Brain-type natriuretic peptide and right ventricular end-diastolic volume index measurements are imprecise estimates of circulating blood volume in critically ill subjects

Measurement of Blood Volume in Patients with Heart Failure: Clinical Relevance, Surrogates, Historical Background and Contemporary Methodology

The development of clinical congestion resulting from volume overload, either by renal fluid retention or redistribution of blood volume from venous reservoirs, is a recurrent scenario in patients with chronic heart failure (HF). As a result, the treatment of congestion, most commonly by initiating aggressive diuretic therapy, is a front-line issue in the management of patients with HF. However, the association of clinical congestion and volume overload with physical signs and symptoms, as well as other surrogates of volume assessment, has limitations in accuracy and, therefore, reliability to direct appropriate interventions. The ability to quantitate intravascular volume and identify the variability in volume profiles among patients with HF can uniquely inform individualized volume management and aid in risk stratification. This tool is provided by contemporary nuclear medicine-based BVA-100 methodology, which uses the well-established indicator-dilution principle and is a requested topic for discussion in this review.

Brain natriuretic peptide and cardiac troponin I for prediction of the prognosis in cancer patients with sepsis

BACKGROUND

This article aimed to study the value of brain natriuretic peptide (BNP) and cardiac troponin I(cTnI) for predicting the prognosis in cancer patients with sepsis.

METHODS

A cohort of 233 cancer patients with sepsis admitted to our ICU from January 2017 to October 2020 was included in this retrospective study. The data of BNP and cTnI on the first day (d1) and the third day(d3) after entering ICU, blood lactate (Lac), procalcitonin (PCT), Leucocyte and Sequential Organ failure assessment (SOFA) scores within 24 hr of entering ICU, the incidence of septic shock, acute kidney injury(AKI), acute respiratory failure (ARF) or sepsis-induced myocardial dysfunction(SIMD) in ICU, fluid balance in 24 hr and 72 hr after entering ICU, time of mechanical ventilation(MV), length of stay, emergency surgery were collected. According to 28-day mortality, patients were divided into survival group (190 cases) and death group (43 cases). All the above variables were compared.

RESULTS

BNP was an independent predictor for the mortality in these patients (P < 0.05).While cTnI was not. BNP on d3 in 681.5 pg/ml predicted the mortality with a sensitivity of 91.5 % and a specificity of 88.7 %. All patients were divided into the new two groups following the cutoff value of BNP on d3(681.5pg/ml), and the survival curve showed a significant difference with Kaplan-Meier analysis (P < 0.05). BNP had statistical differences between four groups based on the comorbidities(septic shock, AKI, ARF or SIMD), but cTnI was not.

CONCLUSIONS

BNP was a great predictor for the prognosis of cancer patients with sepsis, while cTnI was not.

Refractory Hypertension in Infantile-Onset Denys-Drash Syndrome

Denys-Drash syndrome is characterized by progressive nephropathy, gonadal dysgenesis, and Wilms tumor caused by a WT1 gene mutation. Infants with Denys-Drash syndrome frequently experience severe hypertension, but detailed clinical manifestations have yet to be clarified. Cases of infantile-onset Denys-Drash syndrome with severe hypertension at our hospital were retrospectively analyzed and the pathogenesis of hypertension was investigated. Six infants who received the diagnosis of Denys-Drash syndrome at the median age of 10 days (range: 2-182 days) were enrolled. Five infants had the complication of severe hypertension within a few days of diagnosis. All the patients showed rapid progression to end-stage renal disease and urgently required dialysis due to anuria/oliguria and hypervolemia with a median duration of 7.5 days (range: 0-17 days) on the day after diagnosis. Even under dialysis, all the patients continued to need antihypertensive treatment. Five patients underwent a preventive nephrectomy for Wilms tumor, and one patient underwent a nephrectomy due to progression to Wilms tumor. Two patients developed hypotension after a nephrectomy. The main causes of hypertension were hypervolemia in the predialysis stage, renin-associated hypertension in the dialysis stage, and multiple factors, including increased plasma catecholamine-associated hypertension in the postnephrectomy dialysis stage. At last the follow-up after bilateral nephrectomy, four of the five patients required antihypertensive treatment. Not all the patients showed target organ complications caused by hypertension. Severe hypertension is a common complication of infantile-onset Denys-Drash syndrome. The possibility of hypotension after nephrectomy should be considered in patients with Denys-Drash syndrome.

The role of natriuretic peptides in the management, outcomes and prognosis of sepsis and septic shock

Sepsis continues to be a leading public health burden in the United States and worldwide. With the increasing use of advanced laboratory technology, there is a renewed interest in the use of biomarkers in sepsis to aid in more precise and targeted decision-making. Natriuretic peptides have been increasingly recognized to play a role outside of heart failure. They are commonly elevated among critically ill patients in the setting of cardiopulmonary dysfunction and may play a role in identifying patients with sepsis and septic shock. There are limited data on the role of these biomarkers in the diagnosis, management, outcomes and prognosis of septic patients. This review seeks to describe the role of natriuretic peptides in fluid resuscitation, diagnosis of ventricular dysfunction and outcomes and the prognosis of patients with sepsis. B-type natriuretic peptide (BNP) and N-terminal pro-BNP (NT-proBNP) have been noted to be associated with left ventricular systolic and diastolic and right ventricular dysfunction in patients with septic cardiomyopathy. BNP/NT-proBNP may predict fluid responsiveness, and trends of these peptides may play a role in fluid resuscitation. Despite suggestions of a correlation with mortality, the role of BNP in mortality outcomes and prognosis during sepsis needs further evaluation.

The utility of brain natriuretic peptides in septic shock as markers for mortality and cardiac dysfunction: A systematic review

OBJECTIVE

To conduct a systematic review evaluating the utility of brain natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP) as biomarkers in adult patients with septic shock.

MATERIALS AND METHODS

Pubmed/Medline databases were searched from inception to November 2018 using the search terms: (septic[Title/Abstract] AND shock[Title/Abstract]) AND bnp[Title/Abstract]) and (septic[Title/Abstract]) AND shock[Title/Abstract]) AND natriuretic[Title/Abstract]). No restriction was applied regarding date of publication. Comparative observational studies evaluating BNP and NT-proBNP in patients with septic shock aged ≥18 years were eligible for inclusion. Bibliographies from the extracted articles were also reviewed to identify additional relevant publications.

RESULTS

In total, 46 studies met all eligibility criteria and were included. A strong body of literature has demonstrated that in patients with septic shock, increased values of BNP and NT-proBNP are associated with increased mortality. An increase from baseline BNP values has also been associated with increased mortality, whereas decreases from baseline values are not related to worse outcome. Brain natriuretic peptides have also been associated with cardiac dysfunction in patients with sepsis. Moreover, BNP values have been found to be significantly elevated in septic shock, regardless of cardiac dysfunction, and have been used to distinguish between septic and cardiogenic shock. Furthermore, BNP and NT-proBNP are significantly increased in patients with septic shock, compared to patients with sepsis and severe sepsis.

CONCLUSIONS

BNP and NT-proBNP appear to be reliable predictors of outcome in septic shock.

Blood volume analysis as a guide for dry weight determination in chronic hemodialysis patients: a crossover study

BACKGROUND

Volume overload and depletion both lead to high morbidity and mortality. Achieving euvolemia is a challenge in patients with end stage kidney disease on hemodialysis (HD). Blood volume analysis (BVA) uses radiolabeled albumin to determine intravascular blood volume (BV). The measured BV is compared to an ideal BV (validated in healthy controls). We hypothesized that BVA could be used in HD to evaluate the adequacy of the current clinically prescribed "estimated dry weight" (EDW) and to titrate EDW in order to improve overall volume status. We were also interested in the reproducibility of BVA results in end stage kidney disease.

METHODS

Twelve adults on chronic HD were recruited; 10 completed the study. BVA (Daxor, New York, NY, USA) was used to measure BV at baseline. EDW was kept the same if the patient was deemed to be euvolemic by BVA otherwise, the prescribed EDW was changed with the aim that measured BV would match ideal BV. A second BVA measurement was done 1-3 months later in order to measure BV again.

RESULTS

Based on BVA, 6/10 patients were euvolemic at baseline and 5/10 were euvolemic at the second measurement. When comparing patients who had their prescribed EDW changed after the initial BVA to those who did not, both groups had similar differences between measured and ideal BV (P = 0.75). BV values were unchanged at the second measurement (P = 0.34) and there was no linear correlation between BV change and weight change (r² = 0.08).

CONCLUSIONS

This pilot study is the first longitudinal measurement of BVA in HD patients. It revealed that changing weight did not proportionally change intravascular BV. BV remained stable for 1-3 months. BVA may not be helpful in clinically stable HD patients but studies on patients with hemodynamic instability and uncertain volume status are needed.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT02717533), first registered February 4, 2015.

Heart Failure Outcomes With Volume-Guided Management

OBJECTIVES

This study performed a retrospective outcome analyses of a large cohort of mixed ejection fraction patients admitted for acute heart failure (HF), whose inpatient care was guided by individual quantitative blood volume analysis (BVA) results.

BACKGROUND

Decongestion strategies in patients hospitalized for HF are based on clinical assessment of volume and have not integrated a quantitative intravascular volume metric.

METHODS

Propensity score control matching analysis was performed in 245 consecutive HF admissions to a community hospital (September 2007 to April 2014; 78 ± 10 years of age; 50% with HF with reduced ejection fraction [HFrEF]; and 30% with Stage 4 chronic kidney disease). Total blood volume (TBV), red blood cell volume (RBCV), and plasma volume (PV) were measured at admission by using iodine-131-labeled albumin indicator-dilution technique. Decongestion strategy targeted a TBV threshold of 6% to 8% above patient-specific normative values. Anemia was treated based on cause. Hematocrit (Hct) measurements were monitored to assess effectiveness of interventions. Control subjects derived from Centers for Medicare and Medicaid Services data were matched 10:1 for demographics, comorbidity, and year of treatment.

RESULTS

Although 66% of subjects had PV expansion, only 37% were hypervolemic (TBV >10% excess). True anemia (RBCV ≥10% deficit) was present in 62% of subjects. Treatment of true anemia without hypervolemia resulted in a rise in peripheral Hct of 2.7 ± 2.9% (p < 0.001), and diuretic treatment of hypervolemia in cases without anemia caused a 4.5 ± 3.9% (p < 0.001) increase in peripheral Hct at 11.3 ± 7.5 days after admission. Subjects had lower 30-day rates of readmission (12.2% vs. 27.7%, respectively; p < 0.001), of 30-day mortality (2.0% vs. 11.1%, respectively; p < 0.001), and of 365-day mortality (4.9% vs. 35.5%, respectively; p < 0.001) but longer lengths of stay (7.3 vs. 5.6 days, respectively; p < 0.001) than control subjects.

CONCLUSIONS

Retrospective outcomes using volume-guided HF therapy versus propensity-matched controls support the benefit of BVA in guiding volume management and reducing death and rehospitalization due to HF.