Examining the haemodynamic repercussions of ventilator hyperinflation in elderly patients: An explanatory study.

This study assessed the cardiovascular repercussions of two VHI (ventilation hyperinflation) protocols using the volume-controlled mode, one with an inspiratory pause (VHI-P) and the other without an inspiratory pause (VHI-NP), in mechanically ventilated elderly patients. The patients underwent both VHI protocols in a randomized order, and impedance cardiography was used to record cardiovascular variables. During VHI-P, the diastolic blood pressure was lower than during VHI-NP (Δ = 10%; p = 0.009). VHI-NP and VHI-P demonstrated a decrease in cardiac output (CO) during the first and third sets compared to baseline (p < 0.05; ES=0.23 and 0.29, respectively). Arterial oxygen delivery decreased simultaneously with CO compared to baseline values (p < 0.05; ES=0.22 and 0.23, respectively). Five minutes after the intervention, the systolic time ratio values were lower for VHI-P than VHI-NP (Δ = 10%; p = 0.01). Left ventricular ejection time values were consistently lower in VHI-NP compared to VHI-P (Δ = 2%; p = 0.02). In conclusion, our study shows that VHI in volume-controlled mode induces hemodynamic changes in mechanically ventilated elderly patients, albeit with a small effect size and within the normal range.

Agreement between wireless and standard measurements of vital signs in acute exacerbation of chronic obstructive pulmonary disease: a clinical validation study.

Objective.Wireless sensors for continuous monitoring of vital signs have potential to improve patient care by earlier detection of deterioration in general ward patients. We aimed to assess agreement between wireless and standard (wired) monitoring devices in patients hospitalized with acute exacerbation of chronic obstructive pulmonary disease (AECOPD).Approach.Paired measurements of vital signs were recorded with 15 min intervals for two hours. The primary outcome was agreement between wireless and standard monitor measurements using the Bland and Altman method to calculate bias with 95% limits of agreement (LoA). We considered LoA of less than ±5 beats min-1(bpm) acceptable for heart rate (HR), whereas agreement of peripheral oxygen saturation (SpO2), respiratory rate (RR), and blood pressure (BP) were acceptable if within ±3%-points, ±3 breaths min-1(brpm), and ±10 mmHg, respectively.Main results.180 sample-pairs of vital signs from 20 with AECOPD patients were recorded for comparison. The wireless versus standard monitor bias was 0.03 (LoA -3.2 to 3.3) bpm for HR measurements, 1.4% (LoA -0.7% to 3.6%) for SpO2, -7.8 (LoA -22.3 to 6.8) mmHg for systolic BP and -6.2 (LoA -16.8 to 4.5) mmHg for diastolic BP. The wireless versus standard monitor bias for RR measurements was 0.75 (LoA -6.1 to 7.6) brpm.Significance.Commercially available wireless monitors could accurately measure HR in patients admitted with AECOPD compared to standard wired monitoring. Agreement for SpO2were borderline acceptable while agreement for RR and BP should be interpreted with caution.

The effect of acute magnesium loading on the maximal exercise performance of stable chronic obstructive pulmonary disease patients

OBJECTIVE: The potential influence of magnesium on exercise performance is a subject of increasing interest. Magnesium has been shown to have bronchodilatatory properties in asthma and chronic obstructive pulmonary disease patients. The aim of this study was to investigate the effects of acute magnesium IV loading on the aerobic exercise performance of stable chronic obstructive pulmonary disease patients. METHODS: Twenty male chronic obstructive pulmonary disease patients (66.2 + 8.3 years old, FEV1: 49.3+19.8%) received an IV infusion of 2 g of either magnesium sulfate or saline on two randomly assigned occasions approximately two days apart. Spirometry was performed both before and 45 minutes after the infusions. A symptom-limited incremental maximal cardiopulmonary test was performed on a cycle ergometer at approximately 100 minutes after the end of the infusion. ClinicalTrials.gov: NCT00500864 RESULTS: Magnesium infusion was associated with significant reductions in the functional residual capacity (-0.41 l) and residual volume (-0.47 l), the mean arterial blood pressure (-5.6 mmHg) and the cardiac double product (734.8 mmHg.bpm) at rest. Magnesium treatment led to significant increases in the maximal load reached (+8 w) and the respiratory exchange ratio (0.06) at peak exercise. The subgroup of patients who showed increases in the work load equal to or greater than 5 w also exhibited significantly greater improvements in inspiratory capacity (0.29 l). CONCLUSIONS: The acute IV loading of magnesium promotes a reduction in static lung hyperinflation and improves the exercise performance in stable chronic obstructive pulmonary disease patients. Improvements in respiratory mechanics appear to be responsible for the latter finding.

Strategies for cardiopulmonary exercise testing of pectus excavatum patients: [review]

The purpose of this paper is to provide strategies for cardiopulmonary exercise testing of pectus excavatum patients. Currently, there are no standardized methods for assessing cardiovascular and pulmonary responses in this population; therefore, making comparisons across studies is difficult if not impossible. These strategies are intended for physicians, pulmonary technicians, exercise physiologists, and other healthcare professionals who conduct cardiopulmonary exercise testing on pectus excavatum patients. By using the strategies outlined in this report, comparisons across studies can be made, and the effects of pectus excavatum on cardiopulmonary function can be assessed with greater detail.

The study of the relationship between the angiotensin-converting enzyme gene insertion/deletion polymorphism and the cardiorespiratory fitness / 中华老年医学杂志

Objective To explore the relationship between the angiotensin-converting enzyme(ACE) gene inserton/deletion(I/D) polymorphism and the cardiorespiratory fitness. Methods One hundred twenty six male subjects were recruited and randomized into a physical exercise(n=65) or a control group(n=61).The men in the physical exercise group were trained with mild-moderate intensity physical exercise for 5 years. The men in the control group were advised to make their personal choice whether or not to engage in physical exercise. The cardiorespiratory fitness indices,e.g. aerobic threshold were measured at baseline and annually. The I/D polymorphism in the 16 th intron of ACE gene was analysed by polymerase chain reaction. Results At baseline, the aerobic threshold was (14.4 ? 3.9)ml?min -1?kg -1 in the physical exercise group. After 5-year physical exercise, the aerobic threshold was (16.4 ? 4.1)ml?min -1?kg -1in the physical exercise group. At baseline, the aerobic thresholds was(14.2 ?3.6)ml?min -1?kg -1in the control group. After 5 years, the aerobic threshold was(13.8 ? 3.3)ml?min -1?kg -1in the control group. After 5 year physical exercise, compared with the baseline and the control group, the aerobic threshold increased significantly in the physical exercise group(both,P0.05). Conclusions Regular low to moderate intensity physical exercise can increase aerobic threshold and improve cardiorespiratory fitness. Compared with the subjects with the ACE DD genotypes, the cardiorespiratory fitness can be improved more easily for the subjects with the ACE II,ID genotypes.