Sir,Catheter malposition is a known complication of central venous catheterisation, with incidence of less than 1% to above 60%.[1] Misplacement is more frequent after the right subclavian (SCV) than the right internal jugular vein (IJV) approach. However, catheterisation via the left IJV results in more malpositions and vascular perforations than catheter placement through the right IJV.[1]We discuss a case of a 1-month-old baby (length 57 cm, weight 4.8 kg) undergoing decompressive craniotomy for acute subdural haematoma. A 4,5 Fr multicath (Vygon Gmb H and Co. KG, Germany) central line was inserted in the right IJV for intra-operative central venous pressure monitoring. The catheter was inserted using the anatomic landmark technique and was fixed at the 7 cm mark on the skin after confirming backflow in all the lumens. Post-central line, chest roentgenogram (CXR) showed the tip of the catheter in the right subclavian vein by about 2.5 cm [Figure 1a]. Because it was difficult to reposition the original line, we planned ultrasound (USG)-guided left IJV cannulation. The J-tip of the guidewire was directed caudally and towards the right. The catheter was fixed at the 6 cm mark on the skin. Check CXR showed the catheter going to the right innominate vein by 1 cm [Figure 1b]. The catheter was refixed after pulling it out by 1 cm, and a repeat CXR confirmed its correct placement.
Figure 1
Chest roentgenogram (CXR) showing the tip of the catheter in (a) the right subclavian vein by about 2.5 cm and (b) the right innominate vein by 1 cm
Chest roentgenogram (CXR) showing the tip of the catheter in (a) the right subclavian vein by about 2.5 cm and (b) the right innominate vein by 1 cmImage-guided (USG) vascular access technique increases the likelihood of achieving access, especially in the obese and in the paediatric populations, where anatomic localisation may be difficult.[2] It is associated with fewer complication rates and a probable improvement in long-term venous patency rates. In paediatric patients, meticulous attention in catheter positioning is important to ensure that the lines are kept functional for longer periods. Although the USG-guided technique is useful for initial localisation of the vein, it does not guide about the length of the catheter to be inserted. Directing the J-tip of the catheter caudally increases the correct placement of the central venous catheters into the right atrium.[3] But, this is more useful in SCV than in IJV cannulation.Overinsertion of the catheter may be the cause of misplacement in our case. This is especially important in small children where increased intravascular catheter length may result in complications like vascular erosions and pericardial tamponade. Various techniques described for guiding the depth of insertion include transesophageal echocardiography (TEE) and formulas using patient characteristics (age, height, weight). However, TEE is not feasible in such small infants and ECG-guided central venous cannulation is cumbersome. The optimal size of the catheter in our case would be 3 or 4 Fr, and the optimal length of insertion should have been 4.5 cm according to height (catheter length=height in cm/10-1) and 5 cm according to the weight (<4.9 kg).[4] This must be followed by a radiological confirmation of the position of the catheter tip.
Figure 1