Accelerated reversal of atracurium blockade with divided doses of neostigmine

The hypothesis that administration of neostigmine in divided doses might accelerate the antagonism of neuromuscular blockade was investigated. Neostigmine 0.05 mg X kg-1 was administered either in a single bolus dose (Group I, n = 16) or in an initial dose of 0.01 mg X kg-1 followed three minutes later by 0.04 mg X kg-1 (Group II, n = 16) for antagonism of atracurium-induced blockade. Reversal was attempted at 10 per cent spontaneous recovery of twitch height. The mean time (+/- SD) from the first injection of the drug until the train-of-four (TOF) ratio value had reached 0.75 was significantly shorter in Group II (p less than 0.05) than in Group I (391.8 +/- 83.3 and 468.6 +/- 150.3 seconds respectively). The rate of TOF ratio recovery was 2.5 times faster after neostigmine administration in divided doses. It is concluded that administration of neostigmine in divided doses, as described in this study, produced a significantly faster reversal of residual atracurium-induced neuromuscular blockade as compared to a single bolus administration.     

Salsola pollen as a predominant cause of respiratory allergies in Kuwait.

BACKGROUND: Respiratory allergies are common in Kuwait, and the role of certain allergens has been previously documented. OBJECTIVE: To evaluate the results of skin prick tests to a range of allergens that were considered relevant to the vegetation surveys and aerobiological studies performed in Kuwait. METHOD: New patients attending our center during August 2002 to February 2003 with asthma or allergic rhinitis underwent skin prick tests to a battery of allergens. RESULTS: A total of 451 patients aged 5 to 60 years (mean age, 29.5 years) were tested. Of these patients, 403 (89.4%) had a positive test result to at least one allergen and were considered allergic. A total of 76.7% of the allergic patients had a positive reaction to Salsola pollen, with a mean wheal diameter of 8.25 mm (median, 8 mm). Chenopodium album was positive in 57.6% and Bermuda grass was positive in 38.2% of the allergic cases. Indoor allergens seemed to play a lesser role than pollens: Dermatophagoides pteronyssinus was positive in only 37.5%, and American and German cockroaches were positive in 33.2% and 22.3%, respectively. All the allergens other than Salsola elicited a mean wheal diameter of less than 6.25 mm (median, < or = 6 mm). CONCLUSIONS: Indoor allergens seem to play a lesser role in respiratory allergies in Kuwait. Most allergic patients become sensitized to pollens; the strongest and most frequent reaction is from Salsola pollen. Salsola imbricata is found growing extensively in most areas of the country, flowering mainly in autumn, when the most common pollen is of the Chenopod-Amaranth type and when most patients with seasonal allergic rhinitis become symptomatic.     

The response of a patient with von Recklinghausen's disease to succinylcholine and atracurium

The anesthetic management of a 17-year-old female with von Recklinghausen's disease (multiple neurofibromatosis) is described. Multiple neurofibromatosis is a rare syndrome characterized by abnormal cutaneous pigmentation and numerous skin tumors. In addition to the usual stigmata of the syndrome, patients with neurofibromatosis have been reported to be either sensitive or resistant to succinylcholine. Further, all reports indicate that response to nondepolarizing muscle relaxants is exaggerated. In this patient, the nerve conduction studies were within limit of normal values. During surgery, neuromuscular function was monitored throughout using the train-of-four mechanical twitch response. The response of this patient to succinylcholine was normal and the response to atracurium was slightly prolonged. It is concluded that atracurium offers advantages over the other nondepolarizing muscle relaxants in patients with von Recklinghausen's disease.     

Epidemiology and outcome of “Early-onset” vs “Late-onset” necrotizing enterocolitis

Objective: We hypothesized that among neonates with necrotizing entercolitis (NEC), important epidemiologic and outcome differences exist between those with early-onset vs. those with late-onset NEC.Methods : We reviewed all records of neonates cared for in the King Fahad University Hospital during the past ten years who had the diagnosis of NEC. We separated cases into two groups depending on age at diagnosis. Specifically, we termed “early-onset” those cases diagnosed during the first seven days of life, and “late-onset” those diagnosed thereafter. We compared, in the two groups, gestational age, clinical signs at onset, laboratory data, surgical findings, complications, and mortality.Results: From 1989 to 1999, 37 cases of stage lla (or higher) NEC were diagnosed; 25 “early-onset “ and 12 “late-onset”. Neonates with “earlyonset” NEC were more mature (35.4 ±2.5 weeks gestation) than those with “late-onset” (27.7 ±2.8 weeks, P = 0.0001), were more likely to have feedings begun in the first 48 hours of life (P = 0.0002), and more likely to have feeding increments of >25 ml/kg/day (P=0.03). Neonates with “late-onset” NEC were more likely to present with vomiting (P=0.003) and apnea (P=0.001), and were more likely to have ileal rather than colonic necrotic lesions, short bowel syndrome, and mortality (P = 0.03).Conclusion: During the past 10 years at the King Fahad University Hospital, cases of early and late-onset NEC have had distinct epidemiologic and outcome features. Recognizing these differences may be useful in prognostication and counseling     

Edrophonium antagonism of cisatracurium-induced neuromuscular block: dose requirements in children and adults

This randomized, controlled study compared edrophonium dose requirements to antagonize cisatracurium-induced neuromuscular block in children and adults. Sixty children, aged two to 10 years, and 60 adults aged 20 to 60 years, all subjects ASA physical status 1 or 2, having propofol, fentanyl and isoflurane-N2O anaesthesia, were studied. Cisatracurium 0.1 mg x kg(-1) was given for muscle relaxation. Neuromuscular block was monitored with accelerometry. Edrophonium 0.1, 0.2, 0.4 or 1 mg x kg(-1) or no anticholinesterase (controls) was given by random allocation to antagonize 90% neuromuscular block in each of the study groups (n=12). Atropine 5 to 10 microg x kg(-1) was given according to edrophonium dose. Onset time of cisatracurium-induced block in children was mean (SD) 2.4 (0.8) versus 4.1 (2.3) minutes in adults, P<0.01. The times to 10% spontaneous recovery of the first twitch (T1) were respectively, 28.4 (5.2) and 41.8 (6.1) minutes in children and adults, P<0.01. Spontaneous and antagonist assisted neuromuscular recovery was more rapid in children. Adequate neuromuscular recovery (train of four (TOF) ratio 80%) was achieved in children at 3 and 10 minutes after edrophonium 1.0 mg kg(-1) and 0.4 mg x kg(-1), respectively. A TOF ratio of 80% was not achieved, within 10 minutes, with any of the four dose levels of edrophonium in adults. The dose of edrophonium to achieve a TOF ratio of 80% (ED(TOF-80)) after 5 and 10 minutes in children were, respectively, mean (SD) 0.85 (0.38) and 0.38 (0.19) mg x kg(-1). The equivalent ED(TOF-80) in adults was outside the edrophonium dose range studied.     

Edrophonium priming alters the course of neuromuscular recovery from a pipecuronium neuromuscular blockade

This study was designed to investigate the effect of divided administration of edrophonium on the course of neuromuscular recovery from a pipecuronium neuromuscular blockade. During thiopentone-nitrous oxide-halothane anaesthesia 48 patients were given pipecuronium 70 micrograms.kg-1. Patients were randomly assigned to one of four groups (n = 12 in each) to receive either edrophonium 1 mg.kg-1 (Groups I and II) or edrophonium 0.75 mg.kg-1 (Groups III and IV). In Groups I and III (single-dose groups), edrophonium was administered as a single bolus dose. In Groups II and IV (divided-dose groups) edrophonium was administered as an initial dose of 0.25 mg.kg-1 followed three minutes later by either 0.75 or 0.50 mg.kg-1 respectively. Reversal was attempted at 20% spontaneous recovery of twitch height. Administration of edrophonium in divided doses (Groups II and IV) accelerated the reversal of the pipecuronium neuromuscular blockade. At ten minutes post-reversal, train-of-four (TOF) ratio recovery reached 0.75 or more in 12 (100%) and in ten (83%) patients in Groups II and IV respectively. Similarly, times to attain a TOF of 0.75 (SEM) were shorter in the divided-dose groups than in the single-dose groups (P less than 0.05), being 354.5 (38.7) and 398.3 (49.1) sec in Groups II and IV vs 705.4 (66.6) and 651.2 (54.3) sec in Groups I and III respectively. Time was counted from the first administration of edrophonium. It is concluded that administration of edrophonium in divided doses produced a faster reversal of residual pipecuronium-induced neuromuscular blockade than single bolus administration. Also, administration in divided doses reduced the requirements of edrophonium needed for reversal of pipecuronium neuromuscular blockade.     

Prevalence and causes of blindness & low vision; before and five years after 'VISION 2020' initiatives in Oman: a review

BACKGROUND: A prevalence survey of blindness and low vision was conducted in Oman in 2005. Here, we present the prevalence and determinants of blindness and low vision among the population >or= 40 years of age. The results are then compared with those of the survey in 1997 and the changes following the 'VISION 2020' initiatives are assessed. METHODS: The survey covered 24 randomly selected clusters (75 houses in each). Teams assessed the distance vision of subjects while wearing glasses. The ophthalmologists examined the anterior segment and fundus to determine the causes of disability. The visual field was tested in those suspected of glaucoma. The prevalence rates of blindness (< 3/60 on presentation), legal blindness (< 6/60) and low vision (< 6/18) were calculated. The data from the 1997 survey was then analyzed to obtain similar rates in the population >or= 40 years of age. RESULTS: The prevalence of blindness was 8.25% (95% CI 7.14-9.36) in the >or= 40 year-old population in 2005. The rate would be 6.95% (95% CI 5.92-7.98) if blindness were defined as vision with best possible correction. The prevalence of legal blindness and low vision were 12% and 45.12%, respectively. In the 1997 survey, the prevalence of blindness in same age group was 7.23% (95% CI 5.91-8.55). Between the two surveys, the prevalence of blindness due to corneal pathology declined from 1.9% to 1.1% but that of blindness due to unoperated cataract increased from 1.8% to 2.3%. CONCLUSIONS: The rate of disability has declined but the number of blind people has increased in Oman. The causes of blindness have changed from communicable/avoidable eye diseases to non-curable/chronic eye diseases, and the number with visual disabilities has increased. An increasing number of operations for cataract and improvements in the care for glaucoma and diabetic retinopathy are recommended.     

Assessment of Apoptosis Regulating Factors BCL-2 and Fas Antigens on Malignant and Normal Plasma Cells

Multiple myeloma (MM) is characterised by slow proliferation of malignant plasma cells and their accumulation within the bone marrow. The dysregulation of programmed cell death (apoptosis) is a very important mechanism in the pathogenesis of this tumour. It prompted us to investigate the apoptosis regulating factors such as the pro-apoptotic Fas antigen and the anti-apoptotic protein BCL-2 on bone marrow malignant plasma cells in untreated patients with newly diagnosed MM and to compare them with their normal counterparts—plasma cells isolated from bone marrow of healthy individuals. Twenty-nine MM patients and 16 healthy persons were studied. Bone marrow mononuclear cells were isolated, indicated by monoclonal antibodies and analysed using the flow cytometry method. There was no statistically significant difference in BCL-2 expression in plasma cells between patients and control groups. However the percentage of BCL-2 positive cells was significantly related to the clinical stage of the disease. We detected statistically significant lower percentage of Fas positive cells in the patient group than in control.

We concluded that in MM at diagnosis the expression of BCL-2 in bone marrow malignant plasma cells was comparable to normal plasma cells but expression of Fas antigen on these cells was lower. It suggests that down regulation of Fas and normal regulation of BCL-2 may be implicated for myeloma cell survival and their escape from apoptosis in vivo.