A target-oriented algorithm for maintaining serum calcium stability automatically in regional citrate anticoagulation.

BACKGROUND: Regional citrate anticoagulation (RCA) for renal replacement therapy is widely practiced in critically ill patients. However, concern exists regarding its labor-intensiveness for monitoring and the associated hypocalcemia. In this study, we provided an algorithm for prescribing RCA and evaluated its safety in patients. METHODS: During 18 hemofiltration treatments with calcium-free replacement solution, participants were randomized to receive algorithm-based or trial-and-error RCA protocol. The effluent volume, post-filter and in vivo ionized calcium (iCa), and calcium in the sera and effluents were periodically measured at an interval of 1 to 2 h. RESULTS: For patients received algorithm-based RCA protocol, no one had a serum iCa less than 0.9 mmol/L, and none needed calcium supplement adjustment to maintain serum calcium stability. For patients accepted trial-and-error protocol, all patients had a serum iCa below 0.9 mmol/L, their serum iCa and calcium levels fluctuated dramatically, and all patients need additional calcium supplement adjustment during RCA. None of the participants showed a post-filter iCa > 0.4 mmol/L. CONCLUSION: We provided a safe algorithm for calculating calcium supplementation doses that could maintain serum calcium stability without additional adjustment during RCA.

Ultrasound-guided proximal versus distal axillary vein puncture in elderly patients: A randomized controlled trial.

BACKGROUND: Ultrasound-guided axillary vein catheterization is now widely used in hospital, but it remains uncertain whether the distal axillary vein approach is more beneficial for seniors than the proximal axillary vein approach. This study aims to compare the puncture success rate and anatomical characteristics between these two approaches. METHODS: Senior patients requiring central venous catheterization were enrolled and randomized to the proximal axillary vein group (n = 49) or the distal axillary vein group (n = 50). Proximal axillary vein and distal axillary vein location time, venous depth, maximum diameter, and collapse index (defined as the percentage change in vein width caused by respiration) were recorded for all patients. The rate of puncture success and operation time were compared between groups. RESULTS: Mean venous depth was 1.93 ± 0.45 cm for proximal axillary vein and 1.79 ± 0.46 cm for distal axillary vein (p < 0.001). Maximum diameter was 0.80 ± 0.33 cm for proximal axillary vein and 0.61 ± 0.33 cm for distal axillary vein (p < 0.001). Collapse indices were 20% ± 27% and 56% ± 34%, respectively (p < 0.001). Also, location time was significantly shorter for proximal axillary vein than for distal axillary vein (p < 0.001). One attempt and overall success rates were significantly higher in the proximal axillary vein group, compared with the distal axillary vein group (71.4% vs 42.0%, p = 0.003; 79.6% vs 54.0%, p = 0.007). CONCLUSION: For catheterization under ultrasound guidance in elderly patients, the proximal axillary vein approach is superior to the distal axillary vein approach.