A Case of Levofloxacin-Induced Anaphylaxis With Elevated Serum Tryptase Levels

Levofloxacin, a fluoroquinolone and L-isomer of the racemate ofloxacin, has been approved for the treatment of acute and chronic bacterial infections. Gastrointestinal complaints are the most frequently reported adverse drug reactions to fluoroquinolones. Other adverse events include headache, dizziness, increased liver enzyme levels, photosensitivity, tachycardia, QT prolongation, and eruptions. Anaphylaxis has been documented as a rare adverse drug reaction to levofloxacin; however, diagnostic tests are needed to evaluate whether these reactions are the result of levofloxacin treatment. While the results of skin tests are considered unreliable due to false-positive responses, the oral provocation test is currently considered to be the most reliable test. Tryptase, a neutral protease, is the dominant protein component of secretory granules in human mast cells, and an increased serum concentration of tryptase is a highly sensitive indicator of anaphylaxis. Herein, we report a case of levofloxacin-induced anaphylaxis in which the patient exhibited elevated serum tryptase levels and a positive oral levofloxacin challenge test result. As anaphylaxis is potentially life-threatening, the administration of fluoroquinolones to patients who have experienced a prior reaction to this type of agent should be avoided.

Occupational asthma caused by inhaling smoke from roasting perilla seeds

Perilla is an Asian grain that consumed for food ingredient, oil crops, medicinal materials through the process of roasting. A 49-year-old male has been roasting grains for 10 years, who met with shortness of breath during the roasting perilla seeds, but not in other situations. Serum total immunoglobulin E (IgE) level, serum eosinophil count and skin prick test didn't showed significant results. Methacholine bronchial provocation test was positive (PC20 0.31 mg/mL). Specific bronchial provocation test with inhaling smoke from roasting perilla seeds showed a dual asthmatic response. Measured peak expiratory flow rate on his work place showed the result of 37% decrease at the end of work and full recovery at 6 hours after the end of work. Skin prick test to row perilla showed positive response with late symptoms. We diagnosed that the patient had an occupational asthma caused by inhaling smoke from roasting perilla seeds with IgE mediated mechanism.

Risk Factors Related with Mortality in Patient with Pulmonary Tuberculosis / 결핵및호흡기질환

BACKGROUND: The prevalence rate of pulmonary tuberculosis (PTB) is steadily decreasing in South Korea. However, PTB is a disease with relatively high mortality and morbidity rates throughout Korea. Although there are many studies and statistics about the risk factors of PTB mortality in many countries, there are only a limited number of domestic papers on this topic. The aim of this study is to determine predictive factors for mortality among in-hospital patients associated with PTB. METHODS: From December 2006 to January 2011, we reviewed medical records of 2,122 adult patients diagnosed with tuberculosis at a single tertiary hospital in a suburban area. In this study period, 960 patients were diagnosed with PTB by positive Acid fast bacilli smear and/or mycobacterial culture of the respiratory specimen. We compared the groups of patients deceased and patients discharged alive with PTB. The number of dead patients was 82 (47 males, 35 females). RESULTS: Mortality was significantly associated with increased values of white blood cells (WBC), blood urine nitrogen (BUN), creatinine, C-reactive protein (CRP), numbers of involved lung field, and length of hospitalization. Also, it was associated with the decreased values of hemoglobin, lymphocyte, sodium, albumin, and cholesterol. Furthermore, admission through the emergency department, initial intensive care unit admission, and drug resistant PTB affected mortality in PTB patients. Independent predictors associated with PTB mortality are BUN, initial intensive care unit care, and admission during treatment of tuberculosis. CONCLUSION: In our study, mortality of pulmonary tuberculosis was related with parameters associated with nutritional status, disease severity at the time of admission, and drug resistance.

Risk Factors Related with Mortality in Patient with Pulmonary Tuberculosis / 결핵및호흡기질환

BACKGROUND: The prevalence rate of pulmonary tuberculosis (PTB) is steadily decreasing in South Korea. However, PTB is a disease with relatively high mortality and morbidity rates throughout Korea. Although there are many studies and statistics about the risk factors of PTB mortality in many countries, there are only a limited number of domestic papers on this topic. The aim of this study is to determine predictive factors for mortality among in-hospital patients associated with PTB. METHODS: From December 2006 to January 2011, we reviewed medical records of 2,122 adult patients diagnosed with tuberculosis at a single tertiary hospital in a suburban area. In this study period, 960 patients were diagnosed with PTB by positive Acid fast bacilli smear and/or mycobacterial culture of the respiratory specimen. We compared the groups of patients deceased and patients discharged alive with PTB. The number of dead patients was 82 (47 males, 35 females). RESULTS: Mortality was significantly associated with increased values of white blood cells (WBC), blood urine nitrogen (BUN), creatinine, C-reactive protein (CRP), numbers of involved lung field, and length of hospitalization. Also, it was associated with the decreased values of hemoglobin, lymphocyte, sodium, albumin, and cholesterol. Furthermore, admission through the emergency department, initial intensive care unit admission, and drug resistant PTB affected mortality in PTB patients. Independent predictors associated with PTB mortality are BUN, initial intensive care unit care, and admission during treatment of tuberculosis. CONCLUSION: In our study, mortality of pulmonary tuberculosis was related with parameters associated with nutritional status, disease severity at the time of admission, and drug resistance.

A Case of Hereditary Hemorrhagic Telangiectasia Diagnosed through Spontaneous Hemothorax / 결핵및호흡기질환

Hereditary hemorrhagic telangiectasia (HHT, Osler-Weber-Rendu disease) is a rare autosomal dominant disease characterized by heterogenous multisystemic dysplasia of the vascular tissue. Prevalence of HHT is 1 in 5,000~8,000. HHT commonly presents with recurrent epistaxis, but may have more serious consequences if visceral vascular beds are involved. Approximately 30~50% of HHT cases also present with pulmonary arteriovenous malformation (PAVM). Spontaneous hemothorax is less common, and PAVM is one of the causes leading to hemothorax. Our case involved an 18-year-old female who had suddenly developed right chest pain. The reason for chest pain was due to right spontaneous hemothorax accompanied by PAVM in the right middle lobe. The patient was additionally diagnosed with HHT upon examination of her family history, specifically through her mother's symptom that included recurrent epistaxis and mucosal telangiectasia.

The Efficacy of Immediate Diet for Reducing Local Adverse Events of Inhaled Corticosteroid: A Pilot Study / 결핵및호흡기질환

BACKGROUND: Local adverse events associated with inhaled corticosteroid use, including dysphonia, pharyngitis and oral candidiasis, can affect adherence for treatment. 'Mouth rinsing method' has been used for reducing local adverse events, but it cannot ensure complete prevention. The goal of this pilot study was to identify whether the 'immediate diet method' can reduce local adverse events in a limited number of patients. METHODS: The study was conducted in a total of 98 patients, who had been prescribed a medium-dose fluticasone propionate for the first time, from January to October in 2010. One training nurse had performed the education on how to use the inhaler, including the mouth rinsing method. And with follow-ups at one month intervals, any patient who experienced such adverse events were educated on the immediate diet method, having a meal within 5 minutes after using an inhaler and they were checked on any incurrence of adverse events with one month intervals for 2 months. RESULTS: The mean age of patients was 65.9 years old. The local adverse events had incurred from 18.4% of the study subjects. When performed the follow-up observation in 18 patients with local adverse events after education on the immediate diet method, 14 patients (77.8%) had shown symptomatic improvements. Three of 4 patients did not show any improvement, in spite of implementing the immediate diet method. The other 1 patient did not practice the immediate diet method properly. CONCLUSION: The immediate diet method may be useful in reducing the local adverse events, caused by the use of inhaled corticosteroid.

A Case of Radiation Bronchitis Induced Massive Hemoptysis after High-Dose-Rate Endobronchial Brachytherapy / 결핵및호흡기질환

High-dose-rate endobronchial brachytherapy (HDREB) have been used as the treatment of early endobronchial cancer, as well as for palliation of advanced cancer. However, fatal hemoptysis can occur after HDREB at the rate of 7~32%. We report a case of massive hemoptysis due to radiation bronchitis developed after HDREB. A 67-year-old man was treated with HDREB for early endobronchial cancer on the left upper lobe bronchus. He complained of persistent cough from 4 weeks after completion of HDREB. Radiation bronchitis was observed on the bronchoscopy at 34 weeks, and it was progressed from mucosal swelling and exudate formation to necrosis and ulceration without local relapse. In addition, he died of massive hemoptysis after 15 months. The patient had no sign or radiologic evidences to predict the hemoptysis. This case implies that HDREB directly contributes to an occurrence of a fatal hemoptysis, and follow-up bronchoscopy is important to predict a progression of radiation bronchitis and fatal hemoptysis.

2 Cases of Mycoplasma pneumoniae Infection with Severe Pneumonia / 결핵및호흡기질환

Mycoplasma pneumoniae (M. pneumoniae) is the leading cause of pneumonia in older children and young adults. Normally, it does not progress to a condition requiring hospitalization but improves spontaneously or has a mild clinical course. We report two cases of M. pneumoniae pneumonia with different clinical manifestations from the normal course. The patients were young healthy individuals. The diagnoses were made by serology. However, it could not be determined beforehand that they had M. pneumoniae pneumonia. Based on the empirical treatment strategy of severe community acquired pneumonia, the patients were treated with broad-spectrum antibiotics including cephalosporin, quinolone and macrolide. After administering the antibiotics, they showed a gradually favorable clinical course and recovered without residual complications. A M. pneumoniae infection should be considered as a cause of severe community acquired pneumonia, and empirical treatment targeting this organism might be helpful in treating patients with the severe manifestation.

2 Cases of Mycoplasma pneumoniae Infection with Severe Pneumonia / 결핵및호흡기질환

Mycoplasma pneumoniae (M. pneumoniae) is the leading cause of pneumonia in older children and young adults. Normally, it does not progress to a condition requiring hospitalization but improves spontaneously or has a mild clinical course. We report two cases of M. pneumoniae pneumonia with different clinical manifestations from the normal course. The patients were young healthy individuals. The diagnoses were made by serology. However, it could not be determined beforehand that they had M. pneumoniae pneumonia. Based on the empirical treatment strategy of severe community acquired pneumonia, the patients were treated with broad-spectrum antibiotics including cephalosporin, quinolone and macrolide. After administering the antibiotics, they showed a gradually favorable clinical course and recovered without residual complications. A M. pneumoniae infection should be considered as a cause of severe community acquired pneumonia, and empirical treatment targeting this organism might be helpful in treating patients with the severe manifestation.

Diagnostic Value of Procalcitonin and C-Reactive Protein in Differentiation of Pleural Effusions / 결핵및호흡기질환

BACKGROUND: Malignancies are a common and important causes of exudative pleural effusions. Several tumor markers have been studied because the pleural fluid cytology and pleural biopsy specimens do not provide a diagnosis in a high percentage of malignant effusions. In an attempt to overcome this limitation, procalcitonin and C-reactive protein (CRP) in pleural effusions and serum, which are known to be inflammation markers, were measured to determine if they can differentiate an exudate from trasndate as well as the diverse causes of exudative pleural effusion. METHODS: 178 consecutive patients with pleural effusion (malignant 57, tuberculous 51, parapneumonic 31, empyema 5, miscellaneous benign 7, transudative 27)were studied prospectively. The standard parameters of pleural effusion and measured serum and pleural procalcitonin were examined using in immunoluminometric assay. The level of CRP in serum and pleural fluid was determined by turbidimetric immunoassay. RESULTS: The pleural procalcitonin levels in the exudate were significantly higher than those in the transudate, 0.81+/-3.09 ng/mL and 0.12+/-0.12 ng/mL, respectively (p=0.007). The pleural CRP levels were significantly higher in the exudate than the transudate, 2.83+/-3.31 mg/dL and 0.74+/-0.67 mg/dL, respectively (p<0.001). The pleural procalcitonin levels in the benign effusion were significantly higher than those in the malignant effusion, 1.15+/-3.82 ng/mL and 0.25+/-0.92 ng/mL, respectively (p=0.032). The pleural CRP levels were significantly higher in the benign effusion than in the malignant effusion, 3.68+/-3.78 mg/dL and 1.42+/-1.54 mg/dL, respectively (p<0.001). The pleural procalcitonin levels in the non-tuberculous effusion were significantly higher than those in the tuberculous effusion, 1.16+/-3.75 ng/mL and 0.13+/-0.37 ng/mL, respectively (p=0.008). CONCLUSION: Measuring the level of procalcitonin and CRP in the pleural fluid is helpful for differentiating between transudates and exudates. In addition, it is useful for differentiating between benign and malignant pleural effusions.

The Remission of Pure Red Cell Aplasia with a Thymoma after Surgical Resection / 결핵및호흡기질환

Thymomas are associated with different paraneoplastic syndromes, with the most clinically important association being with myasthenia gravis, hypogammaglobulinemia, and pure red cell aplasia (PRCA). The optimal therapy for PRCA that complicates a thymoma is unknown, given the rarity of the clinical situation. It has been suggested that remission following surgery alone is uncommon and most patients will require some other form of therapy. We report a case of PRCA with a thymoma in a 59-year-old man who remained in complete remission of the PRCA after surgical resection of the thymoma.

Half-turned Truncal Switch Operation for Transposition of Great Arteries, Ventricular Septal Defect and Pulmonic Stenosis / 대한흉부외과학회지

The surgical management of patients with transposition of the great arteries, ventricular septal defect, and pulmonary stenosis remains a challenge. The Rastelli operation or Lecompte operation is the preferred surgical procedure, but its long-term results are not optimal because of a warped left ventricular outflow tract through a space-occupied intraventricular tunnel and a contrived right ventricular outflow tract. We performed a half-turned truncal switch operation as an alternative surgical procedure in a 3-year-old boy (weighing 9.6 kg) with this anomaly. Postoperative echocardiography showed laminar flow through straight and nonobstructive aortic and pulmonary ventricular outflow tracts.

Fistula of Ascending Aorta and Right Atrium Following Percutaneous Transcatheter Atrial Septal Defect Closure / 대한흉부외과학회지

Percutaneous transcatheter closure of atrial septal defects as a therapeutic alternative in appropriate patients provides superior cosmetic results, is less invasive, and allows for shorter hospital stays. Unfortunately, however, such percutaneous procedures can be associated with catastrophic procedure complications that may require immediate surgical intervention. We report a case of aorta-to-right atrial fistula two months after transcatheter occlusion of an atrial septal defect by an Amplatzer septal occluder. Revealed by dyspnea, palpitation and hemolysis, this complication needed an emergency surgical operation. The fistula between the noncoronary Valsalva sinus of the aorta and the right atrium was repaired. The atrial septal defect was closed by patch. The cause of this serious complication appears to be erosion into the aorta by the right atrial disk.

Risk Factor Analysis for Spinal Cord and Brain Damage after Surgery of Descending Thoracic and Thoracoabdominal Aorta / 대한흉부외과학회지

BACKGROUND: Surgery of descending thoracic or thoracoabdominal aorta has the potential risk of causing neurological injury including spinal cord damage. This study was designed to find out the risk factors leading to spinal cord and brain damage after surgery of descending thoracic and thoracoabdominal aorta. MATERIAL AND METHOD: Between October 1995 and July 2005, thirty three patients with descending thoracic or thoracoabdominal aortic disease underwent resection and graft replacement of the involved aortic segments. We reviewed these patients retrospectively. There were 23 descending thoracic aortic diseases and 10 thoracoabdominal aortic diseases. As an etiology, there were 23 aortic dissections and 10 aortic aneurysms. Preoperative and perioperative variables were analyzed univariately and multivariately to identify risk factors of neurological injury. RESULT: Paraplegia occurred in 2 (6.1%) patients and permanent in one. There were 7 brain damages (21%), among them, 4 were permanent damages. As risk factors of spinal cord damage, Crawford type II.III (p=0.011) and intercostal artery anastomosis (p=0.040) were statistically significant. Cardiopulmonary bypass time more than 200 minutes (p=0.023), left atrial vent catheter insertion (p=0.005) were statistically significant as risk factors of brain damage. Left heart partial bypass (LHPB) was statistically significant as a protecting factor of brain (p=0.032). CONCLUSION: The incidence of brain damage was higher than that of spinal cord damage after surgery of descending thoracic and thoracoabdominal aorta. There was no brain damage in LHPB group. LHPB was advantageous in protecting brain from postoperative brain injury. Adjunctive procedures to protect spinal cord is needed and vigilant attention should be paid in patients with Crawford type II.III and patients who have patent intercostal arteries.

The Recovery of Left Ventricular Function after Coronary Artery Bypass Grafting in Patients with Severe Ischemic Left Ventricular Dysfunction: Off-pump Versus On-pump / 대한흉부외과학회지

BACKGROUND: Adverse effects of cardiopulmonary bypass can be avoided by "Off-pump" coronary artery bypass (OPCAB) surgery. Recent studies have reported that OPCAB had the most beneficial impact on patients at highest risk by reducing bypass-related complications. The purpose of this study is to compare the outcome of OPCAB and conventional coronary artery bypass grafting (CCAB) in patients with poor left ventricular (LV) function. MATERIAL AND METHOD: From March 1997 to February 2004, seventy five patients with left ventricular ejection fraction (LVEF) of 35% or less underwent isolated coronary artery bypass grafting at our institute. Of these patients, 33 patients underwent OPCAB and 42 underwent CCAB. Preoperative risk factors, operative and postoperative outcomes, including LV functional change, were compared and analysed. RESULT: Patients undergoing CCAB were more likely to have unstable angina, three vessel disease and acute myocardial infarction among the preoperative factors. OPCAB group had significantly lower mean operation time, less numbers of total distal anastomoses per patient and less numbers of distal anastomoses per patient in the circumflex territory than the CCAB group. There was no difference between the groups in regard to in-hospital mortality (OPCAB 9.1% (n=3) Vs. CCAB 9.5% (n=4)), intubation time, the length of stay in intensive care unit and in hospital postoperatively. Postoperative complication occurred more in CCAB group but did not show statistical difference. On follow-up echocardiography, OPCAB group showed 9.1% improvement in mean LVEF, 4.3 mm decrease in mean left ventricular end-diastolic dimension (LVEDD) and 4.2 mm decrease in mean left ventricular end-systolic dimension (LVESD). CCAB group showed 11.0% improvement in mean LVEF, 5.1 mm decrease in mean LVEDD and 5.5 mm decrease in mean LVESD. But there was no statistically significant difference between the two groups. CONCLUSION: This study showed that LV function improves postoperatively in patients with severe ischemic LV dysfunction, but failed to show any difference in the degree of improvement between OPCAB and CCAB. In terms of operative mortality rate and LV functional recovery, the results of OPCAB were as good as those of CCAB in patients with poor LV function. But, OPCAB procedure was advantageous in shortening of operative time and in decrease of complications. We recommend OPCAB as the first surgical option for patients with severe LV dysfunction.

The Results of Extracardiac Fontan Operation in the Patients with Heterotaxy Syndrome / 대한흉부외과학회지

BACKGROUND: Historically the Fontan operation in patients with single ventricle and heterotaxy syndrome has been associated with high mortality because of systemic or pulmonary anomalous venous drainage, incompetent common atrioventricular valve, right ventricle type univentricular heart, and arrhythmia. MATERIAL AND METHOD: A retrospective review of 62 patients (age: 54.79+/-33.97 months) with heterotaxy syndrome who underwent a extracardiac Fontan operation between 1996 and 2005 was performed. Twenty one patients had left atrial isomerism, and 41 had right isomerism. The Fontan procedure was staged in all but 2 patients, and a fenestration was less placed in left isomerism. RESULT: Left isomerism was associated more with interrupted inferior vena cava and pulmonary arteriovenous fistula, and right isomerism was associated more with anomalous pulmonary venous drainage, common atrioventricular valve and morphologic right ventricle. There were 3 hospital deaths (4.8%), and 3 late deaths (5.2%) with a follow-up duration of 48.8+/-31.0 months. Eight-year survivals were 90.5+/-6.4% in left isomerism and 88.6+/-5.4% in right isomerism (p=0.94). At 8 years, freedom from reoperation was 73.9+/-11.3% in left isomerism, and 82.3+/-6.7% in right isomerism (p=0.87). Atrioventricular valve regurgitation progressed after Fontan operation in heterotaxy syndrome, and reoperation for pulmonary arteriovenous fistula and permanent pacemaker implantation for sinus node dysfunction were required more in left isomerism. CONCLUSION: The extracardiac Fontan operation can now be performed in patients with heterotaxy syndrome with excellent survival. However, morbidity in terms of postoperative atrioventricular valve regurgitation, arrhythmia, and pulmonary arteriovenous fistula remains significant.

Early and Mid-term Results for Repair of Ebstein's Anomaly / 대한흉부외과학회지

BACKGROUND: We evaluated the early and mid-term results for repair of Ebstein's anomaly. MATERIAL AND METHOD: Between January 1989 and June 2004, 29 patients underwent repair of Ebstein's anomaly. The median age was 11.4 years (4 days-50 years). Tricuspid insufficiency equal to or greater than grade 3 was present in 21 (72.4%) patients. Surgical techniques included tricuspid valve repair with vertical plication of the atrialized ventricle (n=14), Carpentier's technique (n=7), tricuspid valve replacement (n=4), systemic-to-pulmonary arterial shunt (n=2), tricuspid valve repair (n=1), and Fontan operation (n=1). Bi-directional cavopulmonary shunt (BCPS) was required in 5 patients. Among the 2 neonates, one patient underwent successful biventricular repair, and the other patient underwent systemic-to-pulmonary arterial shunt. Follow-up was possible in 21 patients (75%), and the average follow-up was 37.6 months (3 months~11.3 years). RESULT: There were 1(3.4%) early and 1 late deaths. Reoperation was required in 4 patients. Two patients underwent tricuspid valve re-replacement, and the other 2 tricuspid valve repair. At recent follow-up, only 2 patients showed tricuspid insufficiency equal to or greater than grade 3, and most patients showed clinical improvement. Excluding the patients who underwent tricuspid valve replacement, the actuarial rate of freedom from reoperation at 1 and 5 years were 94.7% and 79.0%, respectively. CONCLUSION: Tricuspid valve repair was possible in most patients with good mid-term outcome. Most patients showed clinical and hemodynamic improvement. Indications for the BCPS should be clarified.

Right Ventricular Perforation and Left Hemothorax by Permanent Transveneous Pacemaker Lead: Report of 1 Case / 대한흉부외과학회지

Bleeding due to cardiac perforation by endocardial pacemaker lead is a rare complication. We report one case of left hemothorax due to right ventricular perforation after the insertion of permanent transvenous pacemaker. Operative finding showed a pacing lead penetrating right ventricle, pericardium, and left pleura sequentially, but there was no evidence of hemopericardium.

Aortic Valve Papillary Fibroelastoma: Report of 1 Case / 대한흉부외과학회지

Papillary fibroelastomas are benign, and they are the second most common primary cardiac tumors usually involving the cardiac valve. Papillary fibroelastoma attached to the free margin of right coronary cusp of the aortic vlave was found incidentally during the work-up of a 51-year-old woman, who was presented with palpitation and dyspnea. During the operation, the tumor mass was excised without leaving defect on the aortic valve leaflet.

Modified Blalock-Taussig Shunt for the Patients with Complex Congenital Heart Defects in Early Infancy / 대한흉부외과학회지

BACKGROUND: This retrospective review examines the preoperative condition, postoperative course, mortality and cause of death for the patients who underwent modified Blalock-Taussig shunt for complex congenital heart defects in early infancy. MATERIALS AND METHOD: Fifty eight patients underwent modified Blalock-Taussig shunts from January 2000 to November 2003. The mean age at operation was 23.1+/-16.2 days (5~81 days), and the mean body weight was 3.4+/-0.7 kg (2.1~4.3 kg). Indications for surgery were pulmonary atresia with ventricular septal defect in 12 cases, pulmonary atresia with intact ventricular septum in 17, single ventricle (SV) in 18, and hypoplastic left heart syndrome (HLHS) in 11. Total anomalous pulmonary venous return (TAPVR) was associated with SV in 4 cases. RESULT: There were 11 (19.0%) early, and 5 (10.6%) late deaths. Causes of early death included low cardiac output in 9, arrhythmia in 1, and multiorgan failure in 1. Late deaths resulted from pneumonia in 2, hypoxia in 1, and sepsis in 1. Risk factors influencing mortality were preoperative pulmonary hypertension, metabolic acidosis, use of cardiopulmonary bypass, HLHS and TAPVR. Twenty four patients (41.4%) had hemodynamic instability during the 48 postoperative-hours. Six patients underwent shunt revision for occlusion, and 1 shunt division for pulmonary overflow. CONCLUSION: Modified Blalock-Taussig shunt for complex congenital heart defects in early infancy had satisfactory results except in high risk groups. Many patients had early postoperative hemodynamic instability, which means that continuous close observation and management are mandatory in this period. Aggressive management may appear warranted based on understanding of hemodynamic changes for high risk groups.