PubMed Health⌕ Search

Biomedical subjects

T J Lissauer

Publications and source records attributed to T J Lissauer.

7 recordsLinked to original sources
PubMed2001

Incarcerated inguinal hernia in premature babies--a report of two cases.

UNLABELLED: We highlight the morbidity of incarcerated inguinal hernia in very low birthweight (VLBW) infants by presenting a report of two cases. Our aim is to raise the question of the optimal timing of surgery when this common problem presents on the neonatal unit. In each of our cases the hernia was diagnosed but surgery was delayed, as per normal policy on the unit, pending growth of the baby and improvement in respiratory status. Both babies suffered significant morbidity when the hernias subsequently became acutely incarcerated. CONCLUSION: In conclusion, we question whether the widespread practice of delayed surgery for inguinal hernia in VLBW infants should be reconsidered.

Hernia, Inguinal↗
PubMed1989

A comparison of the rheologic properties of neonatal and adult blood.

A number of studies have indicated that the rheologic properties of neonatal blood are different from those of the adult. The frequent administration of blood components to the neonate during intensive care make it important that these differences be established and their causes understood. The purpose of this study was to make a detailed comparison of the rheologic properties of neonatal and adult blood, with particular emphasis on low shear rate viscosity and rouleaux-related phenomena. The viscometric data was obtained from seven preterm (PT) and 18 normal term (NT) babies and compared with those from 18 adults (A). In the present study, viscometry was performed over a wide range of shear rates, from about 0.3 to 130 s-1, and the low shear rate data were compared with direct measurement of rouleaux formation using the Myrenne Erythrocyte Aggregometer. A major factor leading to the viscometric differences observed was the high hematocrit common in the newborn (46.8 +/- 2.1% PT, 52.8 +/- 6.1% NT, 44.1 +/- 2.5% A males, 40.5 +/- 1.9% A females). However, this tended to be compensated for by the lower plasma viscosity (1.05 +/- 0.07 mPas PT, 1.23 +/- 0.14 mPas NT, 1.34 +/- 0.08 mPas A--no sex difference) and reduced rouleaux formation observed in the newborn and more marked in the preterm baby. The lowered levels of red cell aggregation were found not to be due to cellular differences between the adults and the babies but rather to differing plasma components. The presence of the fetal variant of fibrinogen and low levels of immunoglobulins, especially IgM and IgA, are likely to be of particular importance.

Adult↗
PubMed1989

Interrelationships among abnormal cardiotocograms in labor, meconium staining of the amniotic fluid, arterial cord blood pH, and Apgar scores.

A prospective study of the relationships among fetal heart rate pattern, meconium staining of the amniotic fluid, umbilical cord artery pH, and Apgar score was carried out in 1219 consecutive births. Interpretable cardiotocogram patterns and cord arterial pH and blood gas analysis were obtained in 698 cases. The sensitivity of an abnormal cardiotocogram at any time for acidosis (more than 1 SD below the mean, pH less than 7.17) was 80%, and for severe acidosis (more than 2 SDs below the mean, pH less than 7.085) was 83%. However, the predictive value was low, and 32% of fetuses had an abnormal cardiotocogram but no acidosis. If only cardiotocogram abnormality in the first stage of labor was considered, sensitivity was still 47% for acidosis and 67% for severe acidosis, and the false-positive rate was reduced to only 14%. We attempted to improve the prediction of acidosis by including meconium staining of the amniotic fluid, but 65% of the variation in umbilical cord artery pH and 72 and 86% of the variation in 1- and 5-minute Apgar scores, respectively, remained unexplained. In light of these poor correlations, the current practice of considering cardiotocogram abnormality, meconium staining of the amniotic fluid, acidosis, and low Apgar scores as indicating one single disorder, "fetal distress," is not valid.

Acidosis↗
PubMed1988

Quantification of cardiovascular instability in premature infants using spectral analysis of waveforms.

Spectral analysis was applied to blood pressure and cerebral blood flow velocity recordings in premature infants with respiratory distress in order to quantify respiration-induced cardiovascular variability. Aortic blood pressure was transduced via an umbilical arterial catheter and cerebral blood flow velocity measured in the anterior cerebral artery using a 10 MHz continuous wave Doppler velocimeter in 16 infants less than or equal to 32 wk gestational age. Spectral analysis of the resulting waveforms revealed heart rate and respiratory rate components whose relative amplitudes (heart rate/respiratory rate amplitude ratio) represent an index of that component of variability induced by respiratory events. The mean (heart rate/respiratory rate amplitude) ratio was 47.2 in spontaneously breathing infants and rose to 165.9 in infants who were ventilated during muscle paralysis (p = 0.0003). Cerebral blood flow velocity recordings showed R components in only 22 of 38 simultaneous recordings. This method can be used to quantify respiration-induced cardiovascular variability and its response to therapy, and may provide a means of identifying infants at risk from brain injury due to an inability to regulate cerebral blood flow.

Blood Flow Velocity↗
PubMed1986

The relation between the need for intubation at birth, abnormal cardiotocograms in labour and cord artery blood gas and pH values.

A consecutive series of 56 infants of 32 weeks gestation or more who were resuscitated at birth by endotracheal intubation was studied to determine the occurrence of abnormal cardiotocograph traces and acidosis as determined by cord artery blood measurements. Thirty-two infants (57%) had neither cardiotocographic abnormalities nor acidosis; in this group the factors associated with the need for intubation were meconium stained amniotic fluid, operative delivery, anaesthetic agents given to the mother, a tight nuchal cord, and traumatic vaginal delivery. The need for intubation at birth should not automatically be regarded as evidence of intrapartum hypoxia or disturbed acid-base balance.

Apgar Score↗
PubMed1984

Neonatal herpes simplex pneumonia.

A neonate with herpes simplex pneumonia is described. Herpes simplex infection should be considered in the differential diagnosis of pneumonia in newborn infants, even in the absence of clinically apparent herpes in the mother.

Herpes Simplex↗