Initial synchronized intermittent mandatory ventilation versus assist/control ventilation in treatment of moderate acute respiratory distress syndrome: a prospective randomized controlled trial

Postoperative recovery among head and neck cancer patients receiving microvascular free flap surgery with implementing nurse-protocolized targeted sedation: relationship of use of sedatives and mechanical ventilation to length of ICU stay

PURPOSE

Patients receiving microvascular free flap surgery are usually admitted to a high-dependency adult intensive care unit (ICU). Research is limited to investigate postoperative recovery among head and neck cancer patients in the ICU. This study aimed to evaluate a nursing-protocolized targeted sedation on postoperative recovery and to examine the relationship of demographic characteristics, use of sedation, mechanical ventilator to length of ICU stay in patients receiving microvascular free flap surgery for head and neck reconstruction.

METHODS

This retrospective study involves 125 ICU patients at a medical centre in Taiwan. Medical records were reviewed between 1 January 2015 and 31 December 2018 including surgery-related data, medications and sedations used, and ICU-related outcomes.

RESULTS

The mean length of ICU stay was 6.2 days (SD = 2.6), and the mean duration of mechanical ventilation was 4.7 days (SD = 2.3). The daily dosage of sedation used in patients who received microvascular free flap surgery was dramatically reduced since the postoperative day (POD) 7. Over 50% of patients switched to PS + SIMV ventilator mode on POD 4. Duration of sedation used (r = 0.331, p < 0.001), total dosage of sedation (r = 0.901, p < 0.001), clear consciousness (r =  - 0.517, p < 0.001), and duration on mechanical ventilator (r = 0.378, p < 0.001) are correlated with the length of ICU stay.

CONCLUSION

This study provides an understanding of the use of sedation, mechanical ventilator, and length of ICU stay to inform the continued education for clinicians.

The Effect of Switching from Volume-Controlled to Pressure-Controlled Ventilation on Respiratory Distress and Asynchrony Index Improvement among Mechanically Ventilated Adults

Background

It is important to synchrony the time, intensity, and respiratory signal of the phrenic nerve between the patient and the ventilator. This study aimed to evaluate the effect of switching from volume-controlled to pressure-controlled ventilation on respiratory distress and asynchrony index improvement.

Materials and Methods

In this randomized controlled clinical trial, 70 patients admitted to the intensive care unit under mechanical ventilation were included. Asynchronous evaluation was performed by examining the patient and evaluating and analyzing the graphic flow curve and ventilator pressure, which included trigger and flow asynchronous and asynchronous cycling. In the intervention group, the mode of ventilation was switched to PSIMV such that peak inspiratory pressures would be equivalent to positive end-expiratory pressure (PEEP) in the volume-controlled mode. Finally, again at 60, 75, and 90 min, information about the ventilator and the patient's symptoms, and arterial carbon dioxide levels were sent by arterial gas sample. The asynchronous index was also recorded in both groups.

Results

This study showed that the mean of variables such as height, ideal body weight, tidal volume, set rate; Sense, FiO₂, PEEP did not differ significantly between the two groups. The mean of asynchrony was significantly reduced in both control group (16.51 ± 3.35-14.51 ± 2.90; P < 0.001) and intervention group (18.26 ± 6.13-13.32 ± 5.53; P < 0.001).

Conclusion

Regardless of the type and severity of the disease, switching the ventilation mode from volume-controlled to pressure-controlled can improve patient adaptation to the ventilator, especially in cases with frequent asynchrony.

ARDS Clinical Practice Guideline 2021

Background

The joint committee of the Japanese Society of Intensive Care Medicine/Japanese Respiratory Society/Japanese Society of Respiratory Care Medicine on ARDS Clinical Practice Guideline has created and released the ARDS Clinical Practice Guideline 2021.

Methods

The 2016 edition of the Clinical Practice Guideline covered clinical questions (CQs) that targeted only adults, but the present guideline includes 15 CQs for children in addition to 46 CQs for adults. As with the previous edition, we used a systematic review method with the Grading of Recommendations Assessment Development and Evaluation (GRADE) system as well as a degree of recommendation determination method. We also conducted systematic reviews that used meta-analyses of diagnostic accuracy and network meta-analyses as a new method.

Results

Recommendations for adult patients with ARDS are described: we suggest against using serum C-reactive protein and procalcitonin levels to identify bacterial pneumonia as the underlying disease (GRADE 2D); we recommend limiting tidal volume to 4–8 mL/kg for mechanical ventilation (GRADE 1D); we recommend against managements targeting an excessively low SpO₂ (PaO₂) (GRADE 2D); we suggest against using transpulmonary pressure as a routine basis in positive end-expiratory pressure settings (GRADE 2B); we suggest implementing extracorporeal membrane oxygenation for those with severe ARDS (GRADE 2B); we suggest against using high-dose steroids (GRADE 2C); and we recommend using low-dose steroids (GRADE 1B). The recommendations for pediatric patients with ARDS are as follows: we suggest against using non-invasive respiratory support (non-invasive positive pressure ventilation/high-flow nasal cannula oxygen therapy) (GRADE 2D), we suggest placing pediatric patients with moderate ARDS in the prone position (GRADE 2D), we suggest against routinely implementing NO inhalation therapy (GRADE 2C), and we suggest against implementing daily sedation interruption for pediatric patients with respiratory failure (GRADE 2D).

Conclusions

This article is a translated summary of the full version of the ARDS Clinical Practice Guideline 2021 published in Japanese (URL: https://www.jsicm.org/publication/guideline.html). The original text, which was written for Japanese healthcare professionals, may include different perspectives from healthcare professionals of other countries.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40560-022-00615-6.

Patient-ventilator asynchrony, impact on clinical outcomes and effectiveness of interventions: a systematic review and meta-analysis

Background

Patient–ventilator asynchrony (PVA) is a common problem in patients undergoing invasive mechanical ventilation (MV) in the intensive care unit (ICU), and may accelerate lung injury and diaphragm mis-contraction. The impact of PVA on clinical outcomes has not been systematically evaluated. Effective interventions (except for closed-loop ventilation) for reducing PVA are not well established.

Methods

We performed a systematic review and meta-analysis to investigate the impact of PVA on clinical outcomes in patients undergoing MV (Part A) and the effectiveness of interventions for patients undergoing MV except for closed-loop ventilation (Part B). We searched the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, ClinicalTrials.gov, and WHO-ICTRP until August 2020. In Part A, we defined asynchrony index (AI) ≥ 10 or ineffective triggering index (ITI) ≥ 10 as high PVA. We compared patients having high PVA with those having low PVA.

Results

Eight studies in Part A and eight trials in Part B fulfilled the eligibility criteria. In Part A, five studies were related to the AI and three studies were related to the ITI. High PVA may be associated with longer duration of mechanical ventilation (mean difference, 5.16 days; 95% confidence interval [CI], 2.38 to 7.94; n = 8; certainty of evidence [CoE], low), higher ICU mortality (odds ratio [OR], 2.73; 95% CI 1.76 to 4.24; n = 6; CoE, low), and higher hospital mortality (OR, 1.94; 95% CI 1.14 to 3.30; n = 5; CoE, low). In Part B, interventions involving MV mode, tidal volume, and pressure-support level were associated with reduced PVA. Sedation protocol, sedation depth, and sedation with dexmedetomidine rather than propofol were also associated with reduced PVA.

Conclusions

PVA may be associated with longer MV duration, higher ICU mortality, and higher hospital mortality. Physicians may consider monitoring PVA and adjusting ventilator settings and sedatives to reduce PVA. Further studies with adjustment for confounding factors are warranted to determine the impact of PVA on clinical outcomes.

Trial registration protocols.io (URL: https://www.protocols.io/view/the-impact-of-patient-ventilator-asynchrony-in-adu-bsqtndwn, 08/27/2020).

Supplementary Information

The online version contains supplementary material available at 10.1186/s40560-021-00565-5.

Between-trial heterogeneity in ARDS research

Purpose

Most randomized controlled trials (RCTs) in patients with acute respiratory distress syndrome (ARDS) revealed indeterminate or conflicting study results. We aimed to systematically evaluate between-trial heterogeneity in reporting standards and trial outcome.

Methods

A systematic review of RCTs published between 2000 and 2019 was performed including adult ARDS patients receiving lung-protective ventilation. A random-effects meta-regression model was applied to quantify heterogeneity (non-random variability) and to evaluate trial and patient characteristics as sources of heterogeneity.

Results

In total, 67 RCTs were included. The 28-day control-group mortality rate ranged from 10 to 67% with large non-random heterogeneity (I² = 88%, p < 0.0001). Reported baseline patient characteristics explained some of the outcome heterogeneity, but only six trials (9%) reported all four independently predictive variables (mean age, mean lung injury score, mean plateau pressure and mean arterial pH). The 28-day control group mortality adjusted for patient characteristics (i.e. the residual heterogeneity) ranged from 18 to 45%. Trials with significant benefit in the primary outcome reported a higher control group mortality than trials with an indeterminate outcome or harm (mean 28-day control group mortality: 44% vs. 28%; p = 0.001).

Conclusion

Among ARDS RCTs in the lung-protective ventilation era, there was large variability in the description of baseline characteristics and significant unexplainable heterogeneity in 28-day control group mortality. These findings signify problems with the generalizability of ARDS research and underline the urgent need for standardized reporting of trial and baseline characteristics.

Supplementary Information

The online version of this article (10.1007/s00134-021-06370-w) contains supplementary material, which is available to authorized users.

Influence of ventilatory strategies on outcomes and length of hospital stay: assist-control and synchronized intermittent mandatory ventilation modes

The use of synchronized intermittent mandatory ventilation with pressure support ventilation (SIMV + PSV) mode has been discontinued. This study analyzed the association between medical outcomes related to the use of assist-control (A/C) and SIMV + PSV in an intensive care unit. In this observational and retrospective study, modes of ventilation and medical data were collected from electronic medical records for three consecutive years and were related to medical outcomes (mortality), duration of mechanical ventilation, length of hospital stay and the need for tracheostomy. Participants were divided into groups according to the modes of ventilation: A/C and SIMV + PSV. Statistical analyses were performed in the R environment. Alpha = 0.05. The using chi-square, Fisher's exact, Mann-Whitney and Kruskal-Wallis tests were used. 345 adult participants were included; 211/345 (61.16%) were males. Of the participants, 151/345 (43.77%) were on SIMV + PSV and 194/345 (56.23%) were on A/C. The comparative analysis between the modes of ventilation showed no significant differences in length of hospital stay (p = 0.675), duration of mechanical ventilation (p = 0.952), mortality (p = 0.241), failed extubation (p = 0.411) and the need for tracheostomy (p = 0.301). SIMV + PSV as a mode of ventilation showed similar statistical results to the A/C mode, when compared to analyzed medical outcomes.

Endocan, a Risk Factor for Developing Acute Respiratory Distress Syndrome among Severe Pneumonia Patients

Background

Severe pneumonia (SP) has been widely accepted as a major cause for acute respiratory distress syndrome (ARDS), and the development of ARDS is significantly associated with increased mortality. This study aimed to identify potential predictors for ARDS development in patients with SP.

Methods

Eligible SP patients at admission from January 2013 to June 2017 were prospectively enrolled, and ARDS development within hospital stay was identified. Risk factors for ARDS development in SP patients were analyzed by univariate and multivariate logistic regression analysis. The receiver operating characteristic (ROC) curve analysis with the area under the curve (AUC) was performed for the predictive value of endocan for ARDS development.

Results

A total of 145 SP patients were eventually enrolled into the final analysis, of which 37 developed ARDS during the hospital stay. Our final multivariate logistic regression analysis suggested plasma endocan expression as the only independent risk factor for ARDS development in SP patients (OR: 1.57, 95% CI: 1.14–2.25, P=0.021). ROC curve analysis of plasma endocan resulted in an AUC of 0.754, 95% CI of 0.642–0.866, a cutoff value of 11.6 ng/mL, a sensitivity of 78.7%, and a specificity of 70.3%, respectively (P < 0.01).

Conclusions

Endocan expression at ICU admission is a reliable predictive factor in predicting ARDS in patients with SP.

Modes of mechanical ventilation vary between hospitals and intensive care units within a university healthcare system: a retrospective observational study

Objective

As evidence-based guidance to aid clinicians with mechanical ventilation mode selection is scant, we sought to characterize the epidemiology thereof within a university healthcare system and hypothesized that nonconforming approaches could be readily identified. We conducted an exploratory retrospective observational database study of routinely recorded mechanical ventilation parameters between January 1, 2010 and December 31, 2016 from 12 intensive care units. Mode epoch count proportions were examined using Chi squared and Fisher exact tests as appropriate on an inter-unit basis with outlier detection for two test cases via post hoc pairwise analyses of a binomial regression model.

Results

Final analysis included 559,734 mode epoch values. Significant heterogeneity was demonstrated between individual units (P < 0.05 for all comparisons). One unit demonstrated heightened utilization of high-frequency oscillatory ventilation, and three units demonstrated frequent synchronized intermittent mandatory ventilation utilization. Assist control ventilation was the most commonly recorded mode (51%), followed by adaptive support ventilation (23.1%). Volume-controlled modes were about twice as common as pressure-controlled modes (64.4% versus 35.6%). Our methodology provides a means by which to characterize the epidemiology of mechanical ventilation approaches and identify nonconforming practices. The observed variability warrants further clinical study about contributors and the impact on relevant outcomes.

Electronic supplementary material

The online version of this article (10.1186/s13104-018-3534-z) contains supplementary material, which is available to authorized users.

Early identification of patients at risk for acute respiratory distress syndrome among severe pneumonia: a retrospective cohort study

Background

Severe pneumonia is the predominant cause for acute respiratory distress syndrome (ARDS). Identification of ARDS from patients with severe pneumonia remains a significant clinical problem due to the overlap of clinical presentations and symptoms. Early recognition of risks for ARDS from severe pneumonia is of great clinical value.

Methods

From April 2014 to December 2015, patients with severe pneumonia at admission were retrieved from the hospital database, of which ARDS developed within 7 days were further identified. We compared the demographic and clinical characteristics at admission between severe pneumonia patients with and without ARDS development, followed by analysis of potential predictors for ARDS development and mortality. Multivariate logistic regression and receiver operating characteristic (ROC) curves were performed to screen independent risk factors and identify their sensitivity in predicting ARDS development and prognosis.

Results

Compared with severe pneumonia without ARDS development, patients with ARDS development had shorter disease duration before admission, higher lung injury score (LIS), serum fibrinogen (FiB), and positive end-expiratory pressure (PEEP), lower Marshall score, sequential organ failure assessment score and proportion of cardiovascular and gastrointestinal diseases, but similar mortality. Serum FiB >5.15 g/L [adjusted odds ratio (OR) 1.893, 95% confidence interval (CI): 1.141-3.142, P=0.014] and PEEP >6.5 cmH₂O (adjusted OR 1.651, 95% CI: 1.218-2.237, P=0.001) were independent predictors for ARDS development with a sensitivity of 58.3% and 87.5%, respectively, and pH <7.35 (adjusted OR 0.832, 95% CI: 0.702-0.985, P=0.033) was an independent risk factor for ARDS mortality with a sensitivity of 95.2%.

Conclusions

ARDS development risk could be early recognized by PEEP >6.5 cmH₂O and serum FiB >5.15 g/L in severe pneumonia patients, and pH <7.35 is a reliable prognostic factor in predicting ARDS mortality risk.