Induced hypothermia in the management of refractory low cardiac output states following cardiac surgery in infants and children

Abstract

Post-operative low cardiac output states remain a major cause of mortality following cardiac surgery in infants and children. Since 1979 we have used moderate induced whole-body hypothermia in the management of low-output states refractory to conventional modes of therapy. This is based not only upon the relationship between body temperature and oxygen consumption, but also on experimental work showing a beneficial effect of cooling upon myocardial contractility, particularly when there is pre-existing impairment of ventricular function. Between July 1986 and June 1990, 20 children with refractory low-output states were cooled by means of a thermostatically controlled water blanket to a rectal temperature of 32-33 degrees C. The median age was 12 months (1 week-11 years) with a median weight of 6 kg (3.5-33 kg). Ten children survived to leave hospital while a further two made a haemodynamic recovery. There was a marked reduction in heart rate (P < 0.001). The mean arterial pressure rose (P = 0.037) while there was a fall in mean atrial pressure (P < 0.001). There was a significant improvement in the urine output (P = 0.002). A fall in the platelet count (P < 0.001) was not accompanied by any change in the white cell count (P = 0.15). Although it is impossible to say whether cooling influenced the outcome in any of these children, it was usually effective in stabilising their clinical condition. The technique is simple and has a sound theoretical basis.(ABSTRACT TRUNCATED AT 250 WORDS)

Therapeutic hypothermia and controlled normothermia in the intensive care unit: Practical considerations, side effects, and cooling methods*

“…The fact that hypothermia can indeed improve circulatory parameters is shown by its successful usage in five small studies (three in pediatric patients and two in adults) to improve circulation and reverse refractory cardiac shock following cardiac surgery (87)(88)(89)(90)(91). Two small studies have reported that hypothermia can be used safely and effectively in hemodynamically unstable patients who remain comatose following cardiac arrest (166,167).…”

The determinants of right ventricular function in patients with atrial septal defect

“…The loss of RV contractile function and pulmonary dysfunction is the main cause of exercise intolerance in patients with congenital heart defects [6]. RV dysfunction may also cause serious problems in 0167 maintaining adequate cardiac output after surgical correction of congenitally malformed hearts [7,8].…”

Induced Hypothermia Prior to Left Ventricular Assist Device

“…Dalrymple-Hay and coworkers, 17 in a population of infants and children with congenital heart disease undergoing corrective cardiac surgery, reported the use of IH in 57 patients with cardiogenic shock following cardiac surgery; 54% had benefits in hemodynamic parameters and mortality. Single-institution experiences by Moat and coworkers 18 and Deakin and coworkers 19 have reported comparable survival results in smaller pediatric populations. This case appears to be the first report describing a heart transplant patient who was successfully resuscitated and treated with therapeutic hypothermia prior to surgical placement of a left ventricular assist device.…”

“…13 The cardioprotective effects of IH have been applied in adult and pediatric cardiac surgery patients to manage refractory cardiogenic shock; to date, 5 case series have reported on the use of IH in patients with refractory cardiogenic shock following cardiac surgery. [15][16][17][18][19] Yahagi and coworkers 15 found that in 10 adult patients with cardiogenic shock following cardiac surgery, despite the use of intra-aortic balloon pumps (IABPs) and catecholamines, they were more successful in weaning patients from IA-BPs with the use of IH. Moriyama and coworkers 16 reviewed cardiac hemodynamics in 8 adult postcardiotomy ventricular failure patients and found significant improvements in tissue oxygen consumption through varying durations of hypothermia.…”