Successful Spontaneous Breathing Trial Research Articles

Prediction of Weaning Outcome from Mechanical Ventilation Using Diaphragmatic Rapid Shallow Breathing Index.

ABSTRACTBackgroundDiaphragmatic dysfunction has been increasingly documented to play a critical role to determine ventilator dependency and failure of weaning.ObjectiveThe goal was to study the diagnostic accuracy of diaphragmatic rapid shallow breathing index (D-RSBI) as a predictor of weaning outcomes in comparison to RSBI.Materials and methodsA prospective observational study on consecutively admitted patients who were intubated and mechanically ventilated for a duration of at least 48 hours was carried out. The right hemidiaphragm displacement [diaphragm displacement (DD)] was calculated by M-mode ultrasonography, and respiratory rate (RR) and tidal volume (TV) were documented from the ventilator readings. Rapid shallow breathing index (RSBI) was measured as RR/TV (in liters); D-RSBI was calculated as RR/DD (in millimeters) and expressed as breath/minute/millimeter. Extubation failure was defined as the reinstitution of mechanical ventilation at the end of, or during the spontaneous breathing trial (SBT), re-intubation or the need of noninvasive ventilation (NIV) for the patient within 48 hours of extubation.ResultsOf 101 screened patients, 50 patients met the inclusion criteria, of whom 45 patients had successful SBT, and finally, 41 patients could be successfully extubated. Hence, the overall rate of weaning failure in the study population was 18%. The areas under the receiver operator characteristic (ROC) curves for D-RSBI and RSBI were 0.97 and 0.70, respectively (p <0.0001). The Pearson's correlation among RSBI and D-RSBI was 0.81 (p-value <0.001).ConclusionDiaphragmatic rapid shallow breathing index has a positive correlation and greater diagnostic accuracy than RSBI, the conventional weaning index.How to cite this articleShamil PK, Gupta NK, Ish P, Sen MK, Kumar R, Chakrabarti S, et al. Prediction of Weaning Outcome from Mechanical Ventilation Using Diaphragmatic Rapid Shallow Breathing Index. Indian J Crit Care Med 2022;26(9):1000–1005.

Automatic Tube Compensation During Spontaneous Breathing Trials.

Automatic tube compensation (ATC) is an option available in any ICU ventilator that compensates for the resistive pressure drop due to the endotracheal tube. The goal of the present study was to compare ATC to other patient triggered modes of support in terms of spontaneous breathing trial (SBT) and extubation success. Two authors (JB and PCF), independently and blinded to each other, searched through PubMed, Web of Science, and Cochrane from inception-May 26, 2021, with the following search terms entered as MeSH terms in all fields: "Automatic Tube Compensation." randomized studies that included subjects > 16 y old undergoing an SBT. crossover studies, pediatric studies, animal studies, or experimental studies on test lungs or on computer simulation; other languages than French, Spanish, or English; studies not published in a full-text format (eg, abstract or letter); and reviews. A frequentist network meta-analysis was conducted with the aim to investigate the effectiveness of ATC on SBT and extubation outcomes. SBT was defined as successful if patients could tolerate the SBT based on predetermined criteria, whether it was followed by extubation. Successful extubation was defined as the absence of re-intubation, noninvasive ventilation, or signs of respiratory distress within the 48 h after extubation. The pooled analyses used random-effect models, and the effect size was expressed as relative risk or mean difference for categorical and continuous variables, respectively. P-scores were used to rank all treatments and to identify the intervention with the highest probability of being the best. Of the 234 retrieved papers, 7 met the inclusion criteria. In terms of SBT success, ATC100+PEEP < 7.5 and PS10+PEEP < 7.5 were superior to T-piece. Likewise, PS10+PEEP < 7.5 was the intervention with the highest probability of being the best (P-score: 0.90). In terms of extubation success, ATC100+PEEP < 7.5 cm H2O was significantly better than PEEP < 7.5 and T-piece. Likewise, it had the highest probability of being the best (P-score= 0.90). ATC is the modality with the highest probability of extubation success but not in terms of SBT success.

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.

Prediction Model of Extubation Outcomes in Critically Ill Patients: A Multicenter Prospective Cohort Study.

Liberation from mechanical ventilation is of great importance owing to related complications from extended ventilation time. In this prospective multicenter study, we aimed to construct a versatile model for predicting extubation outcomes in critical care settings using obtainable physiological predictors. The study included patients who had been extubated after a successful 30 min spontaneous breathing trial (SBT). A multivariable logistic regression model was constructed to predict extubation outcomes (successful extubation without reintubation and uneventful extubation without reintubation or noninvasive respiratory support) using eight parameters: age, heart failure, respiratory disease, rapid shallow breathing index (RSBI), PaO2/FIO2, Glasgow Coma Scale score, fluid balance, and endotracheal suctioning episodes. Of 499 patients, 453 (90.8%) and 328 (65.7%) achieved successful and uneventful extubation, respectively. The areas under the curve for successful and uneventful extubation in the novel prediction model were 0.69 (95% confidence interval (CI), 0.62–0.77) and 0.70 (95% CI, 0.65–0.74), respectively, which were significantly higher than those in the conventional model solely using RSBI (0.58 (95% CI, 0.50–0.66) and 0.54 (95% CI, 0.49–0.60), p = 0.004 and <0.001, respectively). The model was validated using a bootstrap method, and an online application was developed for automatic calculation. Our model, which is based on a combination of generally obtainable parameters, established an accessible method for predicting extubation outcomes after a successful SBT.

Evaluation of the Integrative Weaning Index for Predicting the Outcome of Spontaneous Breathing Trial in Patients with Cirrhosis on Mechanical Ventilation: A Pilot Study.

Objective:Studies on mechanical ventilation in patients with cirrhosis have focused mainly on survival, as the disease is considered to carry a poor prognosis. The process of weaning in these patients has never been studied. With improving survival, it would be ideal to study the weaning indices that could add experience in clinical management. The integrative weaning index is known to predict weaning failure, even in those who tolerate the spontaneous breathing trial. However, it has been evaluated mainly in patients with chronic obstructive pulmonary disease. Our aim is to study the integrative weaning index in predicting the outcome of the spontaneous breathing trial in patients with cirrhosis undergoing mechanical ventilation.Methods:Adult cirrhotic patients requiring mechanical ventilation for the first time were enrolled. Twenty-seven patients were found eligible for weaning. After the decision to wean, the patients were put on pressure support mode of ventilator followed by spontaneous breathing trial using T-piece for 2 hours.Results:The study population was divided into two groups: successful spontaneous breathing trial group (Group S) and unsuccessful spontaneous breathing trial group (Group U) based on the outcome of the breathing trial. The mean respiratory rate was significantly lower in Group S as compared to Group U. The compliance of the respiratory system and integrative weaning index were found to be significantly higher in Group S. An integrative weaning index of 28 mL/cmH2O breaths/min/L was found to be a good predictor of weaning success.Conclusions:Our results demonstrate that weaning from mechanical ventilation is possible in critically ill patients with cirrhosis. An integrative weaning index of 28 mL/cmH2O breaths/min/L could be a successful predictor of weaning from mechanical ventilation.

1-hour t-piece spontaneous breathing trial vs 1-hour zero pressure support spontaneous breathing trial and reintubation at day 7: A non-inferiority approach

Physiological data suggest that T-piece and zero pressure support (PS0) ventilation both accurately reflect spontaneous breathing conditions after extubation. These two types of spontaneous breathing trials (SBTs) are used in our Intensive Care Unit to evaluate patients for extubation readiness and success but have rarely been compared in clinical studies. We performed a prospective observational study to confirm the hypothesis that 1-hour T-piece SBT and 1-h PS0 zero PEEP (ZEEP) SBT are associated with similar rates of reintubation at day 7 after extubation. A non-inferiority approach was used for sample size calculation. The cohort consisted of 529 subjects invasively ventilated for more than 24h and extubated after successful 1-hour T-piece SBT (n=303, 57%) or 1-h PS0 ZEEP SBT (n=226, 43%). The reintubation rate at day 7 was 14.6% with PS0 ZEEP and 17.5% with T-piece (difference-2.6% [95% confidence interval, -8.3% to 4.3%]; p=0.40). The reasons for reintubation did not differ significantly when compared between patients with 1-h PS0 ZEEP SBT and patients with 1-hour T-piece SBT. Our results suggest that successful 1-hour T-piece and 1-h PSO ZEEP SBTs are associated with similar reintubation rates at day 7.

COVID-19 with peripartum cardiomyopathy: a case report

BackgroundThe world has been facing the novel coronavirus SARS-CoV-2 pandemic. The novel coronavirus primarily affects the lungs but also affects multiple organ systems including the cardiovascular system causing myocarditis, cardiomyopathy, and arrhythmias. Cardiomyopathy has been reported in patients with COVID-19; however, prognosis of peripartum cardiomyopathy in a patient with COVID-19 is still unexplored. More knowledge is required to understand the incidence of cardiomyopathy due to novel coronavirus SARS-CoV-2.Case presentationWe report a case of peripartum cardiomyopathy gravida 2 parity 2 COVID-19 confirmed patient who underwent an emergency preterm lower segment caesarean section (LSCS) for severe pre-eclampsia and intra-uterine growth retardation (IUGR) and landed up in acute congestive cardiac failure with pulmonary oedema. A postpartum 32 years female presented to our institute, a dedicated COVID-19 hospital with tachycardia, hypertension, anasarca, tachypnea with desaturation on room air. She had undergone emergency caesarean section for severe preeclampsia with intrauterine growth retardation. On post-operative day 2 (POD2), she complained of shortness of breath. On POD 3 she tested positive RT-PCR for COVID-19 infection. She responded to treatment with steroids. However, on POD6, She developed severe pulmonary oedema with poor ejection fraction necessitating endotracheal intubation and pressure control ventilation. Congestive cardiac failure was managed with diuretics and digoxin. Gradually oxygenation improved. She was electively ventilated for 3 days. Gradually, ejection fraction improved with the resolution of B lines. On the 9th POD, after a successful spontaneous breathing trial, she was extubated and non-invasive ventilation with bi-level positive airway pressure was attached. The patient was gradually tapered off of the non-invasive ventilation over 2 days. On the 11th post-operative day, she was maintaining oxygen saturation on nasal prongs and was sent to the ward.ConclusionsWe recommend early use of bedside lung ultrasonography; echocardiography and close cardiovascular monitoring in severe COVID-19 infected pregnant patients who present with shortness of breath, tachypnea, and hypertensive disorders of pregnancy and previous cardiac abnormalities for expedite management and improved prognosis. An ideal case scenario for extubation may not be present, non-invasive ventilation with bi-level positive airway pressure post-extubation helps in patients with peripartum cardiomyopathy.

Frequent tracheal suctioning is associated with extubation failure in patients with successful spontaneous breathing trial: a single-center retrospective cohort study

BackgroundExtubation failure, i.e., reintubation in ventilated patients, is a well-known risk factor for mortality and prolonged stay in the intensive care unit (ICU). Although sputum volume is a risk factor, the frequency of tracheal suctioning has not been validated as a predictor of reintubation. We conducted this study to examine whether frequent tracheal suctioning is a risk factor for reintubation.Patients and methodsWe included adult patients who were intubated for > 72 h in the ICU and extubated after completion of spontaneous breathing trial (SBT). We compared the characteristics and weaning-related variables, including the frequency of tracheal suctioning between patients who required reintubation within 24 h after extubation and those who did not, and examined the factors responsible for reintubation.ResultsOf the 400 patients enrolled, reintubation was required in 51 (12.8%). The most common cause of reintubation was difficulty in sputum excretion (66.7%). There were significant differences in sex, proportion of patients with chronic kidney disease, pneumonia, ICU admission type, the length of mechanical ventilation, and ICU stay between patients requiring reintubation and those who did not. Multivariate analysis showed frequent tracheal suction (> once every 2 h) and the length of mechanical ventilation were independent factors for predicting reintubation.ConclusionWe should examine the frequency of tracheal suctioning > once every 2 h in addition to the length of mechanical ventilation before deciding to extubate after completion of SBT in patients intubated for > 72 h in the ICU.

The Use of Transesophageal Doppler and Central Venous Oxygen Saturation as Predictors of Weaning Success

Weaning individuals from mechanical ventilation (MV) is a challenge to physicians. Respiratory failure is the main reason for weaning failure (WF), but heart failure plays a pivotal role as well. Transesophageal Doppler (TED) is a minimally invasive method of hemodynamic tracking with fewer problems. The study authors evaluated the role of TED in predicting WF. An observational study. A university teaching hospital. Weaning individuals. TED was applied before initiating the spontaneous breathing trial (SBT). Hemodynamic parameters, arterial blood gases, and TED (peak velocity [PV], cardiac output [COP]) were reported while cases were on MV before initiating the SBT, and at the successful completion of SBT. Succeeded (group S) and failed individuals (group F, who needed reintubation within 48 hours) were compared. The sensitivity, specificity, and area under the receiver operating curve were calculated. A subgroup of patients with cardiac comorbidities and impaired cardiac contractility was further analyzed. The authors included 39 critically ill patients for weaning from MV. The reintubation rate was 54.8%. In patients with cardiac morbidity, delta change (dC) in PV and COP as predictors of WF showed 100% sensitivity and specificity, with 18% and 14% cut-offs after initiating the SBT (dC between the beginning and end of the successful SBT), respectively. Central venous oxygen saturation revealed a significant difference between patients with cardiac morbidity and noncardiac patients with lower sensitivity and specificity in the prediction of WF. TED could be a helpful method for the weaning of patients with cardiac morbidity from MV. The dC in PV and COP >18% and >14% were significant predictors of WF in these subjects, respectively.

Integrated ultrasound protocol in predicting weaning success and extubation failure: aprospective observational study.

Difficulty in weaning from mechanical ventilation is encountered in appro-ximately 20% of patients in the intensive care unit. We assessed the utility of a combined lung, diaphragmatic, and cardiac ultrasound protocol to predict extubation failure. All patients extubated following a successful spontaneous breathing trial (SBT) were included in the study. Lung ultrasonography score (LUS), diaphragmatic thickness fraction (DTF), changes in velocity time integral (VTI) to passive leg raise at the beginning of SBT, and change in LUS following SBT were recorded. A total of 60 patients who underwent successful SBT were included in the study. Twenty-seven patients required either non-invasive or invasive mechanical ventilation during the next 48 hours and were classified as weaning failure (Group F). The remaining 33 patients were designated as weaning success (Group S). Compared to group S, patients in Group F had significantly longer ICU length of stay (6.96 ± 4.30 days vs. 11.66 ± 3.85 days, P < 0.001), higher LUS change during SBT (1 [0-2] vs. 2 [1-4], P < 0.001), lower DTF (30.87 ± 5.32 vs. 27.88 ± 6.24, P = 0.04), and showed lower VTI increment to PLR (13.63 ± 3.44 vs. 9.11 ± 4.59, P < 0.001). Using a binary logistic regression model, DTF < 26% (odds ratio 6.20, 95% CI: 1.06-36.04) and VTI change to PLR < 10.2% (odds ratio 6.16, 95% CI: 1.14-33.13) were found to be significant predictors of weaning failure (P < 0.05). The AUROC for VTI and DTF for predicting weaning failure were 0.79 and 0.64, respectively. An integrated ultrasound protocol using a combination of lung, diaphragm, and cardiac sonography was a reliable predictor of weaning failure.

Physiotherapy-assisted weaning in mechanically ventilated patient (Phast Wean)

Introduction: Patients requiring long-term mechanical ventilation often require a tracheostomy which may help with weaning from the ventilator. A key component of ventilator weaning is successful spontaneous breathing trials through the tracheostomy. The specialist skills of an ICU physiotherapist have been utilized for extended-scope roles, including performing bronchoscopies in ICU, members of an ICU outreach team, a MET Call team, and also leading a non-invasive ventilation team. The common theme with these roles is the utilization of the ICU physiotherapist’s specialized knowledge of respiratory function and ventilation.

Weaning Failure in Critically Ill Patients Is Related to the Persistence of Sepsis Inflammation.

Introduction: Septic patients undergoing mechanical ventilation (MV) often experience difficulty in weaning. Th aim of this study was to determine whether inflammatory biomarkers of sepsis could be indicative of the failure or success of spontaneous breathing trial (SBT) in these patients. Methods: Sixty-five patients on MV (42 septic and 23 intubated for other reasons) fulfilling the criteria for SBT were included in the study. Blood samples were collected right before, at the end of (30 min) and 24 h after the SBT. Serum inflammatory mediators associated with sepsis (IL-18, IL-18BP, TNF) were determined and correlated with the outcome of SBT. Results: A successful SBT was achieved in 45 patients (69.2%). Septic patients had a higher percentage of SBT failure as compared to non-septic patients (85% vs. 15%, p = 0.026), with an odds ratio for failing 4.5 times (OR = 4.5 95%CI: 1.16–17.68, p 0.022). IL-18 levels and the relative mRNA expression in serum were significantly higher in septic as compared to non-septic patients (p < 0.05). Sepsis was independently associated with higher serum IL-18 and TNF levels in two time-point GEE models (53–723, p = 0.023 and 0.3–64, p = 0.048, respectively). IL-18BP displayed independent negative association with rapid shallow breathing index (RSBI) (95% CI: −17.6 to −4, p = 0.002). Conclusion: Sustained increased levels of IL-18 and IL-18BP, acknowledged markers of sepsis, were found to be indicative of SBT failure in patients recovering from sepsis. Our results show that, although subclinical, remaining septic inflammation that sustaines for a long time complicates the weaning procedure. Biomarkers for the estimation of the septic burden and the right time for weaning are needed.

Re-Intubation Among Critical Care Patients: A Scoping Review

Objective: This paper aimed to identify relevant literature about what are the factors that contributing to the re-intubation and current intervention to overcome it among critical care patients. Methods: A scoping review was carried out with the 17 articles which publish with the year 2010 to 2021. The literature search was systematically done by using PRISMA flow diagram. The quality assessment was conducted by using Effective Public Health Practice Project (EPHPP) assessment tool and the authors applied inter-rater reliability for the included articles. Results: Four themes were emerged in this scoping review. Those were the criteria for extubation, factors of extubation failure and re-intubation, medical conditions associated with re-intubation, and intervention to reduce reintubation rate among critical care patients. Conclusion: The rate of re-intubation among critical care patients can be reduced when protective measures take place properly. Those are the use of non-invasive ventilation in between successful spontaneous breathing trials and extubation, the proper usage of analgesics and sedatives during extubation and monitoring the indicators like blood urea nitrogen and central venous pressure.

Comparative Efficacy and Safety of Four Different Spontaneous Breathing Trials for Weaning From Mechanical Ventilation: A Systematic Review and Network Meta-Analysis

Background: Spontaneous breathing trial (SBT) has been used to predict the optimal time of weaning from ventilator. However, it remains controversial which trial should be preferentially selected. We aimed to compare and rank four common SBT modes including automatic tube compensation (ATC), pressure support ventilation (PSV), continuous positive airway pressure (CPAP), and T-piece among critically ill patients receiving mechanical ventilation (MV).Methods: We searched PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials (CENTRAL) to identify studies that investigated the comparative efficacy and safety of at least two SBT strategies among critically ill patients up to May 17, 2020. We estimated the surface under the cumulative ranking curve (SUCRA) to rank SBT techniques, and determined the certainty of evidence using the Grading of Recommendations Assessment, Development and Evaluation method. Primary outcome was weaning success. Secondary outcomes were reintubation, SBT success, duration of acute care, and intensive care unit (ICU) mortality. Statistical analysis was conducted by using RevMan 5.4, Stata, and R software.Results: We enrolled 24 trials finally. Extubation success rate was significantly higher in ATC than that in T-piece (OR, 0.28; 95% CI, 0.13–0.64) or PSV (OR, 0.53; 95% CI, 0.32–0.88). For SBT success, ATC was better than other SBT techniques, with a pooled OR ranging from 0.17 to 0.42. For reintubation rate, CPAP was worse than T-piece (OR, 2.76; 95% CI, 1.08 to 7.06). No significant difference was detected between SBT modes for the length of stay in ICU or long-term weaning unit (LWU). Similar result was also found for ICU mortality between PSV and T-piece. Majority direct results were confirmed by network meta-analysis. Besides, ATC ranks at the first, first, and fourth place with a SUCRA of 91.7, 99.7, and 39.9%, respectively in increasing weaning success and SBT success and in prolonging ICU or LWU length of stay among four SBT strategies. The confidences in evidences were rated as low for most comparisons.Conclusion: ATC seems to be the optimal choice of predicting successful weaning from ventilator among critically ill patients. However, randomized controlled trials (RCTs) with high quality are needed to further establish these findings.

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

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

INTEGRATED USE OF BEDSIDE LUNG ULTRASOUND AND ECHOCARDIOGRAPHY AS AIDING PREDICTORS IN SUCCESSFUL WEANING PROCESS

Background: We hypothesized that bedside lung ultrasound (LUS) and echocardiography could be a predictor of postextubation distress by detecting a high lung aeration defect immediately before weaning by evidencing significant lung derecruitment during the spontaneous breathing trial (SBT). Objective: To evaluate the effectiveness of Lung Ultrasound (LUS) and Transthoracic Echocardiography (TTE) in predicting successful weaning of mechanically ventilated patients. Patients and Methods: This study was performed on 50 mechanically ventilated patients in general and respiratory ICU during the period from August 2019 to January 2021, at Bab-Al-Sha'reia University Hospital. Lung ultrasound and echocardiography were determined before and at the end of a 60-min spontaneous breathing trial (SBT) and 4 hrs. after extubation. To quantify lung aeration, a lung ultrasound score was calculated. Results: Forty-five patients had SBT success (90%) and 5 patients experienced SBT failure (10%), From those patients with SBT success, there were 16 patients (35.56%) had post extubation distress, and 29 patients (64.44%) had post extubation success. In patients who successfully passed the SBT, a lung ultrasound score ≤10 at the end of the SBT was highly predictive of postextubation success with a statistically significant difference (p value < 0.001). On the other hand, lung ultrasound score ≥18 at the end of the SBT was highly predictive of postextubation distress with a statistically significant difference (p value < 0.001). We found significant differences in E/A ratio 1.08 ± 0.2 in patients with spontaneous breathing trial success, and 1.6 ± 0.1 in patients with SBT failure with a statistical significant (p-value < 0.001). Conclusion: LUS and TTE during spontaneous breathing trial may accurately predict postextubation distress.

Association of Diaphragm Movement During Cough, as Assessed by Ultrasonography, With Extubation Outcome.

A cough peak flow (CPF) of < 60 L/min was associated with increased risk of extubation failure after a successful spontaneous breathing trial (SBT). Passive cephalic excursion of the diaphragm (PCED), measured by ultrasonography during cough expiration, was reported to predict CPF in healthy adults. We hypothesized that PCED, diaphragm peak velocity, or both during cough, as measured by ultrasonography, might predict CPF and extubation outcomes in mechanically ventilated patients. This study attempted to identify associations of diaphragm movement during cough, as assessed by ultrasonography with simultaneously measured CPF, and to determine predictive values of ultrasonographic indices for extubation outcomes after a successful SBT. In the study, 252 mechanically ventilated subjects with a successful SBT were enrolled in a prospective cohort study. Right hemidiaphragm passive cephalic excursion and peak velocity were measured by ultrasonography during voluntary cough expiration with maximum effort. CPF was measured simultaneously by ultrasonography. A multiple regression model adjusted for age and sex showed a significant association between PCED and CPF (P < .001, adjusted β coefficient 11.4, 95% CI 8.88-14.0, adjusted R2 = 0.287) and between diaphragm peak velocity and CPF (P < .001, adjusted β coefficient 1.71, 95% CI 1.91-2.24, adjusted R2 = 0.235). The areas under the curves of PCED, diaphragm peak velocity, and CPF for extubation failure were 0.791 (95% Cl 0.668-0.914), 0.587 (95% Cl 0.426-0.748), and 0.765 (95% Cl 0.609-0.922), respectively. PCED on ultrasonography was significantly associated with CPF and extubation failure after a successful SBT. Future studies should investigate if this method is applicable for determination of tracheostomy decannulation in stable patients in general wards.

Does diaphragm ultrasound improve the rapid shallow breathing index accuracy for predicting the success of weaning from mechanical ventilation?

BackgroundThis prospective study investigated whether taking into account diaphragmatic excursion (DE) measured by ultrasonography would improve the performance of the rapid shallow breathing index (RSBI) to predict extubation success or failure. ObjectivesThe aim of the study was to compare the new composite index named the rapid shallow diaphragmatic index (RSDI), and the RSBI measured during a spontaneous breathing trial regarding their ability to predict the need for re-intubation at 72 h. MethodsOne hundred mechanically ventilated patients underwent daily 30-min spontaneous breathing trials (SBTs) under pressure support ventilation of 6 cm H2O and end-expiratory pressure of 0 cm H2O until the SBT was considered successful and followed by extubation. The performances of RSBI (respiratory rate/tidal volume) and of the ratio RSBI/DE measured at 5 and 25 min of the successful SBT were compared in terms of area under the receiver operating characteristics curve (AUC), for predicting extubation success at 72 h. As secondary analysis, extubation and weaning success at 7 d were also considered. As exploratory analyses, predictive indices incorporating both clinical characteristics, the DE, and ultrasound diaphragm thickening fraction (DTF) were investigated. ResultsRSBI and RSBI/DE showed AUCs with 95% confidence intervals consistently extending below 0.50, either at the 5th (0.55 [0.36–0.74] and 0.55 [0.34–0.75], respectively) or at the 25th minute of SBT (0.49 [0.27–0.71] and 0.50 [0.29–0.68], respectively) for predicting weaning success at 72 h or at 7 d (5th min: 0.53 [0.37–0.70] and 0.54 [0.37–0.70], respectively; 25th min: 0.54 [0.37–0.71] and 0.55 [0.39–0.71], respectively). An exploratory index incorporating the accessory respiratory muscle activity, DE, DTF, and respiratory rate at 5th min of SBT showed AUCs for predicting extubation success at 7 d in the 78 patients with DTF measurement (0.77 [0.64–0.90]) that were significantly higher than that of the RSBI (P = 0.017) and RSBI/DE (P < 0.001) in the same respective populations. ConclusionsThe RSBI and the ratio RSBI/DE failed to predict weaning success when measured during an SBT performed under minimal pressure support. Predictive indices incorporating ultrasound DE and DTF may merit further investigation.

Discordances Between Factors Associated With Withholding Extubation and Extubation Failure After a Successful Spontaneous Breathing Trial.

To identify whether factors associated with withholding extubation in the ICU also predict the risk of extubation failure. Retrospective cohort study. Eight medical-surgical ICUs in Toronto. Adult patients receiving invasive mechanical ventilation, with a first successful spontaneous breathing trial within 28 days of initial ICU admission. None. The primary end point had three mutually exclusive levels, including: 1) withholding extubation after a successful spontaneous breathing trial, 2) extubation failure within 48 hours, and 3) successful extubation. Among 9,910 patients, 38% of patients were not extubated within 24 hours of their first successful spontaneous breathing trial. A total of 12.9% of patients who were promptly extubated failed within the next 48 hours. Several discrepancies were evident in the association of factors with risk of withholding extubation and extubation failure. Specifically, both age and female sex were associated with withholding extubation (odds ratio, 1.07; 95% CI, 1.03-1.11; and odds ratio, 1.13; 95% CI, 1.02-1.26, respectively) but not a higher risk of failed extubation (odds ratio, 0.99; 95% CI, 0.93-1.05; and odds ratio, 0.93; 95% CI, 0.77-1.11, respectively). Conversely, both acute cardiovascular conditions and intubation for hypoxemic respiratory failure were associated with a higher risk of failed extubation (odds ratio, 1.32; 95% CI, 1.06-1.66; and odds ratio, 1.46; 95% CI, 1.16-1.82, respectively) but not a higher odds of a withheld extubation attempt (odds ratio, 0.79; 95% CI, 0.68-0.91; and odds ratio, 1.07; 95% CI, 0.93-1.23, respectively). Several factors showed discordance between the decision to withhold extubation and the risk of extubation failure. This discordance may lead to longer duration of mechanical ventilation or higher reintubation rates. Improving the decision-making behind extubation may help to reduce both exposure to invasive mechanical ventilation and extubation failure.

Dyspnoea and respiratory muscle ultrasound to predict extubation failure.

This study investigated dyspnoea intensity and respiratory muscle ultrasound early after extubation to predict extubation failure. The study was conducted prospectively in two intensive care units in France and Canada. Patients intubated for at least 48 h were studied within 2 h after an extubation following a successful spontaneous breathing trial. Dyspnoea was evaluated by a dyspnoea visual analogue scale (Dyspnoea-VAS) ranging from 0 to 10 and the Intensive Care Respiratory Distress Observational Scale (IC-RDOS). The ultrasound thickening fraction of the parasternal intercostal and the diaphragm was measured; limb muscle strength was evaluated using the Medical Research Council (MRC) score (range 0-60). Extubation failure occurred in 21 out of 122 enrolled patients (17%). The median (interquartile range (IQR)) Dyspnoea-VAS and IC-RDOS were higher in patients with extubation failure versus success: 7 (4-9) versus 3 (1-5) (p<0.001) and 3.7 (1.8-5.8) versus 1.7 (1.5-2.1) (p<0.001), respectively. The median (IQR) ratio of parasternal intercostal muscle to diaphragm thickening fraction was significantly higher and MRC was lower in patients with extubation failure compared with extubation success: 0.9 (0.4-2.1) versus 0.3 (0.2-0.5) (p<0.001) and 45 (36-50) versus 52 (44-60) (p=0.012), respectively. The thickening fraction of the parasternal intercostal and its ratio to diaphragm thickening showed the highest area under the receiver operating characteristic curve (AUC) for an early prediction of extubation failure (0.81). AUCs of Dyspnoea-VAS and IC-RDOS reached 0.78 and 0.74, respectively. Respiratory muscle ultrasound and dyspnoea measured within 2 h after extubation predict subsequent extubation failure.