Abstract
Introduction
We decided to compare dexmedetomidine with propofol regarding several anesthetic and surgical aspects, during stapedotomy done under conscious sedation.
Materials and Method
Thirty patients aged 20–50 years with (American Society of Anesthesiology) ASA class I-II, were assigned to two groups of propofol and dexmedetomidine using a random number table. In dexmedetomidine group, patients received dexmedetomidine infusion (0.5 µg/kg/h) and in the control group, propofol was administered (3 mg/kg/h).Time to reach the desired Ramsey Sedation Score (RSS) and time to reach Aldrete score ≥ 9; incidence of inadvertent movement and amnesia; as well as patients’ and surgeons’ level of satisfaction and degree of bleeding was recorded. Data on hemodynamic variables were monitored and recorded at several intervals.
Results
The mean time taken to reach the RSS (2–4) was 10.3 ± 2.1 min in dexmedetomidine group and 3.1 ± 1.2 min in propofol group. Time to reach Aldrete score ≥ 9 for patients sedated with dexmedetomidine was 8.6 ± 2.1 min and for propofol group was 4.6 ± 1.4 min (p value < 0.05).There were also significant differences between two groups in terms of surgeon’s satisfaction with sedation, and the amount of intra operative bleeding.
Conclusion
According to the results of this study, it can be concluded that dexmedetomidine is a better choice for conscious sedation than propofol. However, the time to reach the required sedation in the dexmedetomidine group was significantly longer.
Keywords: Propofol, Dexmedetomidine, Stapedotomy, Conscious sedation
Introduction
Abnormal growth of spongy bone in the otic capsule causes otosclerosis. In addition to progressive hearing loss, some patients with otosclerosis may experience dizziness and tinnitus. Otosclerosis can be treated by performing stapedectomy or stapedotomy. In stapedectomy footplate of stapes is removed and replaced by a small prosthesis, while in stapedotomy a small hole in the fixed stapes footplate is created and a piston-like prosthesis positioned in place. Both procedures can be done under local anesthesia and sedation [1]. Cooperation between patient and surgeon and hearing test during this procedure is vital not only during, but also in the outcome of surgery. Other important points to be considered during these surgeries include reduction of bleeding, surgeon’s appropriate field under the microscope, maintenance of airway and spontaneous breathing, adequate analgesia, rapid recovery, and prevention and reduction of postoperative nausea and vomiting. Dexmedetomidine is a selective α-2 adrenergic agonist with the capability of producing conscious sedation without causing respiratory depression. The peripheral and central effects of this drug involve a decrease in arterial blood pressure, heart rate, and cardiac output [2]. Propofol is a very short acting sedative–hypnotic agent with a rapid recovery, is associated with a significant decrease in postoperative nausea and vomiting, and results in a decreased level of consciousness, lack of memory for events, and the development of euphoria [3]. Accordingly, the level of patient’s satisfaction increases by administrating propofol. Propofol has no analgesic effect and can produce dose-dependent respiratory depression [3]. In patients undergoing stapedotomy surgery, relative awareness and the patient’s collaboration are of particular importance and should be considered during the administration of sedative drugs in these patients. Moreover, special attention is also given to maintenance of airway and spontaneous breathing. We currently sedate patients using propofol infusion. During surgery, we sometimes may run into a number of problems such as the patient's lack of cooperation, excessive sleepiness, patient’s shivering/abnormal motion, respiratory depression, and insufficient analgesia; each of which requires special measure. Regarding dexmedetomidine capability of producing sedative, analgesic, anesthetic and sympathetic effects without causing respiratory depression, we decided to examine this drug and compare it with propofol. In addition, the hemodynamic stability and bleeding reduction associated with the use of dexmedetomidine can be desirable.
Materials and Methods
After approval by local ethics committee (IR.SSU.MEDICINE.REC.1395.84, 2016.07.16) and obtaining informed written consent, this randomized double-blinded clinical trial study was done on thirty patients aged 20–50 years with ASA class I-II who were scheduled for stapedotomy. Patients with history of cardiovascular diseases, pulmonary hypertension, sever obesity, liver and kidney diseases, coagulopathy, history of narcotic use and depression were excluded. Patients were assigned in two groups of propofol or dexmedetomidine using a random number table. Patients received ringer solution (5 cc/kg) in the operating room. All patients were monitored continuously by noninvasive blood pressure, pulse-oximetry, and electrocardiography. For all patients, supplemental oxygen was delivered through nasal cannula. As premedication, fentanyl 2 μg/kg and midazolam 0.15 mg/kg were administered. All of the patients received Granisetron 1 mg IV before the surgery to prevention of post operation nausea and vomiting. In dexmedetomidine group, patients received dexmedetomidine infusion (0.5 µg/kg/h); and in the propofol group, patients received propofol infusion (3 mg/kg/h). Surgery was initiated when Ramsay sedation score of 2–4 and local anesthesia of great auricular and tympanic branch of auriculo temporal nerves using lidocaine 2% and epinephrine 1:200.000 were achieved. The time taken to reach this degree of sedation was recorded. Extra doses of propofol in case of RSS decrease below 2 for both groups were administered. During the surgery, every 5–10 min, the degree of sedation based on RSS was recorded. The systolic, diastolic, mean arterial blood pressure, and heart rate were measured before the surgery, before anesthetic infusion, 5, 10, 30, and 60 min after the infusion of the drug, at the end of the surgery, 0, 10, and 5 min after the discontinuation of drug infusion, and at the time of admitting and discharging from the recovery room. In addition to hearing status, vertigo and nistagmous was evaluated in all of our patients during the surgery.. After the operation, the infusion of the medicine was discontinued and the patient was transferred to the recovery room after 10 min. The patient was monitored in the recovery room and discharged from the recovery room when Aldrete sedation scale ≥ 9 was achieved. Sedation duration (from reaching RSS 2–4 to end of anesthetic infusion), surgery duration (from local anesthetic injection until the end of the surgery), and recovery duration (from admitting to recovery room until Aldrete sedation scale ≥ 9 was achieved) were recorded. Based on visual analogue scale (VAS, 0–10), the surgeon and the patient’s level of satisfaction regarding sedation was recorded. Amnesia during surgery was also asked from the patients in the ward. With respect to surgeon's opinion, the degree of bleeding was also recorded in two groups using a 5 degree (0–4) scale. All measurements related to blood pressure and heart rate were performed digitally. Data were recorded by a person who was not aware of the prescribed drug (assistant). For comparing the data obtained from study groups student t test or Fisher’s exact test was used as appropriate. Data were analyzed by R software []. p < 0.05 was considered as a significant level. Dexmedetomidine used in this study was from HospiraTM Company (USA), and it was in the form of a vial of 200 µg per 2 cc and propofol 10 mg/ml (1%) was obtained from Chacharwadi-Vasana Company (India).
Results
The demographic data of the groups are presented in (Table 1). Both groups were comparable with respect to demographic characteristics. Incidence of inadvertent movement and frequency of intra operative amnesia were not statistically different between groups (Table 2). Two cases from dexmedetomidine group and 3 cases from propofol group needed extra dose of propofol to keep RSS above 2, which was not statistically significant as well. No patients developed over sedation (RSS > 4).Total sedation time, total surgery time and patient’s satisfaction with sedation (based on VAS criteria), were not statistically significant between the studied groups (Table 3). The mean of surgeon’s satisfaction with sedation was 7.9 ± 1.5 in dexmedetomidine group and 6.6 ± 1.3 in propofol group (p < 0.018). A significantly less bleeding was encountered in dexmedetomidine group compared to propofol group (p < 0.037) (Table 3 & Fig. 1). The mean time to reach the RSS (2–4) was 10.3 ± 2.1 min in dexmedetomidine group and 3.1 ± 1.2 min in propofol group.Time to reach Aldrete score ≥ 9 for patients sedated with dexmedetomidine was 8.6 ± 2.1 min and for propofol group was 4.6 ± 1.4 min. Both of these time intervals were significantly longer in dexmedetomidine sedated patients (p < 0.001) (Table 3). The results showed that the mean of RSS at 5and 10 min following the initiation of anesthetic infusion were lower in dexmedetomidine group (Table 4). This finding is a reflection of longer duration of sedation induction of dexmedetomidine. Systolic, diastolic and arterial blood pressures as well as heart rate, before surgery and most of the time points at which blood pressure and heart rate had been measured did not differ significantly between groups. However, at some time point during sedation these measure were lower in dexmedetomidine group (Table 5 and Figs. 2, 3, 4, 5).
Table 1.
Patients’ demographics
| Variable | SD ± Mean | P-value | ||
|---|---|---|---|---|
| Dexmedetomidine | Propofol | Total | ||
| Age (years) | 6.7 ± 31.87 | 6.6 ± 31.27 | 6.65 ± 31.57 | 0.808 |
| Weight (Kg) | 10.6 ± 67.80 | 15.63 ± 70.67 | 13.32 ± 69.23 | 0.566 |
| Sex (male) | 7 | 8 | 15 | 0.715 |
| Sex (female) | 8 | 7 | 15 | 0.715 |
Table 2.
Incidence of inadvertentmovement and frequency of intraoperative amnesia
| Variable | Frequency of patients with inadvertent movement and amnesia | P-value | |
|---|---|---|---|
| Dexmedetomidine | Propofol | ||
| Inadvertent movement | 5 | 4 | 0.5 |
| Amnesia | 6 | 10 | 0.17 |
Table 3.
Mean values ± standard deviation of duration of sedation and surgery; surgeon’s and patient’s satisfaction with sedation; time to reach the RSS(2–4) and Aldrete > 9; and the amount of intraoperative bleeding
| Variable | Mean ± SD | P-value | |
|---|---|---|---|
| Dexmedetomidine | Propofol | ||
| Duration of sedation (Minutes) | 7 ± 73.5 | 10 ± 67.4 | 0.07 |
| Duration of surgery (Minutes) | 7 ± 63.1 | 10 ± 64.4 | 0.69 |
| Patient’s satisfaction (VAS. 1–10) | 7.1 ± 1.6 | 5.8 ± 1.5 | 0.039 |
| Surgeon’s satisfaction (VAS. 1–10) | 7.9 ± 1.5 | 6.6 ± 1.3 | 0.018 |
| Intraoperative bleeding (0–4) | 0.85 ± 0.93 | 1.1 ± 1.73 | 0.037 |
| Time to RSS 2–4 (Minutes) | 10.3 ± 2.1 | 3.1 ± 1.2 | 0.001 |
| Time to Aldrete > 9 (Minutes) | 8.6 ± 2.1 | 4.6 ± 1.4 | 0.001 |
Fig. 1.
RSS mean values ± standard deviation at specified time points
Table 4.
RSS mean values ± standard deviation at specified time points
| SD ± RSS mean values | P-value | ||
|---|---|---|---|
| Dexmedetomidine | Propofol | ||
| 5 min after infusion | 0.25 ± 1.07 | 0.8 ± 2.8 | 0.001 |
| 10 min after infusion | 0.83 ± 1.8 | 0.65 ± 3.2 | 0.001 |
| 15 min after infusion | 0.57 ± 3.27 | 0.5 ± 3.53 | 0.19 |
| 20 min after infusion | 0.64 ± 3.47 | 0.5 ± 3.47 | 1 |
| 25 min after infusion | 0.64 ± 3.53 | 0.48 ± 3.31 | 0.34 |
| 30 min after infusion | 0.59 ± 3.07 | 0.5 ± 3.38 | 0.11 |
| 40 min after infusion | 0.48 ± 3.33 | 0.5 ± 3.54 | 0.29 |
| 50 min after infusion | 0.61 ± 3.33 | 0.43 ± 3.77 | 0.11 |
| 60 min after infusion | 0.63 ± 3.40 | 0.4 ± 3.77 | 0.09 |
Table 5.
Mean values of systolic, diastolic, mean arterial blood pressure and heart rate of patients at specified time points
| In OR before infusion | 5` after infusion | 10` after infusion | 30` after infusion | 60` after infusion | after ending infusion | 5` after ending infusion | 10` after ending infusion | Entrance to recovery room | Discharge from recovery room | ||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Mean Systolic BP | Dexmedetomidine | 114 | 106 | 97 | 94 | 91 | 93 | 99 | 105 | 109 | 110 |
| Propofol | 113 | 109 | 104 | 104 | 103 | 102 | 105 | 113 | 113 | 113 | |
| P Value | 0.93 | 0.55 | 0.09 | 0.02 | 0.00 | 0.05 | 0.11 | 0.11 | 0.45 | 0.64 | |
| Mean Diastolic BP | Dexmedetomidine | 75 | 69 | 66 | 59 | 57 | 56 | 61 | 65 | 68 | 72 |
| Propofol | 74 | 72 | 66 | 64 | 65 | 64 | 67 | 71 | 72 | 73 | |
| P Value | 0.66 | 0.42 | 0.98 | 0.12 | 0.01 | 0.02 | 0.09 | 0.12 | 0.39 | 0.71 | |
| Mean Arterial BP | Dexmedetomidine | 88 | 81 | 76 | 71 | 68 | 68 | 73 | 78 | 82 | 84 |
| Propofol | 87 | 84 | 79 | 77 | 78 | 77 | 80 | 85 | 85 | 86 | |
| P Value | 0.71 | 0.41 | 0.46 | 0.03 | 0.00 | 0.01 | 0.06 | 0.08 | 0.36 | 0.65 | |
| Mean Heart Rate | Dexmedetomidine | 77 | 73 | 68 | 65 | 60 | 61 | 69 | 72 | 74 | 74 |
| Propofol | 75 | 75 | 72 | 71 | 68 | 68 | 69 | 71 | 73 | 75 | |
| P Value | 0.70 | 0.74 | 0.27 | 0.05 | 0.04 | 0.08 | 0.95 | 0.79 | 0.65 | 0.79 | |
Fig. 2.
Mean values of systolic blood pressure of patients at specified time points
Fig. 3.
Mean values of diastolic blood pressure of patients at specified time points
Fig. 4.
Mean values of arterial blood pressure of patients at specified time points
Fig. 5.
Mean values of heart rate of patients at specified time points
Discussion
The aim of this study was to compare propofol and dexmedetomidine in terms of induction of conscious sedation during stapedotomy surgery. Several important measures regarding surgeon’s satisfaction and patient’s convenience and cooperation during surgery were monitored. Moreover, the swiftness of induction of sedation and recovery from it, in addition to perioperative hemodynamic changes were measured. In our study the elapsed time to reach RSS of 2-4was significantly longer in dexmedetomidine sedated patients. This longer duration results from the pharmacologic properties of dexmedetomidine and propofol. More rapid action of propofol than dexmedetomidine in induction of conscious sedation was observed by several researchers [4, 5]. Significantly higher RSS was observed at 5 and 10 min following infusion of propofol, but thereafter there were no difference between studied groups in this regard. Leena Goel et al. evaluated the effect of dexmedetomidine and propfol for conscious sedation in middle ear surgery under monitored anaesthesia care and their results proposed that compare to propofol, dexmedetomidine provided more sufficient sedation with analgesia with good surgeon and patient ease without any adverse effect for patients being operated for middle ear surgery under local anesthesia that their results is in line with our results [6]. Nallam et al. compared nalbuphine /dexmedetomidine versus nalbuphine /propofol in middle ear surgeries [7]. They have recorded higher RSS in dexmedetomidine group than propofol group, which did not correlate with the results of our study indicating that the RSS at 15, 20, 25, 30, 40, 50 and 60 min in both groups were comparable. This inconsistency can be attributed to the difference in the methodology of two studies; they used lower dose of propofol (1.5 mg/kg/hr) and compared dexmedetomidine and propofol in combination with nalbuphine, not individually. Other studies that compare RSS between patients who received dexmedetomidine or propofol in different anesthetic settings did not show statistically significant difference [4, 8]. Bloodless microscopic operative field and absence of patient’s inadvertent movement during surgery, contribute to surgeon’s satisfaction. We compared these variables individually between groups. In our study surgeons were more satisfied with operations on patients sedated with dexmedetomidine. Oligemic surgical field by infusion of dexmedetomidine during middle ear surgery under general anesthesia was reported by Gupta et al. [9]. Acceptable bleeding score was achieved by a higher number of patients in dexmedetomidine as compared to propofol in Nallem study [7]. Surgeons of these studies were more satisfied with dexmedetomidine sedated patients as compared to propofol. Less intra operative bleeding in dexmedetomidine as compared to propofol may result from lower heart rate and blood pressures, which was observed at some time points in our study and others. In several studies patients reported less disturbing experience from surgery or endoscopy when they were sedated with dexmedetomidine [7, 8, 10]. Also, in our study the VAS score of patient’s satisfaction in dexmedetomidine group were higher than that of propofol. Wang et al. also did not find dexmedetomidine a better choice that propofol to achieve patients satisfaction in inguinal hernia repair [11]. In contrast Wu et al. find propofol more suitable than dexmedetomidine regarding patient’s satisfaction in esophago-gastro-duodenoscopy [5].The length of sedation and time taken for discharging from recovery were longer in dexmedetomidine group according to several studies [4, 5, 7, 12].Their findings are consistent with the results of our study and results in part from longer time to reach Aldrete sedation score ≥ 9, in the dexmedetomidine group than the propofol group. In a study comparing dexmedetomidine and propofol mean arterial pressure in the propofol group decreased during esophago-gastro-duodenoscopy in comparison with the dexmedetomidine group, while heart rate (HR) decreased more in the dexmedetomidine group [5]. In a clinical trial comparing the dexmedetomidine with propofol, in combination with fentanyl for conscious sedation in inguinal hernia surgery heart rate was significantly lower in dexmedetomidine than propofol from 30 to 60 min of surgery [11]. Significant decrease in systolic and diastolic blood pressure as well as HR was observed 30 min after sedation with dexmedetomidine as compared to propofol in uvulo-palato-pharyngoplasty [8]. HR and mean arterial blood pressure were lower in dexmedetomidine than in propofol after 10 min from the start to the end of the procedure as reported in Nallam study [7]. The results of these investigations correlate with our study, in terms of dexmedetomidine ability to decrease heart rate and blood pressure at some time points during conscious sedation. Since stapedotomy is mostly performed during the 3rd and 4th decade of life and our patients were in ASA class I-II, dexmedetomidine is a safe choice in this patient population. However, close monitoring of hemodynamic measures should be considered. In this study we focused on variables with influence on surgeon’s and patient’s satisfaction, as well as some important hemodynamic variables potentially affecting the surgical field. Numerous variables (e.g. SpO2, ETCO2) could be measured and reported, but due to their less effect over surgeon’s and patient’s satisfaction these were just monitored and not reported.
Conclusion
Comparing two groups of dexmedetomidine and propofol, longer sedation time, significantly higher surgeons' and patients' satisfaction, less intra operative bleeding and hence better microscopic surgical field, was observed in the dexmedetomidine group. Significantly shorter time taken to reach required sedation in propofol group was observed. In conclusion, it can be concluded that dexmedetomidine has better sedative efficacy and less complications than propofol; therefore, it is recommended to administer dexmedetomidine instead of propofol in patients undergoing stapedotomy surgery.
Declarations
Conflict of interest
Authors have no conflicts of interest.
Ethical approval
Study protocol was in accordance with the latest Declaration of Helsinki for medical research involving human subjects and was approved by ethics committee of Shahid Sadoughi University of medical sciences.
Human and animal rights
This article does not contain any studies with animals performed by any of the authors.
Informed consent
Informed consent was obtained from all participants of the study.
Footnotes
Publisher's Note
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References
- 1.Flint PW, Haughey BH, Robbins KT, Thomas JR, Niparko JK, Lund VJ, et al (2014) Cummings otolaryngology- head and neck surgery E-book. Elsevier Health Sciences
- 2.Belleville JP, Ward DS, Bloor BC, Maze M. Effects of intravenous dexmedetomidine in humans. I. Sedation, ventilation, and metabolic rate. Anesthesiology. 1992;77(6):1125–33. doi: 10.1097/00000542-199212000-00013. [DOI] [PubMed] [Google Scholar]
- 3.Miller RD. Miller's anesthesia. 8. Philadelphia: Elsevier Saunders; 2015. [Google Scholar]
- 4.Yektas A, Gumus F, Alagol A. Dexmedetomidine and propofol infusion on sedation characteristics in patients undergoing sciatic nerve block in combination with femoral nerve block via anterior approach. Braz J Anesthesiol. 2015;65(5):371–378. doi: 10.1016/j.bjane.2014.01.003. [DOI] [PubMed] [Google Scholar]
- 5.Wu Y, Zhang Y, Hu X, Qian C, Zhou Y, Xie J. A comparison of propofol vs. dexmedetomidine for sedation, haemodynamic control and satisfaction, during esophagogastroduodenoscopy under conscious sedation. J Clin Pharm Ther. 2015;40(4):419–25. doi: 10.1111/jcpt.12282. [DOI] [PubMed] [Google Scholar]
- 6.Goel L, Goel M. A prospective randomized comparative study of dexmedetomidine and propfol for conscious sedation in middle ear surgery under monitored anaesthesia care. Indian Journal of Clinical Anaesthesia. 2016;3(2):179–183. doi: 10.5958/2394-4994.2016.00055.X. [DOI] [Google Scholar]
- 7.Nallam SR, Chiruvella S, Reddy A. Monitored anaesthesia care–Comparison of nalbuphine/dexmedetomidine versus nalbuphine/propofol for middle ear surgeries: A double-blind randomised trial. Indian J Anaesth. 2017;61(1):61–67. doi: 10.4103/0019-5049.198403. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 8.Xu J, Jin C, Cui X, Jin Z. Comparison of Dexmedetomidine versus Propofol for Sedation after Uvulopalatopharyngoplasty. Med Sci Monit. 2015;21:2125–2133. doi: 10.12659/MSM.893884. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 9.Gupta K, Bansal M, Gupta PK, Pandey M, Agarwal S. Dexmedetomidine infusion during middle ear surgery under general anaesthesia to provide oligaemic surgical field: A prospective study. Indian J Anaesth. 2015;59(1):26–30. doi: 10.4103/0019-5049.149445. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 10.Shah PJ, Dubey KP, Sahare KK, Agrawal A. Intravenous dexmedetomidine versus propofol for intraoperative moderate sedation during spinal anesthesia: A comparative study. J Anaesthesiol Clin Pharmacol. 2016;32(2):245–249. doi: 10.4103/0970-9185.168172. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 11.Wang HM, Shi XY, Qin XR, Zhou JL, Xia YF. Comparison of dexmedetomidine and propofol for conscious sedation in inguinal hernia repair: A prospective, randomized, controlled trial. J Int Med Res. 2017;45(2):533–539. doi: 10.1177/0300060516688408. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 12.Yuan F, Fu H, Yang P, Sun K, Wu S, Lv M, et al. Dexmedetomidine-fentanyl versus propofol-fentanyl in flexible bronchoscopy: A randomized study. Exp Ther Med. 2016;12(1):506–512. doi: 10.3892/etm.2016.3274. [DOI] [PMC free article] [PubMed] [Google Scholar]