CHANGES IN END-TIDAL CARBON-DIOXIDE DURING GYNECOLOGIC LAPAROSCOPY - SPONTANEOUS VERSUS CONTROLLED VENTILATION

Study Objective: To study the changes in PETCO2 during spontaneous and controlled ventilation in patients undergoing gynecologic laparoscopy . Design: Randomized, unblinded study. Setting: Department of Gynecolo gy, University Hospital, Linkoping; Sweden; Central Hospital, Norrkopi ng, Sweden. Patients: Forty healthy patients undergoing gynecologic la paroscopy. Interventions: Patients were divided into 4 groups: Group 1 breathed spontaneously via an endotracheal tube, while the other thre e groups underwent controlled ventilation to an initial PETCO2 of 3 kP a (22 mmHg) (Group 2), 4 KPa (30 mmHg) (Group 3), or 5 kPa (37 mmHg) ( Croup 4). Measurements and Main Results: PETCO2 levels were measured a t fixed time intervals. Arterial blood gas analyses were done to compa re the difference between PETCO2 and PaCO. In Group 1, PETCO2 increase d soon after insufflation and remained above G kPa (44 mmHg) throughou t the procedure. In Groups 2, 3, and 4, PETCO2 also rose after insuffl ation, and an initial PETCO2 of 4 KPa (30 mmHg) was ideal, as all PETC O2 values were less than 5.5 kPa (41 mmHg). Occasional episodes of arr hythmia were seen in Group 1. However no major adverse effects were ob served in any of the groups. Conclusions: In view of the high PETCO2 l evels, spontaneous breathing should be avoided during gynecologic lapa roscopy, and ventilation to an initial PETCO2 of 4 kPa (30 mmHg) is re commended during controlled ventilation.