Reliability of indocyanine green retention and clearance rates at 15 minutes calculated by dye-dilution cardiac output flowmetry in comparison to blood sampling in patients undergoing hepatic resection.

BACKGROUND

The indocyanine green retention rate at 15 min (ICGR15) is a marker of the liver function and is useful for planning hepatectomy. To clarify the ICGR15 and the related clearance value (ICGK) calculated by a dye-dilution cardiac output flowmetry (DCOF), we examined the correlation and clinical significance of the ICGR15 values determined by DCOF and those determined with the conventional blood sampling (BS) procedure.

METHODS

We extracted liver function parameters, including the ICGR15 modified value and ICGK, and the extent of hepatectomy from the clinical and surgical records of 63 patients with various liver diseases in whom the ICGR15 (actual value), R15m (mean), and K (clearance rate per minute) were measured by DCOF.

RESULTS

All the patients were classified as Child-Pugh grade A. Hepatic complications were observed in 10 (16%) patients, but there was no mortality. The mean values of ICGR15 determined by BS (R15-BS) and DCOF (R15-DCOF) were 12.2 ± 8.1% and 11.2 ± 8.7%, respectively. The mean R15m determined by DCOF (R15m-DCOF) was 15.7 ± 10.2%. Significant differences were observed between R15-BS and R15-DCOF (1.1 ± 4.8%; p = 0.002) and R15m-DCOF (4.0 ± 5.9%; p < 0.001). The difference between R15-BS and R15m-DCOF was greater than that between R15-BS and R15-DCOF. Correlation between R15-BS and R15-DCOF was significant r = 0.839 (p < 0.001).

CONCLUSIONS

The ICGR15 measured by DCOF shows comparable reliability and stability to the BS method, which is useful for planning hepatectomy.