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D Shlugman

Publications and source records attributed to D Shlugman.

9 recordsLinked to original sources

Sub-Tenon's block reduces both intraoperative and postoperative analgesia requirement in vitreo-retinal surgery under general anaesthesia.

BACKGROUND AND OBJECTIVE: We compared the effects of sub-Tenon's local anaesthetic block and placebo on peri-operative opioid requirement and cardiovascular stability and on postoperative pain, nausea and vomiting in patients undergoing vitreo-retinal surgery under general anaesthesia. METHODS: We studied 43 patients undergoing vitreo-retinal surgery under general anaesthesia in a randomized double blind study. Patients received a standard general anaesthetic followed by a sub-Tenon's injection of 4-5 mL of either bupivacaine 0.75% or saline. We recorded intraoperative invasive arterial pressure, then the incidence and severity of pain and of nausea and vomiting, for 24 h postoperatively. RESULTS: In the sub-Tenon's bupivacaine group, there was a significant reduction in the perioperative opioid use and a reduction in the frequency of bradycardia and hypertensive episodes, defined as a rise > 25% of baseline for a duration of > 3 min. The sub-Tenon's bupivacaine group also had significantly lower pain scores and nausea scores at 12 h, concomitant with a lower consumption of analgesia and antiemetics. CONCLUSIONS: This local anaesthetic technique is effective in vitreo-retinal surgery and can be safely applied to this population of patients regardless of axial length.

Acetaminophen↗

Acute fatal haemorrhage during percutaneous dilatational tracheostomy.

Percutaneous dilatational tracheostomy (PDT) is associated with a number of life-threatening complications. We present a case of massive and fatal arterial haemorrhage that occurred in the intensive care unit during an elective PDT on an 86-year-old woman following earlier evacuation of a traumatic subdural haematoma. An avulsed right subclavian artery was found at post mortem. Previous thyroid surgery and aberrant arterial anatomy contributed to the fatal outcome.

Aged↗

How high do the subclavian arteries ascend into the neck? A population study using magnetic resonance imaging.

BACKGROUND: The relationship between the larynx and the subclavian arteries was studied in a series of magnetic resonance images (MRIs) from 50 patients without neck pathology. METHODS: The vertical distances of the excursion of the subclavian arteries into the neck was measured, as was the distance from the cricoid cartilage to the highest point of this excursion. Statistical analysis allows the probability of any given cricoid-subclavian distance occurring in the population to be estimated. RESULTS: The mean (SD) excursion of the right subclavian artery above the clavicle was 10.4 (11.4) mm. The mean (SD) distance from the cricoid cartilage to the right subclavian artery was 30.6 (14.3) mm, and the data showed a high degree of variance. There was a linear relationship between neck length and cricoid-subclavian distance (r=0.58), which explained some of the variance in the latter, but there was also wide individual variance, which was independent of this regression. CONCLUSIONS: When performing a percutaneous tracheostomy, a 'safe' distance between the incision site and subclavian artery cannot be assumed or reliably predicted from the neck length.

Cricoid Cartilage↗

Abnormal pupillary activity in a brainstem-dead patient.

The pupils in brainstem-dead patients are classically fixed and dilated. We present a case of a brainstem-dead patient whose pupils displayed persistent asynchronous pupillary constriction and dilatation independent of external physical stimuli. Central causes for the phenomenon were excluded leaving an unexplained peripheral cause as the most likely explanation. Early recognition of this phenomenon prevents delay in the diagnosis of brainstem death, lessening to some extent the distress for the family, and facilitating earlier organ donation and allowing the better use of resources.

Adult↗

Motor cortex stimulation for chronic neuropathic pain: a preliminary study of 10 cases.

There is growing evidence to support the use of motor cortex stimulation (MCS) in the management of patients with chronic neuropathic pain. A prospective audit of ten patients using a modified staged technique for motor cortex implantation provides further evidence for the analgesic effectiveness of this technique. Ten patients suffering from phantom limb pain (n=3), post stroke pain (n=5), post traumatic neuralgia secondary to gunshot injury to the brain stem (n=1) and brachyalgia secondary to neuro-fibromatosis (n=150% pain relief) and long-term benefit in 4/5 of patients who initially responded to intermittent cortical stimulation (longest follow up 31 months after implantation). Of those patients who benefited two had post stroke pain, two phantom limb pain and one post-traumatic neuralgia. We conclude that motor cortex stimulation is an effective analgesic intervention in some patients with chronic neuropathic pain, but it is difficult if not impossible to predict those patients who may respond to treatment prior to implantation. Randomised controlled trials are now urgently needed to test the effectiveness of motor cortex stimulation under double-blind conditions.

Adult↗

Pharmacokinetics and pharmacodynamics of remifentanil in persons with renal failure compared with healthy volunteers.

BACKGROUND: Remifentanil is an opioid analgesic for use in anesthesia. An ester linkage renders it susceptible to rapid metabolism by blood and tissue esterases. Thus it was hypothesized that remifentanil elimination would be independent of renal function. Because its principal metabolite (GR90291) is eliminated renally, it would depend on renal function. This study was designed to evaluate the pharmacokinetics and pharmacodynamics of remifentanil and its metabolite in persons with and without renal failure. METHODS: Two groups of volunteers received two-stage infusions of remifentanil: low dose with 0.0125 microg x kg(-1) x min(-1) for 1 h followed by 0.025 microg x kg(-1) x min(-1) for 3 h; and high dose with 0.025 microg x kg(-1) x min(-1) for 1 h followed by 0.05 microg x kg(-1) x min(-1) for 3 h. Blood samples were collected for analysis of remifentanil and GR90291 concentrations. The pharmacokinetics of remifentanil were fit using a one-compartment pharmacokinetic model. Remifentanil's effect was determined intermittently using minute ventilation during a hypercapnic (7.5% CO2) challenge. RESULTS: Fifteen patients with renal failure and eight control participants were enrolled. The clearance and volume of distribution of remifentanil were not different between those with renal failure and the controls. Patients with renal failure showed a marked reduction in the elimination of GR90291; the half-life of the metabolite increased from 1.5 h in the controls to more than 26 h in patients with renal failure. The steady-state concentration of GR90291 is likely to be more than 25 times higher in persons with renal failure. There were no obvious differences in opioid effects on minute ventilation in the controls and in patients with renal failure. CONCLUSIONS: The pharmacokinetics and pharmacodynamics of remifentanil were not altered in patients with renal disease, but the elimination of its principal metabolite, GR90291, was markedly reduced. Based on simulations, the concentration of GR90291 at the end of a 12-h remifentanil infusion of 2 microg x kg(-1) x min(-1) is not likely to produce significant opioid effects.

Analgesics, Opioid↗

Reduction of isoflurane minimal alveolar concentration by remifentanil.

BACKGROUND: Remifentanil is a new micro-specific opioid receptor agonist currently under investigation. The interaction between opioids and volatile anesthetics is complex. Defining this interaction provides a basis for more rational dosing schemes when such combinations are used for anesthesia and allows the anesthetic potency of remifentanil relative to other opioids to be determined. METHODS: Two centers enrolled a total of 220 patients. Patients were randomized to receive a target concentration of remifentanil via a computer-assisted continuous infusion device of either 0.0, 0.5, 1.0, 1.5, 2.0, 4.0, 8.0, 16.0, and 32.0 ng/ml initiated before the administration of isoflurane. Patients were also stratified by groups 18-30, 31-55, and 56-65 yr. After induction of anesthesia with isoflurane the initial patient in each dose group was assigned an age-adjusted isoflurane concentration. The isoflurane concentration for each subsequent patient was adjusted according to the up/down technique until a minimum of 12 patients were enrolled in each group. Arterial blood samples for remifentanil whole blood concentrations were obtained. The patient was observed for purposeful movement for up to 1 min after skin incision. The minimum alveolar concentration (MAC) of isoflurane (0 ng/ml remifentanil group) and MAC reduction of isoflurane by remifentanil were determined. RESULTS: The MAC of isoflurane alone was 1.3%. Remifentanil caused an exponential reduction in the MAC of isoflurane with 1.37 ng/ml remifentanil a 77% reduction and 32 ng/ml a 91% reduction of isoflurane MAC. CONCLUSION: The MAC reduction of isoflurane by remifentanil is similar to that produced by other opioids. Although remifentanil was given at extremely high concentrations in the absence of isoflurane, it did not provide adequate anesthesia. A 50% isoflurane MAC reduction is produced by 1.37 ng/ml remifentanil whole blood concentration compared to previously published plasma concentrations of fentanyl of 1.67 ng/ml or sufentanil of 0.14 ng/ml.

Adolescent↗

Transkei foot.

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Adult↗