Induction, Recovery, and Safety Characteristics of Sevoflurane in Children Undergoing Ambulatory Surgery: A Comparison with Halothane

Background: Sevoflurane is an inhalational anesthetic with characteristics suited for use in children. To determine whether the induction, recovery, and safety characteristics of sevoflurane differ from those of halothane, the following open-labeled, multicenter, randomized, controlled, phase III study in children undergoing ambulatory surgery was designed.

Methods: Three hundred seventy-five children, ASA physical status 1 or 2, were randomly assigned in a 2:1 ratio to receive either sevoflurane or halothane, both in 60% N2 O and 40% O2. Anesthesia was induced using a mask with an Ayre's t piece or Bain circuit in four of the centers and a mask with a circle circuit in the fifth center. Maximum inspired concentrations during induction of anesthesia were 7% sevoflurane and 4.3% halothane. Anesthesia was maintained by spontaneous ventilation, without tracheal intubation. End-tidal concentrations of both inhalational anesthetics were adjusted to 1.0 MAC for at least 10 min before the end of surgery. Induction and recovery characteristics and all side effects were recorded. The plasma concentration of inorganic fluoride was measured at induction of and 1 h after anesthesia.

Results: During induction of anesthesia, the time to loss of the eyelash reflex with sevoflurane was 0.3 min faster than with halothane (P < 0.001). The incidence of airway reflex responses was similar, albeit infrequent with both anesthetics. The total MAC *symbol* h exposure to sevoflurane was 11% less than the exposure to halothane (P < 0.013), although the end-tidal MAC multiple during the final 10 min of anesthesia was similar for both groups. Early recovery as evidenced by the time to response to commands after sevoflurane was 33% more rapid than it was after halothane (P < 0.001), although the time to discharge from hospital was similar for both anesthetics. The mean (+/-SD) plasma concentration of inorganic fluoride 1 h after discontinuation of sevoflurane was 10.3+/-3.5 micro Meter. The overall incidence of adverse events attributable to sevoflurane was similar to that of halothane, although the incidence of agitation attributable to sevoflurane was almost threefold greater than that attributable to halothane (P < 0.004).     

Evolution of a form of pure alexia without agraphia in a child sustaining occipital lobe infarction at 21/2 years

The progress of cognitive visual dysfunction over an 8-year period of a child who sustained bilateral occipital-lobe infarctions at the age of 21/2 years is described. She survived with normal intelligence and went on to attend mainstream school. She manifested many features of cognitive visual impairment and, in particular, developed a form of pure alexia without agraphia. She achieved some letter-by-letter reading but no sight vocabulary development, including to her own name. She learned to write imaginatively employing phonetically true spelling but cannot read what she has written. Her progress and the difficulties encountered during the management of her condition are discussed in this first case report of the evolution of pure alexia without agraphia in childhood. The features of this syndrome in the developing child who has never developed the capacity to read are contrasted with that seen in affected adults.     

Severe rhinosinusitis

Rhinosinusitis is diagnosed frequently in clinical practice, but the term may in fact encompass a wide spectrum of diseases. Inflammation of the nasal and sinus mucosa can arise from various causes and lead to different sequelae. Moreover, the term rhinosinusitis is more accurate than sinusitis. Causes range from a viral infection leading to the common cold to an invasive, fungal infection. An accurate diagnosis is important because effective therapy is available if recognized early and if specific therapy is used. Importantly, there is a close relationship between upper and lower airway disease and each have unique structural and functional differences that make an understanding of rhinosinusitis important not only for upper airway disease, but also for the management of asthma. All too often, rhinosinusitis becomes chronic and this becomes a challenge because medical therapy may not be sufficient to control disease. Finally, we should note that the differential diagnosis of rhinosinusitis is extensive and physicians should place heavy emphasis not only on the history, but also on appropriate imaging studies. A normal exam does not rule out the possibility or rhinosinusitis. Finally, we should emphasize that effective treatment is dependent on the etiology of the symptoms but also dependent on whether it is acute or chronic.     

Of sleep state and postnatal age on arousal responses induced by mild hypoxia in infants

STUDY OBJECTIVES: It has been suggested that mild hypoxia may not be a potent stimulus for arousal during sleep in infants because infants frequently fail to arouse from quiet sleep (QS). Our aim was to characterize arousal responses of sleeping infants in both active sleep (AS) and QS under normoxic and mildly hypoxic (15% O2) conditions over the first 6 months of life. PARTICIPANTS: Five healthy term and 6 healthy preterm infants were each studied at 2 to 5 weeks, 2 to 3 months, and 5 to 6 months postterm. All infants underwent daytime polysomnography during which nasal airflow was monitored using a purpose-built pneumotachograph. All infants were studied under both normoxic (21% O2) and hypoxic (15% O2, balance N2) conditions (presentation order randomized) in each sleep state at each study age. Tests were terminated at arousal, O2 saturation falling below 85%, or 5 minutes (failure to arouse). MEASUREMENTS: Probability of failure to arouse and mean arousal latency were compared between each experimental condition, with each infant serving as its own control. RESULTS: Infants aroused more frequently under hypoxic conditions than under normoxic conditions. Overall, arousal latencies were shorter during hypoxia compared to normoxia in both sleep states at each age. Arousal latencies were longer in QS compared to AS in both hypoxic and normoxic conditions. CONCLUSION: In sleeping infants, mild hypoxia serves as a stimulus for arousal in both AS and QS. Of particular significance is our finding that arousal from AS is readily elicited by mild hypoxia.     

Effect of mebendazole againstEchinococcus granulosus andTaenia hydatigena cysts in naturally infected sheep and relevance to larval tapeworm infections in man

The ability of three treatment schedules of mebendazole to kill well-established hydatid cysts was studied. Pregnant sheep, naturally infected withEchinococcus granulosus and/orTaenia hydatigena, were treated daily with mebendazole at a dose rate of 50 mg/kg body weight for either five days, one month, or three months.At autopsy, seven months after the commencement of treatment, no evidence was found that the 5-day treatment schedule had any damaging effect onE. granulosus cysts. The effects of the one month treatment were equivocal. There was evidence of a damaging effect from the 3-month treatment schedule and protoscoleces were not infective to dogs. NoT. hydatigena cysts survived the 1- and 3-month treatments, but organisms from the 5-day treatment were infective to dogs.These results forE. granulosus in sheep suggest that long-term treatment with mebendazole may be required in hydatid disease in man. The results obtained forT. hydatigena in sheep are discussed in relation to the treatment of cysticercosis fromT. solium in man. Mebendazole showed no untoward effect on the sheep or their lambs.     

Tg cells in peripheral blood lymphocytes from patients with rheumatoid arthritis

Using combinations of methods for detecting Fc receptors and B lymphocytes, non-B, non-T lymphocytes and T lymphocytes we have shown T_G cells to be significantly increased in rheumatoid arthritis (RA) patients' peripheral blood lymphocytes (PBL). The possible significance of this finding to the disease process is discussed.     

Infant feeding and overweight in two Oxfordshire towns

In a study of feeding and growth in the first year of life in two Oxfordshire market towns, the frequency of overweight babies was the same for the 'intervention' town (where a research health visitor gave intensive advice to mothers on feeding) as for the control town. Eighteen per cent of bottle-fed infants and three per cent of those breast fed were overweight at one year. It seems that an increase in the number of health visitors does not affect the frequency of overweight infants, but it may be that a greater emphasis on breast feeding might reduce the frequency.     

The effect of hydrolytic enzymes on the acetylcholine sensitivity of the skeletal muscle cell membrane

Isometric tension developed by rat soleus and extensor digitorum longus (EDL) muscles in response to acetylcholine (Ach) applied in vitro was recorded. Tension of contractures elicited in response to Ach increased after muscles had been incubated with phospholipase C, pepsin, or soluble fractions prepared from muscle homogenate.Using intracellular microelectrodes, resting membrane potential (RMP) and depolarisation in response to Ach added to the bathing medium were recorded in endplate-free regions of the muscle fibres. No significant change in RMP was observed in muscles incubated with soluble muscle fraction or phospholipase C, but depolarisation in response to Ach or carbachol was significantly increased. The time course for the increase in depolarisation and the contracture response to Ach was similar.When all available receptors were blocked with -bungarotoxin prior to incubation so that no response to Ach could be elicited, with subsequent incubation in muscle soluble fraction or phospholipase C, both contractures and depolarisation in response to Ach returned. These results support the hypothesis that receptors, not previously available to interact with Ach or -bungarotoxin were revealed following incubation.     

p21 ras protein expression in benign and malignant

The ras oncogenes encode for GTP binding and GTPase active proteins of relative molecular mass 21 000 (p21^ras) which are involved in the transduction of stimuli for cell proliferation. There have been conflicting reports about the detection and significance of expression of p21^ras protein in human breast disease as determined by immunohistochemistry. The antibody Y13-259, which detects a single protein of M_r 21 000, has been applied immunohistochemically to frozen sections of normal, benign proliferative breast, fibroadenomas, and carcinomas. Uniform staining of normal breast epithelium and myoepithelium was found, with occasional stronger staining in areas of epithelial hyperplasia in benign breast disease. Contrary to previous reports, decreased expression, usually heterogeneous, was found in half of the carcinomas examined. Thirty per cent of the carcinomas exhibited heterogeneous staining stronger than that of normal breast, interpreted as increased expression of p21^ras protein. This did not relate to tumour grade or node status but showed a significant correlation with proliferation rate as determined by the monoclonal antibody Ki-67. This study confirms previous reports that p21^ras protein expression is a feature of normal cells, and has identified increased expression in 30 per cent of tumours associated with higher proliferation rates, which is a lower incidence than previously claimed when a different antibody was employed.     

Detection of Candida in concentrated oral rinse cultures by real-time PCR

The incidence of oral candidosis has increased in recent years, largely as a result of the emergence of human immunodeficiency virus infection and the more widespread use of immunosuppressive chemotherapy. This development has been associated with a need for more reliable methods for the detection of Candida. The present study assessed the performance of a real-time PCR and two block-based PCRs for the detection of Candida in 193 concentrated oral rinse culture (CRC) specimens. A total of 102 CRC specimens were positive by culture for Candida; and 96, 90, and 75 of these were also positive by real-time, N18-specific, and internal transcribed spacer (ITS)-specific PCRs, respectively. The five false-negative results by the real-time PCR were all non-Candida albicans positive by culture. Of the 91 culture-negative CRC specimens, 20, 41, and 44 were positive by the real-time PCR and the N18- and ITS-specific PCRs, respectively. All three PCRs detected fungal DNA in 8 culture-negative CRC specimens, with a further 30 being positive by two of the three PCRs. A total of 32 CRC specimens were Candida free by all methods. In summary, a real-time PCR that provides a sensitive, specific, and rapid alternative technique for detection of Candida in the mouth is described.