Scientific Studies

EFFECTS OF CO₂ GAS PROPERTIES ON POST-OPERATIVE PAIN

Heated and Humidified Insufflation During Laparoscopic Gastric Bypass Surgery: Effect on Temperature, Postoperative Pain, and Recovery Outcomes

Hamza M, Schneider B, White P, Recart A, Villegas L, Ogunnaike B, Provost D, Jones D. J Laparoendosc Adv Surg Tech 2005, 15(1) :6-12

PATIENTS  & METHODS
Fifty (50) morbidly obese patients underwent laparoscopic Rouxen-Y gastric bypass. Control group (cold dry gas, n=21) and Insuflow^®; humidifying gas conditioning group (n=23) in a randomized prospective controlled study.

RESULTS
Use of the Insuflow^®; device had 1) statistically significant higher intraoperative core body temperature, 2) no post-operative shivering, 3) less post-operative morphine analgesia, and 4) a higher quality of recovery by post-operative day two.

Reduction of Laparoscopic-Induced Hypothermia, Postoperative Pain and Recovery Room Length of Stay by Pre-Conditioning Gas with the Insuflow^® Device: A Prospective Randomized Controlled Multi-Center Study

Ott D, Reich H, Love B, McCorvey R, Toldedo A, Liu C, Syed R, Kumar K. JSLS 1998; 2:321-329

CONCLUSION
Pre-conditioning laparoscopic gas by filtering heating and hydrating with the Insuflow^®; device was significantly more effective than the currently used standard raw gas and was safe in reducing or eliminating laparoscopic induced hypothermia, shortening recovery room length of stay and reducing post-operative pain.

The Effect of Warm Humidified CO₂ on the Dissipation of Residual Gas Following Laparoscopy in Piglets

Glew P, Campher M, Pearson K, Schofield J, Davey A. J Am Assoc Gynecol Laparosc 2004, 11(2) :204-210

This is a piglet study about abdominal insufflation comparing two groups of five using either traditional cold dry or warm, humidified carbon dioxide (CO₂).

RESULTS
Radiographic gas bubble profile calculation and blood sample testing of IL-1 and TNF up to 5 hours. Residual CO₂ dissipates more rapidly when the gas is heated and humidified compared with cold and dry gas. The humidified warm gas group had “a reduction in the duration of inflammatory response as measured by TNF production.”

CONCLUSION
“Heating and humidifying CO₂ leads to faster dissipation of residual gas associated with a reduced duration of inflammation, which may contribute toward a reduction in post-laparoscopic pain. ”

Role of Heated and Humidified Intra-pertoneal Gases Using an Insuflow^®; Device During Laparoscopic Roux-en-Y Surgery – Effect on Temperature, Post-Operative Pain, and Recovery

Hamza M, Recart A, White P, Ogunnaike T, Schneider B, Provost D, Jones D. Department of Anesthesiology, Pain  Management and the Department of Surgery, University of Texas Southwestern Medical Center, Dallas, TX. Presented at the SAGES Annual Meeting 2003, Los Angeles, CA, and the IARS Meeting 2003, New Orleans, LA

ABSTRACT
The Insuflow^®; device was associated with significantly higher core body temperature after one hour of insufflation. Pain scores and opioid analgesic requirements were significantly lower in the Insuflow^®; group. The length of stay in the PACU and hospital were shorter in the Insuflow^®; group but not significantly different. The patients in the Insuflow^®; group reported a better quality of recovery on post-operative day #2.

Double Blind, Prospective, Randomized Study of Warmed Humidified CO₂ Insufflation versus Standard CO₂ for Patients Undergoing Laparoscopic Cholecystectomy

Farley D, Greenlee S, Larson D, Harrington J . Arch. Surg. 2004; 139:739-744

METHODS
A double blind, prospective, randomized study comparing patients undergoing laparoscopic cholecystectomy with cold, dry CO₂ insufflation versus warmed, humidified CO₂ (Insuflow^®;, LEXION Medical, St. Paul, MN) was performed. Main variables included patient temperature, lens fogging, post-operative pain, and narcotic requirements.

RESULTS
101 blinded patients (69 women, 32 men) undergoing laparoscopic cholecystectomy were randomized into two groups: 52 having standard CO₂ insufflation (Group A) and 49 given warmed, humidified CO₂ (Group B). Statistical differences between groups were seen with mean patient intraoperative temperature change (Group A decreased by 0.03ºC, Group B increased by 0.29ºC, p=0.01) and mean abdominal pain decreased (Likert scale 0-10) at 14 days (A=1.0, B=0.3, p=0.02).

COMMENT
The statistically significant findings were 4-fold: patients were warmer intraoperatively using the Insuflow^®; device, they harbored less shoulder pain at PACU entry, they had less abdominal pain at 2 weeks post-operatively, and they used less pain medication at 2 weeks post-operatively.

Warm and Humidified Carbon Dioxide During Laparoscopic Roux-en-Y Gastric Bypass Surgery for Morbid Obesity Decreases Post-operative Pain and Analgesic Requirement

Murray Friedman Resident Research Award, 2004 Bala S, Arabov E, Fazilov R, Lazzaro R, Macura J, Cunningham J. Department of Surgery, Division of Bariatric Surgery, Maimonides Medical Center, Brooklyn, NY

CONCLUSION
Patients who received warm and humidified carbon dioxide (Insuflow^®; device) during laparoscopic roux-en-y gastric bypass surgery for morbid obesity required significantly less post-operative analgesia than those who did not.

Complications of Microlaparoscopy and Awake Laparoscopy

Demco L . Journal of the Society of Laparoendoscopic Surgeons (2003) 7:141-145

ABSTRACT
Complications of laparoscopy are categorized into trocar insertion complications, complications resulting from image quality, and complications resulting from instrumentation. The cause of shoulder pain is focused on the drying effect of the carbon dioxide on the peritoneal cell. The low humidity results in mesothelial integrity being lost, and the basal lamina exposed. Heating and humidifying the carbon dioxide with the Insuflow^®; device to 37ºC and 95% relative humidity prior to insufflation into the peritoneal cavity maintains body temperature even during prolonged laparoscopic procedures. There is also a decrease in shoulder pain and its frequency and a decrease in post-operative pain and shortened length of stay compared to dry gas.

Decreased Incidence of Hypothermia and Peritoneal Irritation in Laparoscopic Donor Nephrectomy Using a Filter-Hydrator-Heating Device (Insuflow^®;)

Kandaswamy R, Gillingham K, Harmon J , Asolati M. Department of Surgery, University of Minnesota, Presented at SAGES 2003 Annual Meeting, Los Angeles, CA

ABSTRACT
Insuflow^®; was used in 10 laparoscopic kidney donors during a 2-month period. The data was compared with 10 contemporaneous donors without Insuflow^®; use. Length of hospital stay (3.3 vs. 3.8 days) and post-operative analgesic use measured in morphine equivalents (62 mg vs. 69 mg) were no different between groups. However, Insuflow^®; patients spent less time in the recovery room (94 vs. 140 minutes) (p=0.02), had decreased incidence of shoulder pain (0% vs. 40%) (p=0.09) and shivering (0% vs. 40%) (p=0.09). At the end of the procedure 70% of the non-Insuflow^®; patients were hypothermic compared to none in the Insuflow^®; group. The Insuflow^®; device decreases the incidence of hypothermia and shivering and may be associated with decreased peritoneal desiccation leading to decreased incidence of shoulder tip pain.

A Randomized Controlled Trial Assessing the Benefit of Humidified Insufflation Gas During Laparoscopic Surgery

Mouton W, Bessell J, Millard S, Baxter P, Maddern G. Surg Endosc (1999) 13:106-108

No adverse effects from humidification of insufflated gas. Pain significantly reduced at 6 hours, first, second and third days. In the humidified group the mean time taken to return to normal activities was significantly less; 5.9 days compared to 10.9 days in the control group – a 54% improvement.

CONCLUSION
The use of humidified insufflation gas reduces post-operative pain following laparoscopic cholecystectomy.

Optimal Warming Technique for Major Laparoscopic Surgery: Forced Air Warming or Warmed and Humidified Insufflation Gas

Hamza M, Ogunnaike B, Provost D, White P. Department of Anes thesiology and Pain Management, University of Texas Southwestern Medical Center, Dallas, Tx

CONCLUSION
The Insuflow^®; device may be a useful alternative to forced air warming devices during major laparoscopic surgery. Although less effective in maintaining core temperature than the external forced air warming device, the Insuflow^®; improved pain control and reduced the need for opioid analgesics and antiemedics in the post-operative period.

Awake Microlaparoscopy with the Insuflow^®; Device

Almeida O. JSLS (2002) 6:199-201

RESULTS
The incidence of transient shoulder pain in the Insuflow^®; group was 5% compared with 40% in the dry carbon dioxide group. No patient in the Insuflow^®; group complained of shivering, whereas 55% in the control group had shivering. Fogging of the microlaparoscope lens was decreased in the Insuflow^®; group.

CONCLUSION
Heating and humidifying the carbon dioxide gas produced fewer patient complaints of shoulder pain and shivering and decreased fogging of the microlaparoscope lens compared with procedures done with dry carbon dioxide during awake microlaparoscopic procedures.

Complications of the Laparoscopic Approach

Hill D, et. al. Bailliere’s Clinical Obstetrics and Gynecology. December 1994, Vol . 8, No. 4

Hypothermia is created by the gas reducing the well being of the patient and increasing post-operative analgesia.

The Effect of Heating and Humidifying Gas on Patients Undergoing Awake Laparoscopy

Golden Micro Endoscopic Award, 2000 Demco L. J Am Assoc Gynecol Laparosc 8(2):247-251, 2001

RESULTS
Patients exposed to CO₂ gas modified by the Insuflow^®; device had absent or dramatically reduced shoulder pain. This allowed a significant increase in surgical time to perform diagnosis and treatment due to increased patient comfort. Those women who had shoulder pain, it was transitory, less intense, and of shorter duration than in those exposed to the currently used cold, dry CO₂. Post-operative recovery time was shortened in the Insuflow^®; device group with 80% of patients leaving the hospital within 90 minutes.

CONCLUSION
Heating and humidifying CO₂ increases patient tolerance during awake laparoscopy using local anesthesia, decreases the frequency and duration of shoulder pain, shortens recovery time and improves safety of the procedure.

Pain After Laparoscopy

Mouton W, Bes sel l J , Ot ten K, Maddern G. Surg Endosc (1999) 13:445-448

Background Post-operative laparoscopic pain is a problem with as many as 80% of patients requiring opioid analgesia.

CONCLUSION
To reduce pain, use humidified gas at body temperature.

Heated and Humidified CO₂ Prevents Hypothermia, Peritoneal Injury, and Intra-Abdominal Adhesions During Prolonged Laparoscopic Insufflations.

Yuanfei Peng, Ph.D.,* Minhua Zheng, M.D., Ph.D.,*^,1 Qing Ye, Ph.D.,* Xuehua Chen, Ph.D.,† Beiqing Yu, Ph.D.,† and Bingya Liu, M.D., Ph.D.†

*Department of General Surgery, Shanghai  Minimally Invasive Surgery Center, †Institute of Digestive Surgery, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China

BACKGROUND

Insufflation with standard cold-dry CO₂ during laparoscopic surgery has been shown to predispose patients to hypothermia and peritoneal injury. This study aimed to compare the effect of prolonged cold-dry CO₂ insufflation with heated-humidified CO₂ insufflation (3-5 h) on hypothermia, peritoneal damage, and intra-abdominal adhesion formation in a rat model.

MATERIALS AND METHODS

A total of 160 Wistar rats were randomized to undergo no insufflation or insufflation with cold-dry CO₂ (21°C, <1% relative humidity) or heated-humidified CO₂ (37°C, 95% relative humidity) for 3, 4, or 5 h. Core body temperature was measured via rectum before and during insufflations. Peritoneal samples were taken at 6, 24, 48 and 96 h after treatments and analyzed with light microscopy and scanning electron microscopy. Intra-abdominal adhesions were evaluated 2 weeks later.

RESULTS

Core body temperature significantly decreased in the cold-dry group, wheras it was maintained and increased in the heated-humidified group. Scanning electron microscopy and light microscopy studies showed intense peritoneal injury in the cold-dry CO₂ group but significantly less damages in the heated-humidified group. Increased intra-abdominal adhesion formation was observed in the cold-dry CO₂ group, while no adhesions were found in the rats insufflated with heated-humidified CO₂.

CONCLUSIONS

Heated-humidified CO₂ insufflation results in significantly less hypothermia, less peritoneal damage, and decreased adhesion formation as compared with cold-dry CO₂ insufflation. Heated-humidified CO₂ may be more suitable for insufflation applications in prolonged laparoscopic surgery.

Humidified Compared with Dry, Heated Carbon Dioxide at Laparoscopy to Reduce Pain

Todd M. Beste, MD, James A. Daucher, MD, and Donald Holbert, PhD

OBJECTIVE

To study whether using 95% humidified, heated carbon dioxide (CO₂) at laparoscopy reduces pain compared with dry, heated CO₂.

METHODS

Patients were randomly assigned to either heated, 95% humidified CO₂ (study group) or heated, dry CO₂ (control group) during laparoscopy. Pain control was achieved per standard protocols. Pain scales were administered the first 4 hours and 24 and 48 hours postoperatively.

RESULTS

The 89 patients available in the intent-to-treat model revealed a decrease in total morphone equivalents and a decrease in pain scores at 1, 2, and 24 hours in the study group. (directional P values < .05). Subgroup analysis in patients without chronic pelvic pain revealed lower mean pain scores at 1, 2, 24, and 48 hours and decreases in postoperative and total morphine equivalents (directional P values < .05) in the study group.

CONCLUSION

At laparoscopy, heated, 95% humidified CO₂ effectively decreases postoperative pain and narcotics usage compared with heated, dry CO₂.