S2k-Guideline "Prolonged Weaning"

Role of multidrug-resistant bacteria in weaning from invasive mechanical ventilation

BACKGROUND

Although multidrug-resistant bacteria (MDR) are common in patients undergoing prolonged weaning, there is little data on their impact on weaning and patient outcomes.

METHODS

This is a retrospective analysis of consecutive patients who underwent prolonged weaning and were at a university weaning centre from January 2018 to December 2020. The influence of MDR colonisation and infection on weaning success (category 3a and 3b), successful prolonged weaning from invasive mechanical ventilation (IMV) with or without the need for non-invasive ventilation (NIV) compared with category 3c (weaning failure 3cI or death 3cII) was investigated. The pathogen groups considered were: multidrug-resistant gram-negative bacteria (MDRGN), methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus spp. (VRE).

RESULTS

A total of 206 patients were studied, of whom 91 (44.2%) showed evidence of MDR bacteria (32% VRE, 1.5% MRSA and 16% MDRGN), with 25 patients also meeting the criteria for MDR infection. 70.9% of the 206 patients were successfully weaned from IMV, 8.7% died. In 72.2% of cases, nosocomial pneumonia and other infections were the main cause of death. Patients with evidence of MDR (infection and colonisation) had a higher incidence of weaning failure than those without evidence of MDR (48% vs. 34.8% vs. 21.7%). In multivariate analyses, MDR infection (OR 4.9, p = 0.004) was an independent risk factor for weaning failure, along with male sex (OR 2.3, p = 0.025), Charlson Comorbidity Index (OR 1.2, p = 0.027), pH (OR 2.7, p < 0.001) and duration of IMV before admission (OR 1.01, p < 0.001). In addition, MDR infection was the only independent risk factor for death (category 3cII), (OR 6.66, p = 0.007).

CONCLUSION

Patients with MDR infection are significantly more likely to die during the weaning process. There is an urgent need to develop non-antibiotic approaches for the prevention and treatment of MDR infections as well as clinical research on antibiotic stewardship in prolonged weaning as well as in ICUs.

Serum cholinesterase as a new nutritional indicator for predicting weaning failure in patients

Aim

The objective of this study is to examine the correlation between patient serum cholinesterase (SCHE) concentration and weaning failure in the context of invasive mechanical ventilation (IMV), as well as to identify predictors of ventilator weaning failure. Additionally, this study investigates the potential relationship between SCHE and nutritional risk for developing more effective weaning strategies.

Method

A retrospective observational study was conducted. The sample was collected from 227 patients with IMV over 48 h who underwent SBT before weaning. Relevant experimental samples and data collection were analyzed at the time of patient admission and before the initiation of the SBT. The correlation between SCHE and weaning failure was determined by multifactorial logistic regression and propensity matching scores.

Results

Weaning was successful in 127 patients and failed in 100 patients. Depending on the difficulty of weaning, 55 of these patients had difficulty in weaning and 45 had long-term weaning. In the crude cohort, experimental data collected on the day of SBT showed that SCHE concentrations were higher in patients with successful weaning than in those with failed weaning (4,514 u/l vs. 3,190 u/l p < 0.01). The critical value for predicting weaning failure was SCHE 3,228 u/l (p < 0.01). Ventilator weaning failure was predicted by multifactorial logistic regression analysis of SCHE, heart rate, and PaO₂ before SBT, with SCHE predicting ventilator weaning failure (AUC 0.714; 95% CI 0.647-0.782) better than heart rate (AUC 0.618; 95% CI 0.545-0.690), PaO₂ (AUC 0.59; 95% CI 0.515-0.664). After propensity-matched scores, SCHE remained an independent predictor of weaning failure (p = 0.05). And the SCHE concentration was strongly correlated with the patient's weaning difficulties (p < 0.01). The Nutrition Risk in Critically Ill (NUTRIC) score was also significantly correlated with SCHE according to Spearman's correlation analysis (p < 0.01).

Conclusion

Our study revealed that the patients who experienced weaning failure exhibited lower SCHE values compared to those who successfully underwent weaning. Before spontaneous breathing trial (SBT), SCHE, heart rate, and PaO₂ were identified as independent predictors of weaning failure. Following propensity score matching (PSM), SCHE and heart rate remained independent predictors. Patients with SCHE levels below 3,228 u/l should undergo careful evaluation before weaning. Our findings suggest that malnutrition may be a contributing factor to weaning failure in patients.

Care practices for patients requiring mechanical ventilation more than seven days in Swedish intensive care units: A national survey

OBJECTIVE

To identify care practices in Swedish intensive care units specific to patients requiring mechanical ventilation for >7 days.

RESEARCH METHODOLOGY

We conducted a national cross-sectional survey inviting all adult Swedish ICUs (n = 79). Nurse managers were invited by email to complete a questionnaire by telephone. The questionnaire included seven domains: ventilator weaning, mobilisation, communication, nutrition, symptom assessment, psychosocial support and organisational characteristics.

RESULTS

We received responses from 77 units (response rate, 97%). Weaning protocols were available in 42 (55%) units, 52 (68%) used individualised weaning strategies and 50 (65%) involved physicians and nurses in collaborative decision making. In 48 units (62%), early mobilisation was prioritised using bed cycling but only 26 (34%) units had mobilisation protocols. Most of the intensive care units (74, 96%) had nutrition protocols but only 2 (3%) had dedicated dieticians. Delirium screening tools were available in 49 (64%) ICUs, 3 (4%) assessed anxiety and none assessed dyspnoea. Nineteen (25%) units employed a primary nursing model and 11 (14%) indicated person-centred care policies. Regular case conferences, including family participation, were held by 39 (51%) units.

CONCLUSION

We found that an individualised approach to ventilator weaning, decided by physicians and nurses in collaboration, was the predominant approach, although weaning protocols were available in some intensive care units. Most units prioritised early mobilisation, though few used protocols. Nutritional protocols were widely adopted, as few units had a dedicated dietician.

Weaning from Invasive Ventilation in Specialist Centers Following Primary Weaning Failure

BACKGROUND

Ever more patients are being treated with invasive ventilation in the outpatient setting. Most have no access to a structured weaning process in a specialized weaning center. The personal burden on the patients is heavy, and the costs for the health care system are high.

METHODS

61 patients who had been considered unfit for weaning were admitted to a weaning center. The primary endpoint was the number of patients who had been successfully weaned from the ventilator at six months. The comparison group consisted of health-insurance datasets derived from patients who were discharged from an acute hospital stay to receive invasive ventilation in the outpatient setting.

RESULTS

50 patients (82%; 95% confidence interval [70.5; 89.6]) were successfully weaned off of invasive ventilation in the weaning centers, 21 of them (34% [23.8; 47]) with the aid of non-invasive ventilation. The survival rate at 1 year was higher than in the group without invasive ventilation (45/50, or 90%, versus 6/11,or 55%); non-invasive ventilation was comparable in this respect to no ventilation at all. The identified risk factors for weaning failure included the presence of more than five comorbidities and a longer duration of invasive ventilation before transfer to a weaning center.

CONCLUSION

If patients with prolonged weaning are cared for in a certified weaning center before being discharged to receive invasive ventilation in the outpatient setting, the number of persons being invasively ventilated outside the hospital will be reduced and the affected persons will enjoy a higher survival rate. This would also spare nursing costs.

The spontaneous breathing trial is of low predictive value regarding spontaneous breathing ability in subjects with prolonged, unsuccessful weaning

Background

The spontaneous breathing trial (SBT) is a well-established diagnostic test for predicting extubation failure in intubated intensive care unit (ICU) patients. However, the SBT has not been evaluated in a specific cohort of tracheostomized patients in whom weaning is prolonged and ultimately unsuccessful.

Objective

The aim of the trial was to investigate the relevance of SBT failure criteria in chronic respiratory failure subjects undergoing long-term invasive home mechanical ventilation following tracheostomy and weaning failure.

Methods

Measurement of all established failure criteria including pneumotachygraphical assessment of the rapid shallow breathing index (RSBI) took place during an SBT. The decision to continue spontaneous breathing was based on failure criteria as well as the subjective willingness of the patient.

Results

Fifteen subjects with a median age of 58 years (interquartile range [IQR] 44–74) were studied; 10 with COPD, 4 with neuromuscular diseases and 1 with both. Twelve subjects met the SBT failure criteria within 30 min, but one third of these subjects were still able to continue with spontaneous breathing. In contrast, 3 subjects could not be weaned despite the SBT being successful. An increased RSBI was the most frequently observed SBT failure criterion (57% of all SBT). However, the SBT varied substantially in individual subjects who were able to sustain spontaneous breathing, despite having reached the cut-off for SBT failure.

Conclusion

The SBT was of low predictive value regarding spontaneous breathing ability in chronic respiratory failure subjects with prolonged, unsuccessful weaning.

Sepsis in mechanically ventilated patients with spinal cord injury: a retrospective analysis

Study Design

Retrospective analysis.

Objectives

Sepsis, one of the most frequent and life-threatening complications on intensive care units (ICUs), is associated with a need for mechanical ventilation (MV) as well as adverse respiratory outcomes in hospitalized individuals. However, it has poorly been investigated in patients with spinal cord injury (SCI); a population at high risk for pulmonary and infectious complications.

Setting

Spinal Cord Injury Center, Heidelberg University Hospital.

Methods

Over a 5-year period, 182 individuals with SCI requiring MV during their ICU stay were analyzed. Data assessment included demographics, medical characteristics, focus and causative pathogen of sepsis, length of stay, weaning outcomes, and mortality.

Results

Sepsis was recorded in 28 patients (15%), containing a subgroup of individuals suffering from infectious SCI and co-occurring primary sepsis with Staphylococcus aureus as the predominant microorganism. In most individuals, sepsis was found as secondary complication, which was associated with pulmonary foci, Gram-negative bacteria, and high mortality. More than 80% of individuals with secondary sepsis required induction of MV due to respiratory failure. Furthermore, respiratory failure was found to be independent of sepsis focus, spectrum of causative pathogens, SCI etiology, or severity of injury. Subsequent weaning from the respirator was prolonged in more than 90% with a high proportion of weaning failure.

Conclusions

Sepsis predominantly occurs as a secondary complication after SCI and is associated with detrimental outcomes. Although the lung is frequently affected as a failing organ, not all sepsis foci are pulmonary. Awareness of both actual sepsis focus and causative pathogen is central to initiate an adequate sepsis treatment.

Clinical evidence for respiratory insufficiency type II predicts weaning failure in long-term ventilated, tracheotomised patients: a retrospective analysis

Background

Patients who require a prolonged weaning process comprise a highly heterogeneous group of patients amongst whom the outcome differs significantly. The present study aimed to identify the factors that predict whether the outcome for prolonged weaning will be successful or unsuccessful.

Methods

Data from tracheotomised patients who underwent prolonged weaning on a specialised weaning unit were assessed retrospectively via an electronic and paper-bound patient chart. Factors for weaning success were analysed by univariate and multivariate analyses.

Results

Out of the 124 patients examined, 48.4% were successfully weaned (n = 60). Univariate analysis revealed that long-term home mechanical ventilation prior to current weaning episode; time between intubation and the first spontaneous breathing trial (SBT); time between intubation and the first SBT of less than 30 days; lower PaCO₂ prior to, and at the end of, the first SBT; and lower pH values at the end of the first SBT were predictors for successful weaning. Following multivariate analysis, the absence of home mechanical ventilation prior to admission, a maximum time period of 30 days between intubation and the first SBT, and a non-hypercapnic PaCO₂ value at the end of the first SBT were predictive of successful weaning.

Conclusions

The current analysis demonstrates that the evidence for respiratory insufficiency type II provided by clinical findings serves as a predictor of weaning failure.

Impact of multidrug-resistant bacteria on outcome in patients with prolonged weaning

Background

Pneumonia and septic pneumonic shock are the most common indications for long-term mechanical ventilation and prolonged weaning, independent of any comorbidities. Multidrug resistant (MDR) bacteria are emerging as a cause of pneumonia or occur as a consequence of antimicrobial therapy. The influence of MDR bacteria on outcomes in patients with prolonged weaning is unknown.

Methods

Patients treated in a specialized weaning unit of a university hospital between April 2013 and April 2016 were analyzed. Demographic data, clinical characteristics, length of stay (LOS) in the intensive care unit (ICU) and weaning unit, ventilator-free days and mortality rates were determined in prolonged weaning patients with versus without MDR bacteria (methicillin-resistant Staphylococcus aureus bacteria, [MRSA]; extended spectrum beta lactamase [ESBL]- and Gyrase-producing gram negative bacteria resistant to three of four antibiotic groups [3 MRGN]; panresistant Pseudomonas aeruginosa and other carbapenemase-producing gram-negative bacteria resistant to all four antibiotic groups [4 MRGN]). Weaning failure was defined as death or discharge with invasive ventilation.

Results

Of 666 patients treated in the weaning unit, 430 fulfilled the inclusion criteria and were included in the analysis. A total of 107 patients had isolates of MDR bacteria suspected as causative pathogens identified during the treatment process. Patients with MDR bacteria had higher SAPS II values at ICU admission and a significantly longer ICU LOS. Four MRGN P. aeruginosa and Acinetobacter baumanii were the most common MDR bacteria identified. Patients with versus without MDR bacteria had significantly higher arterial carbon dioxide levels at the time of weaning admission and a significantly lower rate of successful weaning (23% vs 31%, p < 0.05). Mortality rate on the weaning unit was 12.4% with no difference between the two patient groups. There were no significant differences between patient groups in secondary infections and ventilator-free days.

Conclusions

In patients with pneumonia or septic pneumonic shock undergoing prolonged weaning, infection with MDR bacteria may influence the weaning success rate but does not appear to impact on patient survival.

Quality of life and life satisfaction are severely impaired in patients with long-term invasive ventilation following ICU treatment and unsuccessful weaning

Background

Health-related quality of life (HRQL), life satisfaction, living conditions, patients’ attitudes towards life and death, expectations, beliefs and unmet needs are all poorly understood aspects associated with patients receiving invasive home mechanical ventilation (HMV) following ICU treatment and unsuccessful weaning. Therefore, the present study aimed to assess (1) HRQL, (2) life satisfaction and (3) patients’ perspectives on life and death associated with invasive HMV as the consequence of unsuccessful weaning.

Results

Patients undergoing invasive HMV with full technical supply and maximal patient care were screened over a 1-year period and assessed in their home environment. The study comprised the following: (1) detailed information on specific aspects of daily life, (2) self-evaluation of 23 specific daily life aspects, (3) HRQL assessment using the Severe Respiratory Insufficiency Questionnaire, (4) open interviews about the patient’s living situation, HRQL, unsolved problems, treatment options, dying and the concept of an afterlife. Out of 112 patients admitted to a specialized weaning centre, 50 were discharged with invasive HMV and 25 out of these (14 COPD and 11 neuromuscular patients) were ultimately enrolled. HRQL and life satisfaction were severely impaired, despite maximal patient care and full supply of technical aids. The most important areas of dissatisfaction identified were mobility, communication, social contact and care dependency. Importantly, 32% of patients would have elected to die in hindsight rather than receive invasive HMV.

Conclusions

Despite maximal patient care and a full supply of technical aids, both HRQL and life satisfaction are severely impaired in many invasive HMV patients who have failed prolonged weaning. These findings raise ethical concerns about the use of long-term invasive HMV following unsuccessful weaning.

Electronic supplementary material

The online version of this article (10.1186/s13613-018-0384-8) contains supplementary material, which is available to authorized users.

Home noninvasive ventilatory support for patients with chronic obstructive pulmonary disease: patient selection and perspectives

Long-term or home mechanical noninvasive ventilation (Home-NIV) has become a well-established form of therapy over the last few decades for chronic hypercapnic COPD patients in European countries. However, meta-analyses and clinical guidelines do not recommend Home-NIV for COPD patients on a routine basis. In particular, there is ongoing debate about Home-NIV in chronic hypercapnic COPD regarding the overall effects, the most favorable treatment strategy, the selection of eligible patients, and the time point at which it is prescribed. The current review focuses on specific aspects of patient selection and discusses the various scientific as well as clinical-guided perspectives on Home-NIV in patients suffering from chronic hypercapnic COPD. In addition, special attention will be given to the topic of ventilator settings and interfaces.

Electrical impedance tomography for predicting failure of spontaneous breathing trials in patients with prolonged weaning

Background

Spontaneous breathing trials (SBTs) on a T-piece can be difficult in patients with prolonged weaning because of remaining de-recruitment phenomena and/or insufficient ventilation. There is no clinically established method existent other than experience for estimating whether an SBT is most probably beneficial. Electrical impedance tomography (EIT) is a clinical useful online monitoring technique during mechanical ventilation, particularly because it enables analysis of effects of regional ventilation distribution. The aim of our observational study was to examine if EIT can predict whether patients with prolonged weaning will benefit from a planned SBT.

Methods

Thirty-one patients were examined. Blood gas analysis, vital parameter measurements, and EIT recordings were performed at three time points: (1) baseline with pressure support ventilation (PSV) (t0), (2) during a T-piece trial (t1), and (3) after resumption of PSV (t2). Calculation of EIT parameters was performed, including the impedance ratio (IR), the tidal variation of impedance (TIV), the changes in end-expiratory lung impedance (ΔEELI), the global inhomogeneity index (GI), and the regional ventilation delay (RVD) index with use of different thresholds of the percentage inspiration time (RVD40, RVD60, RVD80). The predictive power of the baseline GI with regard to clinical impairment of an SBT was analyzed by means of ROC curves. Clinical deterioration was assumed when tidal volume was decreased by at least 20 ml after the T-piece trial, measured at t2.

Results

Partial pressure of arterial oxygen significantly decreased at t1 (71 ± 15 mmHg) compared with t0 (85 ± 17 mmHg, p < 0.05) and t2 (82 ± 18 mmHg, p < 0.05). The IR trended toward higher values during t1. At t1, TIV and ΔEELI significantly decreased. The GI was significantly increased at t1 (t0 59.3 ± 46.1 vs t1 81.5 ± 62.5, p = 0.001), as were all RVD indexes. Assuming a GI cutoff value of >40, sensitivity of 85% and specificity of 50% were reached for predicting an increased future tidal volume.

Conclusions

EIT enables monitoring of regional ventilation distribution during SBTs and is suitable to estimate whether an SBT probably will be beneficial for an individual patient. Therefore, the application of EIT can support clinical decisions regarding patients in the phase of prolonged weaning.

Pneumologie

Die Pneumologie und Beatmungsmedizin gehört zur Basis der Intensivmedizin. Die Abklärung der Dyspnoe, das Management des Asthma bronchiale, der akuten COPD-Exazerbation und des akuten Lungenversagens (ARDS) bilden die Säulen dieses Kapitels. Im Rahmen der bettseitigen Abklärung der Dyspnoe gewinnt die Lungen- bzw. Thoraxsonographie zunehmend an Bedeutung.