Biomedical subjects

Dee Ann Griffin

Publications and source records attributed to Dee Ann Griffin.

4 recordsLinked to original sources

PubMed2005

Extracorporeal membrane oxygenation to cardiopulmonary bypass with a single circuit exposure.

Due to the short supply of donor organs available, many patients decompensate or die while waiting for transplantation. Options for mechanical support for infants and pediatrics with congenital heart disease are limited because of the patient's size and device availability. Extracorporeal membrane oxygenation (ECMO) is the most common means of cardiac and respiratory support for these patients. One of the many indications for ECMO use in cardiac patients is as a bridge to transplantation, with patients being transported to the operating room (OR) on ECMO support. Converting the ECMO circuit to an open cardiopulmonary bypass system in the OR minimizes the patient's exposure to new circuitry, decreases further donor exposures and provides continuous support for patients in cardiac and/or respiratory failure. In addition, the ability to use modified ultrafiltration post-bypass aids in reducing extracellular fluid, increasing the hematocrit and improving hemodynamic stability following an extended duration of ECMO and bypass support. The integrity of the ECMO circuit is maintained and can be converted back to ECMO for support postoperatively if needed.

Cardiopulmonary Bypass↗

PubMed2003

Modified ultrafiltration postextracorporeal membrane oxygenation.

Modified ultrafiltration (MUF) has been widely used for the removal of extracellular water in the immediate postcardiopulmonary bypass (CPB) period. The reported benefits of this technique are improved hematological status and hemodynamic stability post-CPB, as well as a decrease in blood utilization during the operation. MUF has also been associated with improved pulmonary status along with enhanced myocardial performance. With these benefits in mind, we have explored the possible advantages of using MUF following extracorporeal membrane oxygenation (ECMO). The theoretical advantages of using MUF post-ECMO are the reduction of blood use prior to removal from ECMO for optimization of hemoglobin levels, improved pulmonary compliance decreasing the duration of ventilatory support, improved myocardial function, as well as the other reported benefits described with MUF post-CPB. This report communicates the technique used to perform MUF post-ECMO, as well as a simple MUF circuit design for use in the intensive care unit setting.

Cardiopulmonary Bypass↗

PubMed2002

Alleviating heat loss associated with modified ultrafiltration.

Modified ultrafiltration (MUF) has been described and utilized for the removal of extracellular water in the immediate postcardiopulmonary bypass (CPB) period. This technique has been associated with improved hematological status and hemodynamic stability post cardiopulmonary bypass. Hypothermia during the MUF period has been described as a complication associated with this technique. Decreased patient temperature may be associated with increased bleeding causing an increase in time to sternal re-approximation, OR time, decreases in cardiac function, peripheral vascular perfusion, and an increase in blood product utilization. These complications may reduce some of the benefits described with the use of MUF. The purpose of this study was to evaluate the use of a heated MUF infusion line to reduce the heat loss associated with this technique in a pediatric population. After obtaining Committee for Protection of Human Subjects exemption, a retrospective review to evaluate the efficiency of the hot MUF infusion line was undertaken. Twenty patients under 10 kg who underwent MUF before the change to a heated infusion line were retrospectively identified and matched to patients undergoing MUF with a heated infusion line with regard to weight, lesion, procedure, surgical staff and technique, and disposable equipment. Groups were evaluated for temperature and hematocrit change during the MUF period, blood loss and transfusion postprotamine in the OR and 24 h, and time to sternal re-approximation postprotamine. Statistical significance was seen between the two groups in temperature (-0.24 +/- 0.72 vs. - 1.58 +/- 0.89 degrees C; p < .0001) with the HotLine group having little change post MUF. Significance was also seen in the last OR temperature recorded (37.0 +/- 1.2 vs. 36.0 +/- 1.0 degrees C; p = .01) with the HotLine group having the higher temperature. There were no significant differences in hematocrit levels at 24 hours, last in the OR, or the change after the MUF period. No significant difference was found in blood transfused postprotamine in the OR, 24-h blood transfused, 24-h chest tube loss, or sternal closure. The study suggests that the use of a heated MUF infusion line safely reduces the heat loss associated with MUF in the immediate post-operative period.

Body Temperature Regulation↗

PubMedDate not supplied

Blood gas strategies and management during pediatric cardiopulmonary bypass.

Blood gas management during hypothermic cardiopulmonary bypass may be corrected by pH stat or alpha stat strategy. The pH stat philosophy is to maintain the blood pH constant at any temperature. Carbon dioxide must be introduced to the oxygenator in order to maintain the pH and pCO2 during hypothermic cardiopulmonary bypass. Conversely, during alpha stat blood gas management pH is maintained according to 37 degrees C despite the patient temperature. Alpha stat management preserves intracellular pH and autoregulation of cerebral vasculature by following the natural shift of the oxyhemoglobin dissociation curve. In-line blood gas analysis is a practical tool in assessing adequate blood gas management, because this technology provides immediate detection for modification of air/oxygen/carbon dioxide parameters. Results from several studies favor the pH stat strategy during neonatal cardiopulmonary bypass. This strategy increases tissue oxygenation and cerebral blood flow while cooling. Data also suggest that pH stat management results in better outcomes with shorter ventilation times and intensive care unit stays after pediatric cardiac surgery.

Blood Gas Analysis↗