Efficacy of histamine H1 and H2 receptor blockers in the anesthetic management during operation for hydatid cysts of liver and lungs.

We studied the effects of preoperative administration of histamine (H1 and H2) receptor blockers on hemodynamic changes in two groups of patients having operation for hydatid cyst. Patients in group 1 received no antihistaminics, whereas those in group 2 were pretreated with both H1 (diphenhydramine) and H2 (cimetidine) receptor blockers. Even though there were significant hemodynamic responses associated with spillage of hydatid cyst contents in both groups, the hemodynamic changes were significantly less in the patients who had received histamine receptor blockers. We conclude that the preoperative administration of H1 and H2 receptor blockers to patients having hydatid cyst surgery is beneficial.

Effect of normal and preeclamptic pregnancies on the oxyhemoglobin dissociation curve.

Hemoglobin affinity for oxygen in whole blood of ten normal nonpregnant women, ten normal pregnant women at first trimester, ten normal pregnant women at second trimester, 24 normal pregnant women at or near term, and 14 pregnant women with preeclampsia at or near term was studied. The mean P-50 values for normal nonpregnant women, normal pregnant women in first trimester, second trimester, and at or near term were 26.7 +/- 0.11 mmHg, 27.8 +/- 0.08 mmHg, 28.8 +/- 0.17 mmHg, and 30.4 +/- 0.20 mmHg, respectively. The mean P-50 of pregnant women with preeclampsia at or near term was 25.1 +/- 0.38 mmHg. It is concluded that in normal pregnant women there was a significant shift of P-50 to the right compared with the normal nonpregnant women (P less than 0.01), and the extent of this shift to the right is directly related to the duration of the pregnancy. In addition, preeclamptic parturients showed a significant shift of P-50 to the left when compared with normal pregnant women at or near term (P less than 0.001).