Impact of hypoxaemia on neuroendocrine function and catecholamine secretion in chronic obstructive pulmonary disease (COPD). Effects of long-term oxygen treatment

AbstractThe aim of the study was to investigate the effects of chronic hypoxaemia on neuroendocrine function in hypoxaemic chronic obstructive pulmonary disease (COPD). The stress level was assessed by measurement of daytime plasma catecholamine and nocturnal urinary catecholamine levels and endocrine function was assessed by measuring serum gonadotropins, peripheral sex hormones and peripheral thyroid hormones, and by measuring thyroid stimulating hormone (TSH), prolactin and growth hormone before and after thyroid releasing hormone challenge in 12 male, stable, hypoxaemic COPD patients before and after at least 4 months of long-term oxygen treatment (LTOT). Mean pre-treatment P aO2was 7·39±0·78 kPa and mean nocturnal arterial oxygen saturation (MSaO2) was 86·6±3·2%. Plasma norepinephrine (NE) levels were higher than normal, while all other pre-treatment hormone levels were within normal range. Low forced expiratory volume in 1sec (FEV1) was associated with low basal and stimulated TSH (P<0·01). Urinary NE excretion correlated positively to nocturnal time spent with SaO2<85% (P<0·05). In similarity with normal controls, positive correlations were found between sex hormone binding globulin and testosterone both before and after LTOT (P<0·01). No significant hormonal changes were noted following an average of 8 months of LTOT for the entire study group. However, in a subgroup (n=6) with an increase in MSaO2exceeding 7% points following LTOT, nocturnal excretion of NE and epinephrine were reduced by 30% (P<0·05) and S-free thyroxin by 20% (P<0·05).In conclusion, patients with chronic hypoxaemia secondary to COPD exhibit elevated plasma NE levels but otherwise normal endocrine levels, including a normal hypothalamic–pituitary–testicular axis. The severity of airway obstruction is associated with reduced basal and stimulated TSH. The endocrine function is not significantly changed following LTOT except for a subgroup with severe nocturnal hypoxaemia, where elevated nocturnal NE excretion was noted, which was reduced only if whole night oxygenation was normalized during oxygen therapy

Management and Outcome of Febrile Infants ≤60 days, With Emphasis on Infants ≤21 Days Old, in Swedish Pediatric Emergency Departments

BACKGROUND: Management of febrile infants ≤60 days of age varies, and the age for routine investigations and antibiotic-treatment is debated. The American Academy of Pediatrics recommended age threshold for lumbar puncture (LP) is 21 days and for blood culture 60 days. We describe management and adverse outcome of febrile infants ≤60 days old, in Sweden.METHODS: Retrospective cross-sectional study of infants ≤60 days of age with fever without source evaluated in 4 University pediatric emergency departments, between 2014 and 2017. Adverse outcome was defined as delayed-treated invasive bacterial infection (IBI: meningitis or bacteremia).RESULTS: We included 1701 infants. In infants ≤21 days old, LP was performed in 16% (95% CI: 12-20) and blood culture in 43% (95% CI: 38-48). Meningitis was diagnosed in 5 (1.3%; 95% CI: 0.4-3.0) and bacteremia in 12 (4.5%; 95% CI: 2.6-7.0) infants. Broad-spectrum antibiotics were not administered to 66% (95% CI: 61-71), of which 2 (0.8%; 95% CI: 0.1-2.8) diagnosed with IBI (1 meningitis and 1 bacteremia). In the 29-60 days age group, blood culture was performed in 21% (95% CI: 19-24), and broad-spectrum antibiotics were not administered to 84% (95% CI: 82-86), with no case of delayed-treated bacteremia.CONCLUSIONS: The rates of LP, blood culture and broad-spectrum antibiotics were low. Despite that, there were few delayed-treated IBIs, but 2 of the 17 infants ≤21 days of age with IBI were not timely treated, which prompts the need for a safer approach for this age group. Also, the utility of routine blood culture for all febrile infants 29-60 days old could be questioned