Predictors Of Weaning Research Articles

N-terminal pro brain natriuretic peptide as a novel predictor of weaning from mechanical ventilation

N-terminal pro brain natriuretic peptide as a novel predictor of weaning from mechanical ventilation

Defining Predictors of RVAD Weaning Post-LVAD Implantation in a Multi-Institutional Retrospective Cohort

<h3>Purpose</h3> Deciding which patients can be weaned from an RVAD placed after LVAD implantation could help triage advanced heart failure device strategy. Therefore, we set out to determine the predictors of RVAD weaning. <h3>Methods</h3> A multi-center retrospective study of 826 consecutive patients who received either a HeartMate2 or HVAD between 1/2007 an 12/2007. We identified 91 patients who received an early RVAD insertion during their LVAD implant index admission. A Cox Proportional hazard model was constructed to identify predictors of RVAD weaning. <h3>Results</h3> There were 91 patients (11%) who required an RVAD after LVAD with 48 (52%) weaned from RVAD support and 43 (48%) not weaned. Patients who were weaned had a lower prevalence of hypertension, higher pre-operative ACE-inhibitor use, and lower pre-operative transpulmonary gradient (TPG), RA-PCWP ratio, and RVSWI; they were also more likely to receive concomitant RVAD at time of LVAD insertion and ultimately transplanted more often (Table 1). Our multivariable model for predictors of RVAD weaning included pre-operative creatinine (HR 0.32 [0.15, 0.70], p = 0.004), PVR (HR 1.23 [1.02, 1.48], p = 0.03), non-white ethnicity (HR 2.56 [1.19, 5.54], p = 0.02), COPD (HR 4.63 [1.32, 16.25], p = 0.02), and concomitant RVAD insertion (HR 2.87 [1.00, 8.21], p-value = 0.05) with a model c-statistic of 0.84. The survival curve demonstrates that patients who are weaned from RVAD have significantly improved 1-year mortality (Figure 1, p < 0.001). <h3>Conclusion</h3> In a multi-institutional continuous-flow LVAD cohort, we show novel predictors of RVAD weaning that can help triage mechanical support strategy.

The predictive value of brain natriuretic peptide or N-terminal pro-brain natriuretic peptide for weaning outcome in mechanical ventilation patients: Evidence from SROC

Objective:Mechanical ventilation is an important treatment for critically ill patients. Physicians generally perform a spontaneous breathing trial (SBT) to determine whether the patients can be weaned from mechanical ventilation, but almost 17% of the patients who pass the SBT still require respiratory support. Cardiac dysfunction is an important cause of weaning failure. The use of brain natriuretic peptide or N-terminal pro-BNP is a simple method to assess cardiac function. We performed a systematic review of investigations of brain natriuretic peptide or N-terminal pro-BNP as predictors of weaning from mechanical ventilation.Data sources:PubMed (1950 to December 2020), Cochrane, and Embase (1974 to December 2020), and some Chinese databases for additional articles (China Biology Medicine (CBM), China Science and Technology Journal Database (CSTJ), and Wanfang Data and China National Knowledge Infrastructure (CNKI)).Study selection:We systematically searched observation studies investigating the predictive value of brain natriuretic peptide or N-terminal pro-brain natriuretic peptide in weaning outcome of patients with mechanical ventilation.Data extraction:Two independent reviewers extracted data. The differences are resolved through consultation.Data synthesis:We included 18 articles with 1416 patients and extracted six index tests with pooled sensitivity and specificity for each index test. For the BNP change rate predicting weaning success, the pooled sensitivity was 89% (83%–94%) and the pooled specificity was 82% (72%–89%) with the highest pooled AUC of 0.9511.Conclusions:The brain natriuretic peptide change rate is a reliable predictor of weaning outcome from mechanical ventilation.

Predicting Parameters for Successful Weaning from Veno-Arterial Extracorporeal Membrane Oxygenation in Cardiogenic Shock.

AimsPercutaneous veno‐arterial extracorporeal membrane oxygenation (VA‐ECMO) is utilized for patients with cardiogenic shock or cardiac arrest. However, the procedure protocol for weaning from VA‐ECMO has not been well established. The present study aimed to determine the usefulness of echocardiographic and pulmonary artery catheter parameters for predicting successful weaning from VA‐ECMO in patients with refractory cardiogenic shock.Methods and resultsWe retrospectively studied 50 patients who were hospitalized and supported by VA‐ECMO for >48 h between January 2013 and March 2017. Patients successfully weaned from VA‐ECMO without reintroduction of VA‐ECMO or left ventricular assist device implantation were defined as 30 day survivors. Echocardiographic and pulmonary artery catheter parameters were evaluated when ECMO flow was limited to a maximum of 1.5–2.0 L/min. Twenty‐four patients were successfully weaned from VA‐ECMO, whereas 26 were not. Fractional shortening, corrected left ventricular ejection time (LVETc, defined as LVET divided by the square root of heart rate), left ventricular outflow tract velocity time integral, and LVETc divided by pulmonary artery wedge pressure (PAWP) were significantly larger in the 30 day survivor groups. Multivariable analysis revealed LVETc∕PAWP as a significant independent predictor of successful weaning (LVETc∕PAWP, odds ratio 0.82, 95% confidence interval 0.71–0.94, P = 0.005). Receiver operating characteristic curve analysis revealed 15.9 as the optimal LVETc∕PAWP for predicting successful weaning (area under the curve 0.82).ConclusionsThe present findings indicate that LVETc∕PAWP is a potential predictor of successful weaning from VA‐ECMO.

Predictors of successful discontinuation from renal replacement therapy during AKI: A meta-analysis.

The predictors of weaning time of renal replacement therapy (RRT) remain controversial for special patients suffering from acute kidney injury (AKI). The present work aims to perform a meta-analysis to evaluate proper predictors of RRT weaning in AKI patients. We systematically searched EMBASE, PubMed, and Cochrane Central Register of Controlled trials for literatures between 1984 and June 2019. Studies evaluating predictors of weaning success of RRT in patients of AKI were included. Random-effects model or fixed-effects model meta-analyses were performed to compute a standard mean difference (SMD). Newcastle-Ottawa Scale was employed to assess the risk of bias. We included 10 observational trials including 1453 patients. Twelve predictors including urine output, serum creatinine, serum urea, mean arterial pressure, central venous pressure, lactate, serum potassium, serum bicarbonate, pH value, SOFA score, urinary urea, and urinary creatinine were identified, showing urine output (p=0.0000), serum creatinine (p=0.008), serum potassium (p=0.02), serum bicarbonate (p=0.01), pH value (p=0.03), urinary urea (p=0.002), and urinary creatinine (p=0.02) were significantly associated with weaning success. With the limited evidence, we speculate that urine output, serum creatinine, serum potassium, serum bicarbonate, pH value, urinary urea, and urinary creatinine might be associated with successful weaning.

Predictors of successful weaning in patients requiring extremely prolonged mechanical ventilation.

For patients on prolonged mechanical ventilation (PMV; > 21 days), successful weaning has been attributed to various factors. The aim of this study is to determine the usefulness of the rapid shallow breathing index(RSBI) and other potential predictors of successful weaning in patients unable to wean and requiring extreme PMV at a hospital-based long-term ventilator facility in Israel. Material and ethods: Retrospective analysis of prospectively collected data over 5 years. A total of 150 subjects on PMV, ready to undergo a weaning process, were included in the study. Of them, 60 (40.0%) were males. The mean age of the whole study population was 76.5 years (SD = 13.6; range 22.0-96.0 years). The subjects were on MV for a mean period of 170.1 days (SD = 237.6; range 25.0-1624.0 days). Sixty patients (40%) were successfully weaned. The mean RSBI in the successfully weaned population was 41.9 breaths/min/L (SD = 12.3; range 13.0-80.4 breaths/min/L), in the population where weaning failed, it was 114.8 breaths/min/L (SD = 69.2; range 47.5-450.0 breaths/min/L). By univariate logistic regression analysis, younger age (p < 0.007), female gender (p < 0.001), decreased duration of MV (p < 0.023), re-spiratory rate (p < 0.001) and RSBI (p < 0.001), increased tidal volume/ideal body weight (p < 0.001) and minute ventilation (p < 0.01) were found to be factors that significantly predict successful weaning. By multivariate analysis, increased tidal volume/ /ideal body weight (p < 0.007) and decreased RSBI (p < 0.046) were found to be independent predictors of successful weaning (p < 0.001; R2 Nagelkerke = 0.90). Factors independently predicting successful weaning in patients requiring extreme PMV included increased tidal volume/ideal body weight and decreased RSBI.

Fluid Balance Predicts Need for Intubation in Subjects With Respiratory Failure Initiated on High-Flow Nasal Cannula.

High-flow nasal cannula (HFNC) has gained widespread use for acute hypoxemic respiratory failure on the basis of recent publications that demonstrated fewer intubations and perhaps lower mortality in certain situations. However, a subset of patients initiated on HFNC for respiratory failure ultimately do require intubation. Our goal was to identify patient-level features predictive of this outcome. This was a retrospective cohort study of subjects with hypoxemic respiratory failure treated with HFNC. Individuals were described as having succeeded (if weaned from HFNC) or failed (if they required intubation). A variety of easily measurable variables were evaluated for their ability to predict intubation risk, analyzed via a multivariate logistic regression model. Of a total of 74 subjects, 42 succeeded and 32 failed. The mean ± SD net fluid balance in the first 24 h after HFNC initiation was significantly lower in the success group versus the failure group (-33 ± 80 mL/h vs 72 ± 117 mL/h; P < .01). An adjusted model found only fluid balance and the previously described respiratory rate (breathing frequency [f]) to oxygenation (ROX) index ([[Formula: see text]/[Formula: see text]]/f) at 12 h as significant predictors of successful weaning (negative fluid balance adjusted odds ratio 0.77 [95% CI 0.62-0.96] for -10 mL/h increments [P = .02]; ROX adjusted OR 1.72 [1.15-2.57], P < .01). A negative fluid balance while on HFNC discriminated well between those who required intubation versus those who were successfully weaned.

Factors Associated With Prolonged Mechanical Ventilation and Reventilation in Acute Cervical Spinal Cord Injury Patients.

Patients who had suffered from acute blunt cervical spinal cord injury (SCI) and admitted our hospital within 24 hours after injury were included in the study. We compared the respiratory function and serum reactive oxidative stress (ROS) after acute cervical SCI, and tried to find out the valuable predictors of weaning in patients with acute cervical SCI. Ventilation impairment is a major complication of acute cervical SCI. Evidence of oxygen radical formation in secondary injury from animal SCI models demonstrates an immediate postinjury increase in ROS production after SCI. We hypothesize that the serum ROS is associated with the severity of patients with acute cervical SCI. Thirty-eight adult patients who had acute cervical SCI and 58 healthy volunteers were enrolled. Respiratory function at admission, at the time of extubation and at 48 hours after extubation, serum oxidative stress, Injury Severity Score and Japanese Orthopaedic Association score at admission were compared. The most notable predictor of mechanical ventilation more than 48 hours was serum thiobarbituric acid-reactive substances (TBARS) level at admission (P = 0.027), and the cut-off value of serum TBARS level was 731.7 μmol/L (sensitivity 87.5% and specificity 78.9%). For the reventilation ≤5 days, the notable predictors were respiratory function at the time of extubation (maximal inspiratory pressure, P = 0.040; maximal expiratory pressure, P = 0.020; and tidal volume, P = 0.036) and serum TBARS level at admission (P = 0.013), the cut-off value of serum TBARS level at admission was 762.3 μmol/L (sensitivity 100% and specificity 90.0%). In this study, respiratory function (maximal inspiratory pressure, maximal expiratory pressure, and tidal volume) at the time of extubation can be useful optimal clinical guidelines for weaning and extubation attempts in patients with acute cervical SCI. Serum TBARS level at admission can be a useful predictor for severity in acute cervical SCI patients. 3.

Electrographic predictors of successful weaning from anaesthetics in refractory status epilepticus.

Intravenous third-line anaesthetic agents are typically titrated in refractory status epilepticus to achieve either seizure suppression or burst suppression on continuous EEG. However, the optimum treatment paradigm is unknown and little data exist to guide the withdrawal of anaesthetics in refractory status epilepticus. Premature withdrawal of anaesthetics risks the recurrence of seizures, whereas the prolonged use of anaesthetics increases the risk of treatment-associated adverse effects. This study sought to measure the accuracy of features of EEG activity during anaesthetic weaning in refractory status epilepticus as predictors of successful weaning from intravenous anaesthetics. We prespecified a successful anaesthetic wean as the discontinuation of intravenous anaesthesia without developing recurrent status epilepticus, and a wean failure as either recurrent status epilepticus or the resumption of anaesthesia for the purpose of treating an EEG pattern concerning for incipient status epilepticus. We evaluated two types of features as predictors of successful weaning: spectral components of the EEG signal, and spatial-correlation-based measures of functional connectivity. The results of these analyses were used to train a classifier to predict wean outcome. Forty-seven consecutive anaesthetic weans (23 successes, 24 failures) were identified from a single-centre cohort of patients admitted with refractory status epilepticus from 2016 to 2019. Spectral components of the EEG revealed no significant differences between successful and unsuccessful weans. Analysis of functional connectivity measures revealed that successful anaesthetic weans were characterized by the emergence of larger, more densely connected, and more highly clustered spatial functional networks, yielding 75.5% (95% confidence interval: 73.1-77.8%) testing accuracy in a bootstrap analysis using a hold-out sample of 20% of data for testing and 74.6% (95% confidence interval 73.2-75.9%) testing accuracy in a secondary external validation cohort, with an area under the curve of 83.3%. Distinct signatures in the spatial networks of functional connectivity emerge during successful anaesthetic liberation in status epilepticus; these findings are absent in patients with anaesthetic wean failure. Identifying features that emerge during successful anaesthetic weaning may allow faster and more successful anaesthetic liberation after refractory status epilepticus.

Predictors of Successful Oxygen Weaning in Older Patients Undergoing Pulmonary Rehabilitation

ObjectivesTo identify clinical and/or functional variables predictive of successful oxygen-weaning among older patients affected by respiratory insufficiency undergoing pulmonary rehabilitation. DesignRetrospective study. Setting and ParticipantsData are from 154 patients aged 65 years and older (mean age = 78.1 years; female 50.6%) admitted to a pulmonary rehabilitation unit to follow an in-patient program. Patients must require oxygen therapy at admission. MethodsAll patients performed the 6-Minute Walking Test at admission and before discharge as well as a spirometry at a steady state. Multivariate logistic regressions were performed to identify positive and negative predictors of successful oxygen weaning. ResultsSuccessful oxygen weaning was obtained in 47 participants (30.5%). The restrictive pattern was associated with a 4-fold likelihood of successful oxygen weaning at the end of the rehabilitation program compared with the obstructive one. A positive association was also found for arterial oxygenation index (PaO2/FiO2 ratio) at baseline. A decreased likelihood of successful oxygen weaning was reported for the subjective dyspnea perception score at exertion evaluated with a modified Borg scale. Conclusions and ImplicationsThe restrictive pattern, PaO2/FiO2 ratio, and modified Borg dyspnea scale score under exertion were significantly associated with successful oxygen-weaning. The identified predictors may support clinicians at precociously identifying patients who may not require oxygen therapy after discharge. Therefore, these findings would make it possible for clinicians to better tailor the rehabilitation program.

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.

Ventilator induced Diaphragmatic Dysfunction assessed by Ultrasonography and its impact on Weaning outcome

Abstract Background Ventilator induced diaphragmatic dysfunction (VIDD), as a loss of diaphragmatic force generating capacity due to the use of mechanical ventilation. Difficulties in discontinuing ventilatory support are encountered in 20–25% of mechanically ventilated patients, with a staggering 40% of time spent in the intensive care unit being devoted to weaning. M-mode ultrasonography is now an accepted qualitative method of assessing diaphragmatic motion in normal and pathological conditions. In this study, we evaluated whether diaphragmatic excursion (DE) as measured by M-mode sonography can be a predictor of weaning and diagnosis of VIDD. Aim The aim of this study is to determine the presence of ventilator induced diaphragmatic dysfunction (VIDD) diagnosed by M-mode ultrasonography and its impact on weaning outcome. Methodology This study was conducted prospectively in critical care unit in Ain Shams Hospital, a university-affiliated, tertiary referral center in Cairo, Egypt. Study subjects included 78 patients between August 2017 to August 2018. who required mechanical ventilation ≥72hrs. who fulfilled the spontaneous breath trial (SBT) criteria, at the start of a 1-hr SBT, each hemidiaphragm was evaluated M-mode sonography with the patient in the supine position. Rapid shallow Breathing index (RSBI) was simultaneously calculated at the bedside. Ultrasonographic Diaphragmatic Dysfunction (DD) was diagnosed if an Diaphragmatic Excursion (DE) was &amp;lt;10 mm or negative, the latter indicating paradoxical diaphragmatic movement. Results Diaphragmatic Dysfunction (DD) among the eligible 78 patients was 48% (n = 37). DD group had longer weaning time [39,2 (26-56) hrs. vs. 22.3 (30-16) hrs. p = 0.001) in DD vs. NDD group respectively and total ventilation time [140 (130-150) hrs. vs. 130 (120–140) hrs. p &amp;gt; 0.05) in DD vs. NDD group respectively. Weaning failure was (45.8% vs. 30.8%, p=0.01) in DD vs. NDD group respectively. In NDD group Rt. DE, mean 25.4 ±4.1 mm. While Lt. side was 25.3±4.6 mm, 11.25mm and 22mm (45-15) respectively. In DD group Rt. DE, mean 7.6 ±2.02mm, IQR 2.4 mm and median 8.2mm (10-1.9). While Lt. side was 9.2±0.8mm, 4.3mm and 8.9mm (9.8-5.7) respectively. The area under the receiver operating characteristics curve (ROC) of ultrasonographic criteria in predicting weaning failure was near similar to that of rapid shallow breathing index. Hypercapenic acidosis in NDD group might protect them from VIDD Conclusions DD is present in a significant percentage 48% (nearly half) of our medical ICU patients on MV ≥ 72 hrs which largely account for weaning failure. DD was associated with a significant longer weaning time, and ICU stay, with no significant difference in 30 day mortality Recommendations DE by US measurements is a valuable tool and is recommended as an adjunctive weaning index to aid prediction of weaning outcome. Evaluating the role of spontaneous ventilation modes and advanced ventilation modes as PAV and NAVA effects on decreas ing VIDD versus controlled modes.

Variables predicting weaning outcome in prolonged mechanically ventilated tracheotomized patients: a retrospective study

BackgroundSeveral studies have assessed predictors of weaning and extubation outcome in short-term mechanically ventilated patients, but there are only few studies on predictors of weaning from prolonged mechanical ventilation.MethodsRetrospective, single-center, observational study at a specialized national weaning center in Germany. Patients’ medical records were reviewed to obtain data on demographics, comorbidities, respiratory indices, and the result of a prospectively documented, standardized spontaneous breathing trial (SBT) upon admission to the weaning center. Respiratory indices assessed were the ventilatory ratio (VR) and parameters derived from calculated mechanical power (MP). Predictors associated with failure of prolonged weaning and failure of the SBT were assessed using a binary logistic regression model.ResultsA total of 263 prolonged mechanically ventilated, tracheotomized patients, treated over a 5-year period were analyzed. After 3 weeks of mechanical ventilation, patients with unsuccessful weaning failed a SBT more frequently and showed significantly increased values for inspiratory positive airway pressure, driving pressure, VR, absolute MP, and MP normalized to predicted body weight and dynamic lung-thorax compliance (LTC-MP). In the logistic regression analyses, variables independently correlated with weaning failure were female gender (adjusted odds ratio 0.532 [95% CI 0.291–0.973]; p = 0.040), obesity (body mass index ≥ 30 kg/m2) (2.595 [1.210–5.562]; p = 0.014), COPD (3.209 [1.563–6.589]; p = 0.002), LTC-MP (3.470 [1.067–11.284]; p = 0.039), PaCO2 on mechanical ventilation (1.101 [95% CI 1.034–1.173]; p = 0.003), and failure of the SBT (4.702 [2.250–9.825]; p < 0.001). In addition, female gender (0.401 [0.216–0.745]; p = 0.004), LTC-MP (3.017 [1.027–8.862]; p = 0.046), and PaCO2 on mechanical ventilation (1.157 [1.083–1.235]; p < 0.001) were independent risk factors for an unsuccessful SBT.ConclusionsIn the present study, the derived predictors of weaning point to a crucial role of the workload imposed on respiratory muscles during spontaneous breathing. Mechanical power normalized to lung-thorax compliance was independently correlated with weaning outcome and may identify patients at high risk for weaning failure.

Determining the optimal time for liberation from renal replacement therapy in critically ill patients: a systematic review and meta-analysis (DOnE RRT)

IntroductionRenal replacement therapy (RRT) is associated with high mortality and costs; however, no clinical guidelines currently provide specific recommendations for clinicians on when and how to stop RRT in recovering patients. Our objective was to systematically review the current evidence for clinical and biochemical parameters that can be used to predict successful discontinuation of RRT.MethodsA systematic review and meta-analysis were performed with a peer-reviewed search strategy combining the themes of renal replacement therapy (IHD, CRRT, SLED), predictors of successful discontinuation or weaning (defined as an extended period of time free from further RRT), and patient outcomes. Major databases were searched and citations were screened using predefined criteria. Studied parameters were reported and, where possible, data was analyzed in the pooled analysis.ResultsOur search yielded 23 studies describing 16 variables for predicting the successful discontinuation of RRT. All studies were observational in nature. None were externally validated. Fourteen studies described conventional biochemical criteria used as surrogates of glomerular filtration rate (serum urea, serum creatinine, creatinine clearance, urine urea excretion, urine creatinine excretion). Thirteen studies described physiologic parameters such as urine output before and after cessation of RRT, and 13 studies reported on newer kidney biomarkers, such as serum cystatin C and serum neutrophil gelatinase-associated lipocalin (NGAL). Six studies reported sensitivity and specificity characteristics of multivariate models. Urine output prior to discontinuation of RRT was the most-studied variable, with nine studies reporting. Pooled analysis found a sensitivity of 66.2% (95% CI, 53.6–76.9%) and specificity of 73.6% (95% CI, 67.5–79.0%) for urine output to predict successful RRT discontinuation. Due to heterogeneity in the thresholds of urine output used across the studies, an optimal threshold value could not be determined.ConclusionsNumerous variables have been described to predict successful discontinuation of RRT; however, available studies are limited by study design, variable heterogeneity, and lack of prospective validation. Urine output prior to discontinuation of RRT was the most commonly described and robust predictor. Further research should focus on the determination and validation of urine output thresholds, and the evaluation of additional clinical and biochemical parameters in multivariate models to enhance predictive accuracy.

Peripheral perfusion index as a predictor of failed weaning from mechanical ventilation.

We hypothesized that impairment of peripheral perfusion index (PPI) during spontaneous breathing trial (SBT) might be predictive of weaning failure. We included 44 consecutive, adult, patients, who were scheduled for weaning after at least 48 h of invasive mechanical ventilation in this prospective observational study. Weaning failure was defined as failed SBT or reintubation within 48 h of extubation. PPI readings were obtained before initiation of the SBT, and every 5 min till the end of the SBT. PPI ratio was calculated at every time point as: PPI value/ baseline PPI. The primary outcome was the accuracy of PPI ratio at the end of the SBT in detecting failed weaning. Forty-three patients were available for the final analysis. Eighteen patients (42%) were considered failed weaning. PPI ratio was higher in patients with successful weaning compared to patients with failed weaning during the last 15 min of the SBT. PPI ratio at the end of SBT was higher in patients with successful weaning compared to patients with failed weaning. PPI ratio at the end of SBT had good predictive ability for weaning failure {area under receiver operating characteristic curve (95% confidence interval): 0.833(0.688–0.929), cutoff value ≤ 1.41}. The change in PPI during SBT is an independent predictor for re-intubation. PPI could be a useful tool for monitoring the patient response to SBT. Patients with successful weaning showed higher augmentation of PPI during the SBT compared to re-intubated patients. Failure of augmenting the PPI by 41% at the end of SBT could predict re-intubation with negative predictive value of 95%. Clinical trial identifier: NCT03974568. https://clinicaltrials.gov/ct2/show/NCT03974568?term=ahmed+hasanin&draw=3&rank=17

The Timed Inspiratory Effort Index as a Weaning Predictor: Analysis of Intra- and Interobserver Reproducibility.

Prolonged ventilatory weaning may expose patients to unnecessary discomfort, increase the risk of complications, and raise the costs of hospital treatment. In this scenario, indexes that reliably predict successful liberation can be helpful. To evaluate the intra- and interobserver reproducibility of the timed inspiratory effort index as a weaning predictor. This prospective observational study included subjects judged as able to start liberation from mechanical ventilation. For the intra-observer analysis, the same investigator performed 2 measurements in each selected patient with an interval of 30 min a rest. For interobserver analysis, 2 measurements were obtained in another sample of subjects, also with an interval of 30 min rest, but each of one performed by a different investigator. The Bland-Altman diagram, the coefficient concordance of kappa, and the Pearson correlation coefficient were used to compare the measurements. The performance of the timed inspiratory effort index was assessed by receiver operating characteristic curves. Values of P < .05 were considered significant. We selected 113 subjects (43 males; mean ± SD age, 77 ± 14 y). Fifty-six (49.6%) achieved successful liberation, and 33 (29%) died in the ICU. The mean ± SD duration of mechanical ventilation was 14.4 ± 6.7 d. The Bland-Altman diagrams that addressed intra- and interobservers agreement showed low variability between measurements. Values of the concordance coefficients of kappa were 0.82 (0.68-0.95) and 0.80 (0.65-0.94), and of the linear correlation coefficients, 0.86 (0.77-0.91) and 0.89 (0.82-0.93) for the intra- and interobservers measurements, respectively. The mean ± SD values for the area under the curve for each pair of the intra- and interobserver measurements were 0.96 ± 0.07 versus 0.94 ± 0.07 (P = .41) and 0.94 ± 0.05 versus 0.90 ± 0.07 (P = .14), respectively. The variability of the measurement of the timed inspiratory effort index by intra- and interobservers showed very high reproducibility, which reinforced the index as a sensible, accurate, and reliable outcome predictor of liberation from mechanical ventilation.

Transitional Percentage of Minute Volume as a Novel Predictor of Weaning from Mechanical Ventilation in Patients with Chronic Respiratory Failure

PurposeSome patients with respiratory failure fail initial weaning attempts and need prolonged mechanical ventilation (MV). Prolonged MV is associated with many complications and consumption of heathcare resources. Objective weaning indices help staffs to identify high-potential patients for weaning from the MV. Traditional weaning indices are not reliable in clinical practice. Transitional percentage of minute volume (TMV%) is a new index of the work of breathing. This study aimed to investigate the utility of TMV% in the prediction of weaning potential. MethodsThis study was prospectively performed including all patients with prolonged MV. Researchers recorded their demographics, TMV%, respiratory parameters, Acute Physiology and Chronic Health Evaluation II score, and laboratory data upon arrival at the respiratory care center. The factors associated with successful weaning were analyzed. ResultsOut of the 120 patients included, 84 (70.0%) were successfully weaned from MV. Traditional weaning indices such as rapid shallow breathing index could not predict the weaning outcome. TMV% was a valuable parameter as patients with a lower TMV%, higher tidal volume, higher hemoglobin, lower blood urea nitrogen, and lower Acute Physiology and Chronic Health Evaluation II scores had a higher rate of successful weaning. TMV%, tidal volume, and HCO3- levels were independent predictors of successful weaning, and the area under the curve was .79 in the logistic regression model. ConclusionTMV% is a novel and effective predictor of successful weaning. Patients with lower TMV% had a higher MV weaning outcome. Once patients with a high potential for successful weaning are identified, they should be aggressively weaned from MV as soon as possible. Clinical Trials Government IdentifierNCT033480.

A study of different predictors of successful weaning off mechanical ventilation in ventilated patients with chronic obstructive pulmonary disease with acute respiratory failure

Background A lot of indices can be used as predictors of weaning off mechanical ventilation, such as rapid shallow breathing index (RSBI), integrative weaning index (IWI), vital capacity (VC), maximal inspiratory pressure (MIP), and respiratory rate (RR). MIP and IWI were considered the most sensitive parameters for prediction of weaning. Objective To compare between the efficacies of some predictors of successful weaning in ventilated patients with chronic obstructive pulmonary disease with acute respiratory failure. Design A total of 30 patients with chronic obstructive pulmonary disease with acute respiratory failure were mechanically ventilated and classified into two groups, with 15 patients each. Clinical and demographic data assessment and routine investigations were done for all patients, and then RSBI and IWI were measured in group I, and also VC and MIP were measured in group II, whereas RR was measured in the two groups. Results Successful cases had significantly short duration of ventilation and high IWI, MIP, and VC, but RSBI was significantly lower in successful cases, whereas RR was significantly high in failed cases. Conclusion MIP and IWI were considered the most sensitive parameters in predicting the outcome of weaning, and prolonged duration on mechanical ventilation was associated with weaning failure.

The role of noninvasive ventilation in avoiding reintubation of weaned patients from mechanical ventilation guided by expiratory and inspiratory muscle strength assessment

Introduction Prolonged unnecessary mechanical ventilation (MV) has a multitude of complications. The main goal after placing a critically ill patient on MV is to define the best time to begin the weaning process. The peak expiratory flow (PEF) and maximum inspiratory pressure (MIP) are measures of inspiratory and expiratory muscle efficiency and can be used as weaning predictors. Noninvasive ventilation (NIV) can be used as a tool to prevent reintubation after weaning of MV.Objective The aim of this study was to determine whether prophylactic NIV would benefit patients with various cough strengths and various level of MIP to decrease the incidence of reintubation.Patients and methods In this prospective observational study, 80 mechanically ventilated patients were enrolled. At the time of their first spontaneous breathing trial, PEF and MIP were measured. Then, patients were randomly assigned to facemask and NIV groups.Results A total of 36 (90%) patients in NIV group were successfully weaned from MV, whereas four (10%) patients failed to be weaned. On the contrary, 29 (72.5%) patients in face mask group were successfully weaned from MV, whereas 11 (27.5%) patients failed to be weaned.Conclusion NIV has an important role to prevent reintubation after weaning of MV. Moreover, MIP and PEF have an excellent accuracy in prediction of NIV success after extubation.

Noninvasive tri-level positive airway pressure ventilation: is it a new challenging mode in management of patients with chronic obstructive pulmonary disease?

Background Chronic obstructive pulmonary disease (COPD) is a serious issue of sickness and rise in global fatality rates. Noninvasive positive pressure ventilation is the first-line therapy in patients with COPD with respiratory fialure (RF). Tri-level positive airway pressure (Tri-PAP) is new challenging mode of noninvasive ventilation (NIV). Objectives To compare between two modes of noninvasive positive pressure ventilation [bi-level positive airway pressure (Bi-PAP) and Tri-PAP] and to spell out outcomes, complication, and predictors of favorable outcome of NIV in patients with COPD with respiratory failure. Patients and methods This prospective comparative study was accomplished on 30 patients with COPD with respiratory failure, who were subjected to NIV (Bi-PAP or Tri-PAP) and standard conventional therapy. Arterial-blood gases (ABGs) (initially, 6 h, and finally) were analyzed. NIV outcomes, complications, and predictors of success were encountered. Results Patients were categorized according to managerial therapeutic NIV into Bi-PAP (n=15) or Tri-PAP (n=15) groups. Initial, 6-h, and final ABGs analyses (pH, PO2, PCO2, HCO3, and O2 sat) and NIV outcomes (successful or failed weaning) were analogous, without considerable variation between both Bi-PAP and Tri-PAP groups. pH showed crucial advancement after 6 h of initiation of Tri-PAP NIV. Terminal ABG interpretation (pH, PaCO2, PaO2, and O2 sat) had better outcomes than initial and 6-h ABG analyses of Tri-PAP NIV group. Irritations and ulcerations of nasal bridge, dry nose or mouth, nasal congestion, hypotension, and PaCO2 increase were the most hazardous events in both Bi-PAP and Tri-PAP NIV groups. Shorter duration of NIV, lower BMI, higher pH, and lower PCO2 (initially, 6 h, and final ABGs) as well as higher O2 saturation (in final ABG) were predictors of successful weaning in NIV (Bi-PAP and Tri-PAP) groups collectively. Conclusion Bi-PAP and Tri-PAP are appropriate mode of NIV in patients with COPD with RF with minimal complication and better outcomes. Tri-PAP had no superiority of utilization than Bi-PAP mode. pH and PCO2 are the powerful predictors of favorable NIV outcomes.