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

Is the Use of Dexmedetomidine Upon Emergence From Anesthesia Associated With Neck Hematoma Formation Following Head and Neck Microvascular Reconstruction?

BACKGROUND

Dexmedetomidine (DEX) is a highly selective alpha-2-receptor agonist, and its use has not been well studied in major microvascular reconstructive surgery of the head and neck.

PURPOSE

The purpose is to measure the association between DEX and neck hematoma formation in subjects undergoing head and neck microvascular reconstructive surgery.

STUDY DESIGN, SETTING, SAMPLE

The investigators implemented a retrospective cohort study on subjects undergoing microvascular head and neck reconstruction for benign and malignant pathology at the University of Alabama at Birmingham from 2014 to 2021. Patients with unresectable tumors were excluded.

PREDICTOR VARIABLE

The predictor variable was the intraoperative use of DEX upon emergence from general anesthesia. Subjects received standard anesthetic drugs and DEX, while control subjects received only standard anesthetic drugs.

MAIN OUTCOME VARIABLE(S)

The primary outcome was postoperative neck hematoma formation necessitating a return to the operating theater. The secondary outcome was the length of stay (LOS).

COVARIATES

The covariates were demographic, operative, and oral morphine equivalents of anesthesia drugs.

ANALYSES

Bivariate analyses were performed using the Student's t-test and the χ2 test for continuous and categorical variables. Multivariate regression analyses were conducted to assess for associations between DEX and the outcomes adjusted for confounding variables when present. P values of < .05 were regarded as statistically significant.

RESULTS

A total of 297 subjects (mean age, 59.6 years, and standard deviation [SD], 14.9) with 61.6% male received DEX, and 304 subjects (mean age, 58.9 years, and SD, 14.6) with 60.2% male served as controls (P > .5). A total of 11 postoperative neck hematoma occurred in the control group when compared to 2 in the DEX (relative risk = 5.4, 95% confidence interval [CI], 1.2 to 24, P = .02). The mean LOS was 7.7 (SD, 4.3) and 9.4 (SD, 8.1) for the DEX and control groups (95% CI, 0.7 to 2.8, P < .01). After adjusting for tobacco history, tracheostomy, and neck dissection, DEX (Beta coefficient (B) = -1.7, 95% CI -2.7 to -0.7, P < .01) and neck dissection (B = 2.2, 95% CI 1.0 to 3.4, P < .01) were statistically associated with LOS.

CONCLUSION AND RELEVANCE

The use of intraoperative DEX upon emergence from general anesthesia was associated with lower postoperative neck hematoma formation and a shorter length of stay following microvascular head and neck reconstruction.

Effects of penehyclidine hydrochloride combined with dexmedetomidine on pulmonary function in patients undergoing heart valve surgery: a double-blind, randomized trial

AIM

To investigate the effects of penehyclidine hydrochloride combined with dexmedetomidine on pulmonary function in patients undergoing heart valve surgery with cardiopulmonary bypass (CPB).

METHODS

A total of 180 patients undergoing elective heart valve surgery with CPB were randomly divided into four groups: 45 in group P (intravenous penehyclidine hydrochloride 0.02 mg/kg 10 min before anesthesia induction and at the beginning of CPB, total 0.04 mg/kg); 43 in group D (dexmedetomidine 0.5 μg/kg/h after induction of anesthesia until the end of anesthesia); 44 in group PD ( penehyclidine hydrochloride 0.04 mg/kg combined with dexmedetomidine 0.5 μg/kg/h intravenously during anesthesia); and 43 in group C (same amount of normal saline 10 min before and after anesthesia induction, to the end of anesthesia, and at the beginning of CPB). The main outcomes were the incidence and severity of postoperative pulmonary complications (PPCs). The secondary outcomes were: (1) extubation time, length of stay in intensive care, and postoperative hospital stay, and adverse events; and (2) pulmonary function evaluation indices (oxygenation index and respiratory index) and plasma inflammatory factor concentrations (tumor necrosis factor-α, interleukin-6, C-reactive protein and procalcitonin) during the perioperative period.

RESULTS

The incidence of PPCs in groups P, D and PD after CPB was lower than that in group C (P < 0.05), and the incidence in group PD was significantly lower than that in groups P and D (P < 0.05). The scores for PPCs in groups P, D and PD were lower than those in group C (P < 0.05).

CONCLUSION

Combined use of penehyclidine hydrochloride and dexmedetomidine during anesthesia reduced the occurrence of postoperative pulmonary dysfunction, and improved the prognosis of patients undergoing heart valve surgery with CPB.

TRIAL REGISTRATION

The trial was registered in the Chinese Clinical Trial Registry on 3/11/2020 (Registration No.: ChiCTR2000039610).

A Comparative Study on Sedation Efficacy Between General and Regional Anesthesia with Dexmedetomidine in Patients Under Maxillofacial Surgery

BACKGROUND AND OBJECTIVE

Securing the airway in the surgery of maxillofacial disorders and traumas is fundamental during the operation. The present study aims to investigate the beneficial sedative effects of dexmedetomidine (DEX) in patients who underwent maxillofacial surgery with regional anesthesia compared to general anesthesia.

METHODS

Fifty patients, aged 20-45 years old were randomly divided into two groups of regional anesthesia (RA) and general anesthesia (GA) (each n=25). The group RA received regional block with sedation (DEX: 1 μg/kg infused over 10 min followed by the maintenance dose of 0.5 μg/kg/h) and the group GA underwent general anesthesia (DEX: 0.1 μg/kg/min over 10 min followed by 0.4-0.7 μg/kg/h). Postoperative pain scores, anesthesia outcomes, hemodynamic parameters, the time of the post-anesthesia care unit (PACU) discharge and intra and postoperative complications were comparatively assessed in both groups.

RESULTS

The baseline characteristics of the patients (age, gender, BMI, and ASA physical status) showed no differences between the two groups (P>0.05). Although the duration of surgery and recovery time showed no differences between the groups, the duration of anesthesia and extubation time was remarkably lower in the RA group than in the GA group (P<0.01). Administration of nerve blocks demonstrated less pain and longer sleep time in the postoperative phase as compared to the GA group. Heart rate and mean arterial blood pressure were significantly less in the RA group at the end of the loading dose of DEX and incision time (P<0.05). SpO2, respiration rate and Ramsay sedation scale did not exhibit any significant differences between the two groups at all-time points (P>0.05). No significant differences were observed with regard to the adverse events between the two groups (P>0.05).

CONCLUSIONS

Although our findings revealed that both methods are suitable and safe methods for maxillofacial surgery, the outcomes of anesthesia with regional block and sedation include less pain in the postoperative phase, shorter extubation time and earlier discharge from the PACU demonstrated that this method is more reliable for maxillofacial surgery. Further controlled studies are needed to compare the effectiveness and safety profiles of two RA and GA techniques and also to compare DEX with other anesthetic agents to achieve optimum outcomes in maxillofacial surgeries.

Pulmonary effects of dexmedetomidine infusion in thoracic aortic surgery under hypothermic circulatory arrest: a randomized placebo-controlled trial

Dexmedetomidine has emerged as a promising organ protective agent. We performed prospective randomized placebo-controlled trial investigating effects of perioperative dexmedetomidine infusion on pulmonary function following thoracic aortic surgery with cardiopulmonary bypass and moderate hypothermic circulatory arrest. Fifty-two patients were randomized to two groups: the dexmedetomidine group received 1 µg/kg of dexmedetomidine over 20 min after induction of anesthesia, followed by 0.5 µg/kg/h infusion until 12 h after aortic cross clamp (ACC)-off, while the control group received the same volume of normal saline. The primary endpoints were oxygenation indices including arterial O2 partial pressure (PaO2) to alveolar O2 partial pressure ratio (a/A ratio), (A-a) O2 gradient, PaO2/FiO2 and lung mechanics including peak inspiratory and plateau pressures and compliances, which were assessed after anesthesia induction, 1 h, 6 h, 12 h, and 24 h after ACC-off. The secondary endpoints were serum biomarkers including interleukin-6, tumor necrosis factor-α, superoxide dismutase, and malondialdehyde (MDA). As a result, dexmedetomidine did not confer protective effects on the lungs, but inhibited elevation of serum MDA level, indicative of anti-oxidative stress property, and improved urine output and lower requirements of vasopressors.

Activation of PI3K/Akt/HIF-1α Signaling is Involved in Lung Protection of Dexmedetomidine in Patients Undergoing Video-Assisted Thoracoscopic Surgery: A Pilot Study

Background

Lung resection and one lung ventilation (OLV) during video-assisted thoracoscopic surgery (VATS) may lead to acute lung injury. Dexmedetomidine (DEX), a highly selective α₂ adrenergic receptor agonist, improves arterial oxygenation in adult patients undergoing thoracic surgery. The aim of this pilot study was to explore possible mechanism related to lung protection of DEX in patients undergoing VATS.

Patients and Methods

Seventy-four patients scheduled for VATS were enrolled in this study. Three timepoints (before anesthesia induction (T₀), 40 min after OLV (T₁), and 10 min after two-lung ventilation (T₂)) of arterial blood gas were obtained. Meanwhile, lung histopathologic examination, immunohistochemistry analysis (occludin and ZO-1), levels of tumor necrosis factor (TNF)-α and interleukin (IL)-6 in lung tissue and plasma, and activation of phosphoinositide-3-kinase (PI3K)/AKT/hypoxia-inducible factor (HIF)-1α signaling were detected. Postoperative outcomes including duration of withdrawing the pleural drainage tube, length of hospital stay, hospitalization expenses, and postoperative pulmonary complications (PPCs) were also recorded.

Results

Sixty-seven patients were randomly divided into DEX group (group D, n=33) and control group (group N, n=34). DEX improved oxygenation at T₁ and T₂ (group D vs group N; T₁: 191.8 ± 49.8 mmHg vs 159.6 ± 48.1 mmHg, P = 0.009; T₂: 406.0 mmHg [392.2–423.7] vs 374.5 mmHg [340.2–378.2], P = 0.001). DEX alleviated the alveolar capillary epithelial structure damage, increased protein expression of ZO-1 and occludin, inhibited elevation of the expression of TNF-α and IL-6 in lung tissue and plasma, and increased protein expression of p-PI3K, p-AKT and HIF-1α. Dex administered had better postoperative outcomes with less risk of PPCs and hospitalization expenses as well as shorter duration of withdrawing the pleural drainage tube and length of hospital stay.

Conclusion

Activation of PI3K/Akt/HIF-1α signaling might be involved in lung protection of DEX in patients undergoing VATS.