Continuous renal replacement therapy to reduce inflammation in a piglet hemorrhage-reperfusion extracorporeal membrane oxygenation model.

BACKGROUND: During extracorporeal membrane oxygenation (ECMO), circulation of blood across synthetic surfaces triggers an inflammatory response. Therefore, we evaluated the ability of continuous renal replacement therapy (CRRT) to remove cytokines and reduce the inflammatory response in a piglet hemorrhage-reperfusion ECMO model. METHODS: Three groups were studied: (i) uninjured controls (n = 11); (ii) hemorrhage-reperfusion while on venoarterial ECMO (30% hemorrhage with subsequent blood volume replacement within 60 min) (n = 8); (iii) treatment with CRRT after hemorrhage-reperfusion while on ECMO (n = 7). Hemodynamic parameters, oxygen utilization, and plasma and broncho-alveolar lavage (BAL) cytokine levels were recorded and lung tissue samples collected for histologic comparison. RESULTS: Whereas mean arterial pressures decreased among hemorrhage-reperfusion piglets, ECMO with CRRT did not significantly alter mean arterial pressures or systemic vascular resistance and was able to maintain blood flow as well as oxygen delivery after hemorrhage-reperfusion. Plasma interleukin (IL)-6 and IL-10, and BAL tumor necrosis factor (TNF)-α, IL-1ß, IL-6, IL-8, and IL-10 increased as a result of hemorrhage-reperfusion while on ECMO. After a 6-h period of CRRT, plasma IL-6 and BAL TNF-α, IL-6, and IL-8 levels decreased. CONCLUSION: Data suggest CRRT may decrease inflammatory cytokine levels during the initial phase of ECMO therapy following hemorrhage-reperfusion while maintaining cardiac output and oxygen utilization.

Late presentation of diaphragmatic hernia in a Pacific Island pediatric population.

BACKGROUND: Congenital diaphragmatic hernia (CDH) usually presents at birth with respiratory distress syndrome (RDS) and has a high mortality rate if not promptly recognized and treated. The incidence of CDH is reported to be 0.8 - 1.0/10,000 registered births. Less than 3% present after the neonatal period. In the latter, ie. late-presenting CDH (L-pCDH), the prognosis is improved because pulmonary hypoplasia does not develop. With the creation and application of a store-and-forward telemedicine system to the Pacific Island Health Care Project (PIHCP), we have come to realize that this rare condition ie., (L-pCDH) occurs with unusual frequency in the United States Associated Pacific Islands (USAPIs), especially those of the Federated States of Micronesia (FSM). METHODS: Information concerning CDH was identified from the archived data base of the over 3, 100 cases of the PIHCP as well as the composite data base of Tripler Army Medical Center (TAMC). The cases of CDH diagnosed after the neonatal period (> 30 days of age) were considered to have L-pCDH. The study period was from 1997 - 2006. RESULTS: During the study period (1997-2006), 12 cases of CDH were referred from the PIHCP. There was 1 case of CDH born at TAMC (beneficiary from Micronesia) during the same period. The number of births over the 10-year period of study was similar for the referral base (PIHCP) and TAMC. Five of the 12 cases in which the age at diagnosis could be established, were L-pCDH from the PIHCP. The one case of CDH born at TAMC, during the 10 year period, was diagnosed in the neonatal period (< 30 days of age). DISCUSSION: These results confirm that CDH occurs with increased frequency in the USAPIs as contrasted to the frequency in the developed world. The incidence of L-p CDH is far in excess in the USAPIs. This review highlights the fact that this group of patients can be easily identified using tele-techology (attached chest X-rays demonstrating stomach and/or bowel gas in the chest) thus allowing remote diagnosis and referral for ultimate surgical correction of this potentially lethal condition. Infants and children with CDH: provided excellent graduate medical education (GME) for residents-in-training; are afforded advanced surgical treatment unavailable in the remote jurisdictions of the Pacific; and, following surgery, are restored to health to return to their homes so as to become contributing members of society. CONCLUSION: CDH, especially L-pCDH occurs with increased frequency in the USAPIs. The Web-based-store-and-forward telemedicine PIHCP allows for remote diagnosis. Patients so identified are transported to TAMC for definitive treatment. These patients provide excellent GME to our residents-in-training. Following surgical correction these patients are restored to health to return to their homes to mature and become contributing members of society.

ECMO with vasopressor use during early endotoxic shock: Can it improve circulatory support and regional microcirculatory blood flow?

INTRODUCTION: While extracorporeal membrane oxygenation (ECMO) is effective in preventing further hypoxemia and maintains blood flow in endotoxin-induced shock, ECMO alone does not reverse the hypotension. In this study, we tested whether concurrent vasopressor use with ECMO would provide increased circulatory support and blood flow, and characterized regional blood flow distribution to vital organs. METHODS: Endotoxic shock was induced in piglets to achieve a 30% decrease in mean arterial pressure (MAP). Measurements of untreated pigs were compared to pigs treated with ECMO alone or ECMO and vasopressors. RESULTS: ECMO provided cardiac support during vasodilatory endotoxic shock and improved oxygen delivery, but vasopressor therapy was required to return MAP to normotensive levels. Increased blood pressure with vasopressors did not alter oxygen consumption or extraction compared to ECMO alone. Regional microcirculatory blood flow (RBF) to the brain, kidney, and liver were maintained or increased during ECMO with and without vasopressors. CONCLUSION: ECMO support and concurrent vasopressor use improve regional blood flow and oxygen delivery even in the absence of full blood pressure restoration. Vasopressor-induced selective distribution of blood flow to vital organs is retained when vasopressors are administered with ECMO.

Comparison of home and clinic well-baby visits in a military population.

Patient satisfaction is an indicator of quality of care received. Home-visit programs are associated with increased satisfaction and equivalent clinical outcomes but increased cost, compared with clinic visits. We hypothesized that home visits for routine well-child care would also be associated with increased satisfaction and equivalent outcomes. One thousand infants born at Tripler Army Medical Center were identified, and 630 were enrolled. Army and Air Force dependents received 2-week clinic visits. Navy and Marine Corps dependents were offered home visits. At 4 to 6 weeks, families completed a questionnaire. Maternal satisfaction and quality of anticipatory guidance were higher in the home-visit group. Clinical outcomes were equal. Home visits for routine well-child care are valid and are associated with greater maternal satisfaction, better anticipatory guidance, and equivalent clinical outcomes.

ECMO Maintains Cerebral Blood Flow During Endotoxic Shock in Piglets.

Cerebrovascular injury while on extracorporeal membrane oxygenation (ECMO) may be caused by excessive brain perfusion during hypoxemic reperfusion. Previous studies have postulated that the most vulnerable period of time for cerebrovascular injury is during the transfer period to ECMO. Therefore, our objective was to compare brain perfusion and hemodynamics in a piglet endotoxic shock ECMO model. The effect of ECMO flow on microcirculation of different brain regions was compared between 10 control pigs and six pigs (7-10 kg) administered IV endotoxin to achieve a drop in mean arterial blood pressure (MAP) of at least 30%. Cardiac output (CO), brain oxygen utilization, and microcirculatory blood flow (BF) were compared at baseline and 2 hours after ECMO stabilization. Matching ECMO delivery with baseline CO in control animals increased perfusion (p < 0.05) in all areas of the brain. In contrast, with endotoxin, ECMO returned perfusion closer to baseline levels in all regions of the brain and maintained brain tissue oxygen consumption. Both control and endotoxic pigs showed no evidence of acute neuronal necrosis in histologic cerebral cortical sections examined after 2 hours of ECMO. Results show that during endotoxic shock, transition to ECMO can maintain brain BF equally to all brain regions without causing overperfusion, and does not appear to cause brain tissue histopathologic changes (hemorrhage or necrosis) during the acute stabilization period after ECMO induction.