Screening For Hypoglycemia Research Articles

Hypoglycemia in the newborn

Hypoglycemia in a neonate has been defined as blood sugar value below 40mg/dL. Hypoglycemia is encountered in a variety of neonatal conditions including prematurity, growth retardation and maternal diabetes. Screening for hypoglycemia in certain high-risk situations is recommended. Supervised breast-feeding may be an initial treatment option in asymptomatic hypoglycemia. However, symptomatic hypoglycemia should always be treated with a continuous infusion of parenteral dextrose. Neonates needing dextrose infusion rates above 12 mg/Kg/min should be investigated for the cause of hypoglycemia. Hypoglycemia has been linked to poor neuro-developmental outcome, and hence aggressive screening and treatment is recommended.

Screening for hypoglycemia at the bedside in the neonatal intensive care unit (NICU) with the Abbott PCx glucose meter.

BackgroundPoint of care (POC) glucose meters are routinely used as a screening tool for hypoglycemia in a neonatal setting. Glucose meters however, lack the same accuracy as laboratory instruments for glucose measurement. In this study we investigated potential reasons for this inaccuracy and established a cut off value for confirmatory testing.MethodsIn this prospective study, all patients in the neonatal intensive care unit who had a plasma glucose test ordered were eligible to participate. Demographic information, sample collection information (nine variables) and a recent hematocrit value were recorded for each sample. Glucose measurements were taken at the bedside on the glucose meter (RN PCx) as well as in the laboratory on both the glucose meter (LAB PCx) and the laboratory analyzer (PG). Data were analyzed by simple and mixed-effects regression analysis and by analysis of a receiver operator characteristics (ROC) curve.ResultsThere were 475 samples analyzed from 132 patients. RN PCx values were higher than PG values (mean = 4.9%), while LAB PCx results were lower (mean = -5.2%) than PG values. Only 31% of the difference between RN PCx – PG and 46% of the difference for LAB PCx – PG could be accounted for by the variables tested. The largest proportion of variance between PCx and PG measurements was explained by hematocrit (about 30%) with a greater effect seen at glucose concentrations ≤4.0 mmol/L (≤72 mg/dL)(48% and 40% for RN PCx and LAB PCx, respectively). The ROC analysis showed that for detection of all cases of hypoglycemia (PG < 2.6 mmol/L)(PG < 47 mg/dL) the PCx screening cut off value would need to be set at 3.8 mmol/L (68 mg/dL) requiring 20% of all samples to have confirmatory analysis by the laboratory method.ConclusionThe large difference between glucose results obtained by PCx glucose meter compared to the laboratory analyzer can be explained in part by hematocrit and low glucose concentration. These results emphasize that the glucose meter is useful only as a screening device for neonatal hypoglycemia and that a screening cut off value must be established.

Screening for hypoglycemia in healthy term neonates: effects on breastfeeding

Transient hypoglycemia in the early neonatal period is a common adaptive phenomenon as the newborn changes from the fetal state of continuous transplacental glucose consumption to intermittent nutrient supply following cessation of maternal nutrition at birth. Research has demonstrated that in the term, healthy newborn, this dynamic process is self-limiting and is not considered pathologic. The American Academy of Pediatrics and the World Health Organization recommend that neonatal blood glucose screening be reserved for newborns who are at risk or symptomatic and conclude that universal hypoglycemia screening is inappropriate, unnecessary, and potentially harmful. Nevertheless, many hospital nurseries continue the clinical practice of routine early glucose screening on healthy, term newborns. This results in the misidentification of neonates captured while experiencing the normal, self-correcting physiologic blood glucose nadir who are then diagnosed with pathologic neonatal hypoglycemia. Subsequent to this misdiagnosis, further surveillance and unnecessary, aggressive treatment interventions will follow that are potentially harmful to the successful establishment of positive maternal-infant interactions and the breastfeeding experience. Research studies indicate that routine hypoglycemia screens, treatments, and interventions in the healthy infant are not evidence-based and result in a serious disruption of the initiation process and duration patterns of lactation. Using the perspective of the theory of technology dependency, this inquiry explores the potential adverse sequelae of inappropriate glucose screening in the healthy breastfeeding newborn and describes selected outcome variables including: 1) the consequences of early maternal-infant separation, 2) the influence of early formula supplementation on breastfeeding discontinuance rates, 3) the effect of separation and supplementation on the onset of lactogenesis, and 4) the impact of hospital staff and provider recommendations of formula supplementation on maternal confidence to independently nurture her baby.

Audit of diabetes care by caseload

OBJECTIVETo investigate the relationship between clinic provision, consultant and nursing caseload, and processes and outcomes of diabetes care in children.DESIGNRetrospective audit in the South Western region of England of 801...

Detecting Hypoglycemia in Venous Blood: Comparison of Two Neonatal Bedside Glucose Monitors

We evaluated the performance of the One Touch II Hospital in neonatal mode (Lifescan, Militipas, Calif) and Accu-Chek II (Boehringer Mannheim, Indianapolis) in screening for neonatal hypoglycemia. We used blood with low-to-normal glucose concentrations and a wide range of hematocrits to mimic infant blood. Single-donor adult blood was collected in heparinized tubes and allowed to metabolize overnight. Red blood cells were separated and reconstituted with the plasma, normal saline, and 10% dextrose to 5 hematocrits and 6 approximate plasma glucose concentrations. All 30 combinations of hematocrit and glucose concentration were tested. The One Touch II Hospital glucose monitor showed the best accuracy of numeric results (32%–78% vs ll%–54%), precision (pooled standard deviation, 1.4 mg/dL vs 4.6–13.9 mg/dL), and correlation (Pearson’s r, 0.95–0.98 vs 0.82–0.86). Sensitivity and specificity for hypoglycemic glucose levels were statistically similar.

Hypoglycaemia caused by atypical insulin antibodies in a patient with benign monoclonal gammopathy

We describe a 48-year-old woman with recurrent severe hypoglycaemia apparently caused by a paraprotein with insulin-binding capacity. Very high fasting values were found for serum insulin (170 and > 250 mU l-1) as well as for proinsulin 125 pmol l-1 and an insulinoma was suspected. Hypoglycaemia developed after an oral glucose tolerance (OGTT) test but not during fasting for 48 h. Free insulin and C-peptide were normal during OGTT whereas serum insulin was very high. 125I-insulin binding to serum, determined with a polyethylene glycol (PEG) precipitation method was high (40%), and equally high after addition of 1.7 x 10(-5) mol l-1 cold insulin to estimate non-specific binding. By adding very high concentrations of cold insulin, displacement of 125I-insulin bound to serum was found (50% displacement at 4 x 10(-5) mol l-1). No immunoglobulin G (IgG) insulin antibodies were detected by radioimmunoelectrophoresis. On agarose electrophoresis a small paraprotein (4 g l-1) in the gamma-globulin fraction was detected. 125I-insulin binding to this paraprotein was demonstrated. We conclude that if insulin autoantibodies are suspected as a cause of hypoglycaemia screening for insulin antibodies should always be done with a PEG-precipitation method.

The Frequency of Hypoglycemia in Full-Term Large and Small for Gestational Age Newborns

Although various authors recommend screening for hypoglycemia in large for gestational age (LGA) and small for gestational age (SGA) newborns, the frequency of hypoglycemia in these infants, using a recent definition of hypoglycemia, and the proper duration of screening are not documented. We determined chromogen test strip blood glucose values at ages 1, 2, 3, 6, 12, 24, 36, and 48 hours in full-term LGA and SGA infants whose mothers were not diabetic. Serum glucose determination was immediately done if a test strip reading was less than 40 mg/dl. Hypoglycemia was defined as a serum glucose less than 35 mg/dl at less than 3 hours of age, less than 40 mg/dl at 3 to 24 hours of age, and less than 45 mg/dl at more than 24 hours of age. The frequency of hypoglycemia in LGA infants was 8.1% (95% confidence interval [CI] 5.0 to 11.2%), and in SGA infants, 14.7% (95% CI 9.8 to 19.6%). The mean age at which hypoglycemia occurred was 2.9 hours (range, 0.8 to 8.5) in LGA infants, and 6.1 hours (range, 0.8 to 34.2) in SGA infants. There were no differences in other possible risk factors between the hypoglycemic and euglycemic infants except that in SGA infants meconium-stained amniotic fluid (40% vs 20%, p = .001), maternal preeclampsia (27% vs 8%, p = 0.0056), and male sex (29% vs 9%, p = 0.029) were more common in hypoglycemic than in euglycemic infants. These data suggest that screening for hypoglycemia in LGA infants whose mothers are not diabetic may be stopped after 12 hours, but should continue for 48 hours in SGA infants.

The Iowa hospital visitation program: does outreach education affect management of neonatal resuscitation?

Thirty-nine Iowa hospitals were visited by a perinatal education team to improve management of neonatal resuscitation. Patient care was evaluated by reviewing medical records according to pre-established performance standards. Following patient-care review, educational programs were offered to physicians and nurses. The hospitals were first visited from July 1982 until June 1984. Follow-up visits were made during the next two years. Management of neonates born in meconium was initially inadequate, but improved during the second period. Similarly, the conduct of other neonatal care practices showed statistically significant improvement over time (including assisted ventilation, hypoglycemia screening, cardiac massage, temperature maintenance, and record documentation). Only treatment of hypoglycemia failed to show significant change. We discuss why a cause and effect relationship cannot be claimed even though the desired effect of the educational intervention was achieved.

The flashlight test lacks validity as a screen for nocturnal hypoglycemia.

Though never validated, the flashlight test is a commonly used screen for nocturnal hypoglycemia. Between 2 a.m. and 4 a.m., we applied the test to 107 children at Eagle's Nest Camp for Children with Diabetes. We validated the test against simultaneously determined capillary blood glucose values (Glucoscan). An eyelid squint in response to the flashlight was considered an intact test. No significant difference existed between mean glucoses for intact and nonintact responses. Both sensitivity and positive predictive value are too low for the flashlight test to be useful in screening for nocturnal hypoglycemia.

Performance evaluation of glucometer R/dextrostix R in the glucose range of interset for screening for neonatal hypoglycemia

Previous reports have shown that heparin is an inhibitor of casein kinase-2 (CK-2). It is unclear whether heparin is also an inhibitor of glycogen synthase (casein) kinase-1 (CK-1), a type 1 casein kinase. In this study it is shown that CK-1 is potently inhibited by heparin when phosvitin or calcineurin are used as substrates. With casein as a substrate, however, the kinase is insensitive to inhibition by heparin. Using phosvitin as a substrate half-maximal inhibition of CK-1 was observed with 0.14 μg/ml heparin. Kinetic analyses indicate that at a constant concentration (0.10 mm) of ATP the Km of CK-1 for phosvitin is increased eightfold in the presence of 0.9 μg/ml heparin; the Vmax is unchanged with or without heparin. At a constant concentration of phosvitin (4 mg/ml) heparin (0.9 μg/ml) decreased the Vmax for ATP by 57%; the Km is unchanged with or without heparin. The inhibition of CK-1 by heparin can be reversed by KCl (>100 mm). These results indicate that heparin is a potent inhibitor not only of CK-2 but also of CK-1. Hence heparin inhibition can no longer be arbitrarily used as a criterion to discriminate between these kinases.

The use of dextrostix and dextrostix reflectance meters in the diagnosis of neonatal hypoglycemia

Dextrostix is now widely used as a method of screening for hypoglycemia of the newborn. There has always been some anxiety about its accuracy for estimating very low blood sugars; this is important, since symptomatic hypoglycemia of the newborn does not usually occur until the blood glucose falls below 20 mg/dl. In 1970 a reflectance meter was introduced which would measure the colour of the strip electronically. The aim of this study was to assess the accuracy of the meter and its reliability in estimating hypoglycemia. The study was continued to investigate a new model of the reflectance meter which superseded the original one. In the pilot study using the original model, blood samples were taken from 46 babies. Readings of the Dextrostix were made by two independent observers and compared with a reading taken on the reflectance meter. These estimations were later compared with blood glucose measured by the glucose oxidase method. the meter showed a marked tendency to overestimate the blood glucose: 44 out of 46 samples were overestimated (Fig. 1, 2). In the second series 180 cord blood samples were collected. Because the intention was to study very low levels of blood glucose, the samples were allowed to stand at room temperature for several hours to allow glycolysis to occur. Again, readings were taken by two independent observers and compared with the readings taken on the new Dextrostix-Eyetone meter. The blood glucose was measured on each of the samples. There was a strong correlation (r = 0.8877, p less than 0.00005) between the blood glucose values and the readings taken from the meter, with no tendency towards overestimation (Fig. 3). A similar correlation (r = 0.8533, p less than 0.00005) was seen for the observers' readings and the chemical method, although there was a tendency to underestimate blood glucose (Fig. 4). When the meter gave an estimate of more than 20 ml/dl, in no case was the actual blood glucose in the profoundly hypoglycemic group of less than 10 mg/dl. When estimated by eye there was one case in which the blood glucose was only 7 mg/dl but the observer had estimated the result of 30 mg/dl. In order to avoid any possibility that a blood glucose was less than 20 mg/dl, it is necessary to take action on any estimate below 40 mg/dl on a Dextrostix. Despite this, Dextrostix remains a very useful method of screening for neonatal hypoglycemia, whether assessed by eye or with the new Dextrostix-Eyetone meter. the meter does give better results than estimating Dextrostix by eye, but the difference was never statistically significant.

Diagnostic value of sodium tolbutamide test in hypoglycemia.

The intravenous Na-tolbutamide test was done on various types of hypoglyce-mia and the following conclusions were obtained: (1) Though very useful in the screening of hypoglycemia, the test is not always satisfactory for the differential diagnosis of various types of hypoglycemia. (2) The diagnosis of hypoglycemia by means of the Na-tolbutamide test is con-sidered practically established when the recovering ability from hypoglycemic levels is absent or insufficient, so as to give a value of the recovery index mostly 0.5 or less, and the stationary value is not higher than 55mg/100ml. (3) Pronounced hypoglycemia occasionally persists in some cases of functional hypoglycemia. Temporary rise in the blood sugar levels is observed in some cases of pancreatic hyperinsulinism. Differential diagnosis between the two types of hypoglycemia is impossible when only the Na-tolbutamide test is employed. (4) In a patient with diabetes complicated with hypoglycemia, the blood sugar level 20 and 30 minutes after intravenous tolbutamide injection showed an obvious decrease in the decline rate. (5) Biphasic fluctuations of blood sugar levels after intravenous tolbutamide injection were observed in three cases of hyperinsulinism.

Hypoglycemia Screening During Sleep

To the Editor:— The central nervous system requires cellular glucose for neurological function. With low blood glucose, cellular level in the CNS falls and neurological response is similarly affected. Measure of this by light response on the retina is of value in insulin-treated diabetics to rule out hypoglycemia during sleep. The problem of hypoglycemic shock during the hours of sleep for those who require exogenous insulin in the management of diabetes mellitus has plagued since the advent of insulin. Signs such as perioral pallor, sweating, restless movements, or unusual vocal activity are not always present. They may represent more than mild hypoglycemia! To awaken an individual to ascertain his status is disturbing, to say the least. Most families seek to avoid this vexing action despite their deep concern. At Camp Seale Harris, full chemical control of the child with diabetes is carefully sought. Many campers have had little chemical control

Advocation of insulin reaction test as the screening for hypoglycemia.

A newly invented insulin sensitivity method was tested in 11 hypoglycemic cases and 80 cases of various other diseases, and recovering ability from hypoglycemia as well as the homeostatic level of blood sugar was determined. In hypoglycemic cases, all of them indicated negative recovering ability and homeostatic values were lower than 63 mg.%. In various other conditions, no case was found which showed both negative recovering ability and lower homeostatic value than 65 mg.%. Other various blood sugar curves were evaluated for the purpose of screening hypoglycemia and it was concluded that only insulin reaction test is recommendable. Author wishes to express his sincere gratitude to Dr. T. Saito, Assistant Professor of Tohoku University Medical School, for his encouragement and various suggestions.