The Effect of Dexmedetomidine and Esmolol on Early Postoperative Cognitive Dysfunction After Middle Ear Surgery Under Hypotensive Technique: A Comparative, Randomized, Double-blind Study

Magnetic Resonance Imaging Characteristic Evaluation of Dexmedetomidine on Neurocognitive Dysfunction in Elderly Patients with Colorectal Tumors after Laparoscopic Operation

In order to investigate the effects of Dexmedetomidine (DEX) on postoperative anesthesia recovery time and consciousness function in elderly patients with laparoscopic colorectal tumors, 40 patients (20 in the control group and 20 in the DEX group) were selected. The DEX group was intravenously pumped at a rate of 0.8 μg/kg/h for 10 min and then continuously pumped at a rate of 0.3 μg/kg/h until 40 min before the end of the operation. The two groups were given the same amount of normal saline, with the same way of anesthesia. The results showed that the visual analog scale (VAS) score of pain in the two groups decreased signally. Compared with the control group, the inflammatory factors tumor necrosis factor (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6), and macrophage inflammatory protein (MIP-2) in the DEX group were remarkably decreased at T1 and T2 stages, with a considerable difference (P < 0.05). One month after the auxiliary diagnosis of colorectal tumor, no clear nodular, irregular shape patches, or patchy diffuse limited points were found, which indicated that the whole tumor had been removed. In summary, DEX could improve postoperative cognitive function in elderly patients who underwent the laparoscopic radical resection of colon cancer, and its mechanism was related to the reduction of inflammatory factors. Therefore, the anesthesia intervention with DEX during the operation had a positive significance for tumor resection.

Opioid-Free Anesthesia and Postoperative Cognitive Dysfunction After Minor Urological Surgery: A Case Series Study

Background

Postoperative cognitive dysfunction (POCD) is a complication that mainly occurs in adult patients and refers to a new-onset decline in cognitive function after anesthesia and surgery. The literature lacks evidence regarding opioid-free anesthesia and its impact on mental function postoperatively.

Objectives

The effect of opioid-free anesthesia on POCD following urological surgery has not been previously reported. Accordingly, we present a case series of 15 adult patients undergoing transurethral urological surgery under general anesthesia using an opioid-free protocol with dexmedetomidine, ketamine, and lidocaine.

Methods

Patients that underwent simple transurethral elective urological procedures under general opioid-free anesthesia were included. This case series is part of a prospective clinical study regarding opioid-free anesthesia and served as a pilot sample. The mini-mental state examination (MMSE) test, performed preoperatively and 12 hours postoperatively, was applied to assess POCD.

Results

Fifteen patients with a mean age of 68 years old were included in the study. The opioid-free protocol was associated with non-statistically significant changes of the MMSE test after minor urological procedures.

Conclusions

In our study, an opioid-free protocol of general anesthesia, using a mixture of dexmedetomidine, ketamine, and lidocaine, did not seem to have a negative impact on postoperative cognitive function in patients undergoing transurethral urological surgery. Further studies specifically designed to identify this effect are certainly required to further prove such an effect.

A Comparative Study on the Effects of Ketofol, Dexmedetomidine, and Isofol in Anesthesia of Candidates for Dilatation and Curettage

Background

Dilatation and curettage (D & C) is one of the relatively common surgeries among women. Familiarity with the analgesics, along with their different uses and specific characteristics, can help to determine the best and most appropriate drug to control pain in the patients.

Objectives

This study aimed to compare the effects of ketofol, dexmedetomidine, and isofol in anesthesia of candidates for D & C.

Methods

In this double-blind clinical trial, 150 candidates for D & C surgeries with ASA class 1 and 2 were included. Patients were randomly divided into three groups. The first group received ketamine + propofol, the second group received dexmedetomidine, and the third group received isofol (isoflurane + propofol). Any hemodynamic changes or respiratory disorders, including apnea or hypoventilation, drop in the level of blood oxygen saturation, and the need for respiratory support, were recorded and compared.

Results

Hypoventilation was observed in 47 patients in isofol group, 18 in the dexmedetomidine group, and 42 in ketofol group. Also, 48 patients in the isofol group, eight in the dexmedetomidine group, and 33 in the ketofol group experienced apnea. Moreover, 17 patients in the dexmedetomidine group, 35 in the ketofol group, and eight in the isofol group experienced bradycardia. The rate of bradycardia was significantly higher in the dexmedetomidine group (70%) compared to the other two groups, and the rate of hypotension was significantly higher in the isofol group (P = 0.001).

Conclusions

According to the results, dexmedetomidine was associated with fewer complications during general anesthesia in D & C surgery.

Comparison of the Effect of Propofol and Dexmedetomidine on Hemodynamic Parameters and Stress Response Hormones During Laparoscopic Cholecystectomy Surgery

Background

General anesthesia induces endocrine, immunologic, and metabolic responses. Anesthetic drugs affect the endocrine system by changing the level of stress hormones and hemodynamic variables of the patient.

Objectives

The purpose of this study was to compare the effects of propofol and dexmedetomidine on hemodynamic parameters and stress-induced hormones in laparoscopic cholecystectomy (LC) surgery.

Methods

Seventy patients of elective LC were included in this study. The patients were randomly assigned into two equal groups of propofol (75 µg/kg/min) and dexmedetomidine (0.5 µg/kg/hour) as anesthesia maintenance. Hemodynamic parameters (heart rate and mean atrial pressure), blood sugar, and serum epinephrine level were monitored and recorded from pre-anesthesia period to 10 min after entry to post-anesthesia care unit (PACU) according to a planned method.

Results

Heart rate and mean atrial pressure changes were significantly lower in dexmedetomidine group in all stages compared to propofol group (P < 0.001). Also, the rises in blood glucose and serum epinephrine levels in the dexmedetomidine group were significantly higher than in the propofol group (P < 0.001).

Conclusions

Anesthesia maintenance by dexmedetomidine showed a significant difference in hemodynamic parameters in comparison with propofol. While dexmedetomidine had better effects on controlling hemodynamic parameters, propofol showed better effects on decreasing stress hormones, and it can be suggested for LC surgery.

Practical Considerations for Dexmedetomidine Sedation in Adult Cataract Surgery Under Local/Regional Anesthesia: A Narrative Review

Cataract surgery is predominantly performed under local/regional anesthesia, with or without sedation. The practice pattern of sedation is unknown and seems to vary significantly among institutions and countries, routinely administered in some parts of the world to the other extreme of none at all. The selection of sedative agents and techniques varies widely. Currently, there is no ideal sedative agent. Dexmedetomidine has gained recent attention for sedation in ophthalmic local/regional anesthesia due to its alleged advantages of effective sedation with minimal respiratory depression, decreased intraocular pressure, and reduced pain during the local anesthetic injection; however, they are subject to differing interpretations. Published literature also suggests that although dexmedetomidine sedation for cataract surgery under local/regional anesthesia is potentially useful, its role may be limited due to logistical difficulties in administering the recommended dose.

Effect of Different Loading Doses of Dexmedetomidine on Controlled Hypotension and the Incidence of Bradycardia During Rhinoplasty: A Clinical Trial

Controlled hypotension, with a mean arterial pressure (MAP) of 60 mmHg - 70 mmHg, provides a bloodless and visible surgical field during rhinoplasty. It has been shown that dexmedetomidine, an α2-adrenoreceptor agonist, is a suitable choice in this regard. One of the disadvantages of this drug is the possibility of severe bradycardia during infusion. Therefore, we compared lower intravenous (IV) loading doses to determine whether the hypotensive effect of the drug was preserved and the bradycardia incidence decreased. In this randomized, double-blinded clinical trial, 81 patients aged 18 to 50 years with the American Society of Anesthesiologists physical status (ASA-PS) class I and II, scheduled for rhinoplasty randomly received 1.0, 0.9, and 0.8 µg/kg (named as groups 1.0, 0.9, and 0.8, respectively) of IV dexmedetomidine before the induction of anesthesia followed by infusion (0.3 - 0.7 µg/kg/h) during operation. The patients' heart rate (HR), MAP, the requirements for nitroglycerin (NTG) and extra fentanyl, as well as the incidence of bradycardia, were recorded. Bleeding and visibility of the surgical field were scored by the surgeon using a 6-point visual scale. MAPs, HRs, and consumption of NTG and extra fentanyl were similar in the studied groups. The surgical field was more visible and bloodless in group 1.0 compared to group 0.8 (P < 0.001); the differences were not significant between groups 1.0 and 0.9 (P = 0.605). The incidence (P = 0.027) and the severity of bradycardia (P = 0.017) were higher in the groups with higher loading doses. We concluded that dexmedetomidine is an acceptable agent to provide controlled hypotension. A loading dose of 0.9 µg/kg, but not 0.8 µg/kg, provides similar surgical field conditions as the dose of 1 µg/kg. Furthermore, despite the decrease in the incidence of bradycardia, the hypotensive effect of the drug is preserved.