Should be said daily from beginning of the illness through its duration whether or not our Lord Jesus decides to grant healing of the body or take you from this world.
LORD Jesus Christ, behold I receive this illness which Thou art pleased to give me from Thy fatherly hand. It is Thy Will for me, and therefore I accept it. Thy Will be done on earth, as it is in Heaven. May it be to the honor of Thy holy Name and the good of my soul. For this purpose I here offer myself with an entire submission to all Thy designs, to suffer whatever Thou dost please, as long as Thou dost please, and in what manner Thou dost please. For I am Thy creature, O Lord, who have most ungratefully offended Thee. And since my sins have for a long time called aloud to Heaven for justice, why shall I now complain if I feel Thy hand upon me? No, my God, Thou art just in all Thy ways; I have truly deserved Thy punishments, and therefore I have no reason to complain of Thee, but only of my own wickedness.
But correct me not, O Lord, I beseech Thee, in Thine anger, but have regard for my weakness. Thou knowest how frail I am, that I am nothing but dust and ashes. Deal not with me, therefore, according to my sins, nor punish me according to my iniquities, but according to the multitude of Thy most tender mercies, have compassion on me. Let Thy mercy come mixed with Thy justice, and let Thy grace be my support in my illness.
Confirm my soul with strength from above, that I may bear with patience all the uneasiness, pain, disquietude and difficulties of my illness, and that I may cheerfully accept them as the just punishment of my offenses. Preserve me from all temptations, and be Thou my defense against all assaults of the enemy, that in this illness I may in no way offend Thee.
And if this is to be my last illness, I beg of Thee so to direct me by Thy grace that I may in no way neglect or be deprived of those means which Thou hast in Thy mercy ordained for the good of my soul, to prepare it for its passage into eternity; that being perfectly cleansed from all my iniquities, I may believe in Thee, love Thee, put my whole trust in Thee, and through the merits of Thy Passion and Death, be admitted into the company of the Blessed, where I may praise Thee forever.
(Our Father, Hail Mary, Glory Be)