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J C Berman

Publications and source records attributed to J C Berman.

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Altered blood pressure course during normal pregnancy and increased preeclampsia at high altitude (3100 meters) in Colorado.

OBJECTIVE: Our purpose was to determine the case incidences of preeclampsia at low and high altitudes and whether maternal blood pressure course during pregnancy differs between low and high altitudes. STUDY DESIGN: This was a retrospective cohort study of pregnancies in sociodemographically matched communities at low and high altitudes in Colorado; each community had a small hospital served by family practitioners and was located >100 miles from major urban areas. Included were consecutive singleton pregnancies of women without chronic disease that resulted in live-born infants at >28 weeks' gestation during an 18-month period (n = 116 at 1260 m, n = 93 at 3100 m). Clinic and hospital medical records were searched and data pertaining to hypertensive complications of pregnancy and serial blood pressure measurements were abstracted. RESULTS: Despite similar maternal risk factors, the case incidences of preeclampsia were 16% at 3100 m and 3% at 1260 m. As in sea-level pregnancies, mean blood pressure fell until week 20 in normotensive pregnancy at 1260 m. Mean pressure rose linearly, however, in normotensive women at 3100 m and in women with preeclampsia at both 1260 m and 3100 m. High altitude acted independently of known risk factors and yielded an odds ratio for preeclampsia of 3.6 (95% confidence interval 1. 1-11.9). Birth weight was 285 g lower at 3100 m despite similar gestational ages. CONCLUSION: The normal pregnancy-associated fall in blood pressure was absent at 3100 m, even in women who remained normotensive. The incidence of preeclampsia was increased at high altitude. Residence at high altitude interferes with the normal vascular adjustments to pregnancy, increasing the incidence of preeclampsia, and is perhaps analogous to other conditions that decrease uteroplacental oxygen delivery.

Adolescent↗

The Berman airway.

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Anesthesiology↗

Alterations in uteroplacental blood flow precede hypertension in preeclampsia at high altitude.

High-altitude residence during pregnancy is associated with an increased incidence of preeclampsia. To determine whether uteroplacental blood flow was reduced and pelvic blood flow distribution altered before the onset of hypertension, we measured common iliac (CI), uterine (UA), and external iliac (EI) artery flow velocities (FV), indexes of flow distribution, and blood volume (BV) at week 12, 24, and 36 of pregnancy and 6 mo postpartum in 23 normotensive, 7 preeclamptic, 5 transiently hypertensive, and 3 chronically hypertensive residents of 3,100 m. Normotensive women had a progressive increase in CIFV and UAFV, decrease in EIFV, redistribution of CIFV from the EI to the UA, and increase in BV with advancing pregnancy. Preeclamptic women attained maximal UAFV and redistribution of CIFV from the EI to the UA well before the onset of hypertension and, unlike normotensive women, showed no further increases near term. Plasma volume increment with pregnancy related to the fall in the EIFV/CIFV ratio. Transiently hypertensive women resembled normotensive subjects in the parameters measured, whereas chronically hypertensive subjects resembled preeclamptic subjects. We concluded that preeclamptic vs. normotensive pregnant residents of high altitude had less redistribution of CI flow to the UA and no increase in UA blood flow near term. That these differences were present before the onset of hypertension supports the concept that preeclampsia is characterized by an incomplete vascular adjustment to pregnancy.

Adult↗

Blood volume expansion, preeclampsia, and infant birth weight at high altitude.

Low blood volume (BV) during pregnancy is associated with intrauterine growth retardation and preeclampsia, which are more common at high altitude (HA) than at low altitude. We hypothesized that reduced BV expansion during pregnancy predisposed some women to develop preeclampsia and/or have lower-birth-weight infants at HA. BV was lower in 34 HA residents (3,100 m) than in 22 moderate-altitude residents (1,600 m) while nonpregnant (58.3 +/- 1.2 vs. 72.3 +/- 1.3 ml/kg; P < 0.001) and 36 wk pregnant (69.9 +/- 1.9 vs. 83.3 +/- 3.6 ml/kg; P < 0.01). BV fell between weeks 24 and 36 of pregnancy, and total BV increment with pregnancy was less in women who developed preeclampsia or transient hypertension at HA (n = 12). At HA, total blood and plasma volume expansion and arterial O2 saturation correlated negatively with the highest mean arterial pressure recorded during pregnancy (r = -0.73, P < 0.01 and r = -0.58, P < 0.01, respectively). Total BV and late pregnancy change in BV correlated positively with infant birth weight. We concluded that BV expansion in normotensive pregnancy at HA vs. moderate altitude was similar but that nonpregnant BV was less among HA women, accounting for the low BV in pregnancy. HA women who developed preeclampsia or transient hypertension had less BV expansion, particularly during the third trimester, which was associated with smaller infants.

Adult↗