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Intensified thermal management for patients undergoing transcatheter aortic valve implantation (TAVI)



Transcatheter aortic valve implantation via the transapical approach (TAVI-TA) without cardiopulmonary bypass (CPB) is a minimally invasive alternative to open-heart valve replacement. Despite minimal exposure and extensive draping perioperative hypothermia still remains a problem.


In this observational study, we compared the effects of two methods of thermal management on the perioperative course of core temperature. The methods were standard thermal management (STM) with a circulating hot water blanket under the patient, forced-air warming with a lower body blanket and warmed infused fluids, and an intensified thermal management (ITM) with additional prewarming using forced-air in the pre-operative holding area on the awake patient.


Nineteen patients received STM and 20 were treated with ITM. On ICU admission, ITM-patients had a higher core temperature (36.4 ± 0.7°C vs. 35.5 ± 0.9°C, p = 0.001), required less time to achieve normothermia (median (IQR) in min: 0 (0-15) vs. 150 (0-300), p = 0.003) and a shorter period of ventilatory support (median (IQR) in min: 0 (0-0) vs. 246 (0-451), p = 0.001).


ITM during TAVI-TA reduces the incidence of hypothermia and allows for faster recovery with less need of ventilatory support.

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Aortic valve replacement with cardiopulmonary bypass (CPB) is currently the treatment of choice for symptomatic aortic stenosis but carries a significant risk of morbidity and mortality, particularly in frail elderly patients with severe comorbidities [1]. Transcatheter aortic valve implantation via the transapical approach (TAVI-TA) without CPB is a promising alternative in selected patients [2, 3] but is associated with a high risk of perioperative hypothermia with several adverse side effects [47]. Hypothermia can be avoided by conductive warming methods [8, 9] or forced-air warming [911]. Forced-air warming is an accepted method for preventing hypothermia in surgical patients [12] because of its well documented efficacy, [1315] low costs, and ease of use. However, forced-air warming alone is not sufficient to prevent hypothermia for every operative procedure, [1618] especially when it is used without prewarming [19]. Therefore, we compared prewarming with forced-air to no prewarming in patients undergoing TAVI-TA.


After approval of our institutional review board we compared two methods of thermal management during TAVI-TA and their effects on the course of core temperature and time of postoperative ventilatory assist in this exploratory, observational study.

Patients were premedicated with a benzodiazepine, and had a balanced anesthesia with sevoflurane (1.0-1.2 MAC) and sufentanil. The trachea was intubated and ventilation was set to give normal end-tidal CO2. Inotropes and vasopressors were administered intraoperatively to maintain stable hemodynamics, if required. Patients were defined to be hemodynamically stable if their blood pressure was ± 15% of the initial blood pressure, if they developed no tachycardia (heart rate ≤ 90 bpm), and needed only moderate inotropes or vasopressors.

After the procedure, patients were transferred to the intensive care unit (ICU). They were extubated in the operating room (OR) if hemodynamically stable, and core temperature was above 35.5°C. If these criteria were not met, they remained intubated and ventilated, and were rewarmed and weaned from the ventilator in the ICU using our standard criteria for extubation (paO2 > 100 mmHg at FiO2 = 0.4, PEEP 5 mmHg, bladder temperature ≥ 35.5°C, patient hemodynamically stable).

Initial core temperature was taken with an infrared tympanic thermometer on the awake patient before induction of anesthesia. Intra- and postoperative core temperature was monitored with a thermistor-tipped Foley catheter after induction of anesthesia and recorded. Normothermia was defined as core temperature ≥ 36.0°C.

Standard thermal management (STM) consisted of an intraoperatively circulating hot water blanket under the patient, intraoperatively forced-air warming with a lower body blanket and warmed infused fluids.

The results of the first 19 patients managed with the standard method (STM) were considered clinically inadequate in regard to the thermal management. An intensified thermal management (ITM) was therefore implemented and a further 20 patients were measured. In ITM, initial core temperature was taken with an infrared tympanic thermometer before active warming with forced-air of the awake patient was started. Active warming was then started and continued throughout the induction phase of anesthesia. The time from the start of prewarming to scrubbing was 27 ± 18 min. During the operation we used a circulating hot water blanket under the patient, forced-air warming with a lower body blanket and warmed infused fluids.

Endpoints of the study were incidence of core temperature below 36.0°C, temperature at end of procedure, eligibility for extubation in the OR, and duration of mechanical ventilation.

After testing for normal distribution with Shapiro-Wilks test, data were analyzed with Student's t test, Mann-Whitney-U-test or repeated measure analysis of variance (ANOVA) with post hoc test, as appropriate. Categorical data were analyzed with Fisher's exact test. All normally distributed data are given as mean ± standard deviation. Not normally distributed data are given as median and interquartile range (IQR). A p < 0.05 was considered statistically significant.

A planned follow-up, prospective, randomized comparison was not given approval due to the prima facie superiority of the intensified thermal management regimen shown in our data.


Demographic data and scores did not differ between the two groups (Table 1). There was no significant difference in the initial core temperature before induction of anesthesia (STM 36.0 ± 0.6°C vs. ITM 35.9 ± 0.4°C; p = 0.66), but ITM-patients had a higher core temperature before scrubbing (STM 36.2 ± 0.6°C vs. 36.6 ± 0.3°C; p = 0.008). Length of scrubbing and draping time were similar in both groups (STM 36.4 ± 12.5 min vs. ITM 36.4 ± 13.4 min; p = 0.99). Procedure time did not differ between both groups (STM 80 ± 21 min vs. ITM 74 ± 16 min; p = 0.329). ITM-patients had a significantly higher core temperature 60 and 120 minutes after induction of anesthesia and during the procedure (figure 1). On ICU admission, ITM-patients had a significantly higher core temperature (36.4 ± 0.7°C) compared to STM-patients (35.5 ± 0.9°C; p = 0.001). The incidence of hypothermia upon ICU admission was significantly higher in the STM group (13/19 vs. 5/20, p = 0.0077). These patients also needed longer to recover from hypothermia (median, IQR): STM 150 (0-300) min vs. ITM 0 (0-15) min, p = 0.003.

Table 1 Demographics and results
Figure 1
figure 1

Core body temperature before induction of anesthesia, during anesthesia, and during the first 300 min after admission to ICU.

In the STM group, 13 of 19 patients could not be extubated in the OR because core temperature was below 35.5°C. In the ITM group, 18 of 20 patients could be extubated in the OR (p = 0.0002). The STM-patients also needed longer mechanical ventilation on the ICU (median, IQR): STM 4.1 (0-7.5) h vs. ITM 0 (0-0) h, p = 0.001.


Aortic valve surgery due to aortic stenosis is one of the most common cardiac procedures and an increasing number of patients with severe comorbidities are treated with transcatheter aortic valve implantation via the transapical approach (TAVI-TA) to avoid the use of cardiopulmonary bypass (CPB). During off-pump coronary artery bypass surgery (OPCAB) maintaining normothermia is challenging, as the absence of CPB also removes the opportunity to rewarm the patient on bypass [20]. This is also true for TAVI-TA.

Hypothermia after cardiac surgery is associated with coagulopathy, increased blood loss and more transfusions of packed red blood cells [7]. It is also associated with a higher release of troponin [6], prolonged mechanical ventilation, ICU and hospital length of stay and a significantly greater mortality [7, 21].

In this study standard thermal management using intraoperatively a circulating hot water blanket under the patient, forced-air warming with a lower body blanket and warmed infused fluids was insufficient to maintain normothermia. Instead we observed a drop in core temperature throughout anesthesia and surgery.

Hypothermia is common during anesthesia and surgery. Practically all anesthetics and narcotics affect thermoregulation and therefore induction of anesthesia leads to redistribution of heat from the warm core of the body to the colder periphery [22, 23]. Without active warming measures core temperature drops in a characteristic pattern in a cold operating room. During the first hour after induction of anesthesia redistribution of heat causes an initial large drop in core temperature. During the following 3 hours core temperature linearly decreases slower due to heat loss exceeding metabolic heat production and then core temperature stops dropping [23].

Even with sufficient active intraoperative warming measures the drop of core temperature due to redistribution of heat can be observed and core temperature starts to rise again between 20 minutes to 3 hours after induction of anesthesia [810, 15, 16]. Our result of a dropping core temperature during surgery is therefore in agreement with the data given in the literature.

In contrast to the STM-patients the ITM-patients using prewarming combined with consequent intraoperative warming had a reduced incidence and degree of hypothermia. The efficacy of prewarming has been shown in several clinical studies [10, 19]. However, this result is remarkable, because several studies using forced-air warming during OPCAB surgery have failed to demonstrate efficacy, although in some of these studies patients were also actively prewarmed [5, 2427]. Therefore, several authors recommend very expensive thermal management methods like water garments [6, 24] or adhesive water mattresses [4, 28].

This difference between OPCAB surgery and TAVI-TA surgery can be explained by the fact that during OPCAB surgery large areas of the body surface are exposed to ambient room temperature during surgical skin preparation and during the procedure. Normally, both legs are exposed for vein harvesting and the thorax is opened via a sternotomy. Therefore only special cardiac surgical forced-air warming blankets can be used and these blankets cover only a very small area of the body. In contrast, during TAVI-TA less body surface is exposed and more area is left for forced-air warming. Both legs, one groin, and the right part of the thorax can be covered with forced-air warming blankets. The fact that the skin under a forced-air warming blanket is no longer an important source of heat loss [29] but a source of heat gain, changes the heat balance of the body and is responsible for the efficacy of forced-air warming.


In conclusion, patients undergoing TAVI-TA benefit from an intensified perioperative thermal management. They are less likely to become hypothermic, have a higher core temperature on ICU admission, recover faster from hypothermia, and need less mechanical ventilation. In contrast to patients undergoing OPCAB, prewarming and consequent intraoperative warming with forced-air is sufficient in patients with TAVI-TA to avoid perioperative hypothermia, and there is no need to use very expensive measures to keep these patients normothermic.


  1. Bonow RO, Carabello B, de Leon AC, Edmunds LH, Fedderly BJ, Freed MD, Gaasch WH, McKay CR, Nishimura RA, O'Gara PT: Guidelines for the management of patients with valvular heart disease: executive summary. A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee on Management of Patients with Valvular Heart Disease). Circulation. 1998, 98: 1949-1984.

    Article  CAS  PubMed  Google Scholar 

  2. Walther T, Simon P, Dewey T, Wimmer-Greinecker G, Falk V, Kasimir MT, Doss M, Borger MA, Schuler G, Glogar D: Transapical minimally invasive aortic valve implantation: multicenter experience. Circulation. 2007, 116: I240-245.

    Article  PubMed  Google Scholar 

  3. Svensson LG, Dewey T, Kapadia S, Roselli EE, Stewart A, Williams M, Anderson WN, Brown D, Leon M, Lytle B: United States feasibility study of transcatheter insertion of a stented aortic valve by the left ventricular apex. Ann Thorac Surg. 2008, 86: 46-54. 10.1016/j.athoracsur.2008.04.049. discussion 54-45

    Article  PubMed  Google Scholar 

  4. Woo YJ, Atluri P, Grand TJ, Hsu VM, Cheung A: Active thermoregulation improves outcome of off-pump coronary artery bypass. Asian Cardiovasc Thorac Ann. 2005, 13: 157-160.

    Article  PubMed  Google Scholar 

  5. Nesher N, Uretzky G, Insler S, Nataf P, Frolkis I, Pineau E, Cantoni E, Bolotin G, Vardi M, Pevni D: Thermo-wrap technology preserves normothermia better than routine thermal care in patients undergoing off-pump coronary artery bypass and is associated with lower immune response and lesser myocardial damage. J Thorac Cardiovasc Surg. 2005, 129: 1371-1378. 10.1016/j.jtcvs.2004.08.021.

    Article  PubMed  Google Scholar 

  6. Nesher N, Insler SR, Sheinberg N, Bolotin G, Kramer A, Sharony R, Paz Y, Pevni D, Loberman D, Uretzky G: A new thermoregulation system for maintaining perioperative normothermia and attenuating myocardial injury in off-pump coronary artery bypass surgery. Heart Surg Forum. 2002, 5: 373-380.

    PubMed  Google Scholar 

  7. Insler SR, O'Connor MS, Leventhal MJ, Nelson DR, Starr NJ: Association between postoperative hypothermia and adverse outcome after coronary artery bypass surgery. Ann Thorac Surg. 2000, 70: 175-181. 10.1016/S0003-4975(00)01415-6.

    Article  CAS  PubMed  Google Scholar 

  8. Matsuzaki Y, Matsukawa T, Ohki K, Yamamoto Y, Nakamura M, Oshibuchi T: Warming by resistive heating maintains perioperative normothermia as well as forced air heating. Br J Anaesth. 2003, 90: 689-691. 10.1093/bja/aeg106.

    Article  CAS  PubMed  Google Scholar 

  9. Kurz A, Sessler DI, Lenhardt R: Perioperative normothermia to reduce the incidence of surgical-wound infection and shorten hospitalization. Study of Wound Infection and Temperature Group. N Engl J Med. 1996, 334: 1209-1215. 10.1056/NEJM199605093341901.

    Article  CAS  PubMed  Google Scholar 

  10. Bock M, Muller J, Bach A, Bohrer H, Martin E, Motsch J: Effects of preinduction and intraoperative warming during major laparotomy. Br J Anaesth. 1998, 80: 159-163.

    Article  CAS  PubMed  Google Scholar 

  11. Ng SF, Oo CS, Loh KH, Lim PY, Chan YH, Ong BC: A comparative study of three warming interventions to determine the most effective in maintaining perioperative normothermia. Anesth Analg. 2003, 96: 171-176.

    PubMed  Google Scholar 

  12. Torossian A: Survey on intraoperative temperature management in Europe. Eur J Anaesthesiol. 2007, 24: 668-675. 10.1017/S0265021507000191.

    Article  CAS  PubMed  Google Scholar 

  13. Kurz A, Kurz M, Poeschl G, Faryniak B, Redl G, Hackl W: Forced-air warming maintains intraoperative normothermia better than circulating-water mattresses. Anesth Analg. 1993, 77: 89-95.

    CAS  PubMed  Google Scholar 

  14. Muller CM, Langenecker S, Andel H, Nantschev I, Holzenbein TJ, Zimpfer M: Forced-air warming maintains normothermia during orthotopic liver transplantation. Anaesthesia. 1995, 50: 229-232. 10.1111/j.1365-2044.1995.tb04562.x.

    Article  CAS  PubMed  Google Scholar 

  15. Leung KK, Lai A, Wu A: A randomised controlled trial of the electric heating pad vs forced-air warming for preventing hypothermia during laparotomy. Anaesthesia. 2007, 62: 605-608. 10.1111/j.1365-2044.2007.05021.x.

    Article  CAS  PubMed  Google Scholar 

  16. Leben J, Tryba M: Prevention of hypothermia during surgery. Contribution of convective heating system and warm infusion. Ann N Y Acad Sci. 1997, 813: 807-811. 10.1111/j.1749-6632.1997.tb51785.x.

    Article  CAS  PubMed  Google Scholar 

  17. Smith CE, Desai R, Glorioso V, Cooper A, Pinchak AC, Hagen KF: Preventing hypothermia: convective and intravenous fluid warming versus convective warming alone. J Clin Anesth. 1998, 10: 380-385. 10.1016/S0952-8180(98)00049-X.

    Article  CAS  PubMed  Google Scholar 

  18. Torrie JJ, Yip P, Robinson E: Comparison of forced-air warming and radiant heating during transurethral prostatic resection under spinal anaesthesia. Anaesth Intensive Care. 2005, 33: 733-738.

    CAS  PubMed  Google Scholar 

  19. Vanni SM, Braz JR, Modolo NS, Amorim RB, Rodrigues GR: Preoperative combined with intraoperative skin-surface warming avoids hypothermia caused by general anesthesia and surgery. J Clin Anesth. 2003, 15: 119-125. 10.1016/S0952-8180(02)00512-3.

    Article  PubMed  Google Scholar 

  20. Chassot PG, van der Linden P, Zaugg M, Mueller XM, Spahn DR: Off-pump coronary artery bypass surgery: physiology and anaesthetic management. Br J Anaesth. 2004, 92: 400-413. 10.1093/bja/aeh064.

    Article  PubMed  Google Scholar 

  21. Hannan EL, Samadashvili Z, Wechsler A, Jordan D, Lahey SJ, Culliford AT, Gold JP, Higgins RS, Smith CR: The relationship between perioperative temperature and adverse outcomes after off-pump coronary artery bypass graft surgery. J Thorac Cardiovasc Surg. 2010

    Google Scholar 

  22. Sessler DI: Mild perioperative hypothermia. N Engl J Med. 1997, 336: 1730-1737. 10.1056/NEJM199706123362407.

    Article  CAS  PubMed  Google Scholar 

  23. Matsukawa T, Sessler DI, Sessler AM, Schroeder M, Ozaki M, Kurz A, Cheng C: Heat flow and distribution during induction of general anesthesia. Anesthesiology. 1995, 82: 662-673. 10.1097/00000542-199503000-00008.

    Article  CAS  PubMed  Google Scholar 

  24. Zangrillo A, Pappalardo F, Talo G, Corno C, Landoni G, Scandroglio A, Rosica C, Crescenzi G: Temperature management during off-pump coronary artery bypass graft surgery: a randomized clinical trial on the efficacy of a circulating water system versus a forced-air system. J Cardiothorac Vasc Anesth. 2006, 20: 788-792. 10.1053/j.jvca.2005.04.014.

    Article  PubMed  Google Scholar 

  25. Hofer CK, Worn M, Tavakoli R, Sander L, Maloigne M, Klaghofer R, Zollinger A: Influence of body core temperature on blood loss and transfusion requirements during off-pump coronary artery bypass grafting: a comparison of 3 warming systems. J Thorac Cardiovasc Surg. 2005, 129: 838-843. 10.1016/j.jtcvs.2004.07.002.

    Article  CAS  PubMed  Google Scholar 

  26. Calcaterra D, Ricci M, Lombardi P, Katariya K, Panos A, Salerno TA: Reduction of postoperative hypothermia with a new warming device: a prospective randomized study in off-pump coronary artery surgery. J Cardiovasc Surg (Torino). 2009, 50: 813-817.

    CAS  Google Scholar 

  27. Kim JY, Shinn H, Oh YJ, Hong YW, Kwak HJ, Kwak YL: The effect of skin surface warming during anesthesia preparation on preventing redistribution hypothermia in the early operative period of off-pump coronary artery bypass surgery. Eur J Cardiothorac Surg. 2006, 29: 343-347. 10.1016/j.ejcts.2005.12.020.

    Article  PubMed  Google Scholar 

  28. Vassiliades TA, Nielsen JL, Lonquist JL: Evaluation of a new temperature management system during off-pump coronary artery bypass. Interact Cardiovasc Thorac Surg. 2003, 2: 454-457. 10.1016/S1569-9293(03)00112-9.

    Article  PubMed  Google Scholar 

  29. Brauer A, English MJ, Steinmetz N, Lorenz N, Perl T, Braun U, Weyland W: Comparison of forced-air warming systems with upper body blankets using a copper manikin of the human body. Acta Anaesthesiol Scand. 2002, 46: 965-972. 10.1034/j.1399-6576.2002.460807.x.

    Article  CAS  PubMed  Google Scholar 

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Correspondence to Ivo F. Brandes.

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Competing interests

RS is proctor for Edwards Lifesciences.

AB has acted as consultant for LMA Deutschland GmbH and 3 M Deutschland GmbH.

Authors IFB, MJ, AFP, and MQ do not have any competing interests.

Authors' contributions

IFB participated in designing the study, carried out the experimental work, data analysis, statistical evaluation, and drafted the manuscript. MJ participated in designing the study, and carried out the experimental work. AFP participated in the data analysis and preparation of the manuscript. RS performed the surgeries and participated in the manuscript preparation. MQ participated in the manuscript preparation. AB participated in designing the study, data analysis, and participated in the manuscript preparation. All authors read and approved the manuscript.

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Brandes, I.F., Jipp, M., Popov, A.F. et al. Intensified thermal management for patients undergoing transcatheter aortic valve implantation (TAVI). J Cardiothorac Surg 6, 117 (2011).

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