Here are some highlights of the catastrophic-illness insurance bill signed by President Reagan on Friday.

HOSPITAL - Full coverage for 365 days a year of hospital bills after a once-a-year deductible estimated at $564 in 1989. The deductible is indexed to rising hospital costs. Medicare now charges a deductible for each hospital stay during a year and provides full payment for just 59 days a year.DOCTOR BILLS - Full payment of "reasonable and proper" doctor bills after a $1,370 annual cap is met. Medicare continues to pay 80 percent of charges after a $75 deductible. Both the initial deductible and the 20 percent patient co-payment will count toward the $1,370 cap. Patient remains responsible for that portion of fees that exceed the amount allowed by Medicare.

DRUGS - Medicare pays 50 percent of outpatient drug costs, after a $600 annual deductible, starting in 1991. Medicare pays 60 percent the following year and 80 percent in 1993 and thereafter, with the deductible to be indexed to rising drug costs. Medicare now has no across-the-board prescription drug coverage.

COSTS - To be paid solely by Medicare beneficiaries. Current Part B premium of $24.80 to increase by $4 a month in 1989. By 1993, the "catastrophic" monthly premium is projected at $10.20, in addition to whatever the regular Part B premium is at that time. More than 60 percent of total program costs are to be financed by an additional supplemental premium that is linked to federal income tax liability. The supplemental starts at $22.50 a year per $150 of tax liability in 1989, rising to $42 a year per $150 of tax liability in 1993. There is an $800 cap per covered person on the total supplemental premium in 1989, rising to $1,050 in 1993.

NURSING HOME - Expands number of days per year for skilled nursing facility care from 100 days to 150 and reduces co-payment from $67.50 a day after 20th day to $20.50 a day for first eight days, then none. No provision for long-term custodial care.

RESPITE CARE - 80 hours per year home health services to relieve unpaid care providers. This is a new benefit.

HOME HEALTH CARE - Expands present coverage of up to three weeks of care per illness for five days per week to up to 38 days of care per ilness for seven days per week.

HOSPICE CARE - Expands present 210 days per year to 365 days per year as long as patient is certified as terminally ill.

MAMMOGRAMS - A mammogram examination every other year for women over 65. This is a new benefit. Payment initially will be limited to $50.

MEDICAID - The bill phases in, over four years, a requirement that state Medicaid programs pay all Medicare premiums, deductibles and co-payments for the elderly and disabled with incomes below the federal poverty line but too high to qualify for Medicaid coverage. This improvement varies widely from state to state depending on what the state already does.

SPOUSAL IMPOVERISHMENT - Gradually raises the income that may be retained by a spouse remaining in the community when the husband or wife has to go to a nursing home at Medicaid expense. Starting Oct. 1, 1989, the spouse at home can keep at least $786 per month, or 122 percent of the federal poverty level for a two-person family. Spouse is also allowed to keep up to $12,000 in liquid assets.