Weaning Failure Group Research Articles

Mean platelet volume is useful for predicting weaning failure: a retrospective, observational study

BackgroundTo evaluate the usefulness of mean platelet volume (MPV), a marker of inflammation and stress, for predicting weaning failure in patients undergoing invasive mechanical ventilation (IMV) compared to traditional inflammation markers.MethodsThe retrospective observational study including patients who received IMV and underwent spontaneous breathing trial (SBT) was conducted in ICU at Beijing Chao-Yang hospital in China from January, 2013 to December, 2019. According to the weaning outcome, MPV, leukocyte count and C-reaction protein(CRP) were compared between weaning failure and weaning success group. Receiver-operating characteristics (ROC) curves and multivariate logistical regression analysis were constructed to analyze the value of these inflammatory markers for predicting weaning failure.ResultsA total of 261 patients were enrolled in the study and 54 patients (20.7%) experienced weaning failure (45 SBT failure and 9 extubation failure after successful SBT). MPV was a better predictor for weaning failure (AUC 0.777;95%CI, 0.722–0.826) than leukocyte count (AUC 0.6;95%CI,0.538–0.66) and CRP (0.627;95%CI,0.565–0.685). The cutoff value of MPV for predicting weaning failure was 11.3 fl with sensitivity 55.56%, specificity 87.92%, and diagnostic accuracy 81.22%. According to multivariate logistic regression analyses, MPV > 11.3 fl was an independent risk factor for predicting weaning failure.ConclusionsMPV could be a more valuable marker for predicting weaning failure. and the patients with MPV > 11.3 fl should be attentively evaluated before weaning since they are at high risk of weaning failure, and it would be auspicable for those patients to undergo a noninvasive ventilation or high-flow nasal cannula oxygen therapy after extubation or even an early tracheostomy.

Ultrasound-assessed diaphragmatic dysfunction as a predictor of weaning outcome in mechanically ventilated patients with sepsis in intensive care unit

BackgroundWeaning from mechanical ventilation is one of the most common challenges in the intensive care unit (ICU). Most of predictive indices of weaning from mechanical ventilation are often inaccurate. This study was performed to assess the accuracy of diaphragmatic ultrasonography for predicting weaning outcome in mechanically ventilated patients with sepsis in ICU.ResultsSixty patients with sepsis in medical ICU were prospectively enrolled. All patients were ventilated in pressure support. Patients underwent a spontaneous breathing trial (SBT) on T-piece when they met all the following criteria: FiO2 < 0.6, PEEP ≤5 cmH2O, PaO2/FiO2 > 200, respiratory rate <30 breaths per minute, absence of fever, alert and cooperative, hemodynamic stability without or with low-dose vasoactive therapy support, and rapid shallow breathing index (RSBI)<105. During the trial, the patient was instructed to perform deep breathing to total lung capacity (TLC) and then exhaling to residual volume (RV) and the diaphragm was visualized in the 8th or 9th intercostal space between anterior and mid-axillary lines using a 3–5-MHz curved ultrasound probe to measure diaphragmatic excursion (DE) and a 7–11-MHz linear ultrasound probe to measure diaphragmatic thickness (DT) at TLC and RV, and the diaphragmatic thickness fraction (DTF) was calculated as percentage from the following formula (thickness at end inspiration—thickness at end expiration)/thickness at end expiration. According to weaning outcome, patients were divided into 2 groups: successful weaning group and weaning failure group. Weaning failure was defined as the inability to maintain spontaneous breathing for at least 48 h, without any form of ventilatory support.In the present study, right DTF of more than 37% and DE during deep breathing of more than 6.1 and 5.4 cm on the Rt and Lt side, respectively, were associated with successful weaning from MV. In the study, the sensitivities for right and left DE and DTF were 58.33, 62.5, and 58.33%, respectively, and the pooled specificities were 83.33, 83.33, and 100%, respectively, with p value = 0.032, 0.028, and 0.001, respectively. The area under curve (AUC) for Rt, Lt DE, and DTF were 0.701, 0.712, and 0.840, respectively. The present data indicate a satisfactory diagnostic accuracy in predicting extubation outcome.ConclusionsUltrasonography-based determination of diaphragm function by assessing DTF and DE can be used as predictor of weaning outcome in mechanically ventilated patients with sepsis.

Biomarkers Associated with Failure of Liberation from Oxygen Therapy in Severe COVID-19: A Pilot Study.

This study aimed to investigate whether clinical and laboratory biomarkers can identify patients with COVID-19 who are less likely to be liberated from oxygen therapy. This was a retrospective study comparing 18 patients in the weaning failure group with 38 patients in the weaning success group. Weaning failure was defined as death or discharge with an oxygen device before day 28 after hospital admission or requiring oxygen support as of day 28. The median quick Sequential Organ Failure Assessment (qSOFA) score was significantly higher and the median SpO2/FiO2 was significantly lower in the weaning failure group. The laboratory biomarkers, procalcitonin (PCT) and D-dimer, were significantly higher in the weaning failure group, as were the biomarkers of endothelial injury, such as angiopoietin-2 (Ang-2) and Ang-2/Ang-1, and tumor necrosis factor-α (TNF-α). Patients’ qSOFA scores, SpO2/FiO2, and PCT, D-dimer, Ang-2, Ang-2/Ang-1, endocan (4-day and 7-day increases), and TNF-α levels predicted weaning failure; 7-day endocan levels were the best predictor of weaning failure with an AUC of 0.81 (95% CI, 0.67–0.94). We identified clinical and laboratory parameters, including plasma biomarkers of endothelial injury, that may be considered as biomarkers for predicting failure of liberation from oxygen therapy in patients with severe COVID-19.

Expert consensus on the use of human serum albumin in critically ill patients.

Expert consensus on the use of human serum albumin in critically ill patients.

Application of bedside ultrasound in predicting the outcome of weaning from mechanical ventilation in elderly patients

BackgroundWith the increased ageing of society, more and more elderly people are admitted to the intensive care unit, How to accurately predict whether elderly patients can successfully wean from the ventilator is more complicated. Diaphragmatic excursion (DE) and diaphragm thickening fraction (DTF) were measured by bedside ultrasound to assess diaphragm function. The lung ultrasound score (LUS) and the rapid shallow breathing index (RBSI) were used as indices of diaphragm function to predict the outcome of weaning from mechanical ventilation. The aim of this study was to examine the clinical utility of these parameters in predicting extubation success.MethodsThis prospective study included 101 consecutive elderly patients undergoing a trial of extubation in the ICU of Haidian Hospital between June 2017 and July 2020. Patients were divided into the successful weaning group (n = 69) and the failed weaning group (n = 32). Baseline characteristics, including RSBI, were recorded. Measurements of DE, DTF and LUS were made using ultrasound within 24 h before extubation.ResultsMedian DE was greater in patients with extubation success than in those with extubation failure (1.64 cm vs. 0.78 cm, p = 0.001). Patients with extubation success had a greater DTF than those with extubation failure (49.48% vs. 27.85%, p = 0.001). The areas under the receiver operating curves for the RSBI, LUS, DE and DFT were 0.680, 0.764, 0.831 and 0.881, respectively. The best cut-off values for predicting successful weaning were DTF ≥ 30%, DE ≥ 1.3 cm, LUS ≤ 11, and RSBI ≤ 102. The specificity of DTF (84%) in predicting weaning outcome was higher than that of RBSI (53%), that of LUS (55%), and that of DE (62%). The sensitivity of DTF (94%) was greater than that of RBSI (85%), that of LUS (71%), and that of DE (65%). The combination of RSBI, LUS, DE, and DTF showed the highest AUC (AUC = 0.919), with a sensitivity of 96% and a specificity of 89%.ConclusionsDTF has higher sensitivity and specificity for the prediction of successful weaning in elderly patients than the other parameters examined. The combination of RSBI, LUS, DE and DFT performed well in predicting weaning outcome. This has potentially important clinical application and merits further evaluation.

Association of baseline diaphragm, rectus femoris and vastus intermedius muscle thickness with weaning from mechanical ventilation

BackgroundTo determine whether baseline diaphragm (Tdi), rectus femoris (RF) and vastus intermedius (VI) muscle thickness (TRF and TRF + VI) are associated with weaning success. Material and methodsRight Tdi, TRF and TRF + VI were measured by ultrasonography within 36 h of intubation and diaphragmatic excursion (DE) was evaluated at the first spontaneous breathing trial in adult critically-ill patients. Reintubation or death within 7 days after extubation was defined as weaning failure. Weaning failure and success groups were compared in terms of ultrasonographic measurements and clinical features. ResultsThirty-eight patients were assessed for weaning, 15 (39.4%) being in the weaning failure group. The median body mass index (BMI) was lower while the median clinical frailty scale (CFS), vasopressor use, duration of mechanical ventilation, intensive care and hospital mortality rate were higher in the weaning failure group, and the median TRF + VI (14.0 [12.3–26.2] vs 23.6 [21.3–27.1] mm, p = 0.03) and median DE (19.4 [14.6–24.0] vs 25.9 [19.3–38.5] mm, p = 0.045) were lower. The median Tdi was similar in two groups (1.9 [1.5–2.3] vs 2.0 [1.7–2.4] mm, p = 0.26). In ROC analysis, area under the curve for TRF + VI was 0.71 (95% CI: 0.51–0.90; p = 0.035), with 21 mm cut-off having sensitivity of 82% and specificity of 57%. Binary logistic regression analysis revealed TRF + VI < 21 mm as the only predictor of weaning failure with an odds ratio of 10.5 (95% CI: 1.1–97.8, p = 0.038) after adjusting for age, sex, BMI and CFS. ConclusionsTRF + VI lower than 21 mm, measured by ultrasonography within 36 h of intubation, was associated with weaning failure among critically-ill patients.

Risk factors for the first ventilator weaning failure in preterm infants receiving invasive mechanical ventilation

OBJECTIVE To study the risk factors for the first ventilator weaning failure and the relationship between the weaning failure and prognosis in preterm infants receiving invasive mechanical ventilation. METHODS A retrospective analysis was performed for the preterm infants who were admitted to the Neonatal Intensive Care Unit of Peking University Third Hospital and received mechanical ventilation within 72 hours after birth. According to whether reintubation was required within 72 hours after the first weaning, the infants were divided into a successful weaning group and a failed weaning group. RESULTS A total of 282 preterm infants were enrolled, and there were 43 infants (15.2%) in the failed weaning group. Compared with the successful weaning group, the failed weaning group had significantly lower gestational age and birth weight (P < 0.05), a significantly higher rate of intubation in the delivery room (P < 0.05), and a significantly higher proportion of infants with patent ductus arteriosus (PDA; diameter ≥ 2.5 mm) (P < 0.05). Use of ≥ 2 vasoactive agents before ventilator weaning (OR=2.48, 95%CI:1.22-5.03, P < 0.05) and PDA (≥ 2.5 mm) (OR=4.54, 95%CI:2.02-10.24, P < 0.05) were risk factors for ventilator weaning failure. Compared with the successful weaning group, the failed weaning group had significantly higher incidence rates of ventilator-associated pneumonia, moderate-to-severe bronchopulmonary dysplasia, and sepsis (P < 0.05). The oxygen inhalation time and hospital stay in the failed weaning group were significantly longer than those in the successful weaning group (P < 0.05). CONCLUSIONS Use of ≥ 2 vasoactive agents before ventilator weaning and PDA (≥ 2.5 mm) are risk factors for ventilator weaning failure, and ventilator weaning failure may be associated with adverse outcomes in hospitalized preterm infants.

Influencing factors of weaning outcome of intensive care unit patients with planned extubation

To determine the risk factors of extubation failure and its effect on the prognosis of patients who had successfully passed a spontaneous breathing trial (SBT). The clinical data of patients with mechanical ventilation more than 24 hours who passed SBT admitted to department of intensive care unit (ICU) of First Hospital of Qinhuangdao from November 2018 to November 2019 were retrospectively analyzed. According to the outcome of weaning within 48 hours after weaning, patients were divided into weaning success group and weaning failure group. The baseline data, the presence of basic cardiopulmonary diseases, B-type natriuretic peptide (BNP), fluid balance, albumin and hemoglobin within 24 hours before weaning, the time of mechanical ventilation before weaning, rapid shallow breathing index (RSBI) during SBT, oxygenation index, cough peak flow at the end of SBT, and prognostic indicators were collected. The outcome of weaning was taken as the dependent variable, and the observation factors were taken as the independent variable for univariate analysis. The factors with statistical significance in univariate analysis were analyzed by binary Logistic regression to determine the influencing factors of weaning failure. Of the 204 patients, 167 (81.9%) were successfully weaned, and 37 (18.1%) failed. Compared with the weaning success group, the total duration of mechanical ventilation and the length of ICU stay in the weaning failure group were significantly longer [days: 13.0 (7.5, 23.5) vs. 5.0 (3.0, 8.0), 17.0 (12.5, 31.0) vs. 10.0 (6.0, 15.0), both P < 0.01], and the tracheotomy rate and mortality were significantly higher (32.4% vs. 0%, 51.4% vs. 0%, both P < 0.01). Univariate analysis showed that there were significant differences in age, proportion of patients with cardiopulmonary diseases, BNP and cough peak flow between weaning failure group and weaning success group [age (years old): 70.65±15.78 vs. 62.69±15.82, cardiopulmonary diseases: 62.2% vs. 24.6%, BNP (ng/L): 416.87 (32.70, 1 225.80) vs. 45.36 (10.00, 273.60), cough peak flow (L/min): 59.89±9.06 vs. 83.84±16.52, all P < 0.01]. However, there were no significant differences in gender, acute physiology and chronic health evaluation II (APACHE II) at admission, mechanical ventilation time before weaning, albumin, hemoglobin, oxygenation index, RSBI and fluid balance 24 hours before weaning between weaning failure group and weaning success group [male: 51.4% vs. 68.3%, APACHE II: 16.70±6.65 vs. 15.67±6.28, mechanical ventilation time before weaning (days): 6.0 (2.5, 11.0) vs. 5.0 (3.0, 8.0), albumin (g/L): 27.78±4.15 vs. 27.76±4.46, hemoglobin (g/L): 102.43±15.80 vs. 100.61±17.19, oxygenation index (mmHg, 1 mmHg = 0.133 kPa): 359.33±79.83 vs. 365.75±78.23, RSBI (times×L-1×min-1): 50.73±24.97 vs. 46.76±15.53, positive fluid balance: 70.3% vs. 69.5%, all P > 0.05]. The results of binary Logistic regression analysis showed that age ≥ 75 years old [odds ratio (OR) = 3.099, 95% confidence interval (95%CI) was 1.003-9.574, P = 0.049], presence of cardiopulmonary diseases (OR = 3.599, 95%CI was 1.126-11.498, P = 0.031), BNP within 24 hours before weaning (OR = 1.002, 95%CI was 1.000-1.003, P = 0.005) were the risk factors of extubation failure, while cough peak flow at the end of SBT was the protective factor (OR = 0.869, 95%CI was 0.823-0.917, P = 0.000). For patients who had successfully passed SBT, age ≥ 75 years old, the presence of cardiopulmonary diseases and an increased level of BNP within 24 hours were the risk factors of extubation failure. In addition, the higher the cough peak flow at the end of SBT, the lower the risk of weaning failure will be.

Clinical outcomes and prognostic factors for prolonged mechanical ventilation in patients with acute stroke and brain trauma

Neurological dysfunction is a common condition necessitating prolonged mechanical ventilation (PMV). We investigated the clinical features and outcomes of patients with acute neurological diseases requiring PMV.This retrospective observational study was conducted at the Respiratory Care Center (RCC) of Chang Gung Memorial Hospital, Taiwan, between January 2011 and January 2014. The main outcome was weaning success, defined as successful withdrawal from mechanical ventilator support for more than 5 days.The study included 103 patients with acute stroke and brain trauma receiving PMV. Weaning success was reported in 63 (61%) patients and weaning failure was reported in 40 (39%) patients. Patients in the weaning failure group were older and had a lower RCC Glasgow Coma Scale (GCS) score (6.0 vs 7.9, p = 0.005), lower albumin level (2.8 vs 3.1, p = 0.015), longer RCC stay (28.7 vs 21.3 days, p = 0.017), and higher in-hospital mortality rate (47% vs 9%, p < 0.01). Multivariate analysis revealed that reduced RCC GCS score is an independent prognostic factor for weaning failure (odds ratio [OR] = 1.22, 95% confidence interval [CI] = 1.05-1.46, p = 0.016) and that per unit increase of RCC GCS score is associated with a lower risk of in-hospital mortality (OR = 0.83, 95% CI = 0.70-0.96, p = 0.019).Reduced RCC GCS score is an independent prognostic factor for weaning failure, and is associated with increased in-hospital mortality rates in patients with acute stroke and brain trauma requiring PMV.

Effect evaluation of bedside ultrasound monitoring of left ventricular functional parameters combined with clinical indicators on veno-arterial extracorporeal membrane oxygenation

To explore the monitoring value of left ventricular functional parameters obtained by bedside ultrasound combined with clinically relevant indicators in patients with veno-arterial extracorporeal membrane oxygenation (VA-ECMO). A retrospective study was conducted. A total of 24 patients receiving VA-ECMO adjuvant support in Renmin Hospital of Wuhan University from June 2018 to January 2020 were selected. The bedside ultrasound was performed on the first day of ECMO support, the day before weaning, the clinical indicators before weaning were obtained. The differences in clinical indicators and the left ventricular functional parameters between the two groups of whether weaning successfully were compared; univariate Logistic regression analysis was used to screen out the related factors affecting weaning. Sixteen patients were successful weaned and 8 patients failed. Compared with the weaning failure group, patients in the weaning success group required less continuous renal replacement therapy (CRRT, cases: 4 vs. 6, P < 0.05), mean arterial pressure (MAP) before weaning was higher [mmHg (1 mmHg = 0.133 kPa): 84.64±9.55 vs. 62.30±8.79, P < 0.05], and the pulse oxygen saturation (SpO2) was also higher (0.966±0.670 vs. 0.866±0.061, P < 0.05), while vasoactive-inotropic score (VIS), serum creatinine (SCr) and serum lactic acid (Lac) were lower [VIS score: 7.27±1.42 vs. 16.93±8.52, SCr (μmol/L): 123.60±83.64 vs. 213.10±117.39, Lac (mmol/L): 1.94±0.91 vs. 5.62±5.48, all P < 0.05]. Univariate Logistic regression analysis showed that the MAP, VIS, SCr, Lac, SpO2 before weaning were the related factors affecting weaning [odds ratio (OR) were 0.306, -0.740, -0.011, -0.632, -4.069; 95% confidence interval (95%CI) were 1.065-1.732, 0.235-0.899, 0.979-0.999, 0.285-0.992 and 0.001-0.208; P values were 0.014, 0.022, 0.038, 0.047, 0.002]. In the weaning success group, left ventricular ejection fraction (LVEF), velocity of mitralannulus in systolic (LatSa), maximum flow velocity of aortic valve (AV-Vmax), velocity-time integral (VTI), left ventricular global longitudinal strain (LVGLS), left ventricular global longitudinal strain rate (LVGLSr) were all increased on the day before ECMO weaning compared with the first day of ECMO support [LVEF: 0.40±0.05 vs. 0.28±0.07, LatSa (cm/s): 6.81±0.91 vs. 4.62±1.02, AV-Vmax (cm/s): 104.81±33.98 vs. 64.44±16.85, VTI (cm): 14.56±3.11 vs. 7.96±1.98, LVGLS: (-8.95±2.59)% vs. (-5.26±1.28)%, LVGLSr (1/s): -0.48±0.11 vs. -0.29±0.09], whereas the ECMO flow was significantly reduced (L/min: 1.46±0.47 vs. 2.64±0.31), the differences were statistically significant (all P < 0.05). There was no significant difference in left ventricular functional parameters between the first day of ECMO support and the day before ECMO weaning in the weaning failure group. Compared with the weaning failure group, the weaning success group had higher LVEF, LatSa, AV-Vmax, VTI, LVGLS, LVGLSr on the day before ECMO weaning [LVEF: 0.40±0.05 vs. 0.26±0.07, LatSa (cm/s): 6.81±0.91 vs. 4.31±1.03, AV-Vmax (cm/s): 104.81±33.98 vs. 67.67±18.46, VTI (cm): 14.56±3.11 vs. 7.75±2.77, LVGLS: (-8.95±2.59)% vs. (-4.81±1.81)%, LVGLSr (1/s): -0.48±0.11 vs. -0.30±0.10, all P < 0.05] and lower ECMO flow (L/min: 1.46±0.47 vs. 2.20±0.62, P < 0.05). Bedside echocardiographic left ventricular function parameters (LVEF, LatSa, AV-Vmax, VTI, LVGLS, LVGLSr) combined with clinical indicators (MAP, VIS, SCr, Lac, SpO2) were helpful to evaluate the therapeutic effect of patients receiving VA-ECMO support and can provide important guiding value in the selection of VA-ECMO weaning timing and the judgment of prognosis.

Echocardiographic Predictors of Successful Extracorporeal Membrane Oxygenation Weaning After Refractory Cardiogenic Shock

Limited data are available regarding echocardiographic predictors for successful weaning from venoarterial (VA) extracorporeal membrane oxygenation (ECMO). We sought to determine whether echocardiographic parameters during ECMO flow study could predict successful weaning from ECMO. A total of 92 ECMO patients from a multicenter ECMO registry underwent VA-ECMO flow study with transthoracic echocardiography before a weaning trial. During VA-ECMO flow study, flow was decreased by 30%-50% of the initial flow for 15minutes, and echocardiography was performed both at baseline and after flow reduction. Changes of echocardiographic parameters were compared between the successful and failed weaning group. Sixty-four of the 92 patients were able to be weaned from VA-ECMO successfully. During VA-ECMO flow study, both lateral e' and tricuspid annular S' velocity improved significantly in the successful weaning group, while such findings were not observed in the failed weaning group. From univariable analysis, left heart decompression, improvement of lateral e' velocity, and improvement of tricuspid annular S' velocity showed significant association with successful VA-ECMO weaning. Predictability of the model with the change of lateral e' and tricuspid annular S' according to the reduction of ECMO flow for successful weaning from VA-ECMO is much higher than that of the model with conventional echocardiographic predictors from previous studies (left ventricular ejection fraction>20%-25%, left ventricular time-velocity integral≥10cm, mitral annulus S'≥6cm/sec). Improvement of lateral e' velocity and tricuspid annular S' velocity during VA-ECMO flow study may better represent cardiac reserve from a recovering heart than conventional echocardiographic parameters at minimal flow. Assessment of tissue Doppler parameters during ECMO flow study is a simple and feasible method to guide physicians on the optimal time to wean from ECMO.

Predictive value of the negative inspiratory force index as a predictor of weaning success: a crosssectional study.

Background Identifying when intubated patients are ready to be extubated remains challenging. The negative inspiratory force (NIF) is a recommended predictor of weaning success. However, little is known about the role of NIF in the weaning process for the Asian surgical intensive population, especially for the Vietnamese population. Here, we aimed to investigate the cutoff threshold and predictive value of the NIF index for predicting the success of ventilator weaning in Vietnamese surgical intensive care patients.Methods A cross-sectional study was conducted at the Surgical Intensive Care Unit of Viet Duc Hospital from October 2016 to August 2017. A total of 64 patients aged 16–70 years undergoing ventilatory support through an orotracheal tube satisfied the criteria for readiness to begin weaning. The correlation between the NIF index with outcomes of the weaning process was analyzed. Specificity (Sp), sensitivity (Se), positive predictive value (PPV), negative predictive value (NPV), receiver operating characteristic (ROC) curve, and area under the curve (AUC) were calculated.Results The success rate of the entire weaning process was 67.2% (43/64). The median NIF values were –26.0 cm H2O (interquartile range [IQR], –28.0 to –25.0) in the successful weaning group and –24.0 cm H2O (IQR, –25.0 to –23.0) in the weaning failure group (P<0.001). According to ROC analysis, an NIF value ≤–25 cm H2O predicted weaning success (AUC, 0.836) with 91% Se, 62% Sp, 83% PPV, and 77% NPV.Conclusions An NIF cutoff threshold ≤–25 cm H2O can be used as predictor of weaning success in Vietnamese surgical intensive care patients.

The predictive value of diaphragm ultrasound for weaning outcomes in surgical intensive care unit

Abstract Introduction: Multiple studies have shown that diaphragmatic ultrasound can better predict the outcome of weaning. The purpose of this study was to investigate the predictive value of two diaphragmatic ultrasound indices, diaphragmatic thickening (DTF) and excursion (DE) for weaning outcomes in the surgical intensive care unit (ICU). Patients and Methods: The study included 60 cases whose mechanical ventilation (MV) time was &gt;48 hours, and all eligibles were divided into either the weaning success group (n=45) or the weaning failure group (n=15). Diaphragm thickness, diaphragmatic excursion (DE), and diaphragmatic thickening fraction (DTF) were measured in the zone of apposition. The rapid shallow breathing index (RSBI) was also recorded. Results: The ventilatory treatment time (p=0,002) and length of ICU stay (p=0,005) in the weaning failure group were longer than the success group. Cut-off values of diaphragmatic measures associated with successful weaning were ≥ 30% for DTF and ≥ 14 mm for DE giving a sensitivity (Se), a specificity (Sp) of 84,4%; 73,3% and 83,3%; 83,3%, respectively. By comparison, RSBI &lt; 80 had a sensitivity of 93,3%, a specificity of 70% for determining weaning success. The areas under the ROC curves for DTF, DE and RSBI were 0,843; 0,807 and 0,873, respectively. Conclusions: Ultrasound evaluation of diaphragmatic excursion (DE) and diaphragmatic thickness fraction (DTF) could be a good predictor of weaning outcome in a surgical intensive unit. It is recommended to consider the use of these parameters with RSBI consequently to improve weaning outcomes. Keywords: Weaning, diaphragm ultrasound, diaphragmatic dysfunction, rapid shallow breathing.

The predictive value of ultrasonic measurement of the diaphragmatic thickening fraction combined with the maximal inspiratory pressure in mechanical ventilation patients

Objective: To evaluate the value of the diaphragmatic thickening fraction (DTF) combined with the maximum inspiratory pressure (MIP) for the prediction of weaning success in mechanically ventilated patients. Methods: Patients admitted to the intensive care unit (ICU) of Yijishan Hospital of Wannan Medical College and on mechanical ventilation for 24 hours from June 2018 to April 2019 were selected as the study subjects. A low-level pressure support ventilation (PSV) method was applied to conduct a spontaneous breathing test (SBT) for 30 minutes after the patients met the screening conditions for clinical weaning; and the patients were weaned when they met the clinical weaning criteria. Before weaning, the patient's MIP was measured. The right hemidiaphragmatic excursion (DE) and the thickness of the diaphragm at the end of inspiration and at the end of exhalation were measured by ultrasound, and the DTF was calculated. The statistical relationship between the DTF, DE and MIP was analyzed. The predictive value for the success of weaning was calculated with the DTF, DE and MIP and was evaluated by the area under the receiver operating characteristic curve (AUC). Results: A total of 73 patients were included in this study, including 57 patients who were successfully weaned, and 16 patients who experienced failure. The DTF of the successful weaning group (35%, 8%) was significantly higher than that of the failed weaning group (25%±5%), and the difference was statistically significant (t=6.401, P<0.01). The MIP (34±9 cmH(2)O) in the successful weaning group was significantly higher than that in the failed weaning group (23±3 cmH(2)O), and the difference was statistically significant (t=7.186, P<0.01). The ROCs for the DTF, MIP, and diaphragmatic displacement were 0.907, 0.896, and 0.749, respectively. A DTF ≥ 27.78%, with a sensitivity of 92.98%, a specificity of 81.25%, and an AUC of 0.907 (95% CI: 0.816-0.963), was used as the standard to predict the success of weaning. An MIP>26.5 cmH(2)O, with a sensitivity of 80.7%, a specificity of 93.75%, and an AUC of 0.896 (95% CI: 0.803-0.955), was used as the standard to predict the success of weaning. The AUC of DTF ≥ 27.78% and MIP ≥ 26.5 cmH(2)O was 0.920 (95% CI:0.832-0.971), and the specificity increased to 87.7%, but the sensitivity was slightly reduced to 87.5%. Conclusions: The DTF and MIP play a crucial role in determining the appropriate time and predicting the outcome of weaning of mechanical ventilation patients. Compared with the DTF and MIP alone, the DTF combined with MIP greatly improved the accuracy of predicting successful weaning.

Value of Combination of Heart, Lung, and Diaphragm Ultrasound in Predicting Weaning Outcome of Mechanical Ventilation.

BackgroundPostextubation distress is detrimental to the prognosis of critically ill patients with successful spontaneous breathing trial. The known risk factors of failed weaning are associated with the heart, lungs, and diaphragm. The aim of this study was to explore the role of a combined model including indicators of heart, lung, and diaphragm ultrasound in predicting the weaning outcome.Material/MethodsPatients’ clinical data and ultrasonic features of heart, lungs, and diaphragm were recorded. Patients were included in either the failed weaning group (n=24) or the successful weaning group (n=81). The association of potential variables with the risk of weaning failure was determined using multivariate logistic regression analysis. The accuracy of potential indicators for predicting the weaning outcome were evaluated and a multiindicator combined model was established to improve the predictive accuracy.ResultsBrain natriuretic peptide (odds ratio [OR]=1.120, P=0.004), left-atrial pressure (LAP) (OR=1.333, P=0.005), lung ultrasound score (LUS) (OR=1.736, P=0.001), and hemidiaphragm dysfunction (OR=3.942, P=0.014) were associated with an increased risk of weaning failure. However, all of these indicators could not accurately predict the weaning outcome independently (all areas under the curve [AUCs] <0.9). The combination of LAP, LUS, and hemidiaphragm dysfunction showed the highest AUC (AUC=0.919).ConclusionsThe combined model including LAP, LUS, and hemidiaphragm dysfunction were the most accurate method for the prediction.

Thoracic fluid content: a novel parameter for predicting failed weaning from mechanical ventilation

BackgroundWeaning of patients from the mechanical ventilation remains one of the critical decisions in intensive care unit. This study aimed to evaluate the accuracy of thoracic fluid content (TFC) as a predictor of weaning outcome.MethodsAn observational cohort study included 64 critically ill surgical patients who were eligible for extubation. Before initiating the spontaneous breathing trial, the TFC was measured using the electrical cardiometry technology. Patients were followed up after extubation and divided into successful weaning group and failed weaning group. Both groups were compared according to respiratory and cardiovascular parameters. Receiver operating characteristic (ROC) curves were constructed to evaluate the ability of TFC to predict weaning outcome.ResultsThe number of successfully weaned patients was 41/64 (64%). Twenty (31%) patients had impaired cardiac contractility, and of them, 13/20 (64%) patients were successfully extubated. Both groups, successful weaning group and failed weaning group, were comparable in most of baseline characteristics; however, the TFC was significantly higher in the failed weaning group compared to the successful weaning group. The area under the ROC curves (AUCs) showed moderate predictive ability for the TFC in predicting weaning failure (AUC [95% confidence interval] 0.69 [0.57–0.8], cutoff value > 50 kΩ−1), while the predictive ability of TFC was excellent in the subgroup of patients with ejection fraction < 40% (AUC [95% confidence interval 0.93 [0.72–1], cutoff value > 50 kΩ−1).ConclusionsThoracic fluid content showed moderate ability for predicting weaning outcome in surgical critically ill patients. However, in the subgroup of patients with ejection fraction less than 40%, TFC above 50 kΩ−1 has an excellent ability to predict weaning failure.

Preliminary establishment of weaning prediction model

To establish a model that can predict weaning failure from ventilation through hemodynamic and fluid balance parameters. A retrospective analysis was conducted. The patients who underwent invasive mechanical ventilation for more than 24 hours and having spontaneous breathing test admitted to intensive care unit (ICU) of Tianjin Third Central Hospital from January 1st, 2017 to December 31st, 2018 were enrolled. The information was collected, which included the baseline data, hemodynamic parameters by pulse indicator continuous cardiac output (PiCCO) monitoring, B-type natriuretic peptide (BNP), urinary output, fluid balance in first 24 hours when patients admitted to ICU, and hemodynamic parameters by PiCCO monitoring, BNP, urinary output, fluid balance, diuretic usage, noradrenalin usage within 24 hours before weaning as well as usage of continuous renal replacement therapy (CRRT) during mechanical ventilation. According to weaning success or failure, the patients were divided into weaning success group and weaning failure group, and the statistical differences between the two groups were calculated. Variables with statistical significance within 24 hours before weaning were included in the multivariate Logistic regression analysis to establish weaning failure prediction model and find out the possible risk factors of weaning failure. A total of 159 patients were included in this study, which included 138 patients in the weaning success group and 21 patients in the weaning failure group. There were no statistical differences in all hemodynamic parameters by PiCCO monitoring, BNP, urinary output, fluid balance within 24 hours into ICU between two groups. There were statistical differences in BNP (χ2 = 9.262, P = 0.026), central venous pressure (CVP; χ2 = 7.948, P = 0.047), maximum rate of the increase in pressure (dPmx; χ2 = 10.486, P = 0.015), urinary output (χ2 = 8.921, P = 0.030), fluid balance (χ2 = 9.172, P = 0.027) within 24 hours before weaning between two groups. In addition, variable about cardiac index (CI; χ2 = 7.789, P = 0.051) was included into multivariate Logistic regression model to improve the prediction model and enhance the accuracy of model. Finally, variables included in the multivariate Logistic regression model were BNP, CVP, CI, dPmx, urinary output, fluid balance volume, and the accuracy of the weaning failure prediction model was 92.9%, the sensitivity was 100%, and the specificity was 76.8%. When the model was adjusted by variables of age and noradrenalin usage, the accuracy of model to predict failure of weaning was 94.2%, the sensitivity was 100%, the specificity was 81.2%. Weaning failure prediction model based on hemodynamic parameters by PiCCO monitoring and variables about liquid balance has high accuracy and can guide clinical weaning.

Predictive value of diaphragmatic rapid shallow breathing index in mechanical ventilation weaning: a systematic review and meta-analysis

Background: Mechanical ventilation weaning is a multifactorial process. D-RSBI cannot only reflect the respiratory function but also the diaphragmatic function with the bedside ultrasound technique. Objective: This review aimed to assess the predictive value of diaphragmatic rapid shallow breathing index (D-RSBI) of weaning outcome. Method: Databases were systematically reviewed including PubMed, Cochrane Library, Embase, CNKI and WanFang Data. Sensitivity and specificity were pooled with random effects models. Results: Nine studies met the inclusion criteria and 568 patients were involved. D-RSBI had a pooled sensitivity of 0.84 and a pooled specificity of 0.87 which predicted weaning success. D-RSBI in the success group was significantly lower than the weaning failure group. Conclusion: D-RSBI is a sensitive and specific predictor for weaning outcomes in spite of the limitations and heterogeneity among the studies. Further studies focusing on particular disease are needed as well.

The predictive value of diaphragm ultrasound for weaning outcomes in critically ill children

IntroductionMultiple studies have shown that diaphragmatic ultrasound can better predict the outcome of weaning in adults. However, there are few studies focusing on children, leading to a lack of sufficient clinical evidence for the application of diaphragmatic ultrasound in children. The purpose of this study was to investigate the predictive value of diaphragm ultrasound for weaning outcomes in critically ill children.MethodsThe study included 50 cases whose mechanical ventilation (MV) time was > 48 h, and all eligibles were divided into either the weaning success group (n = 39) or the weaning failure group (n = 11). Diaphragm thickness, diaphragmatic excursion (DE), and diaphragmatic thickening fraction (DTF) were measured in the zone of apposition. The maximum inspiratory pressure (PImax) was also recorded.ResultsThe ventilatory treatment time (P = 0.002) and length of PICU stay (P = 0.013) in the weaning failure group was longer than the success group. Cut-off values of diaphragmatic measures associated with successful weaning were ≥ 21% for DTF with a sensitivity of 0.82 and a specificity of 0.81, whereas it was ≥0.86 cm H2O/kg for PImax with a sensitivity of 0.51 and a specificity of 0.82. The linear correlation analysis showed that DTF had a significant positive correlation with PImax in children (P = 0.003).ConclusionsDiaphragm ultrasound has potential value in predicting the weaning outcome of critically ill children. DTF and PImax presented better performance than other diaphragmatic parameters. However, DE has limited value in predicting weaning outcomes of children with MV.Trial registrationCurrent Controlled Trials ChiCTR1800020196, (Dec 2018).

Sonographic measurement of lung aeration versus rapid shallow breathing index as a predictor of successful weaning from mechanical ventilation

BackgroundLung ultrasonography is a beneficial tool for evaluation of the extent of lung aeration through measurement of the amount of extravascular lung water. Lung ultrasonography offers some advantages over other methods of assessment of lung aeration including the lack of ionizing radiation and the possibility of use at patient’s bedside. It facilitates dynamic assessment of the lung during mechanical ventilation and during weaning.AimTo assess lung aeration by lung ultrasonography in patients ready for weaning and to validate the significance of its use as a predictor of weaning outcome in comparison with rapid shallow breathing index.Patients and methodsA prospective observational study was conducted on 30 critically ill mechanically ventilated patients for 48 h or more, and ready to undergo spontaneous breathing trial (SBT), according to the readiness criteria. It was conducted in Beni-Suef University Hospital from October 2017 to May 2018. Rapid shallow breathing index was measured before initiation of SBT, and lung ultrasound was done, before, during, and after SBT [lung ultrasound score (LUS) 1, 2, and 3] and were used as predictors for SBT outcome. Patients were divided, according to outcome, into successful weaning group (group A) and failed weaning group (group B).ResultsIn the failed weaning group, LUS1, LUS2, and LUS3 were significantly higher than those of the successful weaning group. At cutoff value of 8.5, LUS3 could be used for prediction of weaning failure with sensitivity 85% and specificity 100%. Moreover, there was a statistically significant relation between LUS and the other variables including hospital stay, mechanical ventilation duration, and mortality.ConclusionLung ultrasound is useful as a bedside tool that can help physicians in their weaning decisions.