODS: From January 2001 to February 2004 in intensive care unit (ICU), 42 patients with ARDS were divided into pulmonary disease group and extra-pulmonary disease group. All the patients were mechanically ventilated on prone position. Arterial blood gases, respiratory rate (RR), fraction of inspired oxygen (FiO(2)), pulmonary compliance (C), tidal volume (V(T)), airway resistance (Raw) were measured before prone position and 2 hours and 4 hours after prone position. Lung-CT was measured in supine position and prone position. RESULTS: When patients were turned to prone position, SaO(2) and RR were decreased markedly in two groups. V(T) was increased in extra-pulmonary disease groups compared with pulmonary disease group at the same time. Oxygen index, hemoglobin oxygen saturation and Raw were increased markedly when patients were turned to prone position, and oxygen index of pulmonary disease group was higher than that of extra-pulmonary disease group at the same time. No change was found in blood pH and partial pressure of carbon dioxide in artery (PaCO(2)), but oxygenation was improved markedly in two groups. The effective rate of improved oxygenation was 65% in pulmonary disease group and 68% in extrapulmonary disease group, but no significant difference was found. Lung CT revealed that when the patients were in prone position, the degree of lung infiltration in the dorsal part of lung decreased while that in the ventral part increased. CONCLUSION: Oxygenation is improved markedly in prone position in two groups. Mechanical ventilation on prone position was an effective method in the treatment of ARDS patients.

[The effect of neuromuscular blocking agents on prognosis of patients with acute respiratory distress syndrome: a meta analysis].

OBJECTIVE: To determine the effects of neuromuscular blocking agent (NMBA) on prognosis of patients with acute respiratory distress syndrome (ARDS). METHODS: PubMed database, the Cochrane Library, EMBASE, Excepta Media, CBM, CNKI and other sources were used for retrieving the pertinent literature. All randomized controlled trials (RCTs) on NMBA treating ARDS patients were enrolled. The Cochrance Collaboration's software RevMan 5.0 was used for data analysis. Two authors independently extracted data and assessed study quality using standardized instruments. RESULTS: Three studies were included in the final analysis, providing a sample of 431 patients. The combined results demonstrated a decrease in 28 days mortality [Peto odds ratio (OR) =0.57, 95% confidence interval (95%CI) 0.37-0.88, P=0.01] and lower incidence of barotrauma (OR=0.42, 95%CI 0.20-0.91,P=0.003) after NMBA treatment for patients with ARDS as compared with control group. The incidence of acquired neuromyopathy was similar between NMBA group and control group (OR=1.20, 95%CI 0.67-2.14, P=0.54). As compared with the control group at 48 hours, there was no statistical difference in ventilator parameters including total positive end expiratory pressure (PEEP, OR=0.09, 95%CI -0.50-0.68, P=0.77) and plateau pressure (Pplat, OR=0.62, 95%CI -0.32-1.57, P=0.20). There was no heterogeneity (P>0.1, I (2)<50%). At 120 hours after NMBA treatment, the total PEEP was significantly lower than that of control group (OR=-1.22, 95%CI -2.39 to -0.04, P=0.04), and the difference in Pplat showed statistical difference compared with the control group (OR=-2.61, 95%CI -4.50 to -0.73, P=0.007). CONCLUSION: Early administration of NMBA for ARDS patients results in a significant reduction in 28 days mortality, and it improves outcome.