Hedging Costly And Unlikely Events With More Than Conventional Insurance

The selling proposition of something like an inflation-adjusted annuity is that the purchaser trades uncertainty for certainty. Even though some simple calculations will show that fixed and regular real withdrawals while assuming historically poor future performance usually beats most annuity products, some are interested in trading in that 99.9% probability for a 100% (for all intents and purposes) guarantee of future income.

While an Inflation-Protected Annuity (IPA) provides tail-risk protection on the income side, I am wondering if there are similar products that provide tail-risk protection on the expense side, namely for things like unexpected and costly medical expenses or lawsuits. I currently have a great health insurance plan and an umbrella policy as well, but I am curious about true, 100% coverage (i.e. no policy limits, no deductibles, no copays, etc.) options, if they exist.

Obviously such products would be much more costly to the policy-holder, but it is the same idea as an IPA; some subset of the population would be happy to trade a less-expensive 99.99% probability that conventional plans are plenty good enough for a 100% guarantee of coverage.