Clinical characteristics and sequelae of intrapartum hypertension – a retrospective cohort study

Abstract Background In a significant proportion of pregnant women, elevated blood pressure may first present during the intrapartum period. This phenomenon, intrapartum hypertension, is often overlooked as blood pressure during delivery is attributed to labour pain, analgesic agents and haemodynamic changes. Thus the true prevalence and clinical significance of intrapartum hypertension remains unknown. This study sought to define the prevalence of intrapartum hypertension in previously normotensive women, identify associated clinical characteristics, and its impact on maternal and fetal outcomes. Methods In this single-center retrospective cohort study, all available partograms were reviewed over a 1-month period at an outer metropolitan hospital in Sydney (Campbelltown Hospital). Women with diagnosed hypertensive disorders of pregnancy during the incident pregnancy were excluded. A total of 229 deliveries were included in the final analysis. Intrapatum hypertension (IH) was defined as two or more systolic blood pressure (SBP)⩾140 mmHg or diastolic blood pressure (DBP)⩾90 mmHg during the intrapartum. Demographic data at the time of the first antenatal visit for the incident pregnancy as well as final maternal outcomes (intrapartum and post-partum) and fetal outcomes were collected. Statistical analyses were carried out using SPSSv27 with adjustments for baseline variables. Results Amongst 229 deliveries, 32 women (14%) had intrapartum hypertension. Older maternal age (p = 0.02), higher body mass index (p < 0.01) and higher diastolic blood pressure at the first antenatal visit (p = 0.03) were associated with intrapartum hypertension. A longer second stage of labour (p = 0.03), intrapartum non-steroidal anti-inflammatory medications (p < 0.01) and epidural anaesthesia (p = 0.03) were associated with intrapartum hypertension, while IV syntocin for labour induction was not. Women with intrapartum hypertension had a longer inpatient admission following delivery (p < 0.01), and elevated postpartum BP (p = 0.02) with discharge on antihypertensive medications (p < 0.01). Intrapartum hypertension was not associated with poor fetal outcomes, though subgroup analyses showed that women who had at least a single elevated blood pressure reading during the intrapartum experienced poorer fetal outcomes. Conclusion In previously normotensive women, 14% developed intrapartum hypertension during delivery. This was associated with postpartum hypertension, longer maternal admission and discharge with antihypertensive medications. There was no difference in fetal outcomes.

## 摘要
### 背景
在相当比例的孕妇中，血压升高可能首次出现于产时（intrapartum period）。这一现象即产时高血压（intrapartum hypertension）常被忽视，因为分娩时的血压升高常被归因于分娩疼痛、镇痛药物及血流动力学变化。因此，产时高血压的真实患病率与临床意义至今尚不明确。本研究旨在明确既往血压正常的孕妇中产时高血压的患病率，识别其相关临床特征，并探讨其对母儿结局的影响。
### 研究方法
本研究为单中心回顾性队列研究，对悉尼远郊大都会医院（坎贝尔敦医院，Campbelltown Hospital）1个月内留存的所有产程图进行回顾分析。排除本次妊娠期间已确诊妊娠期高血压疾病的孕妇，最终共纳入229例分娩病例进行分析。产时高血压（intrapartum hypertension, IH）定义为产时两次及以上收缩压（systolic blood pressure, SBP）≥140 mmHg或舒张压（diastolic blood pressure, DBP）≥90 mmHg。收集本次妊娠首次产前检查时的人口统计学资料，以及最终的母亲结局（产时及产后）与胎儿结局。采用SPSS 27版进行统计学分析，并对基线变量进行校正。
### 研究结果
229例分娩病例中，32例（14%）发生产时高血压。产妇年龄较高（p=0.02）、体重指数更大（p<0.01）及首次产前检查时舒张压更高（p=0.03）与产时高血压显著相关。第二产程时长更长（p=0.03）、产时使用非甾体类抗炎药物（p<0.01）及硬膜外麻醉（p=0.03）与产时高血压相关，而静脉使用缩宫素引产与产时高血压无显著关联。合并产时高血压的产妇分娩后住院时间更长（p<0.01）、产后血压升高（p=0.02），且出院时需服用降压药物（p<0.01）。产时高血压整体与不良胎儿结局无显著关联，但亚组分析显示，产时至少出现一次血压升高的孕妇，其胎儿结局更差。
### 研究结论
既往血压正常的孕妇中，14%在分娩过程中发生产时高血压。该现象与产后高血压、产妇住院时间延长及出院时需服用降压药物相关，而胎儿结局无显著差异。