Year in review in Intensive Care Medicine 2011: III. ARDS and ECMO, weaning, mechanical ventilation, noninvasive ventilation, pediatrics and miscellanea

Comparison of High Flow Nasal Cannula and Continuous Positive Airway Pressure in COVID-19 Patients With Acute Respiratory Distress Syndrome in Critical Care Unit: A Randomized Control Study

Background and objective Acute hypoxic respiratory failure in coronavirus disease 2019 (COVID-19) pneumonia has been treated with oxygen delivered by oxygen masks and non-invasive ventilation (NIV) with continuous positive airway pressure (CPAP), and more recently with high-flow nasal cannula (HFNC) devices. There is a paucity of randomized controlled trials to compare the efficacy of CPAP with HFNC in COVID-19 pneumonia. We conceptualized a randomized control study to compare the efficacy of HFNC and CPAP in reducing the need for invasive mechanical ventilation, estimation of mechanical ventilation-free days, and risk of intubation in COVID-19 patients with hypoxic respiratory failure. Methodology One hundred consecutive patients who satisfied the inclusion criteria were included in the trial. The patients were then randomly allocated to receive either CPAP or HFNC with settings as per the study protocol. The patients were deemed to have achieved the study endpoint when they were intubated due to any reason or successfully weaned from NIV to conventional oxygen therapies. The number of patients who required invasive ventilation and the number of invasive ventilation-free days were recorded and analyzed. Results Nineteen (38%) patients in the CPAP group and 30 (60%) patients in the HFNC group required invasive mechanical ventilation and the difference was statistically significant (p = 0.03, 95%CI: 0.1829-0.9129). The median number of days free of invasive mechanical ventilation in the CPAP group (median=5 (interquartile range (IQR(=5,6)) was more than in the HFNC group (median=4 (IQR=3,4)) and this difference was statistically significant (p<0.000). The secondary analysis of risk evaluation for intubation done using the Cox regression model showed no significant factors that could have contributed to intubation in the study population. The Kaplan-Meyer curve was used to express the probability of a patient getting intubated and the calculated hazard ratio was 2.29. Conclusion The administration of CPAP significantly reduced the intubation rate and prolonged invasive mechanical ventilation-free period in COVID-19 patients with hypoxic respiratory failure. We also inferred a two-fold increase in the risk of intubation in patients receiving HFNC compared to CPAP.

Extracorporeal Life Support: Four Decades and Counting

Extracorporeal membrane oxygenation (ECMO) or extracorporeal life support (ECLS) is a form of heart lung bypass that is used to support neonates, pediatrics, and adult patients with cardiorespiratory failure for days or weeks till organ recovery or transplantation. Venoarterial (VA) and venovenous (VV) ECLS are the most common modes of support. ECLS circuit components and monitoring have been evolving over the last 40 years. The technology is safer, simpler, and more durable with fewer complications. The use of neonatal respiratory ECLS use has been declining over the last two decades, while adult respiratory ECLS is growing especially since the H1N1 influenza pandemic in 2009. This review provides an overview of ECLS evolution over the last four decades, its use in neonatal, pediatric and adults, description of basic principles, circuit components, complications, and outcomes as well as a quick look into the future.

Pediatric Noninvasive Ventilation

Noninvasive ventilation has been available for many years for use in the pediatric population. Historically, continuous positive airway pressure and bilevel positive airway pressure modes were used for respiratory diseases, including neonatal apnea, bronchiolitis, asthma, and pneumonia. Newer studies suggest that noninvasive ventilation is also an effective and safe mode for support of children with acute respiratory distress syndrome and respiratory failure. The newest type of noninvasive respiratory support is high flow nasal cannula, which has gained popularity in the past few years and its use is being justified in the literature. Studies have shown that these therapies can decrease the need for intubation and ventilation, decrease length of intensive care days, and increase patient comfort. Additional research is needed to support optimal setting selection and recommendations for the use of noninvasive therapies for infants and children.

Long-term neuropsychological outcomes in children and adolescents after cardiac arrest

PURPOSE

Research into neuropsychological functioning of survivors of cardiac arrest (CA) in childhood is scarce. We sought to assess long-term neuropsychological functioning in children and adolescents surviving CA.

METHODS

Neuropsychological follow-up study involving all consecutive children surviving CA between January 2002 and December 2011. Intelligence (IQ), language, attention, memory, visual-spatial, and executive functioning were assessed with internationally validated, neuropsychological tests and questionnaires. Scores were compared with Dutch normative data.

RESULTS

Of 107 eligible children, 47 who visited the outpatient clinic (median follow-up interval: 5.6 years) were analyzed. Fifty-five percent had an in-hospital CA, 86% a non-shockable rhythm, and 49% a respiratory-related etiology. CA survivors scored significantly worse on full-scale IQ (mean = 87.3), verbal IQ (mean = 92.7), performance IQ (mean = 85.6), verbal comprehension index (mean = 93.4), perceptual organization index (mean = 83.8), and processing speed index (mean = 91.1), than the norm population (mean IQ = 100). On neuropsychological tests, compared with norms, respectively adjusted for IQ, significantly worse scores were found on visual memory, significantly better on verbal memory (recognition), and comparable outcomes on visual-motor integration, attention, other measures of verbal memory, and executive functioning. On questionnaires, parents reported better executive functioning than the norm, but teachers reported more problems in planning/organizing skills.

CONCLUSIONS

Long-term neuropsychological assessment of CA survivors showed significant weaknesses, but also relatively intact functioning. As deficits in IQ, memory and executive functioning have significant impact on the child, long-term follow-up and neuropsychological support of CA survivors is warranted.

Effects of a recruitment maneuver on plasma levels of soluble RAGE in patients with diffuse acute respiratory distress syndrome: a prospective randomized crossover study

PURPOSE

The soluble form of the receptor for advanced glycation end-products (sRAGE) is a promising marker for epithelial dysfunction, but it has not been fully characterized as a biomarker of acute respiratory distress syndrome (ARDS). Whether sRAGE could inform on the response to ventilator settings has been poorly investigated, and whether a recruitment maneuver (RM) may influence plasma sRAGE remains unknown.

METHODS

Twenty-four patients with moderate/severe, nonfocal ARDS were enrolled in this prospective monocentric crossover study and randomized into a "RM-SHAM" group when a 6-h-long RM sequence preceded a 6-h-long sham evaluation period, or a "SHAM-RM" group (inverted sequences). Protective ventilation was applied, and RM consisted of the application of 40 cmH2O airway pressure for 40 s. Arterial blood was sampled for gas analyses and sRAGE measurements, 5 min pre-RM (or 40-s-long sham period), 5, 30 min, 1, 4, and 6 h after the RM (or 40-s-long sham period).

RESULTS

Mean PaO2/FiO2, tidal volume, PEEP, and plateau pressure were 125 mmHg, 6.8 ml/kg (ideal body weight), and 13 and 26 cmH2O, respectively. Median baseline plasma sRAGE levels were 3,232 pg/ml. RM induced a significant decrease in sRAGE (-1,598 ± 859 pg/ml) in 1 h (p = 0.043). At 4 and 6 h post-RM, sRAGE levels increased back toward baseline values. Pre-RM sRAGE was associated with RM-induced oxygenation improvement (AUC 0.84).

CONCLUSIONS

We report the first kinetics study of plasma sRAGE after RM in ARDS. Our findings reinforce the value of plasma sRAGE as a biomarker of ARDS.

Effectiveness of treatment based on PiCCO parameters in critically ill patients with septic shock and/or acute respiratory distress syndrome: a randomized controlled trial

PURPOSE

To compare treatment based on either PiCCO-derived physiological values or central venous pressure (CVP) monitoring, we performed a prospective randomized controlled trial with group sequential analysis.

METHODS

Consecutive critically ill patients with septic shock and/or ARDS were included. The planned total sample size was 715. The primary outcome was 28-day mortality after randomization. Participants underwent stratified randomization according to the classification of ARDS and/or septic shock. Caregivers were not blinded to the intervention, but participants and outcome assessors were blinded to group assignment.

RESULTS

The study was stopped early because of futility after enrollment of 350 patients including 168 in the PiCCO group and 182 in the control group. There was no loss to follow-up and data from all enrolled participants were analyzed. The result showed that treatment based on PiCCO-derived physiological values was not able to reduce the 28-day mortality risk (odds ratio 1.00, 95 % CI 0.66-1.52; p = 0.993). There was no difference between the two groups in secondary outcomes such as 14-day mortality (40.5 vs. 41.2 %; p = 0.889), ICU length of stay (median 9 vs. 7.5 days; p = 0.598), days free of vasopressors (median 14.5 vs. 19 days; p = 0.676), and days free of mechanical ventilation (median 3 vs. 6 days; p = 0.168). No severe adverse event was reported in both groups.

CONCLUSION

On the basis of our study, PICCO-based fluid management does not improve outcome when compared to CVP-based fluid management.

Emodin ameliorates LPS-induced acute lung injury, involving the inactivation of NF-κB in mice

Acute lung injury (ALI) and its severe manifestation of acute respiratory distress syndrome (ARDS) are well-known illnesses. Uncontrolled and self-amplified pulmonary inflammation lies at the center of the pathology of this disease. Emodin, the bio-active coxund of herb Radix rhizoma Rhei, shows potent anti-inflammatory properties through inactivation of nuclear factor-κB (NF-κB). The aim of this study was to evaluate the effect of emodin on lipopolysaccharide (LPS)-induced ALI in mice, and its potential bio-mechanism. In our study, BALB/c mice were stimulated with LPS to induce ALI. After 72 h of LPS stimulation, pulmonary pathological changes, lung injury scores, pulmonary edema, myeloperoxidase (MPO) activity, total cells, neutrophils, macrophages, TNF-α, IL-6 and IL-1β in bronchoalveolar lavage fluid (BALF), and MCP-1 and E-selectin expression were notably attenuated by emodin in mice. Meanwhile, our data also revealed that emodin significantly inhibited the LPS-enhanced the phosphorylation of NF-κB p65 and NF-κB p65 DNA binding activity in lung. Our data indicates that emodin potently inhibits LPS-induced pulmonary inflammation, pulmonary edema and MCP-1 and E-selectin expression, and that these effects were very likely mediated by inactivation of NF-κB in mice. These results suggest a therapeutic potential of emodin as an anti-inflammatory agent for ALI/ARDS treatment.

Effect of the use of low and high potency statins and sepsis outcomes

INTRODUCTION

Although statins have been shown to have cholesterol-lowering effects, their pleiotropic benefits on sepsis remain a matter of debate. In addition, the influence of statin potency on sepsis-related mortality has never been explored. The aim of our study was to determine the sepsis outcomes of low- and high-potency statin users and non-users.

METHODS

This nationwide, population-based, propensity score-matched analysis used data from the linked administrative databases of Taiwan's National Health Insurance program. Patients were hospitalized for sepsis between 2000 and 2010. All-cause mortality and major adverse consequences of sepsis, such as in-hospital death, intensive care unit admission, shock events, and the use of mechanical ventilation, were assessed. Patients were divided into high-potency statin users (at least 10 mg rosuvastatin, at least 20 mg atorvastatin, or at least 40 mg simvastatin), low-potency statin users (all other statin treatments), and non-users.

RESULTS

A propensity score-matched cohort of 27,792 statin users and 27,792 non-users was included. Of 27,792 statin users, 9,785 (35.2 %) were treated with high-potency statins and 18,007 (64.8 %) were treated with low-potency statins. The 1-year mortality risk was significantly lower among both low-potency [adjusted hazard ratio (aHR) 0.89, 95 % confidence interval (CI) 0.85-0.93] and high-potency (aHR 0.80, 95 % CI 0.75-0.86) statin users compared with non-users. The risks of mortality and adverse consequences of sepsis were lower among high-potency than among low-potency statin users.

CONCLUSIONS

High-potency statin use is associated with a lower risk of sepsis-related mortality compared with low-potency statin use.

Trends in admission prevalence, illness severity and survival of haematological patients treated in Dutch intensive care units

PURPOSE

To explore trends over time in admission prevalence and (risk-adjusted) mortality of critically ill haematological patients and compare these trends to those of several subgroups of patients admitted to the medical intensive care unit (medical ICU patients).

METHODS

A total of 1,741 haematological and 60,954 non-haematological patients admitted to the medical ICU were analysed. Trends over time and differences between two subgroups of haematological medical ICU patients and four subgroups of non-haematological medical ICU patients were assessed, as well as the influence of leukocytopenia.

RESULTS

The proportion of haematological patients among all medical ICU patients increased over time [odds ratio (OR) 1.06; 95 % confidence interval (CI) 1.03-1.10 per year; p < 0.001]. Risk-adjusted mortality was significantly higher for haematological patients admitted to the ICU with white blood cell (WBC) counts of <1.0 × 10(9)/L (47 %; 95 % CI 41-54 %) and ≥1.0 × 10(9)/L (45 %; 95 % CI 42-49 %), respectively, than for patients admitted with chronic heart failure (27 %; 95 % CI 26-28 %) and with chronic liver cirrhosis (38 %; 95 % CI 35-42 %), but was not significantly different from patients admitted with solid tumours (40 %; 95 % CI 36-45 %). Over the years, the risk-adjusted hospital mortality rate significantly decreased in both the haematological and non-haematological group with an OR of 0.93 (95 % CI 0.92-0.95) per year. After correction for case-mix using the APACHE-II score (with WBC omitted), a WBC <1.0 × 10(9)/L was not a predictor of mortality in haematological patients (OR 0.86; 95 % CI 0.46-1.64; p = 0.65). We found no case-volume effect on mortality for haematological ICU patients.

CONCLUSIONS

An increasing number of haematological patients are being admitted to Dutch ICUs. While mortality is significantly higher in this group of medical ICU patients than in subgroups of non-haematological ones, the former show a similar decrease in raw and risk-adjusted mortality rate over time, while leukocytopenia is not a predictor of mortality. These results suggest that haematological ICU patients have benefitted from improved intensive care support during the last decade.

Neurodevelopmental, educational and behavioral outcome at 8 years after neonatal ECMO: a nationwide multicenter study

PURPOSE

Reporting neurodevelopmental outcome of 8-year-old children treated with neonatal extracorporeal membrane oxygenation (ECMO).

METHODS

In a follow-up study in 135 8-year-old children who received neonatal ECMO between 1996 and 2001 we assessed intelligence (Revised Amsterdam Intelligence Test), concentration (Bourdon-Vos test), eye-hand coordination (Developmental Test of Visual-Motor Integration) and behavior (Child Behavior Checklist and Teacher Report Form).

RESULTS

Intelligence fell within normal range (mean IQ 99.9, SD 17.7, n = 125) with 91 % of the children following regular education. Significantly more children attended special education (9 %) or received extra support in regular education (39 %) compared with normative data. Slower working speed (χ(2) = 132.36, p < 0.001) and less accuracy (χ(2) = 12.90, p < 0.001) were found on the Bourdon-Vos test (n = 123) compared with normative data. Eye-hand coordination fell within the normal range (mean 97.6, SD 14.3, n = 126); children with congenital diaphragmatic hernia scored lowest but still normally (mean 91.0, SD 16.4, n = 28). Mothers (n = 117) indicated more somatic and attention behavior problems; teachers (n = 115) indicated more somatic, social, thought, aggression and total problems compared with normative data. Mothers indicated more somatic problems than teachers (p = 0.003); teachers reported more attention problems than mothers (p = 0.036; n = 111).

CONCLUSIONS

Eight-year-old children treated with neonatal ECMO fall in the normal range of intelligence with problems with concentration and behavior. Long-term follow-up for children treated with neonatal ECMO should focus on early detection of (subtle) learning deficits.

One Hundred Ten Days of Extracorporeal Membrane Oxygenation in a Young Woman with Postpartum Cerebral Venous Thrombosis and Acute Respiratory Distress Syndrome

Extracorporeal membrane oxygenation (ECMO) is often the last resort for serious acute respiratory distress syndrome (ARDS) when all non-invasive treatment options have failed to improve the patient's pulmonary condition. We present a successful long-term therapy with ECMO over 110 days in a 28-year-old woman. She developed postpartum cerebral venous thrombosis with severe respiratory insufficiency. Veno-venous ECMO rescued this young patient, allowing for full recovery.