Cardiac surgery patients present considerable variation in pre‐operative hemodynamic variables

Abstract

This study is unique because hemodynamic reference data in cardiac surgery patients have not been published previously. The intra-patient variations were unexpectedly high in most hemodynamic variables and demonstrate the difficulties of using hemodynamic parameters as a guidance for treatment and indicate that goal-oriented therapy using currently accepted values may result in over-treatment in some patients.

Variable pre‐operative hemodynamics in cardiac surgery

“…In contrast, increasing the mean arterial pressure during cardiopulmonary bypass to >80 mmHg revealed controversial results regarding cardiac and neurological complications 6,7 . It is of note that the goal of an SvO 2 >70% as set up by Poloenen et al 5 is comparable to the pre‐operative mean values observed by Sloth et al 1 in the present study; thus, what we have learned about how to treat our patients post‐operatively seems not so far from normal physiology.…”

“…With great interest we have read the study by Sloth et al on variations in pre‐operative hemodynamics in patients scheduled for cardiac surgery, showing that flow‐related hemodynamic variables as well as arterial blood pressure show marked intra‐ and inter‐patient variations and are sometimes lower (or higher) than the hemodynamic goals commonly accepted in the post‐operative situation 1 . This is a remarkable study since most of our knowledge on pre‐operative hemodynamics in cardiac surgery patients has been gathered during cath lab studies or in the immediate period before induction of anesthesia and not in unstressed, quietly sleeping patients.…”

Transfusion Strategy: Impact of Haemodynamics and the Challenge of Haemodilution

“…A previous study found considerable interpatient differences and intrapatient variation in patients monitored the night before cardiac surgery (Figure 7) [91]. The most pronounced intrapatient variation was found in the cardiac index, ranging from 1.9 to 5.3 l/min/m 2 .…”

“…Although the number of patients in the study was low the conclusion was that intrapatient variation was unexpectedly high in most hemodynamic variables. This demonstrated the challenge in using hemodynamic parameters to guide treatment and indicated that goal oriented therapy using currently accepted values may result in overtreatment in some patients [91]. …”

Reply

“…Thanks for the opportunity to respond to the comments from Heringlake et al The conclusion from our study 1 was that the intra‐patient variation was unexpectedly high in most variables. Further, as routine pre‐operative monitoring is impossible for obvious reasons, our findings indicate difficulties when acting on single hemodynamic variables and further indicate that goal‐oriented therapy may result in overtreatment compared with pre‐operative status.…”