Porth's Essentials of Pathophysiology, 4e

432

Circulatory Function

U N I T 5

TABLE 18-5 The 90th and 95th Percentiles of Systolic and Diastolic Blood Pressure for Boys and Girls 1 to 16Years of Age by Percentiles for Height

Height Percentile for Boys

Height Percentile for Girls

Blood Pressure Percentile

Age (yrs)

5th 25th 75th 95th 5th 25th 75th 95th

Systolic Pressure 90th

1

94 98

97

100 104 107 110 111 115 117 121 124 128 131 135

103 106 109 113 113 117 119 123 126 130 134 137

97

98

101 105 104 108 109 113 116 120 122 126 126 130

103 107 106 110 111 115 118 122 124 128 128 132

95th 90th 95th 90th 95th 90th 95th 90th 95th 90th 95th 95th 90th 95th 90th 95th 90th 95th 90th 95th 90th 95th

101 103 107 108 112 114 117 120 124 128 132

100 100 104 104 108 112 116 117 121 121 125

102 102 105 106 110 114 117 119 123 123 127

3

100 104 105 109 111 115 117 121 125 129

6

10

13

16

Diastolic Pressure 90th

1

49 54 59 63 68 72 73 77 75 79 78 82

51 55 60 64 69 73 74 79 76 80 79 83

53 58 62 66 71 75 76 81 78 82 81 85

54 58 63 67 72 76 78 82 79 83 82 87

52 56 61 65 68 72 73 77 76 80 78 82

53 57 62 66 69 73 73 77 76 80 79 83

55 59 64 68 70 74 75 79 78 82 81 85

56 60 65 69 72 76 76 80 79 83 82 86

3

6

10

13

16

The height percentile is determined using the newly revised CDC growth charts. Blood pressure levels are based on data from the 1999–2000 National Health and Nutritional Examination Survey (NHANES) that have been added to the childhood BP database. From the National High Blood Pressure Education ProgramWorking Group on High Blood Pressure in Children and Adults. Fourth report on the diagnosis, evaluation, and treatment of high blood pressure in children and adolescents. Pediatrics. 2004;114:555–576.

aorta is another cause of hypertension in children and adolescents. Endocrine causes of hypertension, such as pheochromocytoma and adrenal cortical disorders, are rare. Hypertension in infants is most commonly asso- ciated with high umbilical catheterization and renal artery obstruction caused by thrombosis. 65 Most cases of essential hypertension are associated with obesity or a family history of hypertension. A number of drugs of abuse, therapeutic agents, and toxins also may increase blood pressure. 60 Alcohol should be considered as a risk factor in adolescents. Oral contraceptives may be a cause of hypertension in ado- lescent girls. The nephrotoxicity of the drug cyclospo- rine, an immunosuppressant used in transplant therapy, may cause hypertension in children (and adults) after bone marrow, heart, kidney, or liver transplantation. The coadministration of corticosteroid drugs appears to increase the incidence of hypertension. Diagnosis and Treatment. Children 3 years of age through adolescence should have their blood pressure taken once each year. 58 The auscultatory method using

a cuff of an appropriate size for the child’s upper arm is recommended. 58 Repeated measurements over time, rather than a single isolated determination, are required to establish consistent and significant observations. Children with high blood pressure should be referred for medical evaluation and treatment as indicated. Treatment includes nonpharmacologic methods and, if necessary, pharmacologic therapy. High Blood Pressure in the Elderly The prevalence of hypertension increases with advanc- ing age to the extent that half of people aged 60 to 69 years and approximately three fourths of people 70 years and older are affected. 29 The age-related rise in systolic blood pressure is primarily responsible for the increase in hypertension that occurs with increasing age. Pathogenesis and Risk Factors. Among the aging processes that contribute to an increase in blood pres- sure are a stiffening of the large arteries, particularly