Immediate allergic cross-reactivity to levobupivacaine and ropivacaine.

Allergic reactions to amide local anaesthetic agents are rare. We report the case of a 74-year-old man who suffered anaphylaxis, presenting with cardiovascular collapse, immediately after receiving regional anaesthesia on two separate occasions, the first involving the use of levobupivacaine and the second using ropivacaine. Skin testing revealed positive reactions to both levobupivacaine and ropivacaine, and negative reactions to articaine and lidocaine. Severe allergic reactions can be caused by the amide local anaesthetic drugs, levobupivacaine and ropivacaine.

Solving modulated structures by X-ray and electron crystallography.

X-ray diffraction can be used for accurately determining not only classical, ordinary structures, but also modulated ones. For structures with weak modulations, the modulation induced satellite reflections are often hard to be observed by X-ray diffraction, but they appear clearly in electron diffraction. In these cases, X-ray diffraction will give only average structures whereas electron diffraction will yield information about the modulations. Sr(1.4)Ta(0.6)O(2.9) is a complex modulated compound with weak modulation and small modulated domains. Here we demonstrate the power of combining X-ray and electron crystallography for studying modulated structures on powders. The modulations of Sr(1.4)Ta(0.6)O(2.9) were determined from electron diffraction (SAED) and high resolution electron microscopy (HREM) images. With specially developed image processing techniques, the weak modulations were enhanced, facilitating the interpretation of HREM images in terms of atomic structure.

Crystal structure of moganite-type phosphorus oxynitride: relationship to other twinned-quartz-based structures.

The structure of moganite-type phosphorus oxynitride quenched from high-pressure high-temperature conditions has been refined using neutron powder diffraction data. This moganite-type structure, space group I2/a, Z = 12, is slightly less distorted with respect to the Imab aristotype than is moganite (a monoclinic form of silica). A close topological relationship has been identified between the moganite-type and orthorhombic BeH(2) structures indicating that SiO(2), PON and BeH(2) all adopt structures belonging to the twinned-quartz-based group. This group represents another possible structure type for systems composed of corner-sharing AX(4) tetrahedra. Structures of this group are obvious candidates for intermediate phases between the cristobalite and quartz types.

Evaluation of caudal anaesthesia performed in conscious ex-premature infants for inguinal herniotomies.

Ex-premature infants, before 45 weeks postconceptional age, are at high-risk of apnoea after surgery. General anaesthesia increases the risk of apnoea. We evaluated the tolerance and the efficiency of caudal anaesthesia performed in 25 consecutive conscious ex-premature infants for inguinal herniotomies. N2O/O2 and EMLA cream are used to facilitate caudal puncture. Anaesthesia procedure, patient comfort and complications following the 24 postoperative hours were studied. We report good anaesthesia conditions without compromising the baby's comfort and few perioperative complications. Only two infants with a prior history of apnoea or bronchopulmonary dysplasia had apnoea during and after surgery. A total spinal anaesthesia was the major complication in one infant and prolonged surgery requiring general anaesthesia was the main limitation of this technique in another child. The principal advantage of the procedure is to facilitate and simplify the postoperative management of the babies. The anaesthetic technique does not alter surgical conditions. Caudal epidural anaesthesia performed in awake high-risk preterm infants is beneficial for these infants but requires experienced operators.