Reduction of granulocyte-mediated lung injury in canine cardiopulmonary bypass by anisodamine infusion

Possible role for anisodamine in organophosphate poisoning

In cases of organophosphate poisoning, patients are treated with a combination of antidotes. In addition to these poison-directed antidotes, patients may require extra oxygen and artificial ventilation; other modalities may also be needed due to the wide range of toxic effects. Anisodamine is a belladonna alkaloid, and like other drugs from this family is non subtype-selective muscarinic, and a nicotinic cholinoceptor antagonist, which has been employed in traditional Chinese medicine. As a muscarinic antagonist, it displays similar pharmacological effects to atropine and scopolamine. However, anisodamine is not only less potent than atropine and scopolamine but also less toxic. Current in vitro and animal model studies have demonstrated that anisodamine has protective effects in a variety of diseases. Organophosphate poisoning involves not only the central and peripheral nervous systems, but also the cardiac and respiratory systems, as well as activation of inflammatory processes and oxidative stress. Therefore, the anticholinergic and additional activities of anisodamine appear to be relevant and justify its consideration as an addition to the existing remedies. However, more research is needed, as at present data on the role of anisodamine in the management of organophosphate poisoning are limited. Here, we review the beneficial effects of anisodamine on processes relevant to organophosphate poisoning.

Lung perfusion with protective solution relieves lung injury in corrections of Tetralogy of Fallot

BACKGROUND

The aim of this study was to evaluate the protective effect of pulmonary perfusion with hypothermic protective solution on lung function after cardiopulmonary bypass in corrections of Tetralogy of Fallot.

METHODS

Sixty-four consecutive children with Tetralogy of Fallot were randomly divided into a control group (n = 30) and a protective group (n = 34). Hypothermic protective solution was infused to the main pulmonary artery in the protective group. Hemodynamics and lung functions were monitored. Concentrations of malondialdehyde, tumor necrosis factor-alpha, von Willebrand factor, and endothelin in plasma were measured. The interleukin-6 and interleukin-8 levels in bronchoalveolar lavage fluid were also determined. Lung biopsy specimens were obtained after weaning from cardiopulmonary bypass.

RESULTS

Oxygenation values (oxygen index and alveolar-arterial O(2) gradient) were better preserved in the protective group than in the control group. The time of mechanical ventilation and length of intensive care unit stay were shorter in the protective group compared with the control group. The tumor necrosis factor-alpha and malondialdehyde levels in plasma increased in both groups after operations, and the rising extents were lower in the protective group than in the control group. The von Willebrand factor and endothelin levels in plasma increased more significantly in the control group than in the protective group. The concentrations of interleukin-6 and interleukin-8 in bronchoalveolar lavage fluid were lower in the protective group than in the control group. The examination of histopathology demonstrated capillary hyperemia and hemorrhage, intra-alveolar edema, leukocytes accumulation, mitochondria swelling and vacuolation, and gas-blood barrier broadening in the control group, whereas there were no significant changes in the protective group. The intercellular adhesion molecule-1 expression on lung vascular endothelial cells was stronger in the control group.

CONCLUSIONS

Lung perfusion with hypothermic protective solution during cardiopulmonary bypass relieved lung injury in corrections of Tetralogy of Fallot. The inhibition of lung vascular endothelial cell injury may be the major mechanism of relieving cardiopulmonary bypass-induced lung injury.

Protective effect of anisodamine on reperfusion injury of skeletal muscles in rabbit

Anisodamine is an alkaloid isolated from a Chinese plant, which was subsequently synthesized. Its chemical structure is similar to atropine. It inhibits cholinergic nerve function, improves microcirculation, and was reported to have a protective effect on reperfusion injury in various organs. We used anisodamine in a rabbit model with ischemia and reperfusion injury of hind limb muscles. We evaluated its effect on skeletal muscle cells, using transmission electron microscopy, and analyzed lipid peroxidation by measuring malondialdehyde and lactate dehydrogenase blood concentrations. We found that malondialdehyde and lactate dehydrogenase concentrations after 1 hour of reperfusion were lower in animals treated with anisodamine than in controls. Damage to membrane structures and myofilaments in muscle cells was less severe after anisodamine treatment. Our findings indicate that anisodamine protects skeletal muscles with ischemia and reperfusion injury.

The influence of leukocyte filtration during cardiopulmonary bypass on postoperative lung function. A clinical study

The accumulation of activated leukocytes in the pulmonary circulation plays an important role in the pathogenesis of lung dysfunction associated with cardiopulmonary bypass. Animal studies have demonstrated that the elimination of leukocytes from the circulation reduces postoperative lung injury and improves postoperative pulmonary function. We conducted a prospective randomized clinical study to evaluate whether postoperative lung function could be improved by use of a leukocyte filter during cardiopulmonary bypass. Elective coronary artery bypass grafting was done with a leukocyte-depleting arterial blood filter incorporated in the extracorporeal circuit (14 patients, leukocyte filter group) or without the filter (18 patients, control group). Blood samples collected at intervals before, during, and after operation were used for analysis of blood cell counts, elastase concentrations, and arterial blood gases. The use of the leukocyte filter caused no significant reduction in leukocyte count (p = 0.86). There were no differences in postoperative lung function between the groups, as assessed through (1) oxygenation index (290 for leukocyte filter group compared with 329 for control group, 95% confidence interval, 286 to 372, p = 0.21), (2) pulmonary vascular resistance (p = 0.10), and (3) intubation time (16.6 hours for leukocyte filter group versus 15.7 hours for control group, 95% confidence interval, 12.1 to 19.1 hours, p = 0.72). The levels of neutrophil elastase were significantly higher at the end of cardiopulmonary bypass in the leukocyte filter group (460 microgram/L in leukocyte filter group versus 230 microgram/L in control group, 95% confidence interval, 101 to 359 microgram/L, p = 0.003). We conclude that the clinical use of the present form of leukocyte-depleting filter did not improve any of the postoperative lung function parameters analyzed in this study.