Yes. Baptism by Blood is an Apostolic Catholic doctrine that has been articulated and taught for centuries.
Originally Posted by Patristic Arcana
"Let men of this kind, who are aiders and favourers of heretics, know therefore, first, that those catechumens hold the sound faith and truth of the Church, and advance from the divine camp to do battle with the devil, with a full and sincere acknowledgment of God the Father, and of Christ, and of the Holy Ghost; then, that they certainly are not deprived of the sacrament of baptism who are baptized with the most glorious and greatest baptism of blood". (St. Cyprian, Ep. LXXII)
"In truth we also have a second laver which is the same as the first, namely that of blood, concerning which Our Lord said, "And I have a baptism wherewith I am to be baptized' (Luke 12:50) after He had already been baptized; for He came by water and blood as John wrote, that He might be baptized by water and glorified by blood, likewise too that He might make us called by water and chosen by blood; He poured forth these two baptisms from the wound dug in His side so that those who believed in His blood might be cleansed by water and those who were cleansed by water might bear His blood; this is the baptism which takes the place of the laver which has not been received and restores what was lost." (Tertullian, De Baptisme)
If anyone does not receive baptism, he does not have salvation, excepting only martyrs who gain the kingdom even without water." (St. Cyril of Jerusalem, Enchiridion Patristicum, 811)
"Do not be surprised that I should equate martyrdom with baptism; for here too the spirit blows with much fruitfulness, and a marvellous and astonishing remission of sins and cleansing of the soul is effected; and just as those who are baptized by water, so, too, those who suffer martyrdom are cleansed with their own blood." (St. John Chrysostom, Panegyric on St. Lucianus)
17 Q: Can the absence of Baptism be supplied in any other way?
A: The absence of Baptism can be supplied by martyrdom, which is called Baptism of Blood, or by an act of perfect love of God, or of contrition, along with the desire, at least implicit, of Baptism, and this is called Baptism of Desire. (Catechism of St. Pius X)
The Church has always held the firm conviction that those who suffer death for the sake of the faith without having received Baptism are baptized by their death for and with Christ. This Baptism of blood, like the desire for Baptism, brings about the fruits of Baptism without being a sacrament. (CCC 1258)