P81.9Disturbance of temperature regulation of newborn, unspecified

P81.9 is the ICD-10-CM diagnosis code for disturbance of temperature regulation of newborn, unspecified. It belongs to category P81 (other disturbances of temperature regulation of newborn), block P80-P83 (conditions involving the integument and temperature regulation of newborn) and chapter 16 (certain conditions originating in the perinatal period). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

Within P81, choose P81.9 (Disturbance of temperature regulation of newborn, unspecified) only when documentation doesn't support a more specific option: environmental hyperthermia of newborn (P81.0) and other specified disturbances of temperature regulation of newborn (P81.8).

It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.

In MS-DRG v44.0, it is part of the grouping logic for DRG 794 (Neonate with Other Significant Problems, relative weight 1.4935), in MDC 15 (Newborns and Other Neonates with Conditions Originating in the Perinatal Period), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Before ICD-10, this condition was coded in ICD-9-CM as 778.4 (other disturbances of temperature regulation of newborn).