Comparison of emergency transport for acute alcohol intoxication before and after the coronavirus disease 2019 pandemic: A retrospective observational study.

The ongoing coronavirus disease 2019 (COVID-19) pandemic has had a broad effect on social, economic, educational, and political systems. We investigated the effect of COVID-19 on emergency transportation due to acute alcohol intoxication in the Kochi Prefecture in Japan, a region with high alcohol consumption. This retrospective observational study was conducted using the data of 62,138 patients from the Kochi-Iryo-Net database, Kochi Prefecture's emergency medical and wide-area disaster information system. Chi-square tests and multiple logistic regression analyses were performed to examine the association between emergency transportation and alcohol intoxication. This analysis compared the monthly number of transportations during 2019 (as reference) with that throughout 2020 and 2021. Approximately 1.5 % of all emergency transportation cases were related to acute alcohol intoxication. The number of emergency transportation cases due to acute alcohol intoxication declined by 0.5 % in 2020 and 0.7 % in 2021 compared with that in 2019. Moreover, compared with that in 2019, the number of cases of emergency transportation due to acute alcohol intoxication significantly decreased in 2020 (incidence rate ratio: 0.78; 95 % confidence interval: 0.67-0.91) and 2021 (incidence rate ratio: 0.73; 95 % confidence interval: 0.63-0.86). Lifestyle changes due to the COVID-19 pandemic affected the number of emergency transports due to acute alcohol intoxication in 2020 and 2021 (during the COVID-19 pandemic) compared to that in 2019 (before the pandemic).

Water Adsorption on Hydrophilic Fibers and Porous and Deliquescent Materials: Cellulose, Polysaccharide, Silica, Inorganic Salt, Sugar Alcohol, and Amino Acid.

Water adsorption isotherms are systematically summarized by using celluloses and polysaccharides as hydrophilic crystal/amorphous materials with functional groups, silicas as hydrophilic porous materials, and inorganic salts, sugar alcohols, and amino acids as hygroscopic deliquescent materials. For hydrophilic fibers such as celluloses and polysaccharides, water was adsorbed on amorphous solids, and water clusters were formed around functional groups. For porous materials such as silicas, capillary condensation occurred in the micropores of silicas. For deliquescent materials such as inorganic salts, sugar alcohols, and amino acids, water adsorption rapidly increased stepwise at a specific threshold relative humidity, accompanied with a structure transformation to a liquid state. In addition, the water activity (Aw) of materials used in packed products was able to be estimated from the water adsorption isotherms of the pure component. This indicated that the deliquescent materials have a great effect on the depression of Aw for the suppression of microbial growth at an extremely high water content. The deliquescent materials could be useful to develop new environmentally and sustainable products and technologies with the mediation of water vapor and/or hydration.

Photocatalytic dehydrative etherification of alcohols with a nanoporous gold catalyst.

A simple and efficient photocatalytic approach for dehydrative etherification of alcohols has been developed by a nanoporous gold catalyst. This protocol features no requirement of addition of acids or bases, broad substrate generality, and excellent acid-sensitive functional group tolerance. The mechanistic studies demonstrate the heterogeneous nature of the catalytic system and the recyclability of the catalyst was demonstrated repeatedly.

Impact of school closures on pediatric ambulance transport in Japan.

BACKGROUND: After the coronavirus disease (COVID-19) pandemic, nationwide school closures were implemented in many countries. This study aimed to determine the impact of the school closures on pediatric ambulance transport, comparing the situation before and after the COVID-19 pandemic. METHODS: This retrospective observational study was conducted using data from the Kochi-Iryo.net database. In Kochi prefecture, schools were closed from March 6 to May 24, 2020. Pediatric emergency transport during the school closure period in 2020 was compared with that in the same period in 2019 (before the COVID-19 pandemic) and in 2021 (when schools were not closed). Statistical analysis comprised χ2 tests with Bonferroni adjustments for multiple testing. To adjust for patient backgrounds, we also performed multiple logistic regression analyses for numbers of pediatric ambulance transports. RESULTS: The rate of pediatric ambulance transports was significantly lower (p = 0.008) in 2020 (276; 3.97%) than in 2019 (391; 4.87%), but there was no significant difference (p = 0.360) between 2019 (391; 4.87%) and 2021 (352; 4.56%). Multivariable analysis revealed similar trends (2019 vs. 2020: OR 0.86, 95% CI 0.73-1.00; 2019 vs. 2021: OR 0.96, 95% CI 0.82-1.11). Regarding the characteristics of pediatric ambulance transport journeys, there were no significant differences in 2019, 2020, and 2021 in terms of sex, severity, locations of ambulance stations, and disease classification. CONCLUSIONS: There was a decrease in pediatric ambulance transportation due to the public health interventions for COVID-19, including school closures. However, this decrease was not solely due to school closures.

Oral Absorption across Organotypic Culture Models of the Human Buccal Epithelium after E-cigarette Aerosol Exposure.

Inhaled aerosols are absorbed across the oral cavity, respiratory tract, and gastrointestinal tract. The absorption across the oral cavity, which is one of the exposure routes, plays an important role in understanding pharmacokinetics and physiological effects. After aerosol exposure from e-cigarettes, tissue viability studies, morphological observation, and chemical analyses at the inner and outer buccal tissues were performed using organotypic 3D in vitro culture models of the buccal epithelium to better understand the deposition and absorption on the inner and outer buccal tissues. The aerosol exposures did not affect the tissue viability and had no change to the tissue morphology and structure. The deposition ratio at the buccal tissue surface is relatively low. This shows that majority of aerosol transfers to the airway tissues. The distribution from the inner tissue to the outer tissue has selectivity among various compounds, depending on the affinity with the liquid crystal structure of phospholipids and glucosylceramide. Although nicotine absorption in the aqueous solution was well known to increase as the unprotonated state of nicotine increased, the nicotine absorption after the aerosol exposure is irrelevant to the protonated-unprotonated state. Furthermore, the results showed that half of nicotine that adhered to the oral cavity transferred to the inner tissue via the oral epithelium and the other half transferred to the gastrointestinal tract accompanying multiple executions of swallowing, while majority of the water-soluble compounds with the hydroxyl group such as propylene glycol and benzoic acid that adhered to the oral cavity were eluted with the saliva and transferred to the gastrointestinal tract by swallowing.

Enhanced Protein Adsorption Capacity of Macroporous Pectin Particles with High Specific Surface Area and an Interconnected Pore Network.

There has been much interest in developing protein adsorbents using nanostructured particles, which can be engineered porous materials with fine control of the surface and pore structures. A significant challenge in designing porous adsorbents is the high percentage of available binding sites in the pores owing to their large surface areas and interconnected pore networks. In this study, continuing the idea of using porous materials derived from natural polymers toward the goal of sustainable development, porous pectin particles are reported. The template-assisted spray drying method using calcium carbonate (CaCO3) as a template for pore formation was applied to prepare porous pectin particles. The specific surface area was controlled from 177.0 to 222.3 m2 g-1 by adjusting the CaCO3 concentration. In addition, the effects of a macroporous structure, the specific surface area, and an interconnected pore network on the protein (lysozyme) adsorption capacity and adsorption mechanism were investigated. All porous pectin particles performed rapid adsorption (∼65% total capacity within 5 min) and high adsorption capacity, increasing from 1543 to the highest value of 2621 mg g-1. The results are attributed to the high percentage of available binding sites located in the macropores owing to their large surface areas and interconnected pore networks. The macroporous particles obtained in this study showed a higher adsorption capacity (2621 mg g-1) for lysozyme than other adsorbents. Moreover, the rapid uptake and high performance of this material show its potential as an advanced adsorbent for various macromolecules in the food and pharmaceutical fields.

Acute effect of the COVID-19 pandemic on emergency transportation due to acute alcoholic intoxication: a retrospective observational study.

BACKGROUND: The COVID-19 pandemic has caused changes in people's drinking habits and the emergency management system for various diseases. However, no studies have investigated the pandemic's impact on emergency transportation for acute alcoholic intoxication. This study examines the effect of the pandemic on emergency transportation due to acute alcoholic intoxication in Kochi Prefecture, Japan, a region with high alcohol consumption. METHODS: A retrospective observational study was conducted using data of 180,747 patients from the Kochi-Iryo-Net database, Kochi Prefecture's emergency medical and wide-area disaster information system. Chi-squared tests and multiple logistic regression analyses were performed. The association between emergency transportation and alcoholic intoxication was examined. The differences between the number of transportations during the voluntary isolation period in Japan (March and April 2020) and the same period for 2016-2019 were measured. RESULTS: In 2020, emergency transportations due to acute alcoholic intoxication declined by 0.2%, compared with previous years. Emergency transportation due to acute alcoholic intoxication decreased significantly between March and April 2020, compared with the same period in 2016-2019, even after adjusting for confounding factors (adjusted odds ratio 0.67; 95% confidence interval 0.47-0.96). CONCLUSIONS: This study showed that lifestyle changes due to the COVID-19 pandemic affected the number of emergency transportations; in particular, those due to acute alcoholic intoxication decreased significantly.

Synthesis of High Specific Surface Area Macroporous Pectin Particles by Template-Assisted Spray Drying.

Many types of porous particles containing inorganic and organic substances, such as carbon, metals, metal oxides, inorganic-organic hybrids, and polymers, have been developed. However, natural polymer-derived particles are relatively rare. To our knowledge, this report describes the first synthetic method for obtaining meso-/macroporous particles made from pectin, which is a natural polymer with a wide range of biological activities suitable for active substance support applications. These porous particles were prepared using a template-assisted spray-drying method, followed by a chemical etching process. An organic template [i.e., poly(methyl methacrylate) (PMMA)] or an inorganic template [i.e., calcium carbonate (CaCO3)] was used to evaluate the resulting formation of macroporous structures in the pectin particles. Furthermore, the concentration of the templates in the precursor solution was varied to better understand the mechanism of porous pectin particle formation. The results showed that the final porous particles maintained the characteristic properties of pectin. The differences between the two templates resulted in two distinct types of porous particles that differed in their particle morphologies (i.e., spherical or wrinkled), particle sizes (ranging from 3 to 8 µm), pore sizes (ranging from 80 to 350 nm), and pore volume (ranging from 0.024 to 1.40 cm3 g-1). Especially, the porous pectin particles using the CaCO3 template have a significantly high specific surface area of 171.2 m2 g-1, which is 114 times higher than that of nonporous pectin particles. These data demonstrated the potential for using PMMA and CaCO3 templates to control and design desired porous materials.

Irreversible adsorption of acidic, basic, and water gas molecules on calcium-deficient hydroxyapatite.

Hydroxyapatite [Ca10(PO4)6(OH)2, HAP] has P-OH Brønsted acidic sites, Ca2+ Lewis acidic sites, and OH- and O2- basic sites on which acidic and basic gas molecules can be selectively adsorbed, and has no micropore onto which various molecules adsorb regardless of the chemical properties of gas molecules. The interaction between the surface sites and acidic and basic gas and water molecules has been investigated by evaluating the adsorption properties of various molecules on the surfaces of calcium-deficient HAP. The specific adsorption sites were assessed by examining the reversible and irreversible adsorption of NH3, CO2, aldehydes, and water vapor on HAP at the temperature of 298 K, using two HAP samples with different Ca/P ratios, but similar structures and surface areas: Ca-deficient HAP with an extreme lower Ca/P ratio (named P-HAP) and one with a higher Ca/P ratio (named C-HAP). Irreversible adsorption of NH3 on C-HAP is attributed to the adsorption on both Ca2+ Lewis acidic and P-OH Brønsted acidic sites. Irreversible adsorption on P-HAP is attributed to the adsorption on P-OH Brønsted acidic sites only. Irreversible adsorption of CO2 occurred on C-HAP only, and preferentially on OH- basic sites. Acetaldehyde undergoes a catalytic reaction over both OH- basic sites and surface P-OH Brønsted acidic sites at 298 K. Water irreversible adsorption was extensively observed for P-HAP, and water was barely desorbed at low pressures. In situ powder X-ray diffraction showed an asymmetric expansion of the lattice in the [100] direction, indicating that water was incorporated into P-HAP crystals, especially on structural OH- sites. Irreversible adsorption of acidic and basic molecules was therefore less observed on P-HAP than on C-HAP, but P-HAP had considerable irreversible adsorption of water vapor with associated asymmetric lattice expansion. The incorporation of water vapor was first observed and could be useful to improve adsorption or catalytic performance with the mediation of water vapor and/or hydration.

Prehospital removal improves neurological outcomes in elderly patient with foreign body airway obstruction.

OBJECTIVE: In Japan, the number of patients with foreign body airway obstruction by food is rapidly increasing with the increase in the population of the elderly and a leading cause of unexpected death. This study aimed to determine the factors that influence prognosis of these patients. METHODS: This is a retrospective single institutional study. A total of 155 patients were included. We collected the variables from the medical records and analyzed them to determine the factors associated with patient outcome. Patient outcomes were evaluated using cerebral performance categories (CPCs) when patients were discharged or transferred to other hospitals. A favorable outcome was defined as CPC 1 or 2, and an unfavorable outcome was defined as CPC 3, 4, or 5. RESULTS: A higher proportion of patients with favorable outcomes than unfavorable outcomes had a witness present at the accident scene (68.8% vs. 44.7%, P=0.0154). Patients whose foreign body were removed by a bystander at the accident scene had a significantly high rate of favorable outcome than those whose foreign body were removed by emergency medical technicians or emergency physician at the scene (73.7% vs. 31.8%, P<0.0075) and at the hospital after transfer (73.7% vs. 9.6%, P<0.0001). CONCLUSIONS: The presence of a witness to the aspiration and removal of the airway obstruction of patients by bystanders at the accident scene improves outcomes in patients with foreign body airway obstruction. When airway obstruction occurs, bystanders should remove foreign bodies immediately.

Evaluation of residual toxic substances in the stomach using upper gastrointestinal endoscopy for management of patients with oral drug overdose on admission: a prospective, observational study.

The guidelines on the indications for gastric lavage were published in 1997, and a less-aggressive initial approach has been used for poisoned patients. Clinical studies have shown that the outcomes of retrieval of residual toxic substances in the stomach are variable and that no beneficial effect is obtained. However, the presence of residual toxic substances in the stomach before gastric lavage has not been estimated. The objective of this study was to evaluate the residual stomach contents on admission of patients with oral drug overdoses using upper gastrointestinal endoscopy. A 2-year prospective study of 167 patients with oral drug overdoses was performed. Endoscopy was performed on admission to observe the gastric body, fornix, and pyloric antrum. Patients were classified into 3 groups according to the digestive phase (tablet/food phase, soluble/fluid phase, and reticular/empty phase). The groups were compared with respect to time elapsed since ingestion, and numbers and variety of orally overdosed drugs. The numbers of patients in each phase were as follows: tablet/food phase, 73; soluble/fluid phase, 50; and reticular/empty phase, 44. The tablet/food and soluble/fluid phase groups contained the greatest numbers of patients who presented within 1 to 2 hours since ingestion. In the tablet/food group, only 12 of 73 patients (16%) presented within 1 hour since ingestion, and 3 patients presented >12 hours since ingestion. In the soluble/fluid phase group, only 9 of 50 patients (18%) presented within 1 hour since ingestion, and 2 patients presented >12 hours since ingestion. The reticular/empty phase group contained the greatest number of patients presenting within 2 to 4 hours since ingestion, and 3 patients presented within 1 hour since ingestion. The residual stomach contents before lavage were variable in all of the groups. The residual gastric content before the performance of gastric lavage is variable in overdosed patients on admission. This may influence the efficiency of gastric lavage with respect to retrieval of residual toxic substances in the stomach. This study may contribute to the development of a strategy for treating patients who have orally overdosed on drugs in the future.

Gymnastic Formation-related Injury to Children in Physical Education.

OBJECTIVE: Current data indicate that the rate of trauma in children during gymnastic formation is increasing, especially while creating a structure with a certain height, such as the human pyramid. The goal of the present study was to clarify the clinical characteristics of these injuries. METHODS: In this single-institution review, all children treated for a gymnastic formation-related injury at Nippon Medical School Hospital from 2013 through 2015 were identified through the institution's registry. The injury mechanism was classified, and injury severity, interventions, and outcome were examined. RESULTS: Eight children were treated for a gymnastic formation-related injury. They were 7 boys and 1 girl aged 10 to 15 years (mean age, 13.1±1.8 years). Neurotrauma ranging from concussion to spinal cord injury without radiographic abnormality occurred in 6 patients (75%). No intracranial hemorrhagic lesions were detected. The Glasgow Coma Scale score on arrival was 15 in all 8 patients, and neurological deficits were present in 1 patient. No patient required surgical intervention. All patients made a full recovery after discharge from the hospital. No patients died. The average follow-up period was 2.1±0.9 weeks. CONCLUSIONS: Neurotrauma is a frequent result of gymnastic formation accidents in children. Healthcare workers and teachers should recognize this type of injury, and public education that targets parents should be introduced.

Benzalkonium chloride intoxication caused by intravenous self-injection.

BACKGROUND: Benzalkonium chloride (BZK) is widely used as a germicide in hospitals and other places. Although several cases of accidental oral intake of BZK have been reported, there have been few reported cases of BZK toxicity due to intravenous injection. CASE REPORT: A male nurse in his 40 s injected 15 mL of 10% BZK (Osvan S) directly into his left antebrachial vein while at home, as a suicide attempt. The patient was admitted to our hospital 1 hour later. Acute respiratory distress syndrome (ARDS) was diagnosed by blood gas analysis, chest X-ray, and CT scan. Due to extracorporeal blood purification therapy, including hemoperfusion and plasma exchange, serum BZK became undetectable. However, the ARDS was not improved. Extracorporeal blood purification therapy consisting of continuous hemodiafiltration (CHDF) was continued to treat the ARDS. After performing CHDF for the next 36 hours, improvement of both the PaO2/FiO2 ratio and chest X-ray findings was noted. Tracheal extubation was performed on day 9 and no further complications occurred after this period, he was discharged on day 21. CONCLUSION: Extracorporeal blood purification therapy is probably effective for treatment of BZK intoxication by intravenous injection.

Successful retrieval using ultrathin transnasal esophagogastroduodenoscopy of a significant amount of residual tricyclic antidepressant following serious toxicity: a case report.

BACKGROUND: In Japan, ultrathin transnasal esophagogastroduodenoscopy (EGD) with a 4.9-mm diameter endoscope (Olympus XP260) is routinely used to examine the upper gastrointestinal tract. This procedure does not require sedation and does not affect vital signs. Gastric lavage is not empirically employed in the management of all poisoning patients. It is considered only for potentially life-threatening overdoses when the procedure can be performed within 1 h of ingestion of the poison. However, there are no absolute indications for gastric lavage. EGD may increase the indications, efficiency and safety of gastric lavage in poisoning patients. FINDINGS: A 35-year-old female was admitted to our emergency department 2 h after ingesting multiple drugs, including a critical dose of the tricyclic antidepressant (TCA) amitriptyline, at which time she was confused and had a Glasgow Coma Scale score of 8 (E1V2M5). Endotracheal intubation was performed. To confirm the type of TCA and in order to determine whether gastric lavage was required, we decided to perform EGD. Endoscopy demonstrated adherence of residual drugs to the stomach wall, in a soluble form and not as a mass. Hence, gastric lavage was performed via the EGD to avoid passage of these drugs into the small bowel. The patient was extubated on day 2, without the development of complications such as aspiration pneumonia, and was discharged on day 5. CONCLUSION: EGD may be useful in poisoning patients for determining the amount of residual drug in the stomach, also allowing direct observation of the effectiveness of gastric lavage.

Gastric lavage guided by ultrathin transnasal esophagogastroduodenoscopy in a life-threatening case of tobacco extract poisoning: a case report.

Nicotine, which is found in tobacco, is one of the most toxic of all known poisons. A 31-year-old woman was brought to our emergency department 2 hours after ingesting a usually fatal dose of a tobacco extract. Although gastric lavage was once commonly used to treat poisoning cases of this type, lavage can lead to such complications as aspiration, hypoxia, oropharyngeal and gastric trauma, and electrolyte disturbances. Recent guidelines have suggested less-aggressive gastric-emptying procedures as initial treatments. Currently, there are no absolute indications for gastric lavage use. The present patient had a history of depressive episodes and had attempted suicide by ingesting an extract derived from 20 cigarettes mixed with alcohol. There was no evidence of vomiting or seizures occurring before arrival of the ambulance. Physical examination revealed no signs of sweating, although the patient appeared to be confused, which is often seen with nicotine intoxication. She admitted using 2 kinds of cigarette, each of which typically contain 11.2 mg of nicotine. The patient's nicotine level was suspected to be higher than 40 to 60 mg, which is normally fatal. To determine whether gastric lavage was indicated in this case, we performed ultrathin transnasal esophagogastroduodenoscopy, which neither requires sedation nor compromises the airways. Although 2 hours had passed since ingestion, the tobacco extract and food were directly visualized within the stomach. Subsequently, gastric lavage was performed with 2,000 mL of water administered through a nasogastric tube. Ultrathin esophagogastroduodenoscopy made it possible to directly observe the gastric lavage and to ensure the stomach contents had been completely removed. No changes were noted in the vital signs, and no obstruction of the airways was observed. The patient recovered quickly and was discharged the following day. Ultrathin esophagogastroduodenoscopy helped determine the diagnosis and ensure that gastric lavage had been performed without complications.

Medical relief activities, medical resourcing, and inpatient evacuation conducted by Nippon Medical School due to the Fukushima Daiichi Nuclear Power Plant accident following the Great East Japan Earthquake 2011.

On March 11, 2011, after the Great East Japan Earthquake and tsunami, the government declared a nuclear emergency following damage to the Fukushima Daiichi Nuclear Power Plant. A second hydrogen explosion occurred on March 14 at the plant's No. 3 reactor and injured 11 people. At that time the prime minister urged people living 20 to 30 km from the Daiichi plant to stay indoors. Under these circumstances, many residents of Iwaki City, which was largely outside the 30-km zone, left the city, making it difficult to get supplies to the remaining residents. The only transportation route open for supplies and medical resources was roads, and many drivers feared the rumor that the city was contaminated by radioactive materials and, so, refused to go there. Nippon Medical School (NMS) heard that medical resources were running short at Iwaki Kyoritsu Hospital, which requested water, medications, food, fuel (gasoline), medical support, and the evacuation of 300 inpatients. As a first step, NMS decided to evaluate the situation at the hospital and, on March 16, the director of the NMS Advanced Emergency Center visited the hospital and helped provide triage for about 200 patients. Critically ill patients receiving ventilatory support were given priority for evacuation because they would be most at risk of not being able to evacuate should the Japanese government order an immediate evacuation of the city. We tried to evacuate the inpatients via an official framework, such as the Disaster Medical Assistance Team (DMAT), but DMAT could not support this mission because this hospital was not within the 30-km evacuation zone. Moreover, the Iwaki City government could not support the evacuation efforts because they were fearful of the rumor that Iwaki was contaminated by radioactive material. Ultimately, we realized that we had to conduct the mission ourselves and, so, contacted our colleagues in the Tokyo metropolitan area to prepare enough hospital beds. We evacuated 15 patients to 8 hospitals over a 5-day period. As a result, we could reduce the number of patients at Iwaki Kyoritsu Hospital, and, thereby, the collapse of medical services in the city was avoided. In retrospect, someone might say the government--either central or local--should ideally have carried out this mission and created a system by which to do it. At the same time, however, to overcome any future bureaucratic issues, we should also prepare private networks, such as those used by NMS, because they can respond flexibly to unexpected large-scale disasters.

Traumatic renal artery occlusion treated with an endovascular stent--the limitations of surgical revascularization: report of a case.

When renal artery occlusion occurs secondary to blunt trauma, the recovery rate of renal function after open revascularization is varied and far from satisfactory. Although the optimal treatment for this type of injury has not been established, percutaneous revascularization by endovascular stenting has recently been advocated for patients with unilateral renal artery occlusion. We herein report a case of blunt renal artery occlusion treated with an endovascular stent. After the placement of the stent, renal arteriography showed multiple nonflow-limiting contrast defects in the distal renal arteries, suggesting peripheral thrombosis. Although the duration of warm renal ischemia appears to be the crucial determinant of renal function, multiple thrombi in the distal renal arteries, which would be undetectable during open surgery, could also affect the functional outcome. The presence of these thrombi may explain the limited success of surgical revascularization in such cases.

Visceral ischemia caused by acute aortic dissection following blunt aortic injury: report of a case.

The diagnosis and management of blunt thoracic aortic injuries have seen significant changes over the last decade. The purposeful delay of definitive repair by aggressive blood pressure management has been suggested to be safe, and deliberate nonoperative management may be a reasonable alternative in selected patients with minimal aortic injuries detected with contrast-enhanced computed tomography. We report a case of acute aortic dissection due to blunt thoracic aortic injury resulting in splanchnic ischemia, for which we selected primarily nonoperative management, because the aortic tear was small but was complicated by multiple trauma. Although acute aortic dissection is an uncommon presentation of blunt injuries of the thoracic aorta and the poor prognosis has not been adequately emphasized, close observation, to evaluate the dissection and to determine whether splanchnic ischemia has developed, is recommended for patients for whom delayed definitive repair or nonoperative management has been selected.