Multi-institutional and multi-disciplinary care: A successfully managed aortic dissection in the third trimester of pregnancy.

Multi-disciplinary collaborative care for pregnant women with complex and emergent conditions is essential. Logistical planning, clear communication and human factor awareness are all non-clinical skills which need to be utilised in order to maximise outcomes. We describe the case of a proximal aortic dissection in the late third trimester of pregnancy diagnosed in a peripheral hospital that was transferred to a cardiothoracic centre for successful operative management 160 km away. This required the time-sensitive mobilisation and liaison of a receiving cardiothoracic, anaesthesiology and perfusionist team in conjunction with obstetric and midwifery support from an affiliated maternity hospital, as well as the national neonatal transport team. We emphasise the importance of multidisciplinary team management in complex cases and how imperative good inter-disciplinary communication is to ensure safe inter-hospital transfer.

Inhaled nitric oxide in preterm infants with prolonged preterm rupture of the membranes: a case series.

The available evidence does not support the routine use of inhaled nitric oxide (iNO) in the care of premature infants. We present a case series of 22 preterm infants born after prolonged preterm premature rupture of membranes and oligohydramnios with respiratory failure. Oxygenation index decreased significantly after commencement of iNO.

Methemoglobin levels in umbilical cord blood of women with intrauterine growth restriction and preeclampsia.

OBJECTIVE: To measure nitric oxide (NO) levels, as assessed by methemoglobin (MetHb), in the umbilical cord arterial blood of women with preeclampsia (PE), normotensive pregnancies with intrauterine growth restriction (IUGR, <10th percentile for birth weight) and normotensive pregnancies with appropriate for gestational age (AGA) infants. DESIGN/METHODS: Prospective analysis of MetHb levels in umbilical arterial blood of pregnancies with PE, normotensive IUGR and normotensive AGA infants using spectrophotometry. Exclusion criteria included cigarette smoke exposure, hemolytic disorders, chronic hypertension, any significant medical illness and medications affecting NO or MetHb levels. RESULTS: There were 42 women in the PE, 42 in the AGA and 37 in the IUGR group. Maternal age, mode of delivery, gravidity, parity and infant gender were similar in the three groups. MetHb levels were significantly lower in the IUGR group compared to the AGA group (p < 0.01). MetHb levels, while higher in the PE group compared to the AGA group, did not reach statistical significance. CONCLUSION: Our data suggests that NO may play a key role in the pathogenesis of IUGR. We also, for the first time, provide information on umbilical arterial MetHb levels in PE, normotensive IUGR and normotensive AGA pregnancies.

Mechanisms of high-order perturbative photoemission from Cu(001).

We observed high-order 2- to 4-photon photoemission and above threshold photoemission (ATP) processes with 3.07 eV light from the Cu(001) surface. The intensity of 3-photon photoemission via excitation through the n = 1 image potential state significantly exceeded that of the 2-photon process. The ATP occurs either via single photon transitions from the image potential resonances above the vacuum level or by multiphoton transitions from image potential states below the vacuum level. The experimental ratio of the m- to (m + 1)-photon process yields is sensitive to the electronic band structure of the solid.

Surface magnetism during oxygen-aided Fe homoepitaxy.

Magnetization-induced optical surface second harmonic generation (SHG) in the longitudinal geometry was used to study magnetism on the p(1 x 1)O/Fe(001) surface during a layer-by-layer Fe growth with surfactant oxygen. Considerable one-monolayer oscillations were observed. Minima of the magnetization-induced contributions to the second order dielectric susceptibility were detected at half-filled monolayers. These contributions were accessed either by measuring a purely magnetic SHG yield, or indirectly from the magnetization dependence of the overall SHG signal, both providing consistent results. The origin of the oscillatory surface magnetism is consistent with the expected oscillating oxygen induced relaxation due to the surface Fe islands.

Platelet adhesion to foreign surfaces under controlled conditions of whole blood flow: human vs rabbit, dog, calf, sheep, pig, macaque, and baboon.

Our results reveal significant differences between mammalian species with respect to platelet adhesion to foreign surfaces exposed to heparinized, flowing blood. In particular, we have demonstrated the following: 1) At a surface shear rate characteristic of shear rates in mammalian arteries, human platelet adhesion (and that of calf, baboon, macaque, hog or sheep) is negligible in comparison to dog or rabbit platelet adhesion after 10 mins of blood flow. 2) The species differences are biomaterial dependent: the human-dog difference is present with Cuprophan or Avcothane, but absent with compressed Gore-Tex or fluorinated ethylcellulose. (The platelets of humans and dogs adhere to comparable degrees on the latter 2 biomaterials.) 3) With Cuprophan and recirculated blood, the human-dog difference persists at 30 and 180 mins. 4) By means of videomicroscopy, the species differences are unlikely only to be an artifact of the possible formation and embolization of surface-adherent aggregates. Tests for the thromboresistance of candidate biomaterials and for platelet adhesion under controlled flow conditions must therefore begin to take into account differences between humans and other species.