scholarly journals Influence of lung aeration on diaphragmatic contractility during a spontaneous breathing trial: an ultrasound study

2019 ◽  
Vol 7 (1) ◽  
Author(s):  
Jing Xia ◽  
Chuan-Yun Qian ◽  
Li Yang ◽  
Mei-Ju Li ◽  
Xiao-Xue Liu ◽  
...  
Keyword(s):  
Mechanical Ventilation ◽  
Spontaneous Breathing ◽  
Spontaneous Breathing Trial ◽  
Quiet Breathing ◽  
Diaphragmatic Function ◽  
Lung Aeration ◽  
Ultrasound Study ◽  
Weaning Failure ◽  
Successful Weaning ◽  
The Right

Abstract Background A spontaneous breathing trial (SBT) is a major diagnostic tool to predict successfully extubation in patients. Several factors may lead to weaning failure, including the degree of lung aeration loss and diaphragm dysfunction. The main objective was to compare the diaphragmatic contractility between patients with high lung aeration loss and low lung aeration loss during a 30-minute SBT by ultrasound. Methods This was a prospective single-center study. Lung ultrasound aeration score (LUS) and diaphragmatic thickening fraction (DTF) were measured during mechanical ventilation 1 h before SBT (T-1), 30 min (T1), and 120 min (T2) after the start of the SBT during quiet breathing. The right and left DTF were compared between patients with LUS ≥ 14 (high lung aeration loss), considered at high risk of post-extubation distress, and those with LUS < 14 (low lung aeration loss). The relationship between the LUS and DTF and the changes in LUS and DTF from T-1 to T2 in patients with LUS ≥ 14 were assessed. Results Forty-nine patients were analyzed; 33 had LUS ≥ 14 and 16 had LUS < 14 at T1. The DTF at T1 was significantly higher in patients with LUS ≥ 14 than in those with LUS < 14: the right median (IQR) DTF was 22.2% (17.1 to 30.9%) vs. 14.8% (10.2 to 27.0%) (p = 0.035), and the left median (IQR) DTF was 25.0% (18.4 to 35.0%) vs. 18.6% (9.7 to 24.2%) (p = 0.017), respectively. There was a moderate positive correlation between the LUS and the DTF (Rho = 0.3, p = 0.014). A significant increase in the LUS was observed from T-1 to T1, whereas no change was found between T1 and T2. The DTF remained stable from T-1 to T2. Conclusions During a SBT, diaphragmatic contraction acts differently depending on the degree of pulmonary aeration. In patients with high lung aeration loss, increased diaphragmatic contractility indicates an additional respiratory effort to compensate lung volume loss that would contribute to successful SBT. Further studies are needed to evaluate the combined evaluation of lung aeration and diaphragmatic function to predict the successful weaning of patients from mechanical ventilation.

scholarly journals Product of driving pressure and respiratory rate for predicting weaning outcomes

2021 ◽  
Vol 49 (5) ◽  
pp. 030006052110100
Author(s):  
Ju Gong ◽  
Bibo Zhang ◽  
Xiaowen Huang ◽  
Bin Li ◽  
Jian Huang
Keyword(s):  
Mechanical Ventilation ◽  
Respiratory Rate ◽  
Spontaneous Breathing ◽  
Spontaneous Breathing Trial ◽  
Plateau Pressure ◽  
Driving Pressure ◽  
Failure Group ◽  
Rapid Shallow Breathing Index ◽  
Weaning Failure ◽  
Shallow Breathing

Objective Clinicians cannot precisely determine the time for withdrawal of ventilation. We aimed to evaluate the performance of driving pressure (DP)×respiratory rate (RR) to predict the outcome of weaning. Methods Plateau pressure (Pplat) and total positive end-expiratory pressure (PEEPtot) were measured during mechanical ventilation with brief deep sedation and on volume-controlled mechanical ventilation with a tidal volume of 6 mL/kg and a PEEP of 0 cmH2O. Pplat and PEEPtot were measured by patients holding their breath for 2 s after inhalation and exhalation, respectively. DP was determined as Pplat minus PEEPtot. The rapid shallow breathing index was measured from the ventilator. The highest RR was recorded within 3 minutes during a spontaneous breathing trial. Patients who tolerated a spontaneous breathing trial for 1 hour were extubated. Results Among the 105 patients studied, 44 failed weaning. During ventilation withdrawal, DP×RR was 136.7±35.2 cmH2O breaths/minute in the success group and 230.2±52.2 cmH2O breaths/minute in the failure group. A DP×RR index >170.8 cmH2O breaths/minute had a sensitivity of 93.2% and specificity of 88.5% to predict failure of weaning. Conclusions Measurement of DP×RR during withdrawal of ventilation may help predict the weaning outcome. A high DP×RR increases the likelihood of weaning failure. Statement: This manuscript was previously posted as a preprint on Research Square with the following link: https://www.researchsquare.com/article/rs-15065/v3 and DOI: 10.21203/rs.2.24506/v3

scholarly journals Mechanical power normalized to lung-thorax compliance indicates weaning readiness in prolonged ventilated patients

2022 ◽  
Vol 12 (1) ◽  
Author(s):  
Alessandro Ghiani ◽  
Joanna Paderewska ◽  
Swenja Walcher ◽  
Konstantinos Tsitouras ◽  
Claus Neurohr ◽  
...  
Keyword(s):  
Mechanical Ventilation ◽  
Logistic Regression ◽  
Respiratory System ◽  
Spontaneous Breathing ◽  
Characteristic Curve ◽  
Spontaneous Breathing Trial ◽  
Mechanical Power ◽  
Binary Logistic Regression Model ◽  
Weaning Failure ◽  
Ventilated Patients

AbstractSince critical respiratory muscle workload is a significant determinant of weaning failure, applied mechanical power (MP) during artificial ventilation may serve for readiness testing before proceeding on a spontaneous breathing trial (SBT). Secondary analysis of a prospective, observational study in 130 prolonged ventilated, tracheotomized patients. Calculated MP’s predictive SBT outcome performance was determined using the area under receiver operating characteristic curve (AUROC), measures derived from k-fold cross-validation (likelihood ratios, Matthew's correlation coefficient [MCC]), and a multivariable binary logistic regression model. Thirty (23.1%) patients failed the SBT, with absolute MP presenting poor discriminatory ability (MCC 0.26; AUROC 0.68, 95%CI [0.59‒0.75], p = 0.002), considerably improved when normalized to lung-thorax compliance (LTCdyn-MP, MCC 0.37; AUROC 0.76, 95%CI [0.68‒0.83], p < 0.001) and mechanical ventilation PaCO2 (so-called power index of the respiratory system [PIrs]: MCC 0.42; AUROC 0.81 [0.73‒0.87], p < 0.001). In the logistic regression analysis, PIrs (OR 1.48 per 1000 cmH2O2/min, 95%CI [1.24‒1.76], p < 0.001) and its components LTCdyn-MP (1.25 per 1000 cmH2O2/min, [1.06‒1.46], p < 0.001) and mechanical ventilation PaCO2 (1.17 [1.06‒1.28], p < 0.001) were independently related to SBT failure. MP normalized to respiratory system compliance may help identify prolonged mechanically ventilated patients ready for spontaneous breathing.

scholarly journals Diaphragm dysfunction, lung aeration loss and weaning-induced pulmonary oedema in difficult-to-wean patients

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Martin Dres ◽  
Emmanuel Rozenberg ◽  
Elise Morawiec ◽  
Julien Mayaux ◽  
Julie Delemazure ◽  
...  
Keyword(s):  
Pulmonary Oedema ◽  
Spontaneous Breathing ◽  
Spontaneous Breathing Trial ◽  
Pulmonary Artery Occlusion Pressure ◽  
Artery Occlusion ◽  
Diaphragm Dysfunction ◽  
Lung Aeration ◽  
Tracheal Pressure ◽  
Weaning Failure ◽  
Phrenic Nerves

Abstract Background Diaphragm dysfunction and weaning-induced pulmonary oedema are commonly involved during weaning failure, but their physiological interactions have been poorly reported. Our hypothesis was that diaphragm dysfunction is not particularly associated with weaning-induced pulmonary oedema. Methods It was a single-centre and physiological study conducted in patients who had failed a first spontaneous breathing trial and who underwent a second trial. The diaphragm function was evaluated by measuring the tracheal pressure generated in response to a bilateral magnetic phrenic nerves stimulations. Weaning-induced pulmonary oedema was diagnosed in case of failure of the spontaneous breathing trial if patients exhibited signs of plasma concentration or echocardiographic diagnosis of pulmonary artery occlusion pressure elevation. Results Fifty-three patients were included and 31/53 (58%) failed the spontaneous breathing trial, including 24/31 (77%) patients with weaning-induced pulmonary oedema. Diaphragm dysfunction was present in 33/53 (62%) patients. Diaphragm dysfunction or weaning-induced pulmonary oedema were present in 26/31 (84%) of the patients who failed the spontaneous breathing trial. Weaning-induced pulmonary oedema occurred in 20/33 (61%) patients with a diaphragm dysfunction and in 4/20 (20%) patients without (p = 0.005). Conclusion Weaning-induced pulmonary oedema was three times more frequent in case of diaphragm dysfunction. Even in case of diaphragm dysfunction, physicians might be encouraged to investigate the presence of weaning-induced pulmonary oedema during weaning failure.

Weaning failure in critical illness

2016 ◽  
Author(s):  
Annalisa Carlucci ◽  
Paolo Navalesi
Keyword(s):  
Mechanical Ventilation ◽  
Spontaneous Breathing ◽  
Respiratory Muscle ◽  
Prolonged Mechanical Ventilation ◽  
Spontaneous Breathing Trial ◽  
Extubation Failure ◽  
High Morbidity ◽  
Weaning Failure ◽  
Generating Capacity ◽  
The One

Weaning failure has been defined as failure to discontinue mechanical ventilation, as assessed by the spontaneous breathing trial, or need for re-intubation after extubation, so-called extubation failure. Both events represent major clinical and economic burdens, and are associated with high morbidity and mortality. The most important mechanism leading to discontinuation failure is an unfavourable balance between respiratory muscle capacity and the load they must face. Beyond specific diseases leading to loss of muscle force-generating capacity, other factors may impair respiratory muscle function, including prolonged mechanical ventilation, sedation, and ICU-acquired neuromuscular dysfunction, potentially consequent to multiple factors. The load depends on the mechanical properties of the respiratory system. An increased load is consequent to any condition leading to increased resistance, reduced compliance, and/or occurrence of intrinsic positive-end-expiratory pressure. Noteworthy, the load can significantly increase throughout the spontaneous breathing trial. Cardiac, cerebral, and neuropsychiatric disorders are also causes of discontinuation failure. Extubation failure may depend, on the one hand, on a deteriorated force-load balance occurring after removal of the endotracheal tube and, on the other hand, on specific problems. Careful patient evaluation, avoidance and treatment of all the potential determinants of failure are crucial to achieve successful discontinuation and extubation.

Prevalence and Impact on Weaning of Pleural Effusion at the Time of Liberation from Mechanical Ventilation

2017 ◽  
Vol 126 (6) ◽  
pp. 1107-1115 ◽  
Author(s):  
Martin Dres ◽  
Damien Roux ◽  
Tài Pham ◽  
Alexandra Beurton ◽  
Jean-Damien Ricard ◽  
...  
Keyword(s):  
Intensive Care Unit ◽  
Mechanical Ventilation ◽  
Intensive Care ◽  
Pleural Effusion ◽  
Spontaneous Breathing ◽  
Odds Ratio ◽  
Spontaneous Breathing Trial ◽  
Ventilatory Support ◽  
Weaning Failure ◽  
Weaning Outcome

Abstract Background Pleural effusion is frequent in intensive care unit patients, but its impact on the outcome of weaning remains unknown. Methods In a prospective study performed in three intensive care units, pleural ultrasound was performed at the first spontaneous breathing trial to detect and quantify pleural effusion (small, moderate, and large). Weaning failure was defined by a failed spontaneous breathing trial and/or extubation requiring any form of ventilatory support within 48 h. The primary endpoint was the prevalence of pleural effusion according to weaning outcome. Results Pleural effusion was detected in 51 of 136 (37%) patients and was quantified as moderate to large in 18 (13%) patients. As compared to patients with no or small pleural effusion, their counterparts were more likely to have chronic renal failure (39 vs. 7%; P = 0.01), shock as the primary reason for admission (44 vs. 19%; P = 0.02), and a greater weight gain (+4 [0 to 7] kg vs. 0 [−1 to 5] kg; P = 0.02). The prevalence of pleural effusion was similar in weaning success and weaning failure patients (odds ratio, 1.23; 95% CI, 0.61 to 2.49; P = 0.56), as was the prevalence of moderate to large pleural effusion (odds ratio, 0.89; 95% CI, 0.33 to 2.41; P = 1.00). Duration of mechanical ventilation and intensive care unit length of stay were similar between patients with no or small pleural effusion and those with moderate to large pleural effusion. Conclusions Significant pleural effusion was observed in 13% of patients at the time of liberation from mechanical ventilation and was not associated with an alteration of weaning outcome. (Anesthesiology 2017; 126:1107–15)

scholarly journals Cardiopulmonary coupling indices to assess weaning readiness from mechanical ventilation

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Pablo Armañac-Julián ◽  
David Hernando ◽  
Jesús Lázaro ◽  
Candelaria de Haro ◽  
Rudys Magrans ◽  
...  
Keyword(s):  
Heart Rate ◽  
Mechanical Ventilation ◽  
Spontaneous Breathing Trial ◽  
Sinus Arrhythmia ◽  
Time Frequency ◽  
Cardiopulmonary Coupling ◽  
Cardiac Pumping ◽  
Successful Weaning ◽  
Frequency Coherence ◽  
Subspace Projections

AbstractThe ideal moment to withdraw respiratory supply of patients under Mechanical Ventilation at Intensive Care Units (ICU), is not easy to be determined for clinicians. Although the Spontaneous Breathing Trial (SBT) provides a measure of the patients’ readiness, there is still around 15–20% of predictive failure rate. This work is a proof of concept focused on adding new value to the prediction of the weaning outcome. Heart Rate Variability (HRV) and Cardiopulmonary Coupling (CPC) methods are evaluated as new complementary estimates to assess weaning readiness. The CPC is related to how the mechanisms regulating respiration and cardiac pumping are working simultaneously, and it is defined from HRV in combination with respiratory information. Three different techniques are used to estimate the CPC, including Time-Frequency Coherence, Dynamic Mutual Information and Orthogonal Subspace Projections. The cohort study includes 22 patients in pressure support ventilation, ready to undergo the SBT, analysed in the 24 h previous to the SBT. Of these, 13 had a successful weaning and 9 failed the SBT or needed reintubation –being both considered as failed weaning. Results illustrate that traditional variables such as heart rate, respiratory frequency, and the parameters derived from HRV do not differ in patients with successful or failed weaning. Results revealed that HRV parameters can vary considerably depending on the time at which they are measured. This fact could be attributed to circadian rhythms, having a strong influence on HRV values. On the contrary, significant statistical differences are found in the proposed CPC parameters when comparing the values of the two groups, and throughout the whole recordings. In addition, differences are greater at night, probably because patients with failed weaning might be experiencing more respiratory episodes, e.g. apneas during the night, which is directly related to a reduced respiratory sinus arrhythmia. Therefore, results suggest that the traditional measures could be used in combination with the proposed CPC biomarkers to improve weaning readiness.

Mechanical Ventilation: Approaches and Special Considerations

2018 ◽  
Author(s):  
Adrian A. Maung ◽  
Lewis J Kaplan
Keyword(s):  
Mechanical Ventilation ◽  
Respiratory Failure ◽  
Acute Respiratory Failure ◽  
Key Words ◽  
Spontaneous Breathing ◽  
Functional Unit ◽  
Spontaneous Breathing Trial

In this chapter, we complete the discussion of mechanical ventilation by examining approaches to mechanical ventilation for different patient populations and how to assess whether a patient is ready for liberation from mechanical ventilation. Each of the three chapters is intended to build on the preceding one and therefore establishes a functional unit with regard to mechanical ventilation, whether it is provided in an invasive or a noninvasive fashion.  This review contains 1 Figure, 1 Table and 31 references Key Words: acute respiratory failure, ARDS, mechanical ventilation liberation, spontaneous breathing trial, tracheostomy 

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