Correlation of Inferior Vena Cava diameter and IVC Collapsibility Index with Central Venous Pressure (CVP) in critically ill surgical patients

Introduction: Central Venous Pressure is a valuable parameter in the management of critically ill surgical patients in the ICU. Non-invasive methods to extrapolate the volume status of the patient can aid clinicians in expediting proper treatment. The objective of this study is to find a correlation between Inferior Vena cava (IVC) diameter and collapsibility index (CI) with Central venous pressure (CVP) in critically ill surgical patients. Methods: This cross-sectional study included 60 critically ill patients from September 2020 – 31st February 2021. We recorded the patient's age, sex, heart rate, blood pressure, CVP, volume status, IVC minimum, and maximum diameter. After taking consent and explaining the procedure to the patient, the maximum IVC anteroposterior diameter was noted at the end of inspiration and end of expiration in centimeters. IVC collapsibility index was calculated using the formula ([IVCdmax-IVCdmin]/IVCdmax*100%). Following this, the CVP of the patient was measured. Results: Among the patients evaluated, 32 were females. The mean age of the participants was 44.90 ± 15.76 years. The mean central venous pressure maintained was 11.10 ± 2.11cm H2O with an inferior vena cava collapsibility index of 29.69 ± 8.75. There was a negative correlation between CVP and IVC collapsibility index (%), which was statistically significant (r = -0.701, n = 60, p < 0.01). A strong positive correlation between CVP and maximum IVC diameter (r = 0.712, n = 60, p < 0.01) and minimum IVC diameter (r = 0.796, n = 60, p < 0.01) was found. Conclusion: Inferior Vena Cava diameter and IVC Collapsibility Index can be used as a reliable substitute to central venous pressure to determine the patient's volume status.

The association between culture positivity and long-term mortality in critically ill surgical patients

Background The long-term outcome is an essential issue in critically ill patients, and the identification of early determinant is needed for risk stratification of the long-term outcome. In the present study, we investigate the association between culture positivity during admission and long-term outcome in critically ill surgical patients. Methods We linked the 2015–2019 critical care database at Taichung Veterans General Hospital with the nationwide death registration files in Taiwan. We described the long-term mortality and proportion of culture positivity among enrolled subjects. We used a log-rank test to estimate survival curves between patients with and without positive cultures and a multivariable Cox proportional hazards regression model to determine hazard ratio (HR) and 95% confidence interval (CI). Results A total of 6748 critically ill patients were enrolled, and 32.5% (2196/6749) of them died during the follow-up period, with the overall follow-up duration was 1.8 ± 1.4 years. We found that 31.4% (2122/6748) of critically ill patients had at least one positive culture during the index admission, and the number of patients with positive culture in the blood, respiratory tract, urinary tract, skin and soft tissue and abdomen were 417, 1702, 554, 194 and 139, respectively. We found that a positive culture from any sites was independently associated with high long-term mortality (aHR 1.579, 95% CI 1.422–1.754) after adjusting relevant covariates, including age, sex, body-mass index, comorbidities, severity score, shock, early fluid overload, receiving mechanical ventilation and the need of renal replacement therapy for critical illness. Conclusions We linked two databases to identify that a positive culture during admission was independently correlated with increased long-term mortality in critically ill surgical patients. Our findings highlight the need for vigilance among patients with a positive culture during admission, and more studies are warranted to validate our findings and to clarify underlying mechanisms.

Impact of Early Fluid Balance on Long-Term Mortality in Critically Ill Surgical Patients: A Retrospective Cohort Study in Central Taiwan

Fluid balance is an essential issue in critical care; however, the impact of early fluid balance on the long-term mortality in critically ill surgical patients remains unknown. This study aimed to address the impact of day 1–3 and day 4–7 fluid balance on the long-term mortality in critically ill surgical patients. We enrolled patients who were admitted to surgical intensive care units (ICUs) during 2015–2019 at a tertiary hospital in central Taiwan and retrieved date-of-death from the Taiwanese nationwide death registration profile. We used a Log-rank test and a multivariable Cox proportional hazards regression model to determine the independent mortality impact of early fluid balance. A total of 6978 patients were included for analyses (mean age: 60.9 ± 15.9 years; 63.9% of them were men). In-hospital mortality, 90-day mortality, 1-year and overall mortality was 10.3%, 15.8%, 23.8% and 31.7%, respectively. In a multivariable Cox proportional hazard regression model adjusted for relevant covariates, we found that positive cumulative day 4–7 fluid balance was independently associated with long-term mortality (aHR 1.083, 95% CI 1.062–1.105), and a similar trend was found on day 1–3 fluid balance, although to a lesser extent (aHR 1.027, 95% CI 1.011–1.043). In conclusion, the fluid balance in the first week of ICU stay, particularly day 4–7 fluid balance, may affect the long-term outcome in critically ill surgical patients.

The Combination of SOFA Score and Urinary NGAL May Be an Effective Predictor for Ventilator Dependence among Critically Ill Surgical Patients: A Pilot Study

Background: Ventilator dependence (VD) has been considered as a serious complication in critically ill patients in the intensive care unit (ICU). Acute kidney injury (AKI) is associated with VD as a result of lung–kidney interaction. The aim of our study was to investigate novel biomarkers in predicting ventilator dependence in critically ill surgical patients. Methods: Patients who were admitted to surgical ICU were enrolled and their serum and urine samples were collected. Novel biomarkers including gelatinase-associated lipocalin (NGAL), calprotectin, kidney injury molecule-1 (KIM-1), cystatin C, and growth differentiation factor 15 (GDF-15) were analyzed and correlated with clinical outcome. Results: A total of 33 patients were enrolled and analyzed. The majority of them received abdominal surgery prior to ICU admission. Thirteen patients were classified into the VD group, while the remaining 20 were in a non-ventilator dependence group (nVD). Statistical analysis demonstrated that the following were significantly higher in the VD group than in the nVD group: serum NGAL (420.25 ± 45.18 ng/mL vs. 314.68 ± 38.12 ng/mL, p-value 0.036), urinary NGAL (420.87 ± 41.08 ng/mL vs. 250.84 ± 39.45 ng/mL, p-value 0.002), SOFA score (11.3 ± 1.5 vs. 5.6 ± 0.7, p-value 0.001), and APACHE II score (23.2 ± 2.6 vs. 13.6 ± 0.8, p-value 0.001). The area under the ROC curve (AUROC) of urinary NGAL for VD was 0.808. The combination of urinary NGAL and SOFA score could further increase AUROC for VD to 0.835. Conclusions: The current study demonstrated the predictive capability of urinary NGAL for ventilator dependence among critically ill surgical patients. When combined with SOFA score, the predictive ability was further augmented. Further large-scale studies are warranted to validate our findings.

Liver function, quantified by the LiMAx test, as a predictor for the clinical outcome of critically ill patients treated with linezolid

BACKGROUND: Critically ill patients commonly suffer from infections that require antimicrobial therapy. In previous studies, liver dysfunction was shown to have an essential impact on the dose selection in these patients. This pilot study aims to assess the influence of liver dysfunction, measured by the novel LiMAx test, on clinical outcomes in critically ill patients treated with linezolid. METHODS: Twenty-nine critically ill patients were included and treated with linezolid. Indications for linezolid therapy were secondary or tertiary peritonitis (46.7%), bloodstream infection (6.7%) and 46.7% were other infections with gram-positive bacteria. Linezolid Cmin, maximal liver function capacity (LiMAx test) and plasma samples were collected while linezolid therapy was in a steady-state condition. Furthermore, potential factors for the clinical outcome were investigated using logistic regression analysis. Clinical cure was defined as the resolution or significant improvement of clinical symptoms without using additional antibiotic therapy or intervention. RESULTS: Cured patients presented lower median linezolid Cmin yet a significantly higher mean LiMAx-value compared to the clinical failure group (1.9 mg/L vs. 5.1 mg/L) (349 μg/kg/h vs. 131 μg/kg/h). In the logistic regression model, LiMAx < 178 μg/kg/h was the only independent predictor of clinical failure with a sensitivity of 77% and specificity of 93%. CONCLUSIONS: The LiMAx test predicts clinical failure more precisely than linezolid trough levels in critically ill surgical patients. Therefore liver failure may have a stronger impact on the outcome of critically ill surgical patients than low linezolid Cmin. While linezolid Cmin failed to predict patient’s outcome, LiMAx results were the only independent predictor of clinical failure.