Detecting Hypercoagulability in Morbidly Obese and Non Obese Parturients Following Cesarean Section Delivery
Condition: Pregnancy; Obesity; Hypercoagulability
MeSH terms: Thrombophilia
Study type: Observational

Summary: 
      Investigators hypothesized that the impact of surgery in terms of inducing a hypercoagulable
      state is more evident in morbidly obese pregnant women as opposed to their non-obese
      counterparts. The aim of this study is to investigate the change in coagulation status of
      morbidly obese and non-obese pregnant women following cesarean section delivery using
      thromboelastometry. This observational study would also make it possible to calculate the
      sample size for a future prospective controlled clinical trial to compare the incidence of
      Hypercoagulability in morbidly obese parturients as opposed to their non-obese counterparts.
      To the best of our knowledge, no other work has been done any in this area.
    

Detailed description: 
      Following institutional ethical committee approval, 20 morbidly obese (BMI>40) and 20
      non-obese (BMI < 30) parturients undergoing elective low segment cesarean section (LSCS)
      delivery under spinal subarachnoid block will be recruited into the study. A written informed
      consent will be obtained from all parturients prior to inclusion. All patients will receive
      an information sheet at the preoperative assessment visit to inform them about this study.
      Patients with a history of past or current thromboembolism will be excluded from the study as
      well as those with liver disease and those already on anticoagulant/anti-platelet therapy for
      repeated miscarriage or other indications. History of thromboembolism is defined as an
      arterial or deep venous thrombosis, catheter thrombosis, or pulmonary embolism diagnosed by
      ultrasound or spiral computed tomography (CT). Preoperative baseline full blood count and
      clotting profile will be done. Parturients with abnormal platelet count or coagulation
      results and those who will need conversion to general anesthesia will be excluded.

      Data and sample collection Preoperative BMI, co-existing morbidities and laboratory test
      results including INR, PTT and platelet count as well as operative time and postoperative
      clinical or radiological evidence of thromboembolism will be recorded. A blood sample will be
      collected for ROTEM analysis prior to establishing the block (baseline), immediately after
      surgery and 8 hours later.

      ROTEM analysis

      Coagulability will be assessed using the ROTEM thromboelastometry analyzer (The ROTEM® delta,
      Tem Systems Inc.®, Munich, Germany). Extrinsic rotational thromboelastometry (EXTEM),
      intrinsic rotational thromboelastometry (INTEM) and FIBTEM will be measured for each blood
      sample. Clotting time (CT), clot formation time (CFT) and maximum clot firmness (MCF) will be
      recorded. Total clot strength will be assessed by "G" value as calculated according to the
      formula: (5000xMCF)/100-MCF and expressed as dynes/cm2 . G has been shown to be valuable in
      diagnosing hypo- and hypercoagulability . In non-obstetric cohorts, hypercoagulability was
      defined as a G value of ≥ 11.7 dynes/cm2 and hypocoagulability as a G value of <5.0 dynes/cm2
      (values provided by manufacturer).
    

Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Term pregnant women presenting for elective cesarean section under spinal anaesthesia
      
Keywords: Thromboelastometry; pregnancy; obesity