May 23, 1982

Mayor Koch yesterday established new guidelines aimed at reducing the diversion of emergency ambulances that carry heart attack victims to hospital emergency rooms and coronary-care units in New York City. Hospitals have refused to accept some ambulances because of overcrowding.The guidelines establish strict conditions for diversions and time limits on any delay in care resulting from them. The Mayor said the new guidelines were ''a responsible beginning for our continuing efforts to safeguard the effectiveness of the city's 911 emergency medical system.''

AUDREY HOCHBERG's decision to seek election to the State Assembly from a newly formed 86th District, which includes Scarsdale, where she lives, as well as White Plains and three-quarters of New Rochelle, apparently has cleared the Democratic field - except for Paul Feiner, also of Scarsdale, who made his bid official last week, too. Mr. Feiner, a 26-year-old lawyer and political gadfly, would seem to have little chance to succeed against Mrs. Hochberg, a six-term County Legislator, but politicians and others have learned not to scoff at the activist's efforts, no matter how long the odds. In this primary race, the odds against him are long, indeed. He is challenging an established and well-liked Legislator who has won reelection by wide margins. With Democratic district leaders lined up against him, he will have to seek nomination through the costly and time consuming petition process, rather than through designation.

LONDON PRIMARY principles of modern war on which vast modern military establishments are based are under test in the battle raging on, above and around the Falkland Islands. The outcome of this small, savage war between Britain and Argentina can answer some of the rude questions that trouble the mystique of sea power and perhaps much more. The Royal Navy has exercised its power traditionally, projecting strength 8,000 miles from home bases to enforce a blockade and support an invasion. The operation differs little in concept, but much in strength, from the amphibious campaigns waged by Adm. Chester Nimitz and Gen. Douglas MacArthur four decades ago in the Pacific. The essential difference lies in the introduction of radar-controlled missiles and torpedoes. These Exocets, Stingrays, Rolands and Rapiers are the highly sophisticated descendants of the ''smart bombs'' first used in Vietnam and the second generation of missiles employed in the Arab-Israeli war of 1973.

LIDO BEACH AMONG other unmistakable signs announcing the beach season's arrival has been the continuing escalation of a controversy between Nassau County and cabana renters at Nassau Beach over the status of 498 deteriorated cabanas here. For over seven years cabana renters, seeking to have the 35-year-old units upgraded, have been engaged in on-and-off litigation with the county to determine whether the units should be rehabilitated or destroyed. The issue boiled over again last week when the County Board of Supervisors voted unanimously to spend about $277,000 in general funds to repair the units and improve the grounds, over the objections of Francis T. Purcell, the County Executive, who wants the cabanas torn down. Mr. Purcell vowed to veto the measure within the week. The veto would be the first invoked by the Nassau County Executive in his five years in office. Mr. Purcell said he expected the veto to be overridden.

NEW LONDON CONNECTICUT COLLEGE has begun the largest fund-raising effort in its history and the most significant change in academic direction - and marketing strategy - since admitting men 13 years ago. Administrators, alumni and many faculty members see the four-year, $30 million Campaign for Connecticut College as the greening - in terms of diversity and dollars -of the 1,600-student liberal arts college on the banks of the Thames River. But to a persistent, if apparently smaller, number of student and faculty critics, the campaign is a sell-out. Although they support the initatives for increasing financial aid for students and salaries for the faculty, they contend that the program recommended by the Committee of Connecticut's Future would shortchange the humanities to strengthen mathematics, sciences and athletics. ''I really see the campaign as the responsibility of the college in the 1980's,'' said Oakes Ames, the president of the college since 1974. ''If we are successful - and I trust we will be - Connecticut College will be even more attractive than it is today.''