Related Experiment Videos
[A study of changes in extravascular lung water after extracorporeal circulation--clinical and experimental studies
1Second Department of Surgery, Faculty of Medicine, Ryukyu University, Okinawa, Japan.
Abstract:
Accumulation of water in the interstitial spaces of the lung disturbs gas exchange, and can progress to pulmonary edema, a critical complication. To assess the prophylactic measures that can be taken to prevent such a pulmonary complication, we have clinically and experimentally investigated the factors that affect extravascular lung water (EVLW), especially, those factors which can be used to decrease the EVLW. Clinically, the relations of the change rate of EVLW (%EVLW) to colloid osmotic pressure (COP), urine out put and water balance were studied in post-operative patients after Extracorporeal circulation. It was found that an increase in COP, and/or an increase in urine out put contributed in lowering the EVLW. A minus water balance also contributed to lower the EVLW. To clarify further the roles of factors in regards to EVLW, an experiment was conducted using dogs. The dogs were intubated and put under controlled mandatory ventilation (CMV) using a respirator. They were divided into the following 4 groups and their EVLW values were measured. Group I; CMV only. Group II; CMV with 10 cmH2O positive end-expiratory pressure (PEEP). Group III; CMV (with 10 cmH2O PEEP) with continuous infusion of normal saline. Group IV; CMV (with 10 cmH2O PEEP) with plasma infusion and drug induced diuresis. In the first 3 groups, EVLW increased in respect to time. In group IV, in which COP was elevated, and a high urine output level and negative water balance was maintained by infusion of plasma and drug induced diuresis, the EVLW did not increase but decrease in respect to time. These experimental results were in accordance to the clinical observations. Therefore, from the clinical and experimental findings, it can be said that vigorous use of diuretics and infusion of plasma decreases the post-operative EVLW. This implicated prevention of the accumulation of water in the pulmonary interstitium, preventing pulmonary complications.