https://www.gamespot.com/articles/black-ops-4-update-patch-notes-cover-changes-to-bl/1100-6462529/

The first update for Call of Duty: Black Ops 4 has arrived. It introduces changes, tweaks, and fixes across the shooter's three main modes: Blackout, Zombies, and Multiplayer, with Zombies getting the bulk of the attention in the form of a notable balance pass.

The update increases player health for Casual, Normal, and Hardcore difficulty options by 50 points, which should help you survive longer. Developer Treyarch has also made adjustments how fast you earn points and to the cost of shield repair/replacement, among other things.