Biomedical subjects

Chen-Hsen Lee

Publications and source records attributed to Chen-Hsen Lee.

At least 37 records · Page 2Linked to original sources

PubMed2005

A novel in vitro retinal differentiation model by co-culturing adult human bone marrow stem cells with retinal pigmented epithelium cells.

Human retinal pigment epithelium (HRPE) cells are important in maintaining the normal physiology within the neurosensory retina and photoreceptors. Recently, transplantation of HRPE has become a possible therapeutic approach for retinal degeneration. By negative immunoselection (CD45 and glycophorin A), in this study, we have isolated and cultivated adult human bone marrow stem cells (BMSCs) with multilineage differentiation potential. After a 2- to 4-week culture under chondrogenic, osteogenic, adipogenic, and hepatogenic induction medium, these BMSCs were found to differentiate into cartilage, bone, adipocyte, and hepatocyte-like cells, respectively. We also showed that these BMSCs could differentiate into neural precursor cells (nestin-positive) and mature neurons (MAP-2 and Tuj1-positive) following treatment of neural selection and induction medium for 1 month. Furthermore, the plasticity of BMSCs was confirmed by initiating their differentiation into retinal cells and photoreceptor lineages by co-culturing with HRPE cells. The latter system provides an ex vivo expansion model of culturing photoreceptors for the treatment of retinal degeneration diseases.

Bone Marrow Cells↗

PubMed2005

Can ruptured appendicitis be detected preoperatively in the ED?

PURPOSE: The purpose of this study is to determine which clinical symptoms/signs and computed tomography (CT) signs can help in distinguishing ruptured from simple appendicitis. MATERIALS AND METHODS: The medical records and CT findings of 202 consecutive patients with surgically proven acute appendicitis were retrospectively reviewed and compared between 2 groups with and without appendiceal rupture. RESULTS: Longer duration of symptoms ( P < .001), peritoneal sign ( P = .004), and higher C-reactive protein ( P < .001) are significant clinical factors for predicting appendiceal rupture in acute appendicitis. Abscess, extraluminal air, wall defect, peritoneal enhancement, extraluminal appendolith, phlegmon, localized fluid, fascial thickening, ascites, stool impaction, and 4 patterns of bowel wall thickening ( P < .001 to P = .047) are significant CT signs for predicting appendiceal rupture. The appendiceal diameter is larger in patients with ruptured appendicitis than in those with simple appendicitis (13.2 +/- 3.2 vs 11.3 +/- 2.4 mm, P < .001). The appendolith size is larger in patients with ruptured appendicitis than in those with simple appendicitis (7.1 +/- 4.4 vs 5.1 +/- 2.8 mm, P = .018). CONCLUSION: Besides some clinical findings, CT scan can accurately determine appendiceal rupture in acute appendicitis and can further demonstrate the presence of local inflammatory mass, facilitating management decision in the emergency department (ED).

Adolescent↗

PubMed2005

Decreasing clinically significant adverse events using feedback to emergency physicians of telephone follow-up outcomes.

STUDY OBJECTIVE: We evaluate the effect on adverse events of a telephone follow-up quality improvement program. METHODS: This was a before-and-after intervention comparison based on prospectively collected data in a tertiary care hospital emergency department (ED) (82,000 visits per year). The first half (April 15 to July 31, 2001) served as control, and the second half (August 1 to November 15, 2001) served as intervention with feedback to physicians on telephone follow-up outcomes of discharged patients and resident training about the uncertain presentations of serious diseases and the need to use additional evaluation on selected patients (observation unit, hospital admission). Telephone follow-up of the high-risk patients and retrospective review of 3-day return visits were used to quantify outcome measures: return visits to EDs and clinically significant adverse events (return visits with serious misdiagnoses or an erroneous management plan). The differences in proportions of outcomes were measured with 95% confidence intervals (CIs). RESULTS: High-risk patients were enrolled: 566 (13.7%) of 4,139 discharged patients in the before-intervention period and 397 (11.3%) of 3,507 in the after-intervention period. The quality improvement initiative decreased return visits on enrolled patients from 10.1% (57/566) to 4.9% (19/397) (5.2% difference with 95% CI 1.8% to 8.8%) and decreased clinically significant adverse events from 4.1% (23/566) to 1.5% (6/397) (2.6% difference with 95% CI 0.3% to 4.8%). For all ED discharged patients, clinically significant adverse events decreased from 0.9% (39/4,139) to 0.4% (15/3,507) (0.5% difference with 95% CI 0.1% to 0.9%). During the study, the observation rate increased 4.3% (95% CI 2.8% to 5.7%), and the admission rate increased 3.4% (95% CI 2.1% to 4.8%). CONCLUSION: A quality improvement program with feedback to physicians of telephone follow-up and resident education can decrease clinically significant adverse events in ED discharged patients.

Diagnostic Errors↗

PubMed2005

A rare case of massive pericardial effusion secondary to hypothyroidism.

Massive pericardial effusions secondary to hypothyroidism are rarely seen in the emergency department (ED). The case of a patient presenting with a relatively asymptomatic massive pericardial effusion due to hypothyroidism is described. The patient had a history of laryngeal carcinoma post-total laryngectomy and adjuvant radiotherapy 12 years previous. Although underlying malignancy was in the differential diagnosis, hypothyroidism was diagnosed through a detailed history and physical examination, thereby avoiding the need for pericardiocentesis. Thyroid replacement alone is sufficient for resolution of these effusions, although it may take many months. Pericardiocentesis is indicated only if cardiac tamponade develops. This rare but significant condition should be considered, especially when it occurs after acute cold exposure.

Aged↗

PubMed2005

Differential gene expression after hemorrhagic shock in rat lung.

BACKGROUND: We investigated the differential gene expression in rat lung after hemorrhagic shock (HS). METHODS: A controlled HS model in rats was used. Male Sprague-Dawley rats were randomly segregated into 2 groups, sham and HS. Samples of lung were procured from rats 2 hours after HS and resuscitation. Commercially available gene chips for rat cDNA microarray and software packages were used for the gene expression profile study. RESULTS: Compared with sham-shock rats, 98 genes were upregulated in HS rat lung. Most upregulated genes were responsible for inflammation (pro-inflammatory or anti-inflammatory cytokines, cognate receptors, and signal transduction for inflammation), protein activation (kinase and phosphatase), oxidation (oxidative and antioxidative enzymes), and apoptosis (apoptosis and anti-apoptosis). Eleven genes were downregulated after HS. CONCLUSION: HS may induce upregulation of positive and negative control genes responsible for inflammation, oxidation, protein metabolism and apoptosis, that is, a vulnerable period may develop in the host after HS. Overwhelming inflammatory response or immunosuppression may occur once a second hit, such as infection, ensues. Understanding, on a genome scale, how an organism responds to HS may facilitate the development of enhanced treatment modalities for HS.

Animals↗

PubMed2005

Clinical features and outcomes of severe acute respiratory syndrome and predictive factors for acute respiratory distress syndrome.

BACKGROUND: Severe acute respiratory syndrome (SARS) is an emerging infectious disease, and indeed, the SARS epidemic in Taiwan from March to July 2003 had a great impact. This study depicts the clinical characteristics and short-term outcomes of patients with SARS treated at Taipei Veterans General Hospital; potential predictive factors for acute respiratory distress syndrome (ARDS) are also analyzed. METHODS: This study retrospectively analyzed data for 67 SARS patients, who were grouped according to whether or not ARDS developed during the clinical course of SARS. RESULTS: There were 32 males (mean age, 50.3 years; range, 20-75 years) and 35 females (mean age, 51.1 years; range, 23-86 years). Twenty-five patients (37.3%) were health care workers. At admission, 50 patients (74.6%) had abnormal chest radiographs, and all patients developed pulmonary infiltrates during the following week. During hospitalization, lymphopenia was found in 57 patients (85.1%); and elevated levels of lactate dehydrogenase (LDH; n = 55; 83.3%), C-reactive protein (n = 55; 83.3%), aminotransferases (n = 44; 65.7%), and creatine kinase (n = 14; 20.9%) were also noted. ARDS developed in 33 patients (49.3%), who were generally older than the patients in whom ARDS did not develop, male, non-health care workers, and who generally had dyspnea at the time of diagnosis, and a history of diabetes mellitus, hypertension or cerebrovascular accident. Patients with, versus those without, ARDS also tended to present with more severe lymphopenia and leukocytosis, and with higher levels of LDH and aspartate aminotransferase. The overall mortality rate was 31.3% (21/67), whereas the rate for patients who developed ARDS was 63.6% (21/33). Multivariate analyses showed that age greater than 65 years (odds ratio, OR, 10.6; 95% confidence interval, CI, 2.1-54.1), pre-existing diabetes mellitus (OR, 13.7; 95% CI, 1.3-146.9), and elevated levels of LDH (OR, 8.4; 95% CI, 1.9-36.9) at admission, were independent predictors of ARDS. CONCLUSION: The clinical manifestations of SARS showed high variability, and were related to the underlying health status of individual patients. Importantly, the development of ARDS was associated with significant mortality, despite aggressive therapy.

Adult↗

PubMed2005

Internal hernia: computed tomography diagnosis and differentiation from adhesive small bowel obstruction.

BACKGROUND: The goals of this study were to evaluate the specific computed tomography (CT) features of internal hernia (IH), and to verify CT features useful for the differential diagnosis of IH from adhesive small bowel obstruction (ASBO), and for the early detection of intestinal strangulation. METHODS: CT findings for 28 patients with surgically proven IH were retrospectively reviewed and compared with those for 50 patients with surgically proven ASBO. RESULTS: CT features most suggestive of IH versus ASBO included the following: a cluster of small bowel segments (100% vs 4% of patients; p < 0.0001); crowding and convergence of mesenteric vessels (79% vs 4%; p < 0.0001); mesenteric vessel engorgement (79% vs 26%; p = 0.0002); and mass effect to the surrounding bowels (82% vs 44%; p = 0.002). In addition, intestinal strangulation, the most severe complication, occurred more in IH than ASBO (39% vs 10%; p = 0.002), whereas proximal small bowel dilation (46% vs 100%; p < 0.0001) and small-bowel feces sign (0% vs 26%; p = 0.0029) were less common in IH than ASBO. The CT features indicative of intestinal strangulation were localized mesenteric fluid (p < 0.0001), mesenteric infiltrates (p = 0.0005), bowel wall thickening (p = 0.003), intramural hemorrhage (p = 0.005), mesenteric vessel engorgement (p = 0.03), and abnormal bowel wall enhancement (p = 0.008); the first 4 of these features were noted more in patients with IH than ASBO. CONCLUSION: The most specific CT criteria for the diagnosis of IH, rather than ASBO, were engorged mesenteric vessels, mass effect to surrounding organs, and bowel wall thickening. When associated mesenteric infiltrates were found, intestinal strangulation was highly suspected.

Abdomen↗

PubMed2005

Impact of severe acute respiratory syndrome (SARS) outbreaks on the use of emergency department medical resources.

BACKGROUND: The impact of the severe acute respiratory syndrome (SARS) outbreak in 2003 on the emergency department (ED) medical needs of adult patients has not been elucidated. The purpose of this study was to investigate the demographic and clinical characteristics of ED adult patients before, during and after the SARS epidemic in a SARS-dedicated hospital. METHODS: A retrospective, ED chart review was conducted, and demographic data were obtained from a computer database, for a total of 17,586 patients. Patient information, including age, gender, mode of arrival, triage category, time of visit, main diagnosis, use of ED services, and status after the ED visit, were collected and compared for pre-, early-, peak-, late-, and post-SARS epidemic stages. RESULTS: Demographic data demonstrated a significant decrease in patient attendances per day, with a mean reduction of 92.5 +/- 8.3 patients (43.7 +/- 3.9% reduction in rate; p < 0.01) during peak- versus pre-epidemic stages, but revealed no differences in patient age and gender. The numbers of patients with ambulance transport, inter-hospital referral, and critical illnesses, including DOA, categorized as triage 1, or admitted to a ward or intensive care unit after the ED visit, were not influenced by the SARS epidemic. The number of patients with upper airway infections and suicide attempts from drug overdoses increased, but not statistically significantly. The number of patients with other diagnoses decreased progressively from early- to peak-epidemic stages, but returned to their earlier levels at the post-epidemic stage. Statistically significant decreases (p < 0.05) were noted in mean attendance at peak-versus pre- and early-epidemic stages for patients with cardiovascular disease, inflammatory or functional bowel disease, endocrine disease, dizziness or vertigo, or trauma. CONCLUSION: The SARS outbreak did not eliminate the need of critically ill patients for advanced medical support. However, besides an overall decrease in patient numbers, the SARS epidemic markedly altered demographic information, clinical characteristics, and the use of medical services by adult patients in the ED of a SARS-dedicated hospital.

Adult↗

PubMed2005

Differentiating colonic diverticulitis from colon cancer: the value of computed tomography in the emergency setting.

BACKGROUND: The purpose of this study was to establish practical diagnostic criteria to differentiate colonic diverticulitis from colon cancer by computed tomography (CT) in the emergency department (ER). METHODS: Helical CT scans of 40 patients admitted to the ER with the clinical diagnosis of diverticulitis and 14 patients diagnosed with colon cancer were retrospectively reviewed. In total, 18 imaging parameters were analyzed and were compared between the 2 groups of patients. RESULTS: Thirteen parameters were found to be statistically significant for the diagnosis of colonic diverticulitis in excluding colon cancer: pericolic infiltration (p < 0.001); presence of lymph nodes (p < 0.001); inflamed diverticula (p = 0.001); non-inflamed diverticula (p = 0.001); degree of enhancement (p = 0.001); intestinal obstruction (p = 0.001); involved wall thickness (p = 0.005); lymph node size (p = 0.007); fascial thickening (p = 0.009); pattern of enhancement (p = 0.012); involved length (p = 0.014); free air (p = 0.035); and abscess formation (p = 0.042). Among these parameters, the most valuable imaging findings for diverticulitis were the presence of non-inflamed diverticulum, inflamed diverticulum, mild degree of enhancement, and small lymph node size. Three were found to have high specificity but low sensitivity: target enhancement pattern; abscess formation; and free air. When colonic obstruction is present, colon cancer is more likely than diverticulitis. CONCLUSION: Specific CT criteria help to differentiate colonic diverticulitis from colon cancer. CT scan with intravenous contrast administration would be the best noninvasive imaging modality in the ER for the accurate diagnosis and appropriate management of such disease.

Adult↗

PubMed2005

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, Cl, 1.013, 1.146; p = 0.02); bandemia (OR, 3.894; 95% Cl, 1.160, 13.074; p = 0.03); elevated serum aspartate aminotransferase (AST; OR, 4.532; 95% Cl, 1.274, 16.122; p = 0.02); increased blood urea nitrogen (BUN; OR, 7.219; 95% Cl, 1.166, 44.696; p = 0.03); and metabolic acidosis (OR, 6.604; 95% Cl, 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.

Acute Disease↗

PubMed2005

The role of diagnostic algorithms in the management of blunt splenic injury.

BACKGROUND: Diagnostic algorithms for patients with blunt abdominal trauma have been in use since 1995. This study investigated the role of diagnostic algorithms in the management of adult patients with blunt splenic injury at our institution. METHODS: A retrospective review of hospital records was performed to enroll patients with blunt injury of the spleen. Demographic data and information about injury severity, diagnostic methods, management and final outcomes were evaluated. Patients were separated into an early and late group according to the year that diagnostic algorithms were used (1990-1994 or 1995-1999). RESULTS: One hundred and twenty-one patients were enrolled. Initially, 71 patients had an operation (OP group), whereas 50 received non-operative management (NOM group). Patients in the OP versus NOM group had lower blood pressure and greater transfusion volumes in the emergency room, higher grade splenic injury, and a greater rate of intra-abdominal-related injury. NOM failed in 7 patients (14%). Early- versus late-group patients were less likely to have NOM and high grade splenic injury; however, the rate of NOM failure was not different between the early and late groups. CONCLUSION: Diagnostic algorithms using sonograms for screening provide an initial means of selecting patients for NOM. Patients with higher grades of splenic injury can then be managed non-operatively.

Adolescent↗

PubMed2005

Rapid brain cooling by hypothermic retrograde jugular vein flush.

BACKGROUND: Although whole-body hypothermia recently has been reported effective in improving the neurologic outcome after cardiac arrest, it is contraindicated in the management of trauma patients with hemorrhagic shock. To provide selective brain cooling in this situation, the authors speculated about the feasibility of hypothermic retrograde jugular vein flush (HRJVF). This preliminary study was conducted to test the effectiveness of brain cooling after HRJVF in rats without hemorrhagic shock. METHODS: After jugular vein cannulation with cranial direction, Sprague-Dawley rats were randomized into a normal control group, a group that underwent flush with cold saline at 4 degrees C, or a group that underwent flush with saline at a room temperature of 24 degrees C. A Servo-controlled heat lamp was applied for all the rats to keep their rectal temperature at 37 +/- 0.5 degrees C. Their brain temperature and cerebral blood flow were checked. RESULTS: Within the 10-minute period of cold saline flush (1.7 mL/100 g), brain temperature was immediately decreased, and this cooling effect could be maintained for at least 20 minutes. Cerebral blood flow was significantly increased after HRJVF, then returned gradually to the baseline as brain temperature elevated. CONCLUSIONS: This study successfully demonstrated a significant cooling effect in rat brain by HRJVF. For preservation of brain function, HRJVF may be useful in resuscitation for trauma patients with hemorrhagic shock after further studies on animals with shock.

Animals↗

PubMed2005

Characteristics of thyroidectomy in Taiwan.

BACKGROUND AND PURPOSE: Thyroidectomy is a common treatment for thyroid disorders in Taiwan, and constitutes a significant percentage of medical expenses. This study investigated the characteristics of thyroidectomy in Taiwan. METHODS: A total of 21 senior general surgeons from 16 medical centers and 5 regional hospitals participated. One surgeon from each hospital reviewed the hospital's medical records of thyroid operations performed in the year 2001. Medical records for 3846 thyroidectomies were retrospectively analyzed, including surgical indications and modalities, complications, pathology reports, and the use of antibiotics. RESULTS: Most of the patients were women (85%). Indications for surgery included proven malignancy (9%), suspicious malignancy (30%), evident compression symptoms (20%), hyperthyroidism (20%), and cosmetic reasons (12%). The majority of patients (78%) underwent a surgical procedure with lobectomy or bilateral thyroidectomy; 13% had unilateral partial thyroidectomy. Prophylactic antibiotics were administered in 46% of procedures, and continued postoperatively in 12%. Postoperative complications occurred in 12% of patients. Hypocalcemia was the most common complication (8%), and its incidence was significantly correlated with the frequency of total thyroidectomy (p < 0.01). Complete pathology reports for the thyroidectomized specimens were available in only 65% of the cases. The frequency of cosmetic reasons for surgery, unilateral subtotal resection, routine antibiotic administration, and incomplete pathology reports were significantly higher in regional hospitals than in medical centers. CONCLUSIONS: Reduction in the high rates of cosmetic reasons for surgery, unilateral partial thyroidectomy, incomplete pathology reports, and use of antibiotic prophylaxis are needed to improve the quality of thyroidectomy in Taiwan.

Adolescent↗

PubMed2004

ED presentation of neutropenic enterocolitis in adult patients with acute leukemia.

The purpose of this study was to investigate the initial clinical features and subsequent outcomes in patients with adult leukemia with typhlitis or neutropenic enterocolitis. A retrospective review of 10 episodes of neutropenic enterocolitis in nine patients (age range, 21-71 years) with acute leukemia from March 1, 1990, through February 28, 2002, was conducted. In clinical presentations, fever appears in all patients, followed by abdominal pain or tenderness (90%) and diarrhea (60%), respectively. In particular, three cases were coincidentally diagnosed as leukemia before any chemotherapy. The most common diagnostic modality used for the diagnosis of neutropenic enterocolitis was computed tomography (CT) scan (seven episodes). Medical treatments, including broad-spectrum antibiotics, bowel rest, and total parenteral nutrition, were applied to seven patients. Laparotomy with bowel resection was performed on two patients with bowel necrosis and severe peritonitis. Of all nine cases, six were fatal as a result of sepsis, a common complication of neutropenic enterocolitis. As the incidence of neutropenic enterocolitis increases in patients with acute leukemia, EPs should be alert and make an early diagnosis of this rapidly deteriorated and life-threatening disease.

Adult↗

PubMed2004

Hepatic portal venous gas: clinical significance of computed tomography findings.

Hepatic portal venous gas (HPVG) is a rare radiographic finding of significance. Most cases with HPVG are related to mesenteric ischemia that have been associated with extended bowel necrosis and fatal outcome. With the help of computed tomography (CT) in early diagnosis of HPVG, the clinical outcome of patients with mesenteric ischemia has improved. There has been also an increasing rate of detection of HPVG with certain nonischemic conditions. In this report, we present two cases demonstrating HPVG unrelated to mesenteric ischemia. One patient with cholangitis presented abdominal pain with local peritonitis and survived after appropriate antibiotic treatment. Laparotomy was avoided as a result of lack of CT evidence of ischemic bowel disease besides the presence of HPVG. The other case had severe enteritis. Although his CT finding preluded ischemic bowel disease, conservative treatment was implemented because of the absence of peritoneal signs or clinical toxic symptoms. Therefore, whenever HPVG is detected on CT, urgent exploratory laparotomy is only mandatory in a patient with whom intestinal ischemia or infarction is suspected on the basis of radiologic and clinical findings. On the other hand, unnecessary exploratory laparotomy should be avoided in nonischemic conditions that are usually associated with a better clinical outcome if appropriate therapy is prompted for the underlying diseases. Patients with radiographic diagnosis of HPVG should receive a detailed history review and physical examination. The patient's underlying condition should be determined to provide a solid ground for exploratory laparotomy. A flow chart is presented for facilitating the management of patients with HPVG in the ED.

Aged↗

PubMed2004

A simple, safe, and efficient way to treat severe fluoride poisoning--oral calcium or magnesium.

PURPOSE: To examine the efficacy and safety of administration of calcium and magnesium orally and intraperitoneally to treat severe sodium fluoride intoxication. MATERIALS AND METHODS: Mice were initially gavaged a lethal dose of sodium fluoride (NaF) or water. Then, mice were treated with water or varying concentrations of calcium chloride (CaCl2) or magnesium sulfate (MgSO4) via intraperitoneal (IP) route or via oral route. Mice were monitored for 24 h, and the time of death was recorded. RESULTS: IP injections of large amounts of CaCl2 or MgSO4 were dangerous. All mice gavaged with water and then treated with oral CaCl2 or MgSO4 survived and displayed normal activity during the experiment. The survival rate of mice gavaged with a lethal dose of NaF and then treated with a high dose of oral CaCl2 or MgSO4 was significantly higher than those of using low dose. CONCLUSION: Oral administration of a high dose of CaCl2 or MgSO4 is a simple, safe, and effective adjunctive method for treating severe oral fluoride poisoning.

Administration, Oral↗

PubMed2004

Rapid creation of a temporary isolation ward for patients with severe acute respiratory syndrome in Taiwan.

OBJECTIVES: To rapidly establish a temporary isolation ward to handle an unexpected sudden outbreak of severe acute respiratory syndrome (SARS) and to evaluate the implementation of exposure control measures by healthcare workers (HCWs) for SARS patients. DESIGN: Rapid creation of 60 relatively negative pressure isolation rooms for 196 suspected SARS patients transferred from 19 hospitals and daily temperature recordings of 180 volunteer HCWs from 6 medical centers. SETTING: A military hospital. RESULTS: Of the 196 patients, 34 (17.3%) met the World Health Organization criteria for probable SARS with positive results of serologic testing for SARS-associated coronavirus (SARS-CoV), reverse transcriptase polymerase chain reaction (RT-PCR) from nasopharyngeal or throat swabs for SARS-CoV, or both. Seventy-four patients had suspected SARS based on unprotected exposure to SARS patients; three of them had positive results on RT-PCR but negative serologic results. The remaining 88 patients did not meet the criteria for a probable or suspected SARS diagnosis. Of the 34 patients with probable SARS, 13 were transferred to medical centers to receive mechanical ventilation due to rapid deterioration of chest x-ray results, and three patients died of SARS despite intensive therapy in medical centers. During the study period, one nurse developed probable SARS due to violation of infection control measures, but there was no evidence of cross-transmission to other HCWs. CONCLUSIONS: Despite the use of full personal protection equipment, the facility failed to totally prevent exposures of HCWs to SARS but minimized the risk of nosocomial transmission. Better training and improvements in infection control infrastructure may limit the impact of SARS.

Disease Outbreaks↗

PubMed2004

Hypothermic retrograde jugular vein flush in heatstroke rats provides brain protection by maintaining cerebral blood flow but not by hemodilution.

OBJECTIVE: To determine the fundamental mechanism of brain protection by hypothermic retrograde jugular vein flush (HRJVF) in heatstroke rats. DESIGN: Randomized, controlled, and prospective study. SETTING: University physiology research laboratory. SUBJECTS: Sprague-Dawley rats (270-320 g, males). INTERVENTIONS: Rats were randomized into four groups as follows: a) normothermic control (NC, n = 8); b) heatstroke rats without cold saline delivery (HS, n = 8); c) heatstroke rats treated with cold saline via femoral vein (HS+F, n = 8); and d) heatstroke rats treated with HRJVF (HS+J, n = 8). Right external jugular vein and right femoral vein were cannulated in each rat. The cannulation in the jugular vein was with cranial direction. To produce heatstroke, rats were placed in a chamber with an ambient temperature of 43 degrees C. The cold saline (4 degrees C, 1.7 mL/100 g) was delivered via the cannula in either the femoral vein or jugular vein immediately after the onset of heatstroke. Glutamate release in the brain, cerebral blood flow (CBF), and hematocrit of arterial blood were determined. MEASUREMENTS AND MAIN RESULTS: After onset of heatstroke, HRJVF significantly decreased the glutamate release. In contrast, cold saline delivery via femoral vein could only delay the elevation of glutamate release in the brain. The CBF of HS and HS+F rats decreased rapidly after the onset of heatstroke, but the CBF of HS+J rats was initially elevated by HRJVF and was maintained at baseline 30 mins after onset of heatstroke. Hematocrit in all the rats did not change after testing. CONCLUSIONS: HRJVF protects the brain by maintaining cerebral blood flow in rats after heatstroke. To preserve brain function and prolong survival after severe heatstroke, maintenance of cerebral blood flow is important in the management of heatstroke.

Animals↗