Date Published: October 4, 2013
Publisher: Public Library of Science
Author(s): Chin-Fu Chang, Chao-Jui Li, Chih-Jan Ko, Tsung-Han Teng, Shih-Chang Lai, Mei-Chueh Yang, Chun-Wen Chiu, Chu-Chung Chou, Chih-Yu Chang, Yung-Chiao Yao, Lan-Hsin Wu, Han-Ping Wu, Wen-Liang Chen, Yan-Ren Lin, Pal Bela Szecsi.
To analyze whether urine output and urinalysis results are predictive of survival and neurologic outcomes in patients with non-traumatic out-of-hospital cardiac arrest (OHCA).
Information was obtained from 1,340 patients with non-traumatic OHCA who had achieved a sustained return of spontaneous circulation (ROSC). Factors that were associated with survival in the post-resuscitative period were evaluated. The association between urine output and fluid challenge in the early resuscitative period was analyzed and compared between the survivors and the non-survivors. The results of the initial urinalysis, including the presence of proteinuria and other findings, were used to evaluate the severity of vascular protein leakage and survival. The association between proteinuria and the neurologic outcomes of the survivors was also analyzed. The clinical features of capillary leakage were examined during the post-resuscitative period.
Of the 1,340 patients, 312 survived. A greater urine output was associated with a higher chance of survival. The initial urine output increased in proportion to the amount of fluid that was administered during early resuscitation in the emergency department for the survivors but not for the non-survivors (p<0.05). In the initial urinalysis, proteinuria was strongly associated with survival, and severe proteinuria indicated significantly poorer neurologic outcomes (p<0.05 for both comparisons). Proteinuria was associated with a risk of developing signs of capillary leakage, including body mass index gain and pitting edema (both p<0.001). The severity of proteinuria during the early post-resuscitative period was predictive of survival.
The survival rate of patients with out-of-hospital cardiac arrest (OHCA) is low. – Although a sustained return of spontaneous circulation (ROSC) can be initially established following resuscitation from non-traumatic OHCA in certain patients, many of these patients lose spontaneous circulation during the hospital stay due to continued damage from post-cardiac arrest syndrome. , , –.
Patients with OHCA who survive during the post-resuscitative period are at risk of developing a “sepsis-like” syndrome. ,  Due to similarities between the post-cardiac arrest state and sepsis, it has been postulated that early goal-directed hemodynamic optimization and strategies that aim to maintain a urine output above 0.5 ml/kg/h may improve the outcomes of OHCA survivors. ,  The early optimal urine output level during the ED resuscitative phase in patients with non-traumatic OHCA has not been established. We observed (i) that most OHCA survivors exhibited a median urine output >0.9 ml/kg/h during the ED resuscitative phase and (ii) that increased urine output indicated a higher probability of survival. Laurent et al. reported that an adequate fluid challenge led to a decrease in the severity of myocardial dysfunction in the post-resuscitative period.  In the present study, 122 survivors and 457 non-survivors each received more than 2,000 ml of a fluid challenge in the ED. The median urine output in the ED was significantly higher in the survivors than in the non-survivors. Similar patterns were noted when the administered fluid volume was either 2,001–3,000 ml or >3,000 ml. We therefore suspect that the stronger correlation that was observed between fluid input and urine output (indicating an early establishment of hemodynamic balance) was more important to survival than a single, massive fluid challenge.
The results of early urinalyses indicated initial systemic, I/R injury-induced vascular protein leakage. Most importantly, the severity of initial proteinuria predicted both survival and neurologic outcomes in the post-resuscitative period.