[Changes of myocardial dynamics in early stage of burn and effect of rapid fluid replacement in delayed resuscitation].
OBJECTIVE
To investigate the changes in myocardial dynamics in early phases of burn shock of dogs and the effects of rapid fluid infusion in delayed resuscitation.


METHODS
Twelve mongrel dogs were randomly divided into control (n=6) and burn (n=6) groups. The dogs in burn group were subjected to 35% total body surface area (TBSA) III degree burn and were resuscitated with lactate Ringer's solution 6 hours postburn. The volumes and rates of fluid infusion were controlled basically on the urinary output of 1.0 mlxkg(-1)xh(-1) and cardiac output (CO) of 70%-80% of pre-burn values. The mean arterial pressure (MAP), left ventricular systolic pressure (LVSP), maximum rate of intraventricular pressure rise/down (+/-dp/dt max) and cardiac index (CI) were determined at 0.5, 1,2, 6, 7, 8, 10 and 24 hours postburn.


RESULTS
The MAP, LVSP, +/-dp/dt max and CI were significantly lowered from their baseline and those of control group at 0.5 hour postburn, and they kept declining until 6 hours postburn. They showed a tendency of elevation and reached or approached the levels of that in control group within 2 hours of resuscitation, and the differences were not significant between the two groups 4 hours after burn (all P>0.05). The amount of infusion fluid within the first 4 hours of resuscitation was (3.63+/-0.99) ml/kg per 1% TBSA.


CONCLUSIONS
The myocardial dynamics is depressed in the early stage of burn, the effective way to improve it is to infuse a large amount of fluid rapidly when resuscitation is delayed.
Wang
De-wei
DW
Department of Burns, The First Municipal People's Hospital, Lianyungang 222002, Jiangsu, China. dwwang0518@yahoo.com.cn
Wang
Chang-hui
CH
Ding
Xiang-sheng
XS
Pei
Yong-dong
YD
Zhu
Shi-hui
SH
Liu
Shi-kang
SK
Ge
Sheng-de
SD
D000818:Animals; D002056:Burns / Q000503:physiopathology* / Q000628:therapy; D002302:Cardiac Output / Q000187:drug effects; D004195:Disease Models, Animal; D004285:Dogs; D005440:Fluid Therapy; D006321:Heart / Q000503:physiopathology*; D007552:Isotonic Solutions / Q000627:therapeutic use; D009200:Myocardial Contraction / Q000187:drug effects; D011897:Random Allocation; D012151:Resuscitation; D000077325:Ringer's Lactate
D007552:Isotonic Solutions; D000077325:Ringer's Lactate