Intrapleural streptokinase in a two-year-old child with a parapneumonic effusion

A two-year-old child was hospitalised with features of parapneumonic effusion. He was initially managed with parenteral antibiotics and chest tube drainage. After three days drainage became insignificant inspite of chest tube being patent and appropriately positioned. CT scan of chest showed multiloculated effusion. In view of multiloculated effusion it was decided to try intrapleural fibrinolysis with streptokinase. Streptokinase in a dose of 1,25000 IU dissolved in 50 ml of normal saline was instilled through the chest tube daily. After instilling three doses, there was a significant increase in the drainage followed by almost complete radiological resolution. There were no side effects. Intrapleural streptokinase is a useful adjunctive threapeutic modality in the management of complicated parapneumonic effusion or empyema in paediatric patients.     

Echo-guided management of complicated parapneumonic effusion in children

The optimal management of parapneumonic effusion and empyema in children remains controversial; currently there is insufficient evidence to give clear guidance on therapy. The aims of this study were to delineate the biochemical characteristics and to examine the effect of different therapeutic strategies on ultrasound staging of parapneumonic effusion. The ultrasonic appearances were classified according to the deposition of fibrin or formation of fibrin septations. A total of 81 patients were enrolled in the present study. Chest ultrasound was performed and results were stratified into anechoic fluid (stage 1, n = 23), with floating fibrin strands (stage 2, n = 30), and with septated fibrin (stage 3, n = 28). The mean days of fever elapsed before detection of these stages appeared to be higher at advanced stages (7.3 +/- 2.1 vs. 8.5 +/- 2.7 vs. 9.7 +/- 4.2, respectively; P = 0.03). Univariate analysis revealed that WBC, platelet count in hemogram and pH, glucose, protein, LDH in pleural effusion were significantly associated with the stages of parapneumonic effusion. Multivariate logistic analysis revealed that pH (less than 7.27) in pleural fluid was the only significant factor for the formation of fibrin with/without fibrin septations. The rate of successful tube drainage decreased as the advancement of stages of parapneumonic effusion, especially in patients using chest tube for drainage initially (P = 0.001). Total duration of fever and hospital stay was significantly shorter for those children who had initial video-assisted thoracic surgery (VATS) compared to those who had initial chest tube drainage (P < 0.001). Chest sonography can well discriminate the progressive stages of bacterial parapneumonic effusion. In children with a progressive parapneumonic effusion with fibrin formation, early aggressive tube drainage may avoid a subsequent surgical intervention. In children with a fibrin septated parapneumonic effusion, an initial VATS is recommended to shorten the duration of fever and hospital stay.     

Immediate drainage is not required for all patients with complicated parapneumonic effusions

We retrospectively investigated if the clinical course of complicated parapneumonic effusions was altered by treatment with immediate drainage plus antibiotics vs antibiotics alone. The two groups of patients had no significant differences in age, duration of symptoms prior to hospitalization, initial maximum temperature, WBC count, or characteristics of the pleural fluid. There were no differences in the duration of hospitalization, fever, elevated WBC count, intravenous antibiotic therapy, or the time for roentgenographic resolution of the effusions. There was one death in each group. The infection of the pleural space resolved in 13 of 16 patients treated with antibiotics alone. No recurrence of the infection of the pleural space occurred in these patients. Antibiotics alone were not sufficient in two cases which eventually required chest tube drainage. Therefore, not all complicated parapneumonic effusions require drainage. A prospective study is required to determine if chest tube drainage should be part of the initial management of complicated parapneumonic effusions.     

Intrapleurally administered streptokinase in the treatment of acute loculated nonpurulent parapneumonic effusions.

Adequate pleural drainage is believed to be an essential component of the management of low pH-low glucose parapneumonic effusion. Parapneumonic effusions may become loculated rapidly, preventing adequate drainage with a single chest tube. Administration of intrapleural streptokinase may be effective in promoting drainage for loculated, nonpurulent low pH-low glucose parapneumonic effusions when fibrin adhesions may not yet be organized. Intrapleural streptokinase was used in 12 patients with relatively large, symptomatic, loculated, nonpurulent parapneumonic effusions in whom the initial thoracentesis demonstrated a pH less than or equal to 7.0 and/or glucose less than or equal to 40 mg/dl, and when inadequate drainage was demonstrated roentgenographically despite tube thoracostomy. Mean pleural fluid WBC was 9,750/mm3 (range, 1 to 27 K), and pleural fluid glucose and pH were 33 +/- 21 mg/dl and 6.95 +/- 0.19, respectively. A solution of streptokinase, 250,000 units in normal saline, was given intrapleurally via the chest tube. Effectiveness of intrapleural streptokinase was assessed radiographically and by monitoring the volume of fluid drained from the chest tube after streptokinase instillation. A greater than 50% improvement in the CXR was seen in nine of 12 patients after intrapleural administration of streptokinase. The volume of fluid out in the first 48 h post-streptokinase was 849 +/- 836 ml (range, 100 to 3,000). In addition, clinical improvement (decreased chest discomfort, less dyspnea, or reduced fever) was noted in eight of 12 patients after streptokinase treatment. We conclude that intrapleural administration of streptokinase is an effective adjunct to the management of nonpurulent, loculated parapneumonic effusions that may reduce the need for multiple chest tubes or surgical drainage.     

Parapneumonic effusions and empyema

Nearly 50 per cent of patients with acute bacterial pneumonia have an accompanying pleural effusion (parapneumonic effusion). With appropriate antibiotic therapy, the pleural effusion will resolve along with the pneumonia in the majority of patients. However, in a small fraction, the pleural effusion will not resolve unless drainage of the pleural space is instituted. Such patients are said to have complicated parapneumonic effusions. It is important to identify patients with complicated parapneumonic effusions as early as possible, since tube drainage of the pleural space becomes increasingly difficult the longer its institution is delayed. The possibility of a complicated parapneumonic effusion should be considered in every patient with bacterial pneumonia. If both diaphragms cannot be distinctly identified throughout their length on the lateral chest radiograph, decubitus chest radiographs should be obtained. If the thickness of the fluid on the decubitus radiograph is greater than 10 mm, a diagnostic thoracentesis should be performed. Only pleural fluid analysis can identify patients with complicated parapneumonic effusions. Complicated parapneumonic effusions are characterized by low pleural fluid pH and glucose levels, a high pleural fluid LDH, and a positive Gram stain of the pleural fluid. Tube thoracostomy should be performed immediately in a patient with an acute bacterial pneumonia if the pleural fluid glucose is below 40 mg per 100 ml, the pleural fluid pH is below 7.00, or if the Gram stain of the pleural fluid is positive. Patients with pleural fluid pH above 7.20, pleural fluid LDH below 1000 IU per L, and pleural fluid glucose levels above 40 mg per 100 ml respond well to only the administration of appropriate antibiotics.(ABSTRACT TRUNCATED AT 250 WORDS)     

Predicting factors for outcome of tube thoracostomy in complicated parapneumonic effusion for empyema

STUDY OBJECTIVES: To determine the predicting factors for outcome of tube thoracostomy in patients with complicated parapneumonic effusion (CPE) or empyema. DESIGN AND SETTINGS: Retrospective chart review over a 55-month period at a tertiary referred medical center. PATIENTS AND MEASUREMENTS: The medical charts of patients with empyema or CPE were reviewed. Data including age, gender, clinical symptoms, important underlying diseases, leukocyte count, duration of preadmission symptoms, interval from first procedure to second procedure, the time from first procedure to discharge (recovery time), the amount of effusion drained, administration of intrapleural streptokinase, chest tube size and position, loculation of pleural effusion, and characteristics and culture results of pleural effusion were recorded and compared between groups of patients with successful and failed outcome of tube thoracostomy drainage. RESULTS: One hundred twenty-one patients were selected for study. One hundred of these patients had received tube thoracostomy drainage with 53 successful outcomes and 47 failed outcomes of chest tube drainage. Nineteen patients received decortication directly, and the other two received antibiotics alone. Univariate analysis showed that pleural effusion leukocyte count, effusion amount, and loculation of pleural effusion were significantly related to the outcome of chest tube drainage. Multiple logistic regression analysis demonstrated that loculation and pleural effusion leukocyte count < or = 6,400/uL were the only independent predicting factors related to failure of tube thoracostomy drainage. CONCLUSIONS: Loculation and pleural effusion leukocyte count < or = 6,400/microL were independent predicting factors of poor outcome of tube thoracostomy drainage. These results suggest that if the initial attempt at chest tube drainage fails, early surgical intervention should be considered in good surgical candidates with loculated empyema or pleural effusion with leukocyte count < or = 6,400/microL.     

Parapneumonic effusion and pleural empyema - topical aspects of classification, diagnosis and treatment

Parapneumonic effusions can be diagnosed in about 40 - 50 % of patients with bacterial pneumonia, and therefore should be considered as a frequent condition. Despite their prevalence, there is limited consensus about diagnostic pathways and therapeutic procedures due to the lack of evidence-based data available. The classification of parapneumonic effusions is based on morphological, chemical and bacteriological criteria. Dependent on the complexity of the effusion, available management approaches include observation without intervention, thoracentesis, chest tube drainage with or without local fibrinolysis and the surgical options VATS and thoracotomy. This overview summarizes the actual aspects of classification, diagnosis and treatment of the parapneumonic effusion and draws conclusions for the daily management of this condition.     

Treatment of complicated parapneumonic pleural effusion with intrapleural streptokinase in children

OBJECTIVE: To evaluate the role of intrapleural streptokinase in the management of complicated parapneumonic effusions in children. DESIGN: Prospective comparative study. SETTING: Cheng Kung University Hospital, a tertiary medical center in Tainan, Taiwan. PATIENTS AND METHODS: We enrolled as our prospective study group 20 consecutive children with complicated parapneumonic effusions who received intrapleural streptokinase treatment between August 2000 and July 2002. We also retrospectively analyzed a comparison group of 22 consecutive children with complicated parapneumonic effusions who received chest tube drainage without streptokinase treatment from January 1992 to July 2000. We then compared the clinical manifestations and outcome of these two patient groups. The patient population (21 boys and 21 girls) ranged in age from 9 to 130 months (mean age, 41.5 +/- 26.3 months [mean +/- SD]). The characters of pleural effusion showed no difference between the two groups. Nineteen patients had positive findings for Streptococcus pneumoniae, 2 patients had positive findings for Staphylococcus aureus, 2 patients had positive findings for Pseudomonas aeruginosa, and 19 patients had undetermined pathogens. All patients were treated with appropriate antibiotics. RESULTS: More pleural fluid was drained from the streptokinase group than from the comparison group during streptokinase treatment (816 +/- 481 mL vs 279 +/- 238 mL, p < 0.01). The duration of fever after chest tube insertion was also significantly lower in the study group (5.3 +/- 3.1 days vs 7.9 +/- 4.6 days, p < 0.05). Only two patients in the streptokinase group required surgical intervention compared with nine patients in the comparison group (p < 0.05). No major side effects were noticed after streptokinase instillation. CONCLUSION: Intrapleural fibrinolytic treatment with streptokinase is safe and effective, and it can obviate the need for surgery in most cases. The combination treatment should be attempted early on, when complicated parapneumonic effusion is first diagnosed.     

Intrapleural streptokinase in multiloculated malignant pleural effusion

Intrapleural administration of fibrinolytic agents has been shown to be effective and safe in the treatment of loculated parapneumonic effusions. Its use in multiloculated malignant pleural effusions has been rarely reported. We report a case of malignant multiloculated pleural effusion who failed to respond to standard chest tube drainage but showed dramatic and complete resolution with intrapleural streptokinase.     

Pleural fluid pH in parapneumonic effusions.

The pH and carbon dioxide tension were measured in 24 consecutive parapneumonic effusions, along with the leukocyte count, leukocytic differential count, and levels of glucose and protein. Three categories of parapneumonic effusions were characterized: (1) empyemas; (2) benign (nonloculated) effusions; and (3) loculated effusions. A pH greater than 7.30 was present in all ten benign effusions, and spontaneous resolution occurred in each case. All ten empyemas and the four loculated effusions had a pH less than 7.30. All four loculated effusions required drainage with a chest tube for resolution. The pH of the pleural fluid alone separated the empyemas and loculated effusions from benign effusions. The early separation of parapneumonic effusions on the basis of the pleural fluid appears useful. If the pH is greater than 7.30, a benign effusion is present, and spontaneous resolution is likely. If the pH is less than 7.30, loculation of the pleural space may occur regardless of whether the effusion fulfills the criteria for empyema.     

Medical management of parapneumonic pleural disease

Considerable heterogeneity exists in the management of parapneumonic pleural disease. A randomized controlled trial (RCT) demonstrated the effectiveness of small-catheter drainage with fibrinolysis, but surgical devotees suggest this may only be applicable to "early" cases. We examined evidence-based medical management in "all-comers." We performed a retrospective database analysis of the management of all children with complex pleural effusion admitted to the John Radcliffe Hospital over the 7-year period 1996-2003. One hundred and ten children were admitted. Ten were excluded as they were part of a multicenter RCT and had received intrapleural saline instead of urokinase. Of the remaining 100, 51 were female and 49 male. Median age on admission was 5.8 years (range, 0.3-16.5). Symptoms preadmission averaged 11 days, with December the most common month for presentation. Ninety-six underwent chest ultrasound, confirming an effusion in all, described as loculated/septated (68) or echogenic (11). In 17 cases, no specific comment was made regarding the nature of the fluid seen on ultrasound. Ninety-five had subsequent chest tube drainage and then received intrapleural fibrinolysis with urokinase. An etiological organism was identified in 21 cases (21%) (Streptococcus pneumoniae in 10, group A Streptococcus in 5, Staphylococcus aureus in 4, Haemophilus influenzae in 1, and coliform in 1). In a further 9 cases (9%), Gram-positive organisms were seen on pleural fluid microscopy, but did not grow on culture. Two (2%) required surgery due to the persistence of symptoms and an inadequate response to medical management. Median duration of admission was 7 days (range, 2-21 days); median duration of stay from intervention was 5 days (range, 2-19 days). At median follow-up of 8 weeks (range, 3-20 weeks), all children were symptom-free, with minimal pleural thickening on chest X-ray. In conclusion, antibiotic therapy with chest drain insertion and intrapleural urokinase is effective in treating complex parapneumonic effusion and is associated with a good long-term outcome.     

Thoracoscopic decortication as first-line therapy for pediatric parapneumonic empyema. A case series

STUDY OBJECTIVES: Previous articles have promoted the early use of thoracotomy and decortication for refractory empyema. This study examines thoracoscopy and decortication at the time of initial chest tube placement in pediatric patients with parapneumonic empyema. DESIGN: We reviewed the medical records of 16 consecutive patients who were children with parapneumonic empyema. RESULTS: Thirteen children (group 1) underwent thoracoscopic decortication and tube thoracostomy as their initial operative procedures; 3 children (group 2) had tube thoracostomy alone. In both groups, chest tubes were removed prior to their discharge to home. The mean (+/- SD) operative time for thoracoscopy was 81 +/- 19 min with no complications. On average, chest tubes were removed by postoperative day 4. The mean time to discharge was 8.3 days. Two children eventually required lobectomy. The mean operative time for chest tube placement alone was 21 +/- 3 min. Children required chest tube drainage for an average of 12.3 days. The mean time to discharge was 16.6 days. Two patients required a total of five additional operative procedures, including two additional chest tube placements, two open decortications, and one lobectomy. CONCLUSIONS: Thoracoscopic decortication is effective in the early treatment of pediatric parapneumonic empyema. It facilitates visualization, evacuation, and mechanical decortication of the pleural space with no additional morbidity and may lead to reduced time for chest tube drainage, shorter hospitalization, and more rapid clinical recovery.     

Acute pneumonia and empyema caused by Mycobacterium intracellulare

Nontuberculous mycobacterial infection is rarely accompanied by pleural involvement. We report a very rare case of M. intracellulare pulmonary disease with pleural empyema. A 56-year-old man was admitted to our hospital because of fever, purulent sputum and pleuritic chest pain. A chest radiograph and CT revealed pneumonic consolidation in the left lower lobe and loculated hydropneumothorax. The sputum smear was positive for acid fast bacilli. The aspirated pleural fluid was grossly purulent and the smear of the pleural effusion was also positive for acid fast bacilli. M. intracellulare was identified by culture and PCR from sputum and pleural fluid specimens. The patient improved with percutaneous tube drainage of the purulent effusion and antibiotic treatment including clarithromycin, rifampicin, ethambutol and streptomycin.     

Parapneumonic pleural effusion and empyema

At least 40% of all patients with pneumonia will have an associated pleural effusion, although a minority will require an intervention for a complicated parapneumonic effusion or empyema. All patients require medical management with antibiotics. Empyema and large or loculated effusions need to be formally drained, as well as parapneumonic effusions with a pH <7.20, glucose <3.4 mmol/l (60 mg/dl) or positive microbial stain and/or culture. Drainage is most frequently achieved with tube thoracostomy. The use of fibrinolytics remains controversial, although evidence suggests a role for the early use in complicated, loculated parapneumonic effusions and empyema, particularly in poor surgical candidates and in centres with inadequate surgical facilities. Early thoracoscopy is an alternative to thrombolytics, although its role is even less well defined than fibrinolytics. Local expertise and availability are likely to dictate the initial choice between tube thoracostomy (with or without fibrinolytics) and thoracoscopy. Open surgical intervention is sometimes required to control pleural sepsis or to restore chest mechanics. This review gives an overview of parapneumonic effusion and empyema, focusing on recent developments and controversies.     

Video-assisted thoracoscopic surgery in the treatment of complicated parapneumonic effusions or empyemas: outcome of 234 patients

STUDY OBJECTIVE: To review our experience in treatment of complicated parapneumonic effusion and pleural empyema by video-assisted thoracoscopic surgery (VATS). DESIGN: Retrospective chart review. SETTING: Taiwanese medical centers. PATIENTS: A total of 234 patients (108 women, 126 men; median age, 51 years; range, 0.75 to 84 years) underwent procedures for parapneumonic effusion (145 patients) or pleural empyema (89 patients) between May 1995 and December 2003. All patients had chest radiographs, and 188 patients (80.3%) underwent preoperative CT or sonography. More than 85% (200 patients) received preoperative diagnostic or therapeutic thoracentesis, tube thoracostomy, or fibrinolytics. Indications for VATS included empyema refractory to medical control or peel or multiloculated exudates per CT and chest tapping. INTERVENTIONS: Septal lysis and debridement irrigation through one port (31 patients, 13.2%), decortication and debridement through two or three ports (179 patients, 76.5%), or rib resection or larger utility incision for decortication and drainage (24 patients, 10.3%). RESULTS: Mean +/- SD procedural time was 64.3 +/- 22.5 min (range, 26 to 244 min). Sixteen patients (6.8%) needed further surgery for empyema (9 patients required open drainage or thoracoplasty, and 7 patients needed redecortication or repair of bronchopleural fistula). There were no intraoperative deaths and only eight (3.4%) perioperative deaths (< 30 days), which were mostly unrelated to surgery. Of the 234 patients, 202 patients (86.3%) achieved satisfactory results with VATS treatment. Patients requiring open decortication or repeat procedures (40 patients) had a longer mean duration of preoperative symptoms, longer mean duration of preoperative hospitalization, and a higher ratio of pleural empyema (vs complicated parapneumonic effusion) than patients undergoing simple VATS. CONCLUSIONS: VATS is safe and effective for treatment of complicated parapneumonic effusion and pleural empyema. Earlier intervention with VATS can produce better clinical results. A prospective study should be done to identify optimal timing and settings for VATS treatment for both complicated parapneumonic effusion and pleural empyema.     

New trends in the diagnosis and treatment in parapneumonic effusion and empyema

Despite treatment with antibiotics, patients with complicated parapneumonic effusion (PPE) and empyema have an increased morbidity and mortality due at least in part to inappropriate management of the pleural effusion. PPE should be considered in all patients with pneumonia as antibiotic therapy is being initiated. If the diaphragms cannot be seen throughout their length on the chest radiographs, a lateral decubitus radiograph, ultrasonography or computerized tomography scan should be obtained. If the effusion is more than 10 mm in thickness, a therapeutic thoracentesis should be performed. If the fluid cannot all be removed and the characteristics of the pleural fluid indicate a poor prognosis, a chest tube should be inserted. If the drainage is incomplete due to loculation of the PPE intrapleural fibrinolytics or thoracoscopy should be performed. If the lung does not reexpand completely with thoracoscopy, then decortication should be performed without delay.     

Clinical relevance and characteristics of pleural effusion in patients with Mycoplasma pneumoniae pneumonia

Abstract Data regarding parapneumonic pleural effusion in Mycoplasma pneumoniae pneumonia (MP) patients are limited. In this study MP patients with pleural effusion tended to be younger and had longer hospital stays and more common use of systemic steroids compared to those without pleural effusion. In 5 of the 6 patients for whom pleural fluid data were available, the pleural effusion was lymphocyte-predominant rather than polymorphonuclear leukocyte-predominant; these patients also had elevated adenosine deaminase levels. Taken together, these results indicate that MP patients with pleural effusion may have a more severe form compared to those without pleural effusion. M. pneumoniae should be considered an aetiological agent of lymphocyte-predominant pleural effusion.     

肺炎旁胸腔积液现状与治疗进展

胸膜腔感染在世界范围内都有很高的发病率和病死率,而且近些年其发病率是逐年上升的.并不是所有的胸膜腔感染都合并肺部疾病,许多患者并不能在胸腔积液中发现病原微生物.一部分患者由于未能及时诊治而演变成复杂性胸腔积液,甚至脓胸,影响了治疗的结局.肺炎旁胸腔积液的治疗要根据细菌的特征、胸腔积液生化分析,做到早期诊断、及时的抗生素治疗和必要的胸水引流.胸腔积液特征,特别是pH值,是评估胸腔积液性质非常有用的指标.纤溶剂能够促进胸水引流和疾病恢复.如果内科保守治疗失败,可选择外科手术治疗,如电视辅助胸腔镜、开胸胸膜剥脱术等.     

Usefulness of the British Thoracic Society and the American College of Chest Physicians guidelines in predicting pleural drainage of non-purulent parapneumonic effusions

AIM: To assess the value of the British Thoracic Society (BTS) and the American College of Chest Physicians (ACCP) guidelines to predict which patients with non-purulent parapneumonic effusions (PPE) warrant chest tube drainage. METHODS: A retrospective chart review was performed on all patients who underwent thoracentesis because of a PPE over a 10-year period at a Spanish medical center. Classification of PPE as complicated (CPPE) or uncomplicated (UPPE) was based on the clinician's decision to insert a chest tube to resolve the effusion. Empyema was defined as pus in the pleural space. Data collected included patient demographics, size of the effusion, and microbiological and pleural fluid chemistries that might influence the physician's decision to place a chest tube. RESULTS: Of the 240 patients with PPE who entered the study, 85 had UPPE, 67 had CPPE, and 88 had empyema. Individual pleural fluid parameters, namely a pH<7.20, a glucose<40 mg/dL or <60 mg/dL, a LDH>1000 U/L or a positive culture had a relatively high specificity (from 78% for LDH to 94% for glucose<40 mg/dL), but low to moderate sensitivity (from 25% for culture to 73% for LDH) in predicting the need for chest tube placement in non-purulent PPE. While pleural fluid cultures performed poorly in discriminating UPPE from CPPE (likelihood ratio positive 1.7), effusion's size performed the best (likelihood ratio positive 5.7). BTS and ACCP guidelines yielded measures of sensitivity (98% and 97%, respectively), and negative likelihood ratio (0.03 and 0.05, respectively) for identifying a CPPE. CONCLUSIONS: Both guidelines have similar accuracy and perform satisfactorily in distinguishing CPPE from UPPE, albeit at an admissible cost of needlessly increasing chest tube drainage.     

Diagnostically significant variations in pleural fluid pH in loculated parapneumonic effusions

STUDY OBJECTIVES: Parapneumonic effusions are common, and measurement of pleural pH is one of the most useful measurements in assessing the need for tube drainage. Use of pleural pH assumes that a single measurement conveys a representative picture of pH throughout the effusion. Often effusions are multiloculated, and varying concentrations of nondiffusible acids such as lactic acid, if present in different concentrations, could mean clinically significant variations in pH between locules. If these differences were large, a single pH measurement could misrepresent the "stage" that the parapneumonic effusion had reached. We therefore set out to test the hypothesis that pH varies significantly between locules in complicated parapneumonic effusions. DESIGN: The study was performed in seven consecutive patients presenting to our institution with complicated parapneumonic effusions. INTERVENTIONS: In each case, pleural pH was measured in several separate pleural fluid locules, using ultrasound-guided pleural fluid sampling. RESULTS: Significant variations were found in pleural fluid visual appearance, pH, and lactate dehydrogenase between locules in four of seven patients. Three of seven patients had variations, resulting in pH levels both above and below 7.2, which is the threshold used in our institution to indicate the need for tube drainage. CONCLUSIONS: This is the first reported series of variation in pleural pH between different locules in complicated parapneumonic effusions. These variations are clinically important and cast light on the mechanisms responsible for the acidosis seen in infected effusions. Physicians should be aware of this when making drainage decisions in these patients using the clinical picture and a single pH result alone.