Respiratory functional outcomes improvement with intervention in chronic empyema thoracis: a retrospective analysis

Abstract

Introduction

Chronic pleural empyema is usually a consequence of in adequate treatment of acute pleural empyema. The incidence of tubercular and post-intervention empyema has increased in underdeveloped or developing countries adding to economic burden on the society. We have performed a retrospective analysis on role of intervention in chronic empyema to improve respiratory functional outcomes.

Methods

We retrospectively reviewed data of 115 patients of chronic tubercular and parapneumonic empyema thoracis to evaluate change in functional outcome parameters based on their treatment modalities during follow-up in department of surgery, King George’s Medical University, Lucknow, India. Accordingly, four groups were made—group 1 (tube thoracostomy), group 2 (decortication by video-assisted thoracoscopic surgery (VATS)), group 3 (decortication by open thoracotomy), and group 4 (window thoracostomy followed by thoracomyoplasty).

Results

Significant improvement was noted in forced expiratory volume in one second (FEV1)% and forced vital capacity (FVC)% in all groups. In spirometry, percent change in mean FEV1 from pre-intervention to post-intervention was increase of 55.4%, 38.3%, 47.2, and 59.21% in group 1, group 2, group 3, and group 4 respectively, and percent change in mean FVC from pre-intervention to post-intervention was increase of 53.30%, 38.11%, 51.23, and 54.21% in group 1, group 2, group 3, and group 4 respectively.

Conclusion

Our study showed that a significant increase was observed in FVC and FEV1 from pre to post among all the groups. Comparable improvement of functional outcomes with non-operative intervention in properly selected patients can be achieved.

Introduction

An empyema persisting for more than 4 weeks is classified as chronic empyema [1]. It is usually a consequence of inadequate treatment of acute pleural empyema and leads to significant morbidity and prolonged hospitalization. The incidence of tubercular and post-intervention empyema has increased in underdeveloped or developing countries leading to increase in disability adjusted life years (DALY), severely impacting quality of life and adding to economic burden on the society [2]. Various treatment are applied to treat chronic empyema that include medical management (antibiotics and antitubercular) in combination with interventions like intercostal tube drainage, along with chest physiotherapy, decortication by open thoracotomy as well as by VATS, window thoracostomy, and thoracomyoplasty depending on duration of disease and condition of lung parenchyma. It has been said that early surgical treatment in these patients allows the lung to re-expand and prevent subsequent chronic respiratory impairment with improved functional outcomes [3]. Although the role of surgery in chronic infectious pleural disease is well demonstrated, only a few studies have studied the role of intervention (surgical or non-surgical) in pleural empyema in improving functional outcomes. Therefore, we undertook a retrospective non randomized study to evaluate the impact of various intervention methods on functional outcome parameters of respiratory function in patients of chronic empyema thoracis.

Materials and methods

We retrospectively reviewed data (patient case record sheet and OPD follow-up visit) of 115 patients of chronic tubercular and parapneumonic empyema thoracis and their treatment modality during follow-up in department of surgery King George’s Medical University, Lucknow, U.P., India from March 2014 to February 2017. Patients with other lung disease like lung abscess, bronchogenic carcinoma, traumatic chest injuries, and ruptured liver abscess, and patients with other chronic comorbid conditions were excluded from our study.

Group division based on treatment modality

Data was collected regarding treatment modality adopted in individual patients, taking into consideration their clinical and radiological characteristics. We made four groups—group 1 comprising patients managed by tube thoracostomy, groups 2 and 3 included patients managed by decortication by VATS and open thoracotomy, and group 4 comprised management done by window thoracostomy followed by thoracomyoplasty. In group 1, patients were managed by USG guided intercostal drainage (ICD) tube placement with or without prior USG-guided pus aspiration, chest physiotherapy, incentive spirometry, nutritional supplementation, and regular follow-up. In groups 2 and 3, we did decortication by VATS and by thoracotomy respectively in patients who were not responding to conservative management. In group 4, window thoracostomy was performed in patients having severe parenchymal destruction, and it was followed by thoracomyoplasty. Antibiotic and antitubercular treatments were given in each group according to standard institutional protocol and revised national tuberculosis control program (RNTCP) guidelines [4].

Procedure and outcome variables

Data was recorded both before and after intervention for demographic characteristics (age, sex,), etiology of chronic empyema (tubercular or non-tubercular), clinical features, and pulmonary functional evaluation by spirometry. Primary outcome variables included pulmonary functional outcome measures (FVC measured as percentage of predicted values, FEV1 measured as percentage of predicted values, and FEV1/FVC ratio), and they were compared in each treatment group before (at the time of admission) and after management (6 weeks after discharge).

Statistical analysis

Continuous data were summarized as mean ± standard error of the mean (SE), while discrete (categorical) in number and percentage (%). Continuous groups were compared by independent Student’s t test. Categorical groups were compared by chi-square (χ2) test. A two-tailed p value less than 0.05 (p < 0.05) was considered statistically significant. Analyses were performed on the SPSS software (Windows version 17.0, IBM).

Results

Demographic profile of patients

In our study, 115 patients were included in which 95(80%) were males. Based on therapeutic intervention, all patients were divided into four groups as described in methodology with group 1 (tube thoracostomy), group 2 (decortication by VATS), group 3 (decortication by open thoracotomy), and group 4 (window thoracostomy followed by thoracomyoplasty) having 23, 7, 13, and 72 patients each respectively. The age was insignificantly (p > 0.05) different in the groups (Table 1). There was no mortality in patients of our study.

Table 1.

Comparison of patient characteristics and various outcome measures in different study groups

	Group 1 Tube thoracostmy N = 23	Group 2 VATS N = 7	Group 3 Open decortication N = 72	Group 4 Window thoracostmy followed by thoracomy plasty N = 13	P value
Demography, n (%)
Male	18 (78.3)	6 (90)	56 (77.8)	12 (92.3)	0.77
Female	5 (21.7)	1 (10)	16 (22.2)	1 (7.7)
Etiology, n (%)
Tubercular	15 (62.3)	5 (71.4)	54 (75.0)	13 (100)	0.70
Non-tubercular	8 (37.7)	2 (28.6)	18 (25.0)	0 (0)
Side, n (%)
Bilateral	2 (8.6)	0 (0)	0 (0)	0 (0)	0.77
Right	16 (69.5)	3 (42.9)	44 (61.1)	9 (69.2)
Left	5 (21.7)	4 (57.1)	28 (38.9)	4 (31.8)
Clinical features (pre-operative symptoms), n (%)
Fever	22 (95.7)	6 (85.7)	68 (94.4)	12 (92.3)	0.23
Cough with expectoration	22 (95.7)	4 (57.1)	67 (93.1)	10 (76.9)	0.01
Chest pain	14 (60.9)	4 (57.1)	50 (69.4)	12 (92.3)	0.32
Hemoptysis	1 (4.3)	1 (14.3)	1 (1.4)	2 (15.3)	0.06
Breathlessness	14 (60.9)	5 (71.4)	48 (66.7)	10 (76.9)	0.35
Clinical features (post-operative symptoms), n (%)
Pain	7 (30.4)	4 (57.1)	36 (50)	9 (69.2)	0.24
Fever	12 (52.2)	0 (0)	26 (36.1)	6 (36.1)	< 0.001
Bleeding	0 (0)	0 (0)	1 (1.4)	1 (7.6)	< 0.001
Length of hospital stay
Hospital stay (days, mean ± SD)	9.37 ± 1.94	14.57 ± 2.76	18.36 ± 5.99	21.14 ± 6.54	< 0.001
Spirometry, mean ± s.d
FEV1% (Pre  Post)	40.78 ± 12.24 63.09 ± 12.07	51.71 ± 13.85 71.43 ± 18.02	40.64 ± 12.02 59.62 ± 12.69	26.46 ± 10.94 42.23 ± 13.81	< 0.001 < 0.001
	< 0.001	< 0.001	< 0.001	< 0.001
FVC% (Pre  Post)	37.87 ± 12.15 58.26 ± 10.69	48.14 ± 13.88 66.71 ± 14.94	37.32 ± 10.96 56.25 ± 13.14	24.46 ± 9.26 37.77 ± 11.15	< 0.001 < 0.001
	< 0.001	< 0.001	< 0.001	< 0.001
FEV1/FVC (Pre  Post)	1.080 ± 0.096 1.075 ± 0.119	1.08 ± 0.68 1.07 ± 0.116	1.09 ± 1.06 1.075 ± 0.103	1.082 ± 0.11 1.12 ± 0.054	0.92 < 0.001
	0.96	0.81	0.33	0.21

Etiology and side of pathology

Bilateral disease was present in only 8.6% of the patients of group 1. However, right-sided pathology was found in majority of patients as compared to left side (Table 1). Majority of the patients were post-tubercular etiology (in all the groups but the difference was statistically not significant (p > 0.05) (Table 1).

Clinical symptoms

Most common symptom was fever with presence in 108 (91.52%) patients across all groups, and groups 1 and 3 had 22 (95.7%) and 68 (94.4%) patients with fever respectively. Cough and expectoration was present in 22 (95.7%), 4 (57.10%), 67 (93.10%), and 10 (76.9%) in groups 1, 2, 3, and 4 patients. Chest pain was present in 14 (60.90%), 4 (57.10%), 50 (69.4%), and 12 (92.3%) in groups 1, 2, 3, and 4. Hemoptysis was presenting complaint in 1 (4.3%), 1 (14.3%), 1 (1.4%), and 2 (15.3%) in groups 1, 2, 3, and 4 patients. Breathlessness was present in 14 (60.90%), 5 (71.40%), 48 (66.7%), and 10 (76.9%) in groups 1, 2, 3, and 4 patients respectively.

Spirometric analysis

In spirometry, changes in mean FEV1 from pre-intervention to post-intervention were 40.78 ± 12.24 to 63.09 ± 12.07 (55.4% increase), 51.71 ± 13.85 to 71.43 ± 18.02 (38.3% increase), 40.64 ± 12.02 to 59.62 ± 12.69 (47.2% increase), 26.46 ± 10.94 to 42.23 ± 13.81 (59.21% increase) in groups 1, 2, 3, and 4 respectively (Table 1, Fig. 1). Changes in mean FVC from pre-intervention to post-intervention were 37.87 ± 12.15 to 58.26 ± 10.69 (53.30% increase), 48.14 ± 13.88 to 66.71 ± 14.94% (38.11% increase), 37.32 ± 10.96 to 56.25 ± 13.14 (51.23% increase), and 24.46 ± 9.26/37.77 ± 11.15% (54.21% increase) in groups 1, 2, 3, and 4 respectively (Table 1). Changes in mean FEV1/FVC from pre-intervention to post-intervention was 1.080 ± 0.096 to 1.075 ± 0.119, 1.08 ± 0.68 to 1.07 ± 0.116, 1.09 ± 1.06 to 1.075 ± 0.103, and 1.082 ± 0.11 to 1.12 ± 0.054 in groups 1, 2, 3, and 4 respectively (Table 1, Fig. 1). Significant increase was observed in FVC and FEV1 from pre- to post-intervention among all the groups. There was no significant (p > 0.05) change in the ratio of FEV1/FVC among all the groups (Table 1, Fig. 2).

Fig. 1.

Proportional change in FEV1% and FVC % from pre-intervention to post-intervention

Fig. 2.

Change in ratio—FEV1/FVC from pre-intervention to post-intervention

Symptoms (post-operative)

Pain was the most common complaint in follow-up period with incidence of 30.4%, 57.1%, 50%, and 59.2% in groups 1, 2, 3, and 4 respectively. Fever was present in 52.2%, 0%, 36.1%, and 36.1% in groups 1, 2, 3 and 4 respectively.

Discussion

Chronic empyema remains a major cause of morbidity and despite increasing variations in modalities; the goals of therapy still remain the same, i.e., to get rid of morbidity and to prevent mortality. Determination of techniques necessary to achieve these goals must be tailored according to the individual patient. The management in chronic empyema involves non-operative intervention (Intercostal tube drainage), either alone or in combination with operative intervention (VATS, open decortication, and window thoracostomy/thoracomyoplasty). We have evaluated various interventions done in chronic empyema with regard to changes in functional outcomes in patients of chronic empyema thoracis by spirometric analysis.

In our study, significant improvement in functional outcome parameters—FEV1 and FVC—was seen in all groups, but FEV1/FVC ratio was not changed significantly in any group. Changes in FEV1, FVC, and FEV/FVC ratio were maximum in group 4 with patients managed by window thoracostomy followed by thoracomyoplasty. Intervention in empyema thoracis is necessary, but should be tailored according to the patient’s needs. Previous studies [5] done on empyema have revealed the positive role of surgical intervention, both VATS and open technique, in improving functional respiratory outcomes. VATS was associated with reduced operative time, an early removal of chest drains and a shorter post-operative hospital stay and better radiological results than open thoracotomy. But, we could not find any single study in literature encompassing the role of whole spectrum of intervention done in chronic empyema to improve functional respiratory outcomes; thus, our study is probably the first to do so. With regard to etiology and clinical features of chronic empyema, majority of our cases had tuberculosis (78.26%) with fever (93.9%), cough and expectoration (89.6%), and chest pain (69.6%) as most common symptoms. Most studies [6–11] from India have found that empyemas caused by tuberculosis range from 29 to 85.1% of all cases. This predominance of tubercular empyema was in stark contrast to another study on 117 patients [12], which revealed 95 non-tuberculous and 41 tuberculous empyema patients. The major limitation of our study is that it is a retrospective study. Moreover, we have not included data on duration of clinical symptoms, stage-wise (exudative/fibrinopurulent/organized) classification of patients, radiological investigations, and duration of antitubercular therapy before or after intervention, although national guidelines [4] were followed in treatment of pulmonary tuberculosis, which included periodic consultation and follow-up with pulmonologist. With regard to follow-up, another limitation is non-inclusion of data on quality of life scores during the intervention period. All of these limitations can be dealt with in a well-designed, prospective, randomized clinical trial.

Conclusion

Our study showed that a significant increase was observed in FVC and FEV1 from pre- to post-intervention among all the groups. Decortication was indicated in most of the patients of chronic empyema, who were fit, by either open technique or VATS. It may be suggested that comparable improvement in respiratory functional outcomes can be achieved in properly selected patients, managed by both non-operative/operative intervention.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical approval

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

Informed consent

Informed consent was obtained from all individual participants included in the study.