Perioperative changes in alpha 1-acid glycoprotein concentrations in infants undergoing major surgery

Abstract

alpha 1-Acid glycoprotein (AAG) is an acute phase protein that is responsible for binding basic drugs such as bupivacaine. In order to determine how AAG concentrations change in response to surgical stress, arterial blood samples were obtained from 50 infants undergoing major surgery, at induction of anaesthesia and daily for the next 7 days. AAG concentrations were measured using a rate nephelometric technique. The overall mean preoperative AAG concentration was 0.38 (SD 0.16) mg ml-1, although concentrations were significantly greater in infants undergoing urgent surgery compared with those undergoing elective surgery (P = 0.02). There were no significant correlations between gestational or postnatal age and preoperative AAG concentration. Mean AAG concentrations increased to 0.76 (0.18) mg ml-1 by day 4 after surgery and stayed at that concentration thereafter. Infants with preoperative AAG concentrations < 0.38 mg ml-1 showed a greater percentage increase in postoperative AAG concentrations than did infants with preoperative AAG concentrations > 0.38 mg ml-1 (P = 0.001). We conclude that preoperative measurement of AAG may identify those infants most at risk of drug toxicity in the early postoperative period.

High-performance liquid chromatography determination of α1-acid glycoprotein in small volumes of plasma from neonates

“…The AGP plasma concentrations of patients receiving continuous infusions showed significant increases with time. The results were similar to those reported previously [18], which showed an increase in mean AGP concentration from 38 mg/100 ml (preoperative; range 7-78 mg/100 ml) to 76 mg/100 ml by day 4. Similar results were found by Larsson et al [19], while investigating AGP levels in neonates after continuous epidural infusion.…”

“…HPLC has become widely used for the quantitative analysis of proteins in recent years. Although AGP has been measured in urine by direct injection onto a reversed-phase HPLC column [15,16], the analysis of AGP in plasma by HPLC, as described by [17] and [18], is relatively complex. The latter method applied a solvent extraction followed by microanalytical ion-exchange chromatography for measuring AGP in human serum.…”

Population clinical pharmacology of children: modelling covariate effects

“…"Baby fat" is lost when the infant starts walking and protein mass increases (20% term neonate, 50% adult). Albumin, globulin, lipoprotein and glycoprotein concentrations change over the first year, affecting drug binding [16]. Relative body proportions change dramatically over the first few years of life and may affect the volumes of the distribution of drugs.…”

Role of TNF-α in Local Surgical Trauma-Induced Microvascular Dysfunction

“…Systemic host response after major traumatic injury can be quantified by several definitive parameters, including hormonal change, cellular differentiation, as well as acute phase protein synthesis, and cytokine production [8, 9, 10, 11], whereas local response after traumatic/surgical injury has been assessed mostly by indirect methods, e.g. thermography and laser Doppler flowmetry, or just by the appearance of wound healing.…”