The Mutational Profile of Unicystic Ameloblastoma.

BRAF V600E is the most common mutation in conventional ameloblastoma (AM) of the mandible. In contrast, maxillary AMs appear to harbor more frequently RAS, FGFR2, or SMO mutations. Unicystic ameloblastoma (UAM) is considered a less aggressive variant of ameloblastoma, amenable to more conservative treatment, and classified as a distinct entity. The aim of this study was to characterize the mutation profile of UAM ( n = 39) and to compare it to conventional AM ( n = 39). The associations between mutation status and recurrence probability were also analyzed. In the mandible, 94% of UAMs (29/31, including 8/8 luminal, 6/8 intraluminal, and 15/15 mural subtypes) and 74% of AMs (28/38) revealed BRAF V600E mutations. Among the BRAF wild-type cases, 1 UAM showed a missense SMO mutation (p.L412F), whereas 2 NRAS (p.Q61R), 2 HRAS (p.Q61R), and 2 FGFR2 (p.C383R) activating mutations were identified in AM. Of the 3 maxillary UAMs, only 1 revealed a BRAF V600E mutation. Taken together, our findings demonstrate high frequency of activating BRAF V600E mutations in both UAM and AM of the mandible. In maxillary UAMs, the BRAF V600E mutation prevalence appears to be lower as was shown for AM previously. It could therefore be argued that UAM and AM are part of the spectrum of the same disease. AMs without BRAF V600E mutations were associated with an increased rate of local recurrence ( P = 0.0003), which might indicate that routine mutation testing also has an impact on prognosis.

Prolonged-release oxycodone/naloxone in postoperative pain management: from a randomized clinical trial to usual clinical practice.

OBJECTIVE: These studies evaluated the feasibility of using oral prolonged-release oxycodone/naloxone (OXN PR) for the management of acute postoperative pain. METHODS: Three studies were undertaken: (i) the analgesic efficacy of OXN PR was compared with prolonged-release oxycodone (OXY PR) in patients with knee arthroplasty in an immediate postoperative period (IPOP) study; (ii) OXN PR treatment was compared with other opioids during rehabilitation after knee arthroplasty in a noninterventional study (NIS); and (iii) surgical patients on other opioids were switched to OXN PR postoperatively during a quality improvement programme (QIP). RESULTS: In the IPOP study, the pain intensity at rest score decreased by a similar amount in the OXN PR and OXY PR groups, indicating similar analgesic efficacies. In the NIS, patient assessments indicated enhanced efficacy and tolerability for OXN PR compared with other opioids. The QIP indicated significant improvements in bowel function and less difficulty passing urine at the end of OXN PR treatment compared with baseline. No safety concerns were raised. CONCLUSIONS: The analgesic efficacies of OXN PR and OXY PR were similar in postoperative pain settings. OXN PR reduced the degree of restriction in relation to patients carrying out physiotherapy compared with other opioids, and improved bowel and bladder function.

Comparison of intrathecal morphine and continuous femoral 3-in-1 block for pain after major knee surgery under spinal anaesthesia.

Major knee surgery is associated with moderate or severe post-operative pain. Intrathecal morphine and continuous femoral 3-in-1 block were compared prospectively in 40 patients for pain after major knee surgery under spinal anaesthesia, with 4 mL isobaric 0.5% bupivacaine. In a random order, 20 patients received preservative free morphine 0.3 mg mixed with spinal bupivacaine. In 20 patients, following spinal anaesthesia with only bupivacaine, femoral 3-in-1 block was performed post-operatively with 0.5% bupivacaine 2 mg kg-1. The block was continued via a catheter with 0.25% bupivacaine 0.1 mL h-1 kg-1 until the next morning (24 h after induction of spinal anaesthesia). Intramuscular oxycodone was given as a rescue analgesic in all patients. Two patients from the femoral group were excluded due to technical failure. Three patients in the morphine group and one patient in the femoral group did not need any additional oxycodone. In the morphine group on average 2.8 (range 0-7) and in the femoral group 3.2 (0-5) additional doses of oxycodone were needed during the 24 h observation period. The mean pain scores were significantly lower in the morphine group at 9 and 12 h into the 24-h trial. Itching was seen only in the morphine group (40% of the patients). Other side effects were similar in the two groups. All patients were satisfied with their pain therapy. Both intrathecal morphine and femoral 3-in-1 block alone were insufficient for the treatment of severe pain after major knee surgery.

Home-readiness after spinal anaesthesia with small doses of hyperbaric 0.5% bupivacaine.

Fifty-four patients were studied prospectively to evaluate home-readiness after a small dose (1 or 2 ml) of subarachnoid hyperbaric 0.5% bupivacaine. The block regressed significantly earlier in the 1 ml group than in the 2 ml group (p < 0.05). The patients were also able to walk significantly earlier in the 1 ml group (median 161 min and 231 min in the 1 ml and 2 ml groups, respectively) (p < 0.05). However, there were no significant differences between the groups in time of ability to void. We conclude that adequate surgical anaesthesia can be achieved with small doses of hyperbaric bupivacaine used for spinal anaesthesia. Although the sensory and motor block after 1 or 2 ml hyperbaric bupivacaine recovered within a reasonable time for day-case surgery, in some patients recovery of the ability to void was delayed to an undesirable extent.

Transient radicular irritation after bupivacaine spinal anesthesia.

BACKGROUND AND OBJECTIVES: Transient radicular irritation (TRI) has been described to occur following spinal anesthesia with hyperbaric 5% lidocaine. The authors recently used only isobaric or hyperbaric 0.5% bupivacaine for spinal anesthesia. All patients who had spinal anesthesia for various kinds of surgery were interviewed after the operation to discover the possibility of TRI following bupivacaine spinal anesthesia. METHODS: The study included 226 patients. Isobaric 0.5% bupivacaine was given to 116 patients and hyperbaric 0.5% bupivacaine to 110. The local anesthetic was chosen according to the expected duration of surgery. All patients were interviewed by an anesthesiologist 24 hours after spinal anesthesia, and after 1 week the patients were asked to return a written questionnaire. If pain not associated with operation was noted, the patients were interviewed by phone. RESULTS: One 48-year-old woman reported TRI after spinal anesthesia (saddle block) with hyperbaric 0.5% bupivacaine in the 24-hour interview. Her spinal anesthetic was performed in a sitting position and the anal surgery in a lithotomy position. In the 1-week questionnaire (response rate 92%), none of the other patients fulfilled our criteria for TRI. CONCLUSIONS: In spite of one case of TRI, the authors consider bupivacaine to be safe for spinal anesthesia. The association of the sitting and lithotomy positions to the restricted distribution of hyperbaric solution and consequent TRI warrants further studies.

Transient radicular irritation after spinal anaesthesia with hyperbaric 5% lignocaine.

We have studied prospectively 600 patients who had spinal anaesthesia for minor surgery, to evaluate the incidence of transient radicular irritation after the block. The anaesthetic agent (hyperbaric 5% lignocaine, hyperbaric 0.5% bupivacaine or plain 0.5% bupivacaine) was chosen according to the anticipated duration of surgery. We obtained information after operation from 537 patients (282 by telephone, 255 by letter). Ten percent of patients anaesthetized with hyperbaric 5% lignocaine (27 patients) had transient bilateral radiating pain in the lower extremities, buttocks, or both. Typically the pain started within 24 h after spinal anaesthesia, lasted less than 2 days and was described as mild. Lignocaine was the only variable that correlated with this pain. Two patients complained of symptoms after hyperbaric 0.5% bupivacaine but these were atypical compared with pain after lignocaine. None of the patients anaesthetized with plain bupivacaine had similar complaints. We conclude that the use of 5% hyperbaric lignocaine for spinal anaesthesia should be reconsidered.

Difficulties in spinal needle use. Insertion characteristics and failure rates associated with 25-, 27- and 29-gauge Quincke-type spinal needles.

The effect of different size (25-, 27- and 29-gauge) Quincke-type spinal needles on the incidence of insertion difficulties and failure rates was investigated in a randomised, prospective study with 300 patients. The needle size was randomised but the insertion procedure was standardised. The time to achieve dural puncture was significantly longer with the 29-gauge spinal needle compared with the larger bore needles and was due to the greater flexibility of the thin needle. However, the difference was less than 1 min and cannot be considered clinically significant. There were no significant differences between groups in the number of insertion attempts or failures and the same sensory level of analgesia was reached with all the needle sizes studied. Postoperatively, no postdural puncture headaches occurred in the 29-gauge spinal needle group, whilst in the 25- and 27-gauge needle groups, the postdural puncture headache rates were 7.4% and 2.1% respectively. The incidence of backache was similar in all study groups. We conclude that dural puncture with a 29-gauge spinal needle is clinically as easy as with larger bore needles and its use is indicated in patients who have a high risk of postdural puncture headache.