A standard protocol for blood pressure measurement in the newborn.

OBJECTIVES: Improvements in neonatal care have resulted in increasing survival of extremely premature infants whose hospital course often runs into weeks or months. Some interventions during the acute care of these neonates, such as umbilical catheterization and use of steroids, not infrequently result in elevation of blood pressure (BP). It is, therefore, essential that these infants be monitored accurately for possible hypertension during their convalescence. Unfortunately, normative data on BP in this population are scant and comparison of data from various studies is hampered by methodologic differences in design. Studies in adults address the necessity for a restful state, adopting a comfortable position, and attempts to reduce the startle response to initial cuff inflation. Studies in the newborn using the oscillometric technique have not addressed these concerns. A standard BP measurement protocol was studied to determine the effect of ensuring a restful state, startle response to cuff inflation, and infant position on BP in clinically stable low birth weight infants after the first week of life. STUDY DESIGN: The Dianamap oscillometer was used to measure BP in infants with a birth weight <2500 g between 7 and 42 days postnatal age. Each infant was studied only once when they were clinically stable. BP was measured in two positions, prone and supine, in random order. Infants were studied at least 11/2 hours after their last feeding or medical intervention. An appropriate sized cuff was applied to the right upper arm and the infant was positioned according to randomization. The infant was then left undisturbed for at least 15 minutes or until the infant was sleeping or in a quiet awake state. Three successive BP recordings were taken at 2-minute intervals. The infant's position was then reversed and another 15 minutes of quiet time was allowed. Thereafter, a second set of three successive BP recordings were obtained. The most recent routine nursing BP measurement was also recorded. Data were analyzed using analysis of variance and are presented as means and standard errors of the mean. RESULTS: Sixty-four infants were studied. Birth weights ranged from 901 to 2423 g and gestational ages from 26 to 37 weeks. Overall, mean BP was significantly lower in the prone than supine positions (45.7 +/- 0.7 vs 47.8 +/- 0.8 mm Hg, P < .002). In either position, the first measurement was significantly higher than the third (average difference was 3 mm Hg, P < .003). In general, the relationships among position and order of measurement were similar for systolic and diastolic BP. Mean BPs obtained by routine nurse measurements were significantly higher than those in either position using our standard protocol (54.4 vs 47.0 or 49.1 mm Hg, P < .003). Moreover, the routine nurse measurements varied more widely than did those obtained using the standard protocol. The standard deviation for the routine mean BP measurements by nurses was 11.4 compared with 6.8 and 8.2 for the first measurements in the prone and supine positions, respectively, with the standard protocol. The mean BP measurements made in the supine position (the highest measurements obtained) using the standard protocol were also significantly lower than published values: 57 of 64 measurements were less than the average mean BP for age described by Tan (J Pediatr. 1988; 112:266-270). CONCLUSION: The statistically significant difference between the prone and supine position and among successive measurements in each position are not clinically relevant. The clinically significant differences between measurements obtained with this standard protocol and routine nursing measurements or published data are the result of ensuring a restful state after cuff application. We believe that measurements thus obtained are more representative of true resting BPs in these infants. (ABSTRACT TRUNCATED)

Respiratory syncytial virus infections in malnourished children.

The prevalence of respiratory syncytial virus (RSV) infection among severely malnourished children was studied at the University of Benin Teaching Hospital, Benin City, Nigeria at a time when the infection was known to be prevalent in the community. Nasopharyngeal washings were obtained from subjects on admission and thereafter every 4 days until discharge. RSV was detected by ELISA technique. Of 20 well nourished children who served as controls, 11 were ELISA-positive for RSV (55%). Eight (16%) of the 51 patients who were malnourished were ELISA-positive, four of whom (8%) had nosocomial infection. Fever and rhinitis were the most common presenting features in the RSV-infected malnourished children. None of the children showed any clinical or radiological signs of lower respiratory tract infection. Malnourished children appear not to be at increased risk of RSV infection, and those who contract the infection usually do not manifest severe disease.

Obesity, body fat distribution, and blood pressure in Nigerian and African-American men and women.

This article describes a study that assesses body fat distribution patterns in Nigerian and African-American males and females and determines the association between body fat distribution patterns and blood pressure in young adults of differing geographical and ethnic backgrounds. The study population was comprised of 275 African Americans (92 males and 183 females) and 282 Nigerians (219 males and 63 females). The mean ages for the African-American males and females were 18.7 and 18.9 years, respectively, compared with 21 and 19.2 years for the Nigerian males and females. African Americans were more likely to be obese and overweight compared with their Nigerian counterparts. However, there were no significant differences between the two ethnic groups within gender for body fat distribution patterns based on waist-to-hip ratio. Despite being leaner, the Nigerians had higher diastolic blood pressures than the African Americans. There were no significant associations observed between blood pressure and waist-to-hip ratio for either the Nigerian or the African-American males or females, and body mass index was associated consistently with blood pressure only among the African Americans. These findings suggest that body mass index, a general indicator of obesity, is a better correlate of blood pressure than the waist-to-hip ratio among African Americans.

Sex and ethnic differences associated with urinary sodium and potassium in African-American US white and Nigerian college students.

BP and urinary sodium and potassium were assessed in 183 African-American, 113 US white and 72 Nigerian college students. SBP was higher in African-American males compared with Nigerian and US white males (123.1, 117.6 and 115.7 mmHg, respectively, P < 0.05). There were no significant differences observed between African-American and white male students in overnight urinary excretion rates of sodium and potassium. In contrast, African-American females excreted more sodium (41.0 vs. 31.3 mEq per 8 hours, P < 0.01) and potassium (12.0 vs. 8.9 mEq per 8 hours, P < 0.05) compared with white females. Only among the white students was a significant sex difference observed in urinary electrolyte excretion rates, where males excreted at higher rates than females. Multiple regression models for the African-Americans revealed that potassium explained only 4% of the SBP variance. Among the US whites and Nigerians, sodium explained 4.9% and 6.8%, respectively, of the DBP variance.

Hemopexin: a unique genetic polymorphism in populations of African ancestry.

Using isoelectric focusing and immunoblotting techniques, we have screened 937 plasma or serum samples from Nigerian blacks (N = 380), Papua New Guineans (N = 110), Aleuts (N = 62), Mayans (N = 139), Dogrib Indians (N = 45), and Eskimos from Kodiak and St. Lawrence islands (N = 201) for the hemopexin (HPX) polymorphism. We compared these data with our previously published data for US whites (N = 267) and US blacks (N = 194). Except for Nigerian blacks and US blacks, HPX was found to be monomorphic for the common HPX*1 allele in all populations tested. In addition to the commonly occurring HPX*1 allele, two other less common alleles, HPX*2 and HPX*3, were observed with respective frequencies of 1.8% and 4.6% in US blacks and 1.7% and 9.0% in Nigerian blacks. These data strongly suggest that the HPX*2 and HPX*3 alleles are unique alleles restricted to the black gene pool and are of potential significance in microevolutionary studies and in defining African admixture in hybrid populations. In addition to their importance in anthropogenetic studies, these unique HPX mutations also have potential biological significance in hemolytic disorders.

Nutritional status of urban Nigerian school children relative to the NCHS reference population.

The present study assessed the growth problems in an indigenous African population of Nigerian urban public school children. The study population consisted of 1390 Nigerian children (predominantly Igbo), 718 boys and 672 girls, ages 4-10 years. Compared to the National Center for Health Statistics (NCHS) reference population, the Nigerian children had an excess prevalence of both short stature and underweight. The prevalence of short stature was 14.2% for the boys and 17.4% for the girls. Approximately 20% of the children were underweight whereas less than 1% were considered overweight. These data demonstrate an excess of both acute and chronic malnutrition relative to the NCHS reference population.

PIP: In 2 urban primary schools in Benin City, Nigeria, over a 3-month period, research assistants came to the classrooms of 1390 children aged 4-10 years to take anthropometric measurements so researchers could compare the nutritional status of these school children with that of a US reference population. The Nigerian school children were much shorter than the US reference population. Specifically, boys were at the 32.4 percentile and girls were at the 31.5 percentile. Further, more than 66% of the children fell in percentiles lower than the 40th percentile for height for age. 19.9 and 19.7 were the mean weight for age percentiles for boys and girls. Almost 85% of the children were below the 40th percentile of the US reference population for weight for age. More than 80% were below the 40th percentile for weight for height. 14.2% of boys and 17.4% of girls were short for their age. 19.5% of boys and 21.1% of girls were undernourished (i.e., underweight). Just less than 1% were overweight. The researchers called for further research to learn more about interpretation of growth patterns and problems between developing and developed countries, since a US reference may not be suitable for all populations.

The sickle gene: a marker for blood pressure?

Blood pressure patterns were studied in 224 Nigerians comprising 22 families with at least one child with sickle cell anemia (SS) and 18 families without sickle cell anemia (AA) in a community with a high frequency of the sickle trait (AS). Among the offspring (n = 162; mean age: 10.1 years), systolic blood pressure did not differ between the SS, AS, or AA groups. However, the SS group had significantly lower diastolic blood pressure than the AS or AA groups (60.6 versus 66.5 and 65.4 mm Hg, respectively; P < .01). After controlling for genotype, age, body mass index, and sex, regression analysis revealed that age was the only independent correlate of blood pressure.

Pattern of bacteraemia in febrile children with sickle cell anaemia.

A total of 166 episodes of fever in 162 children with sickle cell anaemia (SCA) aged between 6 months and 16 years who presented with rectal temperatures > or = 38.3 degrees C were studied for bacteraemia. Non-sicklers of similar ages and with similar temperatures were also studied as controls. Bacteraemia occurred in 32.5% (54) of children with SCA and in 26% (39) of controls. Gram-negative bacteria were the predominant organisms (70.4%) in SCA. The commonest organisms isolated were Salmonella (25.9%), Klebsiella (25.9%) and Staphylococcus aureus (22.2%). Gram-positive bacteria were the predominant organisms (51.3%) in controls, with Staphylococcus aureus accounting for 41% of all organisms isolated. In both groups, the incidence of bacteraemia decreased in children after the age of 10 years. Use of antibiotics prior to presentation in hospital was commoner among children with SCA (47.6%) than controls (14.7%). Antimicrobial agents were detected in the urine of 12 children with SCA and four controls whose parents denied prior antibiotic usage. The predominant organisms isolated were sensitive to gentamicin and 3rd-generation cephalosporins.

Factors associated with hypertension in Nigerian civil servants.

BACKGROUND: Study of hypertension in segments of West African populations in transition toward Westernization may lead to better understanding of the high risk for hypertension among Westernized blacks. METHODS: Five hundred fifty-nine urban civil servants, ages 25-54, were recruited from six ministries of Bendel State, Nigeria. Blood pressure, physical measurements, urinary protein and glucose, fasting blood glucose, and demographic data were collected at the workplace. Subjects were classified as senior staff (professionals or administrators) or junior staff (non-administrators). RESULTS: Among 172 male senior staff, the age-adjusted rate of hypertension (diastolic blood pressure > or = 90 mm Hg, systolic blood pressure > or = 140 mm Hg, or on an antihypertensive medication) was 43% and occurrence rose dramatically from 21 to 63% across age groups 25-34 to 45-54, respectively. Among 266 male junior staff, the age-adjusted rate of hypertension was 23%, and occurrence did not rise with age. Logistic regression showed that body mass index (kg/m2), age, alcohol drinking, and being senior staff were all independently related to hypertension in men. On the other hand, the age-adjusted rate of hypertension in 121 women was 20% and was significantly related only to body mass index. CONCLUSION: Male urban civil servants appeared to have a risk for hypertension similar to that of U.S. black males. Age, body mass index, alcohol drinking, and other unidentified factors related to higher socioeconomic status were strong determinants of hypertension in this population.

Malarial parasitaemia in febrile children with sickle cell anaemia.

One-hundred-and-sixty-six episodes of fever in 162 children with sickle cell anaemia (SCA) aged 6 months to 16 years, presenting to the children emergency room of the University of Benin Teaching Hospital, Nigeria with rectal temperature greater than or equal to 38.3 degrees C were studied for malarial parasitaemia. Non-sicklers of similar ages and with similar temperatures were also studied as controls. Malarial parasitaemia was documented in 9 per cent of children with sickle cell anaemia, and 29 per cent of controls (P less than 0.0001). Bacteraemia occurred in 33 per cent of children with SCA and 26 per cent of controls (P greater than 0.10). Bacteraemia was, therefore, the commonest cause of pyrexia in febrile children with sickle cell anaemia on antimalarial prophylaxis. It is suggested that children with SCA on regular anti-malarial prophylaxis who present with significant pyrexia should be carefully screened for bacterial infection and appropriate anti-microbial therapy instituted.

Tracking of blood pressure and anthropometric measures in Nigerian children.

Persistence in ranks (tracking) for blood pressure and anthropometric measures over a one year period was examined in 208 Nigerian children (age 6-17 years). Systolic blood pressure tracked better than diastolic blood pressure (r = 0.52 to 0.72) and r = 0.25 to 0.55, respectively). For systolic blood pressure, 56.5%-70.6% of the Nigerian children remained in the top tertile after one year compared with 45.5%-69.2% for diastolic blood pressure. Weight showed the strongest correlation over the one year period (r = 0.88 to 0.97), whereas skinfolds demonstrated the weakest association (r = 0.54 to 0.82). The association between anthropometric measures at baseline and blood pressure one year later revealed for both males and females that height and weight were positively and significantly correlated with blood pressure.

Nosocomial respiratory syncytial virus infection in a newborn nursery.

The nosocomial spread of respiratory syncytial virus (RSV) was studied in a newborn nursery in Benin City, Nigeria at a time the virus was known to be highly prevalent in the community. Nasopharyngeal washings were obtained from babies on admission and, thereafter, every 4 days until discharged. Questionnaires were administered to medical personnel with upper respiratory tract infection (URTI). RSV was detected by an ELISA technique. A total of 56 babies were studied, made up of 33 preterm and 23 full term babies. Fourteen of the 56 babies (25%) developed RSV infection. Eleven babies (20.8%) acquired the infection nosocomially. The infected babies were all symptomatic and some had significant morbidity. One preterm baby died following acquisition of RSV. The study demonstrated that medical personnel working in our newborn nursery were a major contributor to the spread of nosocomial RSV infection. Babies hospitalized for more than 4 weeks were more likely to acquire RSV infection. Control measures are outlined for the reduction of nosocomial spread of RSV infection in our newborn nursery.

Blood pressure in Nigerian college males.

Hypertension is a major cause of morbidity and mortality in US black populations. There are however limited data available on college educated blacks in either the United States or Africa. The purpose of the present study was to examine blood pressure and its correlates in a Nigerian college population in comparison with US data. The study population comprised 211 Nigerian male college students (mean age, 20.9 years). The means and standard deviations for systolic and diastolic blood pressures among the Nigerians were 119.9 (12.6) and 73.3 (10.0) mm Hg, respectively. Weight, height, and body mass index means for the Nigerians were 133.6 pounds, 68.5 inches, and 20.1 kg/m2, respectively. Compared with US college-educated blacks, the Nigerians had higher systolic blood pressures but were leaner than their US counterparts. There was however a significant positive correlation between weight and systolic blood pressure for the Nigerians, which was similar to that observed among US college students. These data suggest that in a lean population, the Nigerian males' weight is still an important correlate of blood pressure as is seen in the US.

Factors related to blood pressure among urban Nigerian workers.

This cross-sectional study of urban, Nigerian civil servants found that age, body mass index, alcohol drinking and high socioeconomic status were all positively and independently related to blood pressure among 438 males. Among 121 females, only body mass index was significantly related to blood pressure.

Blood pressure and other cardiovascular disease risk factors in black adults with sickle cell trait or glucose-6-phosphate dehydrogenase deficiency.

In this study, we examined the relationship of two common genetic markers in black populations, sickle cell trait and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency, to cardiovascular risk factors. The subjects were Nigerian civil servants in Benin City, Nigeria. We measured blood pressure, height, weight, sickle cell hemoglobin, G-6-PD, proteinuria, microalbuminuria and fasting serum cholesterol, high-density lipoprotein cholesterol (HDL), triglycerides, apoprotein (APO) AI, and APO B. Data were collected on age, alcohol consumption, cigarette smoking, job status, and years lived in an urban area. There were 257 males (3 SS hemoglobin, 73 AS, 181 AA) and 69 females (23 AS, 46 AA). In comparing cardiovascular risk factors, males differed only in percent of smokers (31.5 in AS vs. 17.8 in AA, P less than 0.01). Among females, only high-density lipoprotein (HDL) cholesterol differed (61.5 mg/dl in AS vs. 52.4 in AA, P less than 0.01). We hypothesize that females with sickle cell trait are more likely to use oral contraceptives than nontrait females. If so, the high-estrogen oral contraceptives available in Nigeria could elevate HDL. G-6-PD deficiency status among males (52 deficient, 207 nondeficient) and females (1 deficient, 5 carriers, 65 nondeficient) was not related to any of the cardiovascular risk factors. We conclude that sickle cell hemoglobin trait and G-6-PD deficiency are not useful genetic markers for risk factors for cardiovascular disease.

Assessment of cardiovascular risk factors in Nigerian students.

The present study assessed the prevalence of cardiovascular risk factors in 65 Nigerian medical students attending the University of Benin, Benin City, Nigeria. Their ages ranged from 17 to 28 years with a mean age for men of 20.9 years and for women of 18.8 years. Approximately 8% of the men and 0% of the women were current cigarette smokers, whereas alcohol use was observed in 14.6% of the men and in 0% of the women. The Nigerian men had significantly higher diastolic blood pressures than did American black and white men. Compared to American black men, the Nigerian men had considerably lower total cholesterol and triglyceride concentrations. The Nigerian women did not differ from American black women with respect to total cholesterol, but had significantly lower triglyceride concentrations.

Seasonal variation in respiratory syncytial virus infections in children in Benin-City, Nigeria.

The seasonal variation in respiratory syncytial virus (RSV) infections in children was examined in Benin City. Nasopharyngeal washes were obtained from children under 3 years hospitalised for acute lower respiratory infections during two seasons - rainy season (June-August) and dry season (December-February). RSV surface antigen was identified by ELISA. 54% of patients in the rainy season were ELISA positive for RSV compared to 8.8% during the dry season. Clinical features in the RSV infected patients were not different between the two seasons and were similar to that reported from temperate climates. It is concluded that RSV infections occur all year round with a peak during the rainy season.

Chloroquine absorption in children from polyethylene glycol base suppositories.

Chloroquine phosphate (CP) has been formulated in a suppository base consisting of polyethylene glycol, PEG 1000 and PEG 6000 (7:3) with 0.5% polysorbate 80 included as an absorption promoter. Peak chloroquine blood levels in children (mean body weight 10 kg, age 21 months) were 0.67 +/- 0.08 micrograms/ml (after 200 mg CP) and 1.06 +/- 0.23 micrograms/ml (after 300 mg CP) following rectal administration of the suppositories. Prior to drug administration, the base level chloroquine was 0.30 +/- 0.02 micrograms/ml. Elimination half lives calculated from the rapid phase of log concentration-time curves were 3.3 h (after 200 mg CP) and 2.7 h (after 300 mg CP), respectively. Based on literature evidence the blood levels obtained with the 300 mg CP suppositories would be therapeutic in the management of malaria and rheumatoid disease.

Bacterial growth in expressed breast-milk.

We determined the degree of bacterial contamination and the rate of bacterial growth in expressed breast-milk stored in a tropical environment with high ambient temperatures and humidity. Colostrum or mature milk obtained from mothers who were delivered preterm or at term was stored at room temperature (27-32 degrees C) and in a refrigerator (4 degrees C) over a 24-h period. Bacterial isolates represented normal skin flora. Our study showed that colostrum was more inhibitory than mature milk, and term colostrum more so than preterm colostrum. At room temperature, mature milk from term mothers could be stored for 6 h without a significant increase in bacterial counts. Term colostrum could be stored for 12 h without significant bacterial growth. Preterm milk could be stored for 4 hr. Our findings should be of practical value to lactating mothers without access to refrigerators.

Breast milk composition and bile salt-stimulated lipase in well-nourished and under-nourished Nigerian mothers.

Breast milk was analysed in 9 under-nourished Nigerian mothers and 23 well-nourished mothers who served as controls. Milk from the under-nourished mothers contained adequate amounts of lactose and total triglycerides, but had significantly lower bile salt-stimulated lipase activity (BSSL); their mean BSSL activity was only about 50% of the activity in milk from the control group. Total milk protein was also significantly lower than for the controls (1.45 vs. 1.09 g/dl, respectively; P less than 0.01). Our findings may have nutritional implications for breast-fed infants of under-nourished nursing mothers.