Scoring system for empyema thoracis and help in management
http://www.100md.com
《美国医学杂志》
Department of Pediatrics, Chang Gung Children's Hospital, Taiwan
Abstract
Objective : To evaluate the implications of a newly defined severity scoring of empyema in children for the prediction of surgical management and to compare the length of hospitalization as an outcome measure of patients treated using medical therapy, salvage video-assisted thoracoscopic surgery (VATS) vs early elective VATS. Methods : A retrospective chart review of parapneumonic empyema of patients below 18 years of age admitted to a tertiary children's hospital in northern Taiwan from April 1993 to December 2002 was performed. Patients were categorized into a medical group who received antibiotic therapy, needle aspirations with/without tube thoracostomy; a salvage VATS group when the patients required surgery for the relief of persistent fever > 38oC, chest pains or dyspneic respirations despite initial medical therapy; an early VATS group when the patients received elective surgery early after admission. The demographic data, clinical features, laboratory findings, and duration of hospitalization were compared using a severity score of empyema (SSE). Results : Streptococcus pneumoniae was the most common infecting organism, followed by Staphylococcus aureus , Pseudomonas aeruginosa . No organisms were recovered in 39% of patients. A pleural pH < 7.1 increases the odds of requiring surgical intervention by 6 times among this cohort. Children who required decortication of empyema had a higher severity score (mean 4.8 vs 3.0, p < 0.005). The duration of hospitalization for patients having early VATS showed a shortening stay (mean 18 vs 28 days) as compared to salvage VATS. Conclusion : A pleural pH < 7.1 and a newly designed clinical severity score of empyema 3 4 are two predictors of surgical intervention for fibrinopurulent empyema in the present study. Early elective VATS may be adopted not later than 7 days after failure of appropriate antibiotic therapy and adequate drainage of empyema to decrease the length of stay and minimize morbidity.
Keywords: Empyema; Severity scoring; Video-assisted thoracoscopic surgery
The optimal management of empyema remains controversial. [1],[2],[3] Some investigators advocate antibiotics in combination with tube thoracostomy and/or intrapleural thrombolytics, [4],[5],[6],[7] while others advocate the use of early surgical intervention such as video thoracoscopy and pleural debridement. [8],[9],[10] Although prognostic factors of mortality for severe community-acquired pneumonia and pleural fluid analysis have been validated to direct therapy for parapneumonic empyema in adults, [11],[12],[13]there is no published data on the utility of clinical severity scoring to predict the prognosis of empyema in children.[8] The aims of the study were to (1) compare the clinical characteristics and laboratory findings of the patients who were successfully and conservatively and those who required surgical intervention; (2) determine whether a newly defined severity scoring of empyema can predict the necessity of surgical intervention for fibrinopurulent empyema in children; (3) to compare the length of hospitalization between medically treated patients, patients who required salvage video-assisted thoracoscopic surgery (VATS) and early VATS.
Materials and Methods
Charts of patients aged less than 18 years identified by a computer search for the discharge diagnosis of empyema thoracis in Chang Gung Children's Hospital (CGCH) between April 1993 and December 2002 were reviewed. CGCH is a university-affiliated hospital which serves both as a primary and tertiary referral center in northern Taiwan. Patients were excluded from the analysis if they had received parenteral antibiotics for > 5 days or had a thoracostomy tube insertion prior to admission into CGCH. Patients with underlying diseases (congenital heart disease, cerebral palsy, postoperative empyema) or known immunodeficiencies were also excluded.
Demographic data were collected including the presenting symptoms and laboratory findings of the patients; comparisons were made between patients who had medical therapy (antibiotics with/without chest tube drainage), salvage VATS group of patients who had persistent fever, chest pain or dyspnea despite conservative treatment for > 7 days,[14] and early VATS group for those patients who had VATS ￡ 7 days of conservative treatment. The microbiology profile obtained isolated from blood or pleural aspirates was identified and the susceptibility to antimicrobials was determined. Severity scoring of empyema (SSE) was assessed in each case 3-5 days after admission and scored according to the criteria: 1 point was assigned to each of the following entries regarding clinical features, laboratory findings and radiographic features table1. The maximal SSE in each case was 20.
The complications and morbidity of patients during hospitalization were recorded and analyzed. The length of stay was defined as the duration of hospitalization after admission into CGCH.
Statistics
Statistical analysis was performed using the SPSS software, version 10. The student's t test was used for comparing differences of continuous values; percentages were compared using the chi-square test or Fisher Exact test. When more than two groups were compared, the Kruskal-Wallis test was used for non-parametric data but one-way analysis of variance (ANOVA) was used for comparison of means for continuous values between 3 groups. A 2-tailed p value < 0.05 was considered significant.
Results
Patient Demographics, Clinical Characteristics, Laboratory Findings
A total of 81 patients were included in the study. The average age of the patients was 37.9 ±26.0 months (mean ±SD) with a range of 6 weeks to 15 years. The male to female ratio was 1.25:1 (45 boys and 36 girls). The most common presenting symptoms were fever, cough, dyspnea and decreased activity table2. Laboratory analysis showed that a significant higher percentage of patients had pleural pH < 7.1 for those who had undergone surgery table3. Microbiological examination revealed a diverse group of organisms as shown in table4. For Streptococcus pneumoniae isolated, 23.3% were susceptible to penicillin (MIC ￡0.06 mg/mL), 43.3% were intermediate resistant (MIC 0.12 - 1.0 mg/mL) and 13.3 % were highly resistant to penicillin (MIC 32 mg/mL).
Severity Scoring of Empyema and Clinical Course
Patients with an SSE of 3 4 have 4.6 times chance of requiring surgery intervention than those with SSE of <4 in parapneumonic empyema in the present study table3. The patients in the medical group also stayed for significantly shorter period of time as compared to the patients who had VATS. In order to study the outcome of therapy and the time of surgical intervention, the patients who had undergone surgery were further sub-categorized into a salvage VATS or an early VATS group. SSE for salvage VATS vs early VATS was not different, but the duration of hospitalization was significantly shorter (mean 18.0 vs 27.9 days) for the patients who had early VATS than the salvage group. The patients having conservative treatment had a mean SSE of 3.0 which was significantly lower than the surgical group of patients having a score of 4.8 table5.
Discussion
In this retrospective review of children with empyema it has been found that children with an SSE of 4 or above had a 4.6 times chance of requiring surgical intervention than medical therapy. The optimal therapy of parapneumonic empyema remains controversial with a multiplicity of available options. Some authors advocate conservative treatment of empyema using solely appropriate antibiotic therapy and/or closed tube drainage because children seem to have a greater capacity to resorb thickened pleura effectively as compared to adults.[4] With the advance of thoracic computed scanning, increasing number of necrotizing pneumonitis in complicated pneumonia has been recognized,[14] however, it must be emphasized that the decision to perform decortication on patients should be persistent sepsis, rather than reliance on the roentgenographic appearance.[15],[16]
Recently, the use of fibrinolytic agents or decortication in patients with loculations and septation during sonographic examinations has been shown to reduce morbidity and shorten hospital stay. [8], [17],[18],[19],[20] However, Chan and colleagues in a 26-year retrospective review of fibrinopurulent empyema from Montreal Children's Hospital demonstrated that complete drainage was achieved in 7 (18%) of 39 patients, and although 25 (64%) patients had persistent loculations after tube drainage, only 7 patients required decortication.[5] Till date there is only one randomized trial comparing the use of intrapleural urokinase versus saline in children, but the selection of the patients may not be qualified as truly fibrinopurulent empyema in these 60 children,[6],[21] Therefore, solid evidence supporting the routine use of intrapleural fibrinolytic therapy in the treatment of parapneumonic empyema in children is still lacking.[7], [22],[23],[24]
In the present study, the authors used clinical features, laboratory findings and radiographic features on thoracic computed tomographic scans for the prediction of success empyema when medically treated. The average duration of fever was 10.6 days in the medical group vs 12.4 days in patients who had surgery; these patients had an average stay of 23.7 and 27.4 days respectively. The longer stay in patients who had undergone surgery signified the initial selection of patients who failed to response to conservative therapy exclusively.
In the past decades, video-assisted thoracoscopic surgery had been advocated more frequently for decreasing morbidity and shortening length of stay in complicated parapneumonic empyema in adults and children.[2],[3], [8],[9],[10],[23] The present data suggest that pleural pH < 7.1 and SSE 3 4 are two predictors for the necessity of surgical intervention in fibrinopurulent stage of empyema table3. The course of conservative management was usually prolonged with a mean stay of 23.7±8.1 days using antibiotic therapy and pleural drainage only. For patients with refractory fever, dyspneic respirations and chest pain despite adequate medical therapy and early elective VATS revealed a shorter length of hospitalization as compared to salvage VATS table4. If children with SSE 3 4 are subjected to early VATS, it may be possible to curtail the length of stay in hospital for patients and apply a sequential oral home medication, more aggressive to comply a more modern trend of therapy to achieve shorter hospitalization stay. Finally, multicenter randomized prospective studies are urgently needed to determine the optimal therapy of parapneumonic empyema in children.
References
1. Galladay E, Wagner C. Management of empyema in children. Am J Surg 1989; 158 : 618-621.
2. Khakoo GA, Goldstraw P, Hansell DM, Bush A. Surgical treatment of parapneumonic empyema. Pediatr Pulmonol 1996; 22 : 348-356.
3. Shankar KR, Kenny SE, Okoye BO, Carty HML, Losty PD. Evolving experience in the management of empyema thoracis. Acta Paediatr 2000; 89: 417-420.
4. Gocmen A, Kiper N, Toppare M, Ozcelik U, Cengizlier R, Cetinkaya F. Conservative treatment of empyema in children. Respiration 1993; 60 : 182-185.
5. Chan W, Keyser-Gauvin E, Davis GM, Nguyen LT, Laberge JM. Empyema thoracis in children: a 26-year review of the Montreal Children's Hospital experience. J Pediatr Surg 1997; 32 : 870-872.
6. Thomson AH, Hull J, Kumar MR, Wallis C, Balfour Lynn IM. Randomized trial of intrapleural urokinase in the treatment of childhood empyema. Thorax 2002; 57 : 343-347.
7. Balci AE, Eren S, ülkü R, Eren MN. Management of multiloculated empyema thoracis in children: thoracotomy versus fibrinolytic treatment. Eur J Cardio Thorac Surg 2002; 22 : 595-598.
8. Hoff S, Neblett W, Edwards KM, Heller RM, Pietsch JB, Holcomb GW, Hocomb III GW. Parapneumonic empyema in children: decortication hastens recovery in patients with severe pleural infections. Pediatr Infect Dis J 1991; 10 : 194-199.
9. Grewal H, Jackson RJ, Wagner CW, Smith SD. Early video-assisted thoracic surgery in the management of empyema. Pediatrics 1999; 103 : e63.
10. Subramaniam R, Joseph VT, Tan GM, Goh A, Chay OM. Experience with video-assisted thoracoscopic surgery in the management of complicated pneumonia in children. J Pediatr Surg 2001; 36 : 316-319.
11. British Thoracic Society Research Committee: Community acquired pneumonia in adults in British hospitals in 1982-1983; A survey of aetiology, mortality, prognostic factors and outcome. QJ Med 1987; 62 : 195-200.
12. Torres A, Serra-Batlles J, Ferrer A, Jimenez P, Celis R, Cobo E, Rodriguez-Roisin R. Severe community-acquired pneumonia. Am Rev Respir Dis 1991; 144 : 312-318.
13. Ewig S, Bauer T, Hasper E et al. Prognostic analysis and predictive rule for outcome of hospital-treated community acquired pneumonia. Eur Resp J 1995; 8 : 392-397.
14. Liu HP, Hsieh MJ, Lu HI, Liu YH, Wu YC, Lin PJ. Thoracoscopic-assisted management of postpneumonic empyema in children refractory to medical response. Surg Endosc 2002; 16 : 1612-1614.
15. Wong KS, Chiu CH, Yeow KM, Huang YC, Liu HP, Lin CY. Necrotizing pneumonitis in children. Eur J Pediatr 2000; 159: 684-688.
16. Kennedy AS, Agness M, Bailey L, White JJ. Decortication for childhood empyema. Arch Surg 1991; 126 : 1287-1291.
17. Chen KY, Liaw YS, Wang HC, Luk KT, Yang PC. Sonographic septation: a useful prognostic indicator of acute thoracic empyema. J Ultrasound Med 2000; 19 : 837-843.
18. Ramnath RR, Heller RM, Ben-Ami T, Miller MA, Campbell P, Neblett III WW, Holcomb GW, Hernanz-Schulman H. Implications of early sonographic evaluation of parapneumonic effusions in children with pneumonia. Pediatrics 1998; 101 : 68-71.
19. Shankar S, Gulati M, Kang M, Gupta S, Suri S. Image-guided percutaneous drainage of thoracic empyema: can sonography predict the outcome Eur Radiol 2000; 10 : 495-499.
20. Rosen H, Nadkarni V, Theroux, Padman R, Klein J. Intrapleural streptokinase as adjunctive treatment for persistent empyema in pediatric patients. Chest 1993; 103 : 1190-1193.
21. Cohen G, Hjortdal V, Ricci M, Jaffe A, Wallis C, Dinwiddie R, Elliott MJ, de Leval MR. Primary thoracoscopic treatment of empyema in children. J Thorac Cardiovasc Surg 2003; 125 : 79-84.
22. Barbato A, Panizzolo C, Monciotti C, Marcucci F, Stefanutti G, Gamba PG. Use of urokinase in childhood pleural empyema. Pediatr Pulmonol 2003; 35 : 50-55.
23. Krishman S, Amin N, Dozor AJ, Stringel G. Urokinase in the management of complicated parapneumonic effusions in children. Chest 1997; 112 : 1579-1583.
24. Kercher KW, Attorri RJ, Hoover JD, Morton D. Thoracoscopic decortication as first-line therapy for pediatric parapneumonic empyema - a case series. Chest 2000; 118 : 24-27(Wong KS, Lin TY, Huang YC)
Abstract
Objective : To evaluate the implications of a newly defined severity scoring of empyema in children for the prediction of surgical management and to compare the length of hospitalization as an outcome measure of patients treated using medical therapy, salvage video-assisted thoracoscopic surgery (VATS) vs early elective VATS. Methods : A retrospective chart review of parapneumonic empyema of patients below 18 years of age admitted to a tertiary children's hospital in northern Taiwan from April 1993 to December 2002 was performed. Patients were categorized into a medical group who received antibiotic therapy, needle aspirations with/without tube thoracostomy; a salvage VATS group when the patients required surgery for the relief of persistent fever > 38oC, chest pains or dyspneic respirations despite initial medical therapy; an early VATS group when the patients received elective surgery early after admission. The demographic data, clinical features, laboratory findings, and duration of hospitalization were compared using a severity score of empyema (SSE). Results : Streptococcus pneumoniae was the most common infecting organism, followed by Staphylococcus aureus , Pseudomonas aeruginosa . No organisms were recovered in 39% of patients. A pleural pH < 7.1 increases the odds of requiring surgical intervention by 6 times among this cohort. Children who required decortication of empyema had a higher severity score (mean 4.8 vs 3.0, p < 0.005). The duration of hospitalization for patients having early VATS showed a shortening stay (mean 18 vs 28 days) as compared to salvage VATS. Conclusion : A pleural pH < 7.1 and a newly designed clinical severity score of empyema 3 4 are two predictors of surgical intervention for fibrinopurulent empyema in the present study. Early elective VATS may be adopted not later than 7 days after failure of appropriate antibiotic therapy and adequate drainage of empyema to decrease the length of stay and minimize morbidity.
Keywords: Empyema; Severity scoring; Video-assisted thoracoscopic surgery
The optimal management of empyema remains controversial. [1],[2],[3] Some investigators advocate antibiotics in combination with tube thoracostomy and/or intrapleural thrombolytics, [4],[5],[6],[7] while others advocate the use of early surgical intervention such as video thoracoscopy and pleural debridement. [8],[9],[10] Although prognostic factors of mortality for severe community-acquired pneumonia and pleural fluid analysis have been validated to direct therapy for parapneumonic empyema in adults, [11],[12],[13]there is no published data on the utility of clinical severity scoring to predict the prognosis of empyema in children.[8] The aims of the study were to (1) compare the clinical characteristics and laboratory findings of the patients who were successfully and conservatively and those who required surgical intervention; (2) determine whether a newly defined severity scoring of empyema can predict the necessity of surgical intervention for fibrinopurulent empyema in children; (3) to compare the length of hospitalization between medically treated patients, patients who required salvage video-assisted thoracoscopic surgery (VATS) and early VATS.
Materials and Methods
Charts of patients aged less than 18 years identified by a computer search for the discharge diagnosis of empyema thoracis in Chang Gung Children's Hospital (CGCH) between April 1993 and December 2002 were reviewed. CGCH is a university-affiliated hospital which serves both as a primary and tertiary referral center in northern Taiwan. Patients were excluded from the analysis if they had received parenteral antibiotics for > 5 days or had a thoracostomy tube insertion prior to admission into CGCH. Patients with underlying diseases (congenital heart disease, cerebral palsy, postoperative empyema) or known immunodeficiencies were also excluded.
Demographic data were collected including the presenting symptoms and laboratory findings of the patients; comparisons were made between patients who had medical therapy (antibiotics with/without chest tube drainage), salvage VATS group of patients who had persistent fever, chest pain or dyspnea despite conservative treatment for > 7 days,[14] and early VATS group for those patients who had VATS ￡ 7 days of conservative treatment. The microbiology profile obtained isolated from blood or pleural aspirates was identified and the susceptibility to antimicrobials was determined. Severity scoring of empyema (SSE) was assessed in each case 3-5 days after admission and scored according to the criteria: 1 point was assigned to each of the following entries regarding clinical features, laboratory findings and radiographic features table1. The maximal SSE in each case was 20.
The complications and morbidity of patients during hospitalization were recorded and analyzed. The length of stay was defined as the duration of hospitalization after admission into CGCH.
Statistics
Statistical analysis was performed using the SPSS software, version 10. The student's t test was used for comparing differences of continuous values; percentages were compared using the chi-square test or Fisher Exact test. When more than two groups were compared, the Kruskal-Wallis test was used for non-parametric data but one-way analysis of variance (ANOVA) was used for comparison of means for continuous values between 3 groups. A 2-tailed p value < 0.05 was considered significant.
Results
Patient Demographics, Clinical Characteristics, Laboratory Findings
A total of 81 patients were included in the study. The average age of the patients was 37.9 ±26.0 months (mean ±SD) with a range of 6 weeks to 15 years. The male to female ratio was 1.25:1 (45 boys and 36 girls). The most common presenting symptoms were fever, cough, dyspnea and decreased activity table2. Laboratory analysis showed that a significant higher percentage of patients had pleural pH < 7.1 for those who had undergone surgery table3. Microbiological examination revealed a diverse group of organisms as shown in table4. For Streptococcus pneumoniae isolated, 23.3% were susceptible to penicillin (MIC ￡0.06 mg/mL), 43.3% were intermediate resistant (MIC 0.12 - 1.0 mg/mL) and 13.3 % were highly resistant to penicillin (MIC 32 mg/mL).
Severity Scoring of Empyema and Clinical Course
Patients with an SSE of 3 4 have 4.6 times chance of requiring surgery intervention than those with SSE of <4 in parapneumonic empyema in the present study table3. The patients in the medical group also stayed for significantly shorter period of time as compared to the patients who had VATS. In order to study the outcome of therapy and the time of surgical intervention, the patients who had undergone surgery were further sub-categorized into a salvage VATS or an early VATS group. SSE for salvage VATS vs early VATS was not different, but the duration of hospitalization was significantly shorter (mean 18.0 vs 27.9 days) for the patients who had early VATS than the salvage group. The patients having conservative treatment had a mean SSE of 3.0 which was significantly lower than the surgical group of patients having a score of 4.8 table5.
Discussion
In this retrospective review of children with empyema it has been found that children with an SSE of 4 or above had a 4.6 times chance of requiring surgical intervention than medical therapy. The optimal therapy of parapneumonic empyema remains controversial with a multiplicity of available options. Some authors advocate conservative treatment of empyema using solely appropriate antibiotic therapy and/or closed tube drainage because children seem to have a greater capacity to resorb thickened pleura effectively as compared to adults.[4] With the advance of thoracic computed scanning, increasing number of necrotizing pneumonitis in complicated pneumonia has been recognized,[14] however, it must be emphasized that the decision to perform decortication on patients should be persistent sepsis, rather than reliance on the roentgenographic appearance.[15],[16]
Recently, the use of fibrinolytic agents or decortication in patients with loculations and septation during sonographic examinations has been shown to reduce morbidity and shorten hospital stay. [8], [17],[18],[19],[20] However, Chan and colleagues in a 26-year retrospective review of fibrinopurulent empyema from Montreal Children's Hospital demonstrated that complete drainage was achieved in 7 (18%) of 39 patients, and although 25 (64%) patients had persistent loculations after tube drainage, only 7 patients required decortication.[5] Till date there is only one randomized trial comparing the use of intrapleural urokinase versus saline in children, but the selection of the patients may not be qualified as truly fibrinopurulent empyema in these 60 children,[6],[21] Therefore, solid evidence supporting the routine use of intrapleural fibrinolytic therapy in the treatment of parapneumonic empyema in children is still lacking.[7], [22],[23],[24]
In the present study, the authors used clinical features, laboratory findings and radiographic features on thoracic computed tomographic scans for the prediction of success empyema when medically treated. The average duration of fever was 10.6 days in the medical group vs 12.4 days in patients who had surgery; these patients had an average stay of 23.7 and 27.4 days respectively. The longer stay in patients who had undergone surgery signified the initial selection of patients who failed to response to conservative therapy exclusively.
In the past decades, video-assisted thoracoscopic surgery had been advocated more frequently for decreasing morbidity and shortening length of stay in complicated parapneumonic empyema in adults and children.[2],[3], [8],[9],[10],[23] The present data suggest that pleural pH < 7.1 and SSE 3 4 are two predictors for the necessity of surgical intervention in fibrinopurulent stage of empyema table3. The course of conservative management was usually prolonged with a mean stay of 23.7±8.1 days using antibiotic therapy and pleural drainage only. For patients with refractory fever, dyspneic respirations and chest pain despite adequate medical therapy and early elective VATS revealed a shorter length of hospitalization as compared to salvage VATS table4. If children with SSE 3 4 are subjected to early VATS, it may be possible to curtail the length of stay in hospital for patients and apply a sequential oral home medication, more aggressive to comply a more modern trend of therapy to achieve shorter hospitalization stay. Finally, multicenter randomized prospective studies are urgently needed to determine the optimal therapy of parapneumonic empyema in children.
References
1. Galladay E, Wagner C. Management of empyema in children. Am J Surg 1989; 158 : 618-621.
2. Khakoo GA, Goldstraw P, Hansell DM, Bush A. Surgical treatment of parapneumonic empyema. Pediatr Pulmonol 1996; 22 : 348-356.
3. Shankar KR, Kenny SE, Okoye BO, Carty HML, Losty PD. Evolving experience in the management of empyema thoracis. Acta Paediatr 2000; 89: 417-420.
4. Gocmen A, Kiper N, Toppare M, Ozcelik U, Cengizlier R, Cetinkaya F. Conservative treatment of empyema in children. Respiration 1993; 60 : 182-185.
5. Chan W, Keyser-Gauvin E, Davis GM, Nguyen LT, Laberge JM. Empyema thoracis in children: a 26-year review of the Montreal Children's Hospital experience. J Pediatr Surg 1997; 32 : 870-872.
6. Thomson AH, Hull J, Kumar MR, Wallis C, Balfour Lynn IM. Randomized trial of intrapleural urokinase in the treatment of childhood empyema. Thorax 2002; 57 : 343-347.
7. Balci AE, Eren S, ülkü R, Eren MN. Management of multiloculated empyema thoracis in children: thoracotomy versus fibrinolytic treatment. Eur J Cardio Thorac Surg 2002; 22 : 595-598.
8. Hoff S, Neblett W, Edwards KM, Heller RM, Pietsch JB, Holcomb GW, Hocomb III GW. Parapneumonic empyema in children: decortication hastens recovery in patients with severe pleural infections. Pediatr Infect Dis J 1991; 10 : 194-199.
9. Grewal H, Jackson RJ, Wagner CW, Smith SD. Early video-assisted thoracic surgery in the management of empyema. Pediatrics 1999; 103 : e63.
10. Subramaniam R, Joseph VT, Tan GM, Goh A, Chay OM. Experience with video-assisted thoracoscopic surgery in the management of complicated pneumonia in children. J Pediatr Surg 2001; 36 : 316-319.
11. British Thoracic Society Research Committee: Community acquired pneumonia in adults in British hospitals in 1982-1983; A survey of aetiology, mortality, prognostic factors and outcome. QJ Med 1987; 62 : 195-200.
12. Torres A, Serra-Batlles J, Ferrer A, Jimenez P, Celis R, Cobo E, Rodriguez-Roisin R. Severe community-acquired pneumonia. Am Rev Respir Dis 1991; 144 : 312-318.
13. Ewig S, Bauer T, Hasper E et al. Prognostic analysis and predictive rule for outcome of hospital-treated community acquired pneumonia. Eur Resp J 1995; 8 : 392-397.
14. Liu HP, Hsieh MJ, Lu HI, Liu YH, Wu YC, Lin PJ. Thoracoscopic-assisted management of postpneumonic empyema in children refractory to medical response. Surg Endosc 2002; 16 : 1612-1614.
15. Wong KS, Chiu CH, Yeow KM, Huang YC, Liu HP, Lin CY. Necrotizing pneumonitis in children. Eur J Pediatr 2000; 159: 684-688.
16. Kennedy AS, Agness M, Bailey L, White JJ. Decortication for childhood empyema. Arch Surg 1991; 126 : 1287-1291.
17. Chen KY, Liaw YS, Wang HC, Luk KT, Yang PC. Sonographic septation: a useful prognostic indicator of acute thoracic empyema. J Ultrasound Med 2000; 19 : 837-843.
18. Ramnath RR, Heller RM, Ben-Ami T, Miller MA, Campbell P, Neblett III WW, Holcomb GW, Hernanz-Schulman H. Implications of early sonographic evaluation of parapneumonic effusions in children with pneumonia. Pediatrics 1998; 101 : 68-71.
19. Shankar S, Gulati M, Kang M, Gupta S, Suri S. Image-guided percutaneous drainage of thoracic empyema: can sonography predict the outcome Eur Radiol 2000; 10 : 495-499.
20. Rosen H, Nadkarni V, Theroux, Padman R, Klein J. Intrapleural streptokinase as adjunctive treatment for persistent empyema in pediatric patients. Chest 1993; 103 : 1190-1193.
21. Cohen G, Hjortdal V, Ricci M, Jaffe A, Wallis C, Dinwiddie R, Elliott MJ, de Leval MR. Primary thoracoscopic treatment of empyema in children. J Thorac Cardiovasc Surg 2003; 125 : 79-84.
22. Barbato A, Panizzolo C, Monciotti C, Marcucci F, Stefanutti G, Gamba PG. Use of urokinase in childhood pleural empyema. Pediatr Pulmonol 2003; 35 : 50-55.
23. Krishman S, Amin N, Dozor AJ, Stringel G. Urokinase in the management of complicated parapneumonic effusions in children. Chest 1997; 112 : 1579-1583.
24. Kercher KW, Attorri RJ, Hoover JD, Morton D. Thoracoscopic decortication as first-line therapy for pediatric parapneumonic empyema - a case series. Chest 2000; 118 : 24-27(Wong KS, Lin TY, Huang YC)