Block for uniportal video-assisted thoracoscopic surgery: an ultrasound-guided, single-penetration, double-injection approach.

Editor—For selected surgical procedures, the use of peripheral regional anaesthetic blocks may avoid general anaesthesia and increase the efficiency of the surgical pathway. However, evidence on peripheral truncal anaesthetic blocks is scarce. Even though non-intubated video-assisted thoracoscopic surgery (VATS) has been reported under local anaesthesia showing safety, feasibility and favourable results, suboptimal anaesthetic status still occurs withmoderate pain during surgery. For uniportal VATS, we would like to report two cases based on approval from the institutional review board, where we introduced an ultrasoundguided peripheral truncal anaesthetic block combining serratus plane block and intercostal nerve block. Two ASA II (hypertension history) male patients (57 years old, 65 kg and 74 years old, 81 kg respectively) underwentwedge resection of the pulmonary nodule(s) through uniportal VATS. They refused tracheal intubation and neuraxial techniques, so loco-regional anaesthesia with sedation was proposed. Under standard monitoring, they were positioned in a full lateral decubitus position with the operative side up (Fig. 1). Intravenous (iv) fentanyl (2 μg kg) and midazolam (0.02 mg kg) were given for sedation. By targeting the neurovascular bundle in the cross-sectional view obtained by a linear transducer (Fig. 1 and ), 20 ml of local anaesthetic (LA; 0.5% ropivacaine with 1:400 000 epinephrine) was used for the first injection (serratus plane block) (Fig. 1) and another 10 ml for the second injection (intercostal nerve block) (Fig. 1) from the same penetration point after confirmation by nerve stimulation. Ipsilateral vagal and phrenic blocks were done at neck level to prevent coughs and reduce diaphragmatic movement. Opening pressures were tested before every injection to prevent intrafascicular spread. Sedation was maintained intra-operatively by target-controlled infusion with propofol (Schnider Ce, 2–3.5 μg ml). After skin incision, but before entering the pleura, the surgeon was asked to inject 5 ml LA into the parietal pleura, after which open pneumothorax was created. Oxygen saturation was >92%, with spontaneous breathing through a face mask throughout the procedure. The surgical procedures were uneventful, without patient movement or top-up anaesthetic, and were completed within 2 h. At the end of the operation, the collapsed lung was re-inflated by a face mask. The reasons for choosing injection below (in between the serratus and rib) the serratus anterior to accomplish serratus plane block are 3-fold. First, considering lateral cutaneous branches of the intercostal nerves, either from the indicated or adjacent level, run in an outward direction in the mid-axillary line, below-theserratus injection covers all the soft tissues superficial to the ribs (Fig. 1 and ). Second, below-the-serratus injection distributes more anteriorly, better fitting the anterolateral incision site. Third, finding the ribs is easier and more consistent than using the serratus as a landmark. The round hyperechoic structure (Fig. 1 and ) is likely the neurovascular bundle, because usually it has left the subcostal groove in the mid-axillary line and can travel to the middle of the intercostal space, verified by randomly dissecting two cadavers in our work (Fig. 1 ). Vagal blockade was achieved at the neck level because the left-sided vagus nerve is sometimes difficult to visualize within the thorax, and the act of exploring the vagus nervemay induce coughs before intrathoracic vagal blockade is accomplished. In combination with phrenic nerve blockade achieved via injection over the surface of the scalenus anterior at the interscalene level, the two blocks can be easily done as another single-penetration double-injection technique in the neck. In conclusion, we propose an easy ultrasound-guided peripheral truncal anaesthetic block for uniportal VATS. A prospective trial (TMU-JIRB 201504056) is going to be conducted to clarify the details of VATS block.