Factors influencing brain natriuretic peptide levels in healthy pregnant women

BACKGROUND

The normal range of plasma brain natriuretic peptide (BNP) in pregnant women is still unclear. Moreover, pregnant women experience dynamic body weight changes and suffer from anemia, but effects on maternal BNP have not been investigated. This study aimed to reveal the normal plasma BNP range and examine the effects of physiological changes on BNP among pregnant women.

METHODS AND RESULTS

Plasma BNP, hemoglobin, plasma creatinine and BMI were measured in 58 non-pregnant control women and in 773 normal pregnant women at late pregnancy, early postpartum and 1-month postpartum. Mean plasma BNP (in pg/mL) was 11.8 (95% confidence interval: 0-27.5) in non-pregnant women, 17.9 (0-44.7, p<0.001) at late pregnancy, 42.5 (0-112.6, p<0.001) early postpartum and 16.1 (0-43.9, p=0.001) 1-month postpartum. Multiple regression analysis revealed that pre-delivery BNP levels were negatively correlated with BMI (p<0.001) and hemoglobin (p=0.002) and positively correlated with creatinine (p<0.001). Post-delivery BNP was positively associated with body weight change during pregnancy (p=0.001) and post-delivery creatinine (p=0.010) but negatively associated with body weight loss at delivery (p<0.001) and post-delivery hemoglobin (p=0.004).

CONCLUSION

Even normal pregnancy affects plasma BNP, particularly in the early postpartum period, indicative of cardiac stress. Plasma BNP levels are affected by BMI, body weight changes, creatinine and hemoglobin levels; therefore, these factors should be considered when analysing cardiac function and the physiological implications of BNP levels in pregnant women.

Intra-aortic balloon pump in coronary artery bypass graft - factors affecting outcome

BACKGROUND

The management of coronary artery bypass graft (CABG) patients, especially in high risk patients ,can be challenging as the postoperative periods may be characterized by a low cardiac output state. Inotropes used in the perioperative periods to increase cardiac output may be detrimental thus making the use of mechanical devices like intra-aortic Balloon pump (IABP) for circulatory assistance desirable.

AIMS & OBJECTIVES

To study the use of intra-aortic balloon pump in coronary artery bypass patients in preoperative and post operative settings and factors that affect morbidity and mortality.

SETTING

Madras Medical Mission, Chennai, India.

METHOD

A retrospective study of 3974 consecutive patients who had CABG done between March 2007 and February 2011 with or without additional procedures. One hundred and seven (2.7%) patients had IABP instituted either pre-operatively or postoperatively when it was obvious the patient will need cardiac assistance. The demographic data, clinical features, the indications for insertion, management offered and outcome , the creatinine levels, the duration of intraarortic balloon pump, the intensive care unit(ICU) and Hospital stay were analyzed for means and standard deviations and Pearsons Chi-square test using SPSS 10.0 window soft ware version with significant value of p-value<0.005.

RESULT

The mean age of all the patients was 59.7 + SD 10.7, 85(79.4%) patients were males,22(20.6%) were females .Out of the 107 patient who had IABP insertion, 59(55.1%) patients had IABP inserted preoperatively and 48(44.9%) postoperatively. The creatinine levels after the insertion of IABP in 68 patients was<1.5mg/dl and in 39 patients was>1.5mg/dl with mortality of 15.0% for the preoperative insertion group versus 29.0% for the postoperative group respectively (p=0.005). The preoperative and postoperative insertion ICU stay were 8.3+4.7 days and 5.7+1.6days respectively (p=0.005) and mortality were16.8% and 27.1 %( p=0.005) respectively.

CONCLUSION

Early institution of intra-aortic balloon pump gives a better outcome even in high risk coronary artery bypass graft patients as it reduces ICU stay and mortality, and elevated post-insertion creatinine levels has been shown to be an indicator of impending mortality and so an early warning for putting in place mitigating protocols.