Use of Dexmedetomidine in a Patient Allergic to Clonidine Presenting for an Awake Craniotomy: A Case Report

Introduction: The use of dexmedetomidine with concurrent scalp block is increasingly being utilized as an effective and safe anesthetic approach for awake craniotomy (AC). Dexmedetomidine is an alpha-2 adrenergic receptor (α2-AR) agonist with dose-dependent sedative, analgesic, and anxiolytic properties while preserving respiratory function. The challenge with the use of dexmedetomidine arises when the patient in question has a clonidine allergy that is also an α2-AR agonist. Currently there aren’t any published literature regarding the use of dexmedetomidine in a patient allergic to clonidine. Case Presentation: A 48-year-old male with chronic obstructive pulmonary disease, obstructive sleep apnea, and body mass index of 54 with clonidine allergy presents for an AC. Given the goals of the surgery and patient comorbidities, we planned for monitored anesthesia care with intravenous (IV) dexmedetomidine, remifentanil, and propofol. We discussed the use of dexmedetomidine with the patient and the potential risk of allergic reaction given his allergy to clonidine. Patient understood the risk and consented to the anesthetic plan. AC was successfully performed with IV dexmedetomidine, remifentanil, and propofol.Conclusion: Although both dexmedetomidine and clonidine have some functional similarities in terms of acting on the central and peripheral nervous system, there are marked differences between the two based on chemical structure, receptor affinity, and metabolism of the drug. This case highlights the successful use of dexmedetomidine in a patient with known allergy of rash to clonidine.

Regional scalp block – the key analgesic element of anesthesia for supratentorial craniotomy

This paper presents the key data on the effectiveness and safety of the regional anesthesia of the scalp, also known as the scalp block, for providing perioperative analgesia for supratentorial craniotomy. The authors describe the technique and its limitations and also trace the implementation of the scalp block method into the routine practice of the largest Russian neurosurgical clinic based on personal experience, results of the own research, and analysis of literature data.

Anaesthetic Management of Left Temporal Glioma Undergoing Awake Craniotomy

For an awake craniotomy, a 49 year old (ASA 2), 78 kg woman with type II DM was given regional anaesthesia (scalp block) with monitored anaesthesia care (MAC). She had a headache, which was primarily caused by a left temporal glioma. She was very apprehensive about having this procedure done while she was awake. Fentanyl and Dexmedetomidine infusions in combination with scalp block initially provided adequate operating conditions. Because the patient needed to be fully awake, alert and cooperative during the language and motor mapping, all sedation was turned off. Patient was cooperative and obeyed commands during motor and language mapping as well as during tumour excision. Patient underwent complete excision of tumour without any postoperative neurological deficit. The success of the awake craniotomy is dependent on the patient cooperation, anaesthesiologist's experience, adequate intraoperative analgesia coverage, careful sedation titration, and meticulous planning.

Perbedaan Respon Hemodinamik terhadap Penambahan Clonidin 1 dan 2 mcg/kgbb pada Scalp Block untuk Operasi Kraniotomi

Bacground and Objective: The addition of a levobupivacaine scalp block is effective in reducing hemodynamic responses such as blood pressure, mean arterial pressure (MAP) and pulse rate, especially when pinning, skin incisions, and durameter incisions in craniotomy. Adjuvants are often added to local anesthetics to enhance and prolong the analgesic effect of peripheral nerve blocks. Clonidine has a synergistic action with local anesthetic agents. Clonidine increases sensory and motor blocks in both peripheral and neuraxial blocks. The common dose is 2 mcg/kgbw. The aim of this study was to determine the effectiveness of adding clonidine 2 mcg/kg and 1 mcg/kg on scalp block as craniotomy analgesic. Subjects and Methods: Study on 30 patients met the inclusion criteria. Subjects were divided into three groups, group I: scalp block with levobupivacain 0.25%, group II: scalp block plus clonidine 1 mcg/kg, group III: scalp block plus clonidine 2mcg/kg. All patients were treated with general anesthesia according to the standard then assessed their blood pressure, MAP, pulse rate before intubation, pinning, skin incision and duramater incision. Results: There was a significant difference in the addition of clonidine with the control group, especially in the pulse and diastolic rates. Clonidine 2 mcg/kg at several times showed a significant difference compared to 1 mcg/kgbb dose. Conclusion: The clonidine addition to scalp block of levobupivacaine was effective in maintening hemodynamic responses, especially pulse rate and diastolic blood pressure.

Influence of scalp block on oncological outcomes of high-grade glioma in adult patients with and without isocitrate dehydrogenase-1 mutation

High-grade gliomas are notorious for a high recurrence rate even after curative resection surgery. Studies regarding the influence of scalp block on high-grade gliomas have been inconclusive, possibly because the condition’s most important genetic mutation profile, namely the isocitrate dehydrogenase 1 (IDH1) mutation, had not been analyzed. Therefore, we conducted a single-center study including patients with high-grade glioma who underwent tumor resection between January 2014 and December 2019. Kaplan–Meier survival analysis revealed that scalp block was associated with longer progression-free survival (PFS; 15.17 vs. 10.77 months, p = 0.0018), as was the IDH1 mutation (37.37 vs. 10.90 months, p = 0.0149). Multivariate Cox regression analysis revealed that scalp block (hazard ratio: 0.436, 95% confidence interval: 0.236–0.807, p = 0.0082), gross total resection (hazard ratio: 0.405, 95% confidence interval: 0.227–0.721, p = 0.0021), and IDH1 mutation (hazard ratio: 0.304, 95% confidence interval: 0.118–0.784, p = 0.0138) were associated with better PFS. Our results demonstrate that application of scalp block, regardless of IDH1 profile, is an independent factor associated with longer PFS for patients with high-grade glioma.

Awake surgery for lesions near eloquent brain under scalp block and clinical monitoring: experience of single center with limited resources

Background Surgery of the brain tumors near eloquent areas carries the risk of either disabling neurological deficit or inadequate resection with bad prognosis in both situations. Awake surgery is the gold standard procedure for such lesions. However, it requires certain anesthetic drugs, advanced techniques, and trained teams that are not available in every neurosurgical institute. This work aims to evaluate safety, feasibility, and outcome of operating on patients with space occupying lesions near eloquent areas under scalp block being continuously examined by a neurologist through retrospective study of 20 cases with supratentorial lesions related to language or sensorimotor cortex. Results There were 12 males and 8 females with mean age 36.8 years. Forty percent of patients were presented by motor weakness. Tumors were related to motor cortex in 11 patients and to language areas in 9 patients. Mean operative time was 210 min. Gross or near total resection was achieved in 15cases, four cases had subtotal resection and biopsy only was done in 1 case. Two patients suffered from intraoperative seizures and conversion to general anesthesia was required in one patient. Conclusion Operating on tumors near eloquent brain areas under scalp block and continuous neurological examination during tumor resection proved to be effective in early detection and prevention of permanent major deficits especially in the developing countries with limited resources.