Effects of Sternal Wall Pressure in Children
Condition: Respiration, Artificial
Study type: Observational

Summary: 
      This protocol is a prospective, pilot, observational study in the Pediatric Intensive Care
      Unit (PICU), Progressive Care Unit (PCU) and the Operating Room (OR) settings at the
      Children's Hospital of Philadelphia (CHOP). We propose to observe, measure and report the
      effect of incremental gentle sternal pressure increases on intrathoracic pressure, and other
      surrogates of hemodynamic function, in stable mechanically ventilated children. This study
      will provide preliminary data to inform the resuscitation research community and assist
      development of evidence-based pediatric resuscitation guidelines in the future.
    

Detailed description: 
      Context: Survival outcome following cardiac arrest in children is poor, and recent evidence
      suggests that the quality of Cardiopulmonary Resuscitation(CPR) is critically important.
      Venous blood return to the thorax to refill the heart is essential for good quality CPR and
      critical organ perfusion. Adult cardiac arrest studies suggest that incomplete chest wall
      decompression (i.e. "leaning" on the sternum of the chest) during CPR affects intrathoracic
      pressure and impedes venous return. The consequence of "leaning" on the chest during CPR is
      increased intrathoracic pressure, which creates a "back-pressure" preventing optimal return
      of blood to the heart. The critical importance of manipulating positive and negative
      intrathoracic pressures during Cardiopulmonary Resuscitation (CPR) has been recently
      demonstrated in both animal and human studies. Food and Drug Administration (FDA) approved
      defibrillators with a force and depth sensor can monitor the depth, rate and complete release
      of sternal pressure during CPR. These FDA approved defibrillators have been introduced and
      implemented in the Pediatric Intensive Care Unit (PICU) at the Children's Hospital of
      Philadelphia (CHOP). These defibrillators can provide feedback on the force and amount of
      "leaning", but there is no data on the minimal amount of sternal pressure (or "leaning
      pressure") that affects intrathoracic or intravascular pressures or venous return to the
      heart. In addition, there is no data on how much force on the sternal pressure sensor (e.g.
      leaning on the sensor) begins to affect intrathoracic pressure in children. We propose to
      observe, measure and report the effect of incremental gentle sternal pressure increases on
      intrathoracic pressure, and other surrogates of hemodynamic function, in stable but
      critically ill and mechanically ventilated children. This study will provide preliminary data
      to inform the resuscitation research community and assist development of evidence-based
      pediatric resuscitation guidelines in the future.

      Objectives: 1) To characterize the effect of gentle, incremental increases in sternal chest
      pressure on intrathoracic pressure in mechanically ventilated children. 2) To characterize
      the effect of gentle, incremental increases in sternal pressure on regional perfusion
      pressures, when existing catheters (arterial, central venous, intracranial) are present.

      Study Design/Setting/Participants: This protocol is a prospective, pilot, observational study
      in the Pediatric Intensive Care Unit (PICU), Progressive Care Unit (PCU) and the Operating
      Room (OR)settings at the Children's Hospital of Philadelphia. The participants are a
      convenience sample of stable mechanically ventilated children from 6 months to < 8 years of
      age. A total of 20 patients will be enrolled, including a minimum of 10 with vascular
      catheters.

      Study Measures: The primary outcome variable is the change in intrathoracic pressure with
      incremental increase in gentle sternal pressure, measured by the peak airway pressure
      detected at the proximal end of the tracheal tube during end inspiration. Secondary outcomes
      include additional measures of intrathoracic pressure (end inspiratory pressure, mean
      pressure, area under the curve over 15 seconds, plateau pressure). For patients with
      indwelling central venous, arterial or intracranial pressure monitors, perfusion pressure
      changes will also be analyzed.
    

Observational model: Case-Only
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Any patient in the Pediatric Intensive Care Unit (PICU), Progressive Care Unit (PCU) and
        Operating Room (OR) settings involving stable, mechanically ventilated children in the
        Children's Hospital of Philadelphia.
      
Keywords: leaning; CPR; sternal pressure; incomplete release; chest compressions; pediatric