Pacilli M, Pierro A, Kingsley C, Curry J I, Herod J, Eaton S
Department of Surgery, Institute of Child Health, Great Ormond Street Hospital for Children, London, UK.
Br J Anaesth. 2006 Aug;97(2):215-9. doi: 10.1093/bja/ael134. Epub 2006 May 23.
Carbon dioxide (CO(2)) is absorbed during pneumoperitoneum and may cause adverse haemodynamic effects. The aim of this study was to measure the elimination of exogenous CO(2) during laparoscopy in children.
Ten children [27.6 (56.5) months; mean (SD)] undergoing laparoscopic and nine [24.5 (17.3) months] undergoing open surgery were studied. Breath samples were collected at the line for end-tidal CO(2) and analysed for (13)CO(2)/(12)CO(2) ratio expressed as deltaPDB (difference from standard), by isotope-ratio mass spectrometry. The proportion of absorbed CO(2) was calculated comparing exhaled (13)CO(2)/(12)CO(2) before and during CO(2) pneumoperitoneum.
(13)CO(2)/(12)CO(2) in medical CO(2) was -32.7 (2.1) deltaPDB. (13)CO(2)/(12)CO(2) in breath of patients undergoing open procedures was -24.3 (2.4) deltaPDB at the start of operation and did not change during the operation (P > 0.2). (13)CO(2)/(12)CO(2) in breath of patients undergoing laparoscopy was -21.5 (5.4) deltaPDB at the start of insufflation, and decreased during pneumoperitoneum by 2.5 (1.6) deltaPDB, indicating absorption of exogenous CO(2). The percentage of expired CO(2) absorbed rose to 15.5 (7.7)% after 30 min of pneumoperitoneum and decreased rapidly after desufflation.
After 10 min of laparoscopy 10-20% of expired CO(2) derives from the exogenous CO(2). CO(2) absorption can be measured using a simple mass spectrometric technique.
气腹过程中二氧化碳（CO₂）被吸收，可能会引起不良血流动力学效应。本研究的目的是测量儿童腹腔镜手术期间外源性CO₂的消除情况。
对10例接受腹腔镜手术的儿童[27.6（56.5）个月；均值（标准差）]和9例接受开放手术的儿童[24.5（17.3）个月]进行研究。在呼气末CO₂监测线上采集呼气样本，并用同位素比率质谱法分析其中¹³CO₂/¹²CO₂的比率，以δPDB（与标准的差值）表示。通过比较气腹前和气腹期间呼出的¹³CO₂/¹²CO₂来计算吸收的CO₂比例。
医用CO₂中的¹³CO₂/¹²CO₂为-32.7（2.1）δPDB。接受开放手术患者在手术开始时呼气中的¹³CO₂/¹²CO₂为-24.3（2.4）δPDB，手术期间未发生变化（P>0.2）。接受腹腔镜手术患者在气腹开始时呼气中的¹³CO₂/¹²CO₂为-21.5（5.4）δPDB，气腹期间降低了2.5（1.6）δPDB，表明外源性CO₂被吸收。气腹30分钟后呼出的CO₂被吸收的百分比升至15.5（7.7）%，放气后迅速下降。
腹腔镜手术10分钟后，呼出的CO₂中有10%-20%来自外源性CO₂。可以使用简单的质谱技术测量CO₂的吸收情况。
