Quantifying potential fluid transfused through pressure monitoring and circuit flushes in pediatric ECMO patients.

Pressure monitoring on pediatric Extracorporeal Membrane Oxygenation (ECMO) circuits is used to aid in the evaluation of patient hemodynamics and circuit health. Extracorporeal Life Support Organization (ELSO) recommends monitoring pressures on the venous line, pre-, and post-oxygenator. In order to keep pressure ports patent, crystalloid can be used as a flush. The fluid transfused to the patient through these lines can be challenging to quantify accurately due to variance in clinician practice. Currently, there is no published data or practice suggestions on this topic. In Vitro experiments using Edwards True Wave transducers and pressure bags were constructed, allowing for common negative and positive pressures to be simulated. Passive volume infused through the transducer as well as intermittent active flushing by pulling the snap tab were measured and the volumes were recorded. When the pressure transducer and associated tubing are kept patent by using a pressurized IV bag, per the instructions for use, the daily volume transfused was found to be 319.6 mL or close to a typical neonate's total blood volume. Rather than using passive or active flushing, the use of automated syringe pumps can reduce the transfused volume to 24 mL per day. Further study is recommended to develop and publish best practices.

Effect of a Quality Improvement Bundle to Standardize the Use of Intravenous Fluids for Hospitalized Pediatric Patients: A Stepped-Wedge, Cluster Randomized Clinical Trial.

Importance: Given that hypotonic maintenance intravenous fluids (IVF) may cause hospital-acquired harm, in November 2018, the American Academy of Pediatrics released a clinical practice guideline recommending the use of isotonic IVF for patients aged 28 days to 18 years without contraindications. No recommendations were made regarding laboratory monitoring; however, unnecessary laboratory tests may contribute to health care waste and harm patients. Objective: To examine the effect of a quality improvement intervention bundle on (1) increasing the mean proportion of hours per hospital day with exclusive isotonic IVF use to at least 80% and (2) decreasing the mean proportion of hospital days with laboratory tests obtained. Design, Setting, and Participants: This stepped-wedge, cluster randomized clinical trial (Standardization of Fluids in Inpatient Settings [SOFI]) was sponsored by a national quality improvement collaborative and was conducted across 106 US pediatric hospitals. The SOFI intervention period was from September 2019 to March 2020. Interventions: Hospital sites were exposed to educational materials, a clinical algorithm and order set for IVF use, electronic medical record interventions to reduce laboratory testing, and "harms of overtesting" cards. Main Outcomes and Measures: Primary outcomes were mean proportion of hours per hospital day receiving exclusive isotonic IVF and mean proportion of hospital days with laboratory test values obtained. Secondary measures included total IVF duration per hospital day, daily patient weight measurement while receiving IVF, serum sodium testing, and adverse events. Baseline data were collected for 2 months; intervention period data, 7 months. Outcomes were analyzed using linear mixed-effects regression models. Results: A total of 106 hospitals were randomly assigned to 1 of 3 intervention start dates (wedges), and 100 hospitals (94%) completed the study. In total, 5215 hospitalizations were reviewed before the intervention, and 6724 hospitalizations were reviewed after the intervention. Prior to interventions, the mean (SD) proportion of hours per day with exclusive isotonic IVF use was 88.5% (31.7%). Interventions led to an absolute increase of 5.4% (95% CI, 3.9%-6.9%) above baseline in exclusive isotonic IVF use but did not change the proportion of hospital days during which a laboratory test value was obtained (estimated difference, 0.1%; 95% CI, -1.5% to 1.7%; P = .90), IVF use duration (estimated difference, -1.2%; 95% CI, -2.9% to 0.4%), serum sodium testing, or adverse events. There was an absolute increase of 4.4% (95% CI, 2.6%-6.2%) in the mean proportion of hospital days with a patient weight measurement while receiving IVF. Conclusions and Relevance: In this stepped-wedge, cluster randomized clinical trial, an intervention bundle significantly improved the use of isotonic maintenance IVF without a concomitant increase in adverse events or electrolyte testing. Further work is required to deimplement laboratory testing. Trial Registration: ClinicalTrials.gov Identifier: NCT03924674.

Bioelectrical impedance analysis-guided fluid management promotes primary fascial closure after open abdomen: a randomized controlled trial.

BACKGROUND: Fluid overload (FO) after resuscitation is frequent and contributes to adverse outcomes among postinjury open abdomen (OA) patients. Bioelectrical impedance analysis (BIA) is a promising tool for monitoring fluid status and FO. Therefore, we sought to investigate the efficacy of BIA-directed fluid resuscitation among OA patients. METHODS: A pragmatic, prospective, randomized, observer-blind, single-center trial was performed for all trauma patients requiring OA between January 2013 and December 2017 to a national referral center. A total of 140 postinjury OA patients were randomly assigned in a 1:1 ratio to receive either a BIA-directed fluid resuscitation (BIA) protocol that included fluid administration with monitoring of hemodynamic parameters and different degrees of interventions to achieve a negative fluid balance targeting the hydration level (HL) measured by BIA or a traditional fluid resuscitation (TRD) in which clinicians determined the fluid resuscitation regimen according to traditional parameters during 30 days of ICU management. The primary outcome was the 30-day primary fascial closure (PFC) rate. The secondary outcomes included the time to PFC, postoperative 7-day cumulative fluid balance (CFB) and adverse events within 30 days after OA. The Kaplan-Meier method and the log-rank test were utilized for PFC after OA. A generalized linear regression model for the time to PFC and CFB was built. RESULTS: A total of 134 patients completed the trial (BIA, n = 66; TRD, n = 68). The BIA patients were significantly more likely to achieve PFC than the TRD patients (83.33% vs. 55.88%, P < 0.001). In the BIA group, the time to PFC occurred earlier than that of the TRD group by an average of 3.66 days (P < 0.001). Additionally, the BIA group showed a lower postoperative 7-day CFB by an average of 6632.80 ml (P < 0.001) and fewer complications. CONCLUSION: Among postinjury OA patients in the ICU, the use of BIA-guided fluid resuscitation resulted in a higher PFC rate and fewer severe complications than the traditional fluid resuscitation strategy.

Randomized Controlled Trial of Ultrasound-guided Fluid Resuscitation of Sepsis-Induced Hypoperfusion and Septic Shock.

INTRODUCTION: The ultrasound measurement of inferior vena cava (IVC) diameter change during respiratory phase to guide fluid resuscitation in shock patients is widely performed, but the benefit on reducing the mortality of sepsis patients is questionable. The study objective was to evaluate the 30-day mortality rate of patients with sepsis-induced tissue hypoperfusion (SITH) and septic shock (SS) treated with ultrasound-guided fluid management (UGFM) using ultrasonographic change of the IVC diameter during respiration compared with those treated with the usual-care strategy. METHODS: This was a randomized controlled trial conducted in an urban, university-affiliated tertiary-care hospital. Adult patients with SITH/SS were randomized to receive treatment with UGFM using respiratory change of the IVC (UGFM strategy) or with the usual-care strategy during the first six hours after emergency department (ED) arrival. We compared the 30-day mortality rate and other clinical outcomes between the two groups. RESULTS: A total of 202 patients were enrolled, 101 in each group (UGFM vs usual-care strategy) for intention-to-treat analysis. There was no significant difference in 30-day overall mortality between the two groups (18.8% and 19.8% in the usual-care and UGFM strategy, respectively; p > 0.05 by log rank test). Neither was there a difference in six-hour lactate clearance, a change in the sequential organ failure assessment score, or length of hospital stay. However, the cumulative fluid amount given in 24 hours was significantly lower in the UGFM arm. CONCLUSION: In our ED setting, the use of respiratory change of IVC diameter determined by point-of-care ultrasound to guide initial fluid resuscitation in SITH/SS ED patients did not improve the 30-day survival probability or other clinical parameters compared to the usual-care strategy. However, the IVC ultrasound-guided resuscitation was associated with less amount of fluid used.

Remote-Controlled and Pulse Pressure-Guided Fluid Treatment for Adult Patients with Viral Hemorrhagic Fevers.

Circulatory shock, caused by severe intravascular volume depletion resulting from gastrointestinal losses and profound capillary leak, is a common clinical feature of viral hemorrhagic fevers, including Ebola virus disease, Marburg hemorrhagic fever, and Lassa fever. These conditions are associated with high case fatality rates, and they carry a significant risk of infection for treating personnel. Optimized fluid therapy is the cornerstone of management of these diseases, but there are few data on the extent of fluid losses and the severity of the capillary leak in patients with VHFs, and no specific guidelines for fluid resuscitation and hemodynamic monitoring exist. We propose an innovative approach for monitoring VHF patients, in particular suited for low-resource settings, facilitating optimizing fluid therapy through remote-controlled and pulse pressure-guided fluid resuscitation. This strategy would increase the capacity for adequate supportive care, while decreasing the risk for virus transmission to health personnel.

Accuracy of fluid delivery devices for the neonate: Are the measures assured?

INTRODUCTION: Delivery of accurate volumes of fluid in surgical neonates and children is crucial for the good outcome of treatment. But how accurate are the calibrations on the fluid delivery devices? AIMS: This study seeks to verify the accuracy of these devices in common use in our practice. MATERIALS AND METHODS: This is a cross-sectional experimental study carried out in our center; a tertiary health facility in Southern Nigeria in May 2019. Fluid delivery devices (FDDs) used in the course of treatment of our pediatric patients were randomly included in the study. The number of drops per ml of each device was obtained by counting while the fluid dropped until a 1 ml volume was delivered. The data was then collated and analyzed. RESULTS: A total of 215 FDDs were included in this study. They comprised infusion giving set, Soluset (Burette) giving set, and blood giving set. The rate of delivery was 20 drops/ml (infusion giving sets), 60 drops/min (Burette/Soluset), and 15 drops/ml (Blood giving set). They were all in keeping with the labeled/assumed calibration in each of the types of FDDs P < 0.05. Therefore, the mean, median, and mode were the same. CONCLUSION: This study has demonstrated that the FDDs used our center are accurately calibrated and safe as they deliver volumes of fluid as labeled. The findings in this study reassure us of the dependability and accuracy of delivery of the FDDs we use in children in our center.

Device Based Approaches to the Prevention of Contrast-Induced Acute Kidney Injury.

Contrast-induced acute kidney injury is not uncommon after percutaneous coronary intervention, particularly in high-risk patients. Pharmacologic approaches have not demonstrated significant benefit, and numerous device-based approaches exist targeting a variety of pathways. In this review, we summarize the most recent interventions and the evidence behind them.

Variability in usual care fluid resuscitation and risk-adjusted outcomes for mechanically ventilated patients in shock.

RATIONALE: There remains significant controversy regarding the optimal approach to fluid resuscitation for patients in shock. The magnitude of care variability in shock resuscitation, the confounding effects of disease severity and comorbidity, and the relative impact on sepsis survival are poorly understood. OBJECTIVE: To evaluate usual care variability and determine the differential effect of observed and predicted fluid resuscitation volumes on risk-adjusted hospital mortality for mechanically ventilated patients in shock. METHODS: We performed a retrospective outcome analysis of mechanically ventilated patients admitted to intensive care units using the 2013 Premier Hospital Database (Premier, Inc.). Observed and predicted hospital mortality were evaluated by observed and predicted day 1 fluid administration, using the difference in predicted and observed outcomes to adjust for disease severity between groups. Both predictive models were validated using a second large administrative database (Truven Health Analytics Inc.). Secondary outcomes included duration of mechanical ventilation, hospital and ICU length of stay, and cost. RESULTS: Among 33,831 patients, observed hospital mortality was incrementally higher than predicted for each additional liter of day 1 fluid beginning at 7 L (40.9% vs. 37.2%, p = 0.008). Compared to patients that received expected (± 1.5 L predicted) day 1 fluid volumes, greater-than-expected fluid resuscitation was associated with increased risk-adjusted hospital mortality (52.3% vs. 45.0%, p < 0.0001) among all patients with shock and among a subgroup of shock patients with comorbid conditions predictive of lower fluid volume administration (47.1% vs. 41.5%, p < 0.0001). However, in patients with shock but without such conditions, both greater-than-expected (57.5% vs. 49.2%, p < 0.0001) and less-than-expected (52.1% vs. 49.2%, p = 0.037) day 1 fluid resuscitation were associated with increased risk-adjusted hospital mortality. CONCLUSIONS: Highly variable day 1 fluid resuscitation was associated with a non-uniform impact on risk-adjusted hospital mortality among distinct subgroups of mechanically ventilated patients with shock. These findings support closer evaluation of fluid resuscitation strategies that include broadly applied fluid volume targets in the early phase of shock resuscitation.

Systematic assessment of fluid responsiveness during early septic shock resuscitation: secondary analysis of the ANDROMEDA-SHOCK trial.

BACKGROUND: Fluid boluses are administered to septic shock patients with the purpose of increasing cardiac output as a means to restore tissue perfusion. Unfortunately, fluid therapy has a narrow therapeutic index, and therefore, several approaches to increase safety have been proposed. Fluid responsiveness (FR) assessment might predict which patients will effectively increase cardiac output after a fluid bolus (FR+), thus preventing potentially harmful fluid administration in non-fluid responsive (FR-) patients. However, there are scarce data on the impact of assessing FR on major outcomes. The recent ANDROMEDA-SHOCK trial included systematic per-protocol assessment of FR. We performed a post hoc analysis of the study dataset with the aim of exploring the relationship between FR status at baseline, attainment of specific targets, and clinically relevant outcomes. METHODS: ANDROMEDA-SHOCK compared the effect of peripheral perfusion- vs. lactate-targeted resuscitation on 28-day mortality. FR was assessed before each fluid bolus and periodically thereafter. FR+ and FR- subgroups, independent of the original randomization, were compared for fluid administration, achievement of resuscitation targets, vasoactive agents use, and major outcomes such as organ dysfunction and support, length of stay, and 28-day mortality. RESULTS: FR could be determined in 348 patients at baseline. Two hundred and forty-two patients (70%) were categorized as fluid responders. Both groups achieved comparable successful resuscitation targets, although non-fluid responders received less resuscitation fluids (0 [0-500] vs. 1500 [1000-2500] mL; p 0.0001), exhibited less positive fluid balances, but received more vasopressor testing. No difference in clinically relevant outcomes between FR+ and FR- patients was found, including 24-h SOFA score (9 [5-12] vs. 8 [5-11], p = 0.4), need for MV (78% vs. 72%, p = 0.16), need for RRT (18% vs. 21%, p = 0.7), ICU-LOS (6 [3-11] vs. 6 [3-16] days, p = 0.2), and 28-day mortality (40% vs. 36%, p = 0.5). Only thirteen patients remained fluid responsive along the intervention period. CONCLUSIONS: Systematic assessment allowed determination of fluid responsiveness status in more than 80% of patients with early septic shock. Fluid boluses could be stopped in non-fluid responsive patients without any negative impact on clinical relevant outcomes. Our results suggest that fluid resuscitation might be safely guided by FR assessment in septic shock patients. TRIAL REGISTRATION: ClinicalTrials.gov identifier, NCT03078712. Registered retrospectively on March 13, 2017.

Comparison of the trometamol-balanced solution with two other crystalloid solutions for fluid resuscitation of a rat hemorrhagic model.

Currently, the optimal resuscitation fluid remains debatable. Therefore, in the present study, we designed a trometamol-balanced solution (TBS) for use as a resuscitation fluid for hemorrhagic shock. Hemorrhagic shock was induced in 18 male Wistar-Kyoto rats, which were assigned to normal saline (NS), Ringer's solution (RS), and TBS groups. During the hemorrhagic state, their hemodynamic parameters were recorded using an Abbott i-STAT analyzer with the CG4+ cartridge (for pH, pressure of carbon dioxide, pressure of oxygen, total carbon dioxide, bicarbonate, base excess, oxygen saturation, and lactate), the CG6+ cartridge (for sodium, potassium, chloride, blood glucose, blood urea nitrogen, hematocrit, and hemoglobin), and enzyme-linked immunosorbent assay kits (calcium, magnesium, creatinine, aspartate aminotransferase, alanine aminotransferase, bilirubin, and albumin). Similar trends were found for the parameters of biochemistries, electrolytes, and blood gas, and they revealed no significant changes after blood withdrawal-induced hemorrhagic shock. However, the TBS group showed more effective ability to correct metabolic acidosis than the NS and RS groups. TBS was a feasible and safe resuscitation solution in this study and may be an alternative to NS and RS for resuscitation in hemorrhagic shock patients without liver damage.

Determination of the Pretibial Soft Tissue Thickness in Children: Are Intraosseous Infusion Needles Long Enough?

OBJECTIVE: The EZ-IO intraosseous (IO) needle is available in 2 needle sizes for children based on the patient weight. To date, there is no published evidence validating the use of weight-based scaling in children. We hypothesized that pretibial subcutaneous tissue thickness (PSTT) does not correspond with patient weight but rather with age and body mass index (BMI). Our objective was to describe the relationship of a patient's PSTT to their weight, age, and BMI in children less than 40 kg. METHOD: One hundred patients who weighed less than 40 kg were recruited prospectively from October 2013 to April 2015 at a tertiary care pediatric emergency department. All sonographic assessments were performed by 1 of 2 emergency physicians certified in point-of-care ultrasound. A single sonographic image was taken over the proximal tibia corresponding to the site of IO insertion. In patients where both sonographers performed independent measurements, a Pearson correlation coefficient was determined. Univariate linear regression was performed to determine the relationship between age, weight, and BMI with PSTT. RESULTS: One hundred participants were recruited and ranged in age from 10 days to 14 years (mean [SD], 5.01 [3.14] years). Fifty-seven percent of participants were male. Patients' weights ranged from 3.5 to 39.3 kg (mean [SD], 21.42 [9.12] kg), and BMI ranged from 12.1 to 45.0 kg/m (mean [SD], 17.31 [4.00]). The mean (SD) PSTT across participants was 0.68 (0.2) cm. The intraclass correlation coefficient for agreement between the 2 sonographers was moderate (intraclass correlation coefficient, 0.602 [confidence interval, 0.385-0.757]). There were significant positive correlations between BMI and PSTT (r = 0.562, P = <0.001) as well as weight and PSTT (r = 0.293, P < 0.003). There was a weak correlation between age and PSTT (0.065, P = 0.521). CONCLUSIONS: Pretibial subcutaneous tissue thickness correlates most strongly with BMI, followed by weight, and weakly with age. Our findings suggest that current IO needle length recommendations should be based on BMI rather than weight. This would suggest that clinicians need to be aware that young patients in particular with large BMIs may pose problems with current weight-based needle length recommendations.

Compartment Syndrome of the Leg after Intraosseous (IO) Needle Insertion.

Intraosseous (IO) needles are used in patients who are critically ill when it is not possible to obtain venous access. While IO allows for immediate access, IO infusions are associated with complications including fractures, infections, and compartment syndrome. We present a case of an 87-year-old man who developed lower extremity compartment syndrome after receiving an IO needle insertion and had to be treated surgically with fasciotomy to correct the problem.

Efficacy of Rapid Fluid Administration Using Various Setups and Devices.

OBJECTIVES: In clinical practice, there are various methods that can be used for the rapid administration of fluid in infants and children. The current study prospectively evaluates gravity, pressure-assisted, and hand-pump methods for the rapid administration of fluid using an in vitro model. METHODS: Thirty participants were asked to deliver 500 mL of fluid using 1 of 6 setups: (1) standard blood tubing with gravity administration, (2) standard blood tubing with pressure bag maintained at 300 mm Hg, (3) standard blood tubing with pressure bag inflated to 300 mm Hg and left to flow, (4) blood tubing with in-line bulb pump, (5) blood tubing with in-line bulb pump and pressure bag, and (6) standard blood tubing with 20-mL syringe attached to the stopcock for a push-and-pull technique using a 20-mL syringe. RESULTS: The blood tubing with an in-line bulb pump to allow manual acceleration of the administration of fluid along with a pressure bag on the intravenous fluid bag achieved the fastest flow rate, requiring an average of 98 seconds to deliver 500 mL of fluid. CONCLUSIONS: When considering factors that affect fluid administration, Poiseuille's law dictates that the most important variable is the radius of the intravenous cannula, whereas the length of the cannula and the viscosity of the fluid administered are of secondary importance. With these limitations in mind, other factors may be used to speed fluid administration. Our study demonstrates the advantage of using blood tubing with the in-line bulb pump combined with a pressure bag.

Controlled decongestion by Reprieve therapy in acute heart failure: results of the TARGET-1 and TARGET-2 studies.

AIMS: Safe and effective decongestion is the main goal of therapy in acute heart failure (AHF). In the non-randomized, prospective TARGET-1 and TARGET-2 studies (NCT03897842), we investigated whether adding the Reprieve System® (which continuously monitors urine output and delivers a matched volume of hydration fluid sufficient to maintain the set fluid balance rate) to standard diuretic-based regimen improves decongestion in AHF. METHODS AND RESULTS: The population consisted of 19 patients hospitalized with AHF (mean age 67 ± 10 years, 18 male, ejection fraction 34 ± 15%, median N-terminal pro-B-type natriuretic peptide 4492 pg/mL). Patients served as their own controls: each patient underwent 24 h of standard diuretic therapy followed by 24 h of diuretics with Reprieve therapy (with normal saline used for matched volume replacement). The primary efficacy endpoint of actual fluid loss not exceeding the target fluid loss at the end of therapy was met in all 19 (100%) patients. The mean diuresis during Reprieve therapy was 6284 ± 2679 mL (vs. 1966 ± 1057 mL 24 h before therapy) and 2053 ± 888 mL (24 h after therapy) (both P < 0.0001). At the end of therapy, patient global assessment improved from 7.7 ± 1.1 to 3.0 ± 1.3 points (P < 0.001), central venous pressure decreased from 15.5 ± 5.3 mmHg to 12.8 ± 4.8 mmHg (P < 0.05) and the median urine sodium loss was 9.7 [3-13] mmol/h. The Reprieve therapy was safe, systolic blood pressure remained stable, mean creatinine dropped from 1.45 ± 0.4 mg/dL to 1.26 ± 0.4 mg/dL (P < 0.001) and biomarkers of renal injury did not change during treatment. CONCLUSIONS: The Reprieve System in conjunction with diuretic therapy supports safe and controlled decongestion in AHF.

Emerging Mobile Platforms to Aid in Stone Management.

Nephrolithiasis is an increasingly common condition worldwide and mobile technology is revolutionizing how patients with kidney stone are being diagnosed and managed. Emerging platforms include software applications to increase adherence to stone prevention, mobile compatible hardware, online social media communities, and telemedicine. Applications and hardware specifically relevant to increasing hydration, diet modification, medication adherence, and rapid diagnosis (ie, mobile ultrasound and endoscopy) have the greatest potential to reduce stone recurrence and expedite treatment. Social media and online communities have also been rapidly adopted by patients and providers to promote education and support.

Machine learning for the prediction of volume responsiveness in patients with oliguric acute kidney injury in critical care.

BACKGROUND AND OBJECTIVES: Excess fluid balance in acute kidney injury (AKI) may be harmful, and conversely, some patients may respond to fluid challenges. This study aimed to develop a prediction model that can be used to differentiate between volume-responsive (VR) and volume-unresponsive (VU) AKI. METHODS: AKI patients with urine output < 0.5 ml/kg/h for the first 6 h after ICU admission and fluid intake > 5 l in the following 6 h in the US-based critical care database (Medical Information Mart for Intensive Care (MIMIC-III)) were considered. Patients who received diuretics and renal replacement on day 1 were excluded. Two predictive models, using either machine learning extreme gradient boosting (XGBoost) or logistic regression, were developed to predict urine output > 0.65 ml/kg/h during 18 h succeeding the initial 6 h for assessing oliguria. Established models were assessed by using out-of-sample validation. The whole sample was split into training and testing samples by the ratio of 3:1. MAIN RESULTS: Of the 6682 patients included in the analysis, 2456 (36.8%) patients were volume responsive with an increase in urine output after receiving > 5 l fluid. Urinary creatinine, blood urea nitrogen (BUN), age, and albumin were the important predictors of VR. The machine learning XGBoost model outperformed the traditional logistic regression model in differentiating between the VR and VU groups (AU-ROC, 0.860; 95% CI, 0.842 to 0.878 vs. 0.728; 95% CI 0.703 to 0.753, respectively). CONCLUSIONS: The XGBoost model was able to differentiate between patients who would and would not respond to fluid intake in urine output better than a traditional logistic regression model. This result suggests that machine learning techniques have the potential to improve the development and validation of predictive modeling in critical care research.

What is the lowest change in cardiac output that transthoracic echocardiography can detect?

BACKGROUND: In critically ill patients, changes in the velocity-time integral (VTI) of the left ventricular outflow tract, measured by transthoracic echocardiography (TTE), are often used to non-invasively assess the response to fluid administration or for performing tests assessing fluid responsiveness. However, the precision of TTE measurements has not yet been investigated in such patients. First, we aimed at assessing how many measurements should be averaged within one TTE examination to reach a sufficient precision for various variables. Second, we aimed at identifying the least significant change (LSC) of these variables between successive TTE examinations. METHODS: We prospectively included 100 haemodynamically stable patients in whom TTE examination was planned. Three TTE examinations were performed, the first and the third by one operator and the second by another one. We calculated the precision and LSC (1) within one examination depending on the number of averaged measurements and (2) between measurements performed in two successive examinations. RESULTS: In patients in sinus rhythm, averaging three measurements within an examination was enough for obtaining an acceptable precision (interquartile range highest value < 10%) for VTI. In patients with atrial fibrillation, averaging five measurements was necessary. The precision of some other common TTE variables depending on the number of measurements is provided. Between two successive examinations performed by the same operator, the LSC was 11 [5-18]% for VTI. If two operators performed the examinations, the LSC for VTI significantly increased to 14 [8-26]%. The LSC between two examinations for other TTE variables is also provided. CONCLUSIONS: Averaging three measurements within one TTE examination is enough for obtaining precise measurements for VTI in patients in sinus rhythm but not in patients with atrial fibrillation. Between two TTE examinations performed by the same operator, the LSC of VTI is compatible with the assessment of the effects of a 500-mL fluid infusion but is not precise enough for assessing the effects of some tests predicting preload responsiveness.

Resuscitation Fluid Choices to Preserve the Endothelial Glycocalyx.

This article is one of ten reviews selected from the Annual Update in Intensive Care and Emergency Medicine 2019. Other selected articles can be found online at https://www.biomedcentral.com/collections/annualupdate2019 . Further information about the Annual Update in Intensive Care and Emergency Medicine is available from http://www.springer.com/series/8901 .

IV DripAssist: An Innovative Way to Monitor Intravenous Infusions Away From an Outlet?

Intravenous (IV) administration of fluids and medications are a significant part of patient treatment. In austere environments, typical methods of counting drops from gravity drips or infusion pumps both have limitations such as accuracy, weight, and need for power. The DripAssist device calculates drip rates by counting drops in IV tubing drip chambers and may provide a useful patient safety monitor adjunct. The protocol was IRB approved, prospective, and designed as a pilot study involving 28 Madigan Army Medical Center Emergency Department personnel. After a brief didactic introduction to the device for clinical staff with no prior experience using the device, participants were timed setting three normal saline infusions at rates of 250 mL/h, 125 mL/h and 83 mL/h with 15gtt/mL tubing. Participants filled out a survey on perceived ease of use and utility of the device compared to pumps and manual counting. Most participants felt the DripAssist device was easy to understand and set up, but nurses and physician assistants were more likely than medics to perceive a benefit versus IV pumps or gravity drips. The DripAssist device may offer a safe, low-weight, functional tool which could improve care in a variety of resource-limited environments. However, additional studies using the device during actual field exercises would be beneficial.