Ultrasound-Guided Preload Indices during Different Weaning Protocols of Mechanically Ventilated Patients and its Impact on Weaning Induced Cardiac Dysfunction

BACKGROUND: Elevation of the left ventricular (LV) filling pressure can occur during weaning of mechanical ventilation due to increase in LV preload and/or changes in LV compliance and LV afterload. AIM: The aim of the study was to evaluate respiratory changes in internal jugular vein and inferior vena cava during weaning from mechanical ventilation. METHODS: Prospective observational study conducted on 80 consecutive patients. Patients were divided randomly into two groups who met the readiness criteria to start spontaneous breathing trial (SBT) either on pressure support ventilation (PS/CPAP) for 30 min or T-piece for 120 min. Weaning failure was defined as a failed SBT or reintubation within 48 h. Echocardiographic evaluation was done on assisted controlled ventilation and at the end of SBT for preload assessment. RESULTS: Mitral Septal E/E’ Cutoff value ≥6.1 with sensitivity 81% and specificity 84.2%, and AUC 0.73 for predicting weaning failure. IVC distensibility index on CPAP cutoff value ≥66.5% with sensitivity 100% and specificity 68.4%, and AUC 0.85. In Group II, Mitral Septal E/E’ Cut off value ≥5.8 with sensitivity 83% and specificity 90.9%, AUC 0.83, IVC collapsibility index Cut off value ≥45.5% with sensitivity 72% and specificity 86%, AUC 0.73. CONCLUSION: Mitral Septal E/E’ could predict weaning-induced diastolic dysfunction. IVC plays an important role in predicting weaning failure.

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

Critical Care Research and Practice ◽

10.1155/2019/7169492 ◽

2019 ◽

Vol 2019 ◽

pp. 1-8 ◽

Cited By ~ 1

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.

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Product of driving pressure and respiratory rate for predicting weaning outcomes

Journal of International Medical Research ◽

10.1177/03000605211010045 ◽

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

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Predictors of post-extubation stridor in patients on mechanical ventilation: a prospective observational study

Scientific Reports ◽

10.1038/s41598-021-99501-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Aiko Tanaka ◽

Akinori Uchiyama ◽

Yu Horiguchi ◽

Ryota Higeno ◽

Ryota Sakaguchi ◽

...

Keyword(s):

Mechanical Ventilation ◽

Observational Study ◽

Critically Ill ◽

Critically Ill Patients ◽

Prospective Observational Study ◽

Spontaneous Breathing Trial ◽

Leak Test ◽

Endotracheal Suctioning ◽

Cuff Leak ◽

The Impact

AbstractThe cuff leak test (CLT) has been widely accepted as a simple and noninvasive method for predicting post-extubation stridor (PES). However, its accuracy and clinical impact remain uncertain. We aimed to evaluate the reliability of CLT and to assess the impact of pre-extubation variables on the incidence of PES. A prospective observational study was performed on adult critically ill patients who required mechanical ventilation for more than 24 h. Patients were extubated after the successful spontaneous breathing trial, and CLT was conducted before extubation. Of the 191 patients studied, 26 (13.6%) were deemed positive through CLT. PES developed in 19 patients (9.9%) and resulted in a higher reintubation rate (8.1% vs. 52.6%, p < 0.001) and longer intensive care unit stay (8 [4.5–14] vs. 12 [8–30.5] days, p = 0.01) than patients without PES. The incidence of PES and post-extubation outcomes were similar in patients with both positive and negative CLT results. Compared with patients without PES, patients with PES had longer durations of endotracheal intubation and required endotracheal suctioning more frequently during the 24-h period prior to extubation. After adjusting for confounding factors, frequent endotracheal suctioning more than 15 times per day was associated with an adjusted odds ratio of 2.97 (95% confidence interval, 1.01–8.77) for PES. In conclusion, frequent endotracheal suctioning before extubation was a significant PES predictor in critically ill patients. Further investigations of its impact on the incidence of PES and patient outcomes are warranted.

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Changes in Arterial Pressure during Mechanical Ventilation

Anesthesiology ◽

10.1097/00000542-200508000-00026 ◽

2005 ◽

Vol 103 (2) ◽

pp. 419-428 ◽

Cited By ~ 437

Author(s):

Frédéric Michard

Keyword(s):

Mechanical Ventilation ◽

Blood Flow ◽

Arterial Pressure ◽

Vena Cava ◽

Cardiac Preload ◽

Physical Sign ◽

Aortic Blood Flow ◽

Mechanically Ventilated ◽

Aortic Blood ◽

Cyclic Changes

Mechanical ventilation induces cyclic changes in vena cava blood flow, pulmonary artery blood flow, and aortic blood flow. At the bedside, respiratory changes in aortic blood flow are reflected by "swings" in blood pressure whose magnitude is highly dependent on volume status. During the past few years, many studies have demonstrated that arterial pressure variation is neither an indicator of blood volume nor a marker of cardiac preload but a predictor of fluid responsiveness. That is, these studies have demonstrated the value of this physical sign in answering one of the most common clinical questions, Can we use fluid to improve hemodynamics?, while static indicators of cardiac preload (cardiac filling pressures but also cardiac dimensions) are frequently unable to correctly answer this crucial question. The reliable analysis of respiratory changes in arterial pressure is possible in most patients undergoing surgery and in critically ill patients who are sedated and mechanically ventilated with conventional tidal volumes.

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Use of the product of driving pressure and respiratory rate for predicting failure of weaning from mechanical ventilator in medical patients

10.21203/rs.2.24506/v1 ◽

2020 ◽

Author(s):

Ju Gong ◽

Bibo Zhang ◽

Xiaowen Huang ◽

Bin Li ◽

Jian Huang

Keyword(s):

Mechanical Ventilation ◽

Respiratory Rate ◽

Spontaneous Breathing Trial ◽

Plateau Pressure ◽

Driving Pressure ◽

Medical Patients ◽

Failure Group ◽

Weaning Failure ◽

Weaning Outcome

Abstract Background : Respiratory workload increment in the process of mechanical ventilation withdrawal is critical for the determination of weaning outcome. Pressure, tidal volume (Vt) and respiratory rate (RR ) are considered as patient’s respiratory power, albeit being affected by excessive respiratory load. We aimed to evaluate the performance of driving pressure (DP)×RR to predict the outcome of weaning. Methods : Plateau pressure (Pplat) and positive end-expiratory pressure tot (PEEPtot) were measured during mechanical ventilation, viz., (1) brief deep sedation, (2) on volume support ventilation of MV with Vt 6 ml/kg and a PEEP of 0 cm H 2 O, (3) Pplat and PEEPtot were measured by holding breath for 2s after inhalation and exhalation, respectively. The DP was determined as Pplat minus PEEPtot. The highest RR was recorded within 3 min during spontaneous-breathing trial (SBT). Patients that were able to tolerate SBT for 1 h were directly extubated. These measurements correlated well with weaning outcome. Notably, patients in the “failure” group failed the SBT, died, while others required reintubation or noninvasive ventilation within 48 h of extubation. Results : Out of the 61 patients studied, 22 failed weaning. During the withdrawal of ventilation, DP×RR was 134.2±33.2 cmH 2 O ·breaths/min and 238.5±61.7 cmH 2 O·breaths/min ( P =0.00), DP was 7.9±1.6 cmH 2 O and 9.7±2.3 cmH 2 O ( P =0.00), in the “success” and “failure” groups, respectively. The DP×RR index greater than 170 cmH 2 O·breaths/min had a sensitivity of 95.5% and a specificity of 89.7%, while DP index greater than 8.1 cmH 2 O had 81.8% sensitivity and 64.1% specificity to predict weaning failure. Conclusions : Measurement of DP×RR during withdrawal of ventilation may help predict weaning outcome. Noticeably, high DP×RR increased the likelihood of weaning failure.

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Focused ultrasound of the caudal vena cava in dogs with cavitary effusions or congestive heart failure: A prospective, observational study

PLoS ONE ◽

10.1371/journal.pone.0252544 ◽

2021 ◽

Vol 16 (5) ◽

pp. e0252544

Author(s):

Yen-Yu Chou ◽

Jessica L. Ward ◽

Lara Z. Barron ◽

Shane D. Murphy ◽

Melissa A. Tropf ◽

...

Keyword(s):

Prospective Observational Study ◽

Focused Ultrasound ◽

Inferior Vena ◽

Vena Cava ◽

Study Groups ◽

Minimal Size ◽

Operating Characteristics ◽

Right Heart ◽

Collapsibility Index ◽

Aortic Dimension

Introduction Ultrasonographic indices of the inferior vena cava are useful for predicting right heart filling pressures in people. Objectives To determine whether ultrasonographic indices of caudal vena cava (CVC) differ between dogs with right-sided CHF (R-CHF), left-sided CHF (L-CHF), and noncardiac causes of cavitary effusion (NC). Materials and methods 113 dogs diagnosed with R-CHF (n = 51), L-CHF (30), or NC effusion (32) were enrolled. Seventeen of the R-CHF dogs had pericardial effusion and tamponade. Focused ultrasound was performed prospectively to obtain 2-dimensional and M-mode subxiphoid measures of CVC maximal and minimal size (CVCmax and CVCmin), CVCmax indexed to aortic dimension (CVC:Ao), and CVC collapsibility index (CVC-CI). Variables were compared between study groups using Kruskal-Wallis and Dunn’s-Bonferroni testing, and receiver operating characteristics curves were used to assess sensitivity and specificity. Results All sonographic CVC indices were significantly different between R-CHF and NC dogs (P < 0.001). Variables demonstrating the highest diagnostic accuracy for discriminating R-CHF versus NC were CVC-CI <33% in 2D (91% sensitive and 96% specific) and presence of hepatic venous distension (84% sensitive and 90% specific). L-CHF dogs had higher CVC:Ao and lower CVC-CI compared to NC dogs (P = 0.016 and P = 0.043 in 2D, respectively) but increased CVC-CI compared to the R-CHF group (P < 0.001). Conclusions Ultrasonographic indices of CVC size and collapsibility differed between dogs with R-CHF compared to NC causes of cavitary effusions. Dogs with L-CHF have CVC measurements intermediate between R-CHF and NC dogs.

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Point-of-Care Respiratory Muscle Ultrasound in a Child with Medical Complexity

10.22541/au.163251751.13767591/v1 ◽

2021 ◽

Author(s):

Sigmund Kharasch ◽

LAUREN SELAME ◽

Helene Dumas ◽

Hamid Shokoohi ◽

Andrew Liteplo ◽

...

Keyword(s):

Mechanical Ventilation ◽

Adverse Effects ◽

Point Of Care ◽

Spontaneous Breathing Trial ◽

Point Of Care Ultrasound ◽

Lateral Abdominal Wall ◽

High Resource ◽

Weaning Failure ◽

Medical Complexity ◽

Expiratory Muscles

Point-of-care ultrasound of the diaphragm is a simple, noninvasive, dynamic bedside evaluation of diaphragm function that involves no ionizing radiation, does not require patient transport, and enables the serial evaluation of diaphragmatic function over time. Adverse effects on the diaphragm attributed to ventilator-induced diaphragm dysfunction include longer weaning times, ventilation time and weaning failure. Recent investigations of point-of-care ultrasound evaluating the expiratory muscles of the lateral abdominal wall have found similar adverse effects of mechanical ventilation on these important respiratory muscles resulting in weaning difficulty as well as impaired airway clearance. Children with medical complexity have significant chronic health conditions that may involve multisystem disease (congenital or acquired), high medical fragility, functional and psychosocial impairment, technology dependence (tracheostomies, mechanical ventilation, feeding tubes) and high resource utilization (frequent and/or prolonged hospitalizations). Weaning children dependent on mechanical ventilation is a common rehabilitation goal that has beneficial effects on the quality of life, ease of care, and functionality for transitioning to home care. We present a case of weaning difficulty in a child with medical complexity and the important role of point-of-care ultrasound in the evaluation of the diaphragm and expiratory muscles during a spontaneous breathing trial.

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

Scientific Reports ◽

10.1038/s41598-021-03960-y ◽

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.

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

Journal of Intensive Care ◽

10.1186/s40560-019-0409-x ◽

2019 ◽

Vol 7 (1) ◽

Cited By ~ 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.

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