Tepid hypothermic (32  C) circulatory arrest for total aortic arch replacement: a paradigm shift from profound hypothermic surgery

Abstract

In total aortic arch replacement (TARCH) using hypothermic circulatory arrest (HCA) and selective cerebral perfusion (SCP), postoperative cerebral complications, including metabolic abnormalities, are by no means rare. Furthermore, there is a lack of international guidelines for the optimal perfusion temperature and flow for SCP. Starting in 2008, TARCH was performed using tepid HCA at 32 °C. In the present study, 27 patients (group C) who underwent TARCH with deep hypothermia at the lowest rectal temperatures of 20-25 °C were retrospectively reviewed and compared with 23 patients (group W) who underwent TARCH with 32 °C tepid hypothermia. Preoperative patient characteristics and intraoperative and postoperative parameters were compared. Preoperative patient characteristics did not differ significantly between the two groups. Circulatory arrest time, cardiopulmonary bypass time, operating time, amount of blood transfused and postoperative neurological complications were significantly reduced in group W compared with group C. Our procedure of TARCH using tepid hypothermia at 32 °C was safe, and it significantly reduced all parameters of extracorporeal circulation time. However, this study has several limitations. To indicate the safety and usefulness of tepid HCA for TARCH, a further multifaceted study should be performed with a greater number of patients.

Right axillary and femoral artery perfusion with mild hypothermia for aortic arch replacement

“…HCA with SACP prevents a series of adverse effects caused by deep hypothermia [15-17] and shows excellent clinical outcomes. Given continuous improvements in aortic surgical techniques and perfection of CPB equipment in recent years, several surgeons have completed aortic arch surgery under mild hypothermia (30°C to 32°C) with satisfactory results [6,11,12,18]. Andreas Zierer and colleagues [6] reported on 245 aortic arch operations completed using selective cerebral perfusion under mild hypothermia (30.5°C ± 1.4°C) in 2011 and obtained an operative mortality rate of 8% ( n  = 20) and post-operative PND and TND morbidity rates of 6% (n = 14) and 5% ( n  = 12), respectively.…”

Brain Protection in Type A Aortic Dissection

“…This level of deep cooling is nowadays still used by a lot of surgeons in the US but it is our impression that in Europe and Japan, the temperature at which the body circulation is arrested, is higher (20 -25°C, even 28°C) also obtaining good clinical results (17). Even tepid HCA (32°C) seems to compare favourably with deep HCA (20-25°C) (18). Immediately after a period of HCA follows a period of reactive hyperaemia or cerebral hyperperfusion followed by several hours of increased cerebrovascular resistance during which brain oxygen extraction is increased but cerebral blood flow may be inadequate (19).…”

Temperature Selection in Antegrade Cerebral Perfusion for Aortic Arch Surgery: A Meta-Analysis

“…Seven of the 18 studies included at least 100 patients (median, 92; interquartile range, 57 to 218) [9, 16, 18-21, 24, 25]. Seven studies emanated from Japan [9,14,16,17,23,25,26], four each from Europe [10,19,20,22] and North America [12,18,21,24], and three from China [11,13,15].…”

“…There were 1,215 patients in the "cold" cohort and 1,417 patients in the "warm" cohort. Overall, eight studies compared deep hypothermia (14.1 to 20 C) and moderate hypothermia (20.1 to 28 C) [9][10][11][12][13][14][15][16], five studies compared low-moderate hypothermia (20.1 to 24 C) and highmoderate hypothermia (24.1 to 28 C) [17][18][19][20][21], and five studies compared moderate and mild hypothermia [22][23][24][25][26]. Two studies that compared deep hypothermia with two levels of moderate hypothermia were subdivided into four study data points, with the deep hypothermia cohort as the reference [9,14].…”