Elsevier

Resuscitation

Volume 60, Issue 3, March 2004, Pages 253-261
Resuscitation

The effect of mild therapeutic hypothermia on renal function after cardiopulmonary resuscitation in men

https://doi.org/10.1016/j.resuscitation.2003.11.006Get rights and content

Abstract

Background: Mild therapeutic hypothermia (MTH) improves neurological outcome in patients after cardiac arrest. From animal and human studies it appears that hypothermia impairs renal function. The aim of this study was to examine the effects of MTH on renal function in humans. Methods: Patients were participants recruited in one of the centres of the hypothermia after cardiac arrest-multicenter trial. We measured serum creatinine and creatinine clearance (CCr) within 24 h of MTH, at 4 hourly intervals. Patients were followed for acute renal failure and need for renal supportive therapy for 28 days. Results: We included 60 patients (32 hypothermic, 28 normothermic). Median serum creatinine on admission was [{119 μmol/l (IQR 108–133)} {1.35 mg/dl (IQR 1.22–1.50)}] in hypothermic and [{114 μmol/l (IQR 99–131)} {1.29 mg/dl (IQR 1.12–1.48)}] in normothermic patients, and decreased to [{69 μmol/l (IQR 62–84)} {0.78 mg/dl (IQR 0.70–0.95)}] in the hypothermic group and to [{88 μmol/l (IQR 71–123)} {1.00 mg/dl (IQR 0.80–1.39)}] in the normothermic group within 24 h. CCr was decreased on admission. Within 24 h CCr improved to normal values in normothermic patients [1.53 ml/s (IQR 1.15–2.35) {92 ml/min (IQR 69–141)}] and remained low in hypothermic patients [0.88 ml/s (IQR 0.63–1.38) {53 ml/min (IQR 38–83)}] (P=0.0006). No difference was found between the groups in the development of acute renal failure or the need for renal supportive therapy. Conclusion: Twenty four hours of MTH was associated with a delayed improvement in renal function. This was not reflected in the serum creatinine values, which were low in the hypothermic group. This transient impaired renal function appeared to be completely reversible within 4 weeks.

Sumàrio

Contexto: A terapêutica com hipotermia ligeira (MTH) melhora o prognóstico neurológico nos doentes após paragem cardı́aca. Dos estudos animais e humanos parece que a hipotermia afecta a função renal. O objectivo deste estudo é examinar os efeitos da MTH na função renal em humanos. Métodos: Os doentes foram recrutados de um dos centros do ensaio multicêntrico de hipotermia após paragem cardı́aca. Foi medida a creatinina sérica e a clearance da creatinina (CCr) durante 24 h de MTH, em intervalos de 4 horas. Os doentes foram seguidos durante 28 dias, durante os quais se observou o desenvolvimento de Insuficiência renal e a necessidade de terapêutica de suporte dialı́tico. Resultados: Foram incluı́dos no estudo 60 doentes (32 hipotermicos, 28 normotermicos). A creatinina sérica média na admissão foi de (119 μmol/l (IQR 108–133) (1.35 mg/dl (IQR 1.22–1.50) no grupo hipotermico e (114 μmol/l (IQR 99–131) (1.29 mg/dl (IQR 1.12–1.48) nos doentes normotérmicos, e diminuı́da em 24 horas para (69 μmol/l (IQR 62–84) (0.78 mg/dl (IQR 0.70–0.95) no grupo hipotérmico e para (88 μmol/l (IQR 71–123) (1.00 mg/dl (IQR 0.80–1.39) no grupo normotermico. A CCr estava diminuı́da na admissão. Após 24 h a CCr melhorou para valores normais nos doentes normotermicos (1.53 ml/s(IQR 1.15–2.35) (92 ml/min(IQR 69–141)) e permaneceu baixa nos doentes do grupo hipotermico (0.88 ml/s(IQR 0.63–1.38) (53 ml/min(IQR 38–83) (P=0.0006). Não foi encontrada nenhuma diferença entre os grupos no desenvolvimento de insuficiência renal aguda ou na necessidade de terapêutica de suporte renal. Conclusão: As 24 h de MTH foi associada a um atraso na melhoria da função renal. Isto não se reflectiu nos valores séricos da creatinina, que foram baixos no grupo da hipotermia. Esta alteração transitória da função renal parece estar completamente revertida dentro de 4 semanas.

Resumen

Antecedentes: La hipotermia terapéutica leve (MTH) mejora el resultado neurológico en pacientes después de paro cardı́aco. A partir de estudios humanos y en animales se ve que la hipotermia daña la función renal. El objetivo de este estudio fue examinar los efectos de la MTH sobre la función renal en humanos. Métodos: los pacientes fueron los reclutados en uno de los centros para participar en el estudio multicéntrico de hipotermia después del paro cardı́aco. Medimos creatinina sérica y clearance de creatinina(CCr) dentro de 24 h de MTH, en 4 intervalos horarios. Los pacientes fueron seguidos buscando falla renal aguda y necesidad de terapia de apoyo renal por 28 dı́as. Resultados: Incluimos 60 pacientes (32 hipotérmicos, 28 normotérmicos). La mediana de creatinina sérica al ingreso fue [{119 μmol/l (IQR 108–133)} {1.35 mg/dl(IQR 1.22–1.50)}] en los pacientes hipotérmicos y [{114 μmol/l (IQR 99–131)} {1.29 mg/dl (IQR1.12–1.48)}] en pacientes normotérmicos, y disminuyó a [{69 μmol/l (IQR 62–84)} {0.78mg/dl(IQR 0.70-0.95)}] en el grupo hipotérmico y a [{88 μmol/l (IQR 71–123)} {1.00mg/dl (IQR 0.80–1.39)}] en el grupo normotérmico dentro de las 24 h. El CCr estaba disminuido al ingreso. Dentro de 24 h mejoró hasta valores normales en pacientes normotérmicos [1.53 ml/s (IQR 1.15–2.35) {92 ml/min (IQR 69–141)}] y se mantuvo bajo en los pacientes hipotérmicos [0.88ml/s (IQR 0.63–1.38) {53 ml/min (IQR 38–83)}] (P=0.0006). No se encontró diferencia entre los grupos en el desarrollo de falla renal aguda o en la necesidad de terapia de apoyo renal. Conclusión: Se asoció las 24 horas de MTH con una demora en la mejorı́a de la función renal. Esto no se reflejó en los valores séricos de creatinina, que eran bajos en el grupo hipotérmico. Esta función renal transitoriamente dañada resultó estar completamente reversible dentro de 4 semanas.

Introduction

Renal failure has been observed in patients resuscitated from cardiac arrest with an incidence of between 12% [1] and 28% [2]. Transient impaired renal function is common in patients surviving cardiac arrest [3]. As there is evidence that hypothermia has positive effects on cerebral outcome after ischaemic brain damage [4], [5], [6] many patients now may be treated with this technique. However, animal [7] and human [8], [9] studies have shown impaired renal function during induced hypothermia.

In an uncontrolled pilot study of 27 patients with suspected ischaemic brain injury due to cardiac arrest we observed a 40% reduction in median serum creatinine levels {(122–73 μmol/l (1.38–0.83 mg/dl)} within 24 h of induced mild hypothermia [10]. These preliminary results might suggest a beneficial effect of induced mild hypothermia on renal function after cardiac arrest and cardiopulmonary resuscitation.

The aim of this explorative study within a randomized controlled multicenter trial, was to examine the effect of total body cooling on creatinine clearance and serum creatinine, compared to standard treatment without cooling, in patients after cardiac arrest.

Section snippets

Participants/patients

This study was an explorative analysis of participants in a multicentre study (HACA-clinical trial, hypothermia after cardiac arrest) designed to investigate the effect of induced mild hypothermia on neurological outcome after global brain ischaemia due to ventricular fibrillation cardiac arrest [6]. In a subgroup of these patients, recruited at the Department of Emergency Medicine at the University of Vienna, School of Medicine (tertiary care hospital with 2100 beds), renal function in

Participant flow and numbers analyzed

From March 1996 until June 2000, 734 patients after successful cardiopulmonary resuscitation were admitted to the Department of Emergency Medicine at the University Hospital of Vienna, one center of the HACA-clinical trial. At the emergency department 88 fulfilled the inclusion criteria and 44 were allocated to either the treatment or control group. In the hypothermia group one patient did not receive allocated intervention, in six patients intervention was discontinued and five had to be

Discussion

The present study showed that mild therapeutic hypothermia, compared to standard treatment without cooling in patients resuscitated from ventricular fibrillation cardiac arrest, entailed a decrease in serum creatinine concentrations. In contrast, the serum creatinine clearance was low on admission in both groups, and showed a rapid improvement in the normothermic group, whereas recovery of serum creatinine clearance was delayed in the hypothermic group. Renal function was not different between

Conclusion

This study showed a “spurious” improvement of renal function based on serum creatinine measurements in patients with cardiac arrest treated with induced mild hypothermia. The creatinine clearance showed no immediate improvement as compared to the rapid recovery observed in patients on standard treatment. The impairment of renal function due to hypothermia had no effect on renal function at 4 weeks after the index event. These findings have implications for the diagnosis of postresuscitation

References (25)

  • C. Metz et al.

    Moderate hypothermia in patients with severe head injury: cerebral and extracerebral effects

    J. Neurosurg.

    (1996)
  • A. Zeiner et al.

    Mild resuscitative hypothermia to improve neurological outcome after cardiac arrest. A clinical feasibility trial. Hypothermia after cardiac arrest (HACA) study group

    Stroke

    (2000)
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