Risks and benefits of pre-operative dexmedetomidine in oral and maxillofacial surgeries: a systematic review

Opioid requirement and pain intensity after mandibular surgeries with dexmedetomidine administration in two ways: intraoperative infusion versus bolus injection

PURPOSE

The purpose of this study is to compare the opioid requirement and pain intensity after surgeries of mandibular fractures with administration of dexmedetomidine by two approaches of infusion and single bolus.

METHODS

In this double-blind clinical trial, the participants were randomized and matched in terms of age and gender in two groups (infusion and bolus). In both groups, the amount of narcotic used, hemodynamic indices, oxygen saturation, and pain intensity were collected based on the ten-point Visual Analogue Scale (VAS) at 7 time points for 24 h. SPSS version 24 software was used for data analysis. A significance level of less than 5% was considered.

RESULTS

A total of 40 patients were included in the study. There was no significant difference between the two groups in terms of gender, age, ASA class, and duration of surgery (P>0.05). There was no significant difference between the two groups in terms of nausea and vomiting and subsequently receiving anti-nausea medication (P>0.05). The need for opioid consumption after surgery was not different in two groups (P>0.05). Infusion of dexmedetomidine reduced postoperative pain more rapidly than its single bolus dose (P<0.05). However, over time, there was no significant difference between the two groups in terms of changes in oxygen saturation variables (P>0.05). Homodynamic indices including heart rate, systolic blood pressure, and diastolic blood pressure in the bolus group were significantly lower than the infusion group (P<0.05).

CONCLUSION

Administration of dexmedetomidine in the form of infusion can reduce postoperative pain better than bolus injection, with less probability of hypotension and bradycardia.

The Beneficial Effect of Preoperative dexmedetomidine in controlling postoperative pain, nausea, and Vomiting After Orthognathic Surgery: A Triple-blind Randomized Clinical Trial

PURPOSE

Controlling postoperative pain and nausea (PONV) following orthognathic surgery can be challenging. The aim of the study was to assess the efficacy of dexmedetomidine (DEX) in reducing pain and preventing nausea and vomiting in subjects undergoing orthognathic surgery.

METHODS

The authors implemented a triple-blinded, randomized clinical trial. Healthy adults with class III jaw deformity scheduled for bimaxillary orthognathic surgery were included. Subjects were randomized to the DEX or placebo groups. The DEX group received premedication with DEX 1 μg/kg IV over 10 minutes followed by a maintenance dose (0.2 μg/kg/hour). while the placebo group received normal saline. The primary outcome variables were postoperative pain, postoperative nausea, and postoperative vomiting . Pain was assessed using a visual analog scale at 1, 3, 6, 12, 18, and 24 hours, postoperatively). Nausea and vomiting were recorded throughout the postoperative period. Statistical analysis was performed using χ², t test, and repeated measures ANOVA with a P value < .05 considered significant.

RESULTS

A total of 60 consecutive subjects with a mean age of 24.6 ± 3.5 years completed the study. There were 38 females (63.33%) and 22 males (36.66%). The mean visual analog scalewas significantly lower in the DEX group at all time-points (P < .05). There was a significantly greater demand for rescue analgesics in the placebo group compared to the DEX group (P = .01). Fourteen subjects (46.7%) in the placebo group and one subject (3.3%) in the DEX group reported nausea (P < .001). Postoperative vomiting was not observed in any of the subjects.

CONCLUSION

Premedication with DEX can be considered a viable treatment option for reducing postoperative pain and postoperative nausea after bimaxillary orthognathic surgery.

Injection of Lidocaine Alone versus Lidocaine plus Dexmedetomidine in Impacted Third Molar Extraction Surgery, a Double-Blind Randomized Control Trial for Postoperative Pain Evaluation

Objectives

Administration of medications such as dexmedetomidine as a topical anesthetic has been suggested in the pain control in dentistry. This double-blind randomized control trial study evaluated postoperative pain and associated factors following impacted third molar extraction surgery. Lidocaine alone was taken as the control and lidocaine plus dexmedetomidine as the intervention.

Materials and Methods

Forty patients undergoing mandibular third molar extraction entered the study and were randomly allocated to the control and interventional groups. 0.15 ml of dexmedetomidine was added to each lidocaine cartridge and the drug concentration was adjusted to 15 μg for the intervention group while only lidocaine was used in the control group. A visual analog scale was used to measure and record pain levels at the end of the surgery and 6, 12, and 24 hours after the surgery and number of painkillers taken by the patients after the surgery was also recorded.

Results

Pain scores of the intervention group decreased significantly during the surgery and also 6, 12, and 24 hours after the surgery compared to the control group. The pain score was correlated significantly with our intervention during the surgery and also 6 and 12 hours after that (all P value < 0.05). There was a nonsignificant reduction in the number of painkillers taken by the patients at 6, 12, and 24 hours after surgery (all P value > 0.05).

Conclusion

In patients undergoing molar surgery, administration of a combination of dexmedetomidine and lidocaine is beneficial for the pain control. Clinical Relevance. Compared to the injection of lidocaine alone, combination of dexmedetomidine and lidocaine can be used for a better pain control in molar surgeries.

Dexmedetomidine for prevention of postoperative pulmonary complications in patients after oral and maxillofacial surgery with fibular free flap reconstruction:a prospective, double-blind, randomized, placebo-controlled trial

BACKGROUND

Postoperative pulmonary complications (PPCs) are common and significant problems for oral and maxillofacial surgery patients. Dexmedetomidine (DEX), an α₂-adrenoreceptor agonist, has been proven having lung protection effects. However, since now, there has not been final conclusion about whether DEX can reduce the incidence of PPCs. We hypothesize that, in oral and maxillofacial surgery with fibular free flap reconstruction patients, DEX may decrease the incidence of PPCs.

METHODS

This was a prospective, double-blind, randomized, placebo-controlled, single-centered trial with two parallel arms. A total of 160 patients at intermediate-to-high risk of PPCs undergoing oral and maxillofacial surgery with fibular free flap reconstruction and tracheotomy were enrolled and randomized to receive continuous infusion of either DEX or placebo (normal saline). 0.4 μg/kg of DEX was given over 10mins as an initial dose followed by a maintaining dose of 0.4 μg/kg/h till the second day morning after surgery. At the same time, the normal saline was administered a similar quantity. The primary outcome was the incidence of PPCs according to Clavien-Dindo score within 7 days after surgery.

RESULTS

The two groups had similar characteristics at baseline. 18(22.5%) of 80 patients administered DEX, and 32(40.0%) of 80 patient administered placebo experienced PPCs within the first 7 days after surgery (relative risk [RR] 0.563,95% confidence interval [CI] 0.346-0.916; P = 0.017). In the first 7 days after surgery, the DEX group had a lower incidence of PPCs and a better postoperative survival probability (Log-rank test, P = 0.019), and was less prone to occur PPCs (Cox regression, P = 0.025, HR = 0.516). When the total dose of DEX was more than 328 μg, the patients were unlikely to have PPCs (ROC curve, AUC = 0.614, P = 0.009).

CONCLUSIONS

For patients undergoing oral and maxillofacial surgery with fibular free flap reconstruction and tracheotomy who were at intermediate or high risk of developing PPCs, continuous infusion of DEX could decrease the occurrence of PPCs during the first 7 days after surgery and shorten the length of hospital stay after surgery, but did not increase the prevalence of bradycardia or hypotension.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, www.chictr.org.cn, number: ChiCTR1800016153; Registered on May 15, 2018.

Comparative Evaluation of IV Paracetamol Versus IV Dexmedetomidine in Inpatient Oral and Maxillofacial Surgery: A Double-Blinded Randomized Controlled Study

Purpose

Reconstructive surgeries following fractures in the maxillofacial region often involve considerable bone manipulation, and paracetamol is a commonly used analgesic medication in both intraoperative and postoperative periods. Dexmedetomidine, an alpha-2 adrenoceptor agonist, has both sedative and analgesic properties with minimal cardiorespiratory effects and has been used primarily for its sedative properties in oral and maxillofacial surgery.

Aims and Objectives

To compare the intraoperative analgesic requirements among patients undergoing oral and maxillofacial surgery who receive IV paracetamol versus IV dexmedetomidine. The time to requirement for the first postoperative analgesic dose and safety and adverse events of both medications were also assessed.

Patients and Methods

In total, 64 patients needing primary reconstructive surgery for facial fractures were recruited and divided into two groups for this double-blinded study. Patients were randomized to receive a preinduction dose of either IV paracetamol 1 g (Group P) or IV dexmedetomidine 1 µg/kg (Group D). Sedation scores (Ramsay sedation scale), maximal interincisal distance and pain scores at maximal mouth opening (visual analogue scale) were assessed in both groups just prior to and after the administration of the study drugs. After induction, Group P and Group D received a maintenance dose of normal saline and dexmedetomidine (0.5 µg/kg/h) during the intraoperative period, respectively. Standard noninvasive cardiorespiratory monitoring was done for the entire duration of surgery. Following extubation, postoperative pain scores and the time to request for first analgesic dose in either group were recorded.

Results

The time taken to perform the surgery was comparable in both groups. There was a significant difference between the groups in visual analogue scores and interincisal distance after the bolus dose (p < 0.05). Systolic and diastolic blood pressure was significantly lower in Group D at around 150 and 175 min of surgery. While the intraoperative fentanyl consumption was comparable in both groups, the time to request for the first analgesic dose in the postoperative period was significantly delayed in Group P (p < 0.05). No adverse cardiopulmonary events were observed in either group.

Conclusion

The intraoperative anesthetic and analgesic requirements and hemodynamic stability were comparable in IV paracetamol and dexmedetomidine groups. Dexmedetomidine did not confer any enhanced analgesia effect in the postoperative period. More research examining the role of dexmedetomidine for longer duration inpatient oral and maxillofacial surgery is needed.

Clinical Trial Number

http://ClinicalTrials.gov (No. CTRI/2017/08/009468).

Safety and sedative effect of intranasal dexmedetomidine in mandibular third molar surgery: a systematic review and meta-analysis

Objective

The focus of this meta-analysis was to assess the sedative effect and safety of intranasal dexmedetomidine (Dex) in mandibular third molar surgery.

Methods

The PubMed/Medline, Web of Science, Cochrane Library, and China National Knowledge Infrastructure databases were searched for studies published until May 1, 2018. Eligible studies were restricted to randomized controlled trials (RCTs) and controlled clinical trials. The evaluation indicators mainly included the bispectral index, observer assessment of alertness/sedation scale, systolic blood pressure, and heart rate. Data for each period in the Dex and control groups were pooled to evaluate its sedative effect and safety.

Results

Five RCTs met the inclusion criteria. This study included 363 patients: 158 patients received intranasal inhalation of Dex before surgery, and 158 patients were negative controls. The pooled results showed a good sedative effect during tooth extraction when intranasal inhalation of Dex was performed 30 minutes before third molar extraction (assessment of alertness/sedation, Dex vs control SMD −1.20, 95% CI −1.73 to −0.67, I²=0, P=0.95; bispectral index, Dex vs control SMD −11.68, 95% CI −19.49 to −3.87, I²=89%; P=0.0001), and parameters returned to normal within 90 minutes after inhalation. During the operation, blood pressure and heart rate decreased to some extent, but the decreases did not exceed 20% of the baseline, and all patients returned to normal conditions within 90 minutes after inhalation.

Conclusion

Intranasal inhalation of Dex 30 minutes before third molar extraction can provide a good sedative effect, and large-sample multicenter RCTs are needed to evaluate the analgesic effect of Dex.