Accuracy of Pocket-sized Ultrasound Devices to Evaluate Inferior Vena Cava Diameter and Variability in Critically Ill Patients.

Purpose: By using inferior vena cava (IVC) measurements, clinicians can detect fluid status and responsiveness and find out the etiology of hypotension, acute heart failure, and sepsis easier. Pocket-sized ultrasound devices (PSUD) may take this advantage a few steps further by their lower costs, user-friendly interface, and easily applicable structure.In this study, we aimed to determine the diagnostic value of a PSUD compared with a standard ultrasound device (SD) for the measurement of IVC diameter (IVCD) and its respiratory variability. Materials and methods: We measured the inspiratory, expiratory diameters of IVC, and calculated the inferior vena cava collapsibility index (IVCCI). We investigated 42 intensive care unit (ICU) patients. Results: There was no difference in inspiratory (PSUD: 1.34 ± 0.67 cm; SD: 1.35 ± 0.68 cm) and expiratory (PSUD: 1.98 ± 0.53 cm; SD: 2.01 ± 0.49 cm) IVCD among measurements with PSUD and SD (p > 0.05). There was also no difference between IVCCI's measured with PSUD (39 ± 20%) and SD (39 ± 20%) (p > 0.05). The Bland-Altman analysis revealed that the width of 95% limits of agreement were similar for both devices. There was a good inter-device agreement among PSUD and SD for measurements of IVCD, and there was no difference between IVCCI's measured using both ultrasound devices. Conclusion: We support that the idea of a PSUD is as reliable as a SD for IVC measurements. How to cite this article: Inci K, Gürsel G. Accuracy of Pocket-sized Ultrasound Devices to Evaluate Inferior Vena Cava Diameter and Variability in Critically Ill Patients. Indian J Crit Care Med 2024;28(4):369-374.

Performance of handheld ultrasound devices in diagnosis of pulmonary hypertension and right heart dysfunction in ICU patients.

AIM: The use of handheld ultrasonography devices (HHUD) has increased recently but there are limited data about their performance in the evaluation of right heart dysfunction (RHD) and pulmonary hypertension (PHT). The aim of the study is to compare the performance of a HHUD with a conventional ultrasound device (CUD) in assessing PHT and RHD. METHODS: This single-center prospective study was performed in a seven-bed teaching hospital intensive care unit (ICU). PHT and RHD criteria were compared by HHUD and CUD. Additional PHT criteria and right ventricle (RV) systolic and diastolic dysfunction criteria were also measured. RESULTS: Forty-six patients were included in the study. There was no significant difference between the imaging rates and mean values of the parameters measured by both devices. When the positivity rates for additional PHT parameters and RHD criteria were compared, there were no significant differences between the devices. In Bland-Altman's analysis, there was good agreement and there was no bias between the measurements of the two devices but left ventricular end-systolic eccentricity index (LVSEI), right atrium area (RAA), and pulmonary artery diameter (PAD). Ninety percent of the patients had PHT probability, of whom 43% had a low, 37% had intermediate and 10% had a high probability of PHT. Ninety-two percent of the patients had RHD and there was no significant difference between the devices in the diagnosis of RHD (p = .212). When RV systolic and diastolic dysfunction evaluations of the devices were compared according to the British Society of Echocardiography (BSE) criteria there was no significant difference between the devices' measurements in the evaluation of systolic and diastolic function. CONCLUSION: The imaging and measurement capabilities of the HHUDs for PHT and RHD parameters were similar to CUDs, and considering the inconsistent parameters, the HHUD can be useful in diagnosing these problems.

Impact of neurological problems on mechanical ventilation and intensive care unit outcomes in pulmonary intensive care unit patients: a retrospective analysis of a single-center cohort.

Neurological problems (NPs) are frequently connected with different critical illnesses in intensive care unit (ICU) patients, and they may influence ICU outcomes. This study aims to examine the effects of NPs on ICU outcomes, especially in pulmonary ICU patients. This is a retrospective observational study comprising adult pulmonary critical care patients who were hospitalized between 2015 and 2019. The frequency of NPs at admission, their impact on mechanical ventilation (MV), ICU outcomes, the rate of NP development during the ICU stay, and risk factors for them were investigated. A total of 361 patients were included in the study, and 130 of them (36%) had NPs (group 1). The noninvasive ventilation requirement rate in patients with NPs was less than in those without NPs (group 2), and the requirement of MV was significantly more frequent in this group (37% and 19%, p<0.05). The duration of MV (19±27 and 8±6 days, p=0.003) and sepsis rate (31% and 18%, p=0.005) were also higher in group 1. NPs developing after ICU admission increased the MV requirement 3 times as an independent risk factor. Risk factors for ICU-acquired NPs were the existence of sepsis during admission [odds ratio (OR): 2.01, confidence interval (CI) 95%: 1.02-4, p=0.045] and longer MV durations before ICU admission (OR: 1.05, CI 95%: 1.004-41.103, p=0.033). NPs were not independent risk factors for mortality (OR: 0.67, CI 95%: 0.37-1.240, p=0.207). NPs did not increase mortality but more frequently caused MV requirement, more extubation failure, and a longer ICU stay in this study population. Additionally, our data suggest that having sepsis during admission and a longer length of MV prior to admission may increase the neurological complication rate.

Risk Factors for Prolonged Intensive Care Unit Stay in Patients with Hypercapnic Respiratory Failure.

INTRODUCTION: Hypercapnic respiratory failure (HRF) is one of the most frequent reasons for intensive care unit (ICU) admissions. In this study, we aimed to investigate the risk factors for prolonged ICU stay in HRF patients for longer than 7, 10, and 15 days. METHODS: Impact of demographics, vitals at the admission, comorbid disease severity, respiratory parameters, admission diagnosis, noninvasive mechanical ventilation (NIV) application time and settings, arterial blood gas, and blood biochemistry results were analyzed in patients with HRF to investigate risk factors for longer ICU stay. RESULTS: A total of 210 patients who were admitted to ICU with HRF (PaCO₂ values of 45 mmHg and higher) were included in this retrospective cohort study. The mean age of the patients was 69 ± 12 years, and the mean ICU duration was 9 ± 7 days. Forty-five percent of the patients stayed in the ICU for more than one week and 10% of them stayed for more than 15 days. Risk factors for a prolonged stay in ICU for more than 7 days were high SOFA score, acute renal failure (ARF) at admission, low PaO₂/FiO₂ on the 2^nd day of admission, and high TSH level. Low FEV1 and FEV1/FVC ratio, ARF at admission, and low PaO₂/FiO₂ ratio on the 2nd day of admission were found to be risk factors for prolonged stay in ICU for longer than 10 days. Significant risk factors prolonging the ICU duration for more than 15 days were high SOFA score, low FEV1, low FEV1/FVC ratio (p = 0.008), and hypothyroidism (p = 0.037). FEV1% predicted less than 25.5% and FEV1/FVC% less than 46.5% were significantly associated with ICU stay longer than 10 days. CONCLUSION: Earlier diagnosis and treatment of patients with hypothyroidism and severe airflow obstruction could shorten the length of ICU stay of hypercapnic patients.

Value of Rox Index to Predict Intubation and Intensive Care Unit Outcome in Patients with Respiratory Failure.

BACKGROUND: Recent literature suggests that the respiratory rate oxygenation (ROX) index may be a useful parameter in predicting intubation indication in hypoxemic patients. OBJECTIVE: In this study, we evaluated the accuracy of the ROX index in predicting intubation, length of stay in the ICU, and mortality in ICU patients with hypoxemic respiratory failure with and without hypercapnia. METHODS: Single-centre retrospective cohort study of 290 patients, with a preliminary diagnosis of respiratory failure, who were treated with low flow oxygen systems. Demographics, medical history, clinical, laboratory, treatment, and prognostic data were obtained from the electronic records of the hospital. The ROX index was calculated at the time of ICU admission. RESULTS: Thirty-seven percent of non-hypercapnic and 69% of hypercapnic patients were intubated (p:0.005). In hypercapnic patients, ROX: 6.9 had highest sensitivity (81%) and specificity (65%) values for intubation (p:0.005). In non-hypercapnic patients, ROX: 6.2 had the highest sensitivity (81%) and specificity (40%) values. While 11% of hypercapnic patients and 30% of non-hypercapnic patients were died (p:0.05), 22% of hypercapnic patients and 33% of non-hypercapnic patients stayed in the ICU longer than 14 days (p:0.044). The highest sensitivity and specificity values were found for mortality in hypercapnic patients; for ROX value of 5.94 (sensitivity:86%, specificity:61%) and for ICU stay longer than 14 days; for ROX value of 7.4 (sensitivity:71%, specificity:68%). CONCLUSION: Results of our study suggest that ROX index calculated during ICU admission can be helpful in predicting intubation indication and length of ICU stay in patients with respiratory failure and hypercapnia may influence the cutoff values.

Assessment of different computing methods of inspiratory transpulmonary pressure in patients with multiple mechanical problems.

While plateau airway pressure alone is an unreliable estimate of lung overdistension inspiratory transpulmonary pressure (PL) is an important parameter to reflect it in patients with ARDS and there is no concensus about which computation method should be used to calculate it. Recent studies suggest that different formulas may lead to different tidal volume and PEEP settings. The aim of this study is to compare 3 different inspiratory PL measurement method; direct measurement (PLD), elastance derived (PLE) and release derived (PLR) methods in patients with multiple mechanical abnormalities. 34 patients were included in this prospective observational study. Measurements were obtained during volume controlled mechanical ventilation in sedated and paralyzed patients. During the study day airway and eosephageal pressures, flow, tidal volume were measured and elastance, inspiratory PLE, PLD and PLR were calculated. Mean age of the patients was 67 ± 15 years and APACHE II score was 27 ± 7. Most frequent diagnosis of the patients were pneumonia (71%), COPD exacerbation(56%), pleural effusion (55%) and heart failure(50%). Mean plateau pressure of the patients was 22 ± 5 cmH2O and mean respiratory system elastance was 36.7 ± 13 cmH2O/L. EL/ERS% was 0.75 ± 0.35%. Mean expiratory transpulmonary pressure was 0.54 ± 7.7 cmH2O (min: - 21, max: 12). Mean PLE (18 ± 9 H2O) was significantly higher than PLD (13 ± 9 cmH2O) and PLR methods (11 ± 9 cmH2O). There was a good aggreement and there was no bias between the measurements in Bland-Altman analysis. The estimated bias was similar between the PLD and PLE (- 3.12 ± 11 cmH2O) and PLE and PLR (3.9 ± 10.9 cmH2O) measurements. Our results suggest that standardization of calculation method of inspiratory PL is necessary before using it routinely to estimate alveolar overdistension.

Are pocket sized ultrasound devices sufficient in the evaluation of lung ultrasound patterns and aeration scoring in pulmonary ICU patients?

Lung ultrasound (LUS) is a practical diagnostic tool for several lung pathologies. Pocket sized USG devices (PSUDs) are more affordable, accessible, practical, and learning to use them is easier than standard ultrasound devices (SUDs). Their capability in image quality have been found as comparable with standard USG machines. Studies have been showing that these devices can be useful as much as SUDs in the evaluation of heart, abdomen, vascular structures, diaphragm and optic nerve. The aim of this study is to compare PSUD with a standard ultrasound devices (SUD) in the evaluation of LUS patterns such as alveolar, interstitial syndromes and lung aeration score (LAS). Study performed in an University Hospital Pulmonary ICU. All patients older than 18 years old were included in this study. The sector probe of SUD (Vivid-Q) and PSUD (Vscan) were used for investigation of A lines, interstitial (B lines), alveolar syndromes (consolidation, hepatisation, air bronchograms) and pleural effusion. 33 patients were included in the study. When PSUD was compared with SUD in terms of total B2 count, and LAS in the right, left and both lung, there was an agreement without proportional bias according to Bland Altman test. There was also good inter class correlation coefficient value as greater than 0.8 and 0.7 between two physicians in terms of counting of total B1, B2, total B lines and calculating of total LAS for SUD and PSUD respectively. PSUDs is a reliable and valid method for evaluation of LUS patterns like SUDs.

The usefulness of subxiphoid view in the evaluation of acceleration time and pulmonary hypertension in ICU patients.

BACKGROUND: Pulmonary hypertension (PHT) is very frequent in ICUs. Estimation of systolic pulmonary artery pressure (PASP) by using tricuspid regurgitation velocity (TRV) is impossible in 25% of patients. However, it may be possible to estimate PHT in these patients by obtaining subxiphoid imaging of short axis (SX-SAX) and measuring pulmonary artery diameter (PAD) and right ventricular outflow tract (RVOT) acceleration time (AT). We first aimed to compare the values of AT and PAD measured at the parasternal short axis view (PSAX) and SX-SAX and then to compare AT measurements obtained in the RVOT and pulmonary artery (PA) in ICU patients. METHODS: This prospective observational study was conducted in a 7-bed ICU of a tertiary academic teaching hospital. Measurements of TRV, PAD, and AT in parasternal and subxiphoid SAX were obtained. AT was measured in RVOT and PA locations. We measured other echocardiographic signs of PHT to assess the probability of PHT in addition to TRV measurements. RESULTS: The study consisted of 61 patients. TRV was measured in 85% of the patients, and SX-SAX was visualized in 78%. The probability of PHT was high (49%) in this study population. There were agreement and no proportional bias between the measurements of PAD and AT at both SX-SAX and PSAX. Measurements of AT in the RVOT and PA were similar, as well. CONCLUSION: These results suggested that measurements of AT in the PSAX and SX-SAX and RVOT and PA were similar in the ICU patients.

Validity and reliability of pocket-sized ultrasound devices in measurement of optic nerve sheath diameter in ICU patients.

The measurement of the optic nerve sheath diameter (ONSD) by ultrasonography (USG) is particularly important for intracranial pressure (ICP) monitoring when invasive measurements are not possible or are contraindicated. Standard USG (SUDs) devices can be bulky and may break down the workflow. The validity and reliability of pocket-sized USG devices (PSUDs) compared to SUDs for ONSD measurement has not been investigated, yet. We compared the reliability and validity of PSUDs with SUDs for ONSD measurement. 35 patients were included in the study. ONSD measurements with PSUDs and SUDs were performed by two clinicians as three different measurements in both sagittal and transverse axis of the eye. There was agreement between mean transverse ONSD (mtONSD), mean sagittal ONSD (msONSD), and mean ONSD(mONSD) values measured with each device according to Bland-Altman test (p = 0.166, p = 0.135, p = 0.066, respectively) with no proportional bias (p = 0.544, p = 0.868, p = 0.929, respectively). Intraclass correlation coefficients (ICC) were found to be greater than 0.7 for mtONSD, msONSD, and mONSD values measured by SUD (ICC = 0.790, ICC = 0.817, and ICC = 0.844, respectively). Similarly, for mtONSD, msONSD, and mONSD values measured by PSUD, ICC were found greater than 0.7 (ICC = 0.763, ICC = 0.814, and ICC = 0.843, respectively). There was no statistically significant difference between mtONSD and msONSD (p = 0.441 for SUD and p = 0.893 for PSUD). There was a good correlation between mtONSD and msONSD (r = 0.767 for SUD and r = 0.816 for PSUD). The total variance between three different measurements in the transverse and sagittal axis was ± 0.6 mm. PSUDs can be used with similar validity and reliability as SUDs for ONSD measurement.

Does it make difference to measure diaphragm function with M mode (MM) or B mode (BM)?

Diaphragm dysfunction occurs in mechanically ventilated subjects. Recent literature suggests that diaphragm thickening fraction (DTF) measured by ultrasound can be useful to predict weaning outcome. However, there is no standardized approach in the measurement of diaphragm thickness (DT) and limited data exists comparing different measurement techniques of diaphragm thickness (M mode-MM or B mode-BM). The goal of this study was to compare MM with BM in the measurements of DT and excursion in the ICU subjects. DT measurements were obtained from the right diaphragm during tidal and maximal inspiratory breathing. Three measurements of the DT were taken both in MM and BM and their mean values were calculated. DT was measured during inspiration and expiration and DTF was calculated. Excursion of diaphragm was also measured with MM and BM during tidal and maximal inspiratory breathing. Bias and agreement between the two measurement methods were evaluated with Bland and Altman test. Sixty-two subjects were enrolled in the study. While 25 (40%) subjects were receiving invasive mechanical ventilation, 14 (23%) subjects ventilated noninvasively. There were no significant difference between the measurement results of MM and BM. BM and MM tidal diaphragm measurements during the inspiratory (0.3 ± 0.08 and 0.31 ± 0.08 cm; P = 0.022), expiratory (0.24 ± 0.07 and 0.24 ± 0.07 cm; P = 0.315) phases and tidal DTF were (27 ± 16 and 31 ± 14%, P = 0.089) respectively. Results of our study suggests that except tidal inspiratory diaphragm thickness, all thickness and excursion measurements with MM and BM are very compatible with each other. Further studies are necessarry to confirm our results and to standardize the measurements of diaphragm.

Can Diaphragm Dysfunction Be Reliably Evaluated with Pocket-Sized Ultrasound Devices in Intensive Care Unit?

BACKGROUND: Diaphragm dysfunction (DD) is frequently seen in critically ill patients, and ultrasound could be a useful tool to detect it and to predict extubation success or failure in mechanically ventilated patients. Besides, it would also be useful in differential diagnosis of dyspnea and respiratory failure. The aim of this study is to evaluate usefulness and accuracy of pocket-sized ultrasound devices (PSDs) in assessment of DD in intensive care unit (ICU) patients in comparison with standard ultrasound devices (SD). METHODS: In this prospective observational study, we compared the performance of PSD and SD in visualization of diaphragm, detection of paradoxical movement, measurement of tidal and maximal thickness, tidal and maximal excursion, and calculation of thickening fraction (TF) of the diaphragm. We used Bland and Altman test for agreement and bias analysis and intraclass correlation analysis to evaluate interobserver variability. RESULTS: Thirty-nine patients were included in the study. In 93% of the patients, diaphragm was visualized with PSD. There was very good agreement between the measurements of the devices, and there was no proportional bias in the measurements of tidal inspiratory and expiratory thickness, tidal TF, tidal excursion, and maximal inspiratory thickness. In interobserver reliability analysis of all measurements for both devices, ICC coefficients were higher than 0.8. Total diaphragm examination times of the devices were similar (p > 0.05). CONCLUSION: These results suggest that PSD can be useful in ICU patients for evaluating DD. But further studies are required to determine the exact place of these devices in evaluation of DD in ICU patients.

Pulmonary artery leiomyosarcoma: A clinical dilemma.

Leiomyosarcomas are rare neoplasms of the smooth muscles. Primary pulmonary leiomyosarcomas, which constitute approximately 0.2%-0.5% of all primary lung malignancies, are extremely rare and highly lethal. They may originate from the smooth muscle cells of the bronchial wall, the blood vessels, or the pulmonary interstitium, and their rare occurrence, localization, and nonspecific clinical symptoms mean that correct diagnosis and proper management are often delayed. Here, we report a rapidly growing primary pulmonary leiomyosarcoma, which invaded the right atrium, vena cava superior, mediastinum, right hilar area, and left pulmonary artery within 4 months. On histopathology, a transthoracic needle biopsy of the mass confirmed leiomyosarcoma, and delayed presentation meant that there was a local spread to the neighboring structures at the time of diagnosis.

Noninvasive auto-titrating ventilation (AVAPS-AE) versus average volume-assured pressure support (AVAPS) ventilation in hypercapnic respiratory failure patients.

Auto-titrating noninvasive ventilation (NIV) has been developed as a new mode applying variable expiratory-positive airway pressure (EPAP) in addition to variable inspiratory pressures (IPAP), both to deliver targeted tidal volume (VT) and to eliminate upper airway resistance. The purpose of this study is to evaluate whether NIV with auto-titrating mode will decrease more PaCO2 within a shorter time compared to volume-assured mode in hypercapnic intensive care unit (ICU) patients. The hypercapnic respiratory failure patients treated with average volume assured pressure support- automated EPAP mode (group1) were compared with those treated with average volume-assured pressure support mode (group2). Two groups were matched with each other according to baseline diagnoses, demographic characteristics, arterial blood gas values, target VT settings and daily NIV usage times. Built-in software was used to gather the ventilatory parameters. Twenty-eight patients were included in group 1, and 22 in group 2. The decrease in PaCO2 had been achieved within a shorter time period in group 1 (p < 0.05). This response was more pronounced within the first 6 h (mean reduction in PaCO2 was 7 ± 7 mmHg in group 1 and 2 ± 5 mmHg in group 2, p = 0.025), and significantly greater reductions in PaCO2 (18 ± 11 mmHg in group 1 and 9 ± 8 mmHg in group 2, p = 0.008) and plasma HCO3 levels (from 32 to 30 mEq and from 35 to 35 mEq, p = 0.007) took place within first 4 days. While mean IPAP was similar in both groups, maximum EPAP, mean VT and leak were significantly higher in group 1 than in group 2 (p < 0.05). Results of this preliminary study suggest that, this new auto-titrating NIV mode may provide additional benefit on volume-assured mode in decreasing PaCO2 more efficiently and rapidly in hypercapnic ICU patients.

Effects of Modes, Obesity, and Body Position on Non-invasive Positive Pressure Ventilation Success in the Intensive Care Unit: A Randomized Controlled Study.

OBJECTIVES: Different outcomes and success rates of non-invasive positive pressure ventilation (NPPV) in patients with acute hypercapnic respiratory failure (AHRF) still pose a significant problem in intensive care units. Previous studies investigating different modes, body positioning, and obesity-associated hypoventilation in patients with chronic respiratory failure showed that these factors may affect ventilator mechanics to achieve a better minute ventilation. This study tried to compare pressure support (BiPAP-S) and average volume targeted pressure support (AVAPS-S) modes in patients with acute or acute-on-chronic hypercapnic respiratory failure. In addition, short-term effects of body position and obesity within both modes were analyzed. MATERIAL AND METHODS: We conducted a randomized controlled study in a 7-bed intensive care unit. The course of blood gas analysis and differences in ventilation variables were compared between BiPAP-S (n=33) and AVAPS-S (n=29), and between semi-recumbent and lateral positions in both modes. RESULTS: No difference was found in the length of hospital stay and the course of PaCO2, pH, and HCO3 levels between the modes. There was a mean reduction of 5.7±4.1 mmHg in the PaCO2 levels in the AVAPS-S mode, and 2.7±2.3 mmHg in the BiPAP-S mode per session (p<0.05). Obesity didn't have any effect on the course of PaCO2 in both the modes. Body positioning had no notable effect in both modes. CONCLUSION: Although the decrease in the PaCO2 levels in the AVAPS-S mode per session was remarkably high, the course was similar in both modes. Furthermore, obesity and body positioning had no prominent effect on the PaCO2 response and ventilator mechanics. Post hoc power analysis showed that the sample size was not adequate to detect a significant difference between the modes.

Evaluation of nephrotoxicity and prognosis in patients treated with colistin due to hospital-acquired pneumonia.

INTRODUCTION: Colistimethate sodium (CMS) is frequently used in the treatment of nosocomial multidrug-resistant gram-negative infections. Nephrotoxicity is the most important side effect. The aim of this study is to evaluate the effect of colistin on nephrotoxicity and to assess prognosis in patients treated with CMS due to hospital-acquired pneumonia (HAP). MATERIALS AND METHODS: Patients treated with CMS for HAP due to multidrug-resistant Pseudomonas aeruginosa or Acinetobacter baumannii were included in this cohort study. RESULT: We evaluated 281 patients treated with two different brands of CMS whose administration dose is different: imported (n= 58, low dose/kg) and domestic (n= 223, high dose/kg). Nephrotoxicity developed in 175 patients (62.3%). The median age (73 vs. 66 years, p= 0.004) and mortality rates were higher (66.9% vs. 52.8%, p= 0.022) in patients having nephrotoxicity. The patients receiving high dose/kg had higher nephrotoxicity rate (67.7% vs. 41.4%, p< 0.001). The clinical, bacteriological response and mortality rates of the whole group were 52.0%, 61.0%, 61.6%, respectively. The clinical and bacteriological response rates were similar in the different dose groups. Multivariate analysis showed that nephrotoxicity was associated with domestic brand depending on use of high dose (OR= 3.97), advanced age (ß= 0.29, p= 0.008), male gender (OR= 2.60), hypertension (OR= 2.50), red blood cells transfusion (OR= 2.54), absence of acute kidney injury (OR= 10.19), risk stage of RIFLE (OR= 11.9). CONCLUSIONS: Nephrotoxicity is associated with the use of high dose colistin, age, gender, hypertension, red blood cells replacement and RIFLE stage. The mortality rate is higher in patients developing nephrotoxicity.

A promising marker in early diagnosis of septic acute kidney injury of critically ill patients: urine insulin like growth factor binding protein-7.

AIM: An ideal biomarker for early diagnosis of septic acute kidney injury (AKI) should reflect renal stress or damage at initiation point, at cellular level. The aim of this study was to assess the role of a urinary cell cycle arrest marker, insulin-like growth factor-binding protein 7 (IGFBP7) in early diagnosis of septic AKI in adult critical care patients. METHODS: This was a single-center prospective cohort study. Patients without AKI, admitted to a medical intensive care unit (ICU) between January 2010 and March 2013, were included. According to 'sepsis' and 'AKI' development during their ICU stay, they were grouped as 'sepsis-non AKI', 'sepsis-AKI' and 'non-sepsis-non AKI (control)'. Among these groups, urine IGFBP7 was studied and compared with Human ELISA Kit/96 Test/USCNK(®) first on admission and then on daily collected serial urine samples. RESULTS: A total of 118 patients formed the cohort; 52 in sepsis-non AKI, 43 in sepsis-AKI, 23 in control group. Admission urine IGFBP7 predicted septic AKI development with 72% sensitivity and 70% specificity for a threshold level of 2.5 ng/mL with an area under the receiver operating characteristics curve (AUC) of 0.79 (95% CI: 0.70-0.88). No impact of sepsis was observed on urine IGFBP7 levels in the absence of AKI. In the septic AKI group urine IGFBP7 levels continuously increased up to the day of AKI development and high levels were suspended for 10 days further. CONCLUSION: Admission urine IGFBP7 levels and following its course in ICUs can be used as a promising new biomarker for the early diagnosis of septic AKI development without being affected by sepsis itself.