[Preoperative nutritional status and surgical risk. Identification of promissory biochemical markers]. / Estado nutricional preoperatorio y riesgo quirúrgico. Identificación de marcadores bioquímicos promisorios.

BACKGROUND: The fact that deficient or even marginal nutritional levels may contribute to increase morbidity and mortality in the surgical patient is well accepted. The usefulness of vitamin and mineral markers has not been much explored. OBJECTIVE: To evaluate the usefulness of vitamin and mineral indicators as nutritional markers of surgical risk. METHODS: Biomarkers of vitamin A (plasma retinol), carotenes (plasma carotenes), vitamin C (plasma vitamin C), iron (hematocrit, hemoglobin, serum iron, transferrin saturation and erythrocyte protoporphyrin), calcium (calcium/creatinine in basal urine) and zinc (zinc/creatinine in basal urine), were performed 24 ours before surgery. Appearance of complications was evaluated in 100 adult patients from programmed surgical procedures of hernia (n = 41) or gallbladder lithiasis (n = 59), two of the most frequent interventions in general surgery services. RESULTS: Patients were grouped in those that presented postoperative complications (C; n = 26) and those who did not (NC; n=74). Two of the studied markers presented significant differences between both groups: plasma retinol and erythrocyte protoporphyrin. Plasma retinol of C was significantly lower than that obtained in NC: 33.2 +/- 13.5 microg/dl vs. 40.2 +/- 16.3 microg/dl; P = 0.0495 and an association between values below 30 microg/dl and postoperative complications was founded (53.8% in C vs. 30.1% in NC; P = 0.0360). Erythrocyte protoporphyrin of C was significantly higher to that obtained in NC: 52.0 +/- 34.0 microg/dl RBC vs. 36.8 +/- 17.5 microg/dl RBC; P = 0.0453 and the association between values higher than 70 microg/dl RBC and presence of complications were highly significant (25.0% vs. 4.2%; P = 0.0069). CONCLUSIONS: On the basis of the obtained results is concluded that plasma retinol and erythrocyte protoporphyrin would provide useful tools in evaluating surgical risk since they had been allowed to identify patients who were at risk of suffering postoperative complications.

Estado nutricional preoperatorio y riesgo quirúrgico. Identificación de marcadores bioquímicos promisorios / Preoperative nutritional status and surgical risk. Identification of promissory biochemical markers

Introducción: Existe una acumulación de evidencias de que niveles de nutrición deficientes o aún marginales pueden contribuir al aumento de morbilidad y mortalidad en el paciente quirúrgico. La utilidad de marcadores de vitaminas y minerales ha sido poco explorada. Objetivo: Evaluar la utilidad de indicadores de vitaminas y minerales como marcadores de riesgo quirúrgico. Métodos: Se estudió la asociación entre marcadores de vitamina A (retinol plasmático), carotenos (carotenos plasmáticos), vitamina C (vitamina C plasmática), hierro (hematocrito, hemoglobina, hierro sérico, saturación de transferrina y protoporfirina eritrocitaria), calcio (calcio/creatinina en orina basal) y zinc (zinc/creatinina en orina basal), realizados dentro de las 24 horas previas a la cirugía, y la aparición de complicaciones postoperatorias en 100 pacientes adultos sometidos a intervenciones por hernia (n = 41) o litiasis vesicular (n = 59), dos intervenciones muy frecuentes en los servicios de cirugía general. Resultados: Los pacientes se dividieron en aquellos que presentaron complicaciones postoperatorias (C; n = 26) y aquellos que evolucionaron sin complicaciones (NC; n = 74). Dos de los marcadores estudiados fueron los que presentaron las mayores diferencias entre ambos grupos: retinol plasmático y protoporfirina eritrocitaria. El retinol plasmático del grupo C fue significativamente menor al del grupo NC: 33,2 ± 13,5 μg/dl vs 40,2 ± 16,3 μg/dl; P = 0,0495 y se halló asociación significativa entre valores inferiores a 30 μg/dl y aparición de complicaciones (53,8% en C vs 30,1% en NC; P = 0,0360). La protoporfirina eritrocitaria del grupo C fue significativamente mayor a la del grupo NC: 52,0 ± 34,0 vs 36,8 ± 17,5 μg/dl g.r; P = 0,0453 y la asociación entre valores superiores a 70 μg/dl g.r. y presencia de complicaciones fue altamente significativa (25,0% vs 4,2%; P = 0,0069). Conclusiones: Dos indicadores de micronutrientes: retinol plasmático y protoporfirina eritrocitaria, resultaron marcadores promisorios de riesgo quirúrgico por haber permitido identificar pacientes en riesgo de sufrir complicaciones postoperatorias (AU)

Background: The fact that deficient or even marginal nutritional levels may contribute to increase morbidity and mortality in the surgical patient is well accepted. The usefulness of vitamin and mineral markers has not been much explored. Objective: To evaluate the usefulness of vitamin and mineral indicators as nutritional markers of surgical risk. Methods: Biomarkers of vitamin A (plasma retinol), carotenes (plasma carotenes), vitamin C (plasma vitamin C), iron (hematocrit, hemoglobin, serum iron, transferrin saturation and erythrocyte protoporphyrin), calcium (calcium/creatinine in basal urine) and zinc (zinc/creatinine in basal urine), were performed 24 ours before surgery. Appearance of complications was evaluated in 100 adult patients from programmed surgical procedures of hernia (n = 41) or gallbladder lithiasis (n = 59), two of the most frequent interventions in general surgery services. Results: Patients were grouped in those that presented postoperative complications (C; n = 26) and those who did not (NC; n=74). Two of the studied markers presented significant differences between both groups: plasma retinol and erythrocyte protoporphyrin. Plasma retinol of C was significantly lower than that obtained in NC: 33.2 ± 13.5 μg/dl vs. 40.2 ± 16.3 μg/dl; P = 0.0495 and an association between values below 30 μg/dl and postoperative complications was founded (53.8% in C vs. 30.1% in NC; P = 0.0360). Erythrocyte protoporphyrin of C was significantly higher to that obtained in NC: 52.0 ± 34.0 μg/dl RBC vs. 36.8 ± 17.5 μg/dl RBC; P = 0.0453 and the association between values higher than 70 μg/dl RBC and presence of complications were highly significant (25.0% vs. 4.2%; P = 0.0069). Conclusions: On the basis of the obtained results is concluded that plasma retinol and erythrocyte protoporphyrin would provide useful tools in evaluating surgical risk since they had been allowed to identify patients who were at risk of suffering postoperative complications (AU)

[Nutritional status of surgical patients without apparent nutritional compromise]. / Estado nutricional de pacientes quirúrgicos sin aparente compromiso nutricional.

Nutritional status of 80 preoperative patients from programmed surgeries of hernias and lithiasis was studied by anthropometric and biochemical parameters. Nutritional deficiencies related to pathology were not expected in these patients. Results were as follows: 77% of the population showed overweight, being 15% obese. Prevalent protein intake, evaluated by the urea nitrogen/creatinine ratio, was adequate in 87.5% of the patients; however, patients presented 72% of albumin, 52% of prealbumin and 50% of RBP below reference values. Transferrin, ceruloplasmin, alpha 2-macroglobulin and haptoglobin were not decreased. Assessment of vitamin A, carotenes and vitamin C showed plasmatic levels below reference values in 16% of the patients for vitamin A, 5% for carotenes and 27% for vitamin C. Respect to calcium status, data of calcium/creatinine ratio show deficiency in 45% of the population. Respect to iron, the nutritional status was in general adequate, patients at risk being 5% by Htc, 11% by Hb, 5% by TS% and 12.5% by FEP, women showed over twice abnormal values than men. Although some isolated relations were observed, in this population sex, age and pathology were variable that did not affect in a relevant way the nutritional status. In spite of the individual analysis of each nutrient did not show important deficiencies, the analysis by patient showed that only a few of them (7%) presented an optimal biochemical profile with all the studied parameters within the reference values.