Laparoscopic surgery and ergonomics: It’s time to think of ourselves as well

Laparoscopic surgery has brought many benefits to patients. The reduction of pain, the shorter recovery time and hospital stay, and the earlier restitution of normal physiological markers have been proven objectively in many well-designed clinical studies. It has also been clear from the beginning, and has been investigated thoroughly ever since that time, that minimally invasive techniques can also cause harm to patients if they are applied indiscriminately [6]. However, the fact that laparoscopic surgery can also harm laparoscopic surgeons was only recognized somewhat later, and this phenomenon is now being investigated worldwide. The disadvantages of laparoscopic procedures are mainly due to the nonergonomic design of the surgical instruments and the out dated environment of the operating theater. As laparoscopic surgery became more advanced and complex, the duration of the procedures expanded and, in proportion, so did the levels of mental and physical stress imposed on the surgical team. Yet so far, no significant changes have been made to the operating room, which was originally designed for conventional operations. Ergonomics, a relatively new science, first gained wide popularity in the field of industrial engineering. Experts began to notice that when workers do their jobs under nonergonomical circumstances they become stressed and fatigued, which leads to a drop in quality and productivity. As the advertising industry began to tout the ‘‘ergonomic design’’ of various cars and household utensils, ergonomics was viewed as a serious factor influencing the sales of such products. Today, enormous sums of money are earmarked for ergonomical research into industrial design. In turn, new industrial software tools have been developed to assess the ergonomic features of new products. These tools are designed to measure the posture and movement of the human body very accurately, without using any markers [17]. Unfortunately, medicine did not get in on the ground floor of these ergonomic developments, because productivity and quality in this area cannot be connected as directly to ergonomics as they can in industry, and the profit gained from ergonomic reorganization is difficult to quantify in financial terms. Thus, it has been reported that the main reason for choosing a particular instrument is its cost–quality ratio and not its ergonomic design [18]. However, thanks to the concerted efforts of surgeons and medical staff, the assessment of the ergonomic aspects of laparoscopic surgery is now under way. We already have many objective data on the problems that arise in the course of everyday practice, and some attempts have been made to alter the operating environment accordingly [10]. During laparoscopic operations, surgeons suffer from high levels of mental and physical stress. After a certain time— 4 h—the so-called surgical fatigue syndrome sets in. This syndrome is characterized by mental exhaustion, reduced dexterity, and a reduced capacity for good judgment [6]. Mental stress is caused by numerous factors. The view of the operative situation is displayed on a monitor that is widely separated from the field of action [9], so the surgeon has to overcome the natural instinct to direct the eyes to the activity of the hands. The two-dimensional viewing of a three-dimensional field has to be interpreted and synchronized to instrument movement. The surgeon also has to adapt to the fact that the tip of the instrument is moving in a direction opposite to the handle—the socalled fulcrum effect [5, 8]. In addition to performing the operation, the surgeon has to constantly monitor the different devices used during the procedure. Although it is not easy to measure mental stress, there are some data on skin conductance level and electro-oculogram monitoring as they relate to increased mental concentration [3]. It has been shown that mental stress can be compensated for with mental effort [5, 8], but such efforts surely lead to earlier fatigue, which can be a significant handicap during operations that last for hours. Physical stress, on the other hand, can be measured very well with objective devices. Standing in a fixed position determined by the placement of the trocars and the site of the screen(s) causes static strain to the eyes, head, neck, and spine, which translates into eye strain, neck and shoulder pain, and stiffness [2, 12]. This type of stress can be measured by the duration of the stressful postures and the rotation of the joints as compared to the characteristics of a comfortable posture, or by the force plate measurement of the feet, which indicates the characteristic position of the trunk [1]. In order to pivot the instruments around the trocars, which are fixed to the abdominal wall, increased muscle activity and Letters to the editor