Characterization of a murine model of cardiorenal syndrome type 1 by high-resolution Doppler sonography

Abstract

Cardiorenal syndrome type 1 (CRS-1) is the acute kidney disfunction caused by an acute worsening of cardiac function. CRS-1 is the consequence of renal vasoconstriction secondary to renin–angiotensin system (RAS) activation. No animal models of CRS-1 are described in literature.

Purpose

To characterize a murine model of CRS-1 by using a high-resolution ultrasound echo-color Doppler system (VEVO2100).

Materials

Post-ischemic heart failure was induced by coronary artery ligation (LAD) in seven CD1 mice. Fifteen and thirty days after surgery, mice underwent cardiac and renal echo-color Doppler. Serum creatinine and plasma renin activity were measured after killing. Animals were compared to seven CD1 control mice.

Results

Heart failure with left ventricle dilatation (end diastolic area, p < 0.05 vs. controls) and significantly reduced ejection fraction (EF; p < 0.01 vs. controls) was evident 15 days after LAD. We measured a significant renal vasoconstriction in infarcted mice characterized by increased renal pulsatility index (PI; p < 0.05 vs. controls) associated to increased creatinine and renin levels (p < 0.05 vs. controls)

Conclusions

The mice model of LAD is a good model of CRS-1 evaluable by Doppler sonography and characterized by renal vasoconstriction due to the activation of the renin–angiotensin system secondary to heart failure.     

Nonalcoholic fatty liver disease (NAFLD) in nonobese patients with diabetes: Prevalence and relationships with hemodynamic alterations detected with Doppler sonography

Aim

To evaluate the prevalence, severity, and hemodynamic features of nonalcoholic fatty liver disease (NAFLD) in nonobese diabetics.

Methods

We studied 100 consecutive nonobese (body mass index [BMI] < 30) patients with type 1 (n = 17) or type 2 (n = 83) diabetes and no known causes of liver disease. Steatosis was diagnosed and graded with ultrasonography. Digital sonographic images of the liver and right kidney were analyzed with dedicated software (HDI-Lab), and the liver/kidney ratio of grey-scale intensity was calculated as an index of the severity of the steatosis. Severity scores ranging from 0 (none) to 5 (severe) were compared with sonographic and Doppler findings (right liver size, portal vein diameter and flow velocity, hepatic and splenic arterial pulsatility indices, hepatic-vein flow profile and A- and S-wave velocities).

Results

The prevalence of steatosis was 24% in type I and 80% in type II diabetes (grade 1 in 17%, grade 2 in 34%, grade 3 in 33%, grade 4 in 9%, grade 5 in 7%). In patients with steatosis (especially those with grades 4–5 disease), hepatic volume was increased (p < 0.005). Portal vein diameter was increased in grade 5 steatosis. The hepatic artery pulsatility index was significantly increased, particularly in grades 4 and 5 (p < 0.0001); portal and A-wave velocities were significantly reduced in grades 3–5 (p < 0.001); and the hepatic vein flow profile was altered in 27% (biphasic: 20%, flat: 7%) patients with steatosis, although there was no correlation with severity.

Conclusions

NAFLD is very frequent in nonobese diabetics with type 2 but not type 1 disease, and it is associated with hepatomegaly and liver hemodynamic alterations only when it is severe.     

Contrast-enhanced ultrasound with SonoVue in the evaluation of postoperative complications in pediatric liver transplant recipients

Purpose

To evaluate the utility of contrast-enhanced sonography in the study of pediatric liver transplant recipients and its potential impact in reducing the need for invasive diagnostic procedures.

Materials and methods

From October 2002 to December 2003 we performed routine color Doppler ultrasound and contrast-enhanced ultrasound studies on 30 pediatric patients who had undergone liver transplantation. Findings indicative of complications were confirmed with invasive studies (angiography, computed tomography, and PTC).

Results

Contrast-enhanced sonography correctly identified four of the five cases of hepatic artery thrombosis and all those involving the portal (n = 6) and hepatic vein (n = 3) thrombosis. It failed to identify one case of hepatic artery thrombosis characterized by collateral circulation arising from the phrenic artery and the single case of hepatic artery stenosis. The latter was more evident on color Doppler, which revealed a typical tardus parvus waveform. The use of contrast offered no significant advantages in the study of biliary complications although it did provide better visualization of bile leaks.

Conclusions

Contrast-enhanced sonography improves diagnostic confidence and reduces the need for more invasive imaging studies in the postoperative follow-up of pediatric liver transplant recipients.     

Power Doppler sonography to predict the risk of surgical recurrence of Crohn’s disease

Purpose

The aim of this work is to investigate the role of power Doppler sonography as an additional predictor of surgical recurrence in Crohn’s disease.

Methods

A sample of 33 patients, with ileal or ileocolonic Crohn’s disease, that had underwent intestinal resection, were retrospectively enrolled. All patients had bowel ultrasonography 7–16 months after resection. Power Doppler sonography of the preanastomotic ileum was evaluated as a possible prognostication tool to assess the risk of long-term need for reoperation.

Results

The absolute incidence of surgical recurrence in those who had a positive power Doppler was 42 %, while that of those who had a negative power Doppler was 28.6 %. Combining the power Doppler with bowel wall thickness, the surgical recurrence risk grew from 41.2 % of those with a positive power Doppler and thickness >3 mm to 55.6 % of those with a positive power Doppler and thickness >6 mm.

Conclusions

Power Doppler look to be another useful prediction tool for the personalization of patient’s care. It could be useful to perform power Doppler in all patients with a wall thickness >5 mm: for those who have a positive power Doppler it may be indicated as a more aggressive prophylactic therapy.     

Effect of microbubble contrast on intracranial blood flow velocity assessed by transcranial Doppler

Purpose

Ultrasound contrast agents (UCA) salvage a considerable number of transcranial Doppler (TCD) exams which would have failed because of poor bone window. UCA bolus injection causes an undesirable increase in measured blood flow velocity (BFV). The effect of UCA continuous infusion on measured BFV has not been investigated, and some in vitro experiments suggest that gain reduction during UCA administration may also influence measured BFV. This study aimed to investigate the effect of UCA continuous infusion on BFV measured by TCD and the influence of gain reduction on these measurements in a clinical setting.

Methods

The right middle cerebral artery of ten patients with optimal bone window was insonated using a 2 MHz probe. UCA were administered using an infusion pump. BFV was measured (1) at baseline, (2) during UCA infusion, (3) during UCA infusion with gain reduction, and (4) after UCA wash-out phase. Gain reduction was based on the agreement between two neurosonographers on the degree of gain reduction necessary to restore baseline Doppler signal intensity (DSI). Actual DSI was estimated offline by analysis of raw data.

Results

BFV measured during UCA infusion with no gain adjustment was significantly higher than baseline BFV [peak systolic velocity (PSV): 85.1 ± 19.7 vs. 74.4 ± 19.7 cm/s, p < 0.0001; Mean velocity (MV): 56.5 ± 11.8 vs. 50.2 ± 12.3 cm/s, p < 0.0001]. BFV measured during UCA infusion with gain reduction was not significantly higher than baseline BFV (PSV: 74.3 ± 18.9 vs. 74.4 ± 19.4 cm/s, p = 0.8; MV: 49.4 ± 11.0 vs. 50.2 ± 12.3 cm/s, p = 0.8). Actual DSI during UCA infusion with gain reduction was not significantly higher than baseline DSI (13 ± 1 vs. 13 ± 1 dB).

Conclusion

This study shows that UCA continuous infusion leads to an increase in measured BFV which may be counteracted by reducing Doppler gain thus restoring pre-contrast DSI.     

Lipopolysaccharide infusion enhances dynamic cerebral autoregulation without affecting cerebral oxygen vasoreactivity in healthy volunteers

Introduction

Sepsis may be associated with disturbances in cerebral oxygen transport and cerebral haemodynamic function, thus rendering the brain particularly susceptible to hypoxia. The purpose of this study was to assess the impact of isocapnic hypoxia and hyperoxia on dynamic cerebral autoregulation in a human-experimental model of the systemic inflammatory response during the early stages of sepsis.

Methods

A total of ten healthy volunteers were exposed to acute isocapnic inspiratory hyperoxia (F_IO₂ = 40%) and hypoxia (F_IO₂ = 12%) before and after a 4-hour lipopolysaccharide (LPS) infusion (2 ng kg^-1). Middle cerebral artery blood follow velocity was assessed using transcranial Doppler ultrasound, and dynamic autoregulation was evaluated by transfer function analysis.

Results

Transfer function analysis revealed an increase in the phase difference between mean arterial blood pressure and middle cerebral artery blood flow velocity in the low frequency range (0.07–0.20 Hz) after LPS (P<0.01). In contrast, there were no effects of either isocapnic hyperoxia or hypoxia on dynamic autoregulation, and the cerebral oxygen vasoreactivity to both hyperoxia and hypoxia was unaffected by LPS.

Conclusions

The observed increase in phase suggests that dynamic cerebral autoregulation is enhanced after LPS infusion and resistant to any effects of acute hypoxia; this may protect the brain from ischaemia and/or blood–brain barrier damage during the early stages of sepsis.     

Evaluation of 3D blood flow patterns and wall shear stress in the normal and dilated thoracic aorta using flow-sensitive 4D CMR

Background

The purpose of this study was to investigate 3D flow patterns and vessel wall parameters in patients with dilated ascending aorta, age-matched subjects, and healthy volunteers.

Methods

Thoracic time-resolved 3D phase contrast CMR with 3-directional velocity encoding was applied to 33 patients with dilated ascending aorta (diameter ≥40 mm, age=60±16 years), 15 age-matched normal controls (diameter ≤37 mm, age=68±7.5 years) and 15 young healthy volunteers (diameter ≤30 mm, age=23±2 years). 3D blood flow was visualized and flow patterns were graded regarding presence of supra-physiologic-helix and vortex flow using a semi-quantitative 3-point grading scale. Blood flow velocities, regional wall shear stress (WSS), and oscillatory shear index (OSI) were quantified.

Results

Incidence and strength of supra-physiologic-helix and vortex flow in the ascending aorta (AAo) was significantly higher in patients with dilated AAo (16/33 and 31/33, grade 0.9±1.0 and 1.5±0.6) than in controls (2/15 and 7/15, grade 0.2 ± 0.6 and 0.6 ± 0.7, P<.05) or healthy volunteers (1/15 and 0/15, grade 0.1 ± 0.3 P<.05). Greater strength of the ascending aortic helix and vortex flow were associated with significant differences in AAo diameters (P<.05). Peak systolic WSS in the ascending aorta and aortic arch was significantly lower in patients with dilated AAo (P<.0157-.0488). AAo diameter positively correlated to time to peak systolic velocities (r=0.30-0.53, P<.04), OSI (r=0.33-0.49, P<0.02) and inversely correlated to peak systolic WSS (r=0.32-0.40, P<.03). Peak systolic WSS was significantly lower in AAo aneurysms at the right and outer curvature within the AAo and proximal arch (P<.01-.05).

Conclusions

Increase in AAo diameter is significantly correlated with the presence and strength of supra-physiologic-helix and vortex formation in the AAo, as well with decrease in systolic WSS and increase in OSI.     

CEUS in the study of bladder,method, administration and evaluation,a technical note

Purpose

Contrast-enhanced ultrasound (CEUS) is the application of ultrasound contrast agents (UCAs) to traditional medical sonography. The development of UCAs allowed to overcome some of the limitations of conventional B-mode and Doppler ultrasound techniques and enabled the display of the parenchymal microvasculature. Purpose of this paper is to delineate the elements of a solid and science-based technique in the execution of urinary bladder CEUS.

Methods

We describe the technical execution of urinary bladder CEUS and the use of perfusion softwares to perform contrast enhancement quantitative analysis with generation of time–intensity curves from regions of interest.

Results

During CEUS, normal bladder wall shows a wash-in time of 13 s, a time to peak (TTP) >40 s, a signal intensity (SI) <45 % and a wash-out time >80 s; Low-grade urothelial cell carcinoma (UCC) shows a wash-in time of 13 s, a time to peak TTP >28 s, a SI <45 % and a wash-out time of 40 s; High-grade UCC shows a wash-in time of 13 s, a TTP >28 s, a SI >50 % and a wash-out time of 58 s.

Conclusions

CEUS is a useful tool for an accurate characterization of bladder UCC although it has some drawbacks. To avoid misunderstandings, a widely accepted classification and a standardized terminology about the most significant parameters of this application should be adopted in the immediate future.     

Renal arteriovenous fistula simulating hydronephrosis: A case report

Introduction

Acquired renal arteriovenous fistulas (AVFs) include those that occur as a complication of renal biopsy.

Case report

The authors report the case of a woman with recent-onset grade I hypertension, who was referred to our staff for sonographic studies of the kidneys and urinary tract. Laboratory data revealed microhematuria and proteinuria <0.5 g/24 h, and renal function was borderline (MDRD GFR 58 mL/min). Renal sonography of the left kidney revealed an anechoic, arboriform area at the level of the pelvis, which was suggestive of hydronephrosis. The color Doppler examination showed turbulent flow within the anechoic area, with high-velocity arterial flow and arterialization of the venous waveform at spectral analysis. Selective renal angiography later confirmed the presence of a middle renal AVF with pseudoaneurysm, which had been provoked by a renal biopsy performed over 10 years earlier in another center. Since the patient was currently in good health, the prescribed management consisted solely of close clinical and US follow-up.

Discussion

AV fistulas are among the most commonly diagnosed renovascular malformations. The case reported here underlines the importance of using color Doppler ultrasound when obstructive uropathy is suspected, especially in patients who have undergone renal biopsy.     

Sonoelastography findings of biceps tendinitis and tendinosis

Objective

The purpose of this study was to evaluate sonoelastography (SE) in the assessment of the long head of biceps tendon (LHBT) in patients with symptoms of biceps tendinitis or tendinosis and in patients without biceps lesion. The findings were compared with those obtained at clinical examination, using ultrasonography (US).

Materials and methods

36 shoulders of 34 consecutively registered patients with clinical symptoms and US findings of biceps tendinitis or tendinosis, and 114 shoulders of 98 patients without biceps lesions were assessed with SE. Transverse and longitudinal images of LHBT were obtained using SE. SE images were evaluated by reviewers using an experimentally proven color grading system.

Results

The transverse images of SE showed a mean sensitivity of 69.4 %, a mean specificity of 95.6 % and a mean accuracy of 89.3 %. Good correlation of conventional ultrasound findings was found (p < 0.001, r = 0.763). The longitudinal images of SE showed a mean sensitivity of 94.4 %, a mean specificity of 92.1 % and a mean accuracy of 92.7 %. Good correlation of conventional ultrasound findings was found (p < 0.001, r = 0.585). Inter-observer reliability of SE was in “almost perfect agreement” with a weighted kappa coefficient of 0.84.

Conclusions

SE has potential to be clinically useful in the detection of the intratendinous and peritendinous alterations of LHBT and has excellent accuracy and excellent correlation with conventional ultrasound findings.     

The role of intestinal mucosa injury induced by intra-abdominal hypertension in the development of abdominal compartment syndrome and multiple organ dysfunction syndrome

Introduction

Abdominal distension is common in critical illness. There is a growing recognition that intra-abdominal hypertension (IAH) may complicate nonsurgical critical illness as well as after abdominal surgery. However, the pathophysiological basis of the injury to the intestinal mucosal barrier and its influence on the onset of abdominal compartment syndrome (ACS) and multiorgan dysfunction syndrome (MODS) remain unclear. We measured intestinal microcirculatory blood flow (MBF) during periods of raised intra-abdominal pressure (IAP) and examined how this influenced intestinal permeability, systemic endotoxin release, and histopathological changes.

Methods

To test different grades of IAH to the injury of intestinal mucosa, 96 New Zealand white rabbits aged 5 to 6 months were exposed to increased IAP under nitrogen pneumoperitoneum of 15 mmHg or 25 mmHg for 2, 4 or 6 hours. MBF was measured using a laser Doppler probe placed against the jejunal mucosa through a small laparotomy. Fluorescein isothiocyanate (FITC)-conjugated dextran was administered by gavage. Intestinal injury and permeability were measured using assays for serum FITC-dextran and endotoxin, respectively, after each increase in IAP. Structural injury to the intestinal mucosa at different levels of IAH was confirmed by light and transmission electron microscopy.

Results

MBF reduced from baseline by 40% when IAP was 15 mmHg for 2 hours. This doubled to 81% when IAP was 25 mmHg for 6 hours. Each indicator of intestinal injury increased significantly, proportionately with IAP elevation and exposure time. Baseline serum FITC-dextran was 9.30 (± SD 6.00) μg/ml, rising to 46.89 (±13.43) μg/ml after 15 mmHg IAP for 4 hours (P <0.01), and 284.59 (± 45.18) μg/ml after 25 mmHg IAP for 6 hours (P <0.01). Endotoxin levels showed the same pattern. After prolonged exposure to increased IAP, microscopy showed erosion and necrosis of jejunal villi, mitochondria swelling and discontinuous intracellular tight junctions.

Conclusions

Intra-abdominal hypertension can significantly reduce MBF in the intestinal mucosa, increase intestinal permeability, result in endotoxemia, and lead to irreversible damage to the mitochondria and necrosis of the gut mucosa. The dysfunction of the intestinal mucosal barrier may be one of the important initial factors responsible for the onset of ACS and MODS.     

Elevation of cardiac troponin I during non-exertional heat-related illnesses in the context of a heatwave

Introduction

The prognostic value of cardiac troponin I (cTnI) in patients having a heat-related illness during a heat wave has been poorly documented.

Methods

In a post hoc analysis, we evaluated 514 patients admitted to emergency departments during the August 2003 heat wave in Paris, having a core temperature >38.5°C and who had analysis of cTnI levels. cTnI was considered as normal, moderately elevated (abnormality threshold to 1.5 ng.mL^-1), or severely elevated (>1.5 ng.mL^-1). Patients were classified according to our previously described risk score (high, intermediate, and low-risk of death).

Results

Mean age was 84 ± 12 years, mean body temperature 40.3 ± 1.2°C. cTnI was moderately elevated in 165 (32%) and severely elevated in 97 (19%) patients. One-year survival was significantly decreased in patients with moderate or severe increase in cTnI (24 and 46% vs 58%, all P < 0.05). Using logistic regression, four independent variables were associated with an elevated cTnI: previous coronary artery disease, Glasgow coma scale <12, serum creatinine >120 μmol.L^-1, and heart rate >110 bpm. Using Cox regression, only severely elevated cTnI was an independent prognostic factor (hazard ratio 1.93, 95% confidence interval 1.35 to 2.77) when risk score was taken into account. One-year survival was decreased in patients with elevated cTnI only in high risk patients (17 vs 31%, P = 0.04).

Conclusions

cTnI is frequently elevated in patients with non-exertional heat-related illnesses during a heat wave and is an independent risk factor only in high risk patients where severe increase (>1.5 ng.mL^-1) indicates severe myocardial damage.     

Is intraoperative ultrasound (IOUS) still useful for the detection of liver metastases?

Purpose

To evaluate the clinical impact of intraoperative ultrasound (IOUS) in the detection of liver metastases during the years, as compared with those of other imaging modalities.

Materials and methods

All IOUS scans performed for detection of liver metastases from 2000 to 2006 were retrospectively reviewed and compared with the results of preoperative imaging modalities: Ultrasound (US), Computed Tomography (CT), and/or Magnetic Resonance (MR). The number of cases in which IOUS and preoperative imaging studies produced discordant results, in terms of presence/absence of focal liver lesions, was calculated per year. Statistical analysis was performed using the McNemar test. A p value < 0.05 was considered statistically significant.

Results

Eighty-three IOUS scans performed in 2000–2003 were reviewed, and discordance with preoperative imaging findings was found in 19/83 (23%) cases. Of the 42 IOUS scans done during the 2004–2006 period, 10/42 (24%) showed discordance with preoperative studies. All metastases diagnosed with imaging studies were pathologically confirmed. The number of discordant cases in the two periods were not significantly different (p = 0.2).

Conclusion

IOUS is still useful in the detection of liver metastases. Its decreased use is probably due to the improved accuracy of preoperative imaging modalities.     

Effects of thoracic epidural anesthesia on survival and microcirculation in severe acute pancreatitis: a randomized experimental trial

Introduction

Severe acute pancreatitis is still a potentially life threatening disease with high mortality. The aim of this study was to evaluate the therapeutic effect of thoracic epidural anaesthesia (TEA) on survival, microcirculation, tissue oxygenation and histopathologic damage in an experimental animal model of severe acute pancreatitis in a prospective animal study.

Methods

In this study, 34 pigs were randomly assigned into 2 treatment groups. After severe acute pancreatitis was induced by intraductal injection of glycodesoxycholic acid in Group 1 (n = 17) bupivacaine (0.5%; bolus injection 2 ml, continuous infusion 4 ml/h) was applied via TEA. In Group 2 (n = 17) no TEA was applied. During a period of 6 hours after induction, tissue oxygen tension (tpO₂) in the pancreas and pancreatic microcirculation was assessed. Thereafter animals were observed for 7 days followed by sacrification and histopathologic examination.

Results

Survival rate after 7 days was 82% in Group 1 (TEA) versus 29% in Group 2: (Control) (P <0.05). Group 1 (TEA) also showed a significantly superior microcirculation (1,608 ± 374 AU versus 1,121 ± 510 AU; P <0.05) and tissue oxygenation (215 ± 64 mmHg versus 138 ± 90 mmHG; P <0.05) as compared to Group 2 (Control). Consecutively, tissue damage in Group 1 was reduced in the histopathologic scoring (5.5 (3 to 8) versus 8 (5.5 to 10); P <0.05).

Conclusions

TEA led to improved survival, enhanced microcirculatory perfusion and tissue oxygenation and resulted in less histopathologic tissue-damage in an experimental animal model of severe acute pancreatitis.     

Effects of Plum Extract on Skeletal System of Fetal and Newborn Mice

Objective

To evaluate the effects of Prunus domestica L. extracts on fetuses and neonatal skeletal systems.

Materials and Methods

A total of 32 pregnant mice (Mus musculus) received vehicle and plum hydroalcoholic extract at gestational days 1–18 and during the entire gestational period as well as 10 days postpartum, respectively. A total of 30 nonpregnant mice were fed plum hydroalcoholic extract and plum juice extract for 30 days. Bone calcium content and serum concentrations of calcium, magnesium and alkaline phosphatase were measured. The skeletal systems of their fetuses and neonates were stained with Alcian blue and alizarin red S and the length of femur, tibia, and their ossification center were measured.

Results

Crown-rump length of the newborn mice from mothers treated with plum extract (4.61 ± 0.25 mm) was higher compared to the control group (4.48 ± 0.31 mm, p = 0.001), and the femur osteogenesis index of newborn mice from mothers treated with plum extract was also higher (0.87 ± 0.09) compared to the control group (0.81 ± 0.06, p = 0.007).

Conclusion

The findings showed that pregnant mice treated with plum extract had fetuses and newborn mice with higher osteogenesis index than those of the controls.Key Words: Animal models, Bone, Bone mineralization, Fetus, Osteogenesis index, Plum extract, Skeletal system     

Lung protection during non-invasive synchronized assist versus volume control in rabbits

Introduction

Experimental work provides insight into potential lung protective strategies. The objective of this study was to evaluate markers of ventilator-induced lung injury after two different ventilation approaches: (1) a “conventional” lung-protective strategy (volume control (VC) with low tidal volume, positive end-expiratory pressure (PEEP) and paralysis), (2) a physiological approach with spontaneous breathing, permitting synchrony, variability and a liberated airway. For this, we used non-invasive Neurally Adjusted Ventilatory Assist (NIV-NAVA), with the hypothesis that liberation of upper airways and the ventilator’s integration with lung protective reflexes would be equally lung protective.

Methods

In this controlled and randomized in vivo laboratory study, 25 adult White New Zealand rabbits were studied, including five non-ventilated control animals. The twenty animals with aspiration-induced lung injury were randomized to ventilation with either VC (6 mL/kg, PEEP 5 cm H2O, and paralysis) or NIV-NAVA for six hours (PEEP = zero because of leaks). Markers of lung function, lung injury, vital signs and ventilator parameters were assessed.

Results

At the end of six hours of ventilation (n = 20), there were no significant differences between VC and NIV-NAVA for vital signs, PaO2/FiO2 ratio, lung wet-to-dry ratio and broncho-alveolar Interleukin 8 (Il-8). Plasma IL-8 was higher in VC (P <0.05). Lung injury score was lower for NIV-NAVA (P = 0.03). Dynamic lung compliance recovered after six hours in NIV-NAVA but not in VC (P <0.05). During VC, peak pressures increased from 9.2 ± 2.4 cm H2O (hour 1) to 12.3 ± 12.3 cm H2O (hour 6) (P <0.05). During NIV-NAVA, the tracheal end-expiratory pressure was similar to the end-expiratory pressure during VC. Two animals regurgitated during NIV-NAVA, without clinical consequences, and survived the protocol.

Conclusions

In experimental acute lung injury, NIV-NAVA is as lung-protective as VC 6 ml/kg with PEEP.

Electronic supplementary material

The online version of this article (doi:10.1186/cc13706) contains supplementary material, which is available to authorized users.     

CONCURRENT VALIDITY OF DIGITAL INCLINOMETER AND UNIVERSAL GONIOMETER IN ASSESSING PASSIVE HIP MOBILITY IN HEALTHY SUBJECTS

Background:

Hip range of motion is an important component in assessing clinical orthopedic conditions of the hip, low back and lower extremities. However it remains unclear as to what constitutes the best tool for clinical measurement. The purpose of this study was to investigate the concurrent validity of passive range of motion (ROM) measurements of hip extension and hip internal and external rotation using a digital inclinometer and goniometer.

Design:

Criterion Standard

Setting:

Clinical research laboratory

Participants:

30 healthy subjects without pain, radicular symptoms or history of surgery in the low back or hip regions.

Main Outcome Measures:

Passive hip range of motion for extension, hip internal rotation and hip external rotation. A digital inclinometer and universal goniometer were utilized as the tools for comparisons between measurements.

Results:

There was a statistically significant difference (p < 0.05) between the goniometer and digital inclinometer in measured hip ROM except for measurements of right hip external rotation (p > 0.05). The mean difference between the goniometer and digital inclinometer in left hip extension, internal rotation and external rotation were 3.5°, 4.5° and 5.0° respectively. The mean difference between the two devices in right hip extension, internal rotation and external rotation were 2.8°, 4.2° and 2.6° respectively. On average, the difference between the goniometer and digital inclinometer in extension was 3.2°, internal rotation was 4.5° and external rotation was 3.8°. The digital inclinometer had greater measurement during EXT and ER. Furthermore, there was no statistically significant difference (p > 0.05) in hip ROM between the left and right side for either goniometric or digital inclinometer measurements.

Conclusions:

This results of this study indicate that a significant difference exists between the two devices in all measurements with exception of right hip extension. The differences were noted to be between 3–5 degrees for all planes measured. These findings suggest that caution should be used if these two devices are to be used interchangeably to quantify passive hip range of motion in either clinical practice or when comparing studies that utilize different instruments.

Level of Evidence:

2b     

Early fluid loading in acute respiratory distress syndrome with septic shock deteriorates lung aeration without impairing arterial oxygenation: a lung ultrasound observational study

Introduction

The study was designed to assess the impact of fluid loading on lung aeration, oxygenation and hemodynamics in patients with septic shock and acute respiratory distress syndrome (ARDS).

Methods

During a 1-year period, a prospective observational study was performed in 32 patients with septic shock and ARDS. Cardiorespiratory parameters were measured using Swan Ganz (n = 29) or PiCCO catheters (n = 3). Lung aeration and regional pulmonary blood flows were measured using bedside transthoracic ultrasound. Measurements were performed before (T0), at the end of volume expansion (T1) and 40 minutes later (T2), consisting of 1-L of saline over 30 minutes during the first 48 h following onset of septic shock and ARDS.

Results

Lung ultrasound score increased by 23% at T2, from 13 at baseline to 16 (P < 0.001). Cardiac index and cardiac filling pressures increased significantly at T1 (P < 0.001) and returned to control values at T2. The increase in lung ultrasound score was statistically correlated with fluid loading-induced increase in cardiac index and was not associated with increase in pulmonary shunt or regional pulmonary blood flow. At T1, PaO₂/FiO₂ significantly increased (P < 0.005) from 144 (123 to 198) to 165 (128 to 226) and returned to control values at T2, whereas lung ultrasound score continued to increase.

Conclusions

Early fluid loading transitorily improves hemodynamics and oxygenation and worsens lung aeration. Aeration changes can be detected at the bedside by transthoracic lung ultrasound, which may serve as a safeguard against excessive fluid loading.     

Interest of low-dose hydrocortisone therapy during brain-dead organ donor resuscitation: the CORTICOME study

Introduction

Circulatory failure during brain death organ donor resuscitation is a problem that compromises recovery of organs. Combined administration of steroid, thyroxine and vasopressin has been proposed to optimize the management of brain deceased donors before recovery of organs. However the single administration of hydrocortisone has not been rigorously evaluated in any trial.

Methods

In this prospective multicenter cluster study, 259 subjects were included. Administration of low-dose steroids composed the steroid group (n = 102).

Results

Although there were more patients in the steroid group who received norepinephrine before brain death (80% vs. 66%: P = 0.03), mean dose of vasopressor administered after brain death was significantly lower than in the control group (1.18 ± 0.92 mg/H vs. 1.49 ± 1.29 mg/H: P = 0.03), duration of vasopressor support use was shorter (874 min vs. 1160 min: P < 0.0001) and norepinephrine weaning before aortic clamping was more frequent (33.8% vs. 9.5%: P < 0.0001). Using a survival approach, probability of norepinephrine weaning was significantly different between the two groups (P < 0.0001) with a probability of weaning 4.67 times higher in the steroid group than in the control group (95% CI: 2.30 – 9.49).

Conclusions

Despite no observed benefits of the steroid administration on primary function recovery of transplanted grafts, administration of glucocorticoids should be a part of the resuscitation management of deceased donors with hemodynamic instability.