Lucy Chan

A randomised comparison of two intranasal dexmedetomidine doses for premedication in children

We compared sedation levels in children following administration of intranasal dexmedetomidine. One hundred and sixteen children aged between 1 and 8 years were enrolled in this prospective, randomised trial. Children were assigned to receive either intranasal dexmedetomidine 1 μg.kg−1 (Group 1) or 2 μg.kg−1 (Group 2). Thirty‐one (53%) patients from Group 1 and 38 (66%) patients from Group 2 were satisfactorily sedated at the time of anaesthetic induction. Logistic regression showed a significant interaction effect (p = 0.049), with the odds ratio between Group 2 over Group 1 estimated as 1.1 (95% CI 0.5–2.7) for the 1–4 year age group, and 10.5 (95% CI 1.4–80.2) for the 5–8 year age group. Both doses produced a similar level of satisfactory sedation in children aged 1–4 years, whereas 2 μg.kg−1 resulted in a higher proportion of satisfactory sedation in children aged 5–8 years. There were no adverse haemodynamic effects. We conclude that intranasal dexmedetomidine in a premedication dose of 2 μg.kg−1 resulted in excellent sedation in children.

The effects of staged intra-articular injection of cultured autologous mesenchymal stromal cells on the repair of damaged cartilage: a pilot study in caprine model

IntroductionTreatment of chondral injuries remains a major issue despite the many advances made in cartilage repair techniques. Although it has been postulated that the use of marrow stimulation in combination with cell-based therapy may provide superior outcome, this has yet to be demonstrated. A pilot study was thus conducted to determine if bone marrow derived mesenchymal stromal cells (BM-MSCs) have modulatory effects on the repair outcomes of bone marrow stimulation (BMS) techniques.MethodsTwo full-thickness chondral 5 mm diameter defects were created in tandem on the medial condyle of left stifle joints of 18 Boer caprine (N = 18). Goats were then divided equally into three groups. Simultaneously, bone marrow aspirates were taken from the iliac crests from the goats in Group 1 and were sent for BM-MSC isolation and expansion in vitro. Six weeks later, BMS surgery, which involves subchondral drilling at the defect sites, was performed. After two weeks, the knees in Group 1 were given autologous intra-articular BM-MSCs (N = 6). In Group 2, although BMS was performed there were no supplementations provided. In Group 3, no intervention was administered. The caprines were sacrificed after six months. Repairs were evaluated using macroscopic assessment through the International Cartilage Repair Society (ICRS) scoring, histologic grading by O’Driscoll score, biochemical assays for glycosaminoglycans (GAGs) and gene expressions for aggrecan, collagen II and Sox9.ResultsHistological and immunohistochemical analyses demonstrated hyaline-like cartilage regeneration in the transplanted sites particularly in Group 1. In contrast, tissues in Groups 2 and 3 demonstrated mainly fibrocartilage. The highest ICRS and O’Driscoll scorings was also observed in Group 1, while the lowest score was seen in Group 3. Similarly, the total GAG/total protein as well as chondrogenic gene levels were expressed in the same order, that is highest in Group 1 while the lowest in Group three. Significant differences between these 3 groups were observed (P <0.05).ConclusionsThis study suggests that supplementing intra-articular injections of BM-MSCs following BMS knee surgery provides superior cartilage repair outcomes.

Magnetic Resonance Imaging of Asians with Multiple Sclerosis was similar to that of the West.

Magnetic resonance imaging (MRI) of the brain is the most important paraclinical diagnostic test in multiple sclerosis (MS). The appearance of MRI in Asians with MS is not well defined. We retrospectively surveyed the first brain and spinal cord MRI in patients diagnosed to have MS, according to Posers criteria in seven regions throughout Asia to define the MRI changes among Asians with MS. There were 101 patients with first brain, and 86 with first spinal cord MRI, 66 of whom had both. The brain MRI showed a mean of 17 lesions per patient in T2 weighted images, mostly asymptomatic. Almost all the lesions were in the white matter, particularly in the juxtacortical, deep and periventricular white matter. A third of the lesions were greater than 5 mm, 14% enhanced with gadolinium. There were more supratentorial than infratentorial lesions at a ratio of 7.5: 1. Ninety five percent of the spinal cord lesions were in cervical and thoracic regions, 34% enhanced with gadolinium. The lesions extended over a mean of 3.6 +/- 3.3 vertebral bodies in length. Fifty (50%) of the brain and 54 (63%) of the spinal MRI patients had the optic-spinal form of MS. The MRI of the optic-spinal and classical groups of patients were similar in appearance and distribution, except that the optic-spinal MS patients have fewer brain but longer and more severe spinal cord lesions. In conclusion, the brain and spinal cord MRI of Asian patients with MS was similar to that of the West, although, in this study, Asian MS patients had larger spinal cord lesions.

Postoperative sore throat and ketamine gargle

Editor—We investigated, in a double-blind randomized control study, the effect of a ketamine gargle to attenuate postoperative sore throat (POST) in 44 adult ASA I or II patients undergoing elective gynaecological procedures. The patients had 30 s gargling with either 20 ml of normal saline (Group C: control, n1⁄422) or ketamine 40 mg in 20 ml normal saline (Group K: ketamine, n1⁄422). Anaesthesia was induced with fentanyl, propofol, and rocuronium, 5–10 min after gargling. Maintenance of anaesthesia was with oxygen–air mixture and sevoflurane. Titrated boluses of morphine were given according to clinical requirements during surgery. The same anaesthetist performed all intubations and extubations. During surgery, blood samples were collected at intervals for ketamine and norketamine analysis. At the end of the study period, serum samples from five patients in Group K, randomly selected, were assayed by liquid chromatography and mass spectrometry. After extubation, POST was assessed at 0 (on arrival at the post-anaesthetic care unit), 2, and 24 h using a four-point grading scale (none, 0; mild, 1; moderate, 2; and severe, 3). POST was significantly reduced in Group K compared with Group C (P,0.05) at 0 and 2 h after surgery but not at 24 h (P1⁄40.498). There was significantly less moderate-to-severe POST in Group K at 0 h. Ketamine gargle has been reported to attenuate POST for 24 h post-surgery. We observed significant reduction in POST at 0 and 2 h post-surgery but not at 24 h. The reported ketamine level to relieve tourniquet pain after an i.v. bolus was .100 ng ml. The analgesic effect from oral administration of ketamine was at a lower mean plasma concentration of ketamine 40 ng ml, presumably due to the higher norketamine levels (160 ng ml). In this study, blood samples were obtained during intraoperatively, but POST was assessed post-surgery when ketamine concentrations are likely to be lower. Systemic absorption and the possibility of swallowing the residual solution would contribute to the ketamine in the blood. The highest average ketamine and norketamine concentrations, 16.16 and 11.43 ng ml, respectively (Table 1), were detected during surgery but would have decreased after the surgery. These low levels suggested that it was unlikely that systemic absorption played a major role for the reduction of POST. A topical effect is possible. We conclude that pre-induction ketamine gargle can attenuate POST in the early postoperative period. Drug levels detected were much lower than reported measurements for analgesia after oral and parenteral administration.

Comparing the efficacy and safety between propofol and dexmedetomidine for sedation in claustrophobic adults undergoing magnetic resonance imaging (PADAM trial)

STUDY OBJECTIVE To determine the efficacy of sedation with dexmedetomidine compared to propofol for claustrophobic adults undergoing magnetic resonance imaging (MRI) in our institution. DESIGN Randomized, prospective, double-blinded study. SETTING University-based tertiary referral center. PATIENTS Thirty claustrophobic adults with American Society of Anesthesiologists physical status I and II who were planned for MRI. INTERVENTIONS Patients were randomly assigned to target-controlled infusion propofol or dexmedetomidine loading followed by maintenance dose for procedural sedation. MEASUREMENTS AND MAIN RESULTS The primary end point was adequate reduction in patient anxiety levels to allow successful completion of the MRI sequence. Both methods of sedation adequately reduced anxiety levels in visual analog scale scores and Spielberger Strait Test Anxiety Inventory (P<.001). Dexmedetomidine required a longer time to achieve anxiolysis, 7.36minutes (SD, 2.59), and required increasing maintenance dose to induce sleep compared to 10.71minutes (SD, 4.63) for propofol. In terms of image quality, 2 patients (16.67%) in the dexmedetomidine group were satisfactory, whereas all with propofol were graded as good to excellent. Adverse effects were seen in patients sedated with dexmedetomidine with number needed to harm 8 for hypotension and 15 for bradycardia compared to none recorded in the propofol arm. There was no significant difference in patient satisfaction scores or home readiness after the MRI. CONCLUSIONS Both dexmedetomidine and propofol can effectively reduce anxiety levels of claustrophobic adults undergoing MRI, but dexmedetomidine takes longer to achieve adequate anxiolysis and sleep and may have an effect on image quality. Hypotension and bradycardia are common adverse effects observed with dexmedetomidine.

Children with anterior mediastinal mass:procedural sedation with dexmedetomidine

In view of inconclusive peripheral blood film and fine needle aspiration cytology results, a lymph node biopsy was needed. Under dexmedetomidine sedation, an ultrasound-guided right SCPB was performed. Standard monitors were applied and his respiratory rate and depth of respiration were closely observed. A loading dose of dexmedetomidine 1mg kg 1 was given intravenously over 10 min followed by a maintenance infusion of 0.5–1mg kg 1 per h. He was positioned supine for the procedure. With ultrasound guidance and out-of-plane

Herniação cerebral intratável secundária a pneumoencéfalo hipertensivo no intraoperatório: uma complicação rara com risco para a vida durante a drenagem de empiema subdural

Tension pneumocephalus is rare but has been well documented following trauma and neurosurgical procedures. It is a surgical emergency as it can lead to neurological deterioration, brainstem herniation and death. Unlike previous cases where tension pneumocephalus developed postoperatively, we describe a case of intraoperative tension pneumocephalus leading to sudden, massive open brain herniation out of the craniotomy site. The possible causative factors are outlined. It is imperative to rapidly identify possible causes of acute intraoperative brain herniation, including tension pneumocephalus, and institute appropriate measures to minimize neurological damage.

Anestesia em encefalite antirreceptor de N‐metil‐d‐aspartato – a anestesia geral é um requisito? Relato de caso

Anti-N-methyl-d-aspartate receptor encephalitis is a recently described neurological disorder and an increasingly recognized cause of psychosis, movement disorders and autonomic dysfunction. We report 20-year-old Chinese female who presented with generalized tonic-clonic seizures, recent memory loss, visual hallucinations and abnormal behavior. Anti-N-methyl-d-aspartate receptor encephalitis was diagnosed and a computed tomography scan of abdomen reviewed a left adnexal tumor. We describe the first such case report of a patient with anti-N-methyl-d-aspartate receptor encephalitis who was given a bilateral transversus abdominis plane block as the sole anesthetic for removal of ovarian tumor. We also discuss the anesthetic issues associated with anti-N-methyl-d-aspartate receptor encephalitis. As discovery of tumor and its removal is the focus of initial treatment in this group of patients, anesthetists will encounter more such cases in the near future.

Anesthetic Challenges in Pediatric Craniofacial Surgeries

Pediatric syndromic and nonsyndromic craniofacial abnormalities require close collaboration among experts in an institution with facilities for perioperative care. In severe cases from an early stage of life, children display structural alterations in the cranial vault, face, orbits, and jaw that have an impact on related functions. Craniofacial surgeries can improve both form and function and are performed electively from less than a year old. Urgent interventions may be necessary to address critical events such as tracheostomy for an obstructed airway or ventriculo-peritoneal shunt for severely elevated intracranial pressure.

In vitro and in vivo Evaluation of New Topical Anaesthetic Cream Formulated with Palm Oil Base.

BACKGROUND Topical local anaesthetic cream was reported to be useful for pain relief for cutaneous procedures such as minor surgery and venipuncture. OBJECTIVE The aim of this study was to evaluate the effectiveness of new formulation of lidocaine topical anaesthetic using palm oil base, HAMIN® and to determine how fast this new formulation produces adequate numbness compared to the currently used EMLA cream, in the University of Malaya Medical Centre (UMMC) set-up. METHOD The skin permeation test was conducted by using Franz type diffusion cell and pain assessment was carried out in healthy subject by using Verbal Rating Score (VRS) and Visual Analogue Score (VAS) evaluation. RESULT Result of permeation test demonstrated that the cumulative amount of lidocaine released from HAMIN® cream was increased with time and slightly higher than EMLA cream. The clinical study showed that HAMIN® single lidocaine cream can produces numbness through venepuncture procedure and comparable with EMLA cream which is a combination therapy for local anaesthetic (lidocaine and prilocaine). CONCLUSION It can be concluded that HAMIN® Lidocaine cream is suitable for cream preparation especially for topical application and it can be regarded as an achievement in palm oil and medical industries.