Bubble Chamber Clotting during Continuous Renal Replacement Therapy: Vertical versus Horizontal Blood Flow Entry

Abstract

Background: The continuous renal replacement therapy (CRRT) bubble trap chamber is a frequent site of clotting. Aims: To assess clot formation when comparing our standard ‘vertical’ blood entry chamber (BEC) with a new ‘horizontal’ BEC. Methods: Adult ICU patients requiring CRRT were treated with the vertical BEC and then a similar subsequent cohort with the horizontal BEC in continuous veno-venous haemofiltration mode. Results: 40 chambers were assessed for each design. Circuit life was 13.9 ± 9.5 h for the vertical and 17.7 ± 15.9 h for the horizontal BEC (p = 0.33). APTT, however, was higher for the horizontal BEC (55.7 ± 34.7 vs. 37.4 ± 9.0, p < 0.002) and no difference in circuit life was found after multivariable analysis. A clotting score ≥3 was observed in 85% of all chambers. There was no difference in chamber clotting score (vertical 3.6 ± 1.03 vs. horizontal 3.8 ± 1.0, p = 0.5). In addition, no difference was found when scores were divided into two groups using a ‘likelihood’ to clot analysis (p = 1.0). Conclusion: CRRT horizontal BEC were not associated with less clotting compared to our standard vertical BEC.

Non anti-coagulant factors associated with filter life in continuous renal replacement therapy (CRRT): a systematic review and meta-analysis

“…Two small studies showed no benefit from different sites of heparin delivery [ 55 , 56 ]. No benefit was observed using a modified horizontal bubble trap on the return line [ 57 ], priming the circuit with albumin before use [ 58 ] to improve biocompatibility or by the presence or absence of a fluid warmer on the return blood path [ 59 ].…”

Anticoagulation Effect and Safety Observation of Regional Citrate Anticoagulation for Double-Filtration Plasmapheresis in Critical Patients

“…The coagulation degree of plasma separator after treatment was divided into 4 classes [22,23]: Class I, 1-3 blood clots at the tip of the filter; Class II, annular blood clot at tip of filter; Class III, several large blood clots at the tip of the filter; and Class IV, completely coagulated on the lid. The degree of vein ampulla coagulation was divided into 5 classes [23]: Class I, no coagulation in vein ampulla after blood return; Class II, small clots in the filter at the bottom of vein ampulla; Class III, circular clots at the top of vein ampulla and clots at the bottom of the filter; Class IV, large clots on the upper and bottom of vein ampulla filter; and Class V, completely coagulation in the entire vein ampulla and requirement of replacement venous blood tube. Blood samples were collected from peripheral veins and arteries before and after treatment.…”

Continuous Renal Replacement Therapy Without Anticoagulation: Top Ten Tips to Prevent Clotting

“…The gas and blood interface, along with surface movement, causes cell smearing on the chamber walls. Adjustment of the blood level high in the chamber may reduce this by reducing blood splashing on the surface and coagulation [35,36].…”