Rectosigmoid pHi monitoring during experimental necrotizing enterocolitis

Area of Science:

• Neonatal physiology
• Gastrointestinal research
• Splanchnic circulation

Background:

• Intramural pH (pHi) is a recognized indicator of splanchnic perfusion.
• Necrotizing enterocolitis (NEC) is a serious condition in neonates.
• Assessing bowel damage severity in NEC is crucial for timely intervention.

Purpose of the Study:

• To determine if rectosigmoid pHi can accurately reflect the severity of bowel damage in an experimental model of NEC.
• To investigate the sensitivity and timing of rectosigmoid pHi changes in relation to NEC progression.

Main Methods:

• 36 neonatal piglets underwent anesthesia, mechanical ventilation, and hemodynamic monitoring.
• A sigmoid tonometer was used to measure rectosigmoid intramural pH (pHi).
• NEC was induced in 27 piglets using casein-d-gluconate; 9 controls received saline. Bowel injury was graded macroscopically (0-3) and histologically (Chiu scale 0-5).

Main Results:

• Casein-injected piglets showed varying degrees of NEC (grade 1-3), while controls had normal bowels (grade 0).
• Affected bowels exhibited histological changes (Chiu scale 2-4).
• A significant, sustained drop in rectosigmoid pHi was observed in piglets with moderate to severe NEC (grade 2-3), unlike those with mild NEC or controls.

Conclusions:

• Rectosigmoid pHi drop is a sensitive and early indicator of severe ileal mucosal necrosis in this experimental NEC model.
• This suggests rectosigmoid pHi monitoring could be valuable for assessing NEC severity in neonates.