Abstracts of Posters Presented at the International Anesthesia Research Society; 72nd Clinical and Scientific Congress; Orlando, FL; March 7-11, 1998: Cardiovascular Anesthesia
More procedures are being performed laparoscopically due to postoperative advantages. Laparoscopic nephrectomy requires lateral decubitus positioning with the "kidney rest" position (LD). The hemodynamic effects of LD and increases in abdominal pressure (Pab) caused by CO2 insufflation during LD have not been reported.
METHODS: After protocol approval from the University of Maryland Human Volunteers Research Committee and informed consent, 12 patients undergoing elective donor laparoscopic nephrectomy were studied. No patient had any history of cardiopulmonary disease. Anesthesia was induced with propofol (1-2 mg/kg) or thiopental (4-5 mg/kg). Paralysis was achieved and maintained with mivacurium. Patients were ventilated with 30% O2/70% N2 O and 0.4-1.0% isoflurane. The following cardiovascular variables were measured: heart rate, systolic (SBP) and diastolic (DBP) blood pressures (Spacelabs Medical, Redmond, WA) and arterial oxygen saturation (Criticare, Waukeshau. WI). Measurements were made with the patient supine immediately after induction of anesthesia/paralysis and following LD prior to surgical manipulations. Measurements were repeated in the LD position following CO2 insufflation with Pab=15 mmHg and supine following abdominal deflation at the conclusion of surgery immediately prior to anesthesia emergence. To test whether these values were significant repeated ANOVA measures were utilized.
RESULTS: SBP was elevated (p<0.05) during abdominal insufflation and after surgery compared to LD values. DBP was elevated (p<0.05) during abdominal insufflation compared to all other postures and conditions (Table 1). Heart rate was lower (p<0.05) during LD position and during insufflation. There were no changes in arterial oxygen saturation.
CONCLUSIONS: These results demonstrate that laparoscopy for nephrectomy in the LD position results in significant hemodynamic changes in healthy patients, especially during abdominal insufflation. Whether these changes may be vital if this procedure is performed in patients with cardiopulmonary disease needs to be studied.