First, let me say how sad we all feel when a baby dies. In my experience both
as an OB nurse and an LC I have witnessed my share. Tragic feelings of
helplessness come over us when we feel that we might have helped.
In this case, Susan, the dehydration appears to have occured rapidly as a
result of the vomiting and diarrhea. I agree that for this infant it was a
combination of factors.  My first guess is an inborn error in metabolism of
some type. The pedilyte and formula may have exacerbated the situation, but
breastfeeding may not have saved the infant either. This mother DID
EVERYTHING she could, did everything she was told to do.

A  Peds endrocrinologist taught me to look at the color and consistancy of an
infant's stool as a part of a normal exam. Green streaks, foam, mucous and
other matter in an infant's stool can be diagnostic. The only way to learn
(because there isn't a color illustrated book on the subject) is to look at
stool, from every baby you see. Abnormal stools may be the only clue to some
disorders regardless of weither the infant appears to be thriving. (I'd like
some MD input on this one) When the stool remains unusual coupled with fussy
or lethargic behaviors, the most we as LCs can do is *push* the parents to
keep going back to the physician, camp out in the ER or the office if need
be, and suggest another medical opinion.

A particular case of mine comes to mind. The baby's only initial symptoms
were prolonged jaudice and foamy, slimely, dark  green stools. The physician
said it was breastmilk jaundice (no lab studies were done) and told mom not
to worry. The parents were VERY anti-medicine, home delivery, no
immunizations,  etc... and accepted the physician's diagnosis without
question.  (This was mom's second baby and her first had breastmilk jaundice)
 At 6 wks the baby's bili was still up in the 20's and the weight gain was
slow. The physician continued to assert that it was breastmilk jaundice and
it would pass if she would only stop breastfeeding. At 8 wks mom called and
said the baby looked like he was shrinking. The parent's refused to take the
infant to the hospital, they wanted to see me instead. When they arrived at
my office, I was horrified at the condition of the infant. He was literally
forrest green and emaciated. He looked like a limp rag and was unresponsive.
Fortunately, I was working in a physician's office at the time, and she took
over immediately. The doctor argued with the parents for what seemed like
forever. Finally she said "If you won't do something now, I will,"  picked
the baby up and rushed him to the hospital herself. The baby had a full
arrest as they walked in the door. Once he was fairly stable he was
transferred to a major children's hospital, where he would go into cardiac
arrest 2-3 times a day. After weeks of testing, the physicians diagnosed a
RARE inborn error in metabolism that is considered incompatiable with life.
The infant was unable to buffer acids, and suffered from constant metabolic
acidosis. For a while they were able to compensate with medication. He was
fed breastmilk through a gastrostomy tube for the rest of his short life. He
died at home, in his mother's arms, just 2 days shy of his first birthday.
 I could barely speak when she came to return the pump and handed me a
picture of her little one and myself that was taken when he was 3 days old.
I have never felt so helpless or hopeless in my life.