Extravascular lung water in patients with severe sepsis: a prospective cohort study

Pulmonary Vascular Permeability and Extravascular Lung Water Index in Patients with Liver Cirrhosis and Septic Shock

Backgrounds and Aims: Patients with cirrhosis are susceptible to sepsis and septic shock. Cirrhotic patients also have increased capillary permeability and are prone to developing volume overload. Patients with septic shock may have an enhanced pulmonary vascular permeability index (PVPI) and extravascular lung water index (EVLWI), both of which are associated with an unfavorable prognosis. It is plausible that pre-existing hyperpermeability may deteriorate when cirrhotic patients develop septic shock. However, it remains unknown whether PVPI and EVLWI can predict the prognosis of cirrhotic patients with septic shock. Pulse Indicator Continuous Cardiac Output (PiCCO) is an established tool to measure PVPI and EVLWI. Therefore, we conducted this retrospective study to investigate the prognostic significance of PVPI and EVLWI in cirrhotic patients with septic shock using PiCCO monitoring. Methods: We included 83 patients with liver cirrhosis and septic shock. EVLW indexed to actual body weight (aEVLWI), EVLW indexed to predicted body weight (pEVLWI), PVPI, disease severity scores, and other biomarkers were analyzed. We collected the PiCCO data on the first 2 days. Results: The overall 28-day mortality was 43.4%. The values of PVPI, aEVLWI, and pEVLWI on day 2 (PVPID2, aEVLWID2, EVLWID2) were significantly higher in non-survivors. The discriminating power of PVPID2 and EVLWID2 to predict 28-day mortality was tested using the area under a ROC curve. The areas under ROC curves (mean ± SEM) were 0.713 ± 0.061 and 0.650 ± 0.063 for PVPID2 and pEVLWID2. In the multivariate analysis, PVPID2, bilirubin, and lactate were independent factors which predicted 28-day mortality. Conclusions: Higher levels of PVPID2 and pEVLWID2 are associated with higher 28-day mortality rates in cirrhotic patients with septic shock. PVPI and pEVLWI may be useful to guide fluid management in this clinical setting.

Extravascular lung water levels are associated with mortality: a systematic review and meta-analysis

Background

The prognostic value of extravascular lung water (EVLW) measured by transpulmonary thermodilution (TPTD) in critically ill patients is debated. We performed a systematic review and meta-analysis of studies assessing the effects of TPTD-estimated EVLW on mortality in critically ill patients.

Methods

Cohort studies published in English from Embase, MEDLINE, and the Cochrane Database of Systematic Reviews from 1960 to 1 June 2021 were systematically searched. From eligible studies, the values of the odds ratio (OR) of EVLW as a risk factor for mortality, and the value of EVLW in survivors and non-survivors were extracted. Pooled OR were calculated from available studies. Mean differences and standard deviation of the EVLW between survivors and non-survivors were calculated. A random effects model was computed on the weighted mean differences across the two groups to estimate the pooled size effect. Subgroup analyses were performed to explore the possible sources of heterogeneity.

Results

Of the 18 studies included (1296 patients), OR could be extracted from 11 studies including 905 patients (464 survivors vs. 441 non-survivors), and 17 studies reported EVLW values of survivors and non-survivors, including 1246 patients (680 survivors vs. 566 non-survivors). The pooled OR of EVLW for mortality from eleven studies was 1.69 (95% confidence interval (CI) [1.22; 2.34], p < 0.0015). EVLW was significantly lower in survivors than non-survivors, with a mean difference of −4.97 mL/kg (95% CI [−6.54; −3.41], p < 0.001). The results regarding OR and mean differences were consistent in subgroup analyses.

Conclusions

The value of EVLW measured by TPTD is associated with mortality in critically ill patients and is significantly higher in non-survivors than in survivors. This finding may also be interpreted as an indirect confirmation of the reliability of TPTD for estimating EVLW at the bedside. Nevertheless, our results should be considered cautiously due to the high risk of bias of many studies included in the meta-analysis and the low rating of certainty of evidence.

Trial registration the study protocol was prospectively registered on PROSPERO: CRD42019126985.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-022-04061-6.

Update on the use of ultrasound in the diagnosis and monitoring of the critical patient

Hemodynamic and respiratory complications are the main causes of morbidity and mortality in in critical care units (CCU). Imaging techniques are a key tool in differential diagnosis and treatment. In the last decade, ultrasound has shown great potential for bedside diagnosis of respiratory disease, as well as for the hemodynamic assessment of critically ill patients. Ultrasound has proven to be a useful guide for identifying the type of shock, estimating cardiac output, guiding fluid therapy and vasoactive drugs, providing security in the performance of percutaneous techniques (thoracentesis, pericardiocentesis, evacuation of abscesses/hematomas), detecting dynamically in real time pulmonary atelectasis and its response to alveolar recruitment maneuvers, and predicting weaning failure from mechanical ventilation. Due to its dynamic nature, simple learning curve and absence of ionizing radiation, it has been incorporated as an essential tool in daily clinical practice in CCUs. The objective of this review is to offer a global vision of the role of ultrasound and its applications in the critically ill patient.

The Association Between Extravascular Lung Water and Critical Care Outcomes Following Bilateral Lung Transplantation

Primary graft dysfunction (PGD) is a form of acute respiratory failure that complicates 30% of bilateral lung transplants. Higher grades of PGD correlate with higher severity of respiratory failure and unfavorable outcomes. Immediate PGD determination posttransplant‚ however, is not always predictive of PGD over subsequent days or intensive care unit outcomes. We aimed to evaluate whether extravascular lung water index (ELWI) measured immediately post bilateral lung transplant was associated with higher severity of PGD at 72 h and duration of mechanical ventilation.

Evaluation of the association between extravascular lung water and prognosis of sepsis: A protocol of systematic review

BACKGROUND

The purpose of this study is to explore the association between extravascular lung water (EVLW) and prognosis of sepsis (PS).

METHODS

We will carry out comprehensive literature search in electronic databases (PUBMED/MEDLINE, EMBASE, CENTRAL, WorldSciNet, PsycINFO, Allied and Complementary Medicine Database, CBM, and CNKI) and additional sources. All electronic databases will be searched from their initial to the present without language restrictions. Case-controlled studies reporting the association between EVLW and PS will be evaluated for inclusion. Outcomes of interest will include mortality rate, extravascular lung water index, pulmonary vascular permeability index, blood lactate clearance, oxygenation index, blood gas analysis, PaO2/FiO2, cardiac output index, global end diastolic volume index, intrathoracic blood volume index, systemic resistance index, acute physiology and chronic health scoring system II, and infection-related organ failure scoring system. Study quality will be evaluated using Newcastle-Ottawa Tool, and statistical analysis will be performed utilizing RevMan 5.4 software.

RESULTS

This study will summarize the most recent evidence to investigate the association between EVLW and PS.

CONCLUSIONS

The results of this study will provide an exhaustive view of the association between EVLW and PS.

STUDY REGISTRATION OSF

osf.io/vhnxw.

B-Lines Scores Derived From Lung Ultrasound Provide Accurate Prediction of Extravascular Lung Water Index: An Observational Study in Critically Ill Patients

Introduction:

Visualization of B-lines via lung ultrasound provides a non-invasive estimation of pulmonary hydration. Extravascular lung water index (EVLWI) and pulmonary vascular permeability index (PVPI) assessed by transpulmonary thermodilution (TPTD) represent the most validated parameters of lung water and alveolocapillary permeability, but measurement is invasive and expensive. This study aimed to compare the correlations of B-lines scores from extensive 28-sector and simplified 4-sector chest scan with EVLWI and PVPI derived from TPTD in the setting of intensive care unit (primary endpoint).

Methods:

We performed scoring of 28-sector and 4-sector B-Lines in 50 critically ill patients. TPTD was carried out with the PiCCO-2-device (Pulsion Medical Systems SE, Maquet Getinge Group). Median time exposure for ultrasound procedure was 12 minutes for 28-sector and 4 minutes for 4-sector scan.

Results:

Primarily, we found close correlations of 28-sector as well as 4-sector B-Lines scores with EVLWI (R² = 0.895 vs. R² = 0.880) and PVPI (R² = 0.760 vs. R² = 0.742). Both B-lines scores showed high accuracy to identify patients with specific levels of EVLWI and PVPI. The extensive 28-sector B-lines score revealed a moderate advantage compared to simplified 4-sector scan in detecting a normal EVLWI ≤ 7 (28-sector scan: sensitivity = 81.8%, specificity = 94.9%, AUC = 0.939 versus 4-sector scan: sensitivity = 81.8%, specificity = 82.1%, AUC = 0.902). Both protocols were approximately equivalent in prediction of lung edema with EVLWI ≥ 10 (28-sector scan: sensitivity = 88.9%, specificity = 95.7%, AUC = 0.977 versus 4-sector scan: sensitivity = 81.5%, specificity = 91.3%, AUC = 0.958) or severe pulmonary edema with EVLWI ≥ 15 (28-sector scan: sensitivity = 91.7%, specificity = 97.4%, AUC = 0.995 versus 4-sector scan: sensitivity = 91.7%, specificity = 92.1%, AUC = 0.978). As secondary endpoints, our evaluations resulted in significant associations of 28-sector as well as simplified 4-sector B-Lines score with parameters of respiratory function.

Conclusion:

Both B-line protocols provide accurate non-invasive evaluation of lung water in critically ill patients. The 28-sector scan offers a marginal advantage in prediction of pulmonary edema, but needs substantially more time than 4-sector scan.

Apoptotic cell therapy for cytokine storm associated with acute severe sepsis

Sepsis has no proven pharmacologic treatment other than appropriate antibiotic agents, fluids, vasopressors as needed, and possibly corticosteroids. It is generally initiated mainly by the simultaneous recognition by various components of the innate immune system of either pathogen-associated molecular patterns (PAMPs) or damage-associated molecular patterns (DAMPs). In the current study, we employed the murine cecal ligation and puncture (CLP) model for sepsis to evaluate the effect of post-CLP infusion of apoptotic cells (Allocetra-OTS) on a CLP severe sepsis model. Cardiovascular evaluation, acute kidney injury (AKI), acute liver injury (ALI), and hematological and metabolic function were evaluated. Cytokine and chemokine profiles were measured by Multiplex ELISA and mitochondrial function, and glycolysis by Seahorse. The Murine Sepsis Score (MSS) was used for disease severity definition. CLP mice had low blood pressure, poor cardiac output, and lung dysfunction, as well as AKI, ALI, and thrombocytopenia, which correlated with the MSS and corresponded to a cytokine/chemokine storm. Apoptotic cell administration markedly improved the cytokine and chemokine storm and restored the impaired mitochondrial and glycolytic function in white blood cells leading to increased survival, from 6 to 60% (P < 0.0001), together with a significant improvement in organ dysfunction. We conclude that the deleterious immune response in CLP-induced sepsis can be successfully modified by apoptotic cell infusion.

Transpulmonary thermodilution detects rapid and reversible increases in lung water induced by positive end-expiratory pressure in acute respiratory distress syndrome

PURPOSE

It has been suggested that, by recruiting lung regions and enlarging the distribution volume of the cold indicator, increasing the positive end-expiratory pressure (PEEP) may lead to an artefactual overestimation of extravascular lung water (EVLW) by transpulmonary thermodilution (TPTD).

METHODS

In 60 ARDS patients, we measured EVLW (PiCCO2 device) at a PEEP level set to reach a plateau pressure of 30 cmH₂O (HighPEEP_start) and 15 and 45 min after decreasing PEEP to 5 cmH₂O (LowPEEP_15' and LowPEEP_45', respectively). Then, we increased PEEP back to the baseline level (HighPEEP_end). Between HighPEEP_start and LowPEEP_15', we estimated the degree of lung derecruitment either by measuring changes in the compliance of the respiratory system (Crs) in the whole population, or by measuring the lung derecruited volume in 30 patients. We defined patients with a large derecruitment from the other ones as patients in whom the Crs changes and the measured derecruited volume were larger than the median of these variables observed in the whole population.

RESULTS

Reducing PEEP from HighPEEP_start (14 ± 2 cmH₂O) to LowPEEP_15' significantly decreased EVLW from 20 ± 4 to 18 ± 4 mL/kg, central venous pressure (CVP) from 15 ± 4 to 12 ± 4 mmHg, the arterial oxygen tension over inspired oxygen fraction (PaO₂/FiO₂) ratio from 184 ± 76 to 150 ± 69 mmHg and lung volume by 144 [68-420] mL. The EVLW decrease was similar in "large derecruiters" and the other patients. When PEEP was re-increased to HighPEEP_end, CVP, PaO₂/FiO₂ and EVLW significantly re-increased. At linear mixed effect model, EVLW changes were significantly determined only by changes in PEEP and CVP (p < 0.001 and p = 0.03, respectively, n = 60). When the same analysis was performed by estimating recruitment according to lung volume changes (n = 30), CVP remained significantly associated to the changes in EVLW (p < 0.001).

CONCLUSIONS

In ARDS patients, changing the PEEP level induced parallel, small and reversible changes in EVLW. These changes were not due to an artefact of the TPTD technique and were likely due to the PEEP-induced changes in CVP, which is the backward pressure of the lung lymphatic drainage. Trial registration ID RCB: 2015-A01654-45. Registered 23 October 2015.

Critical hemodynamic therapy oriented resuscitation helping reduce lung water production and improve survival

BACKGROUND

Increased extravascular lung water (EVLW) in shock is common in the critically ill patients. This study aimed to explore the effect of cardiac output (CO) on EVLW and its relevant influence on prognosis.

METHODS

The hemodynamic data of 428 patients with pulse-indicated continuous CO catheterization from Department of Critical Care Medicine, Peking Union Medical College Hospital were retrospectively collected and analyzed. The patients were assigned to acute respiratory distress syndrome group, cardiogenic shock group, septic shock group, and combined shock (cardiogenic and septic) group according to their symptoms. Information on 28-day mortality and renal function was also collected.

RESULTS

The CO and EVLW index (EVLWI) in the cardiogenic and combined shock groups were lower than those in the other groups (acute respiratory distress syndrome group vs. cardiogenic shock group vs. septic shock group vs. combined shock group: CO, 5.1 [4.0, 6.2] vs. 4.7 [4.0, 5.7] vs. 5.5 [4.3, 6.7] vs. 4.6 [3.5, 5.7] at 0 to 24 h, P = 0.009; 4.6 [3.8, 5.6] vs. 4.8 [4.1, 5.7] vs. 5.3 [4.4, 6.5] vs. 4.5 [3.8, 5.3] at 24 to 48 h, P = 0.048; 4.5 [4.1, 5.4] vs. 4.8 [3.8, 5.5] vs. 5.3 [4.0, 6.4] vs. 4.0 [3.2, 5.4] at 48 to 72 h, P = 0.006; EVLWI, 11.4 [8.7, 19.1] vs. 7.9 [6.6, 10.0] vs. 8.8 [7.4, 11.0] vs. 8.2 [6.7, 11.3] at 0 to 24 h, P < 0.001; 11.8 [7.7, 17.2] vs. 7.8 [6.3, 10.2] vs. 8.7 [6.6, 12.2] vs. 8.0 [6.6, 11.1] at 24 to 48 h, P < 0.001; and 11.3 [7.7, 18.7] vs. 7.5 [6.3, 10.0] vs. 8.8 [6.3, 12.2] vs. 8.4 [6.4, 11.2] at 48 to 72 h, P < 0.001. The trend of the EVLWI in the septic shock group was higher than that in the cardiogenic shock group (P < 0.05). Moreover, there existed some difference in the pulmonary vascular permeability index among the cardiogenic shock group, the septic shock group, and the combined shock group, without statistical significance (P > 0.05). In addition, there was no significant difference in tissue perfusion or renal function among the four groups during the observation period (P > 0.05). However, the cardiogenic shock group had a higher 28-day survival rate than the other three groups [log rank (Mantel-Cox) = 31.169, P < 0.001].

CONCLUSION

Tissue-aimed lower CO could reduce the EVLWI and achieve a better prognosis.

Development of Noninvasive in Vivo Approach to Assess Vascular Permeability in Inflammation Using Fluorescence Imaging

INTRODUCTION

In vivo fluorescence imaging can quantify vascular permeability without requiring sacrifice of animals. However, use of this noninvasive approach for vascular permeability assessment in remote organ injury caused by systemic inflammatory disease has not been reported.

METHODS

Evans blue (EB) and Genhance 750 fluorescent dye were mixed and injected into mice. The lung as a remote organ and the footpad as a noninvasive observational site were assessed in a cecal ligation and puncture (CLP)-induced systemic inflammation mouse model and compared with sham and hydrocortisone pretreated (CLP + HC) mouse models. Extraction of EB in harvested tissues was assessed as a conventional indicator of vascular permeability. Fluorescent intensities in the footpad or harvested lung were assessed and their correlation was analyzed to investigate this novel, noninvasive approach for estimation of lung vascular permeability.

RESULTS

Fluorescent intensity in the footpad and harvested lung in the CLP group was significantly higher than in the other groups (footpad, sham vs. CLP, P < 0.0001; CLP vs. CLP + HC, P = 0.0004; sham vs. CLP + HC, P = 0.058; lung, sham vs. CLP, P < 0.0001; CLP vs. CLP + HC, P < 0.0001; sham vs. CLP + HC, P = 0.060). The fluorescent intensity in the footpad was strongly correlated with that in the lung (r = 0.95).

CONCLUSIONS

This fluorescent technique may be useful for vascular permeability assessment based on EB quantification. Footpad fluorescent intensity was strongly correlated with that in the lung, and may be a suitable indicator in noninvasive estimation of lung vascular permeability.

Measurement of extravascular lung water to diagnose severe reperfusion lung injury following pulmonary endarterectomy: a prospective cohort clinical validation study

The measurement of extravascular lung water is a relatively new technology which has not yet been well validated as a clinically useful tool. We studied its utility in patients undergoing pulmonary endarterectomy as they frequently suffer reperfusion lung injury and associated oedematous lungs. Such patients are therefore ideal for evaluating this new monitor. We performed a prospective observational cohort study during which extravascular lung water index measurements were taken before and immediately after surgery and postoperatively in intensive care. Data were analysed for 57 patients; 21 patients (37%) experienced severe reperfusion lung injury. The first extravascular lung water index measurement after cardiopulmonary bypass failed to predict severe reperfusion lung injury, area under the receiver operating characteristic curve 0.59 (95%CI 0.44–0.74). On intensive care, extravascular lung water index correlated most strongly at 36 h, area under the receiver operating characteristic curve 0.90 (95%CI 0.80–1.00). Peri‐operative extravascular lung water index is not a useful measure to predict severe reperfusion lung injury after pulmonary endarterectomy, however, it does allow monitoring and measurement during the postoperative period. This study implies that extravascular lung water index can be used to directly assess pulmonary fluid overload and that monitoring patients by measuring extravascular lung water index during their intensive care stay is useful and correlates with their clinical course. This may allow directed, pre‐empted therapy to attenuate the effects and improve patient outcomes and should prompt further studies.

Assessing Extravascular Lung Water With Ultrasound: A Tool to Individualize Fluid Management?

Aggressive fluid resuscitation has become standard of care for hypotensive patients with sepsis. However, sepsis is a syndrome that occurs in patients with diverse underlying physiology and a one-size-fits-all approach to fluid administration seems misguided. To individualize fluid management, several methods to assess fluid responsiveness have been validated, but even in fluid responsive patients, fluid administration may still be harmful and lead to pulmonary edema. Hence, to individualize fluid management, in addition to fluid responsiveness, fluid tolerance needs to be assessed. This article examines whether lung ultrasound can be useful to detect excess extravascular lung water (EVLW) and thus assess fluid tolerance. The physiology of EVLW and the principles of lung ultrasound are briefly described. Articles examining the correlation between EVLW and lung ultrasound findings in various clinical settings are carefully reviewed. Overall, lung ultrasound has been found to be an excellent tool to detect EVLW, but large outcome studies investigating lung ultrasound-guided fluid management are still lacking.

Positive End-expiratory Pressure Ventilation Increases Extravascular Lung Water Due to a Decrease in Lung Lymph Flow

Positive end-expiratory pressure (PEEP) is used to improve gas exchange, increase functional residual capacity, recruit air spaces, and decrease pulmonary shunt in patients suffering from respiratory failure. The effect of PEEP on extravascular lung water (EVLW), however, is still not fully understood. This study was designed as a prospective laboratory experiment to evaluate the effects of PEEP on EVLW and pulmonary lymph flow (QL) under physiologic conditions.

Twelve adult sheep were operatively prepared to measure haemodynamics of the systemic and pulmonary circulation, and to assess EVLW. In addition, the lung lymphatic duct was cannulated and a tracheostomy performed. The animals were then mechanically ventilated in the awake-state without end-expiratory pressure (PEEP 0). After a two-hour baseline period, PEEP was increased to 10 cmH2O for the duration of two hours, and then reduced back to 0 cmH2O. Cardiopulmonary variables, QL, and arterial blood gases were recorded intermittently; EVLW was determined two hours after each change in PEEP.

The increase in PEEP resulted in a decrease in QL (7±1 vs 5±1 ml/h) and an increase in EVLW (498±40 vs 630±58 ml; P<0.05 each) without affecting cardiac output. As PEEP was decreased back to baseline, QL increased significantly (5±1 vs 10±2 ml/h), whereas EVLW returned back to baseline.

This study suggests that institution of PEEP produces a reversible increase in EVLW that is linked to a decrease in QL.

A Novel Porcine Model of Septic Shock Induced by Acute Respiratory Distress Syndrome due to Methicillin-resistant Staphylococcus aureus

Background:

Sepsis is one of the main causes of mortality in critically ill patients following progression to septic shock. To investigate the pathophysiologic changes of sepsis, we developed a novel porcine model of septic shock induced by acute respiratory distress syndrome (ARDS) due to methicillin-resistant Staphylococcus aureus (MRSA) pneumonia.

Methods:

Twenty-six male Landraces (Lvyuanweiye, Beijing, China) weighing 30 ± 2 kg were divided into four groups: sham group (SH; n = 5); cotton smoke inhalation group (SM; n = 6); MRSA pneumonia group (MR; n = 6); and septic shock group with cotton smoke inhalation + MRSA pneumonia (SS; n = 9). Extensive hemodynamics, oxygen dynamics, and lung function were monitored for 24 h following the injury or until death. Tissues were collected, and histopathology evaluations were carried out.

Results:

Blood cultures from 6 of 9 animals in the SS group were positive for MRSA. Two hours following the injury, decreased mean arterial blood pressure (60–70 mmHg) and cardiac index (<2 L·min⁻¹·m⁻²) were observed in the animals in the SS group, while systemic vascular resistance index was increased. The hemodynamic characteristics of septic shock were only observed in the SS group but not significant in the other groups. The PO₂/FiO₂ in the SM and SS groups decreased to 300 and 100, respectively. In the SS group, extravascular lung water index increased to 20 ml/kg, whereas thoracopulmonary compliance decreased to 10 ml/H₂O after injury. Deterioration of pulmonary function in the SS group was more serious than the SM and MR groups. Severe lung injury in the SS group was confirmed by the histopathology evaluations. The lung injury confirmed by high-resolution thin-section computed tomography and histopathology in the SS group was more serious than those of other groups.

Conclusions:

In the present study, we developed a novel porcine model of septic shock induced by ARDS due to severe MRSA pneumonia with characteristic hyperdynamic and hypodynamic phases in 24 h, which mimicked the hemodynamic changing of septic shock in human.

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2016 (J-SSCG 2016)

BACKGROUND AND PURPOSE

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2016 (J-SSCG 2016), a Japanese-specific set of clinical practice guidelines for sepsis and septic shock created jointly by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine, was first released in February 2017 and published in the Journal of JSICM, [2017; Volume 24 (supplement 2)] 10.3918/jsicm.24S0001 and Journal of Japanese Association for Acute Medicine [2017; Volume 28, (supplement 1)] http://onlinelibrary.wiley.com/doi/10.1002/jja2.2017.28.issue-S1/issuetoc.This abridged English edition of the J-SSCG 2016 was produced with permission from the Japanese Association of Acute Medicine and the Japanese Society for Intensive Care Medicine.

METHODS

Members of the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine were selected and organized into 19 committee members and 52 working group members. The guidelines were prepared in accordance with the Medical Information Network Distribution Service (Minds) creation procedures. The Academic Guidelines Promotion Team was organized to oversee and provide academic support to the respective activities allocated to each Guideline Creation Team. To improve quality assurance and workflow transparency, a mutual peer review system was established, and discussions within each team were open to the public. Public comments were collected once after the initial formulation of a clinical question (CQ) and twice during the review of the final draft. Recommendations were determined to have been adopted after obtaining support from a two-thirds (> 66.6%) majority vote of each of the 19 committee members.

RESULTS

A total of 87 CQs were selected among 19 clinical areas, including pediatric topics and several other important areas not covered in the first edition of the Japanese guidelines (J-SSCG 2012). The approval rate obtained through committee voting, in addition to ratings of the strengths of the recommendation, and its supporting evidence were also added to each recommendation statement. We conducted meta-analyses for 29 CQs. Thirty-seven CQs contained recommendations in the form of an expert consensus due to insufficient evidence. No recommendations were provided for five CQs.

CONCLUSIONS

Based on the evidence gathered, we were able to formulate Japanese-specific clinical practice guidelines that are tailored to the Japanese context in a highly transparent manner. These guidelines can easily be used not only by specialists, but also by non-specialists, general clinicians, nurses, pharmacists, clinical engineers, and other healthcare professionals.

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2016 (J-SSCG 2016)

Background and Purpose

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2016 (J-SSCG 2016), a Japanese-specific set of clinical practice guidelines for sepsis and septic shock created jointly by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine, was first released in February 2017 in Japanese. An English-language version of these guidelines was created based on the contents of the original Japanese-language version.

Methods

Members of the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine were selected and organized into 19 committee members and 52 working group members. The guidelines were prepared in accordance with the Medical Information Network Distribution Service (Minds) creation procedures. The Academic Guidelines Promotion Team was organized to oversee and provide academic support to the respective activities allocated to each Guideline Creation Team. To improve quality assurance and workflow transparency, a mutual peer review system was established, and discussions within each team were open to the public. Public comments were collected once after the initial formulation of a clinical question (CQ), and twice during the review of the final draft. Recommendations were determined to have been adopted after obtaining support from a two-thirds (>66.6%) majority vote of each of the 19 committee members.

Results

A total of 87 CQs were selected among 19 clinical areas, including pediatric topics and several other important areas not covered in the first edition of the Japanese guidelines (J-SSCG 2012). The approval rate obtained through committee voting, in addition to ratings of the strengths of the recommendation and its supporting evidence were also added to each recommendation statement. We conducted meta-analyses for 29 CQs. Thirty seven CQs contained recommendations in the form of an expert consensus due to insufficient evidence. No recommendations were provided for 5 CQs.

Conclusions

Based on the evidence gathered, we were able to formulate Japanese-specific clinical practice guidelines that are tailored to the Japanese context in a highly transparent manner. These guidelines can easily be used not only by specialists, but also by non-specialists, general clinicians, nurses, pharmacists, clinical engineers, and other healthcare professionals.

Pulmonary ultrasound scoring system for intubated critically ill patients and its association with clinical metrics and mortality: A prospective cohort study

PURPOSE

Pulmonary ultrasound (PU) examination at the point-of-care can rapidly identify the etiology of acute respiratory failure (ARF) and assess treatment response. The often-subjective classification of PU abnormalities makes it difficult to document change over time and communicate findings across providers. The study goal was to develop a simple, PU scoring system that would allow for standardized documentation, have high interprovider agreement, and correlate with clinical metrics.

METHODS

In this prospective study of 250 adults intubated for ARF, a PU examination was performed at intubation, 48-hours later, and at extubation. A total lung score (TLS) was calculated. Clinical metrics and final diagnosis were extracted from the medical record.

RESULTS

TLS correlated positively with mortality (P = .03), ventilator hours (P = .003), intensive care unit, and hospital length of stay (P = .003, P = .008), and decreasing PaO₂ /FiO₂ (P < .001). Agreement of PU findings was very good (kappa = 0.83). Baseline TLS and subscores differed significantly between ARF categories (nonpulmonary, obstructive, and parenchymal disease).

CONCLUSIONS

A quick, scored, PU examination was associated with clinical metrics, including mortality among a diverse population of patients intubated for ARF. In addition to diagnostic and prognostic information at the bedside, a standardized and quantifiable approach to PU provides objectivity in serial assessment and may enhance communication of findings between providers.

Assessment of Pulmonary Edema: Principles and Practice

Pulmonary edema increasingly is recognized as a perioperative complication affecting outcome. Several risk factors have been identified, including those of cardiogenic origin, such as heart failure or excessive fluid administration, and those related to increased pulmonary capillary permeability secondary to inflammatory mediators. Effective treatment requires prompt diagnosis and early intervention. Consequently, over the past 2 centuries a concentrated effort to develop clinical tools to rapidly diagnose pulmonary edema and track response to treatment has occurred. The ideal properties of such a tool would include high sensitivity and specificity, easy availability, and the ability to diagnose early accumulation of lung water before the development of the full clinical presentation. In addition, clinicians highly value the ability to precisely quantify extravascular lung water accumulation and differentiate hydrostatic from high permeability etiologies of pulmonary edema. In this review, advances in understanding the physiology of extravascular lung water accumulation in health and in disease and the various mechanisms that protect against the development of pulmonary edema under physiologic conditions are discussed. In addition, the various bedside modalities available to diagnose early accumulation of extravascular lung water and pulmonary edema, including chest auscultation, chest roentgenography, lung ultrasonography, and transpulmonary thermodilution, are examined. Furthermore, advantages and limitations of these methods for the operating room and intensive care unit that are critical for proper modality selection in each individual case are explored.

The clinical practice guideline for the management of ARDS in Japan

BACKGROUND

The Japanese Society of Respiratory Care Medicine and the Japanese Society of Intensive Care Medicine provide here a clinical practice guideline for the management of adult patients with ARDS in the ICU.

METHOD

The guideline was developed applying the GRADE system for performing robust systematic reviews with plausible recommendations. The guideline consists of 13 clinical questions mainly regarding ventilator settings and drug therapies (the last question includes 11 medications that are not approved for clinical use in Japan).

RESULTS

The recommendations for adult patients with ARDS include: we suggest against early tracheostomy (GRADE 2C), we suggest using NPPV for early respiratory management (GRADE 2C), we recommend the use of low tidal volumes at 6-8 mL/kg (GRADE 1B), we suggest setting the plateau pressure at 30cmH20 or less (GRADE2B), we suggest using PEEP within the range of plateau pressures less than or equal to 30cmH2O, without compromising hemodynamics (Grade 2B), and using higher PEEP levels in patients with moderate to severe ARDS (Grade 2B), we suggest using protocolized methods for liberation from mechanical ventilation (Grade 2D), we suggest prone positioning especially in patients with moderate to severe respiratory dysfunction (GRADE 2C), we suggest against the use of high frequency oscillation (GRADE 2C), we suggest the use of neuromuscular blocking agents in patients requiring mechanical ventilation under certain circumstances (GRADE 2B), we suggest fluid restriction in the management of ARDS (GRADE 2A), we do not suggest the use of neutrophil elastase inhibitors (GRADE 2D), we suggest the administration of steroids, equivalent to methylprednisolone 1-2mg/kg/ day (GRADE 2A), and we do not recommend other medications for the treatment of adult patients with ARDS (GRADE1B; inhaled/intravenous β2 stimulants, prostaglandin E1, activated protein C, ketoconazole, and lisofylline, GRADE 1C; inhaled nitric oxide, GRADE 1D; surfactant, GRADE 2B; granulocyte macrophage colony-stimulating factor, N-acetylcysteine, GRADE 2C; Statin.).

CONCLUSIONS

This article was translated from the Japanese version originally published as the ARDS clinical practice guidelines 2016 by the committee of ARDS clinical practice guideline (Tokyo, 2016, 293p, available from http://www.jsicm.org/ARDSGL/ARDSGL2016.pdf). The original article, written for Japanese healthcare providers, provides points of view that are different from those in other countries.

Transpulmonary thermodilution: advantages and limits

Background

For complex patients in the intensive care unit or in the operating room, many questions regarding their haemodynamic management cannot be answered with simple clinical examination. In particular, arterial pressure allows only a rough estimation of cardiac output. Transpulmonary thermodilution is a technique that provides a full haemodynamic assessment through cardiac output and other indices.

Main body

Through the analysis of the thermodilution curve recorded at the tip of an arterial catheter after the injection of a cold bolus in the venous circulation, transpulmonary thermodilution intermittently measures cardiac output. This measure allows the calibration of pulse contour analysis. This provides continuous and real time monitoring of cardiac output, which is not possible with the pulmonary artery catheter. Transpulmonary thermodilution provides several variables beyond cardiac output. It estimates the end-diastolic volume of the four cardiac cavities, which is a marker of cardiac preload. It provides an estimation of the systolic function of the combined ventricles. It is more direct than the pulmonary artery catheter, but does not allow the distinct estimation of right and left cardiac function. It is easier and faster to perform than echocardiography, but does not provide a full evaluation of the cardiac structure and function. Transpulmonary thermodilution has the unique advantage of being able to estimate at the bedside extravascular lung water, which quantifies the volume of pulmonary oedema, and pulmonary vascular permeability, which quantifies the degree of a pulmonary capillary leak. Both indices are helpful for guiding fluid strategy, especially in case of acute respiratory distress syndrome.

Conclusions

Transpulmonary thermodilution provides a full cardiovascular evaluation that allows one to answer many questions regarding haemodynamic management. It belongs to the category of “advanced” devices that are indicated for the most critically ill and/or complex patients.

Age-Related Changes in Immunological and Physiological Responses Following Pulmonary Challenge

This review examines the current status of knowledge of sepsis and pneumonia in the elderly population and how the dynamics of the pulmonary challenge affects outcome and consequences. Led by an unprecedented shift in demographics, where a larger proportion of the population will reach an older age, clinical and experimental research shows that aging is associated with certain pulmonary changes, but it is during infectious insult of the lungs, as in the case of pneumonia, that the age-related differences in responsiveness and endurance become obvious and lead to a worse outcome than in the younger population. This review points to the neutrophil, and the endothelium as important players in understanding age-associated changes in responsiveness to infectious challenge of the lung. It also addresses how the immunological set-point influences injury-repair phases, remote organ damage and how intake of drugs may alter the state of responsiveness in the users. Further, it points out the importance of considering age as a factor in inclusion criteria in clinical trials, in vitro/ex vivo experimental designs and overall interpretation of results.

Hemodynamic Analysis of Pediatric Septic Shock and Cardiogenic Shock Using Transpulmonary Thermodilution

Septic shock and cardiogenic shock are the two most common types of shock in children admitted to pediatric intensive care units (PICUs). The aim of the study was to investigate which hemodynamic variables were associated with mortality in children with shock. We retrospectively analyzed 50 children with shock (37 septic shock cases and 13 cardiogenic shock cases) in the PICU and monitored their hemodynamics using transpulmonary thermodilution from 2003 to 2016. Clinical factors were analyzed between the patients with septic and cardiogenic shock. In addition, hemodynamic parameters associated with mortality were analyzed. The 28-day mortality was significantly higher in the septic group than in the cardiogenic group (p = 0.016). Initially, the parameters of cardiac output and cardiac contractility were higher in the septic group (p < 0.05) while the parameters of preload and afterload were all higher in the cardiogenic group (p < 0.05). Cardiac index was significantly lower in the nonsurvivors of cardiogenic shock at the time of initial admission and after the first 24 hours (both p < 0.05), while systemic vascular resistance index (SVRI) was significantly lower in the nonsurvivors of septic shock (p < 0.001). Therefore, during the first 24 hours after intensive care, SVRI and cardiac index are the most important hemodynamic parameters associated with mortality.

How Useful is Extravascular Lung Water Measurement in Managing Lung Injury in Intensive Care Unit?

Context:

The primary goal of septic shock management is optimization of organ perfusion, often at the risk of overloading the interstitium and causing pulmonary edema. The conventionally used end points of resuscitation do not generally include volumetric parameters such as extravascular lung water index (EVLWI) and pulmonary vascular permeability index (PVPI).

Aims:

This study aimed to assess the prognostic value of EVLWI and PVPI by calculating their correlation with the severity of lung injury.

Settings and Design:

This prospective observational study included twenty mechanically ventilated critically ill patients with Acute Physiology and Chronic Health Evaluation score (APACHE II) >20.

Subjects and Methods:

EVLWI and PVPI were measured using transpulmonary thermodilution, and simultaneously, PaO₂:FiO₂ ratio, alveolar-arterial gradient of oxygen (AaDO₂), and chest radiograph scores from two radiologists were obtained.

Statistical Analysis:

The correlation of EVLWI and PVPI with chest radiograph scores, PaO₂:FiO₂ ratio, and AaDO₂ were calculated. The inter-observer agreement between the two radiologists was tested using kappa test.

Results:

EVLWI and PVPI correlated modestly with PaO₂:FiO₂ (r = −0.32, P = 0.0004; r = −0.39, P = 0.0001). There was a better correlation of EVLWI and PVPI with PaO₂:FiO₂ ratio (r = −0.71, P < 0.0001; r = −0.58, P = 0.0001) in the acute respiratory distress syndrome (ARDS) subgroup. The EVLWI values correlated significantly with corresponding chest radiograph scores (r = 0.71, P < 0.0001 for observer 1 and r = 0.68, P < 0.0001 for observer 2).

Conclusions:

EVLWI and PVPI may have a prognostic significance in the assessment of lung injury in septic shock patients with ARDS. Further research is required to reveal the usefulness of EVLWI as an end point of fluid resuscitation in the management of septic shock with ARDS.

Effects of Early Continuous Venovenous Hemofiltration on E-Selectin, Hemodynamic Stability, and Ventilatory Function in Patients with Septic-Shock-Induced Acute Respiratory Distress Syndrome

Objective. To investigate the effects of 72-hour early-initiated continuous venovenous hemofiltration (ECVVH) treatment in patients with septic-shock-induced acute respiratory distress syndrome (ARDS) (not acute kidney injury, AKI) with regard to serum E-selectin and measurements of lung function and hemodynamic stability. Methods. This prospective nonblinded single institutional randomized study involved 51 patients who were randomly assigned to receive or not receive ECVVH, an ECVVH group (n = 24) and a non-ECVVH group (n = 27). Besides standard therapies, patients in ECVVH group underwent CVVH for 72 h. Results. At 0 and 24 h after initiation of treatment, arterial partial pressure of oxygen/fraction of inspired oxygen (PaO₂/FiO₂) ratio, extravascular lung water index (EVLWI), and E-selectin level were not significantly different between groups (all P > 0.05). Compared to non-ECVVH group, PaO₂/FiO₂ is significantly higher and EVLWI and E-selectin level are significantly lower in ECVVH group (all P < 0.05) at 48 h and 72 h after initiation of treatment. The lengths of mechanical ventilation and stay in intensive care unit (ICU) were shorter in ECVVH group (all P < 0.05), but there was no difference in 28-day mortality between two groups. Conclusions. In patients with septic-shock-induced ARDS (not AKI), treatment with ECVVH in addition to standard therapies improves endothelial function, lung function, and hemodynamic stability and reduces the lengths of mechanical ventilation and stay in ICU.

Advanced Hemodynamic Management in Patients with Septic Shock

In patients with sepsis and septic shock, the hemodynamic management in both early and later phases of these "organ dysfunction syndromes" is a key therapeutic component. It needs, however, to be differentiated between "early goal-directed therapy" (EGDT) as proposed for the first 6 hours of emergency department treatment by Rivers et al. in 2001 and "hemodynamic management" using advanced hemodynamic monitoring in the intensive care unit (ICU). Recent large trials demonstrated that nowadays protocolized EGDT does not seem to be superior to "usual care" in terms of a reduction in mortality in emergency department patients with early identified septic shock who promptly receive antibiotic therapy and fluid resuscitation. "Hemodynamic management" comprises (a) making the diagnosis of septic shock as one differential diagnosis of circulatory shock, (b) assessing the hemodynamic status including the identification of therapeutic conflicts, and (c) guiding therapeutic interventions. We propose two algorithms for hemodynamic management using transpulmonary thermodilution-derived variables aiming to optimize the cardiocirculatory and pulmonary status in adult ICU patients with septic shock. The complexity and heterogeneity of patients with septic shock implies that individualized approaches for hemodynamic management are mandatory. Defining individual hemodynamic target values for patients with septic shock in different phases of the disease must be the focus of future studies.

The effects of colloids or crystalloids on acute respiratory distress syndrome in swine (<em>Sus scrofa</em>) models with severe sepsis: analysis on extravascular lung water, IL-8, and VCAM-1

Background: Acute respiratory distress syndrome (ARDS) is a fatal complication of severe sepsis. Due to its higher molecular weight, the use of colloids in fluid resuscitation may be associated with fewer cases of ARDS compared to crystalloids. Extravascular lung water (EVLW) elevation and levels of interleukin-8 (IL-8) and vascular cell adhesion molecule-1 (VCAM-1) have been studied as indicators playing a role in the pathogenesis of ARDS. The aim of the study was to determine the effects of colloid or crystalloid on the incidence of ARDS, elevation of EVLW, and levels of IL-8 and VCAM-1, in swine models with severe sepsis.Methods: This was a randomized trial conducted at the Laboratory of Experimental Surgery, School of Veterinary Medicine, IPB, using 22 healthy swine models with a body weight of 8 to 12 kg. Subjects were randomly allocated to receive either colloid or crystalloid fluid resuscitation. After administration of endotoxin, clinical signs of ARDS, EVLW, IL-8, and VCAM-1 were monitored during sepsis, severe sepsis, and one- and three hours after fluid resuscitation. Analysis of data using the Wilcoxon test , Kolmogorov-Smirnov test, Mann-Whitney test, unpaired t test.Results: Mild ARDS was more prevalent in the colloid group, while moderate ARDS was more frequent in the crystalloid group. EVLW elevation was lower in the colloid compared to the crystalloid group. There was no significant difference in IL-8 and VCAM-1 levels between the two groups.Conclusion: The use of colloids in fluid resuscitation does not decrease the probability of ARDS events compared to crystalloids. Compared to crystalloids, colloids are associated with a lower increase in EVLWI, but not with IL-8 or VCAM-1 levels.

Distributive shock, cardiac arrhythmias and multiple organ failure following surgery of a fourth ventricular epidermoid

A 33-years-old male patient presented with cardiac arrhythmias, acute shock and multiple organ dysfunction after the surgical removal of a massive epidermoid posterior to the brainstem. The patient initially presented with paraesthesia along the right C6 dermatome due to a big tumour at the brain stem. Surgical removal was performed without adverse events and he was transferred to our intensive care unit (ICU) immediately after the operation. Though initially showing a stable postsurgical course he developed cardiac arrhythmias and a state of acute distributive shock with consecutive multi organ failure. Extensive diagnostic measures could not identify a specific cause for this rapid deterioration. However, under carefully monitored symptomatic therapy the patient improved quickly, was extubated 72 h after admission and discharged from the ICU 6 days later. The follow-up did not show any persisting neurological deficits and no evidence of a residual tumour in the MRI-study.

Extravascular lung water in critical care: recent advances and clinical applications

Extravascular lung water (EVLW) is the amount of fluid that is accumulated in the interstitial and alveolar spaces. In lung oedema, EVLW increases either because of increased lung permeability or because of increased hydrostatic pressure in the pulmonary capillaries, or both. Increased EVLW is always potentially life-threatening, mainly because it impairs gas exchange and reduces lung compliance. The only technique that provides an easy measurement of EVLW at the bedside is transpulmonary thermodilution. The validation of EVLW measurements by thermodilution was based on studies showing reasonable correlations with gravimetry or thermo-dye dilution in experimental and clinical studies. EVLW should be indexed to predicted body weight. This indexation reduces the proportion of ARDS patients for whom EVLW is in the normal range. Compared to non-indexed EVLW, indexed EVLW (EVLWI) is better correlated with the lung injury score and the oxygenation and it is a better predictor of mortality of patients with acute lung injury or acute respiratory distress syndrome (ARDS). Transpulmonary thermodilution also provides the pulmonary vascular permeability index (PVPI), which is an indirect reflection of the integrity of the alveolocapillary barrier. As clinical applications, EVLWI and PVPI may be useful to guide fluid management of patients at risk of fluid overload, as during septic shock and ARDS. High EVLWI and PVPI values predict mortality in several categories of critically ill patients, especially during ARDS. Thus, fluid administration should be limited when EVLWI is already high. Whatever the value of EVLWI, PVPI may indicate that fluid administration is particularly at risk of aggravating lung oedema. In the acute phase of haemodynamic resuscitation during septic shock and ARDS, high EVLWI and PVPI values may warn of the risk of fluid overload and prevent excessive volume expansion. At the post-resuscitation phase, they may prompt initiation of fluid removal thereby achieving a negative fluid balance.

Effect of dobutamine on extravascular lung water index, ventilator function, and perfusion parameters in acute respiratory distress syndrome associated with septic shock

BACKGROUND

The role of dobutamine in the relief of pulmonary edema during septic shock-induced acute respiratory distress syndrome (ARDS) remains undetermined, due to a lack of controllable and quantitative clinical studies. Our objective was to assess the potential effects of dobutamine on extravascular lung water index (ELWI) in septic shock-induced ARDS, reflecting its importance in pulmonary edema. At the same time, ventilator function and perfusion parameters were evaluated.

METHODS

We designed a prospective, non-randomized, non-blinded, controlled study to compare the differences in PiCCO parameters after 6 h of constant dobutamine infusion (15 μg/kg/min), in the baseline parameters in 26 septic shock-related ARDS patients with cardiac index ≥ 2.5I/min/m(2) and hyperlactatemia. These patients (12 survivors/14 non-survivors) were monitored using the PiCCO catheter system within 48 h of onset of septic shock. The dynamic changes in ELWI, which is typically used for quantifying the extent of pulmonary edema, were evaluated, and the corresponding ventilator function and tissue perfusion parameters were also measured.

RESULTS

Decreasing ELWI (p = 0.0376) was accompanied by significantly decreased SVRI (p < 0.0001). Despite a significant increase in cardiac output (p < 0.0001), no differences were found in ITBI or GEDI. Moreover, the required dose of norepinephrine was decreased (p = 0.0389), and urine output was increased (p = 0.0358), accompanied by stabilized lactacidemia and MAP. Additionally, airway pressure was moderately improved.

CONCLUSION

During the early stage of septic shock-induced ARDS, dobutamine treatment demonstrated a beneficial effect by relieving pulmonary edema in patients, without a negative elevation in preload or hemodynamics, which might account for the improvements in ventilator function and tissue hypoperfusion.

Restrictive Fluid Resuscitation Leads to Better Oxygenation than Non-Restrictive Fluid Resuscitation in Piglets with Pulmonary or Extrapulmonary Acute Respiratory Distress Syndrome

BACKGROUND

Early goal-directed therapy (EGDT) is used to reduce mortality from septic shock and could be used in early fluid resuscitation of acute respiratory distress syndrome (ARDS). The aim of the present study was to assess the effects of restrictive (RFR) and nonrestrictive fluid resuscitation (NRFR) on hemodynamics, oxygenation, pulmonary function, tissue perfusion, and inflammation in piglets with pulmonary or extrapulmonary ARDS (ARDSp and ARDSexp).

MATERIAL AND METHODS

Chinese miniature piglets (6-8 weeks; 15 ± 1 kg) were randomly divided into 2 groups (n=12/group) for establishing ARDSp and ARDSexp models, and were further divided into 2 subgroups (n=6/subgroup) for performing RFR and NRFR. Piglets were anesthetized and hemodynamic, pulmonary, and oxygenation indicators were collected at different time points for 6 hours. The goal of EGDT was set for PiCCO parameters (mean arterial pressure (MAP), urine output and cardiac index (CI), and central venous oxygen saturation (ScvO2).

RESULTS

Piglets under RFR had lower urine output compared with NRFR, as well as lower total fluid volume (P<0.05). EVLW was decreased in ARDSp+RFR and NRFR, as well as in ARDSexp+RFR, but EVLW increased in ARDSexp+NRFR (P<0.05). PaO2/FiO2 decreased in ARDSp using both methods, but was higher with RFR (P<0.05), and was increased in ARDSexp+RFR. Other pulmonary indicators were comparable. The anti-inflammatory cytokines IL-10 and LXA4 were increased in ARDSexp after RFR (P<0.05), but not in the other groups.

CONCLUSIONS

RFR led to better oxygenation in ARDSp and ARDSexp compared with NRFR, but fluid restriction improved oxygenation in ARDSexp only.

Extravascular lung water and pulmonary vascular permeability index as markers predictive of postoperative acute respiratory distress syndrome: a prospective cohort investigation

OBJECTIVE

Robust markers of subclinical perioperative lung injury are lacking. Extravascular lung water indexed to predicted body weight and pulmonary vascular permeability index are two promising early markers of lung edema. We aimed to evaluate whether extravascular lung water indexed to predicted body weight and pulmonary vascular permeability index would identify patients at risk for clinically significant postoperative pulmonary edema, particularly resulting from the acute respiratory distress syndrome.

DESIGN

Prospective cohort study.

SETTING

Tertiary care academic medical center.

PATIENTS

Adults undergoing high-risk cardiac or aortic vascular surgery (or both) with risk of acute respiratory distress syndrome.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Extravascular lung water indexed to predicted body weight and pulmonary vascular permeability index measurements were obtained intraoperatively and in the early postoperative period. We assessed the accuracy of peak extravascular lung water indexed to predicted body weight and pulmonary vascular permeability index as predictive markers of clinically significant pulmonary edema (defined as acute respiratory distress syndrome or cardiogenic pulmonary edema) using area under the receiver-operating characteristic curves. Associations between extravascular lung water indexed to predicted body weight and pulmonary vascular permeability patient-important with important outcomes were assessed. Of 150 eligible patients, 132 patients (88%) had extravascular lung water indexed to predicted body weight and pulmonary vascular permeability index measurements. Of these, 13 patients (9.8%) had postoperative acute respiratory distress syndrome and 15 patients (11.4%) had cardiogenic pulmonary edema. Extravascular lung water indexed to predicted body weight effectively predicted development of clinically significant pulmonary edema (area under the receiver-operating characteristic curve, 0.79; 95% CI, 0.70-0.89). Pulmonary vascular permeability index discriminated acute respiratory distress syndrome from cardiogenic pulmonary edema alone or no edema (area under the receiver-operating characteristic curve, 0.77; 95% CI, 0.62-0.93). Extravascular lung water indexed to predicted body weight was associated with the worst postoperative PaO2/FIO2, duration of mechanical ventilation, ICU stay, and hospital stay. Peak values for extravascular lung water indexed to predicted body weight and pulmonary vascular permeability index were obtained within 2 hours of the primary intraoperative insult for the majority of patients (> 80%).

CONCLUSIONS

Perioperative extravascular lung water indexed to predicted body weight is an early marker that predicts risk of clinically significant postoperative pulmonary edema in at-risk surgical patients. Pulmonary vascular permeability index effectively discriminated postoperative acute respiratory distress syndrome from cardiogenic pulmonary edema. These measures will aid in the early detection of subclinical lung injury in at-risk surgical populations.

Furosemide infusion in children with dengue fever and hypoxemia

Objectives

To study the role of furosemide infusion in the management of Acute respiratory distress syndrome (ARDS) associated with dengue fever.

Methods

Children between the ages of 1 month to 18 years, who fulfilled the WHO clinical criteria for dengue infection and American European Consensus Criteria criteria for ARDS with Dengue IgM positivity, were evaluated. Patients were studied as group D (receiving diuretic therapy alone) and group B (both ventilation and diuretics), and compared to a historical control group V (ventilation alone). Furosemide infusion was administered at 0.05–0.1 mg/kg/hour for 48 hours, maintaining a urine output of 2–4 mL/kg/hour.

Results

There was a significant difference in survival in the three groups. Significant difference was noted between pre- and postintervention arterial blood gases with respect to PCO₂ (P=0.02), pO₂ (P=0.003), PaO₂/FaO₂ ratio (P<0.001) and alveolar-arteriolar oxygen gradient (P=0.002).

Conclusion

Diuretic infusion improves outcome in dengue with ARDS.

Effect of a selective neutrophil elastase inhibitor on mortality and ventilator-free days in patients with increased extravascular lung water: a post hoc analysis of the PiCCO Pulmonary Edema Study

BACKGROUND

Neutrophil elastase plays an important role in the development and progression of acute respiratory distress syndrome (ARDS). Although the selective elastase inhibitor, sivelestat, is widely used in Japan for treating ARDS patients, its effectiveness remains controversial. The aim of the current study was to investigate the effects of sivelestat in ARDS patients with evidence of increased extravascular lung water by re-analyzing a large multicenter study database.

METHODS

A post hoc analysis of the PiCCO Pulmonary Edema Study was conducted. This multicenter prospective cohort study included 23 institutions in Japan. Adult mechanically ventilated ARDS patients with an extravascular lung water index of >10 mL/kg were included and propensity score analyses were performed. The endpoints were 28-day mortality and ventilator-free days (VFDs).

RESULTS

Patients were categorized into sivelestat (n = 87) and control (n = 77) groups, from which 329 inverse probability-weighted group patients (162 vs. 167) were generated. The overall 28-day mortality was 31.1% (51/164). There was no significant difference in 28-day mortality between the study groups (sivelestat vs. control; unmatched: 29.9% vs. 32.5%; difference, -2.6%, 95% confidence interval (CI), -16.8 to 14.2; inverse probability-weighted: 24.7% vs. 29.5%, difference, -4.8%, 95% CI, -14.4 to 9.6). Although administration of sivelestat did not alter the number of ventilator-free days (VFDs) in the unmatched (9.6 vs. 9.7 days; difference, 0.1, 95% CI, -3.0 to 3.1), the inverse probability-weighted analysis identified significantly more VFDs in the sivelestat group than in the control group (10.7 vs. 8.4 days, difference, -2.3, 95% CI, -4.4 to -0.2).

CONCLUSIONS

Although sivelestat did not significantly affect 28-day mortality, this treatment may have the potential to increase VFDs in ARDS patients with increased extravascular lung water. Prospective randomized controlled studies are required to confirm the results of the current study.

Comparison of the accuracy of transpulmonary thermodilution measurement using indicators of different temperatures

Transpulmonary thermodilution measurement is a convenient method for hemodynamic monitoring. However, the previously reported indicator temperature was not consistent. This study aimed to compare the accuracy of Pulse index Continuous Cardiac Output (PiCCO) monitoring using indicators of different temperatures. A total of 104 critically ill patients received PiCCO monitoring using indicators of either 0°C or 8°C. The PiCCO measurements, including general ejection fraction, global end-diastolic index, and cardiac index, were compared between the two temperatures, and were also correlated with that of transesophageal echocardiography (TEE). The two indicator temperatures differed significantly in hemodynamic measurements (P<0.01). PiCCO measurements with either indicator temperatures showed positive correlation with TEE results (P<0.05). The 0°C indicator had universally higher correlation coefficients than the 8°C indicator. So, PiCCO monitoring with the 0°C indicator might have better accuracy than the 8°C indicator.

Albumin versus other fluids for fluid resuscitation in patients with sepsis: a meta-analysis

BACKGROUND

Early fluid resuscitation is vital to patients with sepsis. However, the choice of fluid has been a hot topic of discussion. The objective of this study was to evaluate whether the use of albumin-containing fluids for resuscitation in patients with sepsis was associated with a decreased mortality rate.

METHODS

We systematically searched PubMed, EMBASE and Cochrane library for eligible randomized controlled trials (RCTs) up to March 2014. The selection of eligible studies, assessment of methodological quality, and extraction of all relevant data were conducted by two authors independently.

RESULTS

In total, 15 RCTs were eligible for analysis. After pooling the data, we found there was no significant effect of albumin-containing fluids on mortality in patients with sepsis of any severity (RR: 0.94, 95% CI: 0.87, 1.02 and RD: -0.01, 95% CI: -0.03, 0.01). The results were robust to subgroup analyses, sensitivity analyses and trial sequential analyses.

CONCLUSION

The present meta-analysis did not demonstrate significant advantage of using albumin-containing fluids for resuscitation in patients with sepsis of any severity. Given the cost-effectiveness of using albumin, crystalloids should be the first choice for fluid resuscitation in septic patients.

Improving diagnostic accuracy in assessing pulmonary edema on bedside chest radiographs using a standardized scoring approach

Background

To assess the value of a score-based system which allows standardized evaluation of pulmonary edema on bedside chest radiographs (CXRs) under routine clinical conditions.

Methods

Seven experienced readers assessed bedside CXRs of ten patients with an extravascular lung water (EVLW)-value of ≤ 8 mL/kg (range: 4–8 mL/kg; indicates no pulmonary edema) and a series of ten patients with an EVLW-value of ≥ 15 mL/kg (range: 15–21 mL/kg; = indicates a pulmonary edema) with and without customized software which would permit a standardized assessment of the various indications of pulmonary edema. The software provides a score that identifies patients with and without pulmonary edema. EVLW-values were measured instantly after bedside CXR imaging using a pulse contour cardiac output (PiCCO) system and served as a reference standard. The patients were non-traumatic and not treated with diuretics or dobutamine during bedside CXR imaging and the PiCCO measurements. Mean sensitivity, specificity, positive and negative predictive value, the percentage of overall agreement and the free-marginal multirater kappa value was calculated for both the standard and the standardized score-based approach. The net reclassification index was calculated for each reader as well as for all readers.

Results

Evaluation of bedside CXRs by means of the score-based approach took longer (23 ± 12 seconds versus 7 ± 3 seconds without the use of the software) but improved radiologists’ sensitivity (from 57 to 77%), specificity (from 90 to 100%) and the free-marginal multirater kappa value (from 0.34 to 0.68). The positive predictive value was raised from 85 to 100% and the negative predictive value from 68 to 81%. A net reclassification index of 0.3 (all readers) demonstrates an improvement in prediction performance gained by the score-based approach. The percentage of overall agreement was 67% with the standard approach and 84% with the software-based approach.

Conclusions

The diagnostic accuracy of bedside CXRs to discriminate patients with elevated EVLW-values from those with a normal value can be improved with the use of a standardized score-based approach. The investigated system is freely available as a web-based application (accessible via: http://www.radiologie.uk-erlangen.de/aerzte-und-zuweiser/edema).

Propofol increases preload dependency in septic shock patients

BACKGROUND

Predicting fluid responsiveness is crucial for fluid administration in septic shock patients. Midazolam and propofol decrease vascular tone and venous return, which may influence preload dependency. However, little is known about the effects of these two sedatives on preload dependency in septic shock patients. We evaluated the effects of sedation with propofol or midazolam on preload dependency in septic shock patients who have been fluid resuscitated.

METHODS

Forty-three septic shock patients who were undergoing early goal-directed therapy resuscitated within 24 h were enrolled. The patients were randomly divided into the midazolam group and the propofol group. An initial passive leg-raising test (PLR1) was performed to evaluate passive leg raising test (PLR) responsiveness. Then, the patients were infused with midazolam or propofol. After increasing the doses of the sedatives to titrate to a Ramsay 4 score, a second passive leg raising test (PLR2) was conducted to evaluate PLR responsiveness. The primary end-point was the preload dependency before and after sedation with midazolam or propofol.

RESULTS

In the midazolam-PLR1-negative patients, there was no difference between the changes in the cardiac index induced by PLR1 (PLR1-Δ cardiac function index [CI]) and the changes in the cardiac index induced by PLR2 (PLR2-Δ CI) (+1.4% ± 7.4% versus +1.7% ± 6.4%, P > 0.05). However, in the propofol-PLR1-negative patients, there was a significant increase in the PLR-Δ CI after sedation to a Ramsay 4 score compared with a Ramsay 3 score (+7.3% ± 4.8% versus +3.2% ± 4.7%, P = 0.008). There were no differences between PLR1-Δ CI and PLR2-Δ CI within the midazolam-PLR1-positive patients or within the propofol-PLR1-positive patients.

CONCLUSIONS

In titrating the sedation level from a Ramsay 3 score to a Ramsay 4 score, propofol but not midazolam increased preload dependency in septic shock patients with fluid nonresponsiveness.

Early-phase changes of extravascular lung water index as a prognostic indicator in acute respiratory distress syndrome patients

Background

The features of early-phase acute respiratory distress syndrome (ARDS) are leakage of fluid into the extravascular space and impairment of its reabsorption, resulting in extravascular lung water (EVLW) accumulation. The current study aimed to identify how the initial EVLW values and their change were associated with mortality.

Methods

This was a post hoc analysis of the PiCCO Pulmonary Edema Study, a multicenter prospective cohort study that included 23 institutions. Single-indicator transpulmonary thermodilution-derived EVLW index (EVLWi) and conventional prognostic factors were prospectively collected over 48 h after enrollment. Associations between 28-day mortality and each variable including initial (on day 0), mean, maximum, and Δ (subtracting day 2 from day 0) EVLWi were evaluated.

Results

We evaluated 192 ARDS patients (median age, 69 years (quartile, 24 years); Sequential Organ Failure Assessment (SOFA) score on admission, 10 (5); all-cause 28-day mortality, 31%). Although no significant differences were found in initial, mean, or maximum EVLWi, Δ-EVLWi was significantly higher (i.e., more reduction in EVLWi) in survivors than in non-survivors (3.0 vs. −0.3 mL/kg, p = 0.006). Age, maximum, and Δ-SOFA scores and Δ-EVLW were the independent predictors for survival according to the Cox proportional hazard model. Patients with Δ-EVLWi > 2.8 had a significantly higher incidence of survival than those with Δ-EVLWi ≤ 2.8 (log-rank test, χ² = 7.08, p = 0.008).

Conclusions

Decrease in EVLWi during the first 48 h of ARDS may be associated with 28-day survival. Serial EVLWi measurements may be useful for understanding the pathophysiologic conditions in ARDS patients. A large multination confirmative trial is required.

Association between different indexations of extravascular lung water (EVLW) and PaO2/FiO2: a two-center study in 231 patients

Background

Variability of body weight (BW) and height calls for indexation of volumetric hemodynamic parameters. Extravascular lung water (EVLW) has formerly been indexed to actual BW (BW_act) termed EVLW-index (EVLWI). In overweight patients indexation to BW_act might inappropriately lower indexed EVLWI_act. Several studies suggest indexation of EVLWI to predicted BW (EVLWI_pred). However, data regarding association of EVLWI_act and EVLW_pred to mortality and PaO₂/FiO₂ are inconsistent. Two recent studies based on biometric database-analyses suggest indexation of EVLWI to height (EVLWI_height). Therefore, our study compared the association of un-indexed EVLW, EVLWI_height, EVLW_pred and EVLWI_act to PaO₂/FiO₂ and Oxygenation index (OI = mean airway pressure*FiO₂*/PaO₂).

Methods

A total of 2119 triplicate transpulmonary thermodilutions (TPTDs; PiCCO; Pulsion Medical-Systems, Germany) were performed in 50 patients from the evaluation, and 181 patients from the validation groups. Correlations of EVLW and EVLWI to PaO₂/FiO₂, OI and ROC-AUC-analyses regarding PaO₂/FiO₂<200 mmHg (primary endpoint) and OI>10 were performed.

Results

In the evaluation group, un-indexed EVLW (AUC 0.758; 95%-CI: 0.637-0.880) and EVLWI_height (AUC 0.746; 95%-CI: 0.622-0.869) provided the largest ROC-AUCs regarding PaO₂/FiO₂<200 mmHg. The AUC for EVLWI_pred was smaller (0.713). EVLWI_act provided the smallest AUC (0.685). This was confirmed in the validation group: EVLWI_height provided the largest AUC (0.735), EVLWI_act (0.710) the smallest. In the merged data-pool, AUC was significantly greater for EVLWI_height (0.729; 95%-CI: 0.674–0.784) compared to all other indexations including EVLWI_act (ROC-AUC 0.683, p = 0.007) and EVLWI_pred (ROC-AUC 0.707, p = 0.015). The association of EVLW(I) was even stronger to OI compared to PaO₂/FiO₂. In the merged data-pool, EVLWI_height provided the largest AUC regarding “OI>10” (0.778; 95%-CI: 0.713–0.842) compared to 0.739 (95%-CI: 0.669–0.810) for EVLWI_act and 0.756 (95%-CI: 0.688–0.824) for EVLWI_pred.

Conclusions

Indexation of EVLW to height (EVLWI_height) improves the association of EVLW(I) to PaO₂/FiO₂ and OI compared to all other indexations including EVLWI_pred and EVLWI_act. Also considering two recent biometric database analyses, EVLWI should be indexed to height.

Lung injury and its prognostic significance in acute liver failure

OBJECTIVE

Hypoxemia is a feared complication of acute liver failure, and high oxygen requirements will frequently lead to removal of patients from the transplant list. As data regarding the prevalence and outcome of acute respiratory distress syndrome in acute liver failure are scant and hypoxemia being a commonly encountered systemic complication, we analyzed radiological, gas exchange, and ventilator data in consecutive patients admitted with acute liver failure.

PATIENTS

Acute liver failure patients receiving mechanical ventilation admitted between January 2007 and February 2011 were included.

INTERVENTIONS

Patients were categorized according to the Berlin definition as: no acute respiratory distress syndrome, acute respiratory distress syndrome (PaO2/FIO2 < 300 mm Hg), and subdivisions of mild, moderate, and severe acute respiratory distress syndrome (200-300 mm Hg, 100-200 mm Hg, and < 100 mm Hg, respectively). Chest radiographs were independently assessed by two observers for the presence or absence of acute respiratory distress syndrome. Absence of left atrial pressure elevation was based on combined hemodynamic and echocardiographic assessment.

MEASUREMENTS AND MAIN RESULTS

Two hundred acute liver failure patients were admitted during the study period of whom 148, median age 39 years (16-74 yr), were included. Thirty-one (21%) had acute respiratory distress syndrome (17 mild acute respiratory distress syndrome [12%], 9 moderate acute respiratory distress syndrome [12%], and 5 severe acute respiratory distress syndrome) within the first 72 hours following admission. Acute respiratory distress syndrome patients required higher positive end-expiratory pressure (7 vs 6 vs 10 vs 15 cm H2O for no, mild, moderate, or severe acute respiratory distress syndrome, p = 0.014), had reduced respiratory system compliance (34 vs 29 vs 30 vs 23 L/cm H2O, p = 0.028), and an increased number of ventilator days (no acute respiratory distress syndrome, 10 d; mild acute respiratory distress syndrome acute lung injury, 12 d; moderate acute respiratory distress syndrome, 23 d; severe acute respiratory distress syndrome, 22 d; p = 0.097). Duration of liver intensive therapy unit stay (p = 0.175), survival (p = 0.877), inotrope requirements (p = 0.495), need for extracorporeal renal support (p = 0.565), and severity of organ failure scores were not affected. Extravascular lung water index had a moderate sensitivity of 65% and specificity of 77% for the prediction of acute respiratory distress syndrome.

CONCLUSION

The prevalence of lung injury is relatively low in acute liver failure, where 21% fulfilled acute respiratory distress syndrome criteria. Overall presence of acute respiratory distress syndrome appeared to have a limited impact on outcome.

Extravascular lung water and pulmonary arterial wedge pressure for fluid management in patients with acute respiratory distress syndrome

Background

Extravascular lung water (EVLW) is a sensitive prognostic indicator of pulmonary edema. Thus, EVLW may be an advantageous method of fluid management. This study aims to evaluate the outcomes of using EVLW and pulmonary artery wedge pressure (PAWP) as strategies for fluid management in patients with acute respiratory distress syndrome (ARDS).

Methods

Twenty-nine patients were randomly divided into the EVLW and PAWP groups. The survival rate, ICU (Intensive Care Unit) length of stay, duration of mechanical ventilation, acute lung injury scores, and oxygenation index of the EVLW and PAWP groups were compared.

Results

No significant difference in the survival rates at 28 and 60 days (d) after treatment was found between the two groups (p = 0.542). The duration of mechanical ventilation and ICU length of stay were significantly lower (p < 0.05) in the EVLW group than in the PAWP group. The 7 d cumulative fluid balance was -783 ± 391 ml in the EVLW group and -256 ± 514 ml in the PAWP group (p < 0.05). Compared with the PAWP group, the EVLW group showed improved oxygenation index (p = 0.006).

Conclusions

EVLW for fluid management improved clinical results in patients with ARDS better than PAWP.

The role for invasive monitoring in acute lung injury

Because acute lung injury (ALI) may arise from diverse and heterogeneous clinical insults, monitoring strategies for patients with ALI are heterogeneous as well. This review divides the monitoring strategies for ALI into three distinct phases. The "at-risk phase" is the period in which patients are at risk for ALI, and interventions may be applied to minimize or eliminate this risk. The "ALI phase" is the period during which ALI has occurred and requires attentive clinical management. The "resolution phase" is the period defined by resolution of ALI and successful discontinuation of mechanical ventilation. These phases are arbitrary, but they provide a useful framework for discussing the temporal changes in patient condition and monitoring goals in ALI.Invasive hemodynamic monitoring has specific roles in each phase of therapy for patients with ALI: pre-ALI, peri-ALI, and post-ALI. The primary goals are to optimize fluid resuscitation to prevent organ dysfunction, including ALI, and if ALI occurs to additional optimize fluid balance vis-à-vis the lung. By judicious application of invasive hemodynamic monitoring, particularly in its more modern iterations, clinicians can optimize the ebb and flow phases common to critically ill patients. This is vitally important given our current and growing understanding of the relationship between fluid balance and important clinical outcomes, multiple organ dysfunction syndrome, and mortality.