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Introduction: In patients presenting with intra-abdominal tumor and peritoneal carcinomatosis, cytoreductive surgery associated with hyperthermic chemotherapy may offer improved survival. We describe a case of diaphragmatic paralysis following that kind of procedure., Case Report: A 60-year-old woman presented with respiratory insufficiency following cytoreductive surgery and intra-abdominal hyperthermic chemotherapy performed for pseudomyxoma intraperitonei. Pulmonary function assessment demonstrated a restrictive pattern. Three successive chest CT-scans demonstrated a thinning diaphragm muscle. Respiratory insufficiency eventually led to the death of our patient., Conclusion: We conclude in favor of a muscular degeneration of the diaphragm consecutive to the combined effect of cytoreductive surgery and intraperitoneal chemotherapy. Owing to the unusual nature of this complication, we did not consider it as a hypothesis at an early point in this patient's management. We think physicians should be aware of such a complication in order to consider it in a timely way. We recommend performing a biopsy of the diaphragm for pathology examination to assess muscular degeneration., (Copyright © 2016 SPLF. Published by Elsevier Masson SAS. All rights reserved.)

The diaphragm as a striated muscle is characterized by the repetition of a single element arranged in series: the sarcomere containing two kinds of myofilaments: a thick one constituted by the myosin, and a thin one primarily composed of actin. The myosin molecule consists of two heads where two myosin heavy chains (MHC) are fixed, a flexible hinge with two light (MLC) chains, and long rod-shaped tails. The diaphragm contains 4 MHC isoforms (MHC-slow, MHC-2A, MHC-2B, MHC-2X) and 6 MLC isoforms (MLC-1f, MLC-3f, MLC-1sa, MLC-1sb, MLC-2f, MLC-2s/v). In humans, the diaphragm contains mainly fibers expressing the isoforms MHC-slow, MHC-2A, and MLC-2f, MLC-2s et MLC-1f. For the mechanical properties of the different isoforms, there is a gradient from the MHC-slow to the MHC-2A, MHC-2B and MHC-2X/2B. According to the circumstances, the diaphragm will adapt towards a slow profile (COPD, cardiac failure and in animals: Duchenne muscular dystrophy, denervation-1 week, age-female, corticosteroids, chronic stimulation), or a fast profile (in animals: chronic hypoxia, denervation-2 weeks, age-males) or a more oxidative profile (in animals: cachexia, obesity). The reasons why the diaphragm adapts towards a slower or a faster muscle are not known. In fact, for a given pathological situation, several factors are able to influence the fiber composition of the diaphragm. Therefore, the net result of the influence of these different factors in terms of MHC and MLC diaphragm adaptation is difficult to predict.

P-phenylenediamine (PPD) induces skeletal muscle lesions in rats which have been chosen as a model for investigation of the inflammatory and degenerative pattern of the muscle fibers. With the use of histochemical and ultrastructural criteria, the morphology of the lesions have been analysed in the diaphragm. Fifteen minutes after the induction by PPD, a subsarclemmal oedema can be shown by electron microscopy. Enzymatic changes appear during the first hour. The pathologic features are more prominent after twenty-four hours. The lesions are characterized by a segmental necrosis adjacent to unaltered fibers and by particular types of fibers such as target, snake coils, core fiber. A comparison between the lesions induced by PPD and those occurring during other types of myopathies has been made.

The effect of a sustained-release aminophylline preparation on diaphragmatic contractility was investigated in patients with stable chronic obstructive lung disease (FEV1 = 22.6% of predicted value). Ten such patients were tested before (control) and after a week's course of oral aminophylline. Diaphragmatic contractility was evaluated by measuring the transdiaphragmatic pressure generated at residual functional capacity by bilateral electrical stimulation of the phrenic nerves. The nerves were stimulated supramaximally at 1 Hz, using needle electrodes. Plasma aminophylline levels (12.5 +/- 0.9 mg/l) were within therapeutic range in all patients. After treatment with aminophylline, for each stimulation the transdiaphragmatic pressure increased significantly from 14 +/- 1.3 to 17 +/- 1.3 cm H2O (+21%; P less than 0.005). These results confirm that aminophylline increases the force of contraction of the diaphragmatic fibres electively tested by the technique used. Long-term treatment with theophylline in therapeutic doses may be of interest in such patients, as it might improve their diaphragmatic contractility and result in better control of both respiratory muscle fatigue and episodes of acute respiratory failure.

Using the electron spin resonance method, the effect of antioxydants on the number of natural organic free radicals is studied in the case of the diaphragm of the Rat. The effect observed shows an important decrease in the free radical concentration, which may, in the case of ascorbic acid and BHT, lead to their complete disappearance. These results are discussed in the light of the hypothesis according to which antioxydants play a role in the lengthening of the life span because of their fundamental character of inhibitors of free radicals.

This article concerns the electromyographical study of a synthetic curare derived from Azobis Arylimidazo (1-2a) Pyridinium (AH/8165) with a simultaneous recording of the spontaneous diaphragmatic activity and "testing" of the neuro-muscular transmission at the level of a peripheral muscle. This study shows that AH/8165 is a powerful non-depolirizing curarimimetic drug that quickly induces a neuro-muscular block at the level of the diaphragm and the peripheric muscles that can be reversed by anticholinesterasic drugs. Its reaction time is short (about 1 mn). There are importante individual variations in the duration of the neuromuscular blockage. Towards the end of the experience, tetanizing stimulations reveal a muscular fatigability in all the cases. No ill side-effects could be observed upon the cardiovascular system or any side-effects ascribable to a histaminergic mechanism.