Wei Fong Kao

The clinical experience of acute cyanide poisoning.

The authors reviewed the clinical manifestations, complications, and the prognosis affected by Lilly Cyanide Antidote in 21 victims of acute cyanide poisoning over a 10-year period. The clinical signs and symptoms in cyanide poisoning are variable. Among 21 cases, loss of consciousness (15), metabolic acidosis (14), and cardiopulmonary failure (9) were the three leading manifestations of cyanide intoxication. Anoxic encephalopathy (6) was not uncommon in the severely intoxicated victims. Diabetes insipidus (1) or clinical signs and symptoms mimicking diabetes insipidus (3) may be an ominous sign to encephalopathy victims. The major cause of fatal cyanide poisoning is the intentional ingestion of cyanide compounds as part of a suicide attempt. Decrease of arteriovenous difference of O2 partial pressure may be a clue for the suspicion of cyanide intoxication. Although the authors cannot show a statistically significant difference (P = .47) for the Lilly cyanide antidote kit in terms of improving the survival rate for victims of cyanide poisoning, the antidote kit was always mandatory in our study in the cases of severely intoxicated victims who survived. Early diagnosis, prompt, intensive therapy with antidote, and supportive care are still the golden rules for the treatment of acute cyanide poisoning, whether in the ED or on the scene.

Athletic performance and serial weight changes during 12- and 24-hour ultra-marathons

Objective:The principal objective of this study was to evaluate serial weight changes in athletes during 12- and 24-hour ultra-marathons and to correlate these changes with athletic performance, namely the distance covered. Design:This was a prospective study. Setting:The 2003 Soochow University international ultra-marathon. Participants:Fifty-two race participants. Interventions:12- or 24-hour ultra-marathon. Main Outcome Measurements:Body weight changes were measured before, at 4-hour intervals during, and immediately after the 12- and 24-hour races. Results:Significant overall decreases in body weight were apparent at the conclusion of both races. The mean relative body weight change after the 12-hour race was −2.89 ± 1.56%, ranging from 0 to 6.5%. The mean relative body weight change after the 24-hour race was −5.05 ± 2.28%, ranging from −0.77% to −11.40%. Of runners in the 24-hour race, 26% lost greater than 7% of baseline body weight during the race. During both the 12- and 24-hour races, the greatest weight change (decrease) occurred during the first 4 hours. Weight remained relatively stable after 8 hours, although a further decrease was apparent between 16 and 20 hours in the 24-hour participants. Weight change had no bearing on performance in the 12-hour race, whereas weight loss was positively associated with performance in the 24-hour race. Conclusions:Our findings demonstrate that the majority of weight decrease/dehydration in both the 12- and 24-hour races occurred during the first 8 hours. Hence, to maintain body weight, fluid intake should be optimized in the first 8 hours for both 12- and 24-hour runners and in 16 to 20 hours for 24-hour marathon runners.

Renal abscess: Early diagnosis and treatment

The purpose of this study was to identify initial clinical characteristics that can lead to early diagnosis of renal abscess in the emergency department and predict poor prognosis. A retrospective review of 88 renal abscess patients, from April 1979 through January 1996, was conducted. Patients were categorized into two groups. In group 1, renal abscess was diagnosed by an emergency physician, whereas in group 2 renal abscess was not diagnosed by an emergency physician. Clinical characteristics included demographic data, predisposing medical problems, duration of illness before diagnosis, time spent in hospital diagnosis, initial signs and symptoms, laboratory tests, and radiology studies that may have been useful in the early diagnostic regimes. Clinical factors were also analyzed for their value in predicting poor prognosis. The mean age of 88 patients with renal abscess was 59.8 years. The most common predisposing disorder was diabetes mellitus, followed by renal calculi and ureteral obstruction. The duration of diagnosis by emergency physicians was shorter for group 1 patients (1.2 +/- .4 v group 2, 2.8 +/- 2.9 days; P < .01) and the blood urea nitrogen level was higher in group 1 (55.7 +/- 42.2 mg/dL, v group 2, 33.5 +/- 33.5 mg/dL; P = .02). In the early diagnosis of renal abscess, emergency physicians should focus on patients who have predisposing disorders, ie, diabetes mellitus, renal stones, immunosuppression, longer duration of symptoms of urinary tract infection, and renal failure, who should promptly be investigated with ultrasound in the emergency department. The cure rate after treatment with routine antibiotics plus percutaneous drainage was 64%. This therapy is recommended for initial treatment. Poor prognosis is associated with elderly patients with lethargy and with elevation of the serum blood urea nitrogen level.

Elderly use of the ED in an Asian metropolis.

To compare emergency department (ED) use by elderly patients (age 65 yrs or older) with that by younger adult patients (age 15-64 yrs), a prospective consecutive chart review study was conducted from August 1, 1995 through May 31, 1996 in eight designated hospitals in Taipei city (which has 2.6 million residents, 8.4% of whom are 65 yrs or older). Patient age, sex, mode of arrival, living status, triage category, advanced life support (ALS) eligibility, referral, confinement to bed, intensive care unit (ICU) admission, impression, trauma mechanism, and disposition were recorded and compared between the two groups. Of 27,765 adult emergency patients studied during the 10 months, 24% were elderly. The elderly were more likely to be ambulance cases, of high acuity and ALS eligibility, living alone, bed-ridden, and ICU cases (19.4% v 10.5%, 14.8% v 5.5%, 14.7% v 4.3%, 9.7% v 4.1%, 16% v 1.1%, and 4.0 v 1.1%, respectively). The three leading illnesses in the elderly were cerebral vascular accident (6.6%), cancer (5.6%), and cardiovascular disease (5.6%), and the two most common trauma mechanisms were trip (fall from the same level surface) (57.2%) and traffic accident (20.7%). Twenty-seven percent and 22.7% of elderly were disposed to admission and observation, respectively, compared with the 10.9% and 11.4% of the younger patients. Elderly patients have significantly different and more severe presentations to the ED compared with younger adults.

Acute Toxicities of Betel Nut: Rare but Probably Overlooked Events

Background: Betel nut chewing has long been a social habit in Taiwan and other Asian and tropical countries. It produces various autonomic and psychoneurologic effects including tachycardia, flushing, warmth, cholinergic activation, alertness, and euphoria. Although the oral carcinogenic effects are well known, data concerning its acute toxicity are few. To better understand the toxicity of betel nut, cases reported to the Taiwan Poison Control Center as probable or possible betel nut–related toxicity (January 1988–June 1998) were reviewed. In the 17 cases suitable for review (14 males, 3 females, age 21 to 60 years), the most common manifestations were tachycardia/palpitations ; tachypnea/dyspnea ; hypotension and sweating ; vomiting, dizziness, and chest discomfort ; abdominal colic, nausea, numbness, and coma ; and acute myocardial infarction and related manifestations . The reported quantity of betel nut used was low (1 to 6 nuts), except an extract of 100 betel nuts was used in 1 case and 66 chewed in another. Most cases recovered within 24 hours after the exposure. One patient developed probable acute myocardial infarction and ventricular fibrillation and died despite repeated cardiac defibrillation. Although betel nut chewing is widespread, significant toxicity as reported to a poison center is rare. Because most betel nut–related effects are transient and mild in nature, the incidence of such events is likely to be underreported. Nevertheless, betel nut chewing can produce significant cholinergic, neurological, cardiovascular, and gastrointestinal manifestations. It is possible that it may aggravate cardiac diseases in susceptible patients but this hypothesis must be further investigated. Treatment is symptomatic. With timely support, rapid and complete recovery is anticipated but a small risk of major complications cannot yet be discounted.

Clinical Factors and Outcomes in Patients with Acute Mesenteric Ischemia in the Emergency Department

Background: The purpose of this study was to determine the initial clinical characteristics of acute mesenteric ischemia and identify variables associated with adverse outcomes in the emergency department (ED). Methods: The charts of 124 consecutive patients with surgically and pathologically identified acute mesenteric ischemia from September 1990 to September 2000 were reviewed retrospectively to obtain data about demographics, initial clinical presentations, predisposing diseases, previous medications, laboratory tests, and common findings on computed tomography scans with contrast. Only patients admitted through the ED and treated on medical or surgical wards were enrolled. Results: Mean patient age was 71.1 years (range, 25‐100 years). The overall mortality rate was 50%. There were no significant differences in gender, underlying disease, previous medication, initial signs and symptoms, and causes of mesenteric infarction, between survivors and non‐survivors. Univariate analysis demonstrated that older age, bandemia, hepatic and renal impairment, hyperamylasemia, metabolic acidosis, hypoxia, intramural pneumatosis, and septic syndrome, were more frequent in patients who died than in those who survived (p < 0.05). Logistic regression identified the following variables as independent predictors of death: old age (odds ratio, OR, 1.077; 95% confidence interval, CI, 1.013, 1.146; p = 0.02); bandemia (OR, 3.894; 95% CI, 1.160, 13.074; p = 0.03); elevated serum aspartate aminotransferase (AST; OR, 4.532; 95% CI, 1.274, 16.122; p = 0.02); increased blood urea nitrogen (BUN; OR, 7.219; 95% CI, 1.166, 44.696; p = 0.03); and metabolic acidosis (OR, 6.604; 95% CI, 1.804, 24.171; p < 0.01). Conclusion: A high index of suspicion and aggressive diagnostic imaging can facilitate early diagnosis and improve outcomes for patients with acute mesenteric ischemia. Risk stratification showed that elderly patients with metabolic acidosis, bandemia, or elevated AST and BUN had a poor prognosis. Greater therapeutic intervention is advocated to reduce mortality in high‐risk patients with acute mesenteric ischemia.

Ingestion of Low-Concentration Hydrofluoric Acid: An Insidious and Potentially Fatal Poisoning

STUDY OBJECTIVE The purpose of this study was to provide the first description of the effects of ingestion of low-concentration hydrofluoric acid in a population reported to a regional poison control center. METHODS A retrospective analysis of data collected by trained personnel using a standardized data collection system was performed. All charts involving hydrofluoric acid exposures for a 2-year period from a certified regional poison control center were identified by a computerized search. Each chart was abstracted by trained and blinded personnel. RESULTS There were 1,772 exposures to hydrofluoric acid; 135 involved ingestion. There were 99 cases of human hydrofluoric acid ingestion for analysis. All ingestions involved consumer products containing 6% to 8% hydrofluoric acid. Symptoms, most commonly mild gastrointestinal effects, were reported by 49 patients. Two patients with minimal effects during an observation period of 2 to 4 hours deteriorated suddenly and died. All other patients recovered completely. Of 29 cases in which calcium concentrations were recorded, 4 cases of hypocalcemia occurred. All patients who had major effects or died were adults who had ingested more than 3 ounces of hydrofluoric acid with suicidal intent. Death occurred precipitously in patients who had appeared well a few minutes earlier. CONCLUSION Death occurred in 2 patients, both of whom were adults who had ingested more than 3 ounces with suicidal intent. Ingestion of a household product containing hydrofluoric acid is a potentially life-threatening condition that requires close monitoring and prompt therapy. The abrupt deterioration and lack of warning signs indicate the need for better diagnostic methods.

Diagnosis of appendicitis with left lower quadrant pain

Abdominal pain is one of the most common chief complaints of patients presenting to the emergency department and, among the diagnoses of abdominal pain, appendicitis is the most common surgical disorder. Traditionally, the diagnosis of appendicitis is based on well-established clinical criteria combined with physician experience. However, appendicitis presenting with rare and misleading left lower quadrant (LLQ) pain may result in an initial false-negative diagnosis by the physician and even result in failure to order the subsidiary examination of computed tomography (CT) or ultrasound, so increasing the risk of perforation/abscess formation and prolonged hospital stay. In this report, we present 2 cases of atypical appendicitis with LLQ pain where the correct diagnosis was not initially considered. One patient had right-sided appendicitis; the inflamed appendix was 12 cm in length and projected into the LLQ. Local peritonitis developed during observation. With the aid of CT, the diagnosis was established in time. The other patient had left-sided appendicitis with situs inversus totalis. Adverse outcomes with appendiceal rupture and abscess formation occurred due to inadvertent physical examinations and inadequate observation. Early clinical suspicion and adequate observation are indicated in patients with uncertain clinical features. However, in patients with unresolved clinical symptoms and/or local peritonitis that develop during observation, imaging studies play a significant role in preoperative diagnosis and determination of proper treatment.

Arterial oxygen desaturation during emergent nonsedated upper gastrointestinal endoscopy in the emergency department

A prospective study was conducted to see whether emergent esophagogastroduodenoscopy (EGD) in patients with active upper gastrointestinal (GI) bleeding is associated with more oxygen desaturation than nonemergent EGD. Emergent EGD was performed in the study patients with active upper GI bleeding. Nonemergent EGD was performed in the control patients. Determination of oxygen saturation (Sao2) was measured by pulse oximeter. A decrease in Sao2 of > 4% was more frequent in the study patients (26%, 13 of 50) than in controls (6%, 3 of 50) (P < .01). During EGD, mean oxygen saturation decreased significantly in both groups of patients. After EGD, mean oxygen saturation did not recover toward the pre-endoscopy insertion level in the study group (P < .01). A linear association was found that oxygen desaturation = 5.46 + 0.15 (status) -0.06 (baseline oxygen saturation). Emergent EGD for active upper GI bleeding in the emergency department tends to be associated with more frequent significant oxygen desaturation than nonemergent EGD. Continuous oxygen supplementation and oxygen saturation monitoring may be used during emergent nonsedated EGD in the emergency department.

Epidemiology of acute mountain sickness on Jade Mountain, Taiwan: an annual prospective observational study.

Acute mountain sickness (AMS) is a pathophysiological symptom complex that occurs in high altitude areas. The AMS prevalence is reportedly 28% on Jade Mountain, the highest mountain (3952 m) in Taiwan. We conducted this study owing to the lack of annual epidemiological data on AMS in Taiwan. Between April 2007 and March 2008, 1066 questionnaires were completed by trekkers visiting Paiyun Lodge on Jade Mountain. Information in the questionnaire included demographic data, mountaineering experience, AMS history, and trekking schedule. Weather data were obtained from the Central Weather Bureau of Taiwan. The Lake Louise AMS score was used to record symptoms and diagnose AMS. The chi-square test or the Student t test was used to evaluate associations between variables and AMS. In our study, the AMS prevalence was 36%. It increased significantly at different rates at different locations on the Jade Mountain trail and varied significantly in different months. Rainy weather tended to slightly increase the incidence of AMS. A lower incidence of AMS was correlated with hig-altitude trekking experience or preexposure (p < 0.05), whereas a higher incidence of AMS was correlated with a prior history of AMS (p < 0.05). The trekkers with AMS were significantly younger, ascended faster from their residence to the entrance or to Paiyun Lodge, and ascended slower from the entrance to the Paiyun Lodge (p < 0.05), but the differences lacked clinical significance. No differences in the incidence of AMS based on blood type, gender, or obesity were observed. The most common symptom among all trekkers was headache, followed by difficulty sleeping, fatigue or weakness, gastrointestinal (GI) symptoms, and dizziness or lightheadedness. In conclusion, the AMS prevalence on Jade Mountain was 36%, varied by month, and correlated with trekking experience, preexposure, and a prior history of AMS. The overall presentation of AMS was similar to that on other major world mountains.