Existence of an exceptional reaction pathway for H3(+) formation observed in collision-induced dissociation of methane ions at 1000 eV.

Dissociation of CH(4)(+) ions at 1000 eV induced by collision with Ar atoms was investigated by measuring the kinetic energies of the ionized fragments. At small scattering angles, including zero, H(+), H(2)(+), H(3)(+), CH(3)(+), CH(2)(+), CH(+), and C(+) fragments were observed. The attractive part of the potential in the CH(4)(+)-Ar collision system played an important role in the formation of the ionized fragments. Rainbow scattering, leading to a large scattering cross section, was shown to be responsible for the increased formation of H(3)(+). It is proposed that on collision-induced dissociation of CH(4)(+), its three hydrogen atoms, which form a triangle, simultaneously react and move together to form H(3)(+).

[Case of caffeine poisoning survived by percutaneous cardio-pulmonary support].

A 17-year-old woman presented to the Emergency Department of our hospital following a suicide attempt. She reported having ingested 340 tablets of caffeine, each of which contained 200mg of caffeine, about 3 hours earlier. Soon after arrival, her blood pressure dropped, and electrocardiography revealed sinus tachycardia and ventricular tachycardia (VT). Subsequently, she developed ventricular fibrillation (VF), and VF was resistant to pharmaceutical interventions and even to cardioversion. Therefore, we performed percutaneous cardiopulmonary support (PCPS). This resulted in disappearance of VF and tachycardia, symptoms of caffeine poisoning, and improvement was observed 16 hours after the start of PCPS. In our case, caffeine poisoning symptoms disappeared without blood purification, after PCPS had stabilized her circulation. Based on our observations in this case, stabilization of the circulation using PCPS in severe caffeine poisoning with VF, a potentially fatal arrhythmia, is a significantly beneficial strategy.

[Pathophysiologic changes in trauma patients and indications of damage control surgery].

Damage control surgery has become an inevitable strategy in the treatment of severely traumatized patients. Rationale for the DCS is the fact that the mortality in surgical patients who developed hypothermia, acidosis, and coagulopathy (lethal triad) is extremely high unless patients' physiologic stability was reestablished. DCS is usually indicated when patient shows signs of lethal triad during surgical operation. As most of patients who subsequently needed DCS could be judged as having most severe injuries during resuscitative phase, it may be more wise to select candidates for DCS during this phase than to indicate DCS during operation.