Video-Assisted Thoracoscopic Surgery for Pediatric Empyema by Two-Port Technique: A Single-Center Experience with 167 Consecutive Cases.

BACKGROUND/
PURPOSE: The aim of our study is to determine efficacy, safety, and feasibility of video-assisted thoracoscopic surgery (VATS) in childhood empyema with a technique of only two ports and open instruments at a tertiary care center in India.
METHODS: This is a retrospective study of patients below 18 years, with empyema presenting to the Department of Pediatric Surgery of a Tertiary Care Referral Hospital in India, over a period of 9 years who underwent VATS decortication. Only two ports with open surgical instruments were used. The patients were assessed on the basis of mean duration of preoperative symptoms, duration of surgery, average blood loss, postoperative pain relief, complications, and need for redo surgery.
RESULTS: A total of 97 patients underwent primary VATS decortications without inserting an intercostal drainage (ICD) tube and 70 patients as a secondary procedure after ICD tube was inserted. Mean duration of symptoms was 11 days. The average blood loss during surgery was estimated to be 170 cc. The mean duration of surgery was 90 min. The most common postoperative complication was air leak seen in 19.16% of patients. Minor leaks usually settled by 24 h. In eight patients, a negative suction had to be applied to the ICD tube for persistent air leak. The average length of postoperative stay was 4 days. Two patients required a repeat open decortication procedure due to nonresolution of symptoms and poor lung expansion after VATS. Patients had minimal pain and excellent cosmetic outcome after VATS.
CONCLUSION: Two-port VATS decortication procedure is as feasible and effective as three-port procedure for decortication with better cosmetic result and pain relief.

INTRODUCTION

Empyema is the suppuration within the pleural cavity, most commonly a complication of acute bacterial pneumonia.[1] It is one of the most common diseases in children in India.[2] Prognosis is excellent, provided appropriate treatment is administered early in the course of the disease. Different therapeutic options are available for the management of childhood empyema. Available expertise and resources determine the choice of a particular treatment modality at the appropriate stage of the disease. We share our experience of 167 consecutive cases using two-port technique using video-assisted thoracoscopic surgery (VATS) in children with empyema using direct open instruments. VATS can be done as a primary procedure (without intercostal drainage [ICD] tube insertion) or as a secondary procedure (for inadequate lung expansion after ICD insertion). The technical considerations and results of the same are discussed in the study.

Methods

Preoperative workup

This is a retrospective study of patients with empyema thoracis, presenting to the department between August 2005 and August 2014 and who underwent VATS decortication. One hundred and sixty-seven children between the ages of 1 month and 15 years were included in the study. The majority of children underwent VATS as a primary procedure. The diagnosis was suspected on a history and clinical examination and confirmed by X-ray chest and ultrasound-guided pleural aspiration in all patients. Pleural tap confirmed pus in the pleural cavity and was evaluated by bacteriological and biochemical analysis.[13] Following criteria of the fluid was diagnostic: pH <7.20, lactate dehydrogenase <1000 IU/L, glucose <40 mg/dL, white blood cells >100/dL, and presence of bacteria. Preoperatively, children with hemoglobin values <9 mg/dL received a blood transfusion. Serum protein analysis was done which reflected the nutritional status of the patient and the appropriate nutritional supplement was given. A blood gas analysis was done to evaluate the patients’ cardiopulmonary status. Computed tomography scan of the chest was done when indicated. Appropriate antibiotics were started, and emphasis was given to chest physiotherapy. Aggressive incentive spirometry was encouraged to all the children.

The management of empyema depended on the duration of symptoms, and the presence and absence of respiratory distress. Early diagnosed cases of empyema with a history of 1-week duration and localized collection on ultrasound were subjected to ultrasonography-guided aspiration and fibrinolytics if available. If the collection was generalized, then an intercostal tube was placed and the child reevaluated clinically and with X-ray after 3 days. If they do not reveal adequate resolution, then VATS decortication was performed. If the duration of symptoms was between 1 and 2 weeks without respiratory distress, then primary VATS decortication was performed; if the duration of symptoms is between 1 and 2 weeks with respiratory distress, then an ICD was inserted and the child reevaluated. The children with duration of history more than 2 weeks were subjected to open decortication, as the peel gets organized and thick, thus making it difficult to remove using VATS. A summary of our treatment protocol is shown in Figure 1.

Figure 1

Summary of treatment protocol

Inclusion criteria

Patients of empyema thoracis with age <18 years and presenting before 2 weeks from the onset of symptoms who required VATS decortication were included in the study.

Exclusion criteria

Patients with very thick pleural peel (>1 cm) or long-standing empyema (>2 weeks duration) were offered open decortication as it was not feasible to achieve effective clearance thoracoscopically and were excluded from the study.

Surgical technique

All patients were operated under general anesthesia by one of the three pediatric surgeons in the department. Patients were operated in lateral decubitus position with bolster under the chest and arm raised above the shoulder. CO2 insufflation was used only in few cases for initial visualization if necessary. Two monitors were used on either side of the patient with the surgeon standing on side opposite to the side of collection. Two ports of 5 mm were used interchangeably. In primary VATS (without a previous intercostal drain), the first port is placed in the midaxillary line as high up as possible, usually in 3rd or 4th intercostal space. The second port is inserted at the site of the future intercostal drain, which will be kept postoperatively in all children. In secondary VATS, i.e., in cases in which an intercostal drain had previously been inserted, the site of the drain was used as the first port site and the second port site was tailored according to the site of the maximum peel or collection present. One port was used as a camera port with a trocar, and from the other port, a direct open instrument usually a long artery forceps was used. The instruments were interchanged to achieve maximum clearance. First, the parietal peel was tackled followed by the visceral peel. Adequacy of decortication was confirmed by the visualization of expanding lung. Intraoperative blood loss was replaced with blood or blood products as necessary. Thorough toileting of chest cavity was done. Postoperatively, an appropriately sized ICD tube, with the underwater seal was kept. The pleural cavity was usually drained with an intercostal drain between 5 and 7 days till the drain output decreased, and the column in the intercostal drain bag stopped moving. Postoperatively, all patients were continued with antibiotics and good analgesia. Aggressive chest physiotherapy and incentive spirometry were continued in the postoperative period in all patients. In patients with persistent air leak, a low negative suction (10–20 cm of H2O) to underwater seal was applied.

The parameters studied included age, sex, duration of symptoms, clinical findings, bacteriological, and biochemical study of liquid. The outcome measures included technical difficulties, postoperative complications, blood loss, duration of drainage, and length of hospitalization. The period of follow-up ranged from 6 months to 3 years.

RESULTS

The cohort of 167 patients included 106 boys and 61 girls aged between 1 month and 15 years. The mean age of patients was 4.7 years. About 43.71% of the children who were operated were <3 years of age. A total of 97 patients underwent primary VATS decortication compared to 70 patients with the secondary procedure. Mean duration of symptoms was 11 days. The mean blood loss during surgery was estimated to be 170 cc. The mean duration of surgery was 90 min (range 45–200 min). Two patients required conversion to open thoracotomy due to ineffective clearance of pleural peel by VATS.

The most common postoperative complication was air leak seen in 19.16% of patients. Minor leaks usually settled within 24–48 h. Eight patients had prolonged air leak, which required application negative suction for prolonged duration. Patients had ICD for 5–7 days. There were two conversions to open surgery due to inadequate clearance of peel by VATS. Significant subcutaneous emphysema was observed in six patients. Two patients had a minor rent in the diaphragm; however, suturing was not required and it settled with conservative management. One patient required redo open decortication due to inadequate drainage by VATS. The average length of postoperative stay was 10 days. Patients had good pain relief by analgesia provided by nonsteroidal anti-inflammatory drugs, opioids, and epidural analgesia in select cases.

DISCUSSION

Empyema encompasses a wide spectrum of inflammatory manifestations, ranging from thin parapneumonic pleural effusion to the formation of a thick, constricting ring, which does not allow the lung to reexpand. Empyema is classified according to the clinical stage of the disease by the American Thoracic Society staging; Stage I is exudative, Stage II is fibrinopurulent, and Stage III is organizing.[4] Although there are various modalities for treatment of this condition such as antibiotics, thoracocentesis with or without ultrasound guidance, chest drain insertion with or without fibrinolytics, VATS, minithoracotomy (muscle sparing), lateral thoracotomy with decortication, and lobectomy or a pneumonectomy, each modality has a specific role to play according stage in which disease presents. The ideal definitive treatment of this suppurative process continues to be an early evacuation of pus.[5] This can be done by insertion of ICD tube early in the stage of the disease. If the suppurative process leads to fibrosis and loculations, decortication is needed to effectively clear the pus from the pleural cavity.

Decortication essentially means the removal of the restrictive fibrous layer over parietal and visceral pleura allowing the lung to reexpand. Conventionally, only children with empyema who had inadequate lung expansion by tube thoracostomy were candidates for surgical intervention.[56] However, VATS has emphasized surgery as the primary treatment modality for patients of empyema without prior drainage using tube thoracostomy. It has been proven that the earlier the intervention and debridement the better are the results.[578] Hence, primary VATS is favored over secondary procedure due to superior results. As management protocols are evolving, earlier referral by pediatricians is resulting in larger number of patients undergoing primary surgery rather than a tube ICD and secondary VATS. This has resulted in less complications, open thoracotomies, and lung resections.[5] As the skills in thoracoscopic surgery advances, more children are getting benefitted by VATS with decreasing the number and size of ports.

Maskell et al.[9] have shown from a randomized controlled trial (RCT) in adults have shown fibrinolytic therapy alone to be ineffective and to be associated with increased morbidity and mortality. Apart from the disadvantages, its use should be restricted to localized collection, where it will be most effective. Operative mechanical debridement has been increasingly challenged by chemical debridement. Both VATS and fibrinolysis have been shown to be superior to chest tube drainage alone, in retrospective and prospective studies.[10] Two prospective RCTs compared fibrinolysis to VATS in children and showed comparable results between the two treatment modalities.[1112] However, in our experience, fibrinolytics involve higher cost of treatment as well as increased risk of bleeding and inadequate clearance. In our setup, the cost of fibrinolytics such as streptokinase (approximately INR 2500–5000/1.5 IU vial), urokinase, or alteplase far exceeds that of surgery (VATS and open decortication). Hence, we reserve fibrinolytics for selected patients with localized disease.

In one of the largest RCTs in children, VATS was compared with chest drainage and intrapleural fibrinolytic therapy and a failure rate of 16.6% was reported in each arm.[13] The authors concluded that VATS was not recommended in children because it offered no therapeutic advantage over the simpler and cheaper alternative of chest drain and urokinase. However, the cost of fibrinolytics in our setup far exceeds that of primary surgery, and as the results were comparable in both the arms in this trial, VATS has been favored as the primary modality of treatment of childhood empyema over intrapleural fibrinolytics.

In response to the above study, one of the largest studies conducted in the United Kingdom by Bishay et al.,[14] 114 children underwent VATS performed by pediatric surgeons experienced in thoracoscopic surgery. They concluded that VATS has a very good outcome in childhood empyema and it has an important role in the management of this condition.

The mean age of patients and age and sex distribution were comparable in the two studies. However, the mean duration of stay was higher as a significant number of patients had preoperative insertion of ICD tube with subsequent delayed referral. We also encountered a higher number of cases with air leaks, which were self-limited and did not require a separate procedure for its management. Furthermore, we had significantly less number of patients converted to open decortication. This can be attributed to use of interchangeable camera ports and use of direct open instruments, which allow significantly better dexterity and better clearance of pleural peel in limited space. In our study, we were able to operate a higher number of patients primarily without prior chest tube drainage which gave the added advantage of clear surgical fields and a shorter duration of total hospital stay contributing to decreased surgical morbidity. In our experience, primary VATS showed better results compared to secondary VATS in terms of blood loss, air leak, and conversion to open procedures.

Single-port technique for the treatment of empyema in children is called single-port thoracoscopy and has been described by Martínez-Ferro et al. in ten consecutive patients. It was found to be safe and effective in children with better cosmetic results.[15] However, it has not achieved enough popularity as yet and technical difficulties with learning curve still exist.

CONCLUSION

Two-port VATS decortication procedure is safe, feasible, and effective.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.