How does rewarming temperature affect bleeding after mitral valve repair?

Abstract

Objective

So far, evidence is scarce regarding the impact of rewarming temperature on bleeding after cardiac surgery under cardiopulmonary bypass (CPB). We seek to evaluate how rewarming temperature affects postoperative bleeding in patients undergoing mitral valve repair.

Methods

Clinical, anesthesia and CPB data were analyzed for 379 adults undergoing isolated mitral regurgitation repair. Platelet levels (1000/μL) were divided into three groups: low, 53–164 (n = 128); medium, 165–208 (n = 126); and high, 209–906 (n = 125). The primary endpoint was chest drainage volume (mL) at 24 postoperative hours. To delineate the degree and impact of rewarming, a variable “rewarming/cooling ratio” was defined as: peak rewarming temperature (°C) divided by nadir cooling temperature (°C). General linear models were used to evaluate factors associated with the volume of 24-h chest drainage.

Results

Mean flow rate was 2.7 ± 0.1 L/min/m², nadir core temperature 30.7 ± 1.3°C and peak rewarming temperature 36.2 ± 0.5°C. The “rewarming/cooling ratio” averaged 1.133 ± 0.044.

Postoperatively, nadir platelet count was 115 ± 46 k/μL, and chest drainage averaged 344 ± 181 mL at 24 h. Two patients underwent re-exploration for bleeding (0.5%). Transfusion was required in 85 patients (22.4%).

Gender (F = 20.585, p < 0.001), platelet count (F = 3.875, p = 0.024), fibrinogen (F = 4.241, p = 0.040), and chest incision (F = 58.097, p < 0.001), rather than the rewarming temperature (F = 2.322, p = 0.128), were factors significantly associated with 24-h chest drainage.

A significant interaction existed between platelet levels and “rewarming/cooling ratio” (F = 3.717, p = 0.025), i.e., with a higher “rewarming/cooling ratio”, 24-h chest drainage tended to increase in the low platelet group, and to decrease in patients with high and medium platelet levels.

Conclusions

In this series of patients undergoing isolated mitral regurgitation repair, gender, platelet count, fibrin and chest incision, rather than rewarming temperature, were independent factors significantly associated with postoperative bleeding. The impact of rewarming temperature on postoperative bleeding was modified by preoperative platelet levels. It is advisable to avoid excessive cooling during CPB and keep the cooling temperature at maximally allowable level.

Keywords

cardiopulmonary bypass cooling temperature mitral valve repair postoperative bleeding rewarming temperature transfusion

Get full access to this article

View all access options for this article.

References

Heimisdottir

Nielsen

Karlsson

, et al. Long-term outcome of patients undergoing re-exploration for bleeding following cardiac surgery: a SWEDEHEART study. Eur J Cardio Thorac Surg 2022; 62: ezac208.

Christensen

Krapf

Kempel

, et al. Costs of excessive postoperative hemorrhage in cardiac surgery. J Thorac Cardiovasc Surg 2009; 138: 687–693.

Shou

Zhou

Ong

, et al. Impact of intraoperative blood products, fluid administration, and persistent hypothermia on bleeding leading to reexploration after cardiac surgery. J Thorac Cardiovasc Surg 2024; 168: 873–884. e4.

Tan

. Benefits and risks of maintaining normothermia during cardiopulmonary bypass in adult cardiac surgery: a systematic review. Cardiovasc Ther 2011; 29: 260–279.

Engelman

Baker

Likosky

, et al. The society of thoracic surgeons, the society of cardiovascular anesthesiologists, and the American society of extracorporeal technology: clinical practice guidelines for cardiopulmonary bypass—temperature management during cardiopulmonary bypass. Ann Thorac Surg 2015; 100: 748–757.

Engelen

Himpe

Borms

, et al. An evaluation of underbody forced-air and resistive heating during hypothermic, on-pump cardiac surgery. Anaesthesia 2011; 66: 104–110.

Murphy

2nd Hessel

Groom

. Optimal perfusion during cardiopulmonary bypass: an evidence-based approach. Anesth Analg 2009; 108: 1394–1417.

Shaaban Ali

Harmer

Kirkham

. Cardiopulmonary bypass temperature and brain function. Anaesthesia 2005; 60: 365–372.

Hohn

Schweizer

Kalangos

, et al. Benefits of intraoperative skin surface warming in cardiac surgical patients. Br J Anaesth 1998; 80: 318–323.

10.

Sahu

Chauhan

Kiran

, et al. Neurocognitive function in patients undergoing coronary artery bypass graft surgery with cardiopulmonary bypass: the effect of two different rewarming strategies. J Cardiothorac Vasc Anesth 2009; 23: 14–21.

11.

Nathan

Wells

Munson

, et al. Neuroprotective effect of mild hypothermia in patients undergoing coronary artery surgery with cardiopulmonary bypass: a randomized trial. Circulation 2001; 104: I85–I91.

12.

Bar-Yosef

Mathew

Newman

, et al. Prevention of cerebral hyperthermia during cardiac surgery by limiting on-bypass rewarming in combination with post-bypass body surface warming: a feasibility study. Anesth Analg 2004; 99: 641–646.

13.

Nathan

Parlea

Dupuis

, et al. Safety of deliberate intraoperative and postoperative hypothermia for patients undergoing coronary artery surgery: a randomized trial. J Thorac Cardiovasc Surg 2004; 127: 1270–1275.

14.

Boodhwani

Rubens

Wozny

, et al. Effects of sustained mild hypothermia on neurocognitive function after coronary artery bypass surgery: a randomized, double-blind study. J Thorac Cardiovasc Surg 2007; 134: 1443–1450, discussion 51-2.

15.

Belway

Tee

Nathan

, et al. Temperature management and monitoring practices during adult cardiac surgery under cardiopulmonary bypass: results of a Canadian national survey. Perfusion 2011; 26: 395–400.

16.

Khuri

Alan Wolfe

Josa

, et al. Hematologic changes during and after cardiopulmonary bypass and their relationship to the bleeding time and nonsurgical blood loss. J Thorac Cardiovasc Surg 1992; 104: 94–107.

17.

Valeri

Feingold

Cassidy

, et al. Hypothermia-induced reversible platelet dysfunction. Ann Surg 1987; 205: 175–181.

18.

Cook

. Changing temperature management for cardiopulmonary bypass. Anesth Analg 1999; 88: 1254–1271.

19.

Cook

. Cerebral hyperthermia and cardiac surgery: consequences and prevention. Semin Thorac Cardiovasc Surg 2001; 13: 176–183.

20.

Essa

Zeynalov

Sandhaus

, et al. Low fibrinogen is associated with increased bleeding-related re-exploration after cardiac surgery. Thorac Cardiovasc Surg 2018; 66: 622–628.

21.

Ereth

Nuttall

Oliver

Jr , et al. Temperature and duration of cardiopulmonary bypass influence transfusion requirements. J Clin Anesth 1998; 10: 588–592.

22.

Grigore

Murray

Ramakrishna

, et al.

A core review of temperature regimens and neuroprotection during cardiopulmonary bypass: does rewarming rate matter?

Anesth Analg 2009; 109: 1741–1751.

23.

Newland

Tully

Baker

. Hyperthermic perfusion during cardiopulmonary bypass and postoperative temperature are independent predictors of acute kidney injury following cardiac surgery. Perfusion 2013; 28: 223–231.

24.

Shann

Likosky

Murkin

, et al. An evidence-based review of the practice of cardiopulmonary bypass in adults: a focus on neurologic injury, glycemic control, hemodilution, and the inflammatory response. J Thorac Cardiovasc Surg 2006; 132: 283–290.

25.

Browne

. Temperature management on cardiopulmonary bypass: is it standardised across Great Britain and Ireland? Perfusion 2022; 37: 221–228.