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What is Which of the following fits into the criteria of severe variable deceleration, variation less than _____________ and explain in detail?
Severe variable decelerations are defined as: Less than 70 beats/minute lasting at least 60 seconds. Variable deceleration is the abrupt decrease in FHR below the baseline. The decrease is 15 beats/minute or more, with a duration of 15 seconds or more but less than 2 minutes. Mechanism: Umbilical cord compression, leads to occlusion of the umbilical vein, hence there is decreased venous return to maintain cardiac cord. Classification: Mild: More than 80bpm irrespective of duration/less than 30 seconds irrespective of HR/70-80 bpm lasting 60 seconds Moderate: More than 70 bpm lasting 30-60 seconds/70-80 bpm lasting more than 60 seconds Severe: Less than 70 bpm lasting at least 60 seconds Ref: Nelson textbook of pediatrics 21st edition PGno: 884