It’s Not Just Another Room…

Abstract

Anesthesiologists spend much of their waking hours in one of the world’s most complex infrastructural and technological work environments, the modern operating room.1 There, they are surrounded by advanced equipment continuously monitoring patients’ physiological functions; precision anesthetic delivery systems; computerized anesthetic, hospital, and radiologic information systems; surgical instrumentation including lasers, robots, optical fiberscopes, and advanced imaging modalities; and operating room ventilation systems designed to facilitate sterile operating fields. The operating room’s complexity is said to be exceeded only by the “clean rooms” used in manufacturing microelectronic microprocessors and other such chips, where the ventilation systems are designed to prevent environmental particles and substances from interfering with the chemicals and materials used in the manufacturing process, as well as supporting the creation of silicon chips containing billions of transistors. It is said that the average surgical operating room is 3 times dirtier than the “dirtiest” clean room.2 Because of the operating room’s extremely complicated infrastructure, made even more complex by the equipment and clinical activities within, the interaction of its various structural features, mobile equipment, and human components can become problematic. Examples abound and include the combination of electrosurgical cauterization by the surgeon and oxygen administration by the anesthesiologist, which can lead to ignition of paper or cloth drapes and resulting in serious patient injury from the operating room fire.3 The design and heat generated by operating room lights and the arrangement of equipment on the floor can hamper the effectiveness of laminar flow ventilation systems designed to reduce wound contamination.4,5 Operating room lights (especially the older non–light emitting diode models) also generate much heat, making gloved, gowned, and masked surgeons uncomfortable, leading to requests to lower the ambient temperature, which in turn contributes to patient hypothermia. The connection between forced-air warmers and surgical site infections (SSIs) is this paradoxical situation, wherein the patient’s body temperature needs to be preserved but the surgeon requires personal cooling, that is among the reasons why patient-warming devices have evolved. It is in this context of the increasing awareness of the many man–machine–infrastructural interactions that occur in operating rooms that the simulation study by Belani et al.,6 on how a forced-air patient-warming system might contribute to the contamination of a sterile field, is timely. Intraoperative hypothermia is both the friend and foe of the anesthesiologist. The former occurs when hypothermia is intentionally induced for organ preservation during cardiopulmonary bypass, total circulatory arrest, post–cardiac arrest, and during neurosurgical procedures. However, most often anesthesiologists are engaged in combating its development. Since the early 1980s, the mechanisms causing hypothermia,7 its clinical consequences8,9 and methods to prevent its development,10 have been well studied. Many reports have shown the association of intraoperative hypothermia with greater blood loss and transfusion requirements; more SSIs, and along with the stress of the subsequent rewarming, increased cardiovascular complications.10,11 These studies have provided the impetus to recommendations and guidelines that routine measures be implemented to prevent unplanned intraoperative hypothermia. Furthermore, there are ongoing initiatives that propose to make maintenance of perioperative normothermia a performance-based payment condition.11–13 This emphasis on preventing unintended intraoperative hypothermia has led to the routine use of warming measures before, during, and after surgery. Historically, warm water “blankets” (even though they were mostly used underneath the patients as “mattresses”) preceded fo