Hemodynamic effects of orally administered delta-ALA during radical prostatectomy

PURPOSE: We investigated hemodynamics in patients receiving delta-Aminolevulinic acid (delta-ALA) to visualize tumor margins prior to radical retro pubic prostatectomy.

PATIENTS: Twenty patients undergoing elective open radical retro pubic prostatectomy (RRP).

METHODS: Cohort observational study. Ten patients receiving 20 mg/kg of delta-ALA orally prior to surgery (delta-ALA) and 10 patients undergoing RRP without the application of delta-ALA served as a retrospectively matched cohort (CONTROL).

MEASUREMENTS: Changes in heart rate (HR), mean arterial blood pressure (MAP), and functional hemodynamic parameters were assessed by electrocardiogram, non-invasive and invasive blood pressure monitoring plus transcardiopulmonary thermodilution.

RESULTS: Patients of both groups did not differ in means of age, body mass index, or ASA classification. During surgery, HR and MAP did not differ significantly between both groups. Also, the amount of IV crystalloids and colloids did not differ significantly. In contrast, the amount of vasopressor necessary to maintain MAP within the target range of 70-90 mmHg was significantly higher in delta-ALA when compared to CONTROL (0.08 ± 0.04 μg/kg/min (delta-ALA) vs. 0.03 ± 0.02 μg/kg/min (CONTROL); P < 0.01). Immediately after surgery, patients of delta-ALA showed a significantly higher heart rate (82 ± 18 min(-1) vs. 67 ± 9 min(-1); P < 0.05) compared to patients of CONTROL. Cardiac index, global end-diastolic volume index, and extravascular lung water index were significantly higher after surgery, when compared to baseline values (P < 0.05).

CONCLUSIONS: Orally administered delta-ALA prior to open radical prostatectomy induces hemodynamic instability in the perioperative period requiring vasopressor support. Further, an increase of extravascular lung water points toward an increased vascular permeability induced by delta-ALA.