Certainly. Warning--this is long!!!
DS had a severe congenital heart defect called tetralogy of fallot which was dx hours after birth, spent 2.5 weeks in NICU, had one surgery, came home at about 3 weeks old. About a week after he came home he decided he would not be put down, would not sleep in the cosleeper, would only sleep on our chests (or perhaps next to me in bed). He had a heart shunt that could close if he got dehydrated, so we had to wake him up to eat at least every three hours (combo of BF and formula, my milk supply was minimal). I think he might have started sleeping longer stretches around 2-3 months but we had to keep waking him up. Then he had another surgery at 3 months, an emergency, and it was rough. He was in the hospital for a week, and you know they poke them and take blood pressure every 20 minutes so that added to the trauma of surgery just messed him up. I held him most of the time he was in recovery, including all night long in the little chair they gave me next to his bed b/c he just screamed if I put him in the crib. The stupid nurse kept telling me to put him down because he "needed his rest" but he wasn't exactly "resting" when I did put him down since he had never slept in a crib!
When we got home he wouldn't sleep for more than 20 minutes at a time, even during the day. He'd sleep for 20 minutes, be awake and cranky for 20 minutes, then I'd spend the next hour trying to get him back to sleep. He woke up screaming (I held him almost 24 hours a day during his first 6 months or so) and sometimes had night terrors (where he didn't really wake up but got rigid and screamed for half an hour). He woke up regularly every half hour or so for months. Until he was about 6 or 7 months old he would just latch on and go back to sleep. But after that he needed to be carried around to get back to sleep. It was killing me. I went back to work part time when he was about 9 months and daycare was horrible for him, he wouldn't be put down and wouldn't sleep there. So I quit my job at about 11 months. After he learned to sit up around 6 months the separation anxiety got a little better, I could sit with him on the floor while he played for a few minutes, and then when he crawled it got even better, he would play in the same room for a few minutes. But naps were awful--he took 3-4 20-30 minute naps a day, and nothing I did to extend them worked. Sometimes he would sleep a whole hour, and he was so much happier on those days. He was so cranky and miserable all the time, and I had no idea how much this was due to his sleep.
When he was 11 months old we changed some things. I was dying, I screamed at him all the time, I ran red lights in the car. DH had been sleeping on the spare futon most nights, and taking DS in the chair on the nights when I just couldn't do any more. So we put our spare queen sized futon on the floor in DS's room and started taking turns sleeping with him there. My milk had pretty much dried up by this point (another long story) so the partial night weaning wasn't a big deal. It was tough for DH to get DS to sleep with him lying down, as he wanted to be held. It took several weeks I think of walking around then lying down, sleeping on DH's arm, etc. But it was magnificent. I got a full night's sleep every other night. DS still woke up just as often with his dad but we were more capable of dealing with him.
After he turned 1 a lot of things changed. He started eating solid food finally. He got a little more mellow, more able to handle things. And he started sleeping better. I think it was the partial night weaning, maturity, and, finally, I stopped nursing him to sleep on the nights I put him to bed. I did this cold turkey--but we had developed a bedtime routine before this. We moved his bedtime from 8:00 to 6:30 (slowly). We realized that he spent the time between dinner and bedtime getting completely maniacal and what was the point of that? It was winter, and the sun set early, so this wasn't as big of a change as I thought it might be. We had dinner, bath, story, tooth brushing, then into his room with a bottle. Pitch black room, I mean, so dark you couldn't see your hand in front of your face. I would hold him on my lap while he had his bottle (formula until 14 months, then milk) and then we would lie down together. For the first couple weeks, he would cry when I wouldn't let him nurse. I would hold him, and carry him around. Then lie down again. After a while, he would just fuss a little like he was annoyed with me and then he'd roll around for a while, crawl around the bed, babble nonstop, bang on the dresser, open and close the closet door, you get the idea. After about half an hour he'd come and lie beside me and get quiet, and finally just go to sleep.
He started sleeping longer stretches after we did this. He'd sleep 2 hours, then 3, and now he usually goes 4-5 unless he's having a bad night. Also, he will sleep alone for a couple hours after he goes to bed. Heaven!!! DH and I hadn't had 5 minutes alone since he came home from the hospital.
Anyway, I have no idea if something we did really helped him, or he just needed time to mature, but I think it was a combination of both. I think he would have been super high needs anyway, but his medical traumas just added extra to it and made it unbearable. BTW he's almost 18 months now, getting more independent and is generally happy, if intense and full of energy
He usually takes one 2-3 hour nap per day now, half in his bed and half on my chest in the sling. I never would have thought it possible, after a year of 20 minute naps!!
I have written a lot about DS's surgeries etc. on his website if anyone is interested http://schnoogly.com/pages/iainspage.htm