Are pulse oximetry and end-tidal carbon dioxide tension monitoring reliable during laparoscopic surgery?
Cardiorespiratory changes induced by pneumoperitoneum and head-up tilt may generate alveolar ventilation to perfusion ratio changes and increased systemic vascular resistances. The reliability of end-tidal carbon dioxide tension and pulse oximetry in predicting arterial carbon dioxide partial pressure and arterial oxygen saturation may therefore be affected. The 35 ASA 1-2 patients in this study comprised 12 men and 23 women aged 48 (SD 17) years and weighing 71 (SD 14) kg. Twenty-nine were to undergo upper abdominal laparoscopy for cholecystectomy and six hyperselective vagotomy. Intra-abdominal pressure was 1.7 (SD 0.9) kPa and head-up tilt was 5.6 (SD 4.2) degrees. After abdominal insuflation, arterial carbon dioxide partial pressure significantly increased (p < 0.05). However, the arterial carbon dioxide partial pressure-end-tidal carbon dioxide partial pressure gradient remained constant throughout surgery. This gradient was highly correlated with arterial carbon dioxide partial pressure (p < 0.0001), but was not correlated with elapsed time, intra-abdominal pressure or head-up tilt. Arterial oxygen saturation was always greater than 95% in all patients and the arterial oxygen saturation-pulse oximetric saturation gradient was always less than or equal to +4%. In conclusion, end-tidal carbon dioxide partial pressure and pulse oximetric saturation allow reliable monitoring of arterial carbon dioxide partial pressure and arterial oxygen saturation in the absence of pre-existing cardiopulmonary disease and/or acute peroperative disturbance.
Nyarwaya
J B
JB
Département d'Anesthésie-Réanimation, Hôpital de Bicêtre, Université Paris-Sud, Le Kremlin Bicêtre, France.
Mazoit
J X
JX
Samii
K
K
D000328:Adult; D002245:Carbon Dioxide / Q000097:blood*; D017081:Cholecystectomy, Laparoscopic; D005260:Female; D006801:Humans; D010535:Laparoscopy; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative; D010092:Oximetry; D010100:Oxygen / Q000097:blood; D010313:Partial Pressure; D011187:Posture; D013990:Tidal Volume; D013997:Time Factors; D014629:Vagotomy, Proximal Gastric
D002245:Carbon Dioxide; D010100:Oxygen