[Cortisol concentration, hypotension and treatment of cardiovascular insufficiency in the first days of life of very preterm newborns - preliminary report].
Hypotension is a serious condition occurring in extremely premature newborns. One of the treatment methods is administration of hydrocortisone. Preliminary study results indicate that this treatment is effective, but it also bears the risk of complications which may result from cortisol level in the bloodstream prior to the treatment. The aim of the study was to find a correlation between blood cortisol concentration levels of extremely premature newborns, their gestational age and the incidence of hypotension. If hydrocorisone administration was required, safety of its use was evaluated.


METHODS
The study included 35 preterm newborns (< or = 330 weeks of gestation) admitted to the Neonatal Intensive Care Unit (NICU) at the Institute of Mother and Child in the first 72 hours of life during the period between 01.01.2006 and 30.12.2007. Their mean gestational age was 26.2 weeks of gestation (23-30) and the mean weight was 860.3 g (500-1500 g). Exclusion criteria were congenital abnormalities and heart disease with the exclusion of PDA and PFO, as well as cortisol level >1400 nmol/l for the newborns treated with hydrocortisone. Initial serum cortisol level was measured in the umbilical blood or immediately after admission to the NICU. Cortisol level was determined by LIA method using Liason apparatus, and the results were presented in nmol/l. If hypotension was diagnosed (mean arterial blood pressure value <10 percentile for gestational age in mmHg), 0.9% NaCl was used and catecholamines (dopamine and dobutrex)were administered. If the hypotension was not responding to treatment hydrocortisone was administered. During hospitalization echocardiography and cranial ultrasound examinations were performed, assessing main complications: IVH, PVL, SIP, NEC and hyperglycemia (blood glucose concentration >200 mg%). STATISTIC ANALYSIS: Calculations were made with the SPSS v 12.01 statistical software. Chi(2) test, Mann-Whitney and Spearman tests were used. Significance level of alpha <0.05 was applied.


RESULTS
A wide dispersion of serum cortisol levels was observed (58.5-3766.5 nmol/l: median - 293.8 nmol/l) and no correlation was found between the gestational age and cortisol level and the incidence of hypotension. Ten infants required hydrocortisone administration (29%). In the tested group intestine perforation was diagnosed in 6 infants (17%). In both groups hyperglycaemia was found in 50% cases. No case of PVL was diagnosed in the studied group. Statistically significant difference was noted regarding IVH grade III and IV. Their incidence was higher in the group with hypotension (48%) as compared to the non treated group (10%).


CONCLUSIONS
1. The dispersion of serum cortisol levels in the first 72 hours in very preterm newborns is wide. No correlation was found between cortisol level and gestational age and the incidence of hypotension in the studied population. 2. In hydrocortisone-treated group no complications such as SIP and PVL were found. The incidence of hyperglycemia was the same as in the untreated group, which may indicate that the treatment is safe. The results need to be confirmed on a larger number of patients. 3. It was confirmed that hypotension is a significant risk factor for IVH. 4. The study needs to be continued in order to increase the population of newborns treated with hydrocortisone. Their long term follow-up will make it possible to assess the safety of this treatment.
Rutkowska
Magdalena
M
Klinika Neonatologii i Intensywnej Terapii Noworodka, Instytut Matki i Dziecka, 01-211 Warszawa. magda_rutkowska@poczta.onet.pl
Resko-Zachara
Marzena
M
Adamska
Ewa
E
Ołtarzewski
Mariusz
M
Szamotulska
Katarzyna
K
D002561:Cerebrovascular Disorders / Q000097:blood / Q000175:diagnosis / Q000453:epidemiology* / Q000628:therapy*; D015897:Comorbidity; D004760:Enterocolitis / Q000453:epidemiology; D005260:Female; D005865:Gestational Age; D006801:Humans; D006854:Hydrocortisone / Q000097:blood* / Q000627:therapeutic use; D006943:Hyperglycemia / Q000453:epidemiology; D006973:Hypertension / Q000453:epidemiology; D007022:Hypotension / Q000188:drug therapy / Q000453:epidemiology*; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D007235:Infant, Premature, Diseases / Q000097:blood / Q000175:diagnosis / Q000453:epidemiology* / Q000628:therapy*; D008297:Male; D011044:Poland / Q000453:epidemiology; D012307:Risk Factors; D015996:Survival Rate
D006854:Hydrocortisone