Patients in the experimental group will receive the erector spinae catheter prior the surgery and will be administered local anesthetics for 48 hours post-operatively.

Anesthetic regimen: initial bolus of 20ml 0.5% levobupivacaine before the end of surgery. Then continually ropivacaine 0,2% 5ml/h with intermittent boluses 15ml ropivacaine 0,2% every 4h.

Both groups will receive multimodal analgetic treatment consisting of a patient-controlled (PCA) pump with opioid analgetics and a peripherally acting analgetic metamizol on a regular basis. The PCA pump will be set to intermittent boluses of 3mg piritramide with a lock-out time 15 min and a maximal number of 6 boluses /3 hours. Patients will receive metamizol 2,5g/12hours i.v. on the day of surgery and 500-1000mg / 6 hours orally on the first and second post-operative day.

Patients will receive standard treatment, i.e. the multi-level intercostal block administered at the end of the surgery by the surgeon. They will receive 20ml 0,5% levobupivacaine on 6 levels of the thoracic wall according to the operative wound level.

Both groups will receive multimodal analgetic treatment consisting of a patient-controlled (PCA) pump with opioid analgetics and a peripherally acting analgetic metamizol on a regular basis. The PCA pump will be set to intermittent boluses of 3mg piritramide with a lock-out time 15 min and a maximal number of 6 boluses /3 hours. Patients will receive metamizol 2,5g/12hours i.v. on the day of surgery and 500-1000mg / 6 hours orally on the first and second post-operative day.

Patients in the experimental group will receive the Erector Spinae Catheter with an initial bolus ob 20ml 0,5% levobupivacaine prior the surgery and will be administered local anesthetics for 48 hours post-operatively.

Investigators will measure the total consumption of i.v. piritramide after surgery given by the PCA (patient-controlled analgesia) pump. The PCA pump automatically marks all the drug consumption. The PCA pump will be set to a uniform protocol: piritramide 1mg/ml; flow 0ml/h, bolus 3ml, lockout time 15 min, max 4 boluses / hour.

Investigators will compare the change between pre- and post-operative main inspiratory pressure and main expiratory pressure measurements between the two research groups.

Investigators will compare the change between pre- and post-operative main inspiratory pressure and main expiratory pressure measurements between the two research groups.

Investigators will measure subjective perception of pain with the nubmering rating score (NRS) scoring system at resting and coughing. The NRS scoring system is a numerical scale from 0-10, with 0 being no pain and 10 the strongest pain imaginable. Patients will assess their pain with the help of analogue scale with colours and faces by each number representing different NRS pain levels.

Investigators will follow up the patients in 4 and 12 weeks after surgery for possible complications. The complications will be read from the follow up documentation in observed patient files. Investigators will search for complications such as arrhythmias, lung or wound infections, lethalities or other unexpected complications.