Assessment of the efficiency of warming devices during neonatal surgery


This study assessed the relative efficiency of different warming devices (surgical sheets covering the body and a tubegauze on the head, forced-air warming, warming mattress) commonly used to prevent body hypothermia during neonatal surgery. Dry heat losses were measured from a thermal manikin, which simulated a low-birth-weight neonate of 1,800 g. The manikin’s surface temperatures (35.8°C) corresponded to those of neonates nursed in closed incubators. Experiments were performed in a climatic chamber at an ambient temperature of 30°C, as commonly found in operating theatres. The supine manikin was naked or covered with operative sheets with a 5×5 cm aperture over the abdomen. Its head could be covered by a tubegauze. Additional warming was provided by conduction through a warming mattress (surface temperature, 39°C) and/or by convection (Bair Hugger, forced-air temperature 38°C). Covering the manikin with surgical sheets decreased the dry heat loss by 10.4 W. Additional forced-air warming was more efficient than the warming mattress to reduce the total dry heat loss (6.8 W vs 2.1 W). Heat losses were reduced by 7.9 W when combining the warming mattress and Bair Hugger. The heat loss from the head of the covered manikin was reduced from 4.5 W to 3.9 W when the head was covered with the tubegauze. Our data indicate that forced-air warming is more effective than conductive warming in preventing neonatal hypothermia during abdominal operations.

This is a preview of subscription content, access via your institution.

Fig. 1
Fig. 2


  1. Asaga T, Komatsu H, Chujo K, Ueki M, Yokono S, Ogli K (1997) Efficacy of ring-shape cover in active skin surface in neonates: a retrospective comparative study with conventional methods. Masui 46:1362–1367

    CAS  PubMed  Google Scholar 

  2. Brauer A, English MJ, Steinmets, Lorenz N, Perl T, Braun U, Weyland W (2002) Comparison of forced-air warming systems with upper body blankets using a copper manikin of the human body. Acta Anaesthesiol Scand 46:965–972

    Article  CAS  PubMed  Google Scholar 

  3. Elabbassi EB, Bach V, Makki M, Delanaud S, Telliez F, Léké A, Libert JP (2001) Measurement of dry heat exchanges in the newborn from a thermal mannequin: influence of body position and clothing in the sudden infant death syndrome. J Appl Physiol 91:51–56

    CAS  PubMed  Google Scholar 

  4. Elabbassi EB, Chardon K, Telliez F, Bach V, Libert JP (2002) Influence of head position on thermal stress in newborns: simulation using a thermal mannequin. J Appl Physiol 93:1275–1279

    PubMed  Google Scholar 

  5. Hynson JM, Sessler DI (1992) Intraoperative warming therapies: a comparison of three devices. J Clin Anesth 4:194–199

    Article  CAS  PubMed  Google Scholar 

  6. Komatsu H, Chujo K, Ogli K (1996) Forced-air warning system for perioperative use in neonates. Paediatr Anaesth 6:427–428

    Article  CAS  PubMed  Google Scholar 

  7. Kurz A, Kurz M, Poeschlo G, Faryniak B, Redl G, Hackl W (1993) Forced-air warning maintains intraoperative normothermia better than circulating-water mattresses. Anesth Analg 77:89–95

    CAS  PubMed  Google Scholar 

  8. Lennon RL, Hosking MP, Conover MA, Perkins WJ (1990) Evaluation of a forced-air system for warming hypothermic postoperative patients. Anesth Analg 70:424–427

    CAS  PubMed  Google Scholar 

  9. Lewis RB, Shaw A, Etchelles H (1973) Contact mattress to prevent heat loss in neonatal and paediatric surgery. Br J Anaesth 45:919–922

    CAS  PubMed  Google Scholar 

  10. Russell SH, Freeman JW (1995) Prevention of hypothermia during orthotopic liver transplantation: comparison of three different intraoperative warning methods. Br J Anaesth 74:415–418

    CAS  PubMed  Google Scholar 

  11. Sarman I (1992) Thermal responses and heart rates of low-birth-weight premature babies during daily care on a heated water-filled mattress. Acta Paediatr 81:15–20

    CAS  PubMed  Google Scholar 

  12. Sarman I, Bolin D, Holmer I, Tunell R (1992) Assessment of thermal conditions in neonatal care: use of a manikin of premature body size. Am J Perinatol 9:239–246

    CAS  PubMed  Google Scholar 

  13. Schlunzen L, Lundbol Vestergaard A, Moller-Nielsen I, Pedersen J, Hjortholm K, Sloth E (1998) Convective warming blankets improve peroperative heat preservation in congenital heart surgery. Paediatr Anaesth 8:397–401

    Article  CAS  PubMed  Google Scholar 

  14. Tollofsrud SG, Gundersen Y, Andersen R (1984) Peroperative hypothermia. Acta Anaesthesiol Scand 28:511–515

    CAS  PubMed  Google Scholar 

Download references


The authors thank the Regional Council of Picardy and the French Ministry of Research who supported this study.

Author information



Corresponding author

Correspondence to Véronique Bach.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Buisson, P., Bach, V., Elabbassi, E.B. et al. Assessment of the efficiency of warming devices during neonatal surgery. Eur J Appl Physiol 92, 694–697 (2004).

Download citation


  • Manikin
  • Neonate
  • Heat exchange
  • Warming device
  • Surgery