Use of Coagulation Point-of-Care Tests in the Management of Anticoagulation and Bleeding in Pediatric Cardiac Surgery: A Systematic Review.

Bleeding and coagulation management are essential aspects in the management of neonates and children undergoing cardiac surgery. The use of point-of-care tests (POCTs) in a pediatric setting is not as widely used as in the adult setting. This systematic review aims to summarize the evidence showed by the literature regarding the use of POCTs in children undergoing cardiac surgery. We included all studies examining the pediatric population (<18 years old) undergoing cardiac surgery in which the coagulation profile was assessed with POCTs. Three electronic databases (PubMed, Embase, and the Cochrane Controlled Clinical Trials register) were searched. Tests involved were heparin effect tests, viscoelastic tests, and platelet function tests. Due to the wide heterogeneity of the patients and tests studied, a formal meta-analysis was impossible, and the results are therefore presented through a systematic review. Eighty articles were found, of which 47 are presented in this review. At present, literature data are too weak to define POCTs as a "gold standard" for the treatment of perioperative bleeding in pediatric cardiac surgery. Nevertheless, introduction of POCTs into postoperative algorithms has shown to improve bleeding management, patient outcome, and cost efficiency.

Fibrinogen levels and postoperative chest drain blood loss in low-weight (<10 kg) children undergoing cardiac surgery.

INTRODUCTION: Low-weight (<10 kg) children undergoing cardiac surgery with cardiopulmonary bypass are prone to dilution and consumption of soluble coagulation factors and fibrinogen. Low levels of fibrinogen may represent a possible cause of severe postoperative chest drain blood loss. The present study investigates the association between post-cardiopulmonary bypass fibrinogen levels and postoperative chest drain blood loss and severe bleeding, aiming to identify possible cut-off values to trigger specific interventions. METHODS: Prospective cohort study on 77 patients weighing <10 kg undergoing cardiac surgery with cardiopulmonary bypass. Haemostasis and coagulation data were collected before surgery (standard tests and thromboelastometry), after protamine (thromboelastometry) and at the arrival in the intensive care unit (standard tests). The primary outcome variable was severe bleeding (chest drain blood loss >30 ml kg-1/24h). RESULTS: Factors being independently associated with severe bleeding were the international normalized ratio and the fibrinogen levels at the arrival in the intensive care unit. Once corrected for other confounders, fibrinogen levels had an odds ratio of 0.2 (95% confidence interval = 0.011-0.54) per 1 gL-1 for severe bleeding. The discrimination power was fair (area under the curve = 0.770). The best cut-off value was identified at a fibrinogen level of 150 mg dL-1, with a sensitivity of 52%, a specificity of 85% and a positive predictive value of 60% for severe bleeding. CONCLUSION: Both a prolonged international normalized ratio and low fibrinogen levels were predictive for severe bleeding, underscoring the role of coagulation factors dilution and consumption in this specific patient population.

Safety and efficacy of citrate anti-coagulation continuous renal replacement therapies in post-cardiac surgery patients with liver dysfunction.

The study's aim was to examine safety and efficiency of citrate anticoagulated continuous renal replacement therapies (CRRT) in cardiac surgery patients with acute kidney injury and associated liver dysfunction. The study was conducted on critical ICU patients, hospitalized after cardiac surgery, who developed renal and liver acute failures due to low-flow syndrome. CRRT in continuous veno-venous hemodiafiltration with regional citrate anticoagulation (RCA) was prescribed to address renal failure and avoid bleeding-risk. Patient Ca(++) was measured to monitor RCA safety, while thromboelastography (TEG) and circuit Ca(++) were used to verify efficacy. CRRT effectiveness was evaluated through creatinine and urea levels, while liver function was monitored through bilirubin, aspartate aminotransferase, glutamic oxaloacetic transaminase (AST GOT) and gamma glutamyl transferase (GT) levels. The study did not require ethical approval. Hepatic and renal failures were confirmed by baseline levels (total bilirubin=3.1 ± 3.37 mg/dL, AST GOT=153 ± 147 U/L and gamma GT=93.3 ± 86 IU/L, creatinine=1.97 ± 0.88 and blood urea nitrogen [BUN] 98.13 ± 71.34) assessed in 15 patients. During treatment, Ca(++) (patient and circuit) remained stable and within range for the whole therapy thanks to low citrate dose (2.8 ± 0.3 mmol/L of blood), while hepatic markers did not show any significant changes the therapy, although treatment with citrate is contraindicated in patients with hepatic failure. RCA quality was confirmed by TEG values, which showed an anticoagulated circuit with no effects on patients. These results involved a high filter lifespan (49.76 ± 22.10 h) and with an effective creatinine and BUN clearance. No episodes of citrate intoxication were reported (total/ionized calcium ratio remained stable and physiologic). RCA during CRRT with dilute solutions proved both effective and safe, even in patients with acute liver failure.