Related Factors of Anemia in Critically Ill Patients: A Prospective Multicenter Study

The incidence and factors associated with anemia in elective surgical patients admitted to a surgical intensive care unit: a retrospective cohort study

BACKGROUND

Anemia is a frequently reported and commonly documented issue in intensive care units. In surgical intensive care units, more than 90% of patients are found to be anemic. It is a hematologic factor that contributes to extended mechanical ventilation, sepsis, organ failure, longer hospitalizations in critical care units, and higher mortality. Thus, this study aimed to determine the incidence and identify factors associated with anemia in elective surgical patients admitted to the surgical intensive care unit.

METHODS

A retrospective follow-up study involving 422 hospitalized patients was carried out between December 2019 and December 2022 in the surgical intensive care unit after elective surgery at Tikur-Anbessa Specialized Hospital, Addis Ababa, Ethiopia. Data were gathered from the patients' charts, and study participants were chosen using methods of systematic random sampling. SPSS 26 (the statistical software for social science, version 26) was used to analyze the data. Bivariable and multivariable binary logistic regression were used to examine associations between variables.

RESULTS

The incidence of anemia in elective surgical patients admitted to the intensive care unit was 69.9% (95% CI 65.4-74.5%). American Society of Anesthesiologists' class III (ASA III) [AOR: 8.53, 95% CI 1.92-13.8], renal failure [AOR:2.53, 95% CI (1.91-5.81)], malignancy [AOR: 2.59, 95% CI (1.31-5.09)], thoracic surgery [AOR: 4.07, 95% CI (2.11-7.87)], urologic surgery [AOR: 6.22, 95% CI (2.80-13.80)], and neurosurgery [AOR: 4.51, 95% CI (2.53-8.03)] were significantly associated with anemia in surgical patients admitted to the intensive care unit.

CONCLUSION

More than two-thirds of the intensive care unit-admitted surgical patients experienced anemia. An American Society of Anesthesiologists' (ASA III score), renal failure, malignancy, thoracic surgery, urologic surgery, and neurosurgery were significantly associated with this condition. Early identification helps to institute preventive and therapeutic measures.

Effectiveness of closed blood sampling systems in intensive care patients: a scoping review

BACKGROUND

Anemia associated with blood extraction for diagnostic purposes is a highly prevalent entity in intensive care units (ICU) for adults. The evidence recommends its prevention through different strategies, among which we can find the use of closed blood sampling systems (CBSS). Different experimental studies support the use of these devices.

OBJECTIVE

To identify knowledge gaps regarding the effectiveness of CBSS in ICU patients.

METHODS

Scoping review with search in PubMed, CINAHL, Embase, Cochrane Library and Joanna Briggs Institute databases, between September-2021 and September-2022. No time, language, or other limits were applied to ensure the recovery of all relevant studies. Gray literature sources: DART-Europe, OpenGrey and Google Scholar. Two researchers independently reviewed titles and abstracts and assessed full texts against the inclusion criteria. The following data was extracted for each study: design and sample, inclusion and exclusion criteria, variables, type of CBSS, results and conclusions.

RESULTS

18 articles were included in the final review, 11 clinical trials (RCTs) published between 1992 and 2014. Three systematic reviews were found, but they only analyzed the effect of CBSS in reducing blood loss, hemoglobin stabilization, and the need for transfusion. Five of the RCTs analyzed the risk of infection, one catheter complications, and two alterations in blood pressure readings.

CONCLUSIONS

The use of CBSS is recommended to reduce blood loss in ICUs. However, there are discrepancies about their ability to prevent anemia and/or the need for blood transfusion. Its use does not increase catheter-related infection rates or alter the measurement of mean arterial pressure.

Routine Versus On-Demand Blood Sampling in Critically Ill Patients: A Systematic Review

OBJECTIVES

We aimed to provide an overview of the current evidence on routine versus on-demand blood sampling in critical care. We assessed the reported proportion of patients exposed to daily routine blood sampling, the tests performed, characteristics associated with more frequent blood sampling, and the reported benefits and harms of routine blood sampling compared with on-demand sampling.

DATA SOURCES

We systematically searched the Cochrane Library, the Excerpta Medica Database, and the Medical Literature Analysis and Retrieval System Online for studies assessing routine versus on-demand blood testing in critically ill patients from inception to September 2022.

STUDY SELECTION

Abstracts and full texts were assessed independently and in duplicate by two reviewers.

STUDY EXTRACTION

Data were extracted independently and in duplicate by two reviewers using predefined extraction forms.

DATA SYNTHESIS

Of 12,212 records screened, 298 full-text articles were assessed for eligibility. We included 70 studies; 50 nonrandomized interventional studies and 20 observational studies. Exposure to routine blood testing was 52-100% (very low certainty of evidence). Blood testing seemed to occur more frequently in medical intensive care settings with a median of 18 blood tests per patient day (interquartile range, 10-33) (very low certainty of evidence). Mixed biochemistry seemed to be the most frequently performed blood tests across all settings (five tests per patient day; interquartile range, 2-10) (very low certainty of evidence). Reductions in routine blood testing seemed to be associated with reduced transfusion rates and costs without apparent adverse patient outcomes (low certainty of evidence).

CONCLUSIONS

In this systematic review, routine blood testing in critically ill patients was common and varied considerably. A reduction in routine blood testing appeared to be associated with reduced transfusion rates and costs without adverse effects, but the evidence was very uncertain.

Evaluation of a closed loop-blood sampling system in intensive care: A pilot randomised controlled trial. The ENCLOSE trial

OBJECTIVE

To test the feasibility of conducting a randomised controlled trial to evaluate the impact of a closed-loop blood sampling system and blood conservation bundle.

METHODS

Single site, parallel group, pilot randomised control trial comparing open system sampling to closed system sampling and conservation bundle aligned with national guidelines. Randomisation sequence was generated by an independent statistician and allocation concealment maintained via sealed opaque envelopes. The study setting was the general intensive care unit of a major metropolitan public hospital in Queensland, Australia. Participants were ≥ 18 years who had an arterial catheter inserted in intensive care. Main outcome measures included trial feasibility, blood sample loss, haematocrit (HCT) change, and packed red blood cell transfusion use.

RESULTS

Eighty patients were randomised (n = 39 open group, n = 41 closed group). Characteristics in each group were equal at baseline with overall median age 60 years (IQR 48.6-70.4), 58 % male, and median APACHE II score 16 (IQR 11-22). The proportion of patients eligible was 29 % and missed eligible was 65 %. Otherwise, feasibility criteria were met with proportion of eligible patients agreeing to enrolment 99 %, 100 % of patients receiving allocated treatment; only 1 % of data missing. Analysis demonstrated a significant reduction in mean daily blood sample losses (open 32.7 (SD 1.58) mL vs closed 15.5 (SD 5.79) mL, t = -8.454, df = 78, p < 0.001).

CONCLUSIONS

A large, multi-site trial is feasible with enhanced eligibility criteria, increased recruitment support. The intervention reduced daily blood sample volumes and transfusion use. Further trials are required to provide both effectiveness and implementation outcomes.

Artificial Liver Support with CytoSorb and MARS in Liver Failure: A Retrospective Propensity Matched Analysis

Background: Liver failure represents a life-threatening organ dysfunction with liver transplantation as the only proven curable therapy to date. Liver assist devices have been extensively researched to either bridge such patients to transplantation or promote spontaneous recovery. The aim of our study was to compare two such devices, the Molecular Adsorbent Recirculating System (MARS) and CytoSorb, in patients with liver failure. Methods: We retrospectively included 15 patients who underwent MARS during their intensive care unit stay and matched them to 15 patients who underwent hemoadsorption using CytoSorb. Clinical and paraclinical data obtained after each individual session, after the course of treatment, as well as at the end of the intensive care unit stay were compared between the two groups. Results: Single sessions of CytoSorb and MARS were both associated with a significant decrease in bilirubin (p = 0.04 and p = 0.04, respectively) and ammonia levels (p = 0.04 and p = 0.04, respectively), but only CytoSorb therapy was associated with a decrease in lactate dehydrogenase levels (p = 0.04) and in platelet count (p = 0.04). After the course of treatment, only CytoSorb was associated with a significant decrease in lactate (p = 0.01), bilirubin (p = 0.01), ammonia (p = 0.02), and lactate dehydrogenase levels (p = 0.01), while patients treated with MARS did not show any improvement in paraclinical liver tests. In addition, only CytoSorb treatment was associated with a significant improvement in the Model for End-Stage Liver Disease Score (p = 0.04). Conclusion: In conclusion, our results show a potential benefit of CytoSorb in rebalancing liver functional tests in patients with liver failure compared to MARS but the exact effects on patient outcome, including hospital length of stay and survival, should be further investigated in randomized control trials.

The Dysregulation of the Renin–Angiotensin System in COVID-19 Studied by Serum Proteomics: Angiotensinogen Increases with Disease Severity

(1) Background: ACE and CPN serum activity correlated with disease severity in an earlier study of 45 hospitalized COVID-19 patients. The serum protein profile was investigated in the same cohort here to shed more light on the involvement of the renin–angiotensin system (RAS). (2) Methods: High-definition mass spectrometry-based protein expression analysis was performed, followed by multivariate statistical and network analyses. (3) Results: The protein profiles of hospitalized patients (HoP) differed significantly from those of convalescent and healthy probands. Surprisingly, HoP samples separated into six groups according to their protein profiles: group (G) 1 represented the youngest and the least afflicted patients, and G6 the oldest and critically ill patients. At least two major pathophysiological schemes were indicated based on differing involvement of the kallikrein-kinin system (KKS), the RAS and complement activation. The serum angiotensinogen concentration increased with disease severity. (4) Conclusions: The important role of the RAS in the response to COVID-19 infection was substantiated, but other pathways such as the KKS, plasminogen activation and complement activation influence the systemic response to the infection.