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PubMedDate not supplied

Variations in lactate apparent clearance during rest and exercise in normal man.

The purpose of this study is to present a simple kinetic model for the study of the lactate metabolism. This model based on pharmacokinetic theory, does not require labelled molecules and yields a finer approach to lactate metabolism than does a simple observation of blood lactate concentration. The variations in parameter values have been studied in six male subjects after intensive exercise (385 W, 110 rpm and 1 min) (IE) followed by three different recovery periods: passive recovery (RE), moderate exercise (ME) and heavy exercise (HE). Blood lactate concentration was measured prior to IE and during the first hour of recovery. After mathematical treatment, the results show that the apparent clearance increases 2.83 +/- 0.76 fold from RE to ME and 1.96 +/- 0.61 fold from RE to HE. The steady state blood lactate concentration induced by the intensity of recovery (La(ss)) increases slightly (1.53 +/- 0.37 fold) from RE (1.40 +/- 0.36 mmol.l-1) to ME (2.04 +/- 0.32 mmol.l-1). Then La(ss) increases markedly (3.78 +/- 0.91 mmol.l-1) during HE (2.81 +/- 0.78 fold the La(ss) value at RE). The ratio between the apparent rates of lactate production (F"K0) during RE, ME and HE was calculated. F"K0 increases in a linear way versus intensity of exercise recovery. It was concluded that in the human: 1) the blood lactate concentration is not an accurate indicator of lactate production, 2) in our experiment, the apparent lactate production is a linear function of exercise intensity and 3) the abruptly increasing blood lactate concentration at a high level of exercise intensity is due to a decrease in apparent clearance.

Adult↗
PubMed2004

Genotype and diet effects on energy balance in the first three lactations of dairy cows.

Dairy cows make strategic use of body energy to support early lactation and replenish this lost energy later in lactation, thereby creating body energy profiles that vary both within lactation and across lactations. The interaction between genotype and diet energy content is interesting from a management viewpoint and from a cow survival viewpoint. In this study, we modeled energy balance over 3 lactations using a multivariate random regression model, for cows from the Langhill Dairy Cattle Research Centre. This herd has been selected for maximum production or to remain at the UK national average for production (control group) and has been fed 2 diets of different energy density (high or low concentrate). Cows in the various groups differed in body condition score and the way they lost and regained body lipid. Cows selected for maximum production on a low-concentrate diet lost the greatest amount of body lipid (0.54 condition score units) after 3 lactations. Cows selected for maximum production lost more than control cows on either diet, indicating that selection mainly for yield has predisposed cows to utilize body energy to support lactation on diets spanning the range used here. Cows selected for maximum production were heavier at first calving than control cows but lost more weight and regained more weight so that at the end of each lactation, cows in the 2 groups did not differ significantly in weight. Cows use body lipid to support lactation over 3 lactations and the profile of that use varies according to genotype and diet.

Animals↗
PubMed1983

Age and previous lactations as factors in the amount of bovine colostral immunoglobulins.

Blood and colostrum samples were obtained from 87 dairy cows in five lactation groups and analyzed for immunoglobulins G1, G2, M, and A. The five groups ranged from cows in first lactation, about 30 mo of age, to cows in fifth or more lactation, about 84 mo of age. Compared to older groups, blood serum of cows in first lactation contained less G1. Cows in first lactation also produced less total colostrum containing less total G1, G2, and M. Immunoglobulin G1 comprised over two-thirds of the immunoglobulins in the colostrum of all groups. Older cows had more immunoglobulin G1 in their colostrum with a tendency toward a higher ratio of G1 to G2. Amount of immunoglobulin A was constant through all lactations. After a rise in the second lactation, total amount of immunoglobulins G2 and M tended to level off. Total immunoglobulin G1 tended to reach a maximum in the third or fourth lactation, almost doubling in amount compared to the first lactation. Age and number of lactations are factors correlated with amounts of these immunoglobulins in colostrum.

Age Factors↗
PubMed1993

Effects of recombinant bovine somatotropin (sometribove) on ovarian function in lactating and nonlactating dairy cows.

Metabolic and ovarian responses of lactating and nonlactating cows to recombinant bST (sometribove) were measured. Eighteen lactating cows (60 to 100 d postpartum) and 6 nonlactating cows (> 400 d postpartum) were injected daily with bST or saline during one of two periods. Concentrations of hormones and metabolites were measured in plasma, and ultrasonography was used to quantify ovarian follicular growth. Concentrations of glucose, insulin, IGF-I, progesterone, and estradiol in plasma were greater in nonlactating cows than in lactating cows. Lactating cows had fewer class 2 (6- to 9-mm) and class 3 (10- to 15-mm) follicles and more class 4 (> 15-mm) follicles than nonlactating cows. Bovine somatotropin increased the numbers of follicles in lactating cows so that the numbers of class 2 and of class 3 follicles were equivalent to those for non-lactating cows. Sizes of the largest follicles were similar for bST-and saline-treated cows. The second largest ovarian follicles, however, were larger in bST-treated cows. Ovarian follicular dynamics were altered by bST and lactation. Bovine somatotropin increased the numbers of follicles (6 to 15 mm) in lactating cows and size of second largest ovarian follicles in both lactating and nonlactating cows. Lactating cows developed dominant follicles that were larger and less estrogenic than those of nonlactating cows.

Animals↗
PubMed1993

Empirical and theoretical constraints on the evolution of lactation.

For 829 mammalian species, data on age at weaning or age at first solid food were analyzed with respect to body mass, phylogeny, habitat, diet, length of gestation, basal metabolism, and neonatal development. The primary influence on lactation length is female mass, but phylogenetic constraints are important. Thus, lactation can be characterized as short (earless seals and baleen whales), long (marsupials, bats, and primates), or average (remaining eutherians). Among average mammals, lagomorphs have short lactations. Lactation may have different functions, evolutionary constraints, and physiological control depending on whether young first eat solid food near weaning or well before it. First solid food eaten near weaning occurs in polytocous species with altricial young; in this case, lactation has a clear energetic role. In contrast, first solid food well before weaning is common for mammals with single, precocial offspring. For these species, the energetic and nutritional constraints on lactation may be less important than the benefits of maintaining contact between mother and young, such as reduced juvenile mortality and increased opportunities for learning social or foraging patterns. Thus, the age at first solid food relative to the age at weaning may indicate the function of lactation within the reproductive biology of a given mammal. Delayed development and implantation alter the timing of energetic investment during gestation, so too, the age at first solid food may alter or reflect the rate of energetic investment during lactation. Thus, the age at first solid food relative to the age at weaning may indicate the function of lactation within the reproductive biology of a given mammal. Testing these hypotheses will require data from diverse species on the nutritional and energetic value of milk before and after first solid food as well as on the mechanics and consequences of nursing or suckling during the course of lactation.

Age Factors↗
PubMed1999

Genetic parameters for first and second lactation milk yields of Polish black and white cattle with random regression test-day models.

Single- and two-trait random regression models were applied to estimate variance components of test-day records of milk, fat, and protein yields in the first and second lactation of Polish Black and White cattle. The model included fixed herd test-day effect, three covariates to describe lactation curve nested within age-season classes, and random regressions for additive genetic and permanent environmental effects. In two-parity models, each parity was treated as a separate trait. For milk and the two-parity model, heritabilities were in the range of 0.14 to 0.19 throughout first lactation and 0.10 to 0.16 throughout second lactation. For fat, heritabilities were within 0.11 to 0.16 and 0.11 to 0.22 throughout first and second lactations, respectively. For protein in the two-parity model, heritabilities were within 0.10 to 0.15 throughout most of first lactation and within 0.06 to 0.15 throughout the most of second lactation. For milk, genetic correlations between the first and second parities were 0.6 at the beginning of the lactation, rising to 0.9 in the middle, and 0.8 at the end of the lactation. For fat, the corresponding correlations were 0.6, 0.8, and 0.7, respectively, and for protein were 0.6, 0.8, and 0.8, respectively. Heritability estimates for all traits were flatter for the two-parity model. Relatively smooth genetic and permanent environmental variances with the two-parity model indicated that large swings of heritabilities could be artifacts of single-trait random regression models. High correlations between most of test day records across lactations suggested that a repeatability model could be considered as an alternative to a multiple-trait model to analyze multiple parities.

Algorithms↗
PubMed1994

Mechanisms by which dichloroacetate lowers lactic acid levels: the kinetic interrelationships between lactate, pyruvate, alanine, and glucose.

Dichloroacetate (DCA) is gaining use as an alternative to bicarbonate therapy in the treatment of lactic acidosis. To determine the mechanism(s) by which DCA lowers blood lactate levels, we studied its effect on the kinetic interrelationships between pyruvate, lactate, alanine, and glucose in the hindlimb of dogs during hormonal stimulation of pyruvate production (Ra) and its conversion to lactate. Three groups of dogs (n = 6) were infused with 1-13C-pyruvate to measure whole body pyruvate Ra, and pyruvate Ra and utilization (Rd) across the hindlimb during either a 4-hr infusion of saline (controls), or somatostatin, glucagon, and epinephrine (SGE), or SGE plus dichloroacetate (SGE + DCA). Pyruvate Ra was used as an index of rate of glycolysis and Rd as an index of pyruvate oxidation. In the controls, all kinetic parameters were constant during the saline infusion. Hindlimb pyruvate Ra and Rd were almost equal, and lactate release negligible. Compared to controls, SGE administration significantly increased (P < 0.05) wholebody pyruvate Ra (48.5 +/- 6.2 vs 33.6 +/- 2.4 mumol/kg/min) and blood lactate levels (P < 0.05). Hindlimb pyruvate Ra increased by approximately 150%, but Rd remained unchanged resulting in marked increases in lactate and alanine effluxes. Adding DCA to the SGE infusion significantly reduced wholebody pyruvate Ra (P < 0.05) and blood lactate levels (P < 0.01). In the hindlimb, however, there was no decrease in lactate output, despite a 91% increase in pyruvate utilization because pyruvate Ra also increased. These results suggest that during stimulation of rate of glycolysis, DCA lowers lactate levels by reducing the overall availability of pyruvate for lactate synthesis. This is accomplished by suppressing the rate of glycolysis in tissues other than skeletal muscle and stimulating pyruvate oxidation.

Alanine↗
PubMed2000

Breast carcinoma presenting during or shortly after pregnancy and lactation.

CONTEXT: Much has been written about the clinical management and prognosis of breast carcinomas presenting during pregnancy and lactation, yet little is known about the detailed histopathology of these tumors. OBJECTIVE: To determine whether these carcinomas have any specific diagnostic features. DESIGN: A detailed histologic and immunohistochemical study of 14 cases of breast carcinoma presenting during or shortly after pregnancy or lactation was conducted. The findings were compared with a control group of 13 tumors developing in age-matched women with no recent history of pregnancy or lactation. SETTING: The histopathology department of a tertiary referral teaching hospital. RESULTS: Tumors in the pregnancy/lactation group had a significantly higher incidence of cancerization of lobules (79% vs 15%) and of grade III invasive ductal carcinomas (80% vs 33%). Tumors occurring during lactation were either totally or partly mucinous and were MUC2 positive. Tumors occurring during pregnancy, but not during lactation, were mostly estrogen and progesterone receptor negative (4/5 and 5/5, respectively). All tumors occurring during pregnancy and lactation that were tested for c-erbB-2 overexpression were negative, whereas all 4 tumors tested that occurred shortly after delivery or cessation of lactation were positive for c-erbB-2 overexpression. The incidence of axillary lymph node metastasis was high in both the study and control groups, although it was slightly higher in the control group (78% and 90%, respectively). CONCLUSIONS: Although breast carcinomas diagnosed during or shortly after pregnancy and lactation have features in common with those developing in women of similar ages, particularly with respect to a high incidence of lymph node metastasis, the findings of this study suggest that they may also have distinct morphologic and immunohistochemical features of their own. Such features may vary according to whether the patient was pregnant, lactating, or had recently terminated her pregnancy or lactation at the time of surgical excision. Examination of more cases would help confirm these findings.

Adult↗
PubMed1975

Lactation and reproduction.

The authors review the literature on the effect of lactation on fertility in the absence of contraception and on the effects of contraceptive measures on lactation. They examine data from several countries on the intervals between births and on the return of menstruation and ovulation after childbirth, comparing lactating with nonlactating women. They conclude that lactation is an inefficient contraceptive for the individual, but that in populations sustained lactation is associated with reduced fertility. Possible physiological mechanisms causing lactation amenorrhoea are discussed. Though much of the literature on the effect of contraceptives on lactation is inadequate, there is general agreement that the estrogen component of hormonal preparations has an adverse effect on lactation, but that progestins alone do not. Many questions remain. Is this effect seen in established lactation, or only in the puerperal period? Is it a direct pharmacological effect, or are pill-users the mothers least motivated to maintain breast-feeding? Does a close relationship exist between hormones given and lactation performance? The authors comment on some of the technical deficiencies of previous studies in this field and discuss practical possibilities of, and limitations to, obtaining adequate scientific information in the future.

Amenorrhea↗
PubMed2000

Changes in plasma arginine vasopressin concentration during lactation in rats.

BACKGROUND AND PURPOSE: The objectives of the study reported here were to determine whether a change in the plasma arginine vasopressin (AVP) concentration occurred in lactating, compared with non-lactating rats and to examine the involvement of suckling with plasma AVP concentration. METHODS: Experiments were performed on 86 female Wister Imamichi rats, 12 weeks old at parturition, with fast lactation. On day 13 of lactation, AVP concentration and plasma osmotic pressure were measured in lactating and non-lactating rats. RESULTS: Plasma AVP concentration was always higher in rats of the lactating groups than in non-lactating controls (1.06 +/- 0.28 pg/ml), and a conspicuous increase in AVP concentration was seen during the postsuckling period (1.70-0.61 pg/ml before vs. 2.56 +/- 1.31 pg/ml after suckling, P < 0.05). Plasma osmotic pressure in lactating rats with 12 pups (296.6 +/- 5.2 mOsmol/kg x H2O) was lower than that in rats of the removed control groups (306.7 +/- 5.7 mOsmol/kg x H2O). CONCLUSION: On the basis of these results, it appears that "low plasma osmotic pressure-high AVP status" develops in the lactating period, similar to pregnancy, through resetting of the regulatory mechanism of the AVP system. It was concluded that suckling stimulation could release AVP, which could dilute the blood with water resulting in the increase in circulating blood volume.

Animals↗
PubMedDate not supplied

[The behavior of lactogenic and steroid hormones in the blood of Awassi ewes in Syria during lactation].

The concentrations of lactogenic hormones (prolactin--PRL, growth hormone--GH, insulin-like growth factor I--IGF-I) and steroid hormones (progesterone--PG, estradiol--E2) were determined by RIA in the blood plasma of 8 lactating ewes (3 with twins) and compared with that of 3 non-lactating cycling ewes of the same age. All animals live in a flock of 30 Awassi sheep under identical conditions in Syria. The lactation period (192 +/- 25 days) is divided to a suckling period (until day 63) and a hand milking period (2 fold daily) with different levels of milk production (near 2 litres/day in the former, decreasing from 0.8 to 0.1 litre/day in the latter). During the suckling period the concentrations of steroid hormones in the blood plasma are lower, these of lactogenic hormones are higher of lactating than of non-lactating ewes. During the milking period only the concentrations of E2, PRL and IGF-I in the blood plasma of lactating animals are lower than in non-lactating ewes. But, during this time more and more seasonal influences (increasing day length and temperature) overwhelm the influence of lactation on the hormone secretion. Suckling of twins is accompanied with higher levels of E2, PRL and IGF-I in the blood plasma of their mothers than suckling of single lambs. During the lactation period a strong correlation exists between milk yield and the level of GH (r = 0.85) and IGF-I (r = 0.71), a smaller correlations to the level of E2 (r = 0.49) in the blood plasma of the lactating ewes. During the suckling period the milk yield is influenced positively by PRL (r = 0.77) and GH (r = 0.68), but negatively by PG (r = -0.76). During the milking period the milk yield is determined extensively by the level of IGF-I (r = 0.89) in the blood plasma. The concentrations of the analyzed hormones in the blood plasma correlate always positively together.

Animals↗
PubMed1992

Nutritional and lactational regulation of fertility in sows.

Two major conclusions were drawn from early studies on lactating sows. First, gonadotrophin secretion is suppressed during lactation and this constitutes the primary block to ovarian function and lactational oestrus. Second, in addition to the suckling stimulus per se, nutrition and changes in body condition during lactation have critical effects on post-weaning fertility of sows. Considerable progress has been made in defining the mechanisms that mediate the inhibitory effects of lactation on ovarian development. In sows, active secretion of luteinizing hormone (LH) constitutes an important luteotrophic signal throughout pregnancy. LH secretion may therefore increase in the immediate postpartum period in the suckled sow. In the absence of suckling, this high rate of LH secretion can result in the development of highly oestrogenic but often cystic follicles in the immediate postpartum period. Together with data from studies involving treatment with exogenous gonadotrophins or luteinizing-hormone-releasing hormone (LHRH), this indicates that ovarian sensitivity is not compromised during lactation in sows. The inhibitory effects of suckling on LH secretion, typical of established lactation, are imposed during the first 72 h post partum and from this time the inhibitory mechanism is at least partly opioid dependent. In two recently completed studies, however, it has not been possible to block the development of the suckling-induced suppression of LH by treatment with the opiate antagonist, naloxone, suggesting that other inhibitory mechanisms are involved. Differential regulation of LH and follicle-stimulating hormone (FSH) secretion is evident during lactation, probably as a consequence of ovarian inhibitory, inhibin-mediated control of FSH but not of LH secretion. There is still very little direct evidence for the mechanisms by which the metabolic state of lactating sows affect fertility after weaning. Low plasma insulin, glucose and insulin-like growth factor 1 (IGF-1), and high growth hormone (GH) and cortisol concentrations in sows in a catabolic state are all potentially involved. In lactating sows with a reasonable energy balance, the inhibitory neural effects of suckling are probably more potent inhibitors of LH secretion than are the metabolic demands of milk production.

Animals↗
PubMed1992

Effect of manipulation of plasma lactate on integrated EMG during cycling.

This investigation was undertaken to record electromyographic activity of the vastus lateralis muscle during incremental cycling exercise and to determine whether it would be sensitive to altered dynamics of plasma lactate increases seen with intense exercise. Trained cyclists (N = 6) performed two progressive, stepwise exercise tests (23.5 W.min-1) to fatigue on a cycle ergometer at 90 rpm. One of the exercise tests was preceded by arm ergometer exercise in an attempt to elevate the circulating plasma lactate levels prior to starting the criterion exercise test. The starting mean plasma lactate values were 4.59 and 26.69 mmol lactate.-1 for the two exercise sessions. Cardiorespiratory values did not differ significantly between exercise sessions completed in the absence and presence of increased circulating plasma lactate. The no-arm trial (i.e., nonelevated plasma lactate condition) was associated with a plasma lactate inflection point (Tlac) at 72.6% VO2max. Previous arm exercise elevated the lactate such that during the criterion exercise plasma lactate values were decreasing with increasing power output at lower exercise intensities. As exercise intensity increased lactate values also increased beginning at a power output of about 76% VO2 max. Mean per cycle integrated EMG (CIEMG) increased linearly with increased power output in both exercise sessions. The slopes of the EMG-power output curve were not significantly different (P less than 0.05). There were no inflection points in these curves. The absence of an inflection point show that surface EMG does not provide an indication of Tlac.

Adolescent↗
PubMed1985

Lactate transport in rat aorta.

Ouabain (10 mM) and gramicidin (5 micrograms/ml) do not inhibit lactate uptake by rat aortic rings. This supports the interpretation that a Na+ gradient is not involved in lactate transport. Dinitrophenol (25 microM) fails to inhibit lactate uptake, suggesting that oxidative metabolism is not required for lactate uptake. DIDS (4,4'-diisothiocyano-2,2'-stilbenedisulfonate), quercetin, and alpha-cyano-4-hydroxy-cinnamate-agents that have been reported to inhibit lactate transport in other cell types-were ineffective in inhibiting lactate transport in rat aortic rings. Inhibition of lactate uptake by glyceraldehyde is not stereospecific, does not involve inhibition of glucose phosphorylation, and does not appear to involve interaction with membrane sulfhydryls. PCMBS (p-chloromercuribenzenesulfonate) does not markedly inhibit the initial rate of lactate uptake, but diminishes the lactate space at later times. Pyruvate, phenylpyruvate, and thiolactate inhibit lactate uptake, but propionate and glycolate are poor inhibitors.

Animals↗
PubMed1988

Model to examine pathways of carbon flux from lactate to glucose at the first branch point in gluconeogenesis.

The first branch point in gluconeogenesis occurs at the conversion of pyruvate to oxaloacetate. To determine the amount of lactate carbon reaching glucose via the direct pyruvate carboxylase pathway versus the tricarboxylic acid cycle, adult rat hepatocytes in primary culture were incubated for 2 h with one of the following isotopic substrates: [1-14C]lactate, [U-14C]lactate, or [1,2-14C]acetate. Production of 14CO2 and [14C]glucose from each substrate was assessed. The amount of lactate carbon 2 and 3 incorporated into glucose or oxidized to CO2 was determined by subtracting values using [1-14C]lactate from those using [U-14C]lactate. After quantitation of CO2 formed from carbons 2 and 3 of lactate, the amount of these carbons incorporated into glucose via the tricarboxylic acid cycle can be determined by simple proportionality from the ratio of label incorporated into glucose or CO2 from [1,2-14C]acetate. The remaining carbons 2 and 3 of lactate incorporated into glucose are derived from the pyruvate carboxylase pathway directly. Ethanol which on oxidation provides NADH and acetate decreased lactate oxidation and enhanced the pyruvate carboxylase pathway. Glucagon increased carbon flux through both pathways but primarily through the pyruvate carboxylase pathway. In summary, a simple model is presented to examine carbon flux from lactate via the pyruvate carboxylase and tricarboxylic acid pathways during gluconeogenesis.

Animals↗
PubMed1988

Effects of pregnancy and lactation on the metabolism of bovine adipose tissue.

The incorporation of [2-14C] acetate into the triglycerides of adipocytes from bovine omental adipose tissue was at a minimum during peak lactation but increased again in late lactation. Similar but somewhat greater changes were observed for adipocytes from subcutaneous adipose tissue. In both tissues the activities of four enzymes concerned with fatty acid synthesis were lowest during peak lactation. In omental tissue lipoprotein lipase activity was lowest during peak lactation but there was a marked increase in its activity in the udder during lactation. In both omental and subcutaneous adipocytes the rate of glycerol release at peak lactation was higher than at all other stages of pregnancy and lactation. At peak lactation plasma insulin levels were low but growth hormone levels were higher than at all other stages of pregnancy and lactation. These results suggest that lipogenic precursors were diverted away from adipose tissue in early lactation and stored triglycerides were made available for use elsewhere in the body.

Acetates↗
PubMed1985

Lactation failure due to insufficient glandular development of the breast.

With the present increased incidence of breast-feeding, clinicians need to be prepared to identify and manage problems in lactation. Most problems are related to insufficient knowledge, inappropriate routines, and lack of confidence and are easily managed or prevented by prenatal education, anticipatory guidance, and adequate support. Increasing evidence exists that primary causes of lactation failure also occur and can preclude successful lactation, even among highly motivated women. Three cases are presented in which lactation failure is believed to stem from insufficient glandular tissue within the breasts. Supportive history for this entity include absence of typical breast changes with pregnancy and failure of postpartum breast engorgement to occur. Associated physical findings included a unilateral underdeveloped breast in each woman and palpable patchy areas of glandular tissue in one case. Breast diaphanography, or transillumination, substantiated clinical findings in the two cases in which it was performed. Both multiparous women had a previous unsuccessful breast-feeding experience, whereas the primiparous woman had immediate family members with a history of lactation failure. All three women benefited psychologically from the interpretation that lactation failure was not due to their breast-feeding performance, and each elected to continue nursing long-term despite the need for formula supplement. These cases are presented to emphasize that primary causes of lactation failure do exist and to alert clinicians to the historical and physical findings suggestive of inadequate glandular tissue as an etiology of previously unexplained lactation failure. Preserving the "every woman can nurse" myth contributes to perpetuating a simplistic view of lactation and does a disservice to the small percentage of women with primary causes of unsuccessful lactation.

Adult↗
PubMed1994

[The value of blood lactate determination in the postoperative phase].

The aim of this study was to investigate whether the measurement of blood lactate in the early postoperative period would be useful for an assessment of the postoperative course. For the determination of a reference curve, the lactate concentration was measured in 10 patients (control group) with uncomplicated courses of the operation which lasted for up to two hours. The investigation group included 111 patients with complicated courses of the operation and/or a duration of the operation of more than 2 hours. The reference value of lactate was 1.3 mmol/l on the average. Lactate values above 2.5 mmol/l were considered as pathological values. In spite of the high physiological range of variations of the blood lactate concentration and many factors which influenced this value, it could be shown that the blood lactate concentration enabled a good prognostic assessment of the course of the early postoperative period in intensive care patients. Intraoperative complications were followed by significantly higher lactate concentrations in the first two postoperative hours (p < 0.001). Increased lactate concentrations during the first two postoperative hours were also a significant parameter for the occurrence of postoperative complications (p < 0.001). Patients with lethal courses already showed intraoperatively increased lactate values in comparison to those patients who could be transferred to a normal ward for further recovery (p < 0.05). From the statistical point of view, patients with lactate concentrations of more than 4.0 mmol/l lasting for more than two hours after an operation had bad prognosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗