Historical Background
In 1910, a Swedish internist, Hans Jacobaeus, reported the use of Nitze’s lighted cystoscope in the pleural space under local anaesthesia using a heated wire to divide the adhesions. This intrapleural pneumolysis was quite successful in achieving pulmonary collapse, with a relatively low morbidity and mortality. This technique was soon adopted in Europe and in the USA. Jacobaeus reported the use of this technique to diagnose benign and malignant conditions of the pleura and lung parenchyma in 1921. Then with the advent of new antibiotics for tuberculosis, the role of surgery for lung and pleural disorders diminished. The popularity of the technique was then revived in the 1970s, when it was found to be an accurate method for obtaining lung biopsies for diagnosing Pneumocystis carinii pneumonia in immunocompromised children. Rogers was the earliest advocate of this technique for children in North America in 1976. The introduction of laparoscopic cholecystectomy in 1988 led to an explosive increase in the use of minimal access surgery for different conditions. There has been a true rebirth of thoracoscopy in the last ten to fifteen years, and it is now currently accepted and used by an increasing number of practicing paediatric surgeons for a variety of indications.

Indications for Thoracoscopy
VATS can be performed for the following conditions:

Diagnostic
	Lung biopsy and wedge resection
		Interstitial lung disease (ILD)
		Biopsy of pulmonary nodule
		Metastatic disease
		Inflammatory disease
	Biopsy and resection of mediastinal lesions
		Lymphoma
		Thymic and thyroid lesions
		Cystic hygromas
		Foregut duplications
		Ganglioneuromas and neuroblastomas
Therapeutic
	Pleural conditions
		Spontaneous pneumothorax
		Empyema Thoracis (ET)
		Chylothorax
	Extensive pulmonary resections, including segmentectomy and lobectomy for
		Infectious diseases
		Cavitatory lesions
		Bullous disease
		Sequestrations
		Lobar pneumonia
		Congenital adenomatoid malformations
		Neoplasms
	Other advanced intrathoracic procedures
		Patent ductus arteriosus (PDA) closure
		Division of Ligamentum in the Vascular Ring
		Repair of hiatus hernia and other diaphragmatic defects
		Oesophageal myotomy for achalasia
		Anterior spinal fusion
		Repair of oesophageal atresia
		Excision of benign oesophageal tumours
		Repair of pectus excavatum
		Sympathectomy
		Pericardial window for pericardial effusion
		Trans-diaphragmatic adrenal surgeryContraindications
Contraindications
	Late stages of empyema after the development of fibrosis with severe crowding of ribs (without any obvious space between ribs).
	Densely adherent tumour infiltrating chest wall.

Preoperative Preparation
Most intrathoracic lesions require routine roentgenograms as well as CT scans. The CT scan defines the extent of disease precisely and helps in planning of surgery. Some procedures needs the specific measures preoperatively and are mentioned in the operative technique for the individual disease. In few patients’ ultrasound to know the contents whether solid or liquid and bronchoscopy may be required. The patients should be fully worked up for general anaesthesia with blood grouping and cross matching. The patients should be taught breathing exercises, which is continued post operatively to hasten the recovery.

Anaesthesia
The working space in thorax is created by giving collapsing the ipsilateral lung. There are many different modalities to collapse the ipsilateral lung, including placement of endotracheal tube in the contralateral main stem bronchus, use of double lumen tube, double lumen endobronchial tubes, use of bronchial blockers1 and use of low pressure CO2 insufflations. The application of general anaesthesia using single lung ventilation may be technically difficult in small children. The smallest double-lumen device is suitable for a child with a body weight of at least 30 to 35 kilograms. Alternative techniques like selective intubation of main stem bronchus with a cuffed or uncuffed tube can be used in small children. Insufflation of carbon dioxide under positive pressure can result in haemodynamic compromise and is not well tolerated by small infants. Tension pneumothorax decreases cardiac index, mean arterial pressure and left ventricular stroke index, and increases pulmonary artery and central venous pressures.2 In younger children, an intraoperative endobronchial blockage (using a Fogarty catheter) can be carried out to achieve the selective ventilation.1

Surgical Technique
For VATS in children, 5 mm and 10 mm telescopes are used. In small infants, 3.5 mm or the new 14-gauge endoscopic telescope may be useful. The standard trocars and hand instruments used in laparoscopy (10, 5 and 3 mm) can be used; however short trocars without valves and special instruments designed for VATS, which can be inserted through an open incision and have gentle “S” shaped curve to adapt to the shape of the thoracic cage can be used.

Decortications for Empyema Thoracis
Early intervention of emyema prevents chronicity of the disease. In the exudative stage (48-72 hours) (7-10 days) the management with intercostal drain is adequate. However, in the fibrino-purulent stage ICD is not adequate to evacuate empyema completely and VATS should be performed. The advantage of VATS in empyema thoracis includes determining stage of the disease, breaking of all loculi, evacuation of thick pus and fibrinopurulent material, reduction in bacterial load and insertion of ICD in the dependant position. As thick pus and fibrinopurulent material is removed thoroughly, the fever resolves quickly (usually 48-72 hours), ICD is required for short duration (usually 48-72 hours) and post procedure hospitalisation can be reduced to 6-7 days.3-4 In addition trauma of insertion of ICD under local anaesthesia is avoided. The disadvantages are need of general anaesthesia, operating room with

Pulmonary Parenchymal Biopsy
Pulmonary biopsies for either diffuse or localized processes are common indications for thoracoscopy. In patients with diffuse processes, preoperative imaging with postero-lateral and lateral chest roentgenograms is usually sufficient. In patients with localized disease processes, preoperative imaging with high resolution CT scans is useful. Thoracoscopic sampling of pulmonary tissue gives a very high yield and results are encouraging.5,6

Mediastinal Disease
Mediastinal lymphnodes biopsy and excision of other mediastinal lesions can be performed easily. Extensive surface biopsy specimens can be done using cup forceps, while deeper tissue can be obtained with a transthoracic, visually guided, true-cut needle. Thymus gland is located in the superior mediastinum and its excision is indicated in some of the patients with Myasthenia Gravis. The techniques of VATS can be safely applied in these patients to decrease the morbidity of the thoracotomy.7

Diaphragmatic Eventeration and Hernia
The repair of the diaphragmatic hernia and eventeration is relatively straight forward operations even in small children. The recovery is rapid with removal of ICD in 48 hours with early discharge from the hospital.8

Other conditions
The division of PDA can be performed using VATS.9 Similarly it is possible to clip and divide the ligamentum of the vascular ring using VATS. Spontaneous pneumothorax in young adults is caused by apical bullae and primary VATS with the stapling can be performed.10 Benign oesophageal tumours like leiomyoma cab be removed using VATS with good results.12 The VATS application has been used successfully with good results in newborn with oesophageal atresia and tracheo-oesophageal fistula.13,14

Summary
VATS is a useful for the diagnosis and treatment of many intrathoracic conditions for which in past conventional thoracotomy was performed. The same results can be achieved without thoracotomy with less surgical trauma, reduced hospitalization and speedier return to normal physical activities.

References

1. Shah RS, Varela P J, Merry C M. Selective Ventilation Using A Fogarty Balloon Catheter as A Bronchial Blocker: An Essential Technique for Paediatric Thoracoscopic Surgery. Paediatric Endosurgery and Innovative Techniques 1997; 1 : 147-50.
2. Hill RC, Jones DR, Vance RA, Kalantarian B. Selective lung ventilation during thoracoscopy: Effects of insufflation on haemodynamics. Ann Thorac Surg 1996; 61 : 945-48.
3. Shah RS. Empyema Thoracis - Recent Trends in the Management. Indian J Practical Pediatrics 2004; 6 : 21-6.
4. Merry CM, Bufo AJ, Shah RS, Schropp K P, Lobe TE. Early definitive Treatment in Paediatric Empyema. J Paediatric Surgery 1999;33: 178-81.
5. Piolanti M, Coppola F, Papa S, Pilotti V, Mattioli S, Gavelli G. Ultrasonographic localization of occult pulmonary nodules during video-assisted thoracic surgery. Eur Radiol 2003.
6. Blakely ML, Shah R, Lakshman S, Lezamme P, Lobe TE. “Pediatric Thoracoscopy”, In: Atlas of Videothorascopic Surgery. Di Falco G (Ed.) 1998. Milan : Masson.
7. Bufo AJ, Shah R, Wheeler T, Fachinni S, Lobe TE. Video Assisted Thymectomy in children with Myasthenia Gravis. Accepted for publication in Paediatric Endosurgery and Innovative Techniques.
8. Hwang Z, Shin JS, Cho YH, Sun K, Lee IS. A simple technique for the thoracoscopic plication of the diaphragm. Chest 2003; 124 : 376-8.
9. Nezafati MH. Closure of patent ductus arteriosus by video-assisted thoracoscopic surgery; minimally invasive, maximally effective: report of 600 cases. Heart Surg Forum 2003; 6 : S28.
10. Galbis Caravajal JM, Mafe Madueno JJ, Benlloch Carrion S, Baschwitz Gomez B, Rodriguez Paniagua JM. Video-assisted thoracoscopic surgery in the treatment of pneumothorax: 107 consecutive procedures. Arch Bronconeumol 2003; 39 : 310-3.
11. Hazama K, Akashi A, Shigemura N, Nakagiri T. Less invasive needle thoracoscopic laser ablation of small bullae for primary spontaneous pneumothorax. Eur J Cardiothorac Surg 2003; 24 : 139-44.
12. Samphire J, Nafteux P, Luketich J. Minimally invasive techniques for resection of benign esophageal tumors. Semin Thorac Cardiovasc Surg 2003; 15 : 35-43.
13. Krosnar S, Baxter A. Thoracoscopic repair of esophageal atresia with tracheoesophageal fistula: anesthetic and intensive care management of a series of eight neonates. Paediatr Anaesth 2005; 15 : 541-6.
14. Aziz GA, Schier F. Thoracoscopic ligation of a tracheoesophageal H-type fistula in a newborn. J Pediatr Surg 2005; 40 : 35-6.