Low plasma triiodothyronine concentrations and outcome in preterm infants

A major association has been found between low plasma triiodothyronine concentrations in preterm neonates and their later developmental outcome. Plasma triiodothyronine concentration was measured longitudinally in 280 preterm infants below 1850 g birth weight. Babies whose lowest recorded concentration was less than 0.3 nmol/l had, at 18 months' corrected age, 8.3 and 7.4 point disadvantages in Bayley mental and motor scales and a 8.6 point disadvantage on the academic scale of Developmental Profile II, even after adjusting for a range of antenatal and neonatal factors known to influence later development. Low concentrations of triiodothyronine were strongly associated with infant mortality, but not after adjusting for the presence of respiratory illness. There was no association between plasma triiodothyronine concentrations and somatic growth up to 18 months, and no association with necrotising enterocolitis or later cerebral palsy. Data on postnatal changes in plasma triiodothyronine concentrations are presented for reference purposes. While cited reference ranges for plasma triiodothyronine concentration appear suitable for well infants above 1500 g birth weight, smaller or ill babies often have very low values for many weeks. Our data are relevant to the debate on endocrine 'replacement' treatment in premature babies.

Plasma testosterone in preterm infants with cryptorchidism

Cryptorchidism is common in infants born preterm, yet the mechanism for its occurrence is still debated. In a study of 21 premature babies with cryptorchidism at 18 months post-term and 21 case matched controls, cryptorchid preterm infants failed to show the normal rise in plasma testosterone in the first postnatal week. This rise is thought to relate to residual maternal human chorionic gonadotrophin in the neonatal circulation. Infants with cryptorchidism also failed to show the later testosterone surge in the second month which has been related to endogenous gonadotrophin release. We speculate that inadequate stimulation of testosterone release by human chorionic gonadotrophin in the fetus might contribute to the pathogenesis of cryptorchidism in preterm infants. Our findings have implications for the medical treatment or possible prophylaxis of undescended testes in premature babies.

Early sodium intake and later blood pressure in preterm infants

The relation between early salt intake and later hypertension is debated. As part of a larger feeding study, 347 preterm infants were randomly assigned to receive early diets differing grossly in sodium content. Feeding a high sodium preterm formula in the neonatal period did not influence arterial blood pressure at 18 months (corrected) age.

Maternal fatness and viability of preterm infants

To investigate the effect of maternal fatness on the mortality of infants born preterm up to the corrected age of 18 months 795 mother-infant pairs were studied. Maternal fatness was defined by Quetelet's index (weight/(height] and all infants weighed less than 1850 g at birth. In 771 mother-infant pairs maternal age, complications of pregnancy, mode of delivery, parity, social class, and the baby's sex and gestation were analysed by a logistic regression model for associations with infant mortality (but deaths from severe congenital abnormalities and those occurring during the first 48 hours after birth were excluded). In a subgroup of 284 mother-infant pairs all infant deaths except those from severe congenital abnormalities were analysed in association with the infant's birth weight and gestation and the mother's height and weight; this second analysis included another 24 infants who had died within 48 hours after birth. In the first analysis mortality overall was 7% (55/771), rising from 4% (71/173) in thin mothers (Quetelet's index less than 20) to 15% (6/40) in mothers with grades II and III obesity (Quetelet's index greater than 30). After adjusting for major demographic and antenatal factors, including serious complications of pregnancy, maternal fatness was second in importance only to length of gestation in predicting death of infants born preterm. In the second analysis mortality overall was 15% (44/284), rising from 9% (5/53) in thin mothers to 47% (8/17) in mothers with grades II and III obesity. In both analyses the relative risk of death by 18 months post-term was nearly four times greater in infants born to obese mothers than in those born to thin mothers. In addition, maternal fatness was associated with reduced birth weight, whereas it is associated with macrosomia in term infants. These data differ fundamentally from those reported in full term babies of obese mothers. It is speculated that the altered metabolic milieu in obesity may reduce the ability of the fetus to adapt to extrauterine life if it is born preterm.

Factors associated with maternal choice to provide breast milk for low birthweight infants

Factors associated with maternal choice to provide milk for premature infants were investigated in 925 mother/infant pairs in five hospitals. A well educated, married, primiparous mother aged 20 or over who delivered a baby boy by caesarean section was nearly 1000 times more likely to choose to express her milk than a mother who was poorly educated, single, multiparous, and aged under 20, delivering a female infant vaginally. Evidence from the five centres suggested that hospital staff have little influence on a mother's choice of feeding method. The major differences between the populations of babies whose mothers do or do not choose to provide milk, raise important issues concerning the interpretation of data from non-randomised clinical trials of feeding premature infants.

Shunt nephritis: report of two cases and review of the literature

We report two cases of glomerulonephritis associated with infection of cerebrospinal fluid shunts inserted for the treatment of hydrocephalus and comment an another 70 cases reported in the world literature. Although infection of CSF shunts is common, the development of glomerulonephritis is rare. Non-pathogenic bacteria are the commonest infecting organisms. Antibiotics are generally ineffective in eradicating the infection and the glomerulonephritis, but removal of the shunt is usually, though not always, associated with complete resolution of the renal disease.

Xylene poisoning: a report on one fatal case and two cases of recovery after prolonged unconsciousness

Three cases of xylene poisoning occurred after prolonged inhalation of paint fumes. Analysis showed that xylene comprised more than 90% of the solvent in the paint, the total solvent comprising 34% of the paint by weight. One patient was dead on admission, while the other two recovered after at least 15 hours' loss of consciousness. Both patients had transient liver cell damage, and one temporary impairment of renal function.

Effects of power frequency voltages on amputated human limb

Carter, A. O., and Morley, R. (1969).Brit. J. industr. Med.,26, 224-230. Effects of power frequency voltages on amputated human limb. Electric voltages of between 40 and 500 V at 50 Hz and 120 and 240 V direct were applied to freshly amputated mid-thigh legs connected to a heart-lung machine. Current and voltage were recorded against time. The direct currents showed a rise of current with time and caused little skin damage. The make and break of the current caused contractions of the muscles. The alternating currents produced by voltages between 30 and 80 V showed a steady rise with progressive skin damage. With alternating voltages of 250 and 500 V the current showed a rapid rise, with an equally rapid fall after a period of time. The current wave-form was nonsinusoidal and, after the fall, showed unidirectional impulses. Muscular contraction was tonic but later became clonic due to the impulses of current. This progression has been described in held-on electric shock accidents.

Electric current flow through human skin at power frequency voltages

Carter, A.O., and Morley R. (1969).Brit. J. industr. Med.,26, 217-223. Electric current flow through human skin at power frequency voltages. Alternating power voltages were applied to small pieces of living skin. Current and voltage were recorded continuously using voltages from 25 V to 250 V. At the lower voltages the skin appeared unaffected, but rapid destruction occurred at the higher voltages. It is concluded that skin impedance, whilst being extremely variable on account of many physical factors, is dependent on voltage and time of application in the range where dangerous electric shock occurs to human beings at power frequencies.

An evaluation of the safety of shrouded nozzels used on high-pressure greasing equipment

High-pressure grease guns using a shrouded nozzle were `fired' from varying distances at amputate lower limbs to determine the pressure at which penetration of the skin occurred. It was concluded that a shrouded nozzle would not normally give rise to injury if the grease pressure was below 7,000 lbf./sq. in (492 kgf./cm.²).

Injuries due to accidental injection of paint from high-pressure paint guns

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