Subject matter of the present invention is an in vitro method for identifying a subject in need of administration of fluid resuscitation or a vasopressor comprising the following steps: Determining the level of proADM and/or fragments thereof having at least 6 amino acids in a bodily fluid of said subject Correlating said level with the need of said patient for fluid resuscitation or administration of a vasopressor wherein said patient is identified as having such a need if the level of proADM and/or fragments thereof having at least 6 amino acids in the bodily fluid of said subject is above a threshold.