J Extra Corpor Technol 2024 , 56 , 125 – 127 Ó The Author ( s ), published by EDP Sciences , 2024 https :// doi . org / 10.1051 / ject / 2024021
Available online at : ject . edpsciences . org
CASE REPORT
Cardiopulmonary bypass in a pediatric patient with factor XII deficiency
Julie M . Fenske ( MS , CCP , FPP ) * , Julie Tinius Juliani ( MHA , CCP , FPP ), and Cynthia Herrington ( MD )
Children ' s Hospital Los Angeles , 4650 Sunset Blvd , Los Angeles , CA 90027 , USA Received 10 April 2024 , Accepted 22 July 2024
Abstract – The safe use of cardiopulmonary bypass ( CPB ) relies upon the ability to administer , monitor , and reverse anticoagulation . Although rare , the factor XII deficient patient creates a challenge for the perfusionist due to resultant complications in monitoring anticoagulation . There have been proposed strategies to aid in monitoring anticoagulation in factor XII deficient patients , however , documentation of successful monitoring during CPB is infrequent . With the use of the Hemochron Signature Elite and ACT + cartridges , CPB in a factor XII deficient 8-month-old was completed with predictable and reliable anticoagulation monitoring . This case report explores the current suggestions for factor XII deficiency management with CPB .
Key words : Cardiopulmonary bypass , Perfusion , Factor XII , Deficiency , Coagulopathy , Anticoagulation , Pediatrics .
Overview
Factor XII , also known as the Hageman factor , was first identified in 1955 when a patient ’ s blood failed to demonstrate normal clotting in glass sample tubes [ 1 ]. This patient , John Hageman , turned out to be deficient in factor XII and this discovery catalyzed the 1964 “ waterfall ” model of coagulation by Dr . Davie and Dr . Ratnoff [ 2 ]. Factor XII was later described as one of the plasma serine proteases collectively referred to as the contact system responsible for the activation of the intrinsic pathway of coagulation [ 3 ]. Factor XII is responsible for multiple processes , including activating factor XI , prekallikrein , and C1 esterase , as well as vasodilation and increased vascular permeability [ 4 ]. Understanding developmental hemostasis suggests that most procoagulant factors are low in infancy due primarily to liver immaturity , but reach adult levels by 6 months of age , [ 5 – 7 ].
Factor XII deficiency is normally asymptomatic , and is estimated to occur in approximately one in one million people , [ 1 , 8 ] although another study found up to 2.3 % of the population to be deficient in factor XII [ 9 ]. It is most often an autosomal recessive disorder but may also be autosomal dominant [ 3 , 8 ], and may be heterozygous or more severely homozygous [ 1 ]. Deficiency of factor XII is associated with prolonged anticoagulation measures including activated partial thromboplastin time ( aPTT ) and activated clotting time ( ACT ), as these tests measure the intrinsic clotting cascade ( Conaglen ). However ,
* Corresponding author : julie . fenske @ med . usc . edu contrary to what is implied with these prolonged anticoagulation measures , factor XII deficient patients do not demonstrate an increase in bleeding time [ 3 , 10 , 11 ].
It is worth mentioning that some studies suggest that there may be an increased risk of thromboembolic complications in factor XII deficient patients [ 8 , 12 ]. This is thought to be because factor XII is responsible for the conversion of plasminogen into plasmin therefore initiating the fibrinolysis process , however , the relationship between factor XII deficiency and thrombosis is yet to be fully understood [ 1 ]. Notably , the life of John Hageman , who was the novel patient afflicted with factor XII deficiency , came to an end after complications from a pulmonary embolism [ 1 ].
Description
An 8-month-old male with a history of VACTERL syndrome , complete tracheal rings # 3-8 , congenital tracheal stenosis , recurrent tracheal granulomas , and previous cardiac arrest with resuscitation presented for tracheal reconstruction with cardiopulmonary bypass . Coagulation tests performed one month before the operative date revealed a critically low factor XII value of 16.6 % ( expected range 50 – 150 %) and a high partial thromboplastin time ( PTT ) of 46 s ( expected range 25 – 35 s ) [ 1 ]. Prothrombin time ( PT ) of 13 s and the fibrinogen level of 253 mg / dL were within normal range .
An International Technidyne Corporation ( ITC ) Hemochron Signature Elite and ACT + cartridges were used
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