Folic acid deficiency in intensive care patients: comparison between two regimens of supplementation.

Serum folic acid (SFA) and red blood cell folic acid (RbcFA) levels were determined in 40 patients on the day of admission to our intensive care unit (ICU, D0). 65% of the patients had low SFA (< 3,4 ng/ml) and 27.5% had low RbcFA (< 275 ng/ml)L. Twenty-four hours later (Day 1:D1), both SFA and RbcFA had decreased significantly (respectively 0.49 ng/ml and 21 ng/ml, p < 0.01) in the 40 patients; the magnitude of RbcFA decrease was greater in patients with sepsis than in those without sepsis (p < 0.02). SFA and RbcFA levels were significantly lower in patients with sepsis on D0 and D1. Forty-two other patients with documented hypofolatemia were then randomly allocated to two regimens of FA supplementation. Patients on regimen A had an intravenous injection of 0.5 mg folinic acid daily for ten days whereas patients on regimen B received a single 5 mg intravenous injection of FA on day 1. Both regimens increased significantly SFA and RbcFA levels. But regimen A should be recommended because 1) RbcFA levels were significantly higher than with regimen B (p < 0.05) and 2) the mean increase was higher, particularly in patients with initial sepsis (p < 0.01).

Ultrasensitive assay of thyroid stimulating hormone in patients with acute non-thyroidal illness.

Serum TSH in critically ill euthyroid patients is generally within the normal range when measured with conventional radioimmunoassays. Sensitive immunoradiometric assays allow detection of low levels of serum TSH. We assessed this method in a prospective study of 34 euthyroid patients admitted to our critical care unit. Serum TSH ranged from 0.12 to 3.60 mU/l and was significantly lower for the whole group than in the controls (P less than 0.001), as also were serum total T4 and T3 values (P less than 0.001). However, 21 patients had a serum TSH within the normal range (group 1) and 13 patients (33%) had a serum TSH less than 0.40 mU/l (group 2). The two groups did not differ in age, sex, type and severity of illness, outcome, and serum T4 and T3 levels. However, the magnitude of TSH increase from the baseline value after the i.v. injection of 200 micrograms of TRH, assessed by the 30 min TSH/basal TSH ratio was significantly higher in group 2 (P less than 0.05). These results suggest that a substantial proportion of patients with acute illness have a clearly low serum TSH, unaccounted for by age, sex, type or quantified severity of illness, serum T4 and T3 levels. In addition, the secretory capacity of the pituitary to exogeneous TRH is significantly enhanced in those patients with low basal TSH.

Current concepts in immune derangement due to undernutrition.

Protein-calorie malnutrition (PCM) adversely affects more or less all immune competent cells. Nonspecific immunity is impaired, particularly adherence and chemotaxis of phagocytes, although the responsiveness of circulating cells may not be the same as that of noncirculating cells. PCM results in numerical and functional impairment in lymphocytes. PCM markedly affects IgG class antibodies which have the highest affinity when directed against T-dependent antigens. These impairments are interrelated, since cooperation between T-helper cell and B-cells is depressed, and the antigen presentation to T-helper cells by macrophages is deficient.

Simple assessment of the nutritional status in the critically ill patient.

The assessment of nutritional status in intensive care patients can be easily accomplished. The first step is to record the patient's complete medical and social history, and to perform a thorough clinical examination in search of signs of nutritional depletion. Several tests, simple and unexpensive, are available to assess the different compartments of the body such as: anthropometric measurements, weight, skinfold thickness and arm muscle circumference and area; biochemical assays, 24-h urinary excretion of creatinine and 3 methylhistidine, serum albumin, transferrin, thyroxin binding prealbumin (TBPA) and retinol binding protein (RBP). The authors report their own data, collected in 150 patients. Nearly all the patients' values are significantly lower than those of the controls; CHI, serum proteins and energy are related to the prognosis; most variables show significant interrelationship: TBPA and RBP are the most frequently decreased values.

Nutritional status in intensive care patients: evaluation in 84 unselected patients.

A prospective nutritional evaluation of 84 unselected patients admitted to a multidisciplinary ICU was performed using anthropometric measurements, creatinine height index (CHI), and serum protein assays. All values tested were significantly lower than those of 40 healthy controls. A matrix of correlation coefficients showed many similarities among the variables studied. Fatal outcome and poor prognosis indices, such as sepsis and renal failure, were analyzed separately. Anthropometric measurements and CHI were not different in the separate groups. Albumin (Alb) and transferrin (Tr) were not different in patients with or without sepsis. Retinol binding prealbumin was significantly higher in patients with renal failure. Thyroxin-binding prealbumin (TBPA) was significantly lower in all the groups. We emphasize the interest of this rapid turnover protein in evaluating nutritional status. We suggest: (1) a systematic nutritional assessment, and (2) an aggressive nutritional support in the ICU patient.

Folic acid deficiency and neutrophil dysfunction.

Polymorphonuclear leukocyte functions were studied in 92 patients with protein-calorie malnutrition. Serum folic acid levels were higher than 3 ng/ml in 38 patients and 3 ng/ml or less in 54 patients. Significant differences were found between these two groups of patients with regard to phagocytosis (81.5 +/- 1.9 versus 69.2 +/- 2.0 percent, p less than 0.001) and bactericidal ability (90.6 +/- 1.1 versus 84.5 +/- 2.3 percent, p less than 0.05). Correction of folic acid deficiency in 22 patients was associated with recovery of normal phagocytosis (p less than 0.001) but not bactericidal function. Adding folic acid to the serum of eight patients also restored normal phagocytic function (p less than 0.001). A correlation was found in vivo and in vitro between changes over time in folic acid levels and in phagocytosis.