K. L. Cheung

Delivery of salbutamol to nonventilated preterm infants by metered-dose inhaler, jet nebulizer, and ultrasonic nebulizer

To identify the most efficient device for the delivery of bronchodilator aerosol to nonventilated preterm infants with chronic lung disease, we compared the metered dose inhaler (MDI) used in conjunction with a non-valved spacer, an ultrasonic nebulizer with a small medication cup, and two jet nebulizers. The subjects were enrolled in two double-blind randomized crossover studies. In study A (n=10), each infant was given a nominal dose of 200 microg of salbutamol by a MDI (Ventolin) at 4 h intervals, and in random sequence via an Aerochamber (Neonatal Aerochamber) with its one-way valve removed, an ultrasonic nebulizer with a small cone-shaped medication cup (Siemens Electronics), and a jet nebulizer (Side-stream). Their functional residual capacity (FRC) and static respiratory system mechanics were measured before, and at 15, 30, 60, and 120 min after aerosol delivery. Study B (n=10) was carried out in an identical manner, but with a different jet nebulizer (Hudson). In both studies, administration of salbutamol aerosol via the MDI Aerochamber or ultrasonic nebulizer resulted in a significantly greater reduction in respiratory system resistance than via jet nebulizers. Furthermore, the use of MDI Aerochamber or ultrasonic nebulizer was associated with a greater degree of post-treatment tachycardia and improvement in FRC. The bronchodilating effect of salbutamol delivered via the ultrasonic nebulizer appeared to be slightly greater than that via the MDI-Aerochamber, receiving significance only in Study B. We conclude that both the metered-dose inhaler used with a nonvalved Aerochamber and the ultrasonic nebulizer with a small medication cup are both more efficient than the jet nebulizers in preterm infants.

Early onset of hypernatraemic dehydration and fever in exclusively breast-fed infants.

Abstract: Five cases of moderately severe hypernatraemic dehydration were identified within a 5‐month period between two regional hospitals in Hong Kong. Unlike previous reported cases, these exclusively breast‐fed infants presented with the unusual triad of fever, absence of overt signs of dehydration and within the first week of life. Three of the cases also had high serum bilirubin concentrations at presentation. The fever subsided quickly and the serum bilirubin concentration fell rapidly within a few hours of rehydration. All infants made an uneventful recovery without permanent neurological sequelae. Fever, presumably secondary to dehydration, is an useful early warning sign. These cases emphasize the importance of early and regular measurement of bodyweight in exclusively breast‐fed infants so that prompt identification of affected cases may prevent potentially detrimental complications.

Erythromycin treatment for gastrointestinal dysmotility in preterm infants

To report our clinical experience on the use of oral erythromycin for the treatment of severe gastrointestinal dysmotility in preterm infants.

Manganese intake and cholestatic jaundice in neonates receiving parenteral nutrition: A randomized controlled study

Infants requiring parenteral nutrition (n= 244) were randomized to receive either 1 (group 1, n= 121) or 0.0182 μmol/kg/d (group 2, n= 123) of manganese supplementation. The whole‐blood manganese and serum direct bilirubin concentrations of the infants were monitored, as was the development of cholestasis (peak serum direct bilirubin concentration >50 μmol/L). Subgroup analysis was carried out on the data of 78 infants in group 1 and 82 in group 2 who had received manganese supplementation and more than three‐quarters of their total daily fluid as parenteral nutrition for >14 d. Of all the infants randomized, the high manganese group (group 1) showed a trend towards developing higher peak whole‐blood manganese concentration [group 1 versus group 2: median (interquartile range): 606.0 (421.0; 1005.0) vs 566.0 (336.0; 858.0); p= 0.061] and higher peak serum direct bilirubin concentration [37.0 (10.5; 122.5) vs 19.0 (8.0; 112.5); p= 0.153], but the differences between the 2 groups did not reach statistical significance. The 2 groups did not differ in terms of the occurrence of cholestasis during parenteral nutrition (63/121 vs 57/123; p= 0.444). Subgroup analysis of infants who had received more than three‐quarters of their total daily fluid as parenteral nutrition showed, however, that the high manganese group developed significantly higher whole‐blood manganese concentration [743.5 (498.0; 1211.0) vs 587.0 (438.0; 982.0); p= 0.037] and serum direct bilirubin concentration [84.0 (28.0; 170.0) vs 25.5 (9.0; 117.0); p < 0.001]. Although there was no significant difference in the occurrence of cholestasis (58/78 vs 49/82; p= 0.073), more infants in the high manganese group developed a more severe degree of direct hyperbilirubinaemia, with peak serum direct bilirubin >100 μmol/L (32/78 vs 20/82; p= 0.038).

Randomised controlled trial: comparison of colloid or crystalloid for partial exchange transfusion for treatment of neonatal polycythaemia.

AIM To compare the efficacy of using isotonic saline (crystalloid) or 5% albumin (colloid) as replacement fluid in partial exchange transfusion (PET) for the treatment of neonatal polycythaemia. METHODS One hundred and two polycythaemic full term infants were randomly allocated to receive PET with either isotonic saline or 5% albumin. The criteria for PET were: (a) venous haematocrit ⩾ 0.7; or (b) venous haematocrit 0.65-0.69 with symptoms or signs attributable to polycythaemia. RESULTS PET with either saline (n=53) or 5% albumin (n=50) resulted in a significant and sustained decline in haematocrit up to 24 hours after PET. Although the immediate haemodilution effect of isotonic saline was statistically smaller than that of 5% albumin (decline in haematocrit 19.3% vs22.8% of pre-PET value), the difference was too small to be of any clinical significance, and the haematocrit at 4 or 24 hours after PET did not differ significantly between the two groups. PET with either replacement fluid was not associated with any complication. The serum sodium and potassium concentrations were not significantly affected by the PET in either group. CONCLUSIONS Both isotonic saline and 5% albumin are effective when used as replacement fluid in PET for the treatment of neonatal polycythaemia. Isotonic saline, which is cheaper and free of infection, should be the replacement fluid of choice.

Changes in markers of bone metabolism during dexamethasone treatment for chronic lung disease in preterm infants

Aim: To characterise the change in serum and urinary bone markers in the early postnatal period, and to assess the effect of systemic corticosteroid on bone metabolism in preterm infants. Methods: Bone formation was quantified by measurement of serum concentrations of bone specific alkaline phosphatase (BALP) and osteocalcin. Bone resorption was measured by monitoring creatinine adjusted urinary deoxypyridinoline (Dpd) concentration. Blood and urinary samples were collected from corticosteroid treated infants (n = 19) immediately before the start (Td-pre), three weeks after the start (Td-end), and two (Td-post2) and four weeks (Td-post4) after the end of the dexamethasone course. Untreated patients (n = 30) had specimens taken at week 3 (Twk-3), 6 (Twk-6), 8 (Twk-8), and 10 (Twk-10) of postnatal age. Results: Serum concentrations of BALP and osteocalcin at Td-end were significantly lower than pretreatment levels and the levels at the corresponding time point (Twk-6) of the non-treatment group. In contrast, urinary Dpd concentration at Td-end was not significantly decreased compared with the pretreatment level. However, it was significantly lower than the urinary Dpd concentration at Twk-6 of the non-treatment group. The rate of increase in lower leg length was significantly higher in the non-treatment group between weeks 3 and 6 than in the corresponding period during dexamethasone treatment in the corticosteroid group. Conclusion: Systemic corticosteroid causes appreciable suppression of serum BALP and osteocalcin and, to a lesser extent, urinary Dpd. The results suggest that corticosteroid inhibits bone growth mainly by decreasing bone formation.

Randomised crossover trial of salbutamol aerosol delivered by metered dose inhaler, jet nebuliser, and ultrasonic nebuliser in chronic lung disease

AIMS To compare the efficacy of salbutamol delivered by metered dose inhaler (MDI), jet nebuliser, and ultrasonic nebuliser in ventilated infants with chronic lung disease. METHODS Twenty preterm ventilated infants with chronic lung disease were enrolled in two studies. In study 1 (n=10), each infant was given 200 μg of salbutamol at 4 hour intervals and in random sequence from a metered dose inhaler–spacer device, a jet nebuliser, and an ultrasonic nebuliser with a small medication cup. The infants were monitored for heart rate, transcutaneous pO2, pCO2, and oxygen saturation, respiratory system resistance and compliance before and after each treatment. Infants in study 2 (n=10) were similarly studied except for the use of a different jet nebuliser. RESULTS The mean (SEM) maximum percentage decreases in respiratory system resistance, observed at 30 minutes after aerosol delivery were study 1: MDI: 44.3 (4.3)% ; jet: 32.3 (3.4)% ; ultrasonic: 56.1 (3.2)% ; study 2: MDI: 28.6 (1.0)% ; jet: 16.9 (1.4)% ; ultrasonic: 42.1 (1.6)%. During the first hour after treatment, a significantly faster heart rate and higher transcutaneous pO2 were associated with the use of the ultrasonic nebuliser or MDI than with the jet nebulisers in both studies. The use of the ultrasonic nebuliser but not the other devices also resulted in a lower transcutaneous pCO2 and improved respiratory system compliance in study 2. CONCLUSIONS These findings suggest that among the devices tested, the delivery of salbutamol aerosol to the lower respiratory tract was greatest using the ultrasonic nebuliser, and least with the jet nebulisers.

Classical galactosaemia in Chinese: A case report and review of disease incidence

Abstract: We report a case of galactose‐1‐phosphate uridyl transferase (GALT) deficiency in a full‐term Chinese neonate, who presented with atypical biochemical features of hyperammonaemia in addition to the classical presenting features of jaundice and lethargy after feeding. Red cell GALT activity was virtually absent in the patient while 50% of normal activity was found in parents and a sibling. Mutation screening excluded both Q188R and N314D as the causative mutation in GALT gene, which suggested a possible genetic segregation among ethnic groups. Data from a Taiwan screening program suggested that the incidence of the disease was approximately 1 in 400 000 in the Chinese population which was a sixth of that in Caucasian populations.

Isolated congenital tuberculosis otitis in a preterm infant

We report an unusual case of localized congenital tuberculosis otitis in a preterm infant. Unlike disseminated congenital cases, the manifestations of localized otitis are associated with a triad of signs: (i) regional lymphadenopathy in the absence of typical systemic features of tuberculosis; (ii) delayed onset of presentation; and (iii) refractory otitis unresponsive to conventional antimicrobial agents. The need for greater diligence in looking for neonatal tuberculosis is emphasized, especially in an ethnic or socioeconomic environment where the disease is prevalent.Congenital tuberculosis, otitis, preterm

Is homozygous α-thalassaemia a lethal condition in the 1990s?

Two cases of homozygous α‐thalassaemia who received active treatment in accordance with parental wishes are reported. One infant survived and the other, although successfully weaned off mechanical respiratory support, unexpectedly developed portal vein thrombosis and died. Homozygous a‐thalassaemia, a condition previously considered to be universally fatal, and an indication for therapeutic abortion, is now potentially curable with advances in diagnostic technology and treatment. However, active management of these cases raises serious ethical questions and has major financial implications on the health‐care system. Invasive prenatal and intensive postnatal interventions should remain experimental and cannot be recommended as routine clinical practice until the questions of long‐term neurodevelopmental outcome, and the morbidity and mortality associated with bone‐marrow transplantation have been fully addressed. As a result of advances in information technology, more and more parents of affected foetuses are likely to request active treatment.