A comparison of prognostic significance of strong ion gap (SIG) with other acid-base markers in the critically ill: a cohort study

BACKGROUND: This cohort study compared the prognostic significance of strong ion gap (SIG) with other acid-base markers in the critically ill. METHODS: The relationships between SIG, lactate, anion gap (AG), anion gap albumin-corrected (AG-corrected), base excess or strong ion difference-effective (SIDe), all obtained within the first hour of intensive care unit (ICU) admission, and the hospital mortality of 6878 patients were analysed. The prognostic significance of each acid-base marker, both alone and in combination with the Admission Mortality Prediction Model (MPM0 III) predicted mortality, were assessed by the area under the receiver operating characteristic curve (AUROC). RESULTS: Of the 6878 patients included in the study, 924 patients (13.4 %) died after ICU admission. Except for plasma chloride concentrations, all acid-base markers were significantly different between the survivors and non-survivors. SIG (with lactate: AUROC 0.631, confidence interval [CI] 0.611-0.652; without lactate: AUROC 0.521, 95 % CI 0.500-0.542) only had a modest ability to predict hospital mortality, and this was no better than using lactate concentration alone (AUROC 0.701, 95 % 0.682-0.721). Adding AG-corrected or SIG to a combination of lactate and MPM0 III predicted risks also did not substantially improve the latter's ability to differentiate between survivors and non-survivors. Arterial lactate concentrations explained about 11 % of the variability in the observed mortality, and it was more important than SIG (0.6 %) and SIDe (0.9 %) in predicting hospital mortality after adjusting for MPM0 III predicted risks. Lactate remained as the strongest predictor for mortality in a sensitivity multivariate analysis, allowing for non-linearity of all acid-base markers. CONCLUSIONS: The prognostic significance of SIG was modest and inferior to arterial lactate concentration for the critically ill. Lactate concentration should always be considered regardless whether physiological, base excess or physical-chemical approach is used to interpret acid-base disturbances in critically ill patients

Mineral nutrition of food legumes in Thailand with particular reference to micronutrients

THE aims of the study were to determine the extent and severity of micronutrient deficiencies for the production of the food legume crops, black gram, green gram, peanut and soybean, in four regions of Thailand (north, northeast, central and southeast), and to develop procedures for their diagnosis, prediction and correction in farmers' crops. The importance of macronutrient deficiencies in legume crop production was also explored and procedures for their diagnosis developed. The study has shown that a high proportion of legume crops in Thailand suffer from one or more deficiencies of the micronutrients boron (B) and molybdenum (Mo) and the macronutrients phosphorus (P), potassium (K), sulfur (S), and nitrogen (N)

Iron deficiency in peanut on black calcareous soils

Black calcareous soils of Thailand (Rendzinas or Calciustolls) occupy 500 000 ha and are located mostly on the highlands of central and northern areas of the country. These soils are considered quite fertile, but leaf chlorosis resembling iron deficiency occurs quite commonly in peanuts, although patchy in distribution

Iron nutrition of field crops in black calcareous soils of Thailand: A review

Iron (Fe) deficiency limits crop production on black calcareous soils (Typic Calciustolls) of Thailand with reports of Fe deficiency becoming more common. Much of the Fe in these soils occurs as free crystalline and amorphous Fe oxides and DTPA extractable Fe is low averaging 6. 4 mg/kg in 20 soils examined. Field studies showed that Fe deficiency could be alleviated by soil amendments such as elemental sulfur or by soil and foliar Fe fertilizer, provided rates of application were high enough. However, since soil amendment and Fe fertilizer use is costly, preliminary research into cultivar selection for Fe efficiency has begun with peanuts. Kernel yields in 20 cultivars were inversely related to Fe chlorosis scores. Standards for diagnosis and prediction of Fe deficiency in field crops are being developed for soil and plant analyses using DTPA and o‐phenanthroline, respectively

On-farm trials for molybdenum requirement of groundnut

Previous survey of Mo concentrations in young fully expanded leaves (YFEL) of farmers' groundnut crop in many areas of the Northeast and East Thailand revealed that many samples contain rather low Mo concentration, indicating that those areas may be deficient in Mo for groundnut. In 1988, field trails were conducted at 3 of the low Mo locations in the Northeast. Groundnut cultivar Tainan 9 were treated with 2 rates of Mo (0 and 500 g. Mo/ha) and supplied with complete fertilizers, i.e., P, K, Mg, S, Cu, Zn and B, at planting; supplementary gypsum was supplied at pegging. At flowering, adding Mo greatly increased shoot dry matter, N content and N concentration in YFEL and also increased Mo concentration in nodules, tops and YFEL. Molybdenum application increased seed yield of groundnut at Ban Had by 19 % but not at the remaining two sites, despite the fact that all had low levels of extractable Mo in the soils. These soils release sufficient Mo from adsorbed forms to satisfy the requirement of groundnut cultivar Tainan 9 for seed dry matter yiel