Ellen de Kort

82 Chapter 5 Another scoring system is the relaxation score also used in the report of Smits et al., combining this score with the abovementioned sedation score. After the administration of propofol, level of sedation andmuscle relaxationwere determined. For relaxation, themuscle tone of the extremities was assessed (1 = hypertonic, 2 = normal tone, 3 = mildly hypotonic, 4 = hypotonic). Also, scores 3 and 4 reflect adequate relaxation. Both sedation and relaxation were assessed by the intubating neonatologist. Additional propofol was administered if sedation and relaxationwere found unsatisfactory, until a satisfactoryconditionwas achieved with no predefined maximum dose of propofol. 13 In the report of De Kort et al., in case of ineffective sedation, additional remifentanil was administered up to a predefined maximum, with a conversion to propofol in case of persisting inadequate sedation. 14 The third score is from Thall et al., in their report describing how to perform dose- finding studies for premedication in neonatal intubation. 16 For this purpose they used the Neonatal Pain, Agitation and Sedation Scale (N-PASS) first described by Hummel et al. 30 The score consists of 5 variables that should all be scored within 5 minutes of the first sedative administration: crying/irritability, behavior state, facial expression, extremity tone, and vital parameters. Each item is scored on a 5-point scale from -2 to +2, with -2 corresponding to highest sedation and +2 corresponding to highest infant discomfort. For the purpose of endotracheal intubation, Thall et al. considered a score between -7 and -3 to reflect a good sedative state. 16 DISCUSSION This systematic reviewwas performed to provide insight into the availability of validated objective scoring systems to assess newborn infants’ level of sedation prior to intubation. The literature as per January 27, 2017 does not provide such a validated scoring system. The decision to proceed with the intubation procedure after administering premedication should be based on the pre-intubation sedation level. However, studies reporting on this issue show that level of sedation is not always the key factor to proceed with intubation. In several studies, intubationwas proceededwhen a certain period of time had elapsed after the administration of premedication, assuming this amount of time being sufficient for drug effect. However, as drug pharmacokinetics and pharmacodynamics can differ considerably depending on gestational age and postnatal age, sufficient drug effect may need a different period of time in individual patients. Using the same time frame in all neonates may very well lead to a proportion of patients not being adequately sedated for the procedure. To guide individualized dosing, we strongly recommend basing the start of the intubation on the actual level of sedation and administering extra doses if necessary.