Lateralization of brain lesions following extracorporeal membrane oxygenation.

The cranial ultrasound and computed tomography scan films of 180 patients who underwent extracorporeal membrane oxygenation were reviewed. Sixteen patients were considered to have moderate to severe brain lesions. Of these, 6 were ischemic and 10 were hemorrhagic. Five (83.3%) of the 6 ischemic lesions involved the right side and only 1 ischemic injury occurred on the left. Seven (70%) of the 10 hemorrhagic lesions occurred solely or predominantly on the side opposite the carotid ligation and 3 were found on the same side as the ligation. One patient suffered a right temporal hemorrhage following cannulation of the left common carotid artery. There was no predominance of brain lesions for either side when both hemorrhagic and ischemic lesions were combined. These observations implicate alterations in cerebrovascular hemodynamics accompanying carotid ligation and reperfusion in the pathogenesis of central nervous system lesions associated with the extracorporeal membrane oxygenation procedure. It is suggested that systematic classification of brain lesions associated with extracorporeal membrane oxygenation be made to get a better understanding of their pathology.

Extracorporeal membrane oxygenation selection criteria: partial pressure of arterial oxygen versus alveolar-arterial oxygen gradient.

Extracorporeal membrane oxygenation (ECMO) has dramatically increased the survival rate of hypoxemic neonates who are unresponsive to maximum conventional medical therapy. Because ECMO involves multiple risks, including ligation of the right common carotid artery and right internal jugular vein, ECMO candidates should be neurologically intact neonates with a high probability of death despite maximum conventional ventilatory support. Currently, criteria based on the calculated alveolar-arterial oxygen gradient (A-aDO2) have replaced the neonatal pulmonary insufficiency index for predicting mortality and, thus, ECMO eligibility. A retrospective review of death prediction for the 26 months prior to the initiation of an ECMO program revealed a sensitivity of 67% and a specificity of 96% using the criterion of a PaO2 of less than 50 mm Hg for four hours. An equivalent A-aDO2 criterion of greater than or equal to 630 for four hours produced a sensitivity of 61% and a specificity of 96%. Prediction of mortality in neonates with sepsis was poor regardless of the criteria used. Excluding the deaths due to sepsis increased the sensitivity to 86% and 79% using criteria based on PaO2 and A-aDO2, respectively. It is concluded that the use of criteria based on PaO2 is equivalent to criteria based on A-aDO2 for predicting mortality. Criteria based on PaO2 may, however, decrease both the false-negative rate (patients with an elevated PCO2) and the false-positive rate (patients with intentionally induced hypocarbia secondary to hyperventilation alkalosis).

Right atrial thrombus formation screening using two-dimensional echocardiograms in neonates with central venous catheters.

Two-dimensional echocardiograms were used to prospectively screen 49 patients with 56 central venous catheters for right atrial thromboses from October 1985 to May 1986. All but four patients received a two-dimensional echocardiogram prior to insertion of the catheter. Once the catheters were in place, two-dimensional echocardiograms were performed no later than 3 weeks after insertion and then every 14 days until the catheter was removed. A single thrombus was detected 79 days after catheter placement (an incidence of 1.8%). Previous recommendations for weekly screening with two-dimensional echocardiogram were based on case reports alone. The 95% confidence limits for a negative two-dimensional echocardiogram result suggest that the initial two-dimensional echocardiogram screen for thrombus be obtained no sooner than 3 weeks after catheter insertion. In addition, significant gastrointestinal disease requiring operative intervention was present in 10 of 11 previous case reports as well as in our patient. Further studies with larger sample sizes are needed to determine whether subgroups of infants exist who are at a relatively higher risk for right atrial thrombus formation.

Outbreak of amikacin-resistant Enterobacteriaceae in an intensive care nursery.

An outbreak of amikacin-resistant Enterobacteriaceae (KES) occurred in the Intensive Care Nursery (ICN) of the Louisville General Hospital from January 1978 through March 1978. Epidemic disease and an increased colonization rate in newborn infants due to amikacin-resistant microorganisms has not been documented previously. Three of the 11 neonates died. The organisms isolated were resistant to amikacin and two experimental aminoglycosides, sissomicin and netilmicin. The outbreak was contained following institution of several control measures, including pharyngeal inoculation of an experimental strain of alpha streptococcus in four infants.

Extracorporeal membrane oxygenation and early-onset group B streptococcal sepsis.

Recently, extracorporeal membrane oxygenation (ECMO) has been used as rescue therapy for newborns with overwhelming early-onset group B streptococcal sepsis. To determine which clinical factors best predict mortality and to evaluate the outcome of this therapy, a retrospective examination of the clinical course and outcome of ECMO-eligible newborns with early-onset group B streptococcal sepsis was undertaken. The study period was divided into two phases based on when ECMO was initially used at Kosair Children's Hospital as therapy for septic neonates. Phase 1 (pre-ECMO) was the period from January 1, 1982, through June 15, 1986, and phase 2 (ECMO) from June 16, 1986, through December 31, 1989. Newborns with gestational age greater than or equal to 34 weeks, birth weight greater than or equal to 2000 g, and evidence of early-onset group B streptococcal sepsis were eligible for study. Only newborns who received mechanical ventilation were evaluated. Sixteen patients from phase 1 met the above criteria. Of those, 10 exhibited no sign of hypotension and all survived. Of the 6 patients with hypotension, 3 died. Forty patients were identified from phase 2. Seven patients remained normotensive and all survived. Thirty-three patients were hypotensive, of which 15 received ECMO and 13 survived. Of the 18 who did not receive ECMO, 7 died. Regarding all hypotensive newborns, those who did not receive ECMO had a trend toward lower survival (P less than .06) and were more likely to die if they were of lower birth weight, manifested a persistent acidosis (pH less than or equal to 7.25), and had an absolute neutrophil count less than 500 cells/mm3.(ABSTRACT TRUNCATED AT 250 WORDS)

Nonhyperoxic retrolental fibroplasia.

Retrolental fibroplasia (RLF) has most often been observed in preterm infants exposed to high ambient oxygen concentrations. This case report describes an infant near term who was never exposed to supplemental oxygen but in whom stage 4 RLF developed. The etiologic role of exchange transfusion is discussed.

Infant orthotopic cardiac transplantation.

Infant orthotopic cardiac transplantation has been recently applied to various forms of congenital heart disease with encouraging short-term results. Between June 1986 and September 1987 we evaluated 16 infants for orthotopic cardiac transplantation. Fourteen had hypoplastic left heart syndrome, one had endocardial fibroelastosis with aortic atresia, and one had anomalous pulmonary arterial origin of the left main coronary. Eight families accepted the treatment program and eight families refused (two because of associated anomalies and six on philosophical grounds). Of the eight patients who were candidates for orthotopic cardiac transplantation, one died 6 hours after diagnosis, one was allowed to die after 60 days because of acquired neurologic complications, and another had congenital cytomegalic virus infection. The remaining five patients (four with hypoplastic left heart syndrome, one with anomalous pulmonary arterial origin of the left main coronary) had orthotopic cardiac transplantation. The operation was performed with absorbable polydioxanone suture with deep hypothermia and circulatory arrest in four neonates for hypoplastic left heart syndrome (average time 47 minutes) and bicaval cannulation and continuous bypass in one 11-month-old infant for anomalous origin of the left main coronary. In-house retrieval was used in all. One neonate died of complications as a result of pretransplant donor heart dysfunction and size discrepancy, whereas the remaining three neonates and one infant survived and are home 23 months, 12 months, and 8 months (the patients with hypoplastic left heart syndrome) and 17 months (the patient with anomalous origin of the left main coronary) postoperatively. Triple-drug immunosuppression included cyclosporine, azathioprine, and prednisone. Rejection was diagnosed by clinical evaluation of child activity and monocyte cell cycle analysis from peripheral blood samples without myocardial biopsies. Routine echocardiograms, electrocardiograms, and chest x-ray films were not helpful. Six episodes of rejection were successfully treated in four patients. Twelve-month postoperative catherization in one patient (hypoplastic left heart syndrome) showed appropriate graft growth, no aortic or pulmonary anastomotic strictures, normal right and left ventricular function, and no coronary artery disease. We conclude that infant orthotopic cardiac transplantation is an acceptable procedure for severe forms of untreatable congenital heart disease. The excellent short-term results warrant continued application of orthotopic cardiac transplantation.

Varicella exposure in a neonatal intensive care unit: case report and control measures.

Forty-six infants in a neonatal intensive care unit and 138 health care workers were exposed to a pediatric medical resident during the prodromal period and the early days of unrecognized varicella. An attempt was made to prevent an outbreak of additional cases by the institution of emergency control measures. These measures included rapid identification of varicella antibody status in exposed neonates, varicella antibody testing of health care workers with unknown or uncertain history of varicella, prompt administration of varicella zoster immune globulin to potentially susceptible persons, and cohorting neonates on the basis of exposure and antibody status. Passive maternal antibody was detected in 44 of the neonates. Of 27 health care workers who reported either a negative or an uncertain history of varicella, 26 had detectable antibody. No overt cases of varicella occurred in exposed patients or personnel.

Dyphylline elimination kinetics in lactating women: blood to milk transfer.

A population of 20 normal lactating females between the ages of 20 and 35 years was treated with a single 5 mg/kg intragluteal dose of dyphylline, 7-(2,3-dihydroxypropyl)theophylline. The distribution of the drug between blood and milk and its pharmacokinetics of elimination were determined. The apparent volume of distribution (Vd) of dyphylline was found to be 0.505 +/- 0.162 l./kg, the elimination rate constant (Kel) was 0.228 +/- 0.055 hr-1, the biological half-life (t1/2) was 3.21 +/- 0.76 hr, and the total body clearance (CI) was 0.109 +/- 0.036 l./kg/hr. The ratio described by dyphylline distribution between milk and serum (M/S) was 2.08 +/- 0.52. The elimination rate from milk was equivalent to that from blood.

Developmental sequelae in premature infants undergoing ligation of patent ductus arteriosus.

One hundred sixteen infants who underwent on-unit ligation of patent ductus arteriosus (PDA) were examined for developmental sequelae. Mean gestational age of the study group was 29.1 weeks; mean birth weight, 1,232 gm; and mean duration of follow-up, 20.7 months (chronological age). Seven infants died of severe bronchopulmonary dysplasia (4) and severe central nervous system dysfunction (3) before they were 3 years old. Sixty-five percent of the remaining infants exhibited normal motor and mental development, although 58% showed some degree of postnatal growth retardation. There was no evidence of left arm dysfunction caused by the thoracic incision; 3 infants had minor problems with nonabsorbed sutures at 3 to 6 months of age. No infant demonstrated recurrence of ductal patency. Mild sensorineural handicaps not expected to be of long-term importance were noted in 20 infants. Eighteen other infants (15.5%) were classified as having moderate to severe impairments, which may have substantial impact on development and ability to function. Surgical ligation of PDA in premature infants has been shown to be safe and effective in the short run. Long-term follow-up suggests that infants who undergo PDA ligation do not appear to be at increased risk for sensorineural handicaps.

Management of patent ductus arteriosus in the premature infant: indomethacin versus ligation.

A previous report from our institution analyzed the results of pharmacological (indomethacin) closure of patent ductus arteriosus (PDA) in 82 neonates. Closure was achieved in 54 patients. However, gastrointestinal complications occurred in 21, necrotizing enterocolitis in 13, and focal perforation in 8. Overall mortality in the indomethacin group was 40%. This paper compares the results of that pharmacological experience with our subsequent surgical experience with 86 low-birth-weight neonates for whom gestational age, size, illness, and mode of diagnosis were comparable. Mean weight at operation for this study was 1.1 kg; mean gestational age was 29.1 weeks. All infants required endotracheal-assisted ventilation for severe radiographic and clinical hyaline membrane disease. Range-gated Doppler study, retrograde flush aortography, and echocardiographic measurement of the ratio between the left atrium and the aortic root were used to confirm the diagnosis of PDA. Ligation was done in the neonatal intensive care unit using local anesthesia supplemented with morphine. Ventilation was controlled by an inhalation therapist; drug and blood administration were controlled by the infant's nurse. Surgical ligation was employed in all infants except for 7 in whom hemoclip ductal closure was chosen because of extreme instability, coagulopathy, or ductal perforation. There were no operative deaths. Surgical morbidity included ductal perforation (2 patients), wound infection (1), and phrenic nerve injury (1). Necrotizing enterocolitis occurred in 9 patients. The overall mortality was 17%. Patients with preoperative pneumo-thorax had a 32% overall mortality.(ABSTRACT TRUNCATED AT 250 WORDS)

Bilateral microphthalmos with colobomatous orbital cyst and de-novo balanced translocation t(3;5).

A term Caucasian male infant, born to a healthy non-related couple, was noted at birth to have bilateral edema and bluish discoloration of the lower eyelids. On physical examination, the eye globes were not visualized and hypertelorism was noted. Radiological imaging revealed large bilateral orbital cysts, microphthalmos, and severe optic nerve hypoplasia. Histological study of the excised orbital masses showed cysts lined by primitive, immature retinal tissue which contained neuroglial elements and scattered dysplastic rosettes. Chromosome analysis revealed an apparent balanced reciprocal translocation between the long arm of chromosome 3 and 5, i.e. 46, XY, t (3; 5) (q27; q11.2). Chromosome studies in parents were normal. To our knowledge, the association of this balanced translocation and microphthalmos with cyst has not been previously described in the English literature.

Acute effects of changing plasma osmolality and colloid oncotic pressure on the formation of brain edema after cryogenic injury.

The cerebral effects of alterations in plasma osmolality (Osm) and colloid oncotic pressure (COP) were examined in normocarbic, normothermic, pentobarbital-anesthetized rabbits that had been subjected to cryogenic brain injury. Monitored variables in all animals included mean arterial, right atrial, and intracranial pressures (MAP, CVP, and ICP), electroencephalographic (EEG) recordings, and cerebral blood flow (CBF). When surgical preparation was complete, a left parietal lesion was produced with liquid nitrogen. Group 1 (control, n = 8) animals subsequently received only maintenance fluids [lactated Ringer's solution (LR)]. One hour after injury, 3 other groups of animals underwent 45 minutes of plasmapheresis, carried out by arterial phlebotomy (packed red cells returned), with separated plasma being replaced by one of three fluids given in amounts sufficient to maintain MAP and CVP at baseline values. The three fluids were 1) 6% hetastarch in hypo-osmotic LR [Group 2 (Hypo-Osm), n = 6; COP = 21 mm Hg, Osm = 130 mOsm/kg]; 2) iso-osmotic LR [Group 3 (Hypo-COP), n = 8; COP = 0; Osm = 305]; and 3) 6% hetastarch in iso-osmotic LR [Group 4 (Iso-Osm/COP), n = 8; COP = 21, Osm = 310]. The animals were killed by exsanguination 25 minutes after completion of plasmapheresis. The brain was removed, the hemispheres separated, weighed, and sliced, and the specific gravities (SpGr) of the regional tissue determined. There were no differences in MAP, CVP, regional CBF, or EEG activity among the groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Use of extracorporeal life support in total anomalous pulmonary venous drainage.

OBJECTIVE: The objective of this study was to analyze the clinical course and neurodevelopmental outcome of infants with total anomalous pulmonary venous drainage (TAPVD) who were treated with venoarterial extracorporeal life support (ECLS). STUDY DESIGN: The study was done by retrospective national survey of ECLS centers located in the United States and Australia. Sixty-six patients from 28 centers that reported cases from 1976 to October 1992 to the Extracorporeal Life Support Organization registry were included in the study. Data regarding type of TAPVD, whether the diagnosis was known or suspected before the initiation of ECLS, method of diagnosis, timing of repair if done, outcome, and follow-up were collected. RESULTS: Fifty-six of the patients were placed on ECLS at ages < 14 days (neonatal) and 10 patients underwent ECLS at ages > or = 14 days (pediatric). TAPVD was known or suspected before the initiation of ECLS in 35 (53%) of 66 and was most commonly diagnosed by color-flow Doppler echocardiography if initially missed. Surgical repair was not attempted in four of the 66 patients, leaving a total of 62 patients for comparison. The overall operative survival for both neonatal and pediatric patients was 24 (39%) of 62. The survival rate for neonates who underwent repair before ECLS was seven (54%) of 13, for those who underwent repair after ECLS it was six (60%) of 10, and for those who underwent repair during ECLS survival was seven (24%) of 29. Neonatal survival (20/52, 38%) was statistically more likely (p = 0.05) if the repair was done before or after ECLS rather than during ECLS, with each group compared separately. Follow-up data were available on 13 of 20 neonates and three of four pediatric patients. Bayley Scales of Infant Development scores were normal in only six (54%) of 11 survivors who returned for testing. CONCLUSIONS: The diagnosis of TAPVD was often known before the initiation of ECLS. Neonates were more likely to survive if the repair could be done before or after ECLS rather than during ECLS. The lower survival of infants who underwent repair during ECLS reflects the degree of illness in many of these infants who were placed on ECLS on an emergency basis because their condition was too unstable to permit detailed cardiac evaluation. The survival rate of infants with TAPVD requiring ECLS is poor, with approximately one half of the survivors having mental and motor deficiencies; however, these infants represent a subset of patients with TAPVD who probably would have died without ECLS. We recommend that infants who are not starting to wean from ECLS at 7 days undergo reevaluation with color-flow Doppler echocardiography with consideration for cardiac catheterization if the diagnosis is in doubt. We also recommend that before infants with known TAPVD are placed on ECLS parents should be informed that survival with the use of ECLS is no different from survival with operation alone and that many of the survivors are impaired. Each active ECLS center should periodically review its accuracy in making this definitive diagnosis.

Surgical complications and procedures in neonates on extracorporeal membrane oxygenation.

We report our experience from May 1985 to January 1991 with surgical complications and procedures performed in neonates on extracorporeal membrane oxygenation (ECMO) (218 venoarterial and 7 venovenous bypass). Eleven children older than 1 month were excluded. Total complications were 96 in 67 patients and included: bleeding (37), problems with initial cannula placement (17), thrombus formation (15), hemothorax, pneumothorax, or effusions (11), mechanical problems (11), and miscellaneous (5). Forty-eight procedures were performed in 37 patients while on ECMO. These were recannulation or reposition of cannulas (14), tube thoracostomy (11), cardiac surgery (6), cardiac catheterization (4), repair of congenital diaphragmatic hernia (5), thoracotomy (4), and others. Twenty-eight complications occurred in 15 of the 27 patients who died. Mortality rate was 12% for the entire group. Primary causes of death were hypoplastic lung (11), cardiac (8), sepsis (4), intraventricular hemorrhage (2), and pulmonary hypertension (2). No deaths were due solely to complications except for the two patients with intraventricular hemorrhage. Mortality in neonates who had complications while on ECMO was significantly higher (P less than .005) than in patients without complications. Hemorrhagic and thoracic complications were associated with higher mortality (P less than .001). Mortality was not affected by mechanical problems, thrombus formation, or catheter-related problems. While on ECMO cardiac defects, diaphragmatic hernia, lobar emphysema, and other conditions can be safely corrected. The use of echocardiography to position the cannulas, better control of coagulation factors and improvement in equipment may ultimately decrease complications.

Survival of patients with congenital diaphragmatic hernia during the ECMO era: an 11-year experience.

BACKGROUND/PURPOSE: Congenital diaphragmatic hernia (CDH) is associated with significant mortality and morbidity. To evaluate the impact of extracorporeal membrane oxygenation (ECMO) on survival, a review of our experience with CDH patients was initiated. METHODS: The authors performed a retrospective nonrandomized analysis of 98 consecutive CDH patients who were ECMO candidates, and were symptomatic within the first day of life, and underwent repair between May 1985 and May 1996. The patients were divided into three groups: Group 1 (n = 38) refers to patients who were clinically stable and underwent repair before 48 hours of age and did not need ECMO rescue; Group 2 (n = 29) consists of patients who underwent repair but required ECMO rescue; and Group 3 (n = 31) refers to patients who met ECMO criteria preoperatively and required ECMO for stabilization and later underwent repair on ECMO. The Kaplan-Meier survival graph was used for survival analysis. RESULTS: During the 11-year span, the overall survival rate of all CDH patients was 72% (71 of 98). The survival rate of patients who did not require ECMO support was 92% (35 of 38), whereas patients who required ECMO after repair had a 72% (21 of 29) survival rate. These were compared with a 48% (15 of 31) survival rate for those undergoing repair on ECMO. The differences in survival among the three groups were statistically significant using the log-rank test (P = .0018). CONCLUSIONS: Survival was significantly better for infants who underwent successful repair without ECMO than those who required ECMO rescue pre- or postrepair. The overall improved survival of CDH patients to 72% compared with historical controls of 38% to 58% may be attributed to ECMO, but the requirement of ECMO before repair, as well as the presence of congenital anomalies (P < .01), prematurity (P < .01), the need for a Gore-Tex patch at repair (P < .05), prenatal diagnosis at less than 25 weeks' gestation (P < .01), and the occurrence of an intracranial hemorrhage (P < .01), decreases the chances of survival.

Retaining extracorporeal membrane oxygenation cannulae after extracorporeal support in the neonate: is it safe?

The retention of extracorporeal membrane oxygenation (ECMO) cannulae of ECMO is discontinued was originally developed to avoid reexploration of the neck in patients who may require a second course of ECMO. Because of the incidence, at the authors' institution, of thrombi noted on the ends of retained cannulae and their potential to cause significant morbidity, a critical review of this procedure was initiated. A telephone survey of 72 Extracorporeal Life Support Organization (ELSO) centers was conducted, and ELSO registry forms were requested for patients who had their cannulae retained. Twenty-four of these centers had performed the procedure of retaining ECMO cannulae. There were 324 neonatal and pediatric patients who had their cannulae retained, with 41 patients (12%) requiring a second course of ECMO and 17 of 41 (41%) surviving the second course. Twelve of the 24 ELSO centers that retain cannulae have reported complications. Analyses of the patients who had their cannulae retained showed that the three best predictors for requiring a second course of ECMO were the diagnosis of congenital diaphragmatic hernia (CDH) a high oxygenation index just before the initiation of ECMO, and a lengthy first ECMO course. The only difference between the survivors and nonsurvivors of the second course of ECMO was the length of the first ECMO course (P < .05). Five of the 25 patients who required two courses of ECMO had serious complications from their retained cannulae and all were nonsurvivors. The authors conclude that patients with retained ECMO cannulae are at high risk for developing thrombi, which can lead to severe embolic events. Therefore, the procedure of retaining cannulae should only be used in patients at high risk for requiring a second course of ECMO and not for the convenience of surgical availability to remove the cannulae.

Timing of intracranial hemorrhage during extracorporeal life support.

This study was conducted to determine the timing of intracranial hemorrhage (ICH) in patients on extracorporeal life support (ECLS) to improve the use of the head ultrasound in the detection of ICH. A review was conducted of all neonatal ECLS patients at the neonatal intensive care nursery at Kosair Children's Hospital in Louisville, Kentucky, from May, 1985 through November, 1994 to establish a study group of infants in whom an ICH developed while on ECLS. Thirty infants who had an ICH (excluding subarachnoid hemorrhage and infarction) on ECLS were included in the study. Data were collected that included patients demographics, age at initiation of ECLS, duration of ECLS, type of ECLS support (venoarterial or venovenous), oxygenation index and last arterial blood gas before ECLS, hours of ECLS before ICH, and grade of ICH. ICH occurred in 9.9% of the neonatal patients requiring ECLS. These included 8 infants with a Grade I bleed, 1 infant with a Grade II, 4 infants with a Grade III, and 17 infants with a Grade IV. Ten of the 30 patients had sepsis as their primary diagnosis, and these infants were more likely to have an ICH while on ECLS compared to nonseptic infants (p < 0.02). The Kaplan-Meier curve showed that 50% of ICHs occurred in the first 24 hours of ECLS, 75% by 48 hours, and that 85% of ICHs occurred within 72 hours of initiation of bypass. There was no difference in timing of ICH in the septic infants compared to the nonseptic infants. The late occurring bleeds (> 72 hours) were all associated with significant neurologic changes or with multiorgan failure. It is concluded that daily head ultrasounds should be performed during the first 3 days of ECLS because most ICHs (85%) occur in the first 72 hours of cardiopulmonary bypass. In this era of cost containment, subsequent head ultrasounds should be obtained with changes in the infant's neurologic status or with the development of multiorgan failure.

Evaluation of post extracorporeal membrane oxygenation follow-up testing.

The purpose of this study was to evaluate all post extracorporeal membrane oxygenation (ECMO) tests for their ability to detect any change in the incidence of unanticipated medical problems, and their charge to the patient. The current post ECMO protocol consists of the following tests: brain stem auditory evoked response, head computed tomography, cerebral blood flow, head ultrasonography, electroencephalography, eye examination for retinopathy of prematurity, and pneumocardiography. A retrospective review was conducted for all surviving neonatal ECMO patients treated from January, 1985, to December, 1994. The results of each test were classified as either normal, having a minor abnormality, or having a major abnormality. Statistical analyses were performed on each test comparing the incidence of minor and major abnormalities to all neonates in the neonatal intensive care nursery. Two hundred ninety-six infants survived their course on ECMO, and composed the study population. There were no significant differences between the incidence of abnormal results compared with the expected values for the following tests: cerebral blood flow (p=0.13), the eye examination (p=0.54), and pneumocardiography (p=0.22). The analyses for the brain stem auditory response, head computed tomography, head ultrasonography, and electroencephalography showed higher than expected incidences of abnormal results (p < 0.01). The data also were evaluated for major abnormalities on computed tomography and head ultrasonography. Of 161 infants who had both tests performed, 11 (6.8%) had normal head ultrasonography results, yet had a major abnormality noted on computed tomography (p < 0.01). This study is the first to review the current post ECMO protocol comprehensively, and the results suggest excluding the cerebral blood flow, eye, and pneumocardiography tests. This would result in a significant savings of $1,400 without compromising patient care. In addition, comparisons of neuroradiographic studies indicate that computed tomography of the head is sensitive enough to detect all central nervous system abnormalities that were found by ultrasonography. Excluding the post ECMO head ultrasonography, an additional savings of $300 would occur. These recommended changes reflect the current post ECMO protocol at Kosair Children's Hospital.

Use of two-dimensional and contrast echocardiography for venous cannula placement in venovenous extracorporeal life support.

The objective of this study was to determine the efficacy of two-dimensional and contrast echocardiograms to identify venous cannula position. Sequential sampling of 20 infants was evaluated by contrast echocardiography after meeting institutional criteria for extracorporeal life support. Each infant was placed on venovenous extracorporeal life support using a double-lumen cannula. After surgical placement was thought to be satisfactory, optimal two-dimensional images of the cannula were obtained via a subxiphoid or apical view and 2 ml agitated normal saline were injected rapidly into the nearest infusion port. Patient demographics and mixed venous saturations were noted. Distance of the venovenous cannula to tricuspid valve and distance of the venovenous cannula from the intra-atrial septum was recorded. Echocardiograms were available for review on 18 of the 20 patients. Position of the venovenous cannula in relationship to the tricuspid valve was as follows: < 5 mm (8); 5-10 mm (5); > 10 mm (5). Mixed venous saturations decreased, which indicated less recirculation when the orientation of the tip of the cannula was toward the lateral wall in those who required repositioning. The authors conclude that two-dimensional and contrast echocardiography aid in the positioning of the venovenous cannula. Satisfactory position is approximately 5 mm from the tricuspid valve, with orientation toward the lateral wall of the right atrium.