Rapid Shallow Breathing Index Research Articles

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.

Ultrasonographic evaluation of diaphragm thickness and excursion: correlation with weaning success in trauma patients: prospective cohort study.

Prolonged mechanical ventilation (MV) subjects multiple trauma patients to ventilator-induced diaphragmatic dysfunction. There is limited evidence on the predictive role of diaphragm ultrasound (DUS) for weaning success in multiple trauma patients. Therefore, we evaluated Ultrasound of the diaphragm as a valuable indicator of weaning outcomes, in trauma patients. This prospective cohort study included 50 trauma patients from September 2018 to February 2019. DUS was performed twice: upon ICU admission and the first weaning attempt. The diagnostic accuracy of indexes was evaluated by ROC curves. The study included patients with a mean age of 35.4 ± 17.37, and 78% being male. The median injury severity score was 75 (42-75). The failure group exhibited significantly lower right diaphragmatic excursion (DE) compared to the success group (P = 0.006). In addition, the failure group experienced a significant decrease in both right and left DE from admission to the first attempt of weaning from MV (P < 0.001). Both groups showed a significant decrease in inspiratory and expiratory thickness on both sides during weaning from MV compared to the admission time (P < 0.001). The findings from the ROC analysis indicated that the Rapid shallow breathing index (RSBI) (Sensitivity = 91.67, Specificity = 100), respiratory rate (RR)/DE (Right: Sensitivity = 87.5, Specificity = 92.31), and RR/TF (Thickening Fraction) (Right: Sensitivity = 83.33, Specificity = 80.77) demonstrated high sensitivity and specificity in predicting weaning outcome. In the context of patients with multiple trauma, employing DUC and assessing diaphragmatic excursion, thickness, RR/DE index, RR/TF index, and RSBI can aid in determining successful ventilator weaning.

Analyzing key elements of breathing patterns, deriving remaining variables, and identifying cutoff values in individuals with chronic respiratory disease and healthy subjects

BackgroundPulmonary physiology encompasses intricate breathing patterns (BPs), characterized by breathing frequency (Bf), volumes, and flows. The complexities intensify in the presence of interstitial lung disease (ILD) and chronic obstructive pulmonary disease (COPD), especially during exercise. This study seeks to identify pivotal factors driving changes among these variables and establish cutoff values, comparing their efficacy in differentiating BPs to traditional methods, specifically a breathing reserve (BR) of 30% and a Bf of 50 bpm. MethodsScreening 267 subjects revealed 23 with ILD, 126 with COPD, 33 healthy individuals, and the exclusion of 85 subjects. Lung function tests and ramp-pattern cardiopulmonary exercise testing (CPET) were conducted, identifying crucial BP elements. Changes were compared between groups at peak exercise. The area under the receiver operating characteristic curve (AUC) analysis determined cutoff values. ResultsInspiratory time (TI) remained constant at peak exercise for all subjects (two-group comparisons, all p=NS). Given known differences in expiratory time (TE) and tidal volume (VT) among ILD, COPD, and healthy states, constant TI could infer patterns for Bf, total breathing cycle time (TTOT=60/Bf), I:E ratio, inspiratory duty cycle (IDC, TI/TTOT), rapid shallow breathing index (Bf/VT), tidal inspiratory and expiratory flows (VT/TI and VT/TE), and minute ventilation (V̇E=Bf×VT) across conditions. These inferences aligned with measurements, with potential type II errors causing inconsistencies. RSBI of 23 bpm/L and VT/TI of 104 L/min may differentiate ILD from control, while V̇E of 54 L/min, BR of 30%, and VT/TE of 108 may differentiate COPD from control. BR of 21%, TE of 0.99 s, and IDC of .45 may differentiate ILD from COPD. The algorithm outperformed traditional methods (AUC 0.84–0.91 versus 0.59–0.90). ConclusionThe quasi-fixed TI, in conjunction with TE and VT, proves effective in inferring time-related variables of BPs. The findings have the potential to significantly enhance medical education in interpreting cardiopulmonary exercise testing. Moreover, the study introduces a novel algorithm for distinguishing BPs among individuals with ILD, COPD, and those who are healthy.

УЛЬТРАЗВУКОВОЕ ИССЛЕДОВАНИЕ ДИАФРАГМЫ КАК ПРЕДИКТОР УСПЕШНОГО ОТЛУЧЕНИЯ ПАЦИЕНТОВ ОТ АППАРАТА ИСКУССТВЕННОЙ ВЕНТИЛЯЦИИ ЛЕГКИХ

The relevance of the survey is linked with the persistent problem of weaning patients who have been on mechanical ventilation for a long time. The objective. To conduct a literature analysis in order to summarize the results of modern researches devoted to the study of sonographic parameters that allow estimation of diaphragmatic functions for predicting successful weaning of patients from artificial lung ventilation. Material and methods. In total 33 Russian-language and English-language sources were analyzed. Results. The following ultrasound parameters of the diaphragm were analyzed in detail: diaphragm excursion, diaphragm thickening fraction, diaphragmatic rapid shallow breathing index, and the time to peak inspiratory amplitude of the diaphragm. Conclusions. The ability to timely diagnose diaphragm dysfunction using ultrasound minimizes the risk of respiratory and cardiac failure. Currently there are methods of the diaphragm muscle stimulation to improve the recovery of lost functions.

Risk factors for postoperative adverse airway events in patients with primary oral cancer undergoing reconstruction without prophylactic tracheostomy

ObjectiveTo identify risk factors associated with adverse airway events (AAEs) in primary oral cancer patients undergoing tumor ablation followed by free tissue transfer without prophylactic tracheostomy. MethodsWe retrospectively collected primary oral cancer patients who underwent tumor ablation surgery following free-tissue transfer without prophylactic tracheostomy during February 2017 to June 2019 in Chang Gung Memorial Hospital, Linkou Medical Center, Taiwan. 379 patients were included. Data were analysed from 2020 to 2021. Demographics, comorbidities, intraoperative variables and postoperative respiration profile were obtained from the medical record. Main outcome was postoperative AAEs, including requirement of endotracheal intubation after extubation and tracheostomy after prolonged intubation. ResultsOf the 379 patients, postoperative AAEs happened in 29 patients (7.6 %). In reintubation group, patients were older with more diabetes mellitus, hypertension and cerebrovascular disease. These patients had lower preoperative hemoglobin, creatinine, and albumin level with more intraoperative blood transfusion. In postoperative respiration profile, rapid shallow breathing index (RSBI) and PaO2/FiO2 (PF) ratio were poorer. On multivariate analysis, patient's age, tumor location, and cross-midline segmental mandibulectomy and a lower PF ratio were independent risk factors for postoperative AAEs. ConclusionsIn head and neck cancer patients that underwent tumor ablation followed by free tissue transfer without prophylactic tracheostomy, patient's age, tumor location, cross-midline segmental mandibulectomy and P/F ratio are associated with postoperative AAEs.

Predicting extubation in patients with traumatic cervical spinal cord injury using the diaphragm electrical activity during a single maximal maneuver

BackgroundThe unsuccessful extubation in patients with traumatic cervical spinal cord injuries (CSCI) may result from impairment diaphragm function and monitoring of diaphragm electrical activity (EAdi) can be informative in guiding extubation. We aimed to evaluate whether the change of EAdi during a single maximal maneuver can predict extubation outcomes in CSCI patients.MethodsThis is a retrospective study of CSCI patients requiring mechanical ventilation in the ICU of a tertiary hospital. A single maximal maneuver was performed by asking each patient to inhale with maximum strength during the first spontaneous breathing trial (SBT). The baseline (during SBT before maximal maneuver), maximum (during the single maximal maneuver), and the increase of EAdi (ΔEAdi, equal to the difference between baseline and maximal) were measured. The primary outcome was extubation success, defined as no reintubation after the first extubation and no tracheostomy before any extubation during the ICU stay.ResultsAmong 107 patients enrolled, 50 (46.7%) were extubated successfully at the first SBT. Baseline EAdi, maximum EAdi, and ΔEAdi were significantly higher, and the rapid shallow breathing index was lower in patients who were extubated successfully than in those who failed. By multivariable logistic analysis, ΔEAdi was independently associated with successful extubation (OR 2.03, 95% CI 1.52–3.17). ΔEAdi demonstrated high diagnostic accuracy in predicting extubation success with an AUROC 0.978 (95% CI 0.941–0.995), and the cut-off value was 7.0 μV.ConclusionsThe increase of EAdi from baseline SBT during a single maximal maneuver is associated with successful extubation and can help guide extubation in CSCI patients.

ASSESSMENT OF THE RATE OF CHANGE IN THE RAPID SHALLOW BREATHING INDEX AND ITS IMPACT ON EXTUBATION OUTCOMES IN MECHANICALLY VENTILATED PATIENTS

Mechanical ventilation is a crucial intervention in critical care, but weaning and extubation can be complex. Extubation failure poses significant risks, including increased morbidity and mortality. The Rapid Shallow Breathing Index (RSBI) has been explored to predict extubation outcomes. Still, recent research suggests that assessing the rate of change of RSBI over time (ΔRSBI) could enhance prediction accuracy. In this prospective observational study, we analyzed data from patients with respiratory failure, including those with airway diseases and those without documented respiratory conditions. RSBI was measured at the 5th and 120th minutes of spontaneous breathing trials (SBT), and the ΔRSBI was calculated. Patients were categorized into extubation failure and success groups based on their post-extubation outcomes. Receiver-operating characteristic (ROC) curves were generated to determine optimal RSBI thresholds for predicting extubation failure. Out of 119 patients, 23 were excluded due to intolerance to the 120-minute SBT. The remaining 96 patients were divided into normal and airway groups. In the overall analysis, ΔRSBI had an AUC of 0.943, with a threshold of 26% ΔRSBI predicting extubation failure (sensitivity 96%, specificity 91%, overall accuracy 89%). RSBI 120 had an AUC of 0.837, with an optimal threshold of 71 (sensitivity 86%, specificity 78%, overall accuracy 82%). In the normal group, ΔRSBI (AUC 0.785) with a threshold of 24% (sensitivity 86%, specificity 92%, overall accuracy 88%) outperformed RSBI-120 (AUC 0.931) with a threshold of 70 (sensitivity 86%, specificity 91%, overall accuracy 86%). In the airway group, ΔRSBI (AUC 0.893) with a threshold of 26% ΔRSBI (sensitivity 88%, specificity 84%, overall accuracy 88%) and RSBI 120 (AUC 0.863) with a threshold of 76 (sensitivity 88%, specificity 84%, overall accuracy 84%) showed strong predictive capabilities.&#x0D; Assessing the rate of change of RSBI during a 120-minute SBT offers superior predictive value for extubation outcomes compared to a single RSBI measurement. This approach is particularly valuable in patients with airway diseases. Accurate extubation prediction can reduce reintubation rates and associated complications, ultimately improving patient care.

Acupuncture for ventilator-dependent patients at a hospital-based respiratory care center: A randomized controlled trial

BackgroundIn intensive care units, mechanical ventilation is an important therapy to help patients with dyspnea. However, long-term ventilator dependence would consume huge medical resources and increase the risk of morbidity and mortality. The aim of the study was to examine the efficacy of the acupuncture combined with western medical care on ventilator parameters in ventilator-dependent patients. MethodsIn this clinical trial, 80 ventilator-dependent patients aged 20 to 80 years old were randomly assigned to acupuncture group and control group in the respiratory care center (RCC) of Changhua Christian Hospital. Besides regular medical care and therapy, participants in the acupuncture group received acupuncture therapy at the same 17 acu-points for 20 minutes once a day, a total of 12 sessions. The ventilator parameters were recorded to evaluate the respiratory efficiency for all participants. The primary outcome was rapid shallow breathing index (RSBI), and secondary outcomes were respiratory rate (RR), tidal volume (TV) and ventilation per minute (MV), ResultsThough there was no significant difference in the parameter between the acupuncture group and the control group, we found the trend of decreasing RSBI in the acupuncture group. In subgroup analyses, the mean of RSBI significantly decreased 16.02 (with the SD in 60.84) in acupuncture group, while it increased 17.84 (with the SD in 39.38) in control group (p=0.036) after 12 sessions. ConclusionAcupuncture treatment can improve breathing ability of patients with respirator dependence in respiratory care center.

41 Analysis of an Emergency Department Extubation Protocol Using Readiness-To-Wean and Rapid Shallow Breathing Index

41 Analysis of an Emergency Department Extubation Protocol Using Readiness-To-Wean and Rapid Shallow Breathing Index

Rate of Change of Rapid Shallow Breathing Index and Extubation Outcome in Mechanically Ventilated Patients.

Rapid shallow breathing index (RSBI) has been widely used as a predictor of extubation outcome in mechanically ventilated patients. We hypothesize that the rate of change of RSBI between the beginning and end of a 120-minute spontaneous breathing trial (SBT) could be a better predictor of extubation outcome than a single RSBI measured at the end of SBT in mechanically ventilated patients. Methodology. In this prospective observational study, we enrolled 193 patients who met the inclusion criteria, of whom 33 patients were unable to tolerate a 120-minute SBT and were excluded from the study. The study population consisted of 160 patients, categorized into three subgroups: patients with normal lung (no reported history of respiratory diseases), patients with airway disease, and patients with parenchymal disease who completed 120 minutes of SBT on low levels of pressure support ventilation. RSBI was obtained from the ventilator display at the 5th and the 120th minutes of SBT. The rate of change of RSBI (RSBI 5-120) was calculated as (RSBI 2-RSBI 1)/RSBI 1 × 100. Receiver-operating characteristic (ROC) curves were plotted for RSBI 5-120 and RSBI 120 in all patients and among the three subgroups (normal group, airway group, and parenchymal group) to compare the superiority of their best thresholds in predicting extubation failure. The RSBI 5-120 threshold for extubation failure in the entire patient group was 23% with an overall accuracy of 88% (AUC = 0.933, sensitivity = 91%, and specificity = 86%) and the threshold of RSBI 120 for extubation failure in the entire patient group was 70 breaths/min/L with an overall accuracy of 82% (AUC = 0.899, sensitivity = 85%, and specificity = 81%). In patients in the normal lung group, the threshold of RSBI 5-120 was 22%, with an overall accuracy of 89% (AUC = 0.892, sensitivity = 87.5%, and specificity = 90%), and the RSBI 120 threshold was 70 breaths/min/L, with an overall accuracy of 89% (AUC = 0.956, sensitivity = 88%, and specificity = 90%). The RSBI 5-120 threshold in patients with airway disease was 25% with an accuracy of 86% (AUC = 0.892, sensitivity = 85%, and specificity = 86%) and the threshold of RSBI 120 was 73 breaths/min/L with an accuracy of 83% (AUC = 0.874, sensitivity = 85%, and specificity = 82%). In patients in the parenchymal disease group, the threshold of RSBI 5-120 was 24%, with an accuracy of 90% (AUC = 0.966, sensitivity = 92%, and specificity = 89%) and RSBI 120 threshold was 71 breaths/min/L, which was 88% accurate (AUC = 0.893, sensitivity = 85%, and specificity = 89%). The rate of change of RSBI between the 5th and 120th minutes was moderately more accurate than the single value of RSBI measured at the 120th minute in predicting extubation outcome.

Is diaphragm ultrasound better than rapid shallow breathing index for predicting weaning in critically ill elderly patients?

Prolonged weaning is associated with worse clinical outcomes in elderly patients. Beside traditional rapid shallow breathing index (RSBI), diaphragm ultrasound is a promising technique to evaluate the weaning process. We aimed to perform diaphragm ultrasonography for predicting the weaning process and its relation with frailty in the critically ill elderly population. We enrolled thirthy-two patients over 65 years of age who were mechanically ventilated for at least 48 hours. Thickness of diaphragm and excursion were evaluated within 48 h of intubation and during spontaneous breathing trial (SBT). Clinical parameters, frailty, diaphragm ultrasound results were compared according to the weaning status. Mean age (standard deviation) was 79.3 ± 7.9 years, and 18 (56.3%) patients were classified as weaning failure. Diaphragmatic excursion during SBT was the only statistically significant parameter associated with weaning failure [2.37 cm (0.67) vs 1.43 cm (0.15), p= 0.0359]. There was no statistically significant difference regarding RSBI between the groups [70.5 (46) vs 127.5 (80), p= 0.09]. Baseline thickness of diaphragm and excursion at SBT were moderately correlated with frailty. Ultrasound can be used to show diaphragm dysfunction in the elderly frail population, and a multifactorial approach to the extubation process may include ultrasound instead of using traditional RSBI alone.

2022 Year in Review: Ventilator Liberation.

Mechanical ventilation is ubiquitous in critical care, and duration of ventilator liberation is variable and multifactorial. While ICU survival has increased over the last two decades, positive-pressure ventilation can cause harm to patients. Weaning and discontinuation of ventilatory support is the first step in ventilator liberation. Clinicians have a wealth of evidence-based literature at their disposal; however, more high-quality research is needed to describe outcomes. Additionally, this knowledge must be distilled into evidence-based practice and applied at the bedside. A proliferation of research on the subject of ventilator liberation has been published in the last 12 months. Whereas some authors have reconsidered the value of applying the rapid shallow breathing index in weaning protocols, others have begun to investigate new indices to predict liberation outcomes. New tools such as diaphragmatic ultrasonography have begun to appear in the literature as a tool for outcome prediction. A number of systematic reviews with both meta-analysis and network meta-analysis that synthesize the literature on ventilator liberation have also been published in the last year. This review describes changes in performance, monitoring of spontaneous breathing trials, and evaluations of successful ventilator liberation.

Static Respiratory System Compliance as a Predictor of Extubation Failure in Patients with Acute Respiratory Failure.

Ventilator weaning protocols rely in part on objective indices to best predict extubation failure in the critically ill. We investigated static respiratory system compliance (RC) as a predictor of extubation failure, in comparison to extubation readiness using rapid shallow breathing index (RSBI). This was a cross-sectional, multi-institutional study of mechanically ventilated patients admitted between 12/01/2017 and 12/01/2019. All patients older than 18years with a documented spontaneous breathing trial and extubation trial were included. RC and RSBI were calculated prior to the extubation trial. The primary outcome was extubation failure-defined as need for reintubation within 72h from time of extubation. Of the 2263 patients, 55.8% were males with a mean age of 68 years. The population consisted mostly of Caucasians (73%) and African Americans (20.4%). 274 (12.1%) patients required reintubation within 72h. On multivariate logistic regression after adjusting for age, sex, body mass index (BMI), admission Sequential Organ Failure Assessment (SOFA) score, number of ventilator days, and the P/F ratio on the day of extubation, RC remained the strongest predictor for extubation failure at 24h (aOR 1.45; 95% CI 1.00-2.10) and 72h (aOR 1.58; 95% CI 1.15-2.17). There was no significant association between RSBI and extubation failure at 24 (aOR 1.00; 95% CI 0.99-1.01) or at 72h (aOR 1.00; 95% CI 0.99-1.01). RC measured on the day of extubation is a promising physiological discriminant to potentially risk stratify patients with acute respiratory failure for extubation readiness. We recommend further validation studies in prospective cohorts.

Ventilatory ratio as a predictor for extubation failure in critical ill patients based on MIMIC-IV database (from 2008 to 2019).

Background: The predictive ability of the ventilatory ratio (VR) for extubation failure risk in critically ill patients on mechanical ventilation is unclear. This study aims to examine the predictive ability of VR for extubation failure risk. Methods: This retrospective study was based on the MIMIC-IV database. The MIMIC-IV database consists of the clinical information of patients who were admitted to the intensive care unit at the Beth Israel Deaconess Medical Center between 2008 and 2019. With extubation failure as the primary outcome and in-hospital mortality as the secondary outcome, we assessed the predictive value of VR 4hours before extubation using a multivariate logistic regression model. Results: Of 3,569 ventilated patients who were included, the rate of extubation-failure was 12.7% and the median Sequential Organ Failure Assessment (SOFA) score was 6 before extubation. Increased VR, elevated heart rate, greater positive end-expiratory pressure, higher blood urea nitrogen level, higher platelet count, greater SOFA score, decreased pH, decreased tidal volume, presence of chronic pulmonary disease, paraplegia, and metastatic solid tumor were independent predictors for extubation failure. A threshold of 1.595 of VR was associated with prolonged intensive care unit length of stay, higher risk of mortality and extubation failure. The area under the receiver operating characteristic curve (ROC) for VR was 0.669 [0.635-0.703], which was significantly larger than the rapid shallow breathing index [0.510 (0.476-0.545)] and the partial pressure of oxygen to the fraction of inspired oxygen [0.586 (0.551-0.621)]. Conclusion: VR 4hours before extubation was associated with extubation failure, mortality, and prolonged length of stay in the intensive care unit. VR provides good predictive performance for extubation failure (measured by ROC) than the rapid shallow breathing index. Further prospective studies are warranted to confirm these findings.

Work of Breathing During Proportional Assist Ventilation as a Predictor of Extubation Failure.

Despite decades of research on predictors of extubation success, use of ventilatory support after extubation is common and 10-20% of patients require re-intubation. Proportional assist ventilation (PAV) mode automatically calculates estimated total work of breathing (total WOB). Here, we assessed the performance of total WOB to predict extubation failure in invasively ventilated subjects. This prospective observational study was conducted in 6 adult ICUs at an academic medical center. We enrolled intubated subjects who successfully completed a spontaneous breathing trial, had a rapid shallow breathing index < 105 breaths/min/L, and were deemed ready for extubation by the primary team. Total WOB values were recorded at the end of a 30-min PAV trial. Extubation failure was defined as any respiratory support and/or re-intubation within 72 h of extubation. We compared total WOB scores between groups and performance of total WOB for predicting extubation failure with receiver operating characteristic curves. Of 61 subjects enrolled, 9.8% (n = 6) required re-intubation, and 50.8% (n = 31) required any respiratory support within 72 h of extubation. Median total WOB at 30 min on PAV was 0.9 J/L (interquartile range 0.7-1.3 J/L). Total WOB was significantly different between subjects who failed or were successfully extubated (median 1.1 J/L vs 0.7 J/L, P = .004). The area under the curve was 0.71 [95% CI 0.58-0.85] for predicting any requirement of respiratory support and 0.85 [95% CI 0.69-1.00] for predicting re-intubation alone within 72 h of extubation. Total WOB cutoff values maximizing sensitivity and specificity equally were 1.0 J/L for any respiratory support (positive predictive value [PPV] 70.0%, negative predictive value [NPV] 67.7%) and 1.3 J/L for re-intubation (PPV 26.3%, NPV 97.6%). The discriminative performance of a PAV-derived total WOB value to predict extubation failure was good, indicating total WOB may represent an adjunctive tool for assessing extubation readiness. However, these results should be interpreted as preliminary, with specific thresholds of PAV-derived total WOB requiring further investigation in a large multi-center study.

Investigating the differences in nutritional status between successfully weaned and unsuccessfully weaned respirator patients

Long-term respirator users admitted to intensive care units need to be transferred to a respiratory care center (RCC) for weaning. It may cause malnutrition in critical care patients, which may manifest as a reduction in respiratory muscle mass, lower ventilatory capacity, and decreased respiratory tolerance. This study aimed to assess that if the patients’ nutritional status were improved, it could help RCC patients to wean from respirators. All participants were recruited from the RCC of a medical foundation in the city and Taipei Tzu Chi Hospital. The indicators include serum albumin level, respirator detachment index, maximum inspiratory pressure (PImax), rapid shallow breathing index, and body composition measurements. We recorded the length of hospital stay, mortality, and RCW (respiratory care ward) referral rate for these participants and analyzed the differences in relevant research indicators between those who were and weren’t weaned off. 43 of 62 patients were weaned from respirators, while 19 failed. The resuscitation rate was 54.8%. Patients with respirator weaning had a lower number of RCC admission days (23.1 ± 11.1 days) than respirator-dependent patients (35.6 ± 7.8 days, P < 0.05). The PImax of successfully weaned patients had a greater reduction (− 27.09 ± 9.7 cmH2O) than unsuccessful ones (− 21.4 ± 10.2 cmH2O, P < 0.05). The Acute Physiology and Chronic Health Evaluation II (APACHE II) scores of successfully weaned patients (15.8 ± 5.0) were lower than those who were not (20.4 ± 8.4, P < 0.05). There was no significant difference in serum albumin levels between the two groups. In the successfully weaned patients, the serum albumin concentration was increased from 2.2 ± 0.3 to 2.5 ± 0.4 mg/dL, P < 0.05. Improved nutritional status can help RCC patients to wean from respirators.

Reversing Neuromuscular Blockade without Nerve Stimulator Guidance in a Postsurgical ICU-An Observational Study.

We aimed to determine if not using residual neuromuscular blockade (RNB) analysis to guide neuromuscular blockade reversal administration in the postsurgical ICU resulted in consequences related to residual weakness. This single-center, prospective study evaluated 104 patients arriving in a postcardiac surgical ICU. After demonstrating spontaneous movement and T > 35.5 °C, all patients underwent RNB evaluation, and neostigmine/glycopyrrolate was then administered. When patients later demonstrated an adequate Rapid Shallow Breathing Index, negative inspiratory force generation, and arterial blood gas values with minimal mechanical ventilatory support, RNB evaluation was repeated in 94 of the 104 patients, and all patients were extubated. Though RNB evaluation was performed, patients were extubated without considering these results. Eleven of one hundred four patients had not achieved a Train-of-Four (TOF) count of four prior to receiving neostigmine. Twenty of ninety-four patients demonstrated a TOF ratio ≤ 90% prior to extubation. Three patients received unplanned postextubation adjunct respiratory support-one for obvious respiratory weakness, one for pain-related splinting compounding baseline disordered breathing but without obvious benefit from BiPAP, and one for a new issue requiring surgery. Residual neuromuscular weakness may have been unrecognized before extubation in 1 of 104 patients administered neostigmine without RNB analysis. ICU-level care may mitigate consequences in such cases.

PO-02-016 PHYSIOLOGIC SIGNALS FROM CRT DEVICES ARE INDICATIVE OF CRT RESPONSE IN SMART-MSP STUDY

Cardiac resynchronization therapy (CRT) is a well-established treatment for some heart failure patients with reduced ejection fraction, but a subset of these patients does not respond to CRT. Multi-site pacing (MSP) is proposed to improve clinical response to CRT, but it is unclear which CRT subset would benefit from MSP. Physiologic sensor data from CRT devices may provide insights into this question. To determine whether device based physiologic parameters are indicative of CRT response/non-response and thus identify potential candidates for MSP. SMART-MSP study evaluated 6-month CRT response, defined by improved Clinical Composite Score, in patients with CRT defibrillators (CRT-D). Device parameters considered for this analysis included third (S3) and first (S1) heart sounds, thoracic impedance (ITTI), respiration rate, rapid shallow breathing index (RSBI), activity, and the multi-sensor HeartLogic index. From a randomly selected 60% development set of patients (183 CRT responders and 40 non-responders) with at least 150 days of data, the following statistical measures were calculated for each parameter based on the first 60- and 150-day epoch after CRT-D implant: mean (μ), standard deviation (σ) and change from first 30-day mean to last 30-day mean (Δ). To evaluate the effect of each measure on CRT response, odds ratios were calculated and tested for significance via univariable and multivariable logistic regression. The 60-day analysis (Fig 1A) shows that increases in σ60 for S3, S3/S1, RSBI, respiration rate, and HeartLogic index as well as μ60 for RSBI were significantly associated with reduced odds of CRT response in the univariable model. The only signal to survive multivariate elimination was respiration rate σ60. The 150-day analysis (Fig 1B) shows the same indications and that increases in μ150 for RSBI and HeartLogic index were associated with reduced odds while increases in μ150 and Δ150 for activity were associated with increased odds of CRT response. Both respiration rate σ150 and activity Δ150 survived multivariate elimination. Multiple device-based physiologic parameters significantly differed between CRT responders versus non-responders in the SMART-MSP study. 60-day results indicate that there is potential for device-based parameters to identify patients who may benefit from switching to MSP sooner. However, while useful parameters are apparent early on (60-day window), more parameters become significant over a longer follow-up (150 days).

ASSESSMENT OF PATIENTS READINESS FOR WEANING FROM THE RESPIRATOR AFTER MECHANICAL LUNG VENTILATION

Introduction. Approximately 20% of patients on mechanical lung ventilation (MLA) experience weaning difficulties. It is recommended to evaluate objective clinical criteria used to predict a patient's readiness of weaning from a respirator. Randomized trials have shown the effectiveness and safety of the spontaneous breathing test (SBT) with inspiratory pressure support as a weaning method. Currently, there are many predictors of ventilator weaning, including both clinical and sonographic criteria, such as rapid shallow breathing index (RSBI), diaphragm thickening fraction (DTf), and Diaphragmatic excursion (DE).&#x0D; Case description. Patient K., 87 years old, has a history of 3 acute ischemic strokes with signs of vascular dementia according to relatives. 3 weeks ago, she hit her head at home and lost consciousness. She was hospitalized in a medical institution, after drainage of subdural hematomas, she was under analgosedation. 26 hours after tracheal intubation, in the presence of clinical criteria, a SBT was performed with calculation of RSBI, DTf and DE. After evaluating the predictors of weaning from the respirator, a decision was made to extubate the patient. After weaning from the respirator, the general condition is satisfactory.&#x0D; Conclusions. Assessment of predictors of successful ventilator weaning is relevant in elderly patients with dementia, when assessment of mental status is difficult and the use of objective indicators helps in decision-making regarding ventilator weaning.

Pendelluft as a predictor of weaning in critically ill patients: An observational cohort study.

Objective: Weaning failure is associated with adverse clinical outcomes. This study aimed to evaluate the accuracy of pendelluft during the spontaneous breathing trials (SBT) as a predictor of weaning outcome of patients with mechanical ventilation. Methods: An observational cohort study included 60 critically ill patients who were eligible for extubation. Pendelluft and electrical activity of the diaphragm (Edi) were monitored at baseline and every 10minutes for the first 30min of SBT denoted as T0, T1, T2, and T3. The pendelluft was measured using electrical impedance tomography (EIT), and Edi parameters were collected by Edi catheter. Patients were followed up after extubation and were divided into success group and failure group. Pendelluft, Edi parameters, respiratory parameters, and clinical outcomes such as intensive care units (ICU) stay, mortality, and 28-day ventilator-free days were compared between the two groups. Receiver operating characteristic (ROC) curves were constructed to evaluate the ability of pendelluft to predict weaning outcome. Results: Fifty patients (50/60) were successfully weaned from the machine and 10 (10/60) failed, with weaning failure rate of 16.7%. Respiratory parameters such as rapid shallow breathing index (RSBI), respiratory rate (RR) and Edi parameters such as maximum value of Edi (Edimax), Edi variation between a maximum and minimum(ΔEdi) in the failure group were higher than those in the success group. The ICU stay and the 28-day ventilator-free days in the failure group were significantly longer than those in the success group. The 28-day mortality rate was higher in the failure group. The pendelluft mainly occurred in the early stage of SBT. Ventral pendelluft and total pendelluft in the failure group were higher than those in the success group at T1. Edimax and ΔEdi were positively correlated with pendelluft. The area under ROC curve (AUC) showed moderate predictive ability for ventral pendelluft in predicting weaning failure at T1 (AUC 0.76, 95% CI 0.58-0.94, cut-off value > 3% global tidal variation). Conclusion: Pendelluft is one of the factors leading to weaning failure, which may be related to diaphragm function. Measuring pendelluft volume maybe helpful to predict weaning.