Pediatric Cardiology and Cardiac Surgery
Vol.26 No.5 2010 (407-412)
Yoshiho Hatai,1) Tadahiro Yoshikawa,2) and Shin Amamiya 3)
1)Sakakibara Heart Institute Clinic, Shinjuku, Tokyo, 2)Sakakibara Heart Institute, Fuchu, 3)Saitama Medical University, Iruma, Japan
Abstract
Background: Hypoxia inhalation therapy is clinically used for the treatment of patients with congenital heart disease; however, there is no report related to hypoxia inhalation therapy in neonate and infant and subsequent possible occurrence of mental or neurological disturbance.
Methods: To investigate the possible adverse influence of hypoxia inhalation therapy on the central nervous system, we evaluated 5 neonates of age of 6 days to 19 days (mean 10 days) during the therapy and 23 patients from 4 months to 36 months (mean 15 months) thereafter at follow-up. In the acute period, we measured the change of vital signs, arterial blood gas and regional cerebral oxygen saturation during therapy with oxygen content ranging from 15 to 21%. Electroencephalography (EEG) and brain computed tomography (CT) or magnetic resonance image (MRI) were evaluated. During follow-up, we examined the patients’ physical growth including body weight, Kaup index and head circumference (Kaput index=weight (g) / (height (cm) × height (cm) × 10). Neurological abnormalities and development of convulsion were checked by physical examination and medical history from their parents. Mental development was assessed with the Tsumori-Inage infant development scale.
Results: In the five neonates, the heart rate was decreased from 141±13 to 137±15 min-1 and mean blood pressure was increased from 44±9.2 to 47±11.5 mmHg. Arterial oxygen tension was decreased from 67±19.3 to 48±15.8 mmHg. Regional cerebral oxygen saturation was increased with 18–20% oxygen inhalation, but decreased with further hypoxia less than 16% oxygen. EEG did not change even with the administration of 13–14% oxygen. Neither brain CT nor MRI showed cerebral bleeding or infarction. At follow-up, physical growth was not retarded (mean body weight; -0.98 standard deviation (SD), mean Kaup index; 16.6, mean head circumference; -0.77 SD). Two patients were hypotonic and one patient had a transient convulsion. There was no significant difference in the Developmental Quotient between therapy and control group (94±26 versus 98±24, p=0.70).
Conclusion: This study suggests that hypoxia inhalation therapy may be clinically useful without adverse neuro-developmental outcomes for the patients with congenital heart disease.