Bronchoscopy-Based Approach Enhances Central Line Insertion Accuracy compared toTraditional Methods, finds study

It is crucial to have the central venous catheters (CVCs) properly inserted to ensure effective treatment and reduce risks of complications such as vascular injury, cardiac tamponade, or atrial fibrillation. Different methods have been utilized to estimate the accurate depth of CVC insertion, each method having its own constraints. Typically, the carina seen on the preoperative chest X-ray is used as a landmark for determining the depth of CVC insertion . Recent research study evaluated a bronchoscopy-based technique for predicting the depth of insertion of central venous catheters (CVCs) compared to the Peres' formula-based method in adult patients undergoing cardiac surgery. The study included 81 patients who were randomized into a bronchoscopy group or a Peres' formula group. In the bronchoscopy group, the depth of CVC insertion was determined by measuring the distance from the carina (identified by a flexible bronchoscope) to the proximal end of the tracheal tube, minus the distance from the skin insertion reference point to the tracheal tube. In the Peres' group, the depth was calculated as height (cm)/10.

Results

The primary outcome was the proportion of correct CVC placements, defined as the distal tip being positioned between 2 cm proximal to 1 cm distal to the superior vena cava-right atrium junction. The secondary outcomes were the alignment of the CVC tips and the correlation between the bronchoscopy-measured depth and the radiology-measured depth.

The results showed that a significantly higher proportion of CVCs were placed correctly in the bronchoscopy group compared to the Peres' group (87.8% vs 37.5%, p=0.001). The mean depth of CVC insertion was also significantly different between the two groups (14.8 cm in the bronchoscopy group vs 15.8 cm in the Peres' group, p=0.002). Additionally, a higher proportion of CVC tips were found to be abutting the vessel wall in the Peres' group compared to the bronchoscopy group (45% vs 19.5%, p=0.014).

Findings

The researchers also found a significant difference between the bronchoscopy-measured depth and the radiology-measured depth, with the bronchoscopy method resulting in a deeper CVC insertion by about 1.6 cm.

Conclusion

In conclusion, the bronchoscopy-based carinal measurement technique was superior to the Peres' formula-based method in predicting the depth of CVC insertion in adult cardiac surgery patients. The bronchoscopy method resulted in more accurate CVC placements with better alignment of the catheter tips.

Key Points

1. The study evaluated a bronchoscopy-based technique for predicting the depth of insertion of central venous catheters (CVCs) compared to the Peres' formula-based method in adult patients undergoing cardiac surgery.

2. The study included 81 patients who were randomized into a bronchoscopy group or a Peres' formula group. In the bronchoscopy group, the depth was determined by measuring the distance from the carina to the proximal end of the tracheal tube, minus the distance from the skin insertion point to the tracheal tube. In the Peres' group, the depth was calculated as height (cm)/10.

3. The primary outcome was the proportion of correct CVC placements, defined as the distal tip being positioned between 2 cm proximal to 1 cm distal to the superior vena cava-right atrium junction. The secondary outcomes were the alignment of the CVC tips and the correlation between the bronchoscopy-measured depth and the radiology-measured depth.

4. The results showed that a significantly higher proportion of CVCs were placed correctly in the bronchoscopy group compared to the Peres' group (87.8% vs 37.5%, p=0.001). The mean depth of CVC insertion was also significantly different between the two groups (14.8 cm in the bronchoscopy group vs 15.8 cm in the Peres' group, p=0.002).

5. A higher proportion of CVC tips were found to be abutting the vessel wall in the Peres' group compared to the bronchoscopy group (45% vs 19.5%, p=0.014).

6. The researchers found a significant difference between the bronchoscopy-measured depth and the radiology-measured depth, with the bronchoscopy method resulting in a deeper CVC insertion by about 1.6 cm.

Reference –

Misra S, Das PK, Behera BK, Das D,Patra TK. Predicting the depth of insertion of central venous catheters using a bronchoscopy‑based carinal measurement technique or the Peres’ formula‑based method in adults undergoing cardiac surgery: A randomised comparative double‑blind study. Indian J Anaesth 2024;68:978‑84