Use of a modified tracheal tube in a child with traumatic bronchial rupture:A case report and review of literature

BACKGROUND Trauma is one of the leading causes of death in the pediatric population.Bronchial rupture is rare,but there are potentially severe complications.Establishing and maintaining a patent airway is the key issue in patients with bronchial rupture.Here we describe an innovative method for maintaining a patent airway.CASE SUMMARY A 3-year-old boy fell from the seventh floor.Oxygenation worsened rapidly with pulse oxygen saturation decreasing below 60%,as his heart rate dropped.Persistent pneumothorax was observed with insertion of the chest tube.Fiberoptic bronchoscopy was performed,which confirmed the diagnosis of bronchial rupture.A modified tracheal tube was inserted under the guidance of a fiberoptic bronchoscope.Pulse oxygen saturation improved from 60%to 90%.Twelve days after admission,right upper lobectomy was performed using bronchial stump suture by video-assisted thoracic surgery without complications.A follow-up chest radiograph showed good recovery.The child was discharged from hospital three months after admission.CONCLUSION A modified tracheal tube could be selected to ensure a patent airway and adequate ventilation in patients with bronchial rupture.

Study of Linearization of Hill Dose-Effect Curve with Metabolic Velocity Instead of Drug Concentration

Objective To explore the velocity-effect relationship in order to the establish linearization of effect on an equation with regard to the consistency of the Hill dose-effect expression with the metabolic kinetics of receptors.Methods The linear velocity-effect expression was obtained by solving multivariant differential equation groups,which were established to compare the coincidences and basic relations between the Hill dose-effect and metabolic kinetic Michaelis-Menten equation for receptors.The validation test was conducted with acetylcholine,adrenaline,and their mixture as model drugs.Results The linear velocity-effect modelling was represented in vivo or in vitro,for single and multidrug systems.Pharmacodynamic parameters,especially suitable for multicomponent CMM formulas,could be determined and calculated for single or multicomponent formulas at high saturating or low linear concentration for receptors.The validation test showed that the pharmacodynamic parameters of acetylcholine were:k,2.675×10^-3s^-1;ka,5.786×10^-9s^-1;km,2.500×10^-7s^-1;α,4.619×10^9张s·mg^-1;E0,13张(P<0.01)and those of adrenaline were:k,1.415×10^-3s^-1;ka,5.846×10^-9s^-1;km,2.300×10^-7s^-1;α,-1.627×10^9张s·m g^-1;E0,9.2张(P<0.01).For the mixture of the two components,the values were:α,1.375×1010张s·m g^-1;-6.150×10^9张s m g^-1for acetylcholine and adrenaline,respectively,and E0was7.08张in both,with the other parameters unchanged(P<0.01).Conclusion The velocity-effect equation can linearize the Hill dose-effect relationship,which can be applied to study the pharmacodynamics and availability of CMM formulations in vivo and in vitro.