Daniele Guerino Biasucci

Neurally adjusted ventilatory assist vs pressure support ventilation in infants recovering from severe acute respiratory distress syndrome: nested study.

OBJECTIVE Neurally adjusted ventilatory assist (NAVA) is a new ventilator modality with an innovative synchronization technique. Our aim is to verify if NAVA is feasible and safe in terms of physiological and clinical variables in infants recovering from severe acute respiratory distress syndrome (ARDS). DESIGN This is a pilot nested study to help future trial design. SETTING The study was performed in third-level academic pediatric intensive care units. PATIENTS Infants affected by severe ARDS requiring high-frequency ventilation and weaned with NAVA during 2010 were included. Controls (2:1 ratio) were ARDS infants weaned with pressure support ventilation (PSV) during 2008-2009 matched for age, gas exchange impairment, and weight. MAIN OUTCOME MEASURES The main outcome measures were the physiological and ventilator parameters and the duration of ventilator support in PSV or NAVA. RESULTS Ten infants treated with NAVA and 20 with PSV were studied. Heart rate (P < .001) and mean arterial pressure (P < .001) increased less during NAVA than during PSV. Similarly, Pao2/Fio2 ratio decreased less in NAVA than in PSV (P < .001). Neurally adjusted ventilatory assist also resulted in lower Paco2 (P < .001) and peak pressure (P = .001), as well as higher minute ventilation (P = .013). COMFORT score (P = .004) and duration of support were lower in NAVA than in PSV (P = .011). CONCLUSIONS Neurally adjusted ventilatory assist is safe and suitable in infants recovering from severe ARDS. It could provide better results than PSV and is worth to be investigated in a multicenter randomized trial.

Sonographic assessment of abdominal vein dimensional and hemodynamic changes induced in human volunteers by a model of abdominal hypertension.

Objective:In patients affected by intra-abdominal hypertension, bladder or gastric pressure measurement may be usefully integrated by ultrasounds in order to detect early hemodynamic impairment. The purpose of this study was to search for changes in abdominal vein size and flow induced by intra-abdominal hypertension. Design:Physiologic study. Setting:Postoperative intensive care unit of a university hospital. Subjects:Sixteen healthy volunteers. Interventions:Four echographic assessments of vessel sizes and blood velocities were randomly performed in the following settings: 1) baseline, 2) intra-abdominal hypertension simulated by a tight pelvic stabilizer around the waist, 3) noninvasive ventilation with a facial mask, and 4) intra-abdominal hypertension plus noninvasive ventilation. Measurements and Main Results:The model of intra-abdominal hypertension was validated in eight subjects by measuring gastric pressure. During intra-abdominal hypertension, 1) the inferior vena cava was compressed (significant decrease of both anteroposterior and lateral diameters) and deformed (decreased anteroposterior/lateral diameter ratio), and deformation, but not compression, was attenuated by noninvasive ventilation associated with intra-abdominal hypertension; 2) the portal vein was also compressed (decreased diameter); and 3) blood velocities did not change significantly in the inferior vena cava, portal vein, right suprahepatic vein, or right external iliac vein. In the receiver operating characteristic curve analysis, an inferior vena cava section area (normalized for body surface) of lower than 1 cm2/m2 discriminated between intra-abdominal hypertension presence and absence with a sensitivity of 65.6% and a specificity of 87.5% (p = .0001). Noninvasive ventilation alone did not significantly affect vein sizes and velocities. The resistive index, calculated by pulse wave Doppler signal from segmental branches of the right renal artery, increased slightly, but significantly, during intra-abdominal hypertension alone, suggesting an increase of intrarenal pressure. Conclusions:Simulated intra-abdominal hypertension was associated with decreased inferior vena cava section area and increased resistive index in renal arteries. Further studies are now needed to investigate whether these changes may be of value to integrate bladder or gastric pressure measurement in clinical practice.

How to make the axillary vein larger? Effect of 90° abduction of the arm to facilitate ultrasound-guided axillary vein puncture ☆

PURPOSE Placement of central venous catheters by the infraclavicular route can be achieved by ultrasound-guided puncture of the axillary vein. However, in some cases, the axillary vein may be difficult to puncture because it is too deep or too small or because it is collapsing significantly during breathing. The objective of this observational study was to determine the effect of 90° abduction of the arm associated with forward position of the shoulder on axillary vein diameters. MATERIAL AND METHODS In a group of 30 healthy volunteers and in a group of 40 patients during spontaneous breathing, we used ultrasound to examine the axillary vein, visualizing it in short axis, with the arm at 0° and at 90° abduction, pushing the shoulder forward. RESULTS The axillary vein was easily identified in 100% of subjects, with relevant variability in terms of depth from the skin, diameter, and tendency to collapse during inspiration. Significant increase of axillary vein diameters was found after 90° abduction in 52 of the 70 cases studied. CONCLUSION These findings suggest that a 90° abduction of the arm, particularly if associated with a forward position of the shoulder, facilitates the visualization of the axillary vein, making its ultrasound-guided venipuncture easier.

Point-of-care pleural and lung ultrasound in a newborn suffering from cardiac arrest due to tension pneumothorax after cardiac surgery

We report the case of a 12-day-old newborn affected by coarctation of the aorta and intraventricular defect who underwent coarctectomy and pulmonary artery banding. On post-operative day 7, the patient suffered from pulseless electric activity due to tension pneumothorax. Point-of-care ultrasound was performed during cardiopulmonary resuscitation in an attempt to diagnose pneumothorax. The diagnosis was made without delaying or interrupting chest compressions, and the pneumothorax was promptly treated.

Sonographic dynamic assessment of lung injury in a child with hypoplastic left heart syndrome undergoing extracorporeal membrane oxygenation

Performed for many years in clinical settings, pleural and lung ultrasound (PLUS) has emerged to be an invaluable tool to diagnose underlying conditions of respiratory failure, to monitor disease progression and to ensure appropriate therapeutic intervention. PLUS basically relies on the analysis of two prevalent ultrasound artefacts: A‐lines and B‐lines. A‐lines are hyperechoic reverberation artefacts of the pleural line. A‐lines combined with lung sliding show that lungs are well aerated. B‐lines are vertical hyperechoic reverberation artefacts arising from pleural line extending to the bottom of the screen. The prevalence of B‐lines indicates a pathologic parenchyma. Since PLUS is readily available, easily affordable, and biologically non‐invasive, it is especially suitable for bedside clinical care in critically ill and unstable adult patients. Several authors have recently proposed PLUS for application in critically ill neonates and children. We report a case in which PLUS was used to clinically monitor a complex lung lesion during treatment of a child with congenital heart disease suffering from severe lung injury.

Ultrasound-Guided Central Venous Catheterization: It Is High Time to Use a Correct Terminology.

To the Editor: We read with interest the article by Vogel et al (1) on ultrasound-guided puncture of internal jugular vein (IJV) and subclavian vein (ScV). In this article, the authors refer to the long-axis (LA) and short-axis (SA) views as “venipuncture” techniques. This is not correct: LA and SA views are sonographic imaging approaches and refer to the relationship between the plane of the probe and the axis of the vessel (Fig. 1). In LA view, the plane of the probe is parallel to the LA of the vein (longitudinal scan, Fig. 1, I and M); in SA view, the plane of the probe is perpendicular to the axis of the vessel (transversal view, Fig. 1, B, D, and G). Venipuncture techniques are defined not only by this spatial relationship between the plane of the probe and the axis of the vein but also by the relationship between the probe and the needle (Fig. 1, A, F, H, and L). Regardless of the vessel view, the needle can be advanced “out-of-plane” (OP), that is, perpendicular to the plane of the probe (Fig. 1F), or “in-plane” (IP), that is, within the plane of the probe (2) (Fig. 1, A, C, E, F, H, and L). Each venipuncture technique should be appropriately defined by the relationship between the probe and the vein (SA or LA) and by the relationship between the probe and the needle (OP or IP). The authors reply: We thank Fan et al (1) for their comments regarding our recently published article (2) and the opportunity to respond. Cardiac surgery–associated acute kidney injury (CSA-AKI) is a phenotypic syndrome likely reflecting a heterogeneous array of pathophysiologic processes occurring in response to a heterogeneous array of biological insults. For any given case, the precise etiology and mechanism of CSA-AKI is seldom if ever known with certainty and likely not restricted to a single mechanism. Therefore, additional subgroup analysis of our data according to etiology of AKI is not practicable. Fan et al (1) additionally suggest that it remains unclear whether neutrophil gelatinase–associated lipocalin (NGAL) shows superior prognostic performance compared with either serum creatinine or the Acute Physiology and Chronic Health Evaluation II (APACHE II) score for unspecified outcomes. Our data meticulously evaluated the prognostic utility of both urinary NGAL and varying creatinine-based metrics, applied at comparable time points after surgery, for the composite outcome of hospital mortality or renal replacement therapy as hard clinical endpoints designed to reflect clinically meaningful renal injury. Prior to 18–24 hours post separation from cardiopulmonary bypass (typically corresponding to the morning of postoperative day 1), we found little evidence that NGAL provided superior prognostic utility compared with novel creatinine-based metrics. However, the combination of urinary NGAL with a novel creatinine-based metric provided excellent prognostic utility for hospital mortality or renal replacement therapy around the time of postoperative admission to the ICU. This novel finding supports the long-held belief that combining biologically different biomarkers may enable better recognition of renal injury than any individual marker used in isolation (3, 4). APACHE II seeks to predict mortality by measuring injury and dysfunction in multiple organs systems, both renal and extrarenal, making a direct comparison of prognostic utility with NGAL inappropriate for the purpose of our study (5). We analyzed urinary NGAL at four separate time points: Baseline, within 1 hour of separating from cardiopulmonary bypass (CPB), 3 hours after separating from CPB (typically around the time of ICU admission), and finally, 18–24 hours post-CPB (typically corresponding to the morning of postoperative day 1). These multiple time points enabled a pragmatic assessment of the temporal variation in utility of NGAL that we believe is more informative than fluctuations in absolute NGAL values. Although an increased frequency of biomarker measurement may have provided additional information, our choice of four time points reflected a necessary balance between adequate information to answer the study question and cost. Finally, multiple other novel biomarkers of renal injury were also evaluated as part of the same study, and we hope to publish details of these analyses in the near future. Dr. McIlroy received support from Elsevier (honorarium for contributing to Renal Chapter—Miller’s Textbook of Anesthesia). His institution received grant support from both the Australia & New Zealand College of Anaesthetists and the Society of Cardiovascular Anesthesiologists for projects separate from the submitted work. Dr. Lee’s institution received multiple National Institutes of Health grants for laboratory research (R01). The remaining authors have disclosed that they do not have any potential conflicts of interest.

Targeting zero catheter-related bloodstream infections in pediatric intensive care unit: a retrospective matched case-control study

Introduction: The aim of this study was to evaluate the effectiveness and safety of a new three-component ‘bundle’ for insertion and management of centrally inserted central catheters (CICCs), designed to minimize catheter-related bloodstream infections (CRBSIs) in critically ill children. Methods: Our ‘bundle’ has three components: insertion, management, and education. Insertion and management recommendations include: skin antisepsis with 2% chlorhexidine; maximal barrier precautions; ultrasound-guided venipuncture; tunneling of the catheter when a long indwelling time is expected; glue on the exit site; sutureless securement; use of transparent dressing; chlorhexidine sponge dressing on the 7th day; neutral displacement needle-free connectors. All CICCs were inserted by appropriately trained physicians proficient in a standardized simulation training program. Results: We compared CRBSI rate per 1000 catheters-days of CICCs inserted before adoption of our new bundle with that of CICCs inserted after implementation of the bundle. CICCs inserted after adoption of the bundle remained in place for a mean of 2.2 days longer than those inserted before. We found a drop in CRBSI rate to 10%, from 15 per 1000 catheters-days to 1.5. Conclusions: Our data suggest that a bundle aimed at minimizing CR-BSI in critically ill children should incorporate four practices: (1) ultrasound guidance, which minimizes contamination by reducing the number of attempts and possible break-down of aseptic technique; (2) tunneling the catheter to obtain exit site in the infra-clavicular area with reduced bacterial colonization; (3) glue, which seals and protects the exit site; (4) simulation-based education of the staff.

Central venous pressure monitoring via peripherally or centrally inserted central catheters: a systematic review and meta-analysis

Introduction The central venous pressure (CVP) is the most commonly used static marker of preload for guiding fluid therapy in critically ill patients, though its usefulness remains controversial. Centrally inserted central catheters (CICCs) are the gold-standard devices for CVP monitoring but peripherally inserted central catheters (PICCs) may represent a valid alternative. We undertook a systematic review and meta-analysis with the aim to investigate whether the difference between PICC- and CICC-measured CVP is not significant. Methods We searched for clinical studies published in PubMed and EMBASE databases from inception until December 21st 2016. We included studies providing data on paired and simultaneous CVP measurement from PICCs and CICCs. We conducted two analyses on the values of CVP, the first one according to the total number of CVP assessments, the second one considering the number of patients recruited. Results Four studies matched the inclusion criteria, but only three of them provided data for the meta-analyses. Both analyses showed non-significant differences between PICC-measured and CICC-measured CVP: 1489 paired simultaneous CVP assessments (MD 0.16, 95%CI −0.14, 0.45, p = 0.30) on a total of 57 patients (MD 0.22, 95%CI −1.46, 1.91, p = 0.80). Both analyses showed no heterogeneity (I2 = 0%). Conclusions Available evidence supports that CVP monitoring with PICCs is accurate and reproduces similar values to those obtained from CICCs. The possibility to monitor CVP should not be used among clinical criteria for preferring a CICC over a PICC line.

Clinical Outcomes and Prognostic Factors for Spontaneous Intracerebral Hemorrhage in Pediatric ICU: A 12-Year Experience

Background: In the pediatric population, spontaneous intracerebral hemorrhage (sICH) is as common as ischemic stroke and accounts for significant mortality and morbidity. Differently from the ischemic stroke, there are few guidelines for directing management of sICH. This article aims to analyze both clinical outcomes and prognostic factors in order to produce tools for the design of prospective randomized studies addressed to implement treatment of pediatric sICH. Methods: Twelve-year retrospective review of a single-center consecutivesICH pediatric cases admitted to the pediatric intensive care unit (PICU). Selected end points were survival, PICU stay, and dichotomized Glasgow Outcome Score (GOS), with recovery and moderate disability (GOS 4-5) classified as favorable outcome and vegetative state or severe disability (GOS 2-3) classified as unfavorable. Results: Data of 107 children younger than 14 years admitted to our PICU due to sICH were analyzed. Overall PICU mortality was 24.2%. On multivariate analysis, the single factor markedly influencing survival was the presence of midline shift (P = .002). In PICU survivors, there were 42 GOS 2-3 and 39 GOS 4-5. A low Glasgow Coma Scale (GCS) on PICU admission was predictive of severe neurological impairment in survivors (P = .003). Intraventricular hemorrhage and infratentorial origin did not influence outcome in this series. Conclusion: The severity of presentation of sICH expressed by the midline shift and the GCS at PICU admission are significant prognostic factors for survival and neurological outcome. Some prognostic factors of the adult population have not been confirmed.

qEEG by neurointensivists: research agenda and implications for training

Initial correspondence from Drs. Biasucci and Caricato Dear Editor, We read with very special interest the paper from Citerio and the CrazyEEG group assessing the feasibility of an intensivist-led 8-channel continuous quantitative electroencephalography (qEEG) monitoring in the neurointensive care unit (NICU) after a standardized training [1]. We have to acknowledge that qEEG is an ideal and promising tool for monitoring seizures and ischemia in the acute phase of cerebral injury being noninvasive and continuous, and allowing to assess both regional and global cerebral condition [2, 3]. Nowadays, development of a standardized and validated training protocol is needed to spread and implement the clinically driven and multimodal monitoring integrated qEEG use for neurointensivists. The published literature on educational methods of EEG instruction is poor with some recommendations for the EEG curriculum, which includes simulation. Fahy and coworkers proposed a training protocol for anesthesiologists including didactic lectures on EEG principles associated with EEG evaluations with an expert neurophysiologist [4]. They found that significant short-term knowledge gain occurred after 10 EEG interpretations with the neurophysiologist teaching trainees in person in a 1:1 faculty-to-trainee ratio, whereas long-term retention of basic knowledge was achieved after 20 EEG interpretations [4]. Regarding continuous qEEG, Citerio and coworkers, as first, evaluated a total of 1740 monitoring hours, which was proven to be effective to achieve competence among a group of qEEG-naïve intensivists with various degrees of NICU experience [1]. In the light of this evidence, we strongly believe that an appropriate educational program should include (a) didactic lectures on basics of monitoring, montages, physiologic basics of EEG, and main clinical applications (symmetry, sedation, artifacts, seizures, ischemia, sleep); (b) laboratory training consisting of at least 20 supervised EEG and qEEG interpretations; and finally, (c) clinical training which should be divided into two parts: the supervised phase including a number of qEEG monitoring hours per trainee which has to be defined, and the personal learning curve at the end of which a clinical audit with the teaching neurophysiologist is needed to verify the competence achieved. In their study, Citerio and coworkers outlined a path which could be the base to address one of the main issues allowing the spread of the proper use of qEEG in NICU. We strongly believe that a consensus on minimal requirements for training on qEEG interpretation by intensivists is needed, and scientific societies should promote standardized training programs on qEEG monitoring.