Spontaneous Breathing Trial Research Articles

The diaphragmatic electrical activity during spontaneous breathing trial in patients with mechanical ventilation: physiological description and potential clinical utility

BackgroundsIncreased respiratory drive has been demonstrated to correlate with weaning failure, which could be quantified by electrical activity of the diaphragm (EAdi). We described the physiological process of EAdi-based parameters during the spontaneous breathing trial (SBT) and evaluated the change of EAdi-based parameters as potential predictors of weaning failure.MethodsWe conducted a prospective study in 35 mechanically ventilated patients who underwent a 2-hour SBT. EAdi and ventilatory parameters were continuously measured during the SBT. Diaphragm ultrasound was performed before the SBT and at the 30 min of the SBT. Three EAdi-based parameters were calculated: neuro-ventilatory efficiency, neuro-excursion efficiency and neuro-discharge per min.ResultsOf the thirty 35 patients studied, 25 patients were defined as SBT success, including 22 patients weaning successfully and 3 patients reintubated. Before the SBT, neuro-excursion efficiency differed significantly between two groups and had the highest predictive value for SBT failure (AUROC 0.875, p < 0.01). Early increases in EAdi were observed in SBT, which are more prominent in SBT failure group. One minute, changes in EAdi and neuro-discharge per min also predicted weaning outcome (AUROCs 0.944 and 0.918, respectively).ConclusionsEAdi-based parameters, especially neuro-excursion efficiency and changes in neuro-discharge per min, may detect impending weaning failure earlier than conventional indices. EAdi monitoring provides physiological insights and a more tailored approach to facilitate successful weaning. Further research should validate these findings and explore the utility of combined EAdi and diaphragm ultrasound assessment in weaning ICU patients from mechanical ventilation.Trial RegistrationRegistered at ClinicalTrials.gov on 20 September 2022 (Identifier: NCT05632822).

Improving Spontaneous Breathing Trials With a Respiratory Therapist-Driven Protocol

RationaleRespiratory therapist (RT) driven spontaneous breathing trial (SBT) protocols have been shown to improve patient outcomes. ObjectiveThis quality improvement (QI) project aimed to standardize and re-establish a RT-driven protocol for screening patients for SBT readiness and placing appropriate patients on SBT. MethodsEndotracheally intubated, mechanically ventilated, adult patients admitted to an academic medical center intensive care unit were screened daily by RTs for SBT readiness. Eligible patients received a SBT with extubation decisions made by the physician team. Patient demographics, indications for intubation, SBT eligibility and exclusionary indications, SBT ventilator settings, start times, duration, and outcomes were collected from the electronic health record. QI interventions included staff re-education, documentation tips, creation of process maps, and interdisciplinary open forum discussions. Results128 patients representing 759 safety screen weaning assessment opportunities were included over a baseline sample and three Plan-Do-Study-Act (PDSA) cycles. Documentation of SBT eligibility increased from 25% at baseline to 86% in PDSA cycle 3 (P=<0.001). Patients assessed to be eligible and received a SBT was 42% in baseline, 35% in PDSA cycle 1, 36% in PDSA cycle 2, and 51% in PDSA cycle 3 (P=0.092). Use of the protocolized SBT ventilator settings improved significantly from 18% to 83% (P=<0.001). Patients who started a SBT before 9 am increased from 41% to 67% (P=0.097) and the median duration of SBT decreased from 211 to 64 minutes. (P=0.008). ConclusionsStandardization of a RT-driven SBT protocol is feasible despite multiple obstacles including staffing and communication challenges and poor shared understanding of terminology.

Effect of Reintubation Within 48 Hours on Mortality in Critically Ill Patients After Planned Extubation.

Re-intubation is necessary in 2% to 30% of cases of patients receiving a planned extubation. This procedure is associated with prolonged mechanical ventilation, a greater need for tracheostomy, a higher incidence of ventilator-associated pneumonia, and higher mortality. The aim of this study was to evaluate the effect of re-intubation within 48 h on mortality after planned extubation by using a randomized controlled trial database. Secondary analysis of a multi-center randomized trial, which evaluated the effect of reconnection to mechanical ventilation for 1 h after a successful spontaneous breathing trial, followed by extubation. The study included adult subjects who received invasive mechanical ventilation for > 12 h. The subjects were divided into an extubation failure group and an extubation success group. The outcome was in-hospital mortality. Two multivariate logistic regression models were constructed to identify independent factors associated with mortality. Among the 336 subjects studied, extubation failed in 52 (15.4%) and they were re-intubated within 48 h. Most re-intubations occurred between 12 and 24 h after planned extubation (median [interquartile range] 16 [6-36] h). Mortality of the extubation failure group was higher both in the ICU (32.6% vs 6.6%; odds ratio [OR] 6.77, 95% CI 3.22-14.24; P < .001) and in-hospital (42.3% vs 14.0%; OR 4.47, 95% CI 2.34-8.51; P < .001) versus the extubation success group. Multivariate logistic regression analyses showed that re-intubation within 48 h was independently associated with both ICU mortality (OR 6.10, 95% CI 2.84-13.07; P < .001) and in-hospital mortality (OR 3.36, 95% CI 1.67-6.73; P = .001). In-hospital mortality was also associated with rescue noninvasive ventilation after extubation (OR 2.44, 95% CI 1.25-4.75; P = .009). Re-intubation within 48 h after planned extubation was associated with mortality in subjects who were critically ill.

MUltiparametric Score for Ventilation Discontinuation in Intensive Care Patients: A Protocol for an Observational Study.

Mechanical ventilation significantly improves patient survival but is associated with complications, increasing healthcare costs and morbidity. Identifying optimal weaning times is paramount to minimize these risks, yet current methods rely heavily on clinical judgment, lacking specificity. This study introduces a novel multiparametric predictive score, the MUSVIP (MUltiparametric Score for Ventilation discontinuation in Intensive care Patients), aimed at accurately predicting successful extubation. Conducted at Santo Stefano Hospital's ICU, this single-center, observational, prospective cohort study will span over 12 months, enrolling adult patients undergoing invasive mechanical ventilation. The MUSVIP integrates variables measured before and during a spontaneous breathing trial (SBT) to formulate a predictive score. Preliminary analyses suggest an Area Under the Curve (AUC) of 0.815 for the MUSVIP, indicating high predictive capacity. By systematically applying this score, we anticipate identifying patients likely to succeed in weaning earlier, potentially reducing ICU length of stay and associated healthcare costs. This study's findings could significantly influence clinical practices, offering a robust, easy-to-use tool for optimizing weaning processes in ICUs.

Daily compliance of the ABCDEF liberation bundle for patients in the intensive care unit: A retrospective descriptive study

Implementing the ABCDEF bundle has demonstrated improved outcomes in patients with critical illness. This study aims to describe the daily compliance of the ABCDEF bundle in a Chilean intensive care unit. Retrospective observational study of electronic clinical records of nursing, physiotherapy, and medical professionals who cared for patients over 18 years of age, admitted to an intensive care unit for at least 24 hours, with or without mechanical ventilation. Daily bundle compliance was determined by considering the daily records for each element: Assess pain (element A), both spontaneous awakening trials (element B1) and spontaneous breathing trials (element B2), choice of sedation (element C), delirium assessment (element D), early mobilization (element E), and family engagement (element F). 4165 registered bundle elements were obtained from nursing (47%), physiotherapy (44%), and physicians (7%), including 1134 patient/days (from 133 patients). Elements E and C showed 67 and 40% compliance, while D, A, and B2 showed 24, 14 and 11%, respectively. For B1 and F, 0% compliance was achieved. Compliance was higher in patients without mechanical ventilation for A and E, while it was similar for D. Early mobilization had the highest compliance, while spontaneous awakening trials and family engagement had absolute non-compliance. Future studies should explore the reasons for the different degrees of compliance per bundle element in clinical practice.

Tissue Doppler imaging of the diaphragm and outcome of weaning from mechanical ventilation.

This study aimed to employ tissue Doppler imaging to monitor diaphragmatic peak velocity and acceleration during contraction and relaxation in mechanically ventilated patients, with the objective of assessing the potential utility of this technique in predicting weaning outcomes. A total of 89 adult subjects were recruited in this study. After 30 min of spontaneous breathing trial, the diaphragm motion parameters, including peak contraction velocity, peak relaxation velocity, contraction acceleration and relaxation acceleration, were measured in real time using tissue Doppler imaging. According to the results of weaning, the patients were divided into successful weaning group and failed weaning group. The differences of diaphragmatic tissue Doppler imaging monitoring indicators between the two groups were analysed, and the receiver operating characteristic curve was drawn to analyse the value of each ultrasound parameter in predicting weaning. In the successful weaning group, there were 61 subjects, while in the failed weaning group, there were 28 subjects. The peak contraction velocity, peak relaxation velocity, contraction acceleration and relaxation acceleration of the diaphragm were significantly higher in the failed weaning group compared to the successful weaning group (P < 0.05). The area under the curve of diaphragmatic peak contraction velocity, peak relaxation velocity, diaphragmatic contraction acceleration and diaphragmatic relaxation acceleration were 0.81 (0.72-0.91), 0.85 (0.77-0.93), 0.74 (0.63-0.86) and 0.86 (0.78-0.94), respectively. The diaphragm ultrasonic tissue Doppler imaging variables can serve as predictive indicators for weaning mechanical ventilation in patients, thus providing an effective tool to assist critical care physicians in determining the optimal timing for weaning mechanical ventilation.

Assessing the reproducibility and predictive value of objective cough measurement for successful withdrawal of invasive ventilatory support in adult patients

BackgroundUtilizing clinical tests, such as objective cough measurement, can assist in predicting the success of the weaning process in critically ill patients.MethodsA multicenter observational analytical study was conducted within a prospective cohort of patients recruited to participate in COBRE-US. We assessed the capability of objective cough measurement to predict the success of the spontaneous breathing trial (SBT) and extubation. Intra- and inter-observer reproducibility of the cough test and was evaluated using the intraclass correlation coefficient (ICC) and Cohen’s weighted kappa. We used receiver operating characteristic curves (ROC-curve) to evaluate the predictive ability of objective cough measurement.ResultsWe recruited 367 subjects who were receiving invasive mechanical ventilation. A total of 451 objective cough measurements and 456 SBTs were conducted. A significant association was found between objective cough measurement and successful SBT (OR: 1.68; 95% CI 1.48–1.90; p = 0.001). The predictive capability of the objective cough test for SBT success had a ROC-curve of 0.58 (95% CI: 0.56–0.61). Objective cough measurement to predict successful extubation had a ROC-curve of 0.61 (95% CI: 0.56–0.66). The intraobserver reproducibility exhibited an ICC of 0.94 (95% CI: 0.89–0.96; p < 0.001), while the interobserver reproducibility demonstrated an ICC of 0.72 (95% CI: 0.51–0.85; p < 0.001). The intraobserver agreement, assessed using Cohen’s weighted kappa was 0.94 (95% CI: 0.93–0.99; p < 0.001), whereas the interobserver agreement was 0.84 (95% CI: 0.67 − 0.10; p < 0.001).ConclusionsThe objective measurement of cough using the method employed in our study demonstrates nearly perfect intra-observer reproducibility and agreement. However, its ability to predict success or failure in the weaning process is limited.

High-Risk Extubation Readiness Testing for Children With Cardiac Critical Illness.

A protocolized extubation readiness test (ERT), including a spontaneous breathing trial (SBT), is recommended for patients who are intubated. This quality-improvement project aimed to improve peri-extubation outcomes by using a high-risk ERT protocol in intubated cardiac patients in addition to a standard-risk protocol. After baseline data collection, we implemented a standard-risk ERT protocol (pressure support plus PEEP), followed by a high-risk ERT protocol (PEEP alone) in cardiac subjects who were intubated. The primary outcome, a composite of extubation failure and rescue noninvasive respiratory support, was compared between phases. Ventilator duration and use of postextubation respiratory support were balancing measures. A total of 213 cardiac subjects who were intubated were studied, with extubation failure and rescue noninvasive respiratory support occurring in 10 of 213 (4.7%) and 8 of 213 (3.8%), respectively. We observed a reduction in the composite outcome among the 3 consecutive phases (5/29 [17.2%], 10/110 [9.1%] vs 3/74 [4.1%]; P = .10), but this did not reach statistical significance. In the logistic regression model when adjusting for admission type, the high-risk ERT protocol was associated with a significant reduction of the composite outcome (adjusted odds ratio 0.20, 95% CI 0.04-0.091; P = .037), whereas the standard-risk ERT protocol was not (adjusted odds ratio 0.48, 95% CI 0.15-1.53; P = .21). This was not accompanied by a longer ventilator duration (2.0 [1.0, 3.0], 2.0 [1.0-4.0], vs adjusted odds ratio 2.0 [95% [1.0-6.0]; P = .99) or an increased use of planned noninvasive respiratory support (10/29 [35.5%], 35/110 [31.8%], vs 25/74 [33.8%]; P > .99). In this quality-improvement project, a high-risk ERT protocol was implemented with improvement in peri-extubation outcomes among cardiac subjects.

Electrical Impedance Tomography as a monitoring tool during weaning from mechanical ventilation: an observational study during the spontaneous breathing trial

BackgroundProlonged weaning from mechanical ventilation is associated with poor clinical outcome. Therefore, choosing the right moment for weaning and extubation is essential. Electrical Impedance Tomography (EIT) is a promising innovative lung monitoring technique, but its role in supporting weaning decisions is yet uncertain. We aimed to evaluate physiological trends during a T-piece spontaneous breathing trail (SBT) as measured with EIT and the relation between EIT parameters and SBT success or failure.MethodsThis is an observational study in which twenty-four adult patients receiving mechanical ventilation performed an SBT. EIT monitoring was performed around the SBT. Multiple EIT parameters including the end-expiratory lung impedance (EELI), delta Tidal Impedance (ΔZ), Global Inhomogeneity index (GI), Rapid Shallow Breathing Index (RSBIEIT), Respiratory Rate (RREIT) and Minute Ventilation (MVEIT) were computed on a breath-by-breath basis from stable tidal breathing periods.ResultsEELI values dropped after the start of the SBT (p < 0.001) and did not recover to baseline after restarting mechanical ventilation. The ΔZ dropped (p < 0.001) but restored to baseline within seconds after restarting mechanical ventilation. Five patients failed the SBT, the GI (p = 0.01) and transcutaneous CO2 (p < 0.001) values significantly increased during the SBT in patients who failed the SBT compared to patients with a successful SBT.ConclusionEIT has the potential to assess changes in ventilation distribution and quantify the inhomogeneity of the lungs during the SBT. High lung inhomogeneity was found during SBT failure. Insight into physiological trends for the individual patient can be obtained with EIT during weaning from mechanical ventilation, but its role in predicting weaning failure requires further study.

Impact of a Rounding Checklist Implementation in the Trauma Intensive Care Unit on Clinical Outcomes.

We aimed to evaluate the effectiveness of an intensive care unit (ICU) round checklist, FAST HUGS BID (Feeding, Analgesia, Sedation, Thromboembolic prophylaxis, Head-of-bed elevation, Ulcer prophylaxis, Glycemic control, Spontaneous breathing trial, Bowel regimen, Indwelling catheter removal, and De-escalation of antibiotics-abbreviated as FD hereafter), in improving clinical outcomes in patients with severe trauma. We included patients admitted to our trauma ICU from 2016 to 2020 and divided them into two groups: before (before-FD, 2016-2017) and after (after-FD, 2019-2020) implementation of the checklist. We compared patient characteristics and clinical outcomes, including ICU and hospital length of stay (LOS) and in-hospital mortality. Survival analysis was performed using Kaplan-Meier curves and multivariable logistic regression models; furthermore, multiple linear regression analysis was used to identify independent factors associated with ICU and hospital LOS. Compared with the before-FD group, the after-FD group had significantly lower in-hospital mortality and complication rates, shorter ICU and hospital LOS, and reduced duration of mechanical ventilation. Moreover, implementation of the checklist was a significant independent factor in reducing ICU and hospital LOS and in-hospital mortality. Implementation of the FD checklist is associated with decreased ICU and hospital LOS and in-hospital mortality.

Combined cardiac, lung, and diaphragm ultrasound for predicting weaning failure during spontaneous breathing trial

BackgroundWeaning from invasive mechanical ventilation (MV) is a complex and challenging process that involves multiple pathophysiological mechanisms. A combined ultrasound evaluation of the heart, lungs, and diaphragm during the weaning phase can help to identify risk factors and underlying mechanisms for weaning failure. This study aimed to investigate the accuracy of lung ultrasound (LUS), transthoracic echocardiography (TTE), and diaphragm ultrasound for predicting weaning failure in critically ill patients.MethodsPatients undergoing invasive MV for > 48 h and who were readied for their first spontaneous breathing trial (SBT) were studied. Patients were scheduled for a 2-h SBT using low-level pressure support ventilation. LUS and TTE were performed prospectively before and 30 min after starting the SBT, and diaphragm ultrasound was only performed 30 min after starting the SBT. Weaning failure was defined as failure of SBT, re-intubation, or non-invasive ventilation within 48 h.ResultsFifty-one patients were included, of whom 15 experienced weaning failure. During the SBT, the global, anterior, and antero-lateral LUS scores were higher in the failed group than in the successful group. Receiver operating characteristic curve analysis showed that the areas under the curves for diaphragm thickening fraction (DTF) and global and antero-lateral LUS scores during the SBT to predict weaning failure were 0.678, 0.719, and 0.721, respectively. There was no correlation between the LUS scores and the average E/e’ ratio during the SBT. Multivariate analysis identified antero-lateral LUS score > 7 and DTF < 31% during the SBT as independent predictors of weaning failure.ConclusionLUS and diaphragm ultrasound can help to predict weaning failure in patients undergoing an SBT with low-level pressure support. An antero-lateral LUS score > 7 and DTF < 31% during the SBT were associated with weaning failure.Graphical

Fluid Responsiveness Is Associated with Successful Weaning after Liver Transplant Surgery.

A positive fluid balance may evolve to fluid overload and associate with organ dysfunctions, weaning difficulties, and increased mortality in ICU patients. We explored whether individualized fluid management, assessing fluid responsiveness via a passive leg-raising maneuver (PLR) before a spontaneous breathing trial (SBT), is associated with less extubation failure in ventilated patients with a high fluid balance admitted to the ICU after liver transplantation (LT). We recruited 15 LT patients in 2023. Their postoperative fluid balance was +4476 {3697, 5722} mL. PLR maneuvers were conducted upon ICU admission (T1) and pre SBT (T2). Cardiac index (CI) changes were recorded before and after each SBT (T3). Seven patients were fluid-responsive at T1, and twelve were responsive at T2. No significant differences occurred in hemodynamic, respiratory, and perfusion parameters between the fluid-responsive and fluid-unresponsive patients at any time. Fluid-responsive patients at T1 and T2 increased their CI during SBT from 3.1 {2.8, 3.7} to 3.7 {3.4, 4.1} mL/min/m2 (p = 0.045). All fluid-responsive patients at T2 were extubated after the SBTs and consolidated extubation. Two out of three of the fluid-unresponsive patients experienced weaning difficulties. We concluded that fluid-responsive patients post LT may start weaning earlier and achieve successful extubation despite a high postoperative fluid balance. This highlights the profound impact of personalized assessments of cardiovascular state on critical surgical patients.

Spontaneous breathing trial with pressure support on positive end-expiratory pressure and extensive use of non-invasive ventilation versus T-piece in difficult-to-wean patients from mechanical ventilation: a randomized controlled trial

BackgroundThe aim of this study is to assess whether a strategy combining spontaneous breathing trial (SBT) with both pressure support (PS) and positive end-expiratory pressure (PEEP) and extended use of post-extubation non-invasive ventilation (NIV) (extensively-assisted weaning) would shorten the time until successful extubation as compared with SBT with T-piece (TP) and post-extubation NIV performed in selected patients as advocated by guidelines (standard weaning), in difficult-to-wean patients from mechanical ventilation.MethodsThe study is a single-center prospective open label, randomized controlled superiority trial with two parallel groups and balanced randomization with a 1:1 ratio. Eligible patients were intubated patients mechanically ventilated for more than 24 h who failed their first SBT using TP. In the extensively-assisted weaning group, SBT was performed with PS (7 cmH2O) and PEEP (5 cmH2O). In case of SBT success, an additional SBT with TP was performed. Failure of this SBT-TP was an additional criterion for post-extubation NIV in this group in addition to other recommended criteria. In the standard weaning group, SBT was performed with TP, and NIV was performed according to international guidelines. The primary outcome criterion was the time between inclusion and successful extubation evaluated with a Cox model with adjustment on randomization strata.ResultsFrom May 2019 to March 2023, 98 patients were included and randomized in the study (49 in each group). Four patients were excluded from the intention-to-treat population (2 in both groups); therefore, 47 patients were analyzed in each group. The extensively-assisted weaning group had a higher median age (68 [58–73] vs. 62 [55–71] yrs.) and similar sex ratio (62% male vs. 57%). Time until successful extubation was not significantly different between extensively-assisted and standard weaning groups (median, 172 [50–436] vs. 95 [47–232] hours, Cox hazard ratio for successful extubation, 0.88 [95% confidence interval: 0.55–1.42] using the standard weaning group as a reference; p = 0.60). All secondary outcomes were not significantly different between groups.ConclusionAn extensively-assisted weaning strategy did not lead to a shorter time to successful extubation than a standard weaning strategy.Trial registration The trial was registered on ClinicalTrials.gov (NCT03861117), on March 1, 2019, before the inclusion of the first patient. https://clinicaltrials.gov/study/NCT03861117.

EFFECTS OF LEVOSIMENDAN ON DIAPHRAGMATIC DYSFUNCTION IN PATIENTS WITH SEPSIS.

Objective: In this study, our aim was to examine the effects of levosimendan on diaphragmatic dysfunction in patients with sepsis, as well as assess its impact on respiratory muscle contractility and the outcome of weaning. Methods: This was a single-blind, randomized, controlled trial. Patients with diaphragmatic dysfunction and failure of spontaneous breathing trials (SBTs) were randomly and equally assigned to the experimental and control groups. The experimental group received levosimendan at a loading dose of 6 μg/kg for 10 min, followed by a continuous infusion at 0.2 μg/kg/min. The control group received an equivalent dose of a placebo. The preadministration and postadministration respiratory mechanics parameters of the patients were recorded. Evaluation of the effect of levosimendan on patients with sepsis-induced diaphragm dysfunction comprised arterial blood gas analysis as well as ultrasound measurements of diaphragm excursion (DE), diaphragm thickness (DT), diaphragm thickening fraction (TFdi), and diaphragm-rapid shallow breathing index (D-RSBI). Results: Forty-four patients were enrolled in the study. We found that postadministration of levosimendan, the patients' tidal volume (GCSMV) increased, whereas the D-RSBI decreased, and the partial pressure of carbon dioxide (PACO 2 ) decreased when compared to the preadministration levels. Additionally, following levosimendan administration, patients showed increased DE and pressure support (PS) when compared to before administration (1.14 ± 0.177 vs. 1.22 ± 0.170 cm and 0.248 ± 0.03 vs. 0.284 ± 0.06, respectively) and decreased D-RSBI (22.76 ± 6.14 vs. 20.06 ± 6.04, respectively), all of which were statistically significant ( P < 0.05). In contrast, in the control group of patients, there were no statistically significant differences in the postadministration levels of DE, TFdi, and D-RSBI as compared to the preadministration period ( P > 0.05). Furthermore, in terms of weaning outcomes, we did not find any statistically significant difference in the number of patients in the two groups who eventually underwent weaning ( P = 0.545). Conclusion: In this study, we found that levosimendan enhanced diaphragm contractile function. However, further investigations are required to explore its effect on weaning outcomes in patients undergoing mechanical ventilation.

Reducing Airway Occlusion Time Without Losing Accuracy to Predict Successful Mechanical Ventilator Liberation During the Measurement of the Timed Inspiratory Effort Index.

In 2013, a new predictor of successful mechanical ventilation liberation named timed inspiratory effort (TIE) index was devised with the normalization of the maximum inspiratory pressure (obtained within 60 s of unidirectional airway occlusion) with the time at which the value was reached. The aim of this study was to verify whether the presence of a sequence of a certain number of inspiratory effort values between 30-60 s > 1.0 cm H2O/s could predict weaning success in a performance comparable to the TIE index. This was a retrospective observational study using 4 databases of previous studies on the TIE index. All patients receiving mechanical ventilation for ≤ 24 h were eligible. Liberation from mechanical ventilation-extubation decisions was made based on performance with spontaneous breathing trials. P < .05 was considered significant. The performance of the TIE index was evaluated by calculating the area under the receiver operating characteristics (AUROC) curve. From 349 eligible patients, 165 subjects were selected for analysis. The AUROC for the TIE index in the studied sample was 0.92 (95% CI 0.87-0.97, P < .001). A sequence of ≤ 4 inspiratory efforts > 1.0 cm H2O/s was found in 51.5% of the subjects, with successful ventilatory liberation occurring in 95.3%. The highest specificity values belonged to the sequence of ≤ 4 and ≤ 5 inspiratory efforts > 1.0 cm H2O/s; the highest positive predictive value and positive likelihood ratio belonged to the sequence of ≤ 4 inspiratory efforts > 1.0 cm H2O/s. The mean time that could have been spared if the procedure were interrupted after the first sequence of 4 inspiratory efforts > 1.0 cm H2O/s was 23 ± 3 s. The presence of a sequence of ≤ 4 inspiratory efforts > 1.0 cm H2O/s during the TIE index measurement was a reliable predictor of weaning success, which could allow timely interruption of the procedure and entail a substantial reduction in airway occlusion time.

Important step of weaning from mechanical ventilation: accurate assessment of respiratory muscle strength

Mechanical ventilation (MV) is a powerful mean to rescue patients with respiratory failure. In view of the different etiology and basic respiratory function of patients with respiratory failure, weaning failure often occurs. Prolonged MV time is often accompanied by many complications. Thus, deeply understanding the pathophysiological changes of respiratory failure and strengthen monitoring of respiratory mechanics are helpful to optimize MV parameter settings, reduce ventilator-induced lung injury and wean from MV as early as possible. A successful weaning from MV depends on many factors, the most important factors are respiratory muscle strength, respiratory load and respiratory drive. Spontaneous breathing trial (SBT) is an important part of weaning process. The main purpose of implementing SBT is to screen patients and opportunities to weaning from MV, and find reversible reasons for not passing SBT. Because the accuracy of SBT in assessing weaning prognosis is about 85%, it is not adequate for difficult weaning patients. Standardized measurement of weaning indicators for patients with difficulty weaning is conducive to accurate assessment of respiratory muscle strength and improve the success rate of weaning from MV.

Development of a machine learning model for prediction of the duration of unassisted spontaneous breathing in patients during prolonged weaning from mechanical ventilation

PurposeTreatment of patients undergoing prolonged weaning from mechanical ventilation includes repeated spontaneous breathing trials (SBTs) without respiratory support, whose duration must be balanced critically to prevent over- and underload of respiratory musculature. This study aimed to develop a machine learning model to predict the duration of unassisted spontaneous breathing. Materials and methodsStructured clinical data of patients from a specialized weaning unit were used to develop (1) a classifier model to qualitatively predict an increase of duration, (2) a regressor model to quantitatively predict the precise duration of SBTs on the next day, and (3) the duration difference between the current and following day. 61 features, known to influence weaning, were included into a Histogram-based gradient boosting model. The models were trained and evaluated using separated data sets. Results18.948 patient-days from 1018 individual patients were included. The classifier model yielded an ROC-AUC of 0.713. The regressor models displayed a mean absolute error of 2:50 h for prediction of absolute durations and 2:47 h for day-to-day difference. ConclusionsThe developed machine learning model showed informed results when predicting the spontaneous breathing capacity of a patient in prolonged weaning, however lacking prognostic quality required for direct translation to clinical use.

Effects of hyperbaric oxygen combined cabin ventilator on critically ill patients with liberation difficulty after tracheostomy

BackgroundCritically ill patients undergoing liberation often encounter various physiological and clinical complexities and challenges. However, whether the combination of hyperbaric oxygen and in-cabin ventilator therapy could offer a comprehensive approach that may simultaneously address respiratory and potentially improve outcomes in this challenging patient population remain unclear.MethodsThis retrospective study involved 148 patients experiencing difficulty in liberation after tracheotomy. Inclusion criteria comprised ongoing mechanical ventilation need, lung inflammation on computed tomography (CT) scans, and Glasgow Coma Scale (GCS) scores of ≤ 9. Exclusion criteria excluded patients with active bleeding, untreated pneumothorax, cerebrospinal fluid leakage, and a heart rate below 50 beats per minute. Following exclusions, 111 cases were treated with hyperbaric oxygen combined cabin ventilator, of which 72 cases were successfully liberated (SL group) and 28 cases (NSL group) were not successfully liberated. The hyperbaric oxygen chamber group received pressurization to 0.20 MPa (2.0 ATA) for 20 min, followed by 60 min of ventilator oxygen inhalation. Successful liberation was determined by a strict process, including subjective and objective criteria, with a prolonged spontaneous breathing trial. GCS assessments were conducted to evaluate consciousness levels, with scores categorized as normal, mildly impaired, moderately impaired, or severely impaired.ResultsPatients who underwent treatment exhibited improved GCS, blood gas indicators, and cardiac function indexes. The improvement of GCS, partial pressure of oxygen (PaO2), oxygen saturation of blood (SaO2), oxygenation index (OI) in the SL group was significantly higher than that of the NSL group. However, there was no significant difference in the improvement of left ventricular ejection fraction (LVEF), left ventricular end-systolic volume (LVESV), left ventricular end-diastolic volume (LVEDV), and stroke volume (SV) between the SL group and the NSL group after treatment.ConclusionsHyperbaric oxygen combined with in-cabin ventilator therapy effectively enhances respiratory function, cardiopulmonary function, and various indicators of critically ill patients with liberation difficulty after tracheostomy.

AARC Clinical Practice Guideline: Spontaneous Breathing Trials for Liberation From Adult Mechanical Ventilation.

Despite prior publications of clinical practice guidelines related to ventilator liberation, some questions remain unanswered. Many of these questions relate to the details of bedside implementation. We, therefore, formed a guidelines committee of individuals with experience and knowledge of ventilator liberation as well as a medical librarian. Using Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology, we make the following recommendations: (1) We suggest that calculation of a rapid shallow breathing index is not needed to determine readiness for a spontaneous breathing trial (SBT) (conditional recommendation; moderate certainty); (2) We suggest that SBTs can be conducted with or without pressure support ventilation (conditional recommendation, moderate certainty); (3) We suggest a standardized approach to assessment and, if appropriate, completion of an SBT before noon each day (conditional recommendation, very low certainty); and (4) We suggest that FIO2 should not be increased during an SBT (conditional recommendation, very low certainty). These recommendations are intended to assist bedside clinicians to liberate adult critically ill patients more rapidly from mechanical ventilation.

Risk factor profile and extubation outcomes in critically ill patients. A single-center prospective observational study

Background: The problem of extubation failure (EF) remains unexplored in low-resource settings, where predicting the extubation outcomes are more challenging. Aims and Objectives: This study investigates the incidence of EF and its predictors among patients who received mechanical ventilation (MV) in a tertiary care intensive care unit (ICU). Materials and Methods: This is a prospective observational study of 130 patients ≥18 years of age receiving MV for ≥48 h and tolerating spontaneous breathing trials in the ICU of a low-resource setting. We collected data on the baseline characteristics and clinical profiles. Patients were categorized into EF and extubation success (ES) groups. Multivariate logistic regression analyses were performed to identify independent predictors for EF. A p value of &lt;0.05 is considered statistically significant. Results: We included 130 patients, and 43 (35.3%) had developed EF. The identified predictors for EF: Moderate to copious secretions (adjusted odds ratio [AOR]: 3.426 [95% confidence interval [CI] 1.281–10.82]), age &gt;60 years of age ([AOR]: 4.135 [95% CI 1.294–11.93]), and prolonged duration of MV ≥10 days ([AOR]: 4.571 [95% CI 1.392–15.33]). Conclusion: Moderate to copious secretions, patients &gt;60 years of age, and prolonged duration of MV ≥10 days were the best predictors of EF.