The Effect of Albumin Administration in Critically Ill Patients: A Retrospective Single-Center Analysis

OBJECTIVES

The aim of this study was to analyze the development of albumin administration in patients admitted to the adult ICU. In addition, we assessed the impact of albumin administration on serum hemoglobin concentration.

DESIGN

We conducted a retrospective single-center study including all patients who were admitted to the ICU from January 2013 to December 2021 and stayed at least 24 hours.

SETTING

The study was conducted in an academic hospital (University Hospital Basel, Switzerland).

PATIENTS

A total of 20,927 admissions were included, of which 3748 received albumin at least once during their ICU stay. To analyze volume expansion, 2006 admissions met the inclusion criteria, namely at least two hemoglobin measurements within 12 hours, one albumin delivery, and experienced no bleeding, dialysis, or transfusions during this period.

INTERVENTIONS

None.

MEASUREMENTS

We examined the hemoglobin levels before and after albumin administration and compared them with a matched control group to assess the amount and duration of volume expansion.

MAIN RESULTS

From 2013 to 2021 the proportion of critically ill patients treated with albumin rose from 5.0% to 32.5%. An overproportioned increase in albumin use could be seen in surgical patients (4.7-47.2%) and in those receiving RBC transfusion (13.7-72.6%). In those patients receiving albumin, a significant drop in hemoglobin of around 5 g/L on average could be observed following treatment with albumin.

CONCLUSION

Hemodilution was observable for at least 12 hours after albumin administration and may have caused a decrease in hemoglobin concentration of greater than 8 g/L when isooncotic albumin solution (5%, 25 g in 500 mL) was administered. This makes albumin, especially in its isooncotic form, an ideal colloid to achieve long-lasting volume expansion. However, RBC transfusions may increase under albumin therapy, as transfusion thresholds may be undershot after albumin administration.

Impact of Additional Administration of von Willebrand Factor Concentrates to Thrombocyte Transfusion in Perioperative Bleeding in Cardiac Surgery

Background

Von Willebrand factor (vWF) is an important part of blood coagulation since it binds platelets to each other and to endothelial cells. In traumatic and surgical haemorrhage, both blood cells and plasmatic factors are consumed, leading to consumption coagulopathy and fluid resuscitation. This often results in large amounts of crystalloids and blood products being infused. Additional administration of vWF complex and platelets might mitigate this problem. We hypothesize that administration of vWF concentrate additionally to platelet concentrates reduces blood loss and the amount of blood products (platelets, red blood cells [RBC], fresh frozen plasma [FFP]) administered.

Methods

We conducted a monocentric 6-year retrospective data analysis of cardiac surgery patients. Included were all patients receiving platelet concentrates within 48 h postoperatively. Patients who additionally received vWF concentrates were allocated to the intervention group and all others to the control group. Groups were compared in mixed regression models correcting for known confounders, based on nearest neighbour propensity score matching. Primary endpoints were loss of blood (day one and two) and amount of needed blood products on day one and two (platelets, RBC, FFP). Secondary endpoints were intensive care unit (ICU) and in-hospital length of stay, ICU and in-hospital mortality, and absolute difference of platelet counts before and after treatment.

Results

Of 497 patients analysed, 168 (34%) received vWF concentrates. 121 patients in both groups were considered for nearest neighbour matching. Patients receiving additional vWF were more likely to receive more blood products (RBC, FFP, platelets) in the first 24 h after surgery and had around 200 mL more blood loss at the same time.

Conclusion

In this retrospective analysis, no benefit in additional administration of vWF to platelet concentrates on perioperative blood loss, transfusion requirement (platelets, RBC, FFP), length of stay, and mortality could be found. These findings should be verified in a prospective randomized controlled clinical trial (www.clinicaltrials.gov identifier NCT04555785).

FLT3 ligand gene expression and protein production in human colorectal cancer cell lines and clinical tumor specimens

Dendritic cells (DC) are professional antigen presenting cells (APC) whose proliferation and functional differentiation can be induced by hematopoietic growth factors including GM-CSF and FLT3 ligand (FL). Colorectal cancers are known to be infiltrated by dendritic cells (DC) and neoplastic cells have been shown to produce GM-CSF. In this work we investigated FLT3 ligand (FL) gene expression and protein production in human colorectal cancer cell lines and clinical tumor specimens. Using reverse transcription polymerase chain reaction (RT-PCR), 6 out of 6 established tumor lines were found to express to variable extents FL gene. In 1 of them, SW480, FL immunoreactivity could be observed by taking advantage of specific antibodies. In contrast, soluble FL could not be detected in any culture supernatant. FLT3 receptor (FR) gene was not expressed and exogenous addition to the cultures of recombinant FL (rFL) did not affect the proliferation of the tumor lines. FL gene expression was investigated using a densitometry-assisted, semiquantitative RT-PCR in clinical tumor specimens. Specific FL gene transcripts were amplified from 12 of 12 surgical samples. In these cases, FL gene expression of significantly lower intensity was also detected in healthy mucosa sampled in the vicinity (2 cm) or at a distance (10 cm) from neoplastic outgrowth. Immunohistochemical studies identified FL-positive cancer cells in 5 of 5 cases tested. No positivity was detected in healthy mucosa epithelia at a distance from the tumor or in stromal cells. FL content in preoperative sera from colorectal cancer patients (n = 13) did not exceed the levels detected in healthy donors (</= 100 pg/ml).

GM-CSF gene expression and protein production in human colorectal cancer cell lines and clinical tumor specimens

Granulocyte-macrophage colony stimulating factor (GM-CSF) gene expression and protein production were investigated in colorectal cancer cell lines and surgical specimens. In 6 of 6 established tumor lines, expression of the GM-CSF gene was observed by reverse transcription polymerase chain reaction (RT-PCR). Furthermore, for 2 of the lines, the cytokine was detectable in > or = 100 pg/ml amounts in culture supernatants by enzyme-linked immunosorbent assay tests. Addition of recombinant GM-CSF at doses ranging between 30 pg and 30 ng/ml did not appear to affect the proliferation of colorectal cancer cell lines as measured by 3H-thymidine incorporation. GM-CSF gene expression was then examined in surgical specimens by a densitometry-assisted, semiquantitative RT-PCR technique. In the 10 samples analyzed, significantly higher expression was detectable in tumors, as compared with autologous healthy mucosa sampled in the vicinity (2 cm) or at distance (10 cm) from the neoplastic focus. Immunohistochemistry studies performed on 13 specimens led to the identification of intracytoplasmic GM-CSF in tumor cells in 9 samples. In 6 of these, positivity of stromal fibroblasts and lymphocytes adjacent to the tumor was also observed. In contrast, intracellular GM-CSF was only detectable in 2 cases in untransformed epithelial cells, close to the neoplasm, but never in healthy mucosa at distance from the tumor. Infiltration by dendritic cells (DC) was also investigated. In 5 of 8 colorectal cancers tested, DC aggregates accounted for more than 10% of stromal cells. Lower numbers were detectable in healthy mucosa. However, DC infiltration could not be correlated with the presence of GM-CSF-positive neoplastic cells in the tumor specimens. Remarkably, cultured DC were unable to exert significant cytotoxic activity against colorectal cancer cells in vitro.

The lymphatics of the liver

An overview of our current knowledge of the hepatic lymph vessels is given, and the different lymph node stations that are related to the liver are described. The lymphatics of the liver itself can be divided into a superficial and a deep system. The superficial vessels are mainly situated in the liver capsule, the deep ones follow the triads of Glisson or the efferent hepatic veins. There are no direct communications between spaces in the liver parenchyma and the first lymphatic capillaries, which end blindly in the surrounding connective tissue. Nevertheless, the perisinusoidal space of Disse, the space of Mall, directly adjacent to the outer limiting plate of the parenchyma, and the space of Comparini, surrounding the sublobular hepatic veins can be regarded as prelymphatic spaces from which the hepatic lymph could originate. The extracellular matrix in the space of Disse is apparently continuous with the extraparenchymal areas of the connective tissue. Collagens and proteoglycans offer a morphological pathway for the transport of fluid, the physiological prerequisites of which are discussed.

[Open therapeutic trial of anti-T CD4 monoclonal antibody in multiple sclerosis]

Twenty-one patients with active multiple sclerosis (16 progressive and 5 recurrent forms) were treated with murine monoclonal anti-T CD4/BF5 antibodies in an open trial. Tolerance was relatively good; 11 patients had side effects including facial swellings, skin eruptions and trembling which occurred only at the first infusion. Treatment had to be stopped in one female patient. Nine months after initiating treatment, no relapse had occurred in any of the 5 patients with a recurrent form and improvement was observed in 3 patients with a progressive form. At the end of the treatment period, there was a clear drop in the number of CD3+ cells and particularly in CD4+ cells, a decrease which was less after one month. All the patients who had side effects showed an increased level of serum IL6 and alpha TNF. These findings demonstrate that this type of long-term treatment is possible in patients with multiple sclerosis and suggest that in another trial it would be important to evaluate the effect in recurrent forms.