Retrospective analysis of inferior vena cava collapsibility with point of care ultrasound and urine sodium and FENa in patients with early stage acute kidney injury

Follow-up of perfusion index and inferior vena cava collapsibility index in fluid therapy in prerenal acute renal failure

Introduction

Acute renal failure (ARF), which may occur as a result of hypovolemia, is frequently diagnosed in emergency departments. It is essential to determine these patients' volume status and fluid requirement. The aim of this study was to examine the change in the inferior vena cava (IVC) collapsibility index and perfusion index (PI) in order to evaluate fluid deficit, volume status, and response to fluid therapy in patients with prerenal ARF who presented with signs of hypovolemia.

Materials and methods

The study sample included 104 patients diagnosed with prerenal ARF due to hypovolemia in our emergency department. After obtaining informed consent from the patients, intravenous (IV) fluid therapy (20 cc/kg IV infusion of 0.9% sodium chloride solution for 30 min) was initiated. The PI and IVC collapsibility index were measured before and after the treatment.

Results

Of the patients included in this study, 56.7% were women. The mean age was 76.06 years. Of the patients, 46.2% had a history of multiple diseases. Avoidant/restrictive food intake disorder was the most common complaint (28.8%). The mean PI of the patients was 2.20 at admission, which increased to 3.27 after treatment. The mean IVC collapsibility index was 38.39 at admission, which decreased to 29.36 after treatment. There was a significant and negative correlation between the PI and IVC collapsibility index of the patients.

Conclusions

Early diagnosis and treatment of ARF in emergency departments are critical. Serial measurements of the IVC collapsibility index and PI are helpful in monitoring patients' response to fluid therapy.

The Value of Inferior Vena Cava Ultrasonography Administration for Hypovolemia Detection in Patients with Acute Kidney Injury Hospitalized in Intensive Care Unit

Background

The hypo-perfusion of the kidneys can lead to impairment in renal function and induce renal injury in case of delayed diagnosis and treatment. To date, laboratory markers are routinely used to determine the fluid volume status of the patients. The current study aims to evaluate the values of inferior vena cava (IVC) collapsibility index in hypovolemia diagnosis among critical patients admitted at the intensive care unit (ICU).

Materials and Methods

This is a cross-sectional study performed on 67 patients admitted to the ICU due to acute kidney injury from May 2018 to October 2019. Hypovolemia was assessed assessing IVC collapsibility using ultrasonography. Laboratory data, including urine osmolality, urine-plasma creatinine ratio, sodium excretion fraction and urinary sodium level were checked. Afterward, IVC collapsibility index was measured for each patient using ultrasonography and the values of this index in accordance with the mentioned criteria was evaluated. Accordingly, reciever operating curve was depicted.

Results

There was no significant asosociation between IVC collapsibility index with fractional excretion of sodium (P = 0.69), urine Na (P = 0.93) and urine osmolality ([P = 0.09]), while urine: Plasma creatinie ration revealed a significant association with IVC collapsibility index at cut point of 40.5% with sensitivity and specificity of 96% and 44% (P = 0.017, area under the curve: 0.67, 95% confidence interval: 0.551-0.804), respectively.

Conclusion

According to the findings of this study, IVC collapsibility detected via ultrasonography was not an appropriate index to figure out hypovolemia in ICU patients. Furthermore, detailed studies are recommended.

Accuracy of Multi-organ Point-of-Care Ultrasound for Acute Kidney Injury Etiologies

This study investigated the diagnostic performance of point-of-care ultrasound (POCUS) for acute kidney injury (AKI) etiological subgroups in emergency department (ED) patients. Multi-organ POCUS including kidney, bladder, inferior vena cava (IVC), lung and cardiac examinations were used to identify five AKI subgroups: hypovolemia, reduced cardiac output, systemic vasodilatation and renal vasomodulation, renal and post-renal. One hundred sixty-five AKI patients were included in the study. The most diagnostic parameter in the post-renal group was the presence of any hydronephrosis, with a sensitivity of 93.3% (95% confidence interval [CI]: 68.1-99.8) and specificity of 85.9% (95% CI: 79.3-91.1). For the reduced cardiac output group, the most diagnostic parameter was IVC maximum diameter >17 mm with a sensitivity of 100% (95% CI: 83.2-100) and specificity of 70.2% (95% CI: 61.6-77.7). For the hypovolemia group, the most diagnostic parameter was IVC maximum diameter ≤17.9 mm with a sensitivity of 81.2% (95% CI: 71.2-88.8) and specificity of 56.5% (95% CI: 44-68.4). For the systemic vasodilatation and renal vasomodulation group, the most diagnostic parameter was diffuse ascites with a sensitivity of 56.3% (95% CI: 29.9-80.2) and specificity of 89.9% (95% CI: 83.8-94.2). None of the parameters were significant for the renal group. We concluded that multi-organ POCUS is of diagnostic value for AKI subgroups.

[Use of pocket-sized ultrasound in internal medicine (hospitalist) practice: Feedback and perspectives]

INTRODUCTION

Point of care ultrasound (POCUS) is routinely used by intensivists and emergency physicians for many years. Its interest is not arguable any more for these specialists, despite the large variety of diseases they care. Hospitalists and internists also should find some interest in POCUS, which convenience and wide range of indications responds well to the variety of their practice. However, it is still not widely used in internal medicine departments.

METHODS

We here report our experience of using a pocket-sized ultrasound device in a French internal medicine department. The device used was a Vscan Dual Probe, GE, whose two probes and presets allow for cardiac, abdominal, pulmonary, obstetric, vascular, pulmonary, and superficial soft tissue exploration. One physician of the ward received a course for POCUS that was initially dedicated for emergency physicians. This study reports on the results of the examinations made between January and September 2015. For each examination performed, clinical usefulness was assessed at the time of patient discharge, by two independent physicians who reviewed the clinical course and the results of conventional imaging and rated their evaluation on a Likert scale.

RESULTS

One hundred and four examinations were evaluated. The mean duration of the ultrasound examination was 9±5minutes. The POCUS conclusions were corrected by disease course or the results of conventional imaging in 10 (9.6%) cases. The presets of the device: heart, soft tissue, lung, abdomen and vascular were used respectively in 32, 30, 21, 12 and 5% of the examinations. The main indications of POCUS examination were for identification of pleural, pericardial or peritoneal effusion, and to assess the central venous pressure by inferior vena cava examination. Eighteen examinations were performed for puncture of effusion. The retrospectively evaluated clinical benefit was clearly demonstrated in 78% of cases. The agreement between the two blinded assessors was good (kappa coefficient at 0.82).

CONCLUSION

Pocket-sized ultrasound device could be used in internal medicine wards. However, its limited performance compared to more sophisticated echography limits the possible explorations and their reliability, which encourages caution and makes critical the question of the initial training of doctors and medical students.