Table 3.
Effects of warmed, humidified carbon dioxide on postoperative pain in humans
| Study | Study type | Humans/animals | Operation | Device used | Study group |
Control group |
Results | Method of measuring pain | ||
|---|---|---|---|---|---|---|---|---|---|---|
| Treatment | No. | Treatment | No. | |||||||
| Nguyen et al. 2002 [30] | RCT | Humans | Lap Nissen fundo-plication | Insuflow device (Lexion Medical, St. Paul, MN, USA) | Heated + humidified CO2 gas + warming blanket | 10 | Warming blanket | 10 | No significant difference | VAS |
| Hamza et al. 2005 [29] | RCT | Humans | Lap Roux-en-Y gastric bypass | Insuflow device (Lexion Medical) | Heated + humidified CO2 gas | 23 | Room temperature gas | 21 | Maximum VRS and morphine consumption significantly lower in study group | 11-point VRS |
| Davis et al. 2006 [22] | RCT | Humans | Lap Roux-en-Y gastric bypass | Control- standard CO2 | Group 1-heated CO2 | 33 (11 each group) | Standard CO2 | 11 | No difference in postoperative pain | VAS |
| Group 1- heated insufflator tube set (Stryker) | Group 2-humidified CO2 | |||||||||
| Group 2,3- Insuflow (MR 860, Fisher & Paykel Healthcare, Auckland, New Zealand) | Group 3-heated+ humidified CO2 | |||||||||
| Sammour et al. 2010 [11] | RCT | Humans | Elective laparoscopic colonic resections | Insuflow (MR 860, Fisher & Paykel Healthcare) | Warmed (37°C) + humidified (98% RH) CO2 | 41 | Standard CO2 (19°C, 0% RH) | 41 | No difference in postoperative pain | (1) VAS |
| (2) MEDD | ||||||||||
| Mouton et al. 1999 [33] | RCT | Humans | Elective laparoscopic cholecystectomy | Modified LINS-1000 Insufflator (Cook Medical Technology, Queensland, Australia) | Warmed (37°C) + humidified (90% RH) CO2 | 20 | Standard CO2 (21°C, 0% RH) | 20 | Humidified + warmed CO2 group had significantly less postoperative pain at 6 hours, at 1st, 2nd, 3rd day postoperatively and on follow-up on day 10 | Analogue pain score |
| Mean time to return to normal activity was significantly lower in warmed, humidified group (5.9 days vs. 10.9 days) | ||||||||||
| Farley et al. 2004 [23] | RCT | Humans | Elective laparoscopic cholecystectomy | Insuflow device (Lexion Medical) | Warmed (35°C), humidified (95% RH) CO2 | 49 | Standard CO2 | 52 | No difference in postoperative pain during admission | (1) Likert Scale (010) |
| However, significant difference in pain on follow-up at week 2 (Likert Scale 1.0 vs. 0.3, P = 0.02) | (2) Morphine Equivalent Score (use of analgesia) | |||||||||
| Saad et al. 2000 [34] | RCT | Humans | Elective laparoscopic cholecystectomy | Flow Therme, (WISAP, Sauer-lach, Germany) | Warmed (37°C) CO2 | 10 | Standard (21°C) CO2 | 10 | No difference in postop pain (visual analogue score + analgesia usage) | (1) VAS |
| (2) Postoperative ibuprofen usage | ||||||||||
| Beste et al. 2006 [39] | RCT | Humans | Laparoscopic gynecological procedures: tubal ligation, salpingo-oo-phorectomy, cystectomy, ablation of endometriosis, adhesiolysis, che-mopertubation | Insuflow device (Lexion Medical) | Warmed, humidified CO2 | 47 | Warmed, dry CO2 | 42 | Humidified CO2 reduced postoperative pain and requirements for analgesia | Total morphine equivalent |
| Kissler et al. 2004 [40] | RCT | Humans | Laparoscopic gynecological procedures | Laparo-CO2-pneu 2232 (Wolf, Knit-tlingen, Germany) | Warmed, humidified CO2 | 30 | Cold, dry CO2 | - | Significant differences in postoperative pain and analgesia requirements | (1) Total analgesia requirement |
| Warmed, dry CO2 | 30 | 30 | Non-significant tendency towards less pain and higher patient satisfaction in patients who received cold, dry CO2 | (2) VAS | ||||||
| (3) Patient satisfaction | ||||||||||
| Manwaring et al. 2008 [25] | RCT | Humans | Laparoscopic gynecological procedures | Insuflow (MR 860, Fisher & Paykel Healthcare) | Heated (37°C), humidified (100% RH) CO2 | 30 | Cold, dry CO2 | 30 | No difference in postoperative pain or analgesia requirements | VAS |
| Champion and Williams 2006 [36] | RCT | Humans | Laparoscopic Roux-en-Y gastric bypass | Insuflow device (Lexion Medical) | Heated (35°C), humidified (95% RH) CO2 | 25 | Cold, dry CO2 | 25 | No difference in analgesia requirement or abdominal pain; significant difference in shoulder pain at 18 hours (but not at 6, 12, 24, or 48 hours) | VAS |
| Yu et al. 2013 [26] | RCT | Humans | Laparoscopic appendectomy | Insuflow (MR 860, Fisher & Paykel Healthcare) | Heated (37°C), humidified (98% RH) CO2 | 97 | Cold (20-21°C), dry (0% RH) CO2 | 98 | No difference in quantity of analgesia required | (1) MEDD |
| No difference in pain on visual analogue score | (2) VAS | |||||||||
| Savel et al. 2005 [32] | RCT | Humans | Laparoscopic Roux-en-Y gastric bypass | Insuflow device (Lexion Medical) | Heated (35°C), humidified (95% RH) CO2 | 15 | Cold, dry CO2 | 15 | No difference in quantity of morphine required postoperatively | (1) Total morphine use |
| No difference in visual analogue score | (2) VAS | |||||||||
| Klugsberger et al. 2014 [27] | RCT | Humans | Laparoscopic cholecystectomy | Optitherm device ptorz, Tuttlingen, Germany) | Heated, humidified CO2 | 81 | Cold, dry CO2 | 67 | Lower visual analogue score in the heated, humidified CO2 group at postoperative day 0 | (1) Total analgesia requirement |
| No difference in total analgesia required | (2) VAS | |||||||||
| Herrmann and De Wilde 2015 [28] | RCT | Humans | Laparoscopic assisted vaginal hysterectomy | Insuflow (MR 860, Fisher & Paykel Healthcare) | Heated (37°C), humidified (98% RH) CO2 | 48 | Cold (20-21°C), dry (0% RH) CO2 | 49 | Lower total morphine consumption in warmed, humidified CO2 group (P = 0.02) | (1) Total morphine consumption |
| (2) VAS | ||||||||||
| Benavides et al. 2009 [41] | RCT | Humans | Laparoscopic gastric banding | Insuflow device (Lexion Medical) | Heated (35°C), humidified (95% RH) CO2 | 38 | Cold, dry CO2 | 35 | Significantly less postoperative pain in warmed, humidified CO2 group than in the cold, dry CO2 and heated, dry CO2 groups (P < 0.01, P < 0.05) | MEDD |
| Heated, dry CO2 | 40 | |||||||||
RCT, randomized controlled trial; RH, relative humidity; VAS, visual analogue score; MEDD, morphine equivalent daily dose; VRS, verbal rating scale.