newborn CBCs

[Stitch]

This topic has been long on my mind. How do you guys screen your term neonates for infection/sepsis if there's any question. For example mom is GBS positive and came in late so she didn't get treated. Our neos do a CBC and blood culture. If the I:T ratio is greater than 0.2 (sometimes 0.3 depending on who you ask), the white count is less than 5 or greater than 35, the kid will probably get 48 hours of amp/gent. Same thing if the OB says the word 'chorio.'

What are your cutoffs and how do you approach this situation? I feel a CBC/diff is pretty worthless, but I don't have anything better. One guy is starting to use a CRP too, but I don't think there's much data behind it.

---

Members don't see this ad.

 

[BigRedBeta]

I'm at an institution that does screening H&H's and glucoses on EVERY newborn - even healthy term infants regardless of risk factors or symptoms. I think that's pretty rare (as a medical student somewhere else, I remember indications for blood sugars being a huge deal as part of our newborn nursery week).

For babies with risk factors, we're pretty much where you are. Because we get labs regardless, many of our neos and the general pediatricians who run the term nursery side will wait to get a CBC at 4 hours after delivery to allow the stress response to run it's course though it's attending dependent. I/T ratio cutoff is 0.2 for us, but there aren't any hard fast rules for what the white count has to be, particularly if the I/T ratio is very low. Maternal fever/chorio is definitely a "go" term around here.

There's one nursery attending who is with you on disliking CBC's. A CRP might get him more excited, but he wants to know what the baby is doing/looking like before considering anything else.

I think there's an article out there (or I heard a rumor about one) advocating the use of CRP's, but I think it's a rather small study and probably needs more validation. I don't really feel like looking for it right now.

 

[oldbearprofessor]

I haven't used a CBC (or CRP, etc) in the first 12 hours of life to decide on treating a baby with antibiotics in over 20 years. After 12-24 hours, these start to become mildly useful in the NICU setting.

The Red Book covers 90% of situations. Common sense covers the other 10%. Chorio always gets treated. Overtreatment of healthy full-term infants with antibiotics is not benign.

Fortunately, I don't often get in a situation in which I have to make these decisions since I'm in the Level 4 NICU setting almost always. This is good for me as these situations would not be good for my blood pressure. Give me a baby with HMD needing intubation over a two hour debate on antibiotics on a healthy baby whose mom had a temp of 101.3983 degrees at 74 minutes before delivery any day.

 

[rotatores]

I haven't used a CBC (or CRP, etc) in the first 12 hours of life to decide on treating a baby with antibiotics in over 20 years. After 12-24 hours, these start to become mildly useful in the NICU setting.

The Red Book covers 90% of situations. Common sense covers the other 10%. Chorio always gets treated. Overtreatment of healthy full-term infants with antibiotics is not benign.

Fortunately, I don't often get in a situation in which I have to make these decisions since I'm in the Level 4 NICU setting almost always. This is good for me as these situations would not be good for my blood pressure. Give me a baby with HMD needing intubation over a two hour debate on antibiotics on a healthy baby whose mom had a temp of 101.3983 degrees at 74 minutes before delivery any day.

if only there were guidelines for this...

I agree OBP...I think the initial CBC is rather useless...which is why one has to further look at both the CRP and I:T ratio, preferably at the 12-18 hour mark.

Chorio...even if only muttered by the OB = workup/Abx....the real question is to tap or not. I don't...but know some docs who will.

 

[Stitch]

if only there were guidelines for this...

I agree OBP...I think the initial CBC is rather useless...which is why one has to further look at both the CRP and I:T ratio, preferably at the 12-18 hour mark.

Chorio...even if only muttered by the OB = workup/Abx....the real question is to tap or not. I don't...but know some docs who will.

Yeah, I tend not to tap unless I'm worried about HSV or something like that.

We've talked about using CRP. Any data on that? I generally just use the I:T ratio (which I am also skeptical about)

 

[CrazyPeds527]

I remember hearing that the 24hr CRP if > 2 has a higher PPV for active infection, but dont remember the specifics of the data.

We also use the CBC and I:T of > 0.2, however if the newborn has even a borderline I:T, we seem to use other factors (mom's GBS status, what does the baby look like, why was the CBC done in the first place) to determine treatment or not.

Also, the ever popular "attending dependent" decision seems to factor in

Agree, though, if "chorio" the baby gets transferred and worked up

 

[antihero94]

WE have a specific algorithm.

Maternal temperature> 101 --> automatic antibiotics


Maternal GBS Positive +
Temperature 100-101 --> CBC and treat if I/T > 0.2, or WBC < 5000
Intact membranes or completely treated without fever --> supportive care


Maternal GBS Negative
Any of the following risk factors?
- Maternal chorio
- Prolonged rupture of membranes (>24 hours)
- Fetal tachycardia (sustained HR > 160)
- < 37 weeks gestation
Then: CBC and treat if I/T > 0.2 or WBC < 5000


Maternal GBS Unknown
If fully treated --> treat as GBS negative
If not fully treated and any of the risk factors listed above --> CBC

The catch is that one of the hospitals we staff the delivery room and NICU at now has a "rule out chorio" protocol for women with any temp over 100.4. Therefore, our hands have been tied and we are really treating anyone with a maternal temp.

 

[KidDr]

WE have a specific algorithm.

Maternal temperature> 101 --> automatic antibiotics


Maternal GBS Positive +
Temperature 100-101 --> CBC and treat if I/T > 0.2, or WBC < 5000
Intact membranes or completely treated without fever --> supportive care


Maternal GBS Negative
Any of the following risk factors?
- Maternal chorio
- Prolonged rupture of membranes (>24 hours)
- Fetal tachycardia (sustained HR > 160)
- < 37 weeks gestation
Then: CBC and treat if I/T > 0.2 or WBC < 5000


Maternal GBS Unknown
If fully treated --> treat as GBS negative
If not fully treated and any of the risk factors listed above --> CBC

The catch is that one of the hospitals we staff the delivery room and NICU at now has a "rule out chorio" protocol for women with any temp over 100.4. Therefore, our hands have been tied and we are really treating anyone with a maternal temp.

When you say "treat", do you mean blood culture and 48 hour rule out? Or more than that?

 

[antihero94]

When you say "treat", do you mean blood culture and 48 hour rule out? Or more than that?

Yeah, treat is blood culture, amp/gent X 48 hours regardless of CBC. If CBC is not reassuring, many attending will often also do an LP, but not necessarily prior to antibiotics, just looking for pleocytosis and evidence of meningitis.