RESUMEN
BACKGROUND: Intra-abdominal hypertension due to surgical position increases bleeding at the surgical site. In this study, we evaluated the impact of prone and jackknife position on intra-abdominal pressure (IAP), lung mechanics, blood loss at the surgical site, and duration of the surgical procedure on lumbar disc operations. METHODS: Forty patients operated for single-space lumber disc herniation were included in our study. All patients were ASA I-II and 18 to 70 years old. Patients who had undergone previous spinal surgery, were on anticoagulant or anti-aggregant therapy, had hypertension, cardiac, respiratory, liver, or renal disorders, and were obese (Body Mass Index >35 kg/m²) were excluded. Patients were randomly assigned to either the prone or the jackknife position for surgery. Differences in lung mechanics, IAP, and surgical-site blood loss were calculated in both patient groups. Changes in pulmonary and abdominal pressure levels were measured both in face-up and down positions. RESULTS: Bleeding at the surgical site (prone: 180.0±100.0 mL, jackknife: 100.0±63.6 mL, P=0.018) and IAP (prone: 11.0±3.0 mm Hg, jackknife: 8.0±2.0 mm Hg, P=0.006) were significantly reduced when patients were in the jackknife position. Operating time was approximately 40 minutes shorter in the jackknife position group, although this difference was not significant. CONCLUSIONS: The jackknife position causes less IAP elevation and less surgical site bleeding compared with the prone position. The jackknife position is the preferred choice for single-level lumbar disc surgery in healthy, nonobese patients.