Extracorporeal membrane oxygenation ECMO

Other specialized appHcations of cardiac arrest devices include extracorporeal membrane oxygenation (ECMO) which occurs when the lungs of a premature infant caimot function properly. The market segments for cardiopulmonary support devices are potentially significant. 

Hart L, Cobaugh D, Sean B, et al. 1991. Successful use of extracorporeal membrane oxygenation ecmo in the treatment of refractory respiratory failure secondary to hydrocarbon. Vet Hum Toxicol 33(4) 361. 

Children-The recommended dose in pediatric patients is for a total daily dose of 2 to 4 mg/kg, to be divided and administered every 6 to 8 hours up to a maximum of 50 mg given every 6 to 8 hours. Limited data in neonatal patients (under 1 month of age) receiving extracorporeal-membrane oxygenation (ECMO) have shown that a dose of 2 mg/kg is usually sufficient to increase gastric pH to greater than 4 for at least 15 hours. Therefore, consider doses of 2 mg/kg given every 12 to 24 hours or as a continuous infusion. 

Serum samples and autopsy specimens were examined from two infants with congenital diaphragmatic hernia who had received life support with extracorporeal membrane oxygenation (ECMO). The serum levels of di(2-ethylhexyl) phthalate after 14 and 24 days of ECMO support were 26.8 and 33.5 mg/L respectively, and levels of 3.5, 1.0 and 0.4 mg/kg di(2-ethylhexyl) phthalate were found in liver, heart and testicular tissues, respectively, and trace quantities were found in the brain. The rate of di(2-ethylhexyl) phthalate extraction from the model PVC circuits was linear with time (rate, 3.5 and 4.1 mg/L per hour). The exposure to di(2-ethylhexyl) phthalate for a 4-kg infant on ECMO support for 3-10 days was estimated to be 42-140 mg/kg (Shneider et al., 1989). 

The toxicity of di(2-ethylhexyl) phthalate was evaluated in 28 term infants with respiratory failure, 18 of whom received extracorporeal membrane oxygenation (ECMO) and were compared with 10 untreated infants. Various clinical parameters of liver, pulmonary and cardiac dysfunction were found to be unaffected in treated infants, even though the rate of administration ranged up to 2 mg/kg bw di(2-ethylhexyl) phthalate over 3-10 days (mean peak plasma concentration, 8 pg/mL). ECMO is considered to be the clinical intervention that results in the highest intravenous dose of di(2-ethylhexyl) phthalate (Karle et al., 1997). 

All of the above-mentioned blood oxygenators are used outside the body, and hence are referred to as extracorporeal oxygenators. They are mainly used for heart surgery, which can last for up to several hours. However, blood oxygenators are occasionally used extracorporeally to assist the pulmonary function of the patients in acute respiratory failure (ARF) for extended periods of up to a few weeks. This use of extracorporeal oxygenators is known as extracorporeal membrane oxygenation (ECMO). 

Exposures of neonatal children to DEHP can be especially high as a result of some medical procedures. For example, upper-bound doses of DEHP have been estimated to be as high as 2.5 mg/kg/day during total parenteral nutrition (TPN) administration and 14 mg/kg/day during extracorporeal membrane oxygenation (ECMO) procedures. 

Figure 9 Degree of platelet retention in unheparinized rabbits undergoing simulated extracorporeal membrane oxygenation (ECMO) whose extracorporeal blood conduits are lined with MAHMA/NO-containing PVC to inhibit platelet adhesion ( ) as compared with controls whose tubing is made of undiazeniumdiolated PVC ( ). [Adapted from Reference 13 with permission.]...

Recently, treatment options for RDS have advanced significantly. Effective drug therapies include surfactant and perfluorocarbons (PECs). Nitric oxide and extracorporeal membrane oxygenation (ECMO) have been used as final resorts. Supportive therapies such as mechanical ventilation, management of acidosis, and diuresis are also important. An algorithm for prevention and treatment of neonatal RDS is presented in Fig. 28-2. 

In pediatric patients with ARDS, extracorporeal membrane oxygenation (ECMO) has been used." These patients have been part of larger cohorts identified as respiratory failure. Anecdotally, practitioners observe the greatest benefit in the sickest patients. Prospective studies are needed to confirm clinical impression. The benefits of ECMO for adults with ARDS seem less optimistic." ... 

Cardiopulmonary bypass—The use of extracorporeal devices to pump blood and oxygenate the blood while the heart or lungs are not functional. Extracorporeal membrane oxygenation (ECMO) is a form of long-term cardiopulmonary b5 pass that is typically used for days to weeks. 

The hopes for the use of Extracorporeal Membrane Oxygenation (ECMO) for treating acute respiratory failure went through a low point in the mid 1970 s after the results of the National Insti-... 

With ECMO, it s always an intense time, always a complex patient," states the medical director of an extracorporeal membrane oxygenation (ECMO) program in a busy neonatal intensive care unit. 

Sometimes extracorporeal membrane oxygenation (ECMO) or cardiopulmonary bypass is required, especially in patients with pulmonary hypertension, to protect the pulmonary circulation and the left ventricle from volume overload. After single-lung TX double-lumen tracheal tubes are sometimes used to ventilate both lungs separately for some hours to avoid hyperinflation of the native emphysematous lung. 

Besides common direct measurements, indirect methods for blood gas determination are as follows capnometry (only PCO2), transcutaneous blood gas measurement [1, 4], and the pCOa [5] and p02 [6] determination at the gas outlet of a membrane oxygenator during extracorporeal membrane oxygenation (ECMO). However, these methods cannot replace the invasive blood gas analysis because of a number of limitations and the risk of artifacts. Typical problems are the patients disease pattern, age, the entire health condition, etc [4,7,8]. Nevertheless, these noninvasive alternatives for the monitoring of arterial blood gases have been applied, e.g., during cardiopulmonary bypass [5]. 

Fig. 3 Scheme of an extracorporeal membrane oxygenation (ECMO) combining a membrane oxygenator and a centrifugal pump. Oxygen diffuses into the blood (oxygenation) and carbon dioxide diffuses out of the blood (CO2 elimination)... 

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