Chip-Jin Ng

Mortality after successful transcatheter arterial embolization in patients with unstable pelvic fractures : Rate of blood transfusion as a predictive factor

BACKGROUND To determine the factors predictive of mortality in patients with unstable pelvic fractures after successful transcatheter arterial embolization. METHODS A retrospective study of pelvic fractures between May of 1995 and April of 1998 was performed. Of 507 patients, 17 who were unstable underwent embolization. The success rate of embolization and the mortality rate after successful embolization were reviewed. Predictive factors (contrast medium extravasation, initial blood pressure, Injury Severity Score, timing of external fixation, time to angiography, volume of blood transfusion, rate of blood transfusion) of the final outcome were statistically analyzed. RESULTS Embolization was 100% effective in stopping pelvic hemorrhage. The mortality of patients treated successfully with embolization was 17.6%. Among the predictive factors analyzed, only the rate of blood transfusion before embolization, 11.3 +/- 11.0 units/h (death) versus 3.2 +/- 1.9 units/h (survival) showed statistical significance with an odds ratio of 1.62 (95% confidence interval, 1.07-2.46). CONCLUSION The success rate of embolization was 100% in stopping arterial hemorrhage of unstable pelvic fractures. The survival rate after successful embolization was 82.4%. Patients who had rapid blood transfusion before embolization had a poor final outcome. The risk of dying increased by 62% for every 1 unit/h increase of transfusion rate.

Deep venous thrombosis: comparison of indirect multidetector CT venography and sonography of lower extremities in 26 patients.

OBJECTIVE To compare the accuracy of indirect mutidetector row computed tomographic (MDCT) venography with lower extremity venous sonography for the diagnosis of femoropopliteal deep venous thrombosis (DVT), and to determine the frequency and location of DVT at MDCT venography. MATERIALS AND METHODS Twenty-six consecutive patients suspected of having pulmonary embolism (PE) underwent both combined MDCT venography and MDCT pulmonary angiography and lower extremity venous sonography. Indirect MDCT venography was acquired from the upper calves to the mid-abdomen following MDCT pulmonary angiography. The CT venographic findings were compared with those of sonography for the diagnosis of femoropopliteal DVT. All CT scans were also reviewed for the frequency and location of DVT. RESULTS Indirect MDCT venography disclosed DVT in 19 patients, and 12 of whom also had PE. Seventeen patients with thrombosis in the femoropopliteal veins were identified in both indirect MDCT venography and sonography. The sensitivity and specificity of indirect MDCT venography for femoropopliteal DVT, as compared with sonography, were both 100%. In one patient DVT in the superficial femoral vein was detected using only indirect MDCT venography. MDCT venography also showed superior extension of femoropopliteal DVT to the inferior vena cava and iliac veins in four patients and thrombosis isolated to the inferior vena cava and common iliac vein thrombosis in one patient. CONCLUSIONS Indirect MDCT venography is as accurate as sonography in the diagnosis of femoropopliteal DVT. MDCT venography can further reveal thrombus in large pelvis veins and the inferior vena cava, an important advantage over sonographic screening for DVT.

Validation of the Taiwan triage and acuity scale: a new computerised five-level triage system

Objective An ideal emergency department (ED) triage system accurately prioritises patients on the basis of the urgency of interventions required to avoid under- or over-triage. The objective of this study was to develop and validate a five-level Taiwan triage and acuity scale (TTAS) with an electronic decision support tool. Methods This prospective, multicentre, observational study included 10533 patients triaged at 11 academic medical centres, 18 regional and four district hospitals. Adult patients presenting to the ED were independently triaged by the duty triage nurse in the usual way and trained research nurses using TTAS with a computerised decision support system. Weighted κ statistics were used to assess the reproducibility. Hospitalisation, length of stay, and medical resource consumption were analysed by TTAS acuity levels. Results Most cases were stratified into levels 2 to 3 by the existing four-level triage system, whereas the TTAS stratified most patients to levels 3 (41.4%) and 4 (25.0%), and only a small number to level 1 (3.9%) (resuscitation; most urgent). Weighted κ for TTAS assignment was 0.87 (95% CI 0.85 to 0.89). The decrease in mean medical resource consumption and hospitalisation rate was statistically significant with each decrease in the TTAS triage acuity level. The length of stay also decreased significantly as the TTAS level acuity fell from levels 2 to 5. Conclusions The TTAS was found to be a reliable triage system that accurately prioritises the treatment needed to avoid overtriage, more efficiently deploying the appropriate resources to ED patients.

Diagnosis of acute flank pain caused by ureteral stones: value of combined direct and indirect signs on IVU and unenhanced helical CT

The aim of this study was to assess the usefulness of combined direct and indirect signs on intravenous urography (IVU) and unenhanced helical computed tomography (UHCT) for the diagnosis of ureteral stones in emergency patients with acute flank pain. During an 8-month period, 82 emergency patients with acute flank pain undergoing IVU and UHCT with sufficient clinical follow-up formed the study group. The presence or absence of direct sign (visualization of ureteral stones) and indirect signs on IVU and UHCT was recorded. The diagnostic accuracy of each direct/indirect sign and their combination for the diagnosis of ureteral stones on IVU and UHCT were analyzed and compared. Of the 82 patients, 66 had ureteral stones, four had passed urinary stones prior to imaging and 12 had other diseases. The diagnostic accuracies of direct signs on IVU and UHCT for the diagnosis of ureteral stones were 79.3 and 98.8%, respectively, which was more accurate than that of any single indirect sign on IVU and UHCT. However, the diagnostic accuracy of ureteral stones by IVU increased to 90.2% when using diagnostic criteria requiring the presence of a direct sign or at least three indirect signs, and by UHCT, it increased to 100% when using diagnostic criteria requiring the presence of a direct sign with at least one indirect sign. Therefore, for emergency patients with acute flank pain, the use of the above combinations of direct/indirect signs is useful as the diagnostic criterion for ureteral stones.

Comparison Between Canadian Triage and Acuity Scale and Taiwan Triage System in Emergency Departments

BACKGROUND/PURPOSE Since the implementation of National Health Insurance in Taiwan, Emergency Department (ED) volume has progressively increased, and the current triage system is insufficient and needs modification. This study compared the prioritization and resource utilization differences between the four-level Taiwan Triage System (TTS) and the standardized five-level Canadian Triage and Acuity Scale (CTAS) among ED patients. METHODS This was a prospective observational study. All adult ED patients who presented to three different medical centers during the study period were included. Patients were independently triaged by the duty triage nurse using TTS, and a single trained research nurse using CTAS with a computer support software system. Hospitalization, length of stay (LOS), and medical resource consumption were analyzed by comparing TTS and CTAS by acuity levels. RESULTS There was significant disparity in patient prioritization between TTS and CTAS among the 1851 enrolled patients. With TTS, 7.8%, 46.1%, 45.9% and 0.2% were assigned to levels 1, 2, 3, and 4, respectively. With CTAS, 3.5%, 24.4%, 44.3%, 22.4% and 5.5% were assigned to levels 1, 2, 3, 4, and 5, respectively. The hospitalization rate, LOS, and medical resource consumption differed significantly between the two triage systems and correlated better with CTAS. CONCLUSION CTAS provided better discrimination for ED patient triage, and also showed greater validity when predicting hospitalization, LOS, and medical resource consumption. An accurate five-level triage scale appeared superior in predicting patient acuity and resource utilization.

Altered neutrophil apoptosis activity is reversed by melatonin in liver ischemia-reperfusion.

Delayed neutrophil apoptosis has been implicated as the mechanism of the systemic inflammatory response. Herein, we examined the effect of melatonin on the neutrophil apoptosis in ischemia and reperfusion of the human liver. We studied seven patients receiving elective hepatectomy for liver tumor and ten patients receiving laparoscopic cholecystectomy for gallstones. Ten milli liters of blood was drawn isolation and incubation of the human neutrophils. Neutrophil apoptosis activity and CD18 expression and respiratory burst activity were assessed flow cytometrically. Another group of neutrophils included those from the patients receiving hepatectomy and isolated and incubated with melatonin. Neutrophil apoptosis is delayed from patients after hepatectomy or laparoscopic cholecystectomy when compared with that of the preoperative state. The decrease in the apoptosis activity is more severe in patients receiving hepatectomy as compared with those receiving laparoscopic cholecystectomy. Neutrophils from patients receiving hepatectomy or laparoscopic cholecystectomy are functionally activated. Melatonin can reverse the delayed process and enhance the apoptosis activity in neutrophils from patients receiving hepatectomy. This study demonstrates that melatonin enhances neutrophil apoptosis in patients receiving hepatectomy involving ischemia and reperfusion of the human liver.

Rapid Life-Threatening Hyperkalemia After Addition of Amiloride HC1/Hydrochlorothiazide to Angiotensin-Converting Enzyme Inhibitor Therapy

STUDY OBJECTIVE To highlight the dangers of a precipitous rise in serum potassium levels in patients at risk for renal insufficiency, already receiving an angiotensin-converting enzyme (ACE) inhibitor, who are given a potassium-sparing diuretic. METHODS We conducted a retrospective chart review of five patients who were taking the above combination of medications who were seen in our ED with hyperkalemia. RESULTS All five patients had diabetes and were older than 50 years of age. Except for one patient, they had some degree of renal impairment and all were receiving an ACE inhibitor. Each had amiloride HCl/hydrochlorothiazide added to their therapeutic regimen 8 to 18 days before presenting to our ED with hyperkalemia. Potassium levels were between 9.4 and 11 mEq/L in 4 of the patients; 2 did not respond to resuscitation measures. CONCLUSION The concomitant use of ACE inhibitor and potassium-sparing diuretic therapy should be avoided. If impossible, weekly monitoring of both renal function and serum potassium should be performed. In the ED patients who are receiving such a combination should receive immediate ECG monitoring.

Risk of immediate effects from F(ab)2 bivalent antivenin in Taiwan.

OBJECTIVE To evaluate the incidence of immediate adverse effects from equine fragment antigen binding F(ab)2 bivalent antivenin produced by the National Institute of Preventive Medicine (NIPM) in Taiwan. METHODS A retrospective chart review of patients presenting to a 600-bed general hospital over a 3-year period with snakebite who were treated with NIPM antivenin. RESULTS A total of 130 snakebite victims presented to the emergency department over the study period, and 159 vials of antivenin were given. One hundred two patients (78.5%; 95% CI: 70, 85) received only hemorrhagic bivalent antivenin, 2 (1.5%; 95% CI: 0, 5) received only neurotoxic bivalent antivenin, and the remaining 26 (20.0%; 95% CI: 13, 28) received both kinds of bivalent antivenin. Three received a second vial of hemorrhagic antivenin because of progression of symptoms. Forty-two patients (32.3%; 95% CI: 24, 41) had positive skin tests, but following pretreatment with diphenhydramine and hydrocortisone, only 1 patient developed a skin rash thought to be related to antivenin. No patient developed an anaphylactic reaction. CONCLUSIONS The use of NIPM F(ab)2 antivenin in snakebite victims in Taiwan has a very low risk of acute adverse reactions.

Melatonin reduces pancreatic prostaglandins production and protects against caerulein-induced pancreatitis in rats

Abstract:  Melatonin has been used to treat experimental pancreatitis, although not all the drugs therapeutic mechanisms of melatonin have been defined. Prostaglandins (PGs) are proinflammatory mediators that exert their effects mainly locally during inflammatory diseases. The present study was undertaken to examine whether treatment with melatonin influences local PG production. An acute pancreatitis model in male Sprague–Dawley rats (225–275 g) was established by continuously infusing caerulein (15 mg/kg/hr). Mean arterial pressure and pancreatic perfusion were monitored continuously. Melatonin was delivered via the intraperitoneal route at doses of either 2 or 10 mg/kg, 30 min after caerulein injection. Malondialdehyde and glutathione levels of the pancreas and liver and the trypsinogen activation peptide levels in the serum were measured at the end of the experiment (8 hr after infusion of caerulein). Intraperitoneal injection of melatonin (2 and 10 mg/kg) reduced the reduction in systemic arterial pressure and decreased pancreatic perfusion in the rat model of caerulein pancreatitis. Moreover, melatonin treatment changed local PG production toward control level. Higher dose of melatonin was somewhat more effective in preventing the caerulein‐induced alterations than was the lower dose.

Delayed Neutrophil Apoptosis Attenuated by Melatonin in Human Acute Pancreatitis

Objectives: This study evaluated the expression of neutrophil apoptosis and the effects of melatonin at different concentrations on delayed neutrophil apoptosis in different severities of acute pancreatitis in patients. Methods: The study population was comprised of 10 patients with severe acute pancreatitis (SAP) and 10 with mild acute pancreatitis (MAP). A total of 10 mL of blood was drawn 24 hours after the onset of the clinical disease for isolation and incubation of the human neutrophils with 4 different concentrations of melatonin. Neutrophil apoptosis activity, CD18 expression, and respiratory burst activity were assessed with flow cytometry 12 hours after incubation. Another group of neutrophils from a healthy control group was used (n = 6) for comparison. Results: Neutrophil apoptosis in patients with SAP is delayed compared with that of patients with MAP. Neutrophils from patients with SAP or MAP are functionally activated. Melatonin at concentrations of 10−8, 10−7, or 10−6 M reverses the delayed process and enhances apoptosis activity in neutrophils in patients with MAP. Melatonin at concentrations of 10−7 and 10−6 M reverses the delayed process and increases apoptosis activity in neutrophils in patients with SAP. Neutrophils from patients with SAP and MAP showed significantly increased CD18 expression and respiratory burst activity. Melatonin at concentrations of 10−7 or 10−6 M reverses CD18 expression and respiratory burst activity in neutrophils in patients with SAP. Conclusions: This study highlights the importance of neutrophil apoptosis in patients with SAP and raises the possibility of a therapeutic strategy. Study data show that melatonin promotes neutrophil apoptosis in human acute pancreatitis.