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Abstract: Wave propagation in compliant tubes filled with streaming fluids is usually handled with the method of characteristics. The latter refies however on one-dimensional flows, so violating the no-slip condition that real fluids satisfy on solid walls. The impact of this one-dimensional simplification has apparently not been investigated, which justifies the present two-dimensional approach. Here, a steady, inviscid and incompressible basic flow of arbitrary velocity profile Uo(r) and arbitrary cross-sectional mean velocity Ūo streams in a long, uniform, thin walled, compliant tube. The propagation of long-wavelength, small-amplitude perturbations is studied with a normal mode analysis. Analytical solutions show the importance of Uo(r). For example, if Uo(r) satisties the no-slip condition, then upstream wave propagation occurs regardless of Ūo. This questions the one-dimensional wave propagation theory and could possibly influence the interpretation of several physiological experimental data relying upon it, mainly in the vascular and respiratory systems.

Thirty patients presenting with phlebographically confirmed deep venous thrombosis were treated with a very low molecular weight heparin fragment (CY 222) in an open and prospective phase-2 trial. A uniform dosage of 750 IC anti-factor Xa units/kg/day was administered subcutaneously for 10 days or more to patients whose thromboses were categorized as postsurgical (17 cases) or medical (13 cases). The clinical symptoms of venous thrombosis diminished in 93% of the patients overall. The extent of vascular clearing was assessed by an original scoring system which compared the pre- and posttreatment phlebo-graphies. The effect of treatment was globally rated ‘very good’ (more than 75 % lysis) in 37% of the patients, ‘good’ (about 50% lysis) in 40% and ‘poor’ (0–25% lysis) in 17%; the phle-bographic thrombosis worsened in 6.6%. Little change occurred in laboratory tests exploring thrombolysis, but a strong anti-factor Xa activity was detected.

A case of neuromuscular blockade of about 200 min of duration, in a 9-year-old boy from mivacurium 0.15 mg·kg−1 is reported. The diagnosis was delayed, after onset of the first signs of recovery, due to the lack of monitoring of neuromuscular transmission. The neuromuscular blockade was reversed with neostigmine 0.04 mg·kg−1. Complete reversal required fifty minutes. The presence of an abnormal genetic variant of pseudocholinesterases was demonstrated by the measurements of pseudocholinesterase activity and dibucaine number. The importance of monitoring of neuromuscular transmission for diagnosis and treatment of mivacurium-induced neuromuscular blockade is underlined.