LER, SUDAN -- Dr. Stephen Anyaak worked quickly on his patient, slicing through layers of flesh in the lower abdomen and straining, under a dim fluorescent light powered by a rusty car battery, to see signs of a ruptured hernia.

It had been a long, difficult night for the surgeon -- a cancerous eye had been removed from one peasant and a gangrenous finger from another. All the patients had lain on the same oversized refrigerator door that serves as an operating table here.

Now, as the doctor prepared to stitch up his latest case, he dreamed aloud of a few things that this remote, ill-supplied hospital could use. "Water, electricity, food, better anesthesia," Anyaak said, wiping rivers of sweat from his face and naked chest as strains of Arabic music poured from a cassette player. "But this is Sudan. It is better than working under a tree."

In the war-torn south of this East African country, virtually everything in life is relative. Patients who make it as far as the bloodstained refrigerator door of this man they call "The Good Butcher" can count themselves lucky, for they are among the very few out of the multitudes of civilians who need medical care.

This makeshift hospital in Ler -- the only one for hundreds of miles in a region of 500,000 people -- stands at the very front line of a coming catastrophe.

Meningitis is on the rise here, as well as severe malnutrition. Indeed, just two years after famine and famine-related diseases killed 250,000 civilians in southern Sudan, the country faces another famine in coming months that may affect as many as 8 million of the nation's 22 million people, according to relief experts in the region.

"We will run out of food by next month. When that happens, the hospital will have no reason to exist. We simply cannot work without being able to feed the people," said Andre Griekspor, a slender, 27-year-old Dutch physician working with a private Western organization that started this hospital two years ago.

Nearby, in the steamy night air outside the operating room's creaky wooden door, more than 300 victims of a disease called kala azar rested in pain in the darkness, some gasping for breath, their weakened bodies reduced to wrinkled skin and bones.

Kala azar is a vicious disease, caused by the bite of a sand fly, whose wasting effects are similar to those of AIDS. These victims represent the first wave of what is feared will be an epidemic of kala azar among the Nuer, Nuba and Dinka people of Sudan's Upper Nile, southern Kordofan and Bahr el Ghazal provinces.

Although kala azar can be treated at a cost of about $200 per patient with a European-made drug called pentostam, the hospital is nearly out of supplies. Doctors say many patients will die in coming weeks.

That the hospital -- a collection of colonial-era, ramshackle, stone and wooden buildings and cone-shaped thatched huts serving more than 4,000 patients a month -- continues to function at all is something of a miracle. The Western relief group that runs the hospital requested that it not be identified, because it operates in defiance of a strict ban on outside relief efforts in this region imposed recently by Gen. Omar Hassan Bashir's government in Khartoum, the capital.

The hospital, located in rebel-held territory, bravely endures, despite Sudan's civil war, which pits the predominantly Moslem government of the north against the Christian and animist south. Eight weeks ago, Ler and the hospital were bombed by several of the government's Soviet-made Antonov aircraft.

"When the Antonovs came," Dr. Griekspor said, "the people began to point at the sky and shout, 'Omar!' {after the Sudanese leader}. We had dug as many foxholes as we could, because the government has bombed this area before. But many didn't make it." Seven young people were torn apart by one bomb that exploded in a ball of fire near the hospital, he said.

"The people in the south have so many problems already," said Griekspor, who, like his young colleagues, came to Sudan to experience life in the Third World and to put their medical training to more effective and immediate use than they could in Europe. "But then you add this war to life here and it becomes so criminal, so senseless."

The medical workers still cannot get over the shock of seeing 10-year-old boys coming into the hospital with bullet wounds in their hands and feet, having shot themselves to avoid service in the rebel army.

Just 200 miles up the White Nile River, in the town of Bor, sits a $1 million barge capable of regularly carrying more than 60 tons of food and medical supplies downstream to the riverside town of Adok, an hour from Ler by truck. For four months, the barge, called the Red Cross II, has remained moored, blocked from moving on orders of the Bashir government, which fears it would be used by the rebels to ferry arms.

During these months, the barge has thrived in the imaginations of the people in Ler, who often speak about the wonders it can do, hoping for its imminent arrival -- and perhaps their own deliverance.

"We've talked about it so much. It represents hope to everyone. For a while we thought it would come at any moment," said Marjo Lein, a Dutch nurse, as she sat back late one recent night with her colleagues huddled in lamplight in a house draped with mosquito screens and netting.

"The supplies it could bring!" she said. "Salt, IV fluids, grain! We could even get beds. We don't have a single bed in the hospital except for the refrigerator door."

Were it not for the remarkable efforts of another visitor in the room that night, a sandy-haired, 44-year-old Texas native named Jim Gaunt, this fragile, makeshift hospital in the middle of nowhere would be isolated entirely from the outside world. The American, in fact, is as vital to this extraordinary medical operation as any doctor.

Every two or three weeks -- in defiance of a threat by Khartoum to shoot down relief aircraft in rebel areas -- Gaunt, a reconnaissance pilot in the Vietnam War, flies his four-seat, twin-propeller airplane into Ler from his base in Kenya with medical supplies and other provisions.

"Without him," said Lein, the nurse, "we would just not be here. Everything you see -- chairs, medicine, kerosene, even us -- were brought to Ler by Jim. . . . If anything happens to him, all of us will be in very bad shape."

The Texan says he is a mercenary by trade, paid at least $6,000 for every trip to Ler by the relief group that runs the hospital. "But I think I'm a good mercenary," said Gaunt. "I'm not killing people. I'm saving lives."

Recently, Gaunt, a son of Baptist missionary parents who spent part of his childhood in Africa, piloted Egil Hagen, director of a relief organization called Norwegian People's Aid, into southern Sudan.

Hagen wanted to assess the condition of the Red Cross barge in Bor and to find out the extent of disease and food shortages among the people downstream in Ler. Hagen intended to inform the Norwegian government of his findings and invited a reporter to join him on the trip.

The flight to Ler, lasting three hours over rebel territory, combined many of the features and hazards of humanitarian work and travel in Sudan. Plastic bags of new syringes, a repaired propeller shaft for a small river barge, a sack of mail and a case of Kenyan beer were among the items filling the small cargo hold of Gaunt's plane for the doctors and inhabitants here. The plane took off at dawn into a bright blue, cloudless sky, soaring over rugged plains sprinkled with herds of cattle and wild gazelle.

But shortly after crossing the Kenyan border into Sudan, the Texan geared for the realities of war, not relief, tuning the plane's radio to military channels and scanning the skies for Sudanese MiG fighter jets, believed to be based at the government-held southern city of Juba.

Should he see one, Gaunt told his passengers, "the only thing I can do is dive. That's it. Dive fast and try to land in any clearing I see down there."

Last year, a relief airplane carrying four French medical workers was shot down near the southern town of Aweil, reportedly by government missiles, killing all on board -- a tragedy Gaunt says he bears in mind whenever he travels near government-held towns.

A little later, as his 1961-vintage plane touched down at an airstrip in the rebel-held town of Kapoeta, Gaunt announced his safe arrival by radio to his wife and three daughters in Nairobi, without mentioning the site and tipping off anyone who might be listening to the frequency. He repeated this practice with each landing and takeoff, like any American husband calling home to the family, a habit that added an element of blithe routine to an otherwise tense and risky trip.

It wasn't until the plane reached Ler, however, that Gaunt seemed to relax, knowing he was approaching a home away from home. Following the twisting course of the White Nile, he began his descent from 6,000 feet just east of the town, slowly circling the rarely used airstrip.

Peering through sunglasses, Gaunt closely checked the strip for large rocks, pools of rainwater and other possible hazards. Then, at a gentle angle from the east, he came in swiftly, landing in a quick burst of red dust and streaking across pebbles, dirt and ankle-high weeds before coming to rest near a thicket of scrub brush at the end of the runway.

By the dozens, the people of Ler appeared, rushing forward toward the aircraft in the faint glow of sunset: Western medical workers, Nuer herdsmen, peasants, boys, all cheering and waving as the Texan turned off the engines.

"Hello, Mr. Jim!" an old man shouted, walking stick in hand, merrily clapping the pilot on the back as he clambered from the aircraft. Opening the cargo hold, the Texan pulled out the syringes, the plastic bags of intravenous fluids, the beer, the sack of mail and the propeller shaft as the people exulted.

"Now you see why I do this crazy job," Gaunt said, beaming.

That night, as Gaunt, Griekspor, Lein, Anyaak and the other medical workers sat in the lamplight, Hagen told them he would do his best to get the Red Cross II downstream with the supplies they need so badly. "I'm going to fly to Oslo next week and tell the Norwegian foreign minister that the government must do something. This is just a terrible waste," the relief official said.

The doctors and nurses nodded.

"We've got a kala azar patient who has a real bad case of tuberculosis, Jim. I don't know if he'll last another day or two," one of the Dutch nurses said to the American pilot after a moment of silence. "Do you think you can take him with you when you fly back to Torit? Maybe the hospital there can help."

"Sure," Gaunt said softly, taking a sip of the Kenyan beer. "I've got room for one more."