The safety and efficiency of a 1470 nm laser in obtaining tract hemostasis in tubeless percutaneous nephrolithotomy: a retrospective cross-sectional study

Abstract

Objective It is challenging to perform a tubeless percutaneous nephrolithotomy (PNL) in patients with tract bleeding. The present study was designed to study the safety and efficacy of the 1470 nm laser for hemostatic completion in tubeless PNL patients with tract bleeding. Patients and Methods Between January 2020 and October 2021, 120 patients were retrospectively included and divided into two groups. The hemostasis group included 60 patients receiving tubeless PNL, in which a 1470 nm laser was used to manage tract bleeding. The other group included 60 patients receiving tubeless PNL in which the hemostasis procedure was not performed, serving as the control group. The differences in the patients’ demographic characteristics, procedural information, and posttreatment outcomes between the two groups were statistically compared. Results The differences associated with sex, age, weight, body mass index, urine culture, stone burden, calyx of puncture, degree of hydronephrosis and comorbidities between the two groups were not statistically significant. Compared with the control group, the hemostasis group showed greatly reduced blood loss (0.61 ± 0.31 vs. 0.85 ± 0.46 g/dL) and decreased postoperative hospitalization duration (2.83 ± 0.81 vs. 4.45 ± 0.91 days). The differences in operative time, stone-free rate, Visual Analogue Score and postoperative complications between the two groups were not statistically significant. In the subgroup analysis, the obese patients and patients with moderate to severe hydronephrosis in the hemostasis group also showed a significantly less blood loss (0.51 ± 0.22 vs. 0.83 ± 0.48 g/dL; 0.54 ± 0.27 vs. 0.85 ± 0.47 g/dL, respectively) and shorter length of postoperative hospitalization (2.62 ± 0.51 vs. 4.47 ± 1.19 days; 2.97 ± 0.63 vs. 4.41 ± 0.91 days, respectively) than those in the control group. Conclusions Our results demonstrated that 1470 nm laser is a safe, feasible and effective method to obtain tract hemostasis in tubeless PNL.

Comparison between contact diode laser with 980 nm and 1470 nm wavelengths for posterior laryngofissure in pigs

“…Most of the laser light is absorbed within the first 60 μm of the tissue depth. High power and the continuous mode often led to heat accumulation and more thermal damage to adjacent structures [22][23][24][25] . The lower larynx and subglottis have thick mucosa, therefore with more tissue water, resulting in greater energy dispersion and coagulation 26 .…”

“…Theoretically, the 1470 nm CDL at low power outperforms the 980 nm CDL because its absorption coefficient (μ A ) by water molecules of soft tissue chromophores is 50 times higher than 980 nm CDL. The high water μ A of the 1470 nm CDL also results in a shallow optical penetration depth (μ A = 1/μ A ) of the photons compared to the 980 nm CDL 22 , 23 . The absorptive heat level Q (J/mm 3 ) also depends on μ A, so this interaction of the energy penetration from the 1470 nm being slighter than other wavelengths results in lesser heat dispersion and accumulation.…”