code: function Pulse(pw, iv, drip) {
      var pulse = this;
      plet.merge(pulse, drip.pulse);
      pulse.count = drip.cbCount + 1;
      pulse.event = drip.pulse.event;
  }
docs: Pulse event passed to listeners
  
  @private
  @class Pulse
  @arg {PulseEmitter} pw the pulse emitter
  @arg {Array} iv the I.V. catheter
  @arg {Object} drip the drip