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 Mechanical power normalized to lung-thorax compliance predicts prolonged ventilation weaning failure: a prospective study

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Alessandro Ghiani ◽  
Joanna Paderewska ◽  
Swenja Walcher ◽  
Claus Neurohr
Keyword(s):  
Mechanical Ventilation ◽  
Respiratory System ◽  
Prolonged Mechanical Ventilation ◽  
Minute Ventilation ◽  
Characteristic Curve ◽  
Mechanical Power ◽  
Likelihood Ratios ◽  
Arterial Blood Gas ◽  
Arterial Blood ◽  
Weaning Failure

Abstract Background Mechanical power (MP) of artificial ventilation, the energy transferred to the respiratory system, is a chief determinant of adequate oxygenation and decarboxylation. Calculated MP, the product of applied airway pressure and minute ventilation, may serve as an estimate of respiratory muscle workload when switching to spontaneous breathing. The aim of the study was to assess MP’s discriminatory performance in predicting successful weaning from prolonged tracheostomy ventilation. Methods Prospective, observational study in 130 prolonged mechanically ventilated, tracheotomized patients in a specialized weaning center. Predictive weaning outcome ability of arterial blood gas analyses and indices derived from calculated MP at beginning and end of weaning was determined in terms of area under receiver operating characteristic curve (AUROC) and measures derived from k-fold cross-validation (likelihood ratios, diagnostic odds ratio, F1 score, and Matthews correlation coefficient [MCC]). Results Forty-four (33.8%) patients experienced weaning failure. Absolute MP showed poor discrimination in predicting outcome; whereas specific MP (MP normalized to dynamic lung-thorax compliance, LTCdyn-MP) had moderate diagnostic accuracy (MCC 0.38; AUROC 0.79, 95%CI [0.71‒0.86], p < 0.001), further improved by correction for corresponding mechanical ventilation PaCO2 (termed the power index of the respiratory system [PIrs]: MCC 0.52; AUROC 0.86 [0.79‒0.92], p < 0.001). Diagnostic performance of MP indices increased over the course of weaning, with maximum accuracy immediately before completion (LTCdyn-MP: MCC 0.49; AUROC 0.86 [0.78‒0.91], p < 0.001; PIrs: MCC 0.68; AUROC 0.92 [0.86‒0.96], p < 0.001). Conclusions MP normalized to dynamic lung-thorax compliance, a surrogate for applied power per unit of ventilated lung volume, accurately discriminated between low and high risk for weaning failure following prolonged 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 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 THE IDEAL PROFILE (INCREASE IN B-LINES/DELTA B-LINES) ON LUNG ULTRASOUND FOR DIAGNOSING WEANING INDUCED PULMONARY EDEMA IN VENTILATED PATIENTS

2022 ◽  
Vol 71 (6) ◽  
pp. 2220-23
Author(s):  
Ghulam Rasheed ◽  
Zahid Siddique Shad ◽  
Tooba Mehreen ◽  
Nusrat Kharadi ◽  
Moazma Ramzan ◽  
...  
Keyword(s):  
Mechanical Ventilation ◽  
Pulmonary Edema ◽  
Spontaneous Breathing ◽  
Lung Ultrasound ◽  
Weaning Failure ◽  
Before And After ◽  
Spontaneous Breathing Trials ◽  
B Lines ◽  
Ventilated Patients ◽  
The Ideal

Objective: To ascertain the ideal number of B-lines on lung ultrasound for the diagnosis of weaning induced pulmonary edema in ventilated patients. Study Design: Prospective observational study. Place and Duration of Study: Department of Medicine, Shifa International Hospital, Islamabad, from Jan to Aug 2020. Methodology: All the patients over the age of 18 years who were on mechanical ventilation in a medical intensive care unit were included in the study. The patients were given spontaneous breathing trials as a protocol for weaning from mechanical ventilation. Lung ultrasound was performed on 4 points of anterior chest wall before and after spontaneous breathing trials. Before and after spontaneous breathing trials counting of B lines was done on ultrasound of lung and comparison of increase in B lines (Delta-B-lines) was done with reference diagnosis of weaning induced pulmonary edema diagnosed by intensivist who was blinded to the results of lung ultrasound. Results: The study included 42 patients including 23 (54.8%) men and 19 (45.2%) women. 14 cases failed spontaneous breathing trials. Seven cases (16.7%) had weaning induced pulmonary edema. Delta-B-lines ≥6 diagnosed weaning induced pulmonary edema with 100% accuracy. Out of the remaining seven patients with weaning failure but without weaning induced pulmonary edema, 6 (28.6%) had Delta-B-lines ≥6. The ultrasound lung technique had a 100% sensitivity profile to detect weaning induced pulmonary edema and a specificity of 77.78%. Conclusion: The study indicates that Delta-B-lines ≥6 diagnosed the weaning induced pulmonary edema with the best accuracy.

scholarly journals Role of Serum B-type Natriuretic Peptide before and after 2hours of Spontaneous Breathing Trial among Patients under Mechanical Ventilation

2021 ◽  
Vol 8 (2) ◽  
pp. 125-129
Author(s):  
AKM Faizul Hoque ◽  
Manas Kanti Mazumder ◽  
Omma Hafsa Any ◽  
Sharna Moin ◽  
Rocky Das Gupta ◽  
...  
Keyword(s):  
Mechanical Ventilation ◽  
Spontaneous Breathing ◽  
Characteristic Curve ◽  
Spontaneous Breathing Trial ◽  
Area Under The Curve ◽  
Before And After ◽  
Mechanical Ventilation Support ◽  
Study Population ◽  
Medical University ◽  
Weaning Outcome

Background: Weaning of a patient from mechanical ventilation is very important for the outcomes of the patients. Objective: The purpose of the study was to evaluate the serum level of BNP before and after 2hours of spontaneous breathing trial (SBT) among patients under mechanical ventilation. Methodology: This prospective cohort study was conducted in the Department of Anesthesia, Analgesia and Intensive Care Medicine at Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh over a period of 2 years. Study population was selected for weaning from mechanical ventilation support for the first time in the age group of more than 18 years with both sexes. Plasma BNP level of all patients was measured before and after 2 hours of spontaneous breathing trial. Results: A total number of 30 patients were recruited for this study. One-third (33.3%) of the patients failed on SBT. The mean percent changes of BNP (pg/ml) during 2-h of SBT in weaning success and failure groups were 38.41±9.379 and 59.51±2.940 respectively (p=0.01). The receiver-operating characteristic curve analysis for BNP as a predictor of weaning outcome, showed that the area under the curve (AUC) was 0.89. Conclusion: In conclusion BNP is currently a good predictor of different cardiac diseases. Journal of Current and Advance Medical Research, July 2021;8(2):125-129

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.

scholarly journals Contribution of Levosimendan in Weaning from Mechanical Ventilation in Patients with Left Ventricular Dysfunction: A Pilot Study

2019 ◽  
Vol 2019 ◽  
pp. 1-8 ◽  
Author(s):  
Ifigeneia Kaltsi ◽  
Epameinondas Angelopoulos ◽  
Georgios Tzanis ◽  
Antonios Sideris ◽  
Konstantinos Tyrovolas ◽  
...  
Keyword(s):  
Mechanical Ventilation ◽  
Spontaneous Breathing Trial ◽  
Left Ventricular ◽  
Arterial Oxygen ◽  
Lv Function ◽  
Mechanically Ventilated ◽  
Mechanically Ventilated Patients ◽  
Lv Dysfunction ◽  
Weaning Failure ◽  
Ventilated Patients

Purpose. Mechanically ventilated patients with left ventricular (LV) dysfunction are at risk of weaning failure. We hypothesized that optimization of cardiovascular function might facilitate the weaning process. Therefore, we investigated the efficacy of levosimendan in difficult-to-wean patients with impaired LV performance. Materials and Methods. Nineteen mechanically ventilated patients, with LV ejection fraction (LVEF) 34 ± 8%, difficult-to-wean from the ventilator, were assessed by transthoracic echocardiography before the start and at the end of a spontaneous breathing trial (SBT) (first SBT). Eight patients successfully weaned. The remaining 11 failed-to-wean patients received a 24-hour infusion of levosimendan, and they were reassessed during a second SBT. Results. After levosimendan administration, LVEF increased from 30 ± 10 to 36 ± 3% (p=0.01). End-SBT peak e′ velocity increased from 7 to 9 cm/s (p=0.02). E/e′ increased from 10.5 to 12.9 during the first SBT, whereas it remained constant at 10 throughout the second SBT (p=0.01). During the second SBT, partial pressure of arterial oxygen and central venous oxygen saturation improved, compared to the first one (93 ± 34 vs. 67 ± 28 mmHg, p=0.03, and 66 ± 11% vs. 57 ± 9%, p=0.02, respectively). Nine of the 11 patients were successfully weaned from the ventilator. Conclusions. In difficult-to-wean from mechanical ventilation patients with LV dysfunction, levosimendan might contribute to successful weaning by improving both systolic and diastolic LV function.

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)

An Integrative Index for Predicting Extubation Outcomes After Successful Completion of a Spontaneous Breathing Trial in an Adult Medical Intensive Care Unit

2017 ◽  
Vol 34 (8) ◽  
pp. 640-645 ◽  
Author(s):  
Tsung-Ju Wu ◽  
Judith Shu-Chu Shiao ◽  
Hsin-Liang Yu ◽  
Ruay-Sheng Lai
Keyword(s):  
Mechanical Ventilation ◽  
Intensive Care ◽  
Serum Albumin ◽  
Spontaneous Breathing ◽  
Characteristic Curve ◽  
Spontaneous Breathing Trial ◽  
Invasive Mechanical Ventilation ◽  
Extubation Failure ◽  
Rapid Shallow Breathing Index ◽  
Medical Intensive Care

Background: Among respiratory predictors, rapid shallow breathing index (RSBI) has been a commonly used respiratory parameter to predict extubation outcomes. However, the outcome of prediction remains inconsistent. Regarding nonrespiratory predictors, serum albumin, hemoglobin, bicarbonate, and patients’ alertness have been reported to be associated with successful weaning or extubation. We aimed to develop an integrative index combining commonly used predictors in the adult medical intensive care units (MICUs) and to compare the predictability of the index with RSBI. Methods: This prospective observational study with retrospective data collection of planned extubations was conducted in a 14-bed adult MICU. We enrolled patients who received mechanical ventilation via an endotracheal tube in the adult MICU for >24 hours and passed a 2-hour spontaneous breathing trial and underwent extubation. Extubation failure was defined as reinstitution of invasive mechanical ventilation within 48 hours of extubation. Respiratory parameters and Glasgow Coma Scale (GCS) scores of patients were recorded prospectively. Nonrespiratory parameters were recorded retrospectively. Logistic regression was used to determine significant predictors of extubation outcomes. Results: Fifty-nine patients comprising 70 extubations were enrolled. Extubation failure was significantly and positively associated with lower serum albumin (albumin < 2.6 g/dL, odds ratio [OR] = 5.1; 95% confidence interval [CI], 1.04-24.66), lower hemoglobin (hemoglobin < 10.0 g/dL, OR = 10.8; 95% CI, 2.00-58.04), and lower GCS scores (GCS score ≤ 8, OR = 6.1; 95% CI = 1.15-32.34). By using an integrative index combining the 3 parameters together, the sensitivity and specificity to predict extubation outcomes were 78.6% and 75.9%, respectively. The area under the receiver operating characteristic curve of the index was significantly higher than RSBI (0.84 vs 0.61, P = .026). Conclusion: The integrative index combining serum albumin, hemoglobin, and GCS scores could predict extubation outcomes better than RSBI in an adult MICU.

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