Biomedical subjects

C J Shanley

Publications and source records attributed to C J Shanley.

23 records · Page 2Linked to original sources

PubMed1992

Early experience with adult extracorporeal membrane oxygenation in the modern era.

In 1980 we stopped using extracorporeal membrane oxygenation for adults because only 1 of 20 patients treated between 1973 and 1979 survived. In October 1988 we returned to adult extracorporeal life support (ECLS) with a modified protocol including venovenous access when possible, large oxygenators for CO2 clearance, activated clotting time of 180 to 200 seconds, and case selection based on 90% mortality (30% transpulmonary shunt). Of 19 patients referred, 14 met criteria for ECLS. Three of these 14 patients with isolated respiratory failure died before ECLS could be started, and 1 patient refused ECLS and died. Ten were placed on ECLS for 2 to 24 days. Indications were pneumonia (3), post-cardiac operation (2), and adult respiratory distress syndrome (5). Five recovered and 5 died. The cause of early death was progressive pulmonary injury (3), hemorrhage (1), and ventricular arrhythmia (1). One late death occurred at 3 months secondary to intraabdominal complications related to liver transplantation. In conclusion, 10 adult patients with severe respiratory failure were treated with extracorporeal life support; 5 patients recovered lung function and 4 of these patients survived and were discharged to home. Surviving patients were typically younger and were placed on ECLS early in their disease process, emphasizing that early intervention is one key factor to a successful outcome.

Adolescent↗

PubMed1992

Local production of interleukin-8 is associated with nosocomial pneumonia.

One hundred five (70%) of 151 patients hospitalized in the intensive care unit and undergoing mechanical ventilation had bronchial secretions that tested positive for interleukin-8 within 36 hours of admission. Arterial blood, mixed venous blood, and urine collected simultaneously all tested negative, except for 11 patients admitted with intra-abdominal septic foci. The presence of interleukin-8 in the pulmonary air space early in the course of hospitalization was significantly associated with patients with multiple injuries, the need for greater ventilatory support, the occurrence of pulmonary dysfunction, and a 66% incidence of nosocomial bacterial pneumonia. We conclude that the early local production of interleukin-8 in the lungs is an early marker of pulmonary injury and may be involved in the pathogenesis of nosocomial bacterial pneumonia.

Adult↗

PubMed1987

Hypertension during extracorporeal membrane oxygenation: cause, effect, and management.

The major complication of extracorporeal membrane oxygenation (ECMO) for the treatment of neonatal respiratory failure is bleeding related to heparinization. Systolic hypertension has emerged as another serious side effect in our experience. Thirty-eight of the first 41 newborns we treated with ECMO developed a systolic blood pressure greater than 90 mm Hg. The mean hypertension index (HI blood = hours greater than 90/hr on ECMO) was 0.17 +/- 0.16. Possible biochemical mediators were assayed in 17 patients. Plasma renin activity (PRA), aldosterone, epinephrine, norepinephrine, prostaglandin E2, thromboxane, and antidiuretic hormone were elevated. Angiotensin-converting enzyme (ACE) and prostacyclin were not elevated. Eighteen patients (44%) had intracranial hemorrhage (ICH), and 11 patients (27%) had clinically significant ICH. The HI was significantly (p less than 0.005) lower in those patients without ICH (0.11 +/- 0.01) than in those patients with ICH (0.25 +/- 0.04). PRA at hour 12, day 2, and day 3 was significantly higher (p less than 0.05) in patients experiencing ICH (62 +/- 42; 93 +/- 15; 73 +/- 30 ng/ml/hr) than in those without ICH (27 +/- 25; 14 +/- 8; 12 +/- 4 ng/ml/hr). An aggressive approach to medical management evolved that included hydralazine, nitroglycerine, and captopril, which protected against ICH. Two of 23 patients (9%) treated with the protocol sufferred clinically significant ICH, whereas nine of 18 patients (50%) treated before implementation of the protocol experienced ICH. The ACE inhibitor captopril was most effective in the control of hypertension. We conclude that systolic hypertension is common during neonatal ECMO, is associated with ICH, and is related to a high PRA. Aggressive management of hypertension during ECMO can reduce the incidence of ICH, and captopril is an important component of this aggressive medical management.

Aldosterone↗

PubMedDate not supplied

Plasma leakage through microporous membranes. Role of phospholipids.

Plasma leakage through microporous membrane oxygenators is a well known complication of prolonged extracorporeal circulation. The authors hypothesized that adsorption of bipolar plasma molecules, such as phospholipids on the microporous membrane, results in formation of a hydrophilic layer over the hydrophobic surface of the membrane; this, in turn, leads to plasma leakage at normal surface tensions. A lipid phosphorus assay was used to measure phospholipid adsorption onto the fibers of microporous membrane oxygenators tested under a variety of experimental conditions. Adsorption of phospholipids on the microporous membrane was concentration dependent. Reproducible plasma leakage occurred both in vitro and in vivo, and the time to leakage was dependent on the concentration of phospholipids adsorbed upon the microporous membrane. Based upon these results, the authors conclude that adsorption of phospholipids contributes to the development of plasma leakage through microporous membrane oxygenators.

Adsorption↗

PubMedDate not supplied

Prolonged extracorporeal circulation without heparin. Evaluation of the Medtronic Minimax oxygenator.

Bleeding remains the most common complication of prolonged extracorporeal life support (ECLS). This study evaluated the Medtronic Minimax (Annaheim, CA) microporous oxygenator with the Carmeda Bio Active (heparin bonded) Surface (Stockholm, Sweden) for use in prolonged neonatal ECLS. Eight adult sheep were maintained on venovenous extracorporeal circulation (ECC) for a period of 4 days without systemic heparin. After 4 days of venovenous ECC without anticoagulation, there was no evidence of significant bleeding, circuit thrombosis, or systemic embolism. Gas exchange, hydrodynamic performance, coagulation, and biocompatibility studies suggest that the Minimax is safe and reliable for short-term or long-term ECLS in neonates.

Animals↗