Case Study: Type 1 Spinal Muscular Atrophy

 

Infants with Spinal Muscular Atrophy (SMA) develop respiratory insufficiency due to progressive respiratory muscle weakness caused by degeneration of alpha motor neurons in the spinal cord. This weakness results in ineffective airway clearance (obstruction), which is the major cause of morbidity and mortality in infants with SMA.  Thus, measurement of longitudinal changes in respiratory muscle function in infants and young children with SMA-1 is critical to the evaluation of interventions targeting SMA-1.

Accurate measurement of obstructive breathing can be obtained by examining the degree of asynchrony between abdominal and rib cage breathing. In this case study, VivoSense provided accurate and objective respiratory assessment services for a large multi-center clinical trial for a SMA-1 therapeutic. Infants were instrumented with Respiratory Inductance Plethysmography (RIP) sensors using the BioRadio. Appropriate breaths are selected using Kono-Mead plots (upper chart), phase relation between the breathing compartments (bottom chart), and abdominal and rib cage breathing movements (middle chart).

Case Study: RETT Syndrome

Rett syndrome (RTT) is a neurodevelopmental disease that results in neurological symptoms involving respiratory dysfunction. Breathing abnormalities are essential criteria for the diagnosis of RTT and include erratic respiratory rhythms and life threatening apneas. These respiratory symptoms are more severe during wakefulness than sleep.

In this case study, VivoSense provided objective, longitudinal respiratory assessment for a multi-center RTT clinical trial. Detailed respiratory waveforms were recorded using the BioRadio’s Respiratory Inductance Plethysmography (RIP) technology and were analyzed to score the frequency of periods of breathing dysregulation over time to objectively determine treatment efficacy.

Case Study: PTSD

 

UC San Diego researchers investigated whether reduced heart rate variability (HRV) before combat deployment conferred increased risk of a PTSD diagnosis after deployment. HRV from 1500 Marines were measured before combat deployment and again 4-6 months post deployment. The study found that U.S. Marines with reduced HRV prior to deployment displayed increased vulnerability to PTSD upon return, suggesting that a low HRV is a risk factor for developing PTSD.

The study recorded beat-to-beat heart rate using a fingertip PPG sensor and VivoSense provided a customized HRV analysis for the particular measurement protocol. HRV analysis importantly included suitable tools to manage the occurrence of confounding measurement artifact.

Case Study: Sedation

Respiratory insufficiency in post-operative patients following opioid analgesia is a common and life threatening problem. The efficacy of a candidate drug intended to increase minute ventilation by increasing tidal volume and secondarily through increasing respiratory rate (RR) was investigated in a clinical trial. Respiratory ventilation data were collected over several hours using Respiratory Inductance Plethysmography (RIP) using the Nox-T3 device. VivoSense provided custom routines for integration with sedation drug infusion and calibration against pneumotach data. Subjects were awake for several hours of monitoring, including periods of clinical assessments. VivoSense provided objective artifact management and assessments of key respiratory  outcome measures.