Absorption rate of subcutaneously infused fluid in ill multimorbid older patients

Abstract

Background Subcutaneous (SC) hydration is a valuable method for treating dehydration in the very old patients. Data are absent on the absorption rate, and the availability of SC infused fluid in the circulation in this group of patients where SC hydration is particularly relevant. Methods We performed an explorative study on ill very old (range 78–84 years old) geriatric patients with comorbidities who received an SC infusion of 235 ml isotonic saline containing a technetium-99m pertechnetate tracer. The activity over the infusion site was measured using a gamma detector to assess the absorption rate from the SC space. The activity was measured initially every 5 minutes, with intervals extended gradually to 15 minutes. Activity in blood samples and the thyroid gland was measured to determine the rate of availability in the circulation. Results Six patients were included. The mean age was 81 years (SD 2.1), the number of comorbidities was 4.6 (SD 1.3), and the Tilburg frailty indicator was 3.8 (SD 2.4). When the infusion was completed after 60 minutes, 53% (95% CI 50–56%) of the infused fluid was absorbed from the SC space, with 88% (95% CI 86–90%) absorbed one hour later. The absorption rate from the SC space right after the completion of the infusion was 127 ml/h (95% CI 90–164 ml/h). The appearance of the fluid into the blood and the thyroid gland verified the transfer from SC to circulation. Conclusion This first explorative study of absorption of SC infused fluid in the very old found an acceptable amount of fluid absorbed from the SC space into the circulation one hour after infusion had ended. Results are uniform but should be interpreted cautiously due to the low sample size. Trial registration ClinicalTrials.gov Identifier: NCT04536324.

New horizons in the diagnosis and management of dehydration

“…Absorption was measured using a gamma detector at the infusion site as well as peripheral blood sampling. At 60 minutes, 53% (95%CI 50–56) had been absorbed into circulation and at 110 minutes 88% (95%CI 86–90) had been absorbed, giving an average absorption rate of 127 ml/hour (95% CI 90–164 ml/hours) [ 14 ]. This was a small study, but with a clinically relevant cohort.…”

Eficácia da hipodermóclise no cuidado paliativo em enfermarias de clínica geral

“…(2022) 15 Elucidar quando a hidratação SC pode ser relevante e potencialmente orientar os médicos no planejamento do tratamento de hidratação do paciente idoso.…”

“…(2022) 15 Participaram da pesquisa seis pacientes, sendo três homens e três mulheres, com média de idade de 81 anos, tinham em média 10 medicamentos prescritos antes da admissão. Receberam uma infusão SC de 235 ml de solução salina isotônica contendo um marcador de pertecnetato de tecnécio-99m.…”