High pre-operative urinary norepinephrine is an independent determinant of peri-operative hemodynamic instability in unilateral pheochromocytoma/paraganglioma removal.
BACKGROUND
Peri-operative hemodynamic instability (HDI) may increase peri-operative morbidity in pheochromocytoma/paraganglioma (PPGL) patients.


OBJECTIVE
This study aimed to determine which tumor-related risk factors could lead to peri-operative HDI in unilateral or single PPGL removal.


METHODS
Before surgery, 66 PPGL patients had at least two sets of 24 h urine collected for fractionated catecholamine analysis. At surgery, an arterial line was inserted to record systolic blood pressure (SBP), diastolic BP, and mean arterial BP (MAP). Peri-operative HDI was defined as hypertension (SBP > 160 mmHg) and/or hypotension (SBP < 90 mmHg and/or MAP < 60 mmHg) for >10 consecutive minutes either intra-operatively or within the first 12 h after surgery. Urinary fractionated catecholamines and other variables were compared between those with peri-operative HDI (group I) and those without (group II).


RESULTS
A total of 15 (22.7 %) patients belonged to group I, while 51 patients belonged to group II. One (1.5 %) patient died 9 days after surgery. Relative to group II, group I had significantly higher urinary norepinephrine (NE) (5,488.0 vs. 1,980.0 nmol/L, p < 0.001), urinary normetanephrine (5,130.9 vs. 3,853.4 nmol/L, p = 0.045), maximum SBP at operation (188.2 vs. 167.4 mmHg, p = 0.037), but lower MAP after operation (78.9 vs. 91.8 mmHg, p = 0.026). Urinary NE (OD 1.02, 95 % confidence interval [CI] 1.01-1.03, p = 0.046) was an independent risk factor for peri-operative HDI. The urinary NE level significantly correlated with maximum intra-operative SBP and MAP (r 0.692, p < 0.001; and r 0.669, p < 0.001, respectively) and inversely correlated with maximum post-operative MAP (r -0.305, p = 0.040).


CONCLUSIONS
High pre-operative urinary NE was an independent tumor-related factor for peri-operative HDI and significantly correlated with sustained intra-operative hypertension and post-operative hypotension.
Division of Endocrine Surgery, Department of Surgery, Queen Mary Hospital, 102 Pokfulam Road, Hong Kong, SAR, China.
Rita Y K
RY
Chang
Brian Hung-Hin
BH
Lang
Kai Pun
KP
Wong
Chung-Yau
CY
Lo
D000293:Adolescent; D000310:Adrenal Gland Neoplasms / Q000503:physiopathology* / Q000601:surgery / Q000652:urine*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D062186:Arterial Pressure; D015415:Biomarkers / Q000652:urine; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D006973:Hypertension / Q000503:physiopathology / Q000652:urine; D007022:Hypotension / Q000503:physiopathology / Q000652:urine; D008297:Male; D008875:Middle Aged; D009638:Norepinephrine / Q000652:urine*; D010236:Paraganglioma, Extra-Adrenal / Q000503:physiopathology* / Q000601:surgery / Q000652:urine*; D059035:Perioperative Period; D010673:Pheochromocytoma / Q000503:physiopathology* / Q000601:surgery / Q000652:urine*; D012307:Risk Factors; D055815:Young Adult
D015415:Biomarkers; D009638:Norepinephrine