Effect of intravenous atrial natriuretic peptide on gas exchange in humans

Low-dose carperitide (α-human A-type natriuretic peptide) alleviates hemoglobin concentration decrease during prolonged oral surgery: a randomized controlled study

PURPOSE

Surgical injury stimulates the renin-angiotensin-aldosterone system (RAAS) and causes antidiuresis, leading to postoperative oliguria. Carperitide (α-human A-type natriuretic peptide) is a cardiac peptide hormone secreted from the atrium. This peptide hormone enhances diuresis by suppressing the RAAS. In our experience, carperitide alleviates decreased hemoglobin (Hb) concentration during elective surgery. In the current study, we investigated the relationship between low-dose carperitide (0.01 µg/kg/min) and Hb concentration during oral surgery.

METHODS

Patients (ASA-PS: I-II, 40-80 years old) undergoing oral maxillofacial surgery (duration of operation >8 h) were enrolled in this study. Patients were divided into two groups: the carperitide group received carperitide at 0.01 µg/kg/min and the control group received normal saline. Body fluid water [including total body water (TBW), extracellular water (ECW), and intracellular water (ICW)], urine volume, and chemical parameters such as Hb concentration, PaO₂, and serum electrolytes were evaluated every 2 h.

RESULTS

In the carperitide group (n = 15), Hb decreased from 12.6 ± 1.1 to 10.8 ± 1.5 g/dl, while it decreased from 12.6 ± 1.4 to 9.5 ± 1.3 g/dl in the control group (n = 15) (p < 0.05). Urine volume (2557.3 ± 983.5 mL) in the carperitide group was significantly more than it was in the control group (1108.8 ± 586.4 mL; p < 0.001). There were no significant differences in clinical characteristics, body fluid water, PaO₂, and serum electrolytes between the two groups. In addition, there were no perioperative clinical respiratory and hemodynamic complications in the groups.

CONCLUSION

The Hb concentration in the group administered low-dose carperitide at 0.01 µg/kg/min remained higher than that in the control group during surgery. Administration of low-dose carperitide may therefore reduce the risk of blood transfusion during surgery.

The effects of atrial natriuretic peptide infusion on hemodynamic, renal, and hormonal responses during gastrectomy

Atrial natriuretic peptide (ANP) antagonizes the reninangiotensin-aldosterone, adrenocorticotropic hormone-cortisol, vasopressin, and endothelin systems. Surgical injury stimulates these systems and causes vasoconstriction and antidiuresis. We assessed the hemodynamic, renal, and endocrine effects of continuous intravenous infusion of ANP in patients anesthetized with sevoflurane undergoing gastrectomy. ANP (0.1 microgram.kg-1.min-1; ANP group, n = 9) or saline (control group, n = 9) was infused continuously for 3 h from the start of the operation. The ANP group showed much higher urinary volume and sodium, potassium, and chloride excretion than the control group, although the former had lower arterial blood pressure. ANP infusion slightly inhibited aldosterone secretion and initially tended to inhibit renin secretion stimulated by surgery, but it did not affect surgery-induced increases in the plasma concentrations of vasopressin, adrenocorticotropic hormone, cortisol, or endothelin. Two patients in the ANP group experienced excessive hypotension, one experienced bradycardia, and two experienced mild hypoxemia, which required treatment but were resolved easily. These findings suggest that ANP infusion may be used with caution for controlling renal function and arterial blood pressure during surgery.

IMPLICATIONS

Continuous intravenous infusion of atrial natriuretic peptide, 0.1 microgram.kg-1.min-1, during gastrectomy was associated with higher water and sodium excretion and lower arterial blood pressure. It tended to inhibit the renin-angiotensin-aldosterone system compared with saline infusion, which suggests that atrial natriuretic peptide may be useful for intraoperative circulation control.