Influence of the Method of Alleviation of Aorto-Caval Compression on the Trans-Hepatic Ultrasound-Assessed Inferior Vena Cava Diameter In Pregnant Patients
Condition: Pregnancy; Cardiac Arrest
MeSH terms: Heart Arrest
Study type: Observational

Summary: 
      Cardiac arrest during pregnancy is rare but may result in poor maternal and fetal outcome.
      Because of its rare occurrence and ethical issues this topic is not very well studied and
      many questions pertaining to maternal resuscitation remain unanswered. One of the challenging
      aspects of cardiopulmonary resuscitation in a term pregnant patient is the ideal positioning
      during chest compressions. International societies have made recommendations regarding
      management of pregnant patients during cardiac arrest. They advocate the use of left lateral
      position with 30 degrees tilt or manual uterine displacement. However these recommendations
      are not based on high level of evidence. Ultrasound has been used to visualize the change in
      diameter of great vessels to determine the volume status or adequacy of blood circulation of
      these patients. This approach can be used to study the adequacy of blood circulation of
      pregnant patients in different positions. The objective of this study is to compare the
      change in Inferior vena cava diameter obtained with pregnant women in either the left lateral
      tilt or in the supine position with a manual uterine displacement, compared to the left
      lateral position and the supine position.

      Our hypothesis is that the inferior vena cava diameter obtained in the supine position with
      manual left uterine displacement would be larger as compared to that obtained with women
      positioned with a 30-degree tilt.
    

Detailed description: 
      Using the non-invasive technology of ultrasound we will be able to determine the degree of
      aorto-caval compression in pregnant women placed in different positions. The results of this
      study will help us to determine the optimal patient positioning for each individual. This in
      future may help us in improving outcomes not only during labor and anesthesia, but also
      during maternal resuscitation in critical cases.

      The results of this study will help us to determine the best technique to minimize
      aorto-caval compression in the term pregnant patient. The results of this study will be
      useful to establish firm maternal resuscitation guidelines. We will be able to determine the
      optimal maternal position during cardiopulmonary resuscitation and this may improve both
      maternal and fetal resuscitation outcomes.
    

Intervention name(s): Ultrasound
Intervention type(s): Device
Intervention description(s): The IVC will be visualized and images obtained using the intercostal window in both longitudinal and transverse planes.
Observational model: Case-Only
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Non-laboring, term prengnant women with singleton pregnancies who are admitted at Mount
        Sinai Hospital for induction of labor, elective cesarean section or for observation for any
        medical reason.
      
Keywords: Cardiopulmonary Resuscitation; Pregnancy; Ultrasound; Inferior Vena Cava