ABSTRACT
Objective:To determine the dose-effect relationship of norepinephrine in the treatment of hypotension after spinal anesthesia in cesarean section.Methods:Ninety American Society of Anesthesiologists physical status Ⅰ or Ⅱ parturients who were at full term with a singleton fetus, body mass index of 20-35 kg/m 2, blood pressure 100-140 mmHg, heart rate 60-100 beats/min, scheduled for elective cesarean section, were divided into 6 different doses of norepinephrine groups (NE2, NE4, NE6, NE8, NE10 and NE12 groups) using a random number table method, with 15 cases in each group.The maternal basal systolic blood pressure was measured after entering the operating room.Anesthesia was performed by injecting hyperbaric bupivacaine 9 mg into the subarachnoid space over 45 s. When hypotension occurred for the first time after anesthesia (systolic blood pressure was lower than 80% of the baseline value), norepinephrine 2, 4, 6, 8, 10 and 12 μg (diluted to 5 ml in normal saline) were intravenously injected in NE2, NE4, NE6, NE8, NE10 and NE12 groups, respectively.Systolic blood pressure was measured at 60 s after completion of injection.The effective treatment of hypotension was defined as the recovery of systolic blood pressure to more than 80% of the baseline value.The logistic regression analysis method was used to draw the dose-effect curve of norepinephrine in treating hypotension after spinal anesthesia in cesarean section.The median effective dose (ED 50), 95% effective dose (ED 95) and 95% confidence interval (CI) were calculated.The time to first hypotension, effective treatment of hypotension, and occurrence of bradycardia and nausea and vomiting after intravenous injection of norepinephrine were recorded.The Apgar scores of the neonates at 1 and 5 min after birth were recorded.The umbilical artery blood samples of neonates were collected immediately after cutting the cord for blood gas analysis. Results:There was no significant difference in the incidence of maternal basal systolic blood pressure, time to first hypotension, bradycardia, and nausea and vomiting among the six groups ( P>0.05). The rate of effective treatment of hypotension increased with the increase of the dose in the six groups ( P<0.05). There was no significant difference in Apgar score and indexes of umbilical artery blood gas analysis at 1 and 5 min after birth among the six groups ( P>0.05). The ED 50 (95% CI) of norepinephrine in the treatment of hypotension after spinal anesthesia in cesarean section was 4.0 (3.0 to 5.0) μg, and the ED 95 (95% CI) was 11.8 (8.9-20.4) μg. Conclusion:The ED 50 and ED 95 of norepinephrine are 4.0 and 11.8 μg, respectively, when used for treating hypotension after spinal anesthesia in cesarean section.
ABSTRACT
OBJECTIVE:To discuss the association between ABCB1 gene polymorphisms and adriamycin and cyclophospha-mide(AC)combined with chemotherapy-induced severe neutropenia in patients with breast cancer. METHODS:218 breast cancer patients receiving AC combined with chemotherapy were selected from our hospital during 2012-2015;PCR-RFLP was used to de-tect polymorphisms of ABCB1 2677G>T/A and 3435C>T. The associated between different age,BMI,clinical stages genotypes, etc and AC combined with chemotherapy-induced severe neutropenia were investigated,and risk factors of neutropenia were ana-lyzed by multivariate logistic regression. RESULTS:Among 218 breast cancer patients,170 patients suffered from severe neutrope-nia,accounting for 78.0%. Among ABCB1 2677G>T/A polymorphisms,distribution frequency of GT or GA genotype,TT,TA or AA genotype,GG genotype in severe neutropenia were 80.6%,86.2% and 60.0%,with statistical significance (PT polymorphisms,distribution frequency of TT,CT and CC genotype in severe neutropenia were 86.4%, 78.4% and 72.7%,there was no statistical significance(P>0.05). AST and ABCB1 2677G>T/A polymorphisms were correlated with severe neutropenia (PT/A polymorphism was a strong predictor of neutropenia [OR=3.875, 95%CI(1.555,9.922),P=0.008]. CONCLUSIONS:ABCB1 2677>T/A polymorphisms may be aggravate AC combined with che-motherapy-induced neutropenia in patients with breast cancer.