Improved oxidative status in major abdominal surgery patients after N-acetyl cystein supplementation.

BACKGROUND: Increased levels of reactive oxygen species during and after surgery may affect inflammatory response, post-operative adhesion molecule formation, and hemodynamic stability. The glutathione redox cycle is an important regulator in oxidative stress and its reduced forms scavenge free radicals. N-acetyl cysteine, a precursor of reduced glutathione, is considered as a potentially therapeutic wide spectrum agent in clinical practice. We therefore examined whether N-acetyl cysteine improves some biochemical parameters in cancer patients undergoing major abdominal surgery. METHODS: Thirty-three patients diagnosed with pancreas, stomach, rectum, colon malignancies, and undergoing major abdominal surgery at Ankara Numune Training and Research Hospital were randomly divided into two groups; control (CON) and N-acetyl cysteine (NAC). The NAC group had 1,200 mg N-acetyl cysteine starting two days before the operation day, in addition to isonitrogenous and isocaloric total parenteral nutrition of 1.2 g/kg protein, 25 kcal/kg, and 60:40 carbohydrate/fat ratio. Blood and urine samples were drawn two days before the operation, on operation day, and on the first, third, and fifth days post-operation. RESULTS: Plasma malondialdehyde was significantly lower in the NAC group (P < 0.001). N-acetyl cysteine treatment did not affect plasma levels of vitamin A, C or E. The NAC group exhibited a higher ratio of reduced glutathione to oxidised glutathione (P = 0.019). Urinary nitrate level was also significantly lower in the NAC group (P = 0.016). CONCLUSION: The study demonstrated the clinical importance of N-acetyl cysteine supplementation on antioxidant parameters in abdominal surgery patients. In these patients N-acetyl cysteine and vitamin administration can be considered as an effective method for improvement of oxidative status.

[The role of nitric oxide in trauma and infection]. / Travma ve enfeksiyonda nitrik oksidin rolü

Nitric oxide (NO) is a very important molecule for homeostasis. It is involved in several pathological conditions ranging from hypertension to septic shock. It is synthesized from L-arginine, which is catalyzed by nitric oxide synthase (NOS). Both constitutional and inducible NOS are involved in NO synthesis. While NO produced by constitutional NOS is required for normal physiologic processes, excessive production by inducible NOS results in injury and tissue damage. Induced NO may be either protective or damaging in acute inflammatory conditions. As a result of pluripotent activities, NO presents as a paradoxical phenomenon in almost all conditions in which confusing aspects arise concerning the pathophysiology. This article reviews the role of NO in trauma and infections.