I would like to suggest that damage be split into two components: Damage + Damage Over Time (a Wound)
Total damage should be determined by melee weapon type or by velocity and shot type as I assume it is now (although I only ever see 10 damage notice if I don't make an outright kill).
I suggest that a Wound persist for 20 seconds during which damage is regularly applied and the victim is Impaired, suffering a movement penalty and accuracy penalty.
Surgeons should be able to treat Wounds, removing the Impairment and healing the damage applied by the Wound, but NOT be able to heal the direct damage applied by the initial hit. I suggest this healing process take 10 seconds so no single surgeon could heal any two injured soldiers without one of their wounds running its course.
My preference would be to see this change made in conjunction with a small to moderate increase in accuracy. More accuracy would counteract the reduction in deaths caused by this change which would reduce overall damage.