2005 OPEN FORUM Abstracts
NEW AND NOVEL PULSE OXIMETRY IN PATIENTS WITH SEVERLY INJURED SKIN
Rodney Plapp, RRT; Travis Collins, BS, RRT; Kevin Marino, RRT; Thomas J. Cahill, RRT; John McCall, MD; Richard Kagan, MD Shriners Hospital for Children, Cincinnati, Ohio
Introduction: We tested a reflectance pulse oximeter (PRO2) from ConMed Corporation (Utica, NY, USA). The distinctive sensor design (3 low output central light sources encircled by 2 detector rings), allows for sensing from a flat skin surface. In addition to SpO2 and pulse rate, the unit displays %PA (relative pulse amplitude). The sensor is held to the skin by an adhesive-based holder that maintains the sensor against the skin and provides optical shielding. Potential advantages in burn care include: use of central body sites, sensitivity in low perfusion, monitoring local signal strength, and reduced risk of adhesive and thermal injury.
CASE 1: A 13-month-old female had a 36% total body surface area (TBSA) grease scald burn. ARDS required high settings on the Volume Diffusive Respirator (VDR®), inhaled Nitric Oxide to assist with oxygenation (P/F= 51), and use of high dose vasopressors to maintain blood pressure.
CASE 2: A 20-month-old male developed Meningococcus Meningitis that worsened with Purpura Fulminans, resulting in dry gangrene of both lower legs as well as both hands. Treatment involved bilateral below the knee amputations and amputation of both hands. Pulse oximetry was needed for his intraoperative and postoperative care.
CASE 3: A 5-year-old male had a 90% TBSA gasoline flame burn. ARDS required high settings on the VDR, an open laporotomy due to high intra-abdominal pressures and tracheostomy. Due to the large surface area burn the team had difficulty maintaining his core temperature.
CASE 1: ARDS and the use of vasopressors so challenged this child that the transmission-based oximeter was not consistently displaying data. The PRO2 sensor was placed on the forehead and provided a consistent signal, allowing titration of care during critical phases of the ICU stay.
CASE 2: With amputations of the hands and feet, the choice of a transmission-type pulse oximeter sensor site was limited to the patient's ear lobe. The result was a weak signal, a sensor that often slipped off and a sensor that required frequent adjustment to prevent tissue breakdown. The PRO2 SpO2 data from the back and forehead was closer (96 versus 100) to the arterial blood gas (97).
CASE 3: Hypothermia and the large TBSA limited the transmission sensor site to the ear. The result was a weak signal, a sensor that often slipped off and a sensor that required frequent adjustment to prevent tissue breakdown. Use of the PRO2 sensor on the forehead gave us more consistent readings without the need to move the sensor. These reading mimicked the arterial blood gases closer than a transmission-type oximeter.
Conclusion: A PRO2 pulse reflectance oximeter was tested without adverse effects on three patients with a wide range of pathology and where monitoring with a transmission-type pulse oximeter was problematic. Central positioning of the reflectance sensor was very helpful, particularly in those with low arterial pressure. A benefit of more reliable and consistent monitoring is that it may allow more rapid identification and treatment of oxygenation and poor pulse amplitude at the sensor site. The monitoring of %PA could prove helpful in alerting caregivers a condition of pulses so small as to compromise the health of grafted tissue or flap closure. The benign sensor holder and low contact temperature should allow placement for periods much longer than other pulse oximeter sensors thereby maintaining skin integrity and reducing caregiver workload. As a result, the PRO2 System should expand the variety of pulse oximetry uses, while having less risk.