Department of Anesthesiology and Intensive Care Unit, Henri Mondor Hospital, 51 avenue Marechal de Lattre de Tassigny, 94010 Creteil, France
*Corresponding author. E-mail: philippe.duvaldestin@hmn.ap-hop-paris.fr
Accepted for publication: July 9, 2003
![]() |
Abstract |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
Methods. We measured carbon dioxide elimination with a metabolic monitor in 30 anaesthetized patients with controlled ventilation, undergoing retroperitoneoscopy (n=10), laparoscopy (n=10) or orthopaedic surgery (n=10).
Results. Carbon dioxide production increased by 38, 46 and 63% at 30, 60 and 90 min after insufflation (P<0.01) in patients having retroperitoneoscopy. Carbon dioxide production (mean (SD)) increased from 92 (21) to 150 (43) ml min1 m2 6090 min after insufflation and remained increased after the end of insufflation. During laparoscopy, V·CO2 increased less (by 15%) (P<0.05 compared with retroperitoneoscopy) and remained steady throughout the procedure.
Conclusion. Retroperitoneal carbon dioxide insufflation causes more carbon dioxide absorption than intraperitoneal insufflation, and controlled ventilation should be increased if hypercapnia should be avoided.
Br J Anaesth 2003; 91: 7936
Keywords: carbon dioxide, measurement; surgery, renal; surgery, retroperitoneoscopy
![]() |
Introduction |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
![]() |
Methods |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
Statistical analysis
Data are expressed as mean (SD) for absolute values of V·O2, V·CO2 and also as percentage of the variation in V·CO2 at T0. Differences between the three groups were studied using two-way analysis of variance (ANOVA) with repeated measures (Statview 5.0 package, SAS Institute Inc., Cary, NC, USA). If there was a significant time x group interaction, a Scheffé ANOVA post hoc test was used to study differences between groups at each time of measurement. To compare data in each group, one-way ANOVA with repeated measures was performed. P<0.05 was considered significant. The sample size was calculated on the basis of carbon dioxide production between 30 and 60 min. We chose arbitrarily to detect a difference of 25 ml min1 m2 in carbon dioxide between retroperitoneal and intraperitoneal laparoscopy groups with a standard deviation of 18 ml min1 m2.9
![]() |
Results |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
|
|
|
|
![]() |
Discussion |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
We measured the systemic absorption of carbon dioxide with a metabolic monitor connected to the ventilator. This non-invasive equipment is designed to measure carbon dioxide production and oxygen consumption. In the study conditions, the amount of carbon dioxide recovered from the lungs comes from metabolism and from carbon dioxide absorbed from the site of insufflation. The simultaneous measurement of oxygen consumption indicates how much of the change in pulmonary carbon dioxide lung output is the result of metabolism and how much is due to carbon dioxide absorption. The respiratory quotient also indicates the fraction of carbon dioxide production that is from absorption of the insufflated gas. In previous studies of patients undergoing renal surgery under retroperitoneoscopy, carbon dioxide absorption was calculated from the values of the minute ventilation volume and measurements of end-tidal carbon dioxide concentration.5 6 This method is inherently flawed because the integral of exhaled flow multiplied by the instantaneous carbon dioxide concentration is needed for accurate measurement of the quantity of carbon dioxide expired. In addition, expiratory flows and volumes measured from anaesthesia apparatus are rather inaccurate.10 In the present study, whole-body oxygen consumption remained stable during the different periods of the anaesthetic and surgical procedures and was similar for each group of patients, suggesting that the part of carbon dioxide production related to whole-body metabolism remained stable throughout the study and between patient groups. In addition, end-tidal carbon dioxide was maintained at its physiological value throughout the study. Therefore the increase in carbon dioxide production or respiratory quotient could be directly related to the absorption of carbon dioxide from the site of insufflation. In the patients undergoing peritoneal laparoscopy, the increase in carbon dioxide production was small (about 1015% of the basal value) and was similar in magnitude to the value reported in previous studies during laparoscopic cholecystectomy.9 11 At the end of exsufflation, carbon dioxide production returned to its basal value during peritoneal laparoscopy, suggesting that no persistence of carbon dioxide occurred. In the patients undergoing retroperitoneoscopy, carbon dioxide absorption accounted for 4060% of the basal value, with a tendency to a steady increase throughout the period of insufflation. Similar findings were observed during retroperitoneal insufflation in the pelvis by Mullet et al.,9 who suggested that continued dissection of the retroperitoneal space could increase the area of contact with carbon dioxide. In patients undergoing retroperitoneoscopy, large interindividual variations in carbon dioxide production were observed: in some patients carbon dioxide production increased to 200% of the control value. In these patients end-tidal carbon dioxide could be maintained within normal values by adjustment of the ventilator; however, this could change lung volumes and dead space, and this could affect the alveolo-arterial carbon dioxide difference. This was not seen in the present study. This observation supports previous studies in which the alveolo-arterial gradient did not increase in patients undergoing laparoscopic cholecystectomy under general anaesthesia with controlled ventilation.11 12 In contrast to peritoneal insufflation, in which carbon dioxide output immediately fell at cessation of insufflation, the carbon dioxide output remained high after retroperitoneoscopy. Persistent accumulation of carbon dioxide during the early postoperative period should be considered in the postoperative care of such patients.
In conclusion, retroperitoneal carbon dioxide insufflation allows much greater absorption of carbon dioxide than during intraperitoneal insufflation. Carbon dioxide absorption increases with time during retroperitoneal insufflation and carbon dioxide absorption persists after exsufflation.
![]() |
References |
---|
![]() ![]() ![]() ![]() ![]() ![]() ![]() |
---|
2 Joris J, Ledoux D, Honore P, Lamy M. Ventilatory effects of CO2 insufflation during laparoscopic cholecystectomy. Anesthesiology 1991; 75: A121
3 Baird JE, Granger R, Klein R, et al. The effects of peritoneal carbon dioxide insufflation on hemodynamics and arterial carbon dioxide. Am J Surg 1999; 177: 1646[CrossRef][ISI][Medline]
4 Wolf JS, Carrier S, Stoller ML. Intraperitoneal versus extraperitoneal insufflation of carbon dioxide as for laparoscopy. J Endourol 1995; 9: 636[ISI][Medline]
5 Ng CS, Gill IS, Sung GT, Whalley DG, Graham R, Schweizer D. Retroperitoneoscopic surgery is not associated with increased carbon dioxide absorption. J Urol 1999; 162: 126872[ISI][Medline]
6 Wolf JS Jr, Monk TG, McDougall EM, et al. The extraperitoneal approach and subcutaneous emphysema are associated with greater absorption of carbon dioxide during laparoscopic renal surgery. J Urol 1995; 154: 95963[ISI][Medline]
7 Bracco D,Chiolero R, Pasche O, Revelly JP. Failure in measuring gas exchange in the ICU. Chest 1995; 107: 140610
8 Tissot S, Delafosse B, Bertrand O, Bouffard Y, Viale JP, Annat G. Clinical validation of the Deltatrac monitoring system in mechanically ventilated patients. Intensive Care Med 1995; 21: 14953[ISI][Medline]
9 Mullet CE, Viale JP, Sagnard PE, et al. Pulmonary CO2 elimination during surgical procedures using intra- or extraperitoneal CO2 insufflation. Anesth Analg 1993; 76: 6226[Abstract]
10 Liu N, Beydon L, Bach B, et al. A study of 11 ventilators for anesthesia: laboratory testing. Ann Fr Anesth Reanim 1992; 11: 5028[ISI][Medline]
11 Bures E, Fusciardi J, Lanquetot H, et al. Ventilatory effects of laparoscopic cholecystectomy. Acta Anaesthesiol Scand 1996; 40: 56673[ISI][Medline]
12 Girardis M, Da Broi U, Antoutto G, Pasetto A. The effect of laparoscopic cholecystectomy on cardiovascular function and pulmonary gas exchange. Anesth Analg 1996; 39: 61732