This article first appeared in the Wall Street Journal

I thought I was going to die when the earth shook. I was at Pacot, the [MSF] physical rehabilitation center in Port-au-Prince. Five minutes after the quake, people were banging on our door in need of help. There were four of us, including a fourth year nursing student with minor injuries, and we worked all night. The janitor helped with bandages. It was quickly overwhelming from a medical standpoint: Within a few hours there were hundreds of people in need of surgery. I see some people and can't believe they are alive. They have extreme crush injuries, partial amputations, and open fractures. A mother helped me bandage her infant, whose left hand was gone. It took an hour, but once the baby was bandaged, she was calmer. I can't imagine what the mother is going through. I changed the bandages on a little girl and it took me a while to see the wound, but part of her skull was missing. She needs immediate reconstructive surgery.

A young man, about 23, had a traumatic crush injury. He was looking all right, young and strong, but his leg was dead and had to come off. If you can remove gangrenous limbs, you can save people. But we couldn't, and the next day he died of sepsis. Another woman seemed to be doing well she was talking and I was optimistic to the point of reassuring her family. But within minutes she collapsed. We tried to resuscitate her but she died, maybe from a huge clot. I don't have X-rays, so I don't know. I see tons of stuff in the emergency room in Los Angeles gunshot wounds to the head, car crashes but the injuries here are just so, so terrible. It's like putting your finger in the dike, because for the first day we could only offer first aid like IVs, antibiotics, pain medications and bandages. More wounded come to us everyday, praying and shouting, but it is less chaotic because people have died. I can't begin to express how uplifting it was when our first backup teams arrived on Friday morning. Now we can start to do something more. We have set up some temporary operating theaters. I was working earlier with a surgeon performing some emergency amputations nothing fancy, but lifesaving.

The thing is, after surgery it's not like patients can go home. Many have no homes to go back to. And they will need a lot of follow-up care, wound debridements (the removal of dead or infected tissue), dressing changes, infection and pain control. A lot of amputees and the paralyzed will need lifelong care.

I know it's not easy for amputees anywhere, but Port-au-Prince is not a flat place and getting around is tough. One woman I am caring for is paraplegic. It is going to be really hard on her and her family. They will have to take care of her for the rest of her life. There are countless others in similar situations. I still don't know what happened to a lot of my Haitian colleagues. But more and more show up every day to help. I see them, not sure if they had even survived, and we're crying as they tell me how they lost a brother or sister, a husband, a wife or a child. Then everyone gets to work. Even though it seems like everyone has lost someone, their home, their way of life, it is amazing how people are helping each other. A lot of children have been orphaned. There is one beautiful little boy, who is about four years old. I don't know where he came from or how he got into our makeshift hospital compound, because he doesn't really have any injuries. I asked him if he was alone, and he told me, "Yes, I am alone, but I'm here with my friends." I look around and all of his friends are people he doesn't know, all waiting for surgery. Dr. Cabeza is the medical coordinator with MSF in Haiti. I can't remember what I have done for the past five days.

I have no time to think about what's going on around me. I just do the work that needs to be done. Right after the earthquake, I remember hearing the voice of our guard on the walkie-talkie saying over and over again: "The hospital collapsed! The hospital collapsed!" I tried to get there by car, but it was impossible, so we walked. It was eerily quiet even though everyone was on the streets. The sun set quickly, and when we arrived it was already dark. Trinité Hospital was one of the only trauma care centers in Port-au-Prince, and the people arriving for care panicked somewhat when they saw the hospital was destroyed. We immediately began helping people out of the rubble, treating them on the street all through the night without much light. Two nurses managed to crawl out of the collapsed hospital, shocked and traumatized, and we could hear the voices of others. A Haitian colleague—a gifted doctor—was among those we freed. But he died shortly after being pulled from the wreckage. That hit the team hard. By Friday we thought there was no one left alive, because the voices stopped.

Then we heard a young man talking, and we quickly sent him food through the cracks and water through a tube, waiting for specialized help to free him. On Saturday, a rescue team of Venezuelans, Peruvians and Americans took three hours to dig him out. He was alert and only had minor leg injuries, and hopefully no internal injuries. This small bit of good news gave the team a boost. The number of people in need of surgery is overwhelming. They keep coming by foot, carried in wheelbarrows, or on other people's backs. My colleagues and I have not stopped working, providing as much first aid as we can under tents, while rushing to scale up our surgical capacity.

On Saturday morning, we set up a makeshift operating theater in a shipping container that used to be a pharmacy. The surgical team performed 20 surgeries, several amputations, and even a laparotomy (abdominal surgery). In the neighborhood of Cité Soleil, my colleagues were able to set up two operating theaters at Choscal Hospital, and they are working around the clock with hundreds of patients in need of surgery. Teams are working like this throughout the city in neighborhoods like Martissant, Delmas and Carrefour but we are running out of medical supplies in several facilities, as well as fuel for our refrigerators to keep medicines and vaccines effective. The destruction here is enormous. Almost every school I have seen since last Tuesday has collapsed. The same thing for markets, public structures and homes. The health infrastructure was weak before the earthquake, and neglected by international donors, but no public-health system could have prepared for a disaster like this. Rebuilding this city will take years.
 

Ms. Chouinard is the head of mission with MSF in Haiti.