October 13, 2008

Dealing With Fussy Neonatal Codes
By Judy Sturgeon, CCS
For The Record
Vol. 20 No. 21 P. 6

In the world of inpatient ICD-9-CM coding, it would seem simple enough to assign the correct code for respiratory distress syndrome (RDS, or hyaline membrane disease) in a newborn. The code itself is certainly no challenge—how many three-digit codes are still in existence? Even a novice can commit “769” to memory. The diagnosis-related group (DRG) that the code generates has changed number labels since the activation of Medicare severity DRGs, but the text still reads the same: Extreme immaturity or respiratory distress syndrome, neonate.

Whether the infant was born at the treating facility or transferred from elsewhere, there are still basic criteria to be met in order to use code 769. The physician must specifically document the diagnosis, and it must affect patient care in some way. A review of the patient’s chart will nearly always validate respiratory symptoms, oxygen supplementation, lab tests, radiology, and possibly even surfactant administration. So, how can this particular disease be a problem for coders?

Let’s start with the problem it presents to third-party payers that process reimbursement by the DRG method. In many cases, there is no question regarding the diagnosis, authorization for admission on transfers, or DRG validation by managed care staff or postdischarge auditors. These babies are also frequently extremely premature with birth weights under 1,000 grams. In those cases, either the extreme prematurity or the RDS will validate the DRG.

However, what about cases in which there are relatively short stays—a few days to a week or two—and documentation of the additional modifier mild respiratory distress syndrome or mild hyaline membrane disease? Faced with an expected bill in the neighborhood of $75,000 in contrast to approximately $21,000 in the lesser DRGs of prematurity with major problems or a mere $4,000-ish ticket for preterms with no significant problems, the payer can be expected to balk unless documentation clinically supports the diagnosis in question.

This is a significant compliance concern. The inpatient coder must have a comprehensive understanding of the pathophysiology and be able to identify supporting documentation, as well as ambiguous or conflicting documentation regarding RDS/transient tachypnea of the newborn (TTN). While it would be much simpler were it permissible to “just code it when they say it,” professional ethics require the coder to do more than just look up a code and stick it on a claim. The Centers for Medicare & Medicaid Services always directs the coder to query the physician for clarification when there is any doubt.

This isn’t a new problem. The American Hospital Association’s Coding Clinic from November-December 1986 initially separated RDS into type 1 (coded to 769) and type 2 or TTN (code 770.6). It further stated that the type 2 version was also referred to as mild and commented that recovery was generally made by the third day of life.

Confusion continued, however, and the first quarter 1989 issue of Coding Clinic added that the two conditions were mutually exclusive: The coder was allowed to apply only one of the diagnoses. The explanation continued that the tabular instructions with each code excluded the other, and RDS includes clinical symptoms of tachypnea. It further added that the milder diagnosis of TTN “by definition resolves within 6 to 24 hours of birth.”

So, what about the baby with documented mild hyaline membrane disease or mild RDS? The index to ICD-9 does not include the term mild as either a nonessential modifier or any type of modifier at all. A few years ago, it dropped the terms type 1 and type 2 altogether for being confusing and no longer in common usage. Auditors for the payer are inclined to use the existence of the adjective mild to reject the more severe diagnosis of RDS, regardless of the length of its existence and treatment modality.

Even physicians themselves have trouble reaching a consensus about when the problem constitutes RDS and when the symptoms are representative of the less severe diagnosis of TTN. Some neonatologists may use the terms TTN and mild RDS interchangeably. Others may be specific about which diagnosis should be expected to manifest the increasing severity of symptoms and are careful about their terminology and supporting documentation. If neither the payers nor the doctors can agree on what constitutes a valid RDS diagnosis, how are coders supposed to figure it out?

At least in this instance, it is reassuring to be able to fall back on the oft-maligned directive to query the physician for further clarification. If the documentation always says TTN and there is no clinically significant chest x-ray and the baby recovers in two or three days without oxygen or with a face mask for only a few hours, there should be no problem with clinical support for a TTN code assignment.

If the baby is extremely preterm, has a chest x-ray that shows haziness consistent with surfactant deficiency, receives surfactant administration, is ventilated mechanically or supported by continuous positive airway pressure (CPAP) or high-flow nasal cannula (HFNC) for more than 24 hours, and the doctors refer to the problem only as hyaline membrane disease or RDS, the code of 769 and its generous DRG should be well supported.

But when the chart says mild RDS or mild hyaline membrane disease, there are some useful basic qualifiers to help the coder determine whether code 769 is clinically supported or whether the query form needs to be utilized prior to finalizing coding and DRG assignment.

If the physician uses both TTN and RDS in the baby’s chart without clearly explaining at discharge which is correct and why, query the physician. Don’t try to guess—too much money and too much compliance risk is involved for the coder to make this decision.

If the chest x-ray is consistent with surfactant deficiency, and the doctor does not use the term TTN, and the baby receives surfactant administration or is on a ventilator, CPAP, or HFNC oxygen support for at least 24 hours, code 769 is clinically supported. On the other hand, if this same baby has its diagnosis referred to only as TTN, the coder needs to go back to the physician for clarification because the clinical picture is significantly more severe than is usual for transient tachypnea alone.

If the chart reads RDS but the chest x-ray shows no surfactant deficiency, or if the baby is not on at least 24 hours of oxygen therapy, the coder needs to query the physician for clarification. Even with a clinically significant chest x-ray but minimal oxygen support, the true diagnosis is more likely to be TTN rather than RDS. Break out the query form and go back to the physician for verification.

Because the length of stay is often extended by prematurity or other secondary diagnoses, that alone is not sufficient to validate RDS over TTN. And as onerous as it can be to have to politely ask the doctors to clarify which diagnosis is most appropriate, it is nowhere near as unpleasant as receiving a negative audit and a visit from the state or the Office of Inspector General.

Help may be on the way. Coding Clinic hopes to refer this issue to its editorial advisory board for review when it meets next month. In the interim, remember that the responsibility for clearing up the newborn’s lungs and the correct diagnosis for the problem is the responsibility of the physician, not the coder.

— Judy Sturgeon, CCS, is the hospital coding senior manager at The University of Texas Medical Branch in Galveston and a contributing editor at For The Record. While her initial education was in medical technology, she has been in hospital coding and appeal management for nearly 20 years.