Literacy promotion in primary care pediatrics: can we make a difference?

BACKGROUND: Reading skills are critical to children's success in school and the increasingly technologic workforce. Children from low-income families are at risk for home environments that fail to promote emergent literacy and for reading failure. A home environment that encourages learning and parents who are involved in their children's education are important factors in school achievement. OBJECTIVE: To evaluate the effects of a literacy promoting intervention delivered by pediatric providers as part of well-child care on parent attitudes and behaviors and on child language. DESIGN/METHODS: A multicultural group of 205 low-income families with 5- to 11-month-olds were prospectively enrolled, interviewed, and randomized to intervention (n = 106) or control (n = 99) groups. Families in the intervention group received developmentally appropriate children's books and educational materials and advice about sharing books with children, while those in the control group received no books or materials relevant to literacy. After an average of 3.4 well-child visits in both groups, 153 (75%) were reinterviewed and the children's receptive and expressive vocabulary was tested using a modified version of the MacArthur Communication and Development Inventory (Short Form). Parents were asked if their child understood (receptive vocabulary) or said (expressive vocabulary) each of 100 words, half of which were in the books given. Families were found to have a Child-Centered Literacy Orientation if they mentioned reading aloud as one of their child's favorite activities or as one of their own favorite joint activities or if they usually read together at bedtime. At follow-up toddlers were 18.4 months old on average. RESULTS: Intervention and control groups had similar literacy related characteristics at baseline. There was a 40% increase in Child-Centered Literacy Orientation among intervention families compared with 16% among controls. Intervention families read more with their toddlers (4.3 vs 3.8 days/week). Both receptive and expressive vocabulary scores were higher in older intervention toddlers (18-25 months old; n = 88), but not in younger intervention toddlers (13-17 months old; n = 62). This significant effect of the intervention on vocabulary scores in older toddlers was found for both the 50 words in the books and those not in the books. After parent education, foreign birth and language proficiency, and child age were statistically controlled, the intervention remained significantly associated with higher language outcomes in older toddlers. However, when reading aloud was added to the multivariate analysis, the influence of the intervention was no longer evident, suggesting the intervention's effect on child language was mediated through increased shared reading with these toddlers. CONCLUSION: This simple and inexpensive intervention, delivered as part of well-child care, changed parent attitudes toward the importance of reading with their infants and toddlers. These intervention parents and their children read more together and this was associated with enhanced language development in older toddlers in this diverse group of low-income families.

Estimating Bacterioplankton Production by Measuring [H]thymidine Incorporation in a Eutrophic Swedish Lake.

Bacterioplankton abundance, [H]thymidine incorporation, CO(2) uptake in the dark, and fractionated primary production were measured on several occasions between June and August 1982 in eutrophic Lake Norrviken, Sweden. Bacterioplankton abundance and carbon biomass ranged from 0.5 x 10 to 2.4 x 10 cells liter and 7 to 47 mug of C liter, respectively. The average bacterial cell volume was 0.185 mum. [H]thymidine incorporation into cold-trichloroacetic acid-insoluble material ranged from 12 x 10 to 200 x 10 mol liter h. Bacterial carbon production rates were estimated to be 0.2 to 7.1 mug of C liter h. Bacterial production estimates from [H]thymidine incorporation and CO(2) uptake in the dark agreed when activity was high but diverged when activity was low and when blue-green algae (cyanobacteria) dominated the phytoplankton. Size fractionation indicated negligible uptake of [H]thymidine in the >3-mum fraction during a chrysophycean bloom in early June. We found that >50% of the H activity was in the >3-mum fraction in late August; this phenomenon was most likely due to Microcystis spp., their associated bacteria, or both. Over 60% of the CO(2) uptake in the dark was attributed to algae on each sampling occasion. Algal exudate was an important carbon source for planktonic bacteria. Bacterial production was roughly 50% of primary production.

Lysine-vasopressin in excisional treatment of burns in pigs. Decreased blood loss and earlier circulatory recovery.

The hemodynamics were monitored during 24 hours in piglets anesthetized with Pentothal-N2O/O2, submitted to 33% full-thickness skin burn and resuscitated with 2.4 ml/kg/% burn of 100 mmol NaCl in 2.5% glucose. Three groups were studied: (I) standardized burn, (II) standardized burn and excision after 5 hours, (III) standardized burn, excision and lysine-vasopressin (LVP) given as intravenous infusion in a vasopressor dose. All groups showed similar decrease of cardiac output (CO), which was about 30% 4 hours after burn. In the two groups with burn excision, however, CO recovery was earlier than in the conservatively treated group I. The improvement was significant between group III and group I. LVP led to higher CO fraction and greater blood flow to hepatic artery, reduced flow to proximal gastrointestinal tract and skin and unchanged flow to heart, kidneys and other organs 24 hours after burn. The mean blood loss during and after burn excision was greatly reduced in group III (50 g/25 kg) compared with group II (146 g/25 kg). The therapeutic implications of LVP in excisional burn treatment are discussed.

Effects of lysine-vasopressin treatment on renal function in burned pigs.

The effects of lysine vasopressin (LVP) on renal excretory function and renal blood flow were studied in anesthetized and burned pigs either treated conservatively or by early excision 5 hours after burn. Renal perfusion was measured with radioactive microspheres. Diuresis and the urinary excretion of sodium and potassium were determined. Glomerular filtration rate (GFR) was measured either as the endogenous creatinine clearance rate or the clearance rate of 51Cr-EDTA. LVP-treatment in pharmacologic doses after burn caused larger diuresis, and larger sodium and potassium excretion rates than in unburned controls and animals submitted to burn only, Renal blood flow decreased significantly early after burn whether LVP was given or not. After burn, GFR was moderately higher in the LVP-treated pigs than in the animals submitted to burn only. After 24 hours S-creatinine was lower in the pigs treated by LVP and excision of the burned tissues after 5 hours, compared with the conservatively treated animals. This implies that an active surgical approach to full thickness skin burns might support renal function. LVP-induced intrarenal effects causing increased GFR and secondary medullary interstitial electrolyte concentration and osmolar changes could be the mechanisms causing the renal functional changes found in this investigation.

The effects of lysine-vasopressin on hemodynamics during early post burn period in pigs.

In order to investigate the central and peripheral circulatory effects of a vasoactive drug, lysin vasopressin (LVP), in the early postburn period, 18 piglets were submitted to an experimental study. Anaesthesia was performed by thiopentone sodium as i.v. infusion and mechanically controlled ventilation via endotracheal intubation. Burn injury was brought about by heated metal stamps applied to the back and sides of the animals causing a full thickness skin burn corresponding to 32-35% of the total body surface area. Cardiac output decreased significantly after burn and so did organ blood flow, measured with radioactively labelled microspheres, especially after 4 hours. LVP-infusion did not further decrease cardiac output after burn but decreased the blood flow to the skin, carcass and proximal gastrointestinal tract. The liver perfusion was increased, while the flow in the other organs was not different from that in burned pigs not given LVP. The therapeutical implications are discussed.

Haemodynamic effects of labetalol-induced hypotension in the anaesthetized dog.

Central haemodynamic changes and regional blood flow were studied using the microsphere technique, during labetalol-induced hypotension in dogs anaesthetized with pentobarbitone and fentanyl. Labetalol 15 mg kg-1 decreased mean arterial pressure from an average of 88 mm Hg to 47 mm Hg. Mean pulmonary arterial pressure was unchanged. Cardiac output was reduced by decrease in stroke volume, while heart rate remained unchanged. Myocardial blood flow decreased approximately in parallel with left ventricular work. Perfusion of the brain and kidneys was unchanged.

Deliberate arterial hypotension in plastic surgery for the reduction of hypertrophic breast: a critical appraisal of surgical ischaemia and haemodynamic changes during sodium nitroprusside infusion.

Deliberate hypotension was used to attain surgical haemostasis in thirteen patients undergoing plastic and reconstructive surgery on breast, with an 0.01% sodium nitroprusside (SNP) infusion and concomitant deep neuroleptanaesthesia. The mean surgical haemorrhage was 217 ml in the hypotensive group and when compared with a group of 13 normotensive patients, in whom the average blood loss was 688 ml, the difference was highly significant. A continuous monitoring of the changes in the circulatory dynamics, by electrical impedance plethysmography which was sustained before, during and after the application of SNP, revealed considerable enhancement in the cardiac output as well as the peripheral blood flow of all patients investigated. There was a moderate increase in the stroke volume of a majority of patients. The total systemic resistance was greatly diminished in all the patients submitted to hypotensive anaesthesia with nitroprusside. The clinical criteria were also compared with another group of fourteen patients where arfonad (trimetaphan) was employed to induce hypotension. The difference in bleeding between the two hypotensive groups was insignificant. Neither sodium nitroprusside nor arfonad induced hypotension necessitated any blood transfusion, during or after the surgery.

Ketamine infusions: pharmacokinetics and clinical effects.

The clinical effects and pharmacokinetics of ketamine, administered as an i.v. infusion, were studied in 31 patients. Anaesthesia was induced with ketamine 2 mg kg-1 i.v. and maintained using an i.v. infusion of ketamine, supplemented by nitrous oxide. The plasma concentrations of ketamine, nor-ketamine and dehydro-nor-ketamine were analysed using gas-liquid chromatography. The average maintenance dose of ketamine was 41 +/- 21 microgram kg-1 min-1, but there was an obvious decrease in the dose required as anaesthesia progressed. This dose gave a stable plasma concentration of ketamine of 9.3 +/- 0.8 mumol litre-1. Patients recovered at 2.7 +/- 0.9 mumol litre-1. Plasma half-life of ketamine was 79 +/- 8 min. Maximum concentration of nor-ketamine was 4.7 +/- 2.4 mumol litre-1 and of dehydro-nor-ketamine 3.2 +/- 1.9 mumol litre-1. There were transient increases (15-30% of pre anaesthetic values) in arterial pressure, heart rate and cardiac output during operation. No post-operative respiratory depression was seen.

Haemostatic effect of triglycylvasopressin on bleeding from gastric mucosal lesions in the rat.

The haemostatic effect of triglycylvasopressin (TGLVP) on the gastric mucosa was evaluated in an experimental model in the rat. TGLVP was found to reduce the bleeding significantly compared with the untreated controls. The haemostatic effect was most prounounced and prolonged when 200 microgram/kg b.w. was given intravenously. The clinical application of this finding is discussed.

Distribution of cardiac output in burned mice after treatment with triglycylvasopressin.

Earlier published results have shown an increased 5-day survival in burned mice treated with Triglycylvasopressin. In order to analyze the cause of the increased survival, the distribution of cardiac output was studied in 51 mice divided into three groups. The investigation was performed on the 5th day after burn using a soluble indicator technique (86Rb). The first group consisted of unburned animals. In the second and third groups, a standardized burn of 15% of the body surface was undertaken. The animals in the second group were used as controls and received isotonic saline solution for 5 days. The third group were used as controls and received isotonic saline solution and in addition Triglycylvasopressin, a vasopressin with prolonged effect, 100 microgram/kg body weight subcutaneously twice a day in such a way that the total volume of fluid was identical in the different groups. Cardiac output distribution showed an increased fraction to kidney, liver and small bowel and a decreased fraction to carcass in the Triglycylvasopressin-treated animals compared to burned controls.

Hemodynamics during superficial thiopental anesthesia in the dog.

Radioactive microspheres, labeled withe ytterbium (169Yb), strontium (85Sr) and cerium (141Ce) were used in an investigation of the cardiovascular response to superficial thiopental anesthesia. The course was followed for 90 min and measurements were carried out 30, 60 and 90 min, respectively. Between 30 and 60 min of anesthesia there was a slight decrease in cardiac output and left ventricular work. The blood flow was reduced to the lungs, kidneys and the liver. Between 60 and 90 min there were, except for the coeliac artery and total liver, no further changes, which indicated a circulatory steady state.

The hemodynamic effect of halothane in the normovolemic dog.

With the aid of radioactive microspheres (labeled with 169Yb, 85Sr and 141Ce, respectively), the effect of halothane anesthesia on circulation was studied for 30 min and (group A) for 120 min of halothane anesthesia in thiopental-sedated dogs. Measurements were also carried out on recovery from halothane anesthesia. Besides such well-known general circulatory changes as reduction in cardiac output, pulse rate, left ventricular work, arterial mean blood pressure and left atrial mean blood pressure, in both groups there was also a reduced coronary blood flow. The flow to the lungs, kidneys and the brain was well preserved, despite the reduction in both the cardiac output and arterial mean blood pressure. The flow to the liver, however, did not change during short halothane anesthesia; but during long anesthesia there was a marked reduction, due mainly to a decrease in the flow to the preportal area. On recovery from halothane anesthesia, the changes had mostly returned to the preanesthetic values.

The effect of halothane on the distribution of cardiac output and organ blood flows in the hemorrhagic, hypotensive dog.

Halothane was given to dogs which had been bled to an arterial mean blood pressure of 60 mmHg, and the circulatory effects were studied with the aid of the radioactive microsphere technique. The cardiac output and coronary blood flow were well maintained, whereas the arterial mean blood pressure was slightly, and the stroke volume markedly increased, indicating an improved heart function. The blood flows to the brain, lungs, liver and kidneys were well preserved throughout the anesthesia. The effect of retransfusing the withdrawn blood was also studied, and it resulted in an increased cardiac output, arterial mean blood pressure and increased blood flows to the heart, lungs, spleen, bowel and liver.

The effect of halothane on the distribution of cardiac output and organ blood flow in the hypovolemic dog.

The circulatory effect of halothane anesthesia given to moderately hypovolemic dogs (blood loss 25 ml/kg b.w.) was investigated using the radioactive microsphere technique. The effect of the anesthetic was reflected by a decrease in the arterial mean blood pressure and a reduced blood flow to the heart, whereas the blood flows to other organs did not change significantly but were well preserved in vital organs (brain, kidneys, liver and lungs). The effect on the circulation of reinfusing the withdrawn blood was also studied.

Studies on methods for determination of the distribution of cardiac output in the mouse.

Different techniques for determining cardiac output distribution in the mouse have been studied. The soluble indicator technique using injection of rubidium on the right side of the heart was found to give a satisfactory reproducibility which made it possible to determine cardiac output fractions in the normal mouse. The use of radioactivity-labelled microspheres, which must be injected on the side of the heart, was found to give unreliable and non-reproducible results. This was due to difficulty in depositing the microspheres into the left ventricle both when a catheter was inserted via the right carotid artery, or by means of cardiac puncture.