Effectiveness of intravenous infusion of N-acetylcysteine in cirrhotic patients undergoing major abdominal surgeries

N-acetylcysteine in Kidney Disease: Molecular Mechanisms, Pharmacokinetics, and Clinical Effectiveness

N-acetylcysteine (NAC) has shown beneficial effects in both acute kidney disease and chronic kidney disease (CKD) in preclinical and clinical studies. Different dosage and administration forms of NAC have specific pharmacokinetic properties that determine the temporal pattern of plasma concentrations of NAC and its active metabolites. Especially in acute situations with short-term NAC administration, appropriate NAC and glutathione (GSH) plasma concentrations should be timely ensured. For oral dosage forms, bioavailability needs to be established for the respective NAC formulation. Kidney function influences NAC pharmacokinetics, including a reduction of NAC clearance in advanced CKD. In addition, mechanisms of action underlying beneficial NAC effects depend on kidney function as well as comorbidities, both involving GSH deficiency, alterations in nuclear factor erythroid 2-related factor 2 (Nrf2)-dependent signaling, oxidative stress, mitochondrial dysfunction, and disturbed mitochondrial bioenergetics. This also applies to nonrenal NAC mechanisms. The timing of preventive NAC administration in relation to potential injury is important. NAC administration seems most effective either preceding, or preceding and paralleling conditions that induce tissue damage. Furthermore, studies suggest that very high concentrations of NAC should be avoided because they could exert reductive stress. Delayed administration of NAC might interfere with endogenous repair mechanisms. In conclusion, studies on NAC treatment regimens need to account for both NAC pharmacokinetics and NAC molecular effects. Kidney function of the patient population and pathomechanisms of the kidney disease should guide rational NAC trial design. A targeted trial approach and biomarker-guided protocols could pave the way for the use of NAC in precision medicine.

The effects of N-acetylcysteine on hepatic, hematologic, and renal parameters in cirrhotic patients: a randomized controlled trial

Aim

To evaluate the effects of N-acetylcysteine (NAC) supplementation in cirrhotic patients.

Background

Chronic hepatic inflammation leads to fibrosis and cirrhosis through various mechanisms such as oxidative stress. NAC is one of the intracellular precursors of glutathione that can degrade most reactive oxygen species. Recently, the beneficial effects of NAC in animal and human studies on preventing liver injury progression and improving liver function have been examined. However, more studies on human subjects are still required.

Methods

Well-known cirrhotic patients with a specific etiology and aged 18 to 70 years who referred to the gastrointestinal clinic of Ayatollah Taleghani Hospital from December 2018 to December 2019 were enrolled in the present randomized double-blind controlled trial. Patients in the intervention group received NAC tablets at a dose of 600 mg daily, and the control group received a placebo. Demographic data, medical characteristics, and Child-Pugh and MELD scores evaluated at baseline and after 6 months.

Results

Totally, 60 patients completed the present study (30 patients in the intervention group, and 30 patients in the control group). Hematological and biochemical parameters were normal in both groups with no significant differences at baseline and 6 months after intervention values. Moreover, the renal function indicators including serum creatinine (Cr) and urea (BUN) decreased significantly after intervention. Hepatic parameters also decreased significantly 6 months after intervention. Decreases in the renal and hepatic parameters 6 months after baseline in the control group were not statistically significant.

Conclusion

The results of this study showed that NAC improved hepatic and renal function by decreasing serum urea and creatinine levels but had no significant effect on hematological and biochemical parameters. Furthermore, NAC significantly improved hepatic profiles by decreasing ALT, AST, and ALP in the liver enzymes between the intervention and control groups. Moreover, NAC caused a significant decrease in Child-Pugh and MELD scores.

The pathogenesis of renal injury in obstructive jaundice: A review of underlying mechanisms, inducible agents and therapeutic strategies

Kidney injury is one of the main complications of obstructive jaundice (OJ) and its pathogenesis has not been clarified. As an independent risk factor for OJ associated with significant morbidity and mortality, it can be mainly divided into two types of morphological injury and functional injury. We called these dysfunctions caused by OJ-induced kidney injury as OJKI. However, the etiology of OJKI is still not fully clear, and research studies on how OJKI becomes a facilitated factor of OJ are limited. This article reviews the underlying pathological mechanism from five aspects, including metabolisms of bile acids, hemodynamic disturbances, oxidative stress, inflammation and the organic transporter system. Some nephrotoxic drugs and measures that can enhance or reduce the renal function with potential intervention in perioperative periods to alleviate the incidence of OJKI were also described. Furthermore, a more in-depth study on the pathogenesis of OJKI from multiple aspects for exploring more targeted treatment measures were further put forward, which may provide new methods for the prevention and treatment of clinical OJKI and improve the prognosis.

Safety and efficacy of adding intravenous N-acetylcysteine to parenteral L-alanyl-L-glutamine in hospitalized patients undergoing surgery of the colon: a randomized controlled trial

BACKGROUND

Colon surgery can cause systemic inflammatory response syndrome (SIRS). There is a recent trend towards the use of antioxidant agents in the prevention or alleviation of the severity of postoperative SIRS, but its use is controversial as studies have shown conflicting results.

OBJECTIVES

Investigate the efficacy and tolerability of perioperative intravenous administration of N-acetylcysteine (NAC) as an antioxidant and anti-inflammatory agent in patients undergoing colon surgery.

DESIGN

Randomized, double-blinded, and controlled clinical trial.

SETTING

Surgical critical care unit in Egypt.

PATIENTS AND METHODS

Sixty patients who required admission to the ICU following colon surgery were enrolled in the study between July 2015 and October 2016. Eligibility included the need for parenteral nutrition for at least 5 days due to failure of or contraindication to enteral nutrition. Patients were randomly allocated using a computer-generated list to a loading dose of NAC followed by continuous infusion started one hour prior to induction, and continued over 48 hours, or to the control group, who received the same volume of dextrose 5%. Allocation was concealed using opaque, sealed envelopes under pharmacy control. The researcher, the anesthesiologist, the surgeon, and patients were blinded to the treatment allocation.

MAIN OUTCOME MEASURES

Clinical and laboratory evaluation for manifestations of SIRS, serum levels of tumor necrosis factor alpha and malondialdehyde, and occurrence of side effects in the study group.

SAMPLE SIZE

60 patients with mean (SD) ages of 56 (15.1) years in the study group (n=30) and 57.7 (12.3) years in the control group (n=30).

RESULTS

There was a significant difference in the mean serum level of ALT (22.6 (9.9) U/L in the study group vs. 31.1 (17.8) U/L in the control group, P=.028) after treatment with NAC, but differences between the groups in the serum level of tumor necrosis factor alpha and malondialdehyde after treatment were not significant. Serum levels of malondialdehyde increased in both groups after treatment P<.001. There was no statistically significant difference from baseline or between the groups after treatment in other clinical data and laboratory parameters following NAC administration, and only 6.6% of the patients in the study group experienced mild side effects.

CONCLUSIONS

Preoperative administration of NAC is safe, but its efficacy as an antioxidant and anti-inflammatory agent was not statistically significant and requires further investigation in a larger sample.

LIMITATIONS

Single-center study, small sample size, and short duration of NAC administration.

CLINICAL TRIALS REGISTRY

NCT03589495.

CONFLICT OF INTEREST

None.