Hypotension following Patent Ductus Arteriosus Ligation: The Role of Adrenal Hormones

Abstract

Objective To test the hypothesis that an impaired adrenal response to stress might play a role in the hypotension that follows patent ductus arteriosus (PDA) ligation. Study design We performed a multicenter study of infants born at <32 weeks gestation who were about to undergo PDA ligation. Serum adrenal steroids were measured three times: before and after a cosyntropin (1.0 microgram/kg) stimulation test (performed prior to the ligation), and at 10–12 hours after the ligation. A standardized approach for diagnosis and treatment of postoperative hypotension was followed at each site. A modified Inotrope Score (1 x dopamine (μg/kg/min) + 1 x dobutamine) was used to monitor the catecholamine support an infant received. Infants were considered to have catecholamine-resistant hypotension if their highest Inotrope Score was >15. Results Of 95 infants enrolled, 43 (45%) developed hypotension and 14 (15%) developed catecholamine-resistant hypotension. Low post-operative cortisol levels were not associated with the overall incidence of hypotension following ligation. However, low cortisol levels were associated with the refractoriness of the hypotension to catecholamine treatment. In a multivariate analysis: the odds ratio for developing catecholamine-resistant hypotension was OR=36.6, CI=2.8–476, p=0.006. Low cortisol levels (in infants with catecholamine-resistant hypotension) were not due to adrenal immaturity or impairment; their cortisol precursor concentrations were either low or unchanged and their response to cosyntropin was similar to infants without catecholamine-resistant hypotension. Conclusion Infants with low cortisol concentrations following PDA ligation are likely to develop postoperative catecholamine-resistant hypotension. We speculate that decreased adrenal stimulation, rather than an impaired adrenal response to stimulation, may account for the decreased production.

Adrenocortical insufficiency and refractory hypotension in preterm infants

“…These patients have poorer outcomes with increased severity of postoperative illnesses, and greater requirement of inotropic and respiratory support 21–23. Both inadequate adrenal stimulation23 and impaired adrenocortical response to surgical stress21 have been implicated to be responsible for this phenomenon. However, prophylactic preoperative corticosteroids are not advisable to be given as a routine, as only a small proportion of patients may genuinely benefit from this treatment 22…”

Evidence-based versus pathophysiology-based approach to diagnosis and treatment of neonatal cardiovascular compromise

“…Up to 10e30% of patients undergoing ligation develop hypotension following surgery [49,50]. The etiology of the circulatory compromise is multifactorial.…”

“…Cardiac dysfunction characterized by poor myocardial performance and decreased contractility is one of the underlying causes in a number of patients [51,52]. In this group, the most widely used vasopressor-inotrope, dopamine, appears to be effective in improving the circulatory compromise [50,53]. Prophylactic use of milrinone in a subset of patients with CO < 200 mL/kg/min has been reported to reduce post-ligation hypotension compared to historical controls [54].…”

“…Unfortunately, pre-ligation assessment of adrenal function does not identify this group of patients. However, low serum cortisol levels a few hours after ligation may be helpful in identifying the patient with relative adrenal insufficiency who might benefit from steroid administration [50,53].…”

Risk Factors for Postoperative Cardiopulmonary Instability Following Ligation of Patent Ductus Arteriosus in Very Low Birth Weight Infants

“…본 . PLCS는 수술 후 혈압상승제가 요구되는 저혈압 및 호흡부전을 특징으로 하며 보통 수술 후 6시간에서 24시간 사이 에 발생하고 약 50%까지의 빈도로 보고되고 있다 6,7,18,19) . …”