Reference values for peak expiratory flow rate in adults of African descent.

Substantial racial differences in the values of peak expiratory flow (PEF) rate have been noted by several workers in the past. It has also been noted that applying prediction formulae derived from a Caucasian population overestimated the PEF values in Black Africans by 12%-15%. Yet reference values used up until the present, even among Black populations, are based on such formulae. This study provides new reference values for use in the Black population. They were obtained by using curvilinear formulae derived from the study of 1009 normal adult Nigerians (668 men and 341 women) between the ages of 15 years and 82 years, living and/or working in Port Harcourt, Nigeria and its hinterland.

Curvilinear formulae for predicting peak expiratory flow rate in adult Nigerians.

Predicted values of Peak expiratory flow rate (PEF) using linear formulae do not closely agree with observed trends. Predicted values tend to be higher than observed values among youths and the elderly while they are usually lower than observed values among people within the prime of life. All prediction formulae in Nigeria are linear. In this study, more fitting curvilinear formulae were derived for male and female subjects from PEF values obtained from a study of 1009 subjects made up of 668 males and 341 females between the ages of 15 and 82 years living and/or working in Port Harcourt, Nigeria and its environs. We hope that these formulae may be put to greater use since they agree more closely with the observed trends.

Haemorheological parameters in hypertensive Nigerians with and without sickle-cell trait.

Haemorheological parameters including whole blood (WBF) and erythrocyte filterability (EF), haematocrit (H'ct), haemoglobin levels (Hb) and plasma fibrinogen concentration (PFC) were measured in 61 adult Nigerians with uncomplicated essential hypertension during the course of their routine anti-hypertensive treatment. Results from these patients were compared to those of 39 age and sex-matched normotensive controls. Sixteen (26.2%) of the hypertensive patients and 6 (15.4%) of the controls had the sickle-cell trait (HbAS); the rest were normal homozygotes (HbAA). Although there were no significant difference between WBF in the HbAA-hypertensive and control groups, the former had a significantly lower EF than the latter (p less than 0.025). Both WBF and EF were highly significantly decreased in the HbAS-hypertensives (p less than 0.001). Significant differences in H'ct and Hb levels between HbAA-hypertensives and controls were attributed to sex rather than to hypertension per se. Plasma fibrinogen concentration values were consistently and significantly elevated in all hypertensives irrespective of sex or haemoglobin genotype. In contrast to the HbAA-hypertensives, all 16 HbAS-hypertensives had a persistently raised diastolic blood pressure above 90 mm Hg, suggesting that these patients are either resistant or are less responsive to conventional anti-hypertensive therapy. A more extensive follow-up study is in progress to assess the possible relationship of these parameters and blood pressure, particularly in hypertensive individuals with sickle-cell trait (HbAS).

High dose ascorbic acid in Nigerian asthmatics.

Forty-one asthmatic patients in remission were randomly allocated to two treatment groups in a double-blind trial. One group took 1 g, of ascorbic acid as one effervescent tablet once daily and the second group took a matching placebo. The asthmatics were selected from those attending the Asthma Clinic. One criterion for selection was the increase in exacerbation during the rainy season. These exacerbations were precipitated by respiratory infection. After 14 weeks, an assessment of the severity and rate of attacks showed that those on ascorbic acid suffered less severe and less frequent attacks of asthma during the study period. Plasma ascorbic acid astimations showed a significant rise in the level in those taking ascorbic acid over those on placebo. (P < 0.01). Cessation of ascorbic acid in the group taking it increased attack rates. It is concluded that high dose ascorbic acid is probably a good prophylaxis in some bronchial asthmatics.

Tetanus: conservative management made easier by combination of muscle relaxants.

Conservative management of 11 consecutive cases of tetanus with diazepam in heavy doses and methocarbamol is described. All drugs were administered intravenously through a cut-down. Patients were nursed near the nurses' station for the first 3 to 5 days when fatal complications and very severe spasms are most likely to occur. There was minimal interference with the patients and a reasonable reduction in the duration of significant spasms, and complications were minimized. No neonates were included. Severity of tetanus cannot be determined only by consideration of onset of symptoms before admission. It is suggested that a combination of muscle relaxants without heavy sedation may produce an improvement in the results of conservative management of clinical tetanus.