A paragraph break is appropriate here (so Revised Standard Version).

Quickly some of Heliodorus‘friends asked Onias to call upon the Most High and to grant life to one who was lying quite at his last breath: To call upon the Most High may be rendered “to ask [or, pray to] the All-Powerful God.” To grant life to one who was lying quite at his last breath is what Heliodorus’ friends wanted Onias to pray for: that Heliodorus would regain consciousness and survive. Lying quite at his last breath means he was about to die. It is possible to reorder the clauses in this verse as follows:

• Heliodorus was about to die. So some of his friends quickly asked Onias the High Priest to pray to God Most High [or, All-Powerful] and ask him to let Heliodorus live.

Quoted with permission from Bullard, Roger A. and Hatton, Howard A. A Handbook on 1-2 Maccabees. (UBS Helps for Translators). New York: UBS, 2011. For this and other handbooks for translators see here.