Nuclear power plant accidents which cause radiation injuries have rarely occurred in the world. In Japan, we have experienced no case of radiation injuries related to nuclear power plant accidents. However, we have experienced several cases of radiation injuries, which have occurred in the field of radiation devices. Medical staffs that treat externally exposed patients have no reason to fear their own exposure to these patients, because external exposure causes no harmful effects to the treating staff if precautionary guide lines are followed. Patients who are contaminated by radioactive substances (¹³⁷Cs, ²³⁹Pu and etc) should be treated carefully. In order to prevent the secondary exposure and contamination by patients, the medical staff should employ the prevention principle (shield, distance and treatment time). Radiation-induced bone marrow injuries can be successfully treated with blood transfusion, some kinds of cytokines (rhG-CSF, etc) and radioprotectors. However, present-day medical treatment is limited for patients suffering from either intestinal or central nervous system injuries. In the case of contaminated radiation burns, life-saving treatment should be the first priority, and then burns should be decontaminated and treated medically. In order to eliminate internally contaminating radioactive substances, many kinds of chelating agents (DTPA for ²³⁹Pu and iodine-chloride for ¹³¹I, etc) can be adopted. The medical staffs that is required to treat exposed and contaminated patients should have full knowledge of radiation injuries and acquire skill in the treatment of radiation contamination.

View full abstract

The risk of cardiopulmonary arrest (CPA) while taking a hot bath has long been recognized in the elderly. Although extensive studies have been conducted concerning the prevention of such events in the elderly, an effective system of prevention and care has yet to be developed. We conducted a retrospective investigation of 71 elderly patients, aged 65 and over, who were treated at Kitasato University Hospital Emergency Center from April 1987 to March 1997 for incurring CPA while taking a bath. This investigation revealed: 1) over the course of the ten-year period, the mean yearly incidence tended to increase (7.1 persons); 2) CPA during bathing occurred twice as frequently in women as men; 3) many of the patients had a pre-existing condition such as hypertension (46.3%) or diabetes mellitus (27.8%); 4) sixty-three (98.4%) of the patients had already undergone CPA by the time emergency personnel had arrived. All 71 patients died (mortality was 100%); 5) this phenomenon occurred 14 to 20 times more frequently during the winter months between 20:00 and 24:00 hours than during the summer months; 6) in all cases, CPA occurred while the subjects were bathing him-or herself. The time taken to find the subjects averaged 43.9±33.2 minutes as reported by the family members. Transfer time from the bath to our emergency center took approximately 31.5±12.8 minutes; 7) only three patients were reported to have consumed alcohol before taking a bath; 8) among 22 patients (75.9%) on whom an autopsy was performed, the primary cause of CPA was ischemic heart failure due to coronary sclerosis in 15 cases (68.2%), and also, subarachnoid hemorrhage recognized in one case and acute aortic dissection in one case (4.5%).

View full abstract

The purpose of this study was to evaluate the increased organ blood flow induced by acetazolamide (AZ) by comparing changes in blood flow (BF) in organs and levels of vasodilation factors after administration of AZ and CO₂ inhalation. Method: The BF in the livers, kidneys, stomach walls, and abdominal muscles of rabbits were measured with a laser flowmeter while AZ was administered. In addition, cardiac output, and levels of PGI₂, endothelin (ET-1), and NO were measured. These measurements were also made while CO₂ was inhaled. Result: BF in the rabbit liver and kidney were increased by AZ administration. However, BF in the stomach wall and the abdominal muscle, as well as levels of PGI₂, ET-1, and NOx remained unchanged after AZ administration. On the other hand, BF in all 4 organs, and the levels of PGI₂ and ET-1, increased while CO₂ gas was inhaled. Conclusion: The results suggest that the increase in BF in response to AZ was specific to the liver and kidney both of which contain large quantities of carbonic anhydrase, therefore, the mechanism of AZ-induced vasodilation was thought either to result from retention of CO₂, or from a mechanism different from the inhibition of CO₂.

View full abstract

Transport of a patient with acute respiratory distress syndrome (ARDS) is a crucial problem. A 17-year-old severe hypoxemic woman was transported successfully using mobile extracorporeal lung assist (mobile ECLA). The patient was injured in a massive landslide and admitted to a municipal hospital far about 103km away from our hospital. On admission, a right tension pneumothorax, hemothorax, 2-7 rib fractures and pulmonary contusion were diagnosed. Although intensive therapies were performed, ARDS developed and her oxygenation deteriorated on the 5th hospital day. Arterial oxygen tension (PaO₂) was 35 mmHg with a fractional inspired oxygen (F^IO₂) of 1.0 and a positive end-expiratory pressure (PEEP) of 8cmH₂O. After the initiation of veno-venous ECLA with a centrifugal pump, her PaO₂ increased to 232mmHg. She was successfully transported under mobile ECLA during the 2.5 hour transport from the municipal hospital to our ICU. We believe that mobile ECLA is a useful method for inter-hospital transport of a patient with ARDS. To our knowledge, this may be the first case of long distant inter-hospital transport on mobile ECLA in Japan.

View full abstract

We encountered a case of sinus arrest in a patient with total paresis at the C4 level associated with dislocation of the 5th cervical vertebra. Sinus arrest was noted on postinjury days 5, 13 and 21. Transthoracic pacing and transvenous pacing were performed to treat the sinus arrests. Artificial cardiac pacing was terminated and Holter ECG was started on postinjury day 35. Sinus arrest was not noted after day 35. Bradycardia attributed to parasympathotonia was considered the cause of the sinus arrest. Although temporary pacing is not useful in treating sinus arrest which occurs only once or recovers after a few seconds, it should be used in cases of recurrent sinus arrest or sinus arrest which persists for more than 1 minute. Furthermore, intensive continuous monitoring for more than a month including ECG is recommended in patients with cervical spinal cord injuries.

View full abstract