ISTANBUL, June 23, 2013 -- Originally from Homs, Dr. M. Zaher Sahloul is based in Chicago, where he practices critical care medicine and serves as the president of the Syrian American Medical Society. Over the past year, he has made seven trips to Syria. The last was to Aleppo, one month ago.

Every area is different in terms of the facilities available, and the supply shortages and types of injuries. In many urban areas like Aleppo, most of the physicians have fled, to Turkey and Jordan and other countries. There were about 2,000 doctors in Aleppo before the crisis, and that number is now down to 70. The area under opposition control, 50 percent of Aleppo, has 2 million civilians, 10 hospitals and only 70 practitioners.

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They're short of everything, from IV fluids to oral antibiotics to painkillers to anesthesia to surgical supplies, to electricity, phone lines, ambulances and diesel fuel to operate generators. Of course NGOs are trying to help them get the supplies, but you have to smuggle them across the Turkish border. Or sometimes you get it from other areas in Syria and transfer it to Aleppo. This operation is a logistical nightmare, especially if you want to transport things from Turkey or Jordan or Lebanon. Then there's the concern [when the supplies have been donated] of, how do you document that it was used for the purpose it was sent for?

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You have trained physicians dealing with things they're not trained to deal with. Like an internist might be the only doctor in town, and now he has to deal with surgical cases and amputations and people bleeding to death. So you at least have to give him a crash course in how to deal with that. We've been doing crash courses for Syrian doctors, providing them with medical supplies.

There are all kinds of cases where lives could have been saved with simple things like blood donations, the right transport equipment, or if you have a surgeon who can deal with the injury. A lot of people lose their limbs because there's no surgeon who can suture their muscles or no operating room to deal with a simple surgery that with time becomes very complicated. In medicine there's a "golden hour" to treat certain injuries, especially with patients who are bleeding [heavily]. And if you miss it, patients end up losing legs, arms, lives, because of delays of treatment. Patients used to be transferred to Turkish hospitals, and it took a few hours. Now it takes five days.

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One patient I saw was a 24-year-old mother whose home was shelled in the old city of Homs, which is about seven hours' drive from the Turkish border. When I saw her, she was in a rehabilitation unit in Antakya. She told me her home had been shelled, so she rushed out because there was a fire. Her left arm was hanging from her shoulder and bleeding profusely. She was taken to a primitive field hospital in the old city and they amputated her arm. She stayed there between life and death for 18 days because the old city was under siege [and she couldn't be moved elsewhere]. It still is.

Eventually they were able to smuggle her and her children out of the old city through an underground sewer system. Then it took five days to get to Turkey, and at that time she developed a huge infection in her body from her wound. She's 24, but after this she looks like she's in her 50s.

I also saw a 4-year-old child. Her house had been shelled in Idlib, and she had a spinal cord injury. She was moved to Turkey and had surgery but was not able to move her body. I tried to joke with her, to smile, I brought her a big stuffed bear. But she could not make a smile. She was very depressed, at four years old. And this is one of the thousands of patients you see.