Dexmedetomidine for Analgosedation to Newborn Infants During Neonatal Intensive Care

Inclusion Criteria: * Newborn infants: - born 34+0 gw with a need for dexmedetomidine for analgesic and/or sedative treatment after postnatal surgical correction of congenital malformations and who will be cared for in the PICU (postoperative intensive care unit) and in a some few cases in the NICU (neonatal intensive care unit), or * with a corresponding age of 37 gw, who are in need for dexmedetomidine according to clinical judgment and cared for in the NICU. * Existing arterial or venous cannulas/catheters for repeated nontraumatic blood sampling * Informed and written parental consent obtained before study start. Exclusion Criteria: * Infant older than age corresponding to gw 46+0 * Previous treatment with the dexmedetomidine within 72 hours (only for postoperative infants). * Congenital cardiac malformations requiring surgery on extracorporeal circulation and treatment with hypothermia. * Ongoing renal replacement treatment * Any serious medical condition or ethical issues that could, in the investigators opinion, interfere with the study procedures.