Dexmedetomidine is effective for conscious sedation during dissection of colorectal lesions and is associated with greater patient satisfaction with the procedure, researchers have found.
The randomized study found that dexmedetomidine (Precedex, Hospira) may be an appealing substitute for propofol, which has a relatively smaller margin of safety, or for deeper sedation with other agents.
“We believe that dexmedetomidine is an ideal sedation method for colorectal endoscopic submucosal dissection [ESD],” said Hideaki Kinugasa, MD, of Hiroshima City Hiroshima Citizens Hospital in Japan, who presented the findings at the 2018 Digestive Disease Week (abstract 921).
“Deep sedation is often desirable for ESD of lesions in the esophagus and stomach. However, the suitable sedation level in colorectal ESD is different,” Dr. Kinugasa said.
Sedation can have variable effects on respiration, he explained, which can be an issue during colorectal ESD, as patients often must hold their breath or change position during the procedure. Dexmedetomidine is notable for its ability to provide sedation without the risk for respiratory depression associated with propofol.
“Conscious sedation for colorectal ESD has not been standardized, and there are no studies of sedation” in that setting, he said.
The study enrolled 80 patients undergoing ESD of colorectal lesions. Patients were assigned to receive placebo or dexmedetomidine (induction dose, 6 mcg/kg per hour; maintenance dose, 0.4 mcg/kg per hour), with pethidine as an analgesic in both groups. Demographics and disease characteristics were similar in both groups.
The primary outcome was patient satisfaction, based on a 10-point visual analog scale (VAS). Among 13 secondary outcomes were patient pain level (VAS), endoscopist satisfaction, patient movement during ESD, resection time and frequency of side effects.
Numerous End Points Favor DEX
Dexmedetomidine outperformed placebo across multiple outcomes, Dr. Kinugasa reported (Table). Patient satisfaction was scored at 9.1, versus 8.4 for placebo (P=0.018). Regarding the secondary outcomes, patient pain level, endoscopist satisfaction, patient pain as judged by the endoscopist, and incidence of side effects all were significantly better for dexmedetomidine than placebo.
| Table. Secondary Outcomes for Dexmedetomidine Versus Placebo for Conscious Sedation | |||
| End Point | Placebo | Dexmedeto- midine |
P Value |
|---|---|---|---|
| Patient perception of pain with ESD, VAS score | 1.2 | 0.4 | 0.045 |
| Endoscopist satisfaction with ESD, VAS score | 8.2 | 9.3 | <0.001 |
| Objective patient pain as judged by endoscopist, VAS score | 1.2 | 0.5 | 0.002 |
| Difficulty of procedure, VAS score | 5.4 | 2.8 | 0.155 |
| Patient’s response, % | 100 | 100 | 1.00 |
| En bloc resection, % | 100 | 100 | 1.00 |
| R0 resection, % | 100 | 97.5 | 0.314 |
| Median resection time, min | 86.5 | 80.0 | 0.736 |
| Median resected tumor size, mm | 30 | 34 | 0.205 |
| Median dose of pethidine, mg | 70 | 70 | 0.963 |
| Side effects: Hypoxia, % Bradycardia, % Hypotension, % |
0 0 0 |
7.5 7.5 5.0 |
0.030 |
| Complications: Perforation, % Post-op bleeding, % |
0 0 |
0 2.5 |
0.367 |
| ESD, endoscopic submucosal dissection; VAS, visual analog scale | |||
“All of these were significantly better results—patients were more comfortable and had less dexmedetomidine pain—in the group,” he said. “No additional medication was needed.”
Significantly more patients receiving dexmedetomidine slept through the procedure (33% vs. 6%; P<0.001). No patient in either group was deeply sedated, and none in either arm was restless, according to the researchers.
Jonathan Cohen, MD, a clinical professor of medicine at NYU Langone Health in New York City, noted that a comparison between dexmedetomidine and deep sedation with propofol would be useful. “Basically, the patients were still conscious, but they were more sedated than usual and they felt better than the controls,” he said. “From our long-standing experience with combinations of opiates and benzodiazepines, we are accustomed to the observation that combinations of medications can produce a little better sedation. The bottom line is [that] a little more sedation helps.”