Sixty boys, aged 1-10 yr, undergoing orchidopexy were allocated randomly to receive one of three solutions for caudal extradural injection. Group A received 0.25% bupivacaine 1 ml kg-1 with adrenaline 5 micrograms ml-1 (1/200,000), group C received 0.25% bupivacaine 1 ml kg-1 with clonidine 2 micrograms kg-1 and group K received 0.25% bupivacaine 1 ml kg-1 with ketamine 0.5 mg kg-1. Postoperative pain was assessed using a modified objective pain score and analgesia was administered if this score exceeded 4. The median duration of caudal analgesia was 12.5 h in group K compared with 5.8 h in group C (P < 0.05) and 3.2 h in group A (P < 0.01). There were no differences between the groups in the incidence of motor block, urinary retention or postoperative sedation.

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Abstract:The breath alcohol concentration (BrAC), standardized to the alveolar water vapour concentration has been shown to closely predict the arterial blood alcohol (ethanol) concentration (ABAC). However, a transient increase in the ABAC/BrAC ratio has been noticed, when alcohol is absorbed from the gastrointestinal tract (absorption phase) and the ABAC rapidly rise. We analysed the plot of simultaneously recorded alcohol, water vapour, and CO 2 against exhaled volume (volumetric expirogram) for respiratory deadspace volume (VD) , cumulative gas output and phase III slope within one breath to evaluate whether changes in the BrAC profile could explain this variability. Eight healthy subjects performed exhalations through pre-heated non-restrictive mouth pieces and the concentrations were measured by infrared absorption.In the absorption phase the respiratory VD of alcohol was transiently increased and the exhaled alcohol was displaced to the latter part of the expirogram. In the post-absorption phase, the respiratory VD for alcohol and water vapour was stable and always less than the respiratory VD for CO 2 , indicating that the first part of the exhaled alcohol and water originated from the conducting airway. The position of the BrAC profile between water vapour and CO 2 in the post-absorptive phase indicates an interaction within the conducting airway, probably including a deposition of alcohol onto the mucosa during exhalation. We conclude that the increase in the ABAC/BrAC ratio during the absorption phase of alcohol coincides with a transient increase in respiratory VD of alcohol and a delay in the appearance of alcohol in the exhaled air as the exhalation proceeds compared with the post absorption phase.

Estimation of kidney function is often part of daily clinical practice, mostly done by using the endoge-nous glomerular filtration rate (GFR)-markers creatinine or cystatin C. A recommendation to use both markers in parallel in 2010 has resulted in new knowledge concerning the pathophysiology of kidney disorders by the identification of a new set of kidney disorders, selective glomerular hypofiltration syndromes. These syndromes, connected to strong increases in mortality and morbidity, # Linnea Malmgren and Carl Öberg contributed equally as first authors.

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SummaryClinical and jibreoptic assessment of the positioning of the laryngeal mask airway was performed in 100 children. Clinical observation indicated a patent airway in 98% and severe airway obstruction in 2% of cases. Perfect positioning, as judged by jibreoptic laryngoscopy, was found in 49% and the epiglottis was within the mask in 49%. Fibreoptic evidence of partial airway obstruction in 17% was not detected clinically. Key wordsAnaesthesia; paediatric. Equipment; laryngeal mask airway, fibreoptic laryngoscope.The laryngeal mask airway (LMA) was designed following studies on the cadaveric adult larynx,' Three out of the four sizes of laryngeal mask currently available are appropriate for use in infants and children; size 1 in infants up to 6.5 kg, size 2 for infants and children from 6.5 to 25 kg and size 3 for larger children or small adults. Sizes 1 and 2 are scaled-down versions of adult masks. However, the relative anatomy of the larynx of infants and young children is known to differ from that of the adult; a higher and more anteriorly placed glottis with a relatively large floppy epiglottis may make correct placement of the LMA more difficult. We assessed the position of three sizes of LMA in anaesthetised children using a fibreoptic laryngoscope. MethodObservations were made on 100 consecutive healthy children (inpatients and outpatients) presenting for elective general surgery. Patients who were not fasted or those requiring tracheal intubation or intermittent positive pressure ventilation as part of the anaesthetic technique were not studied. Masks were inserted by the authors; two had previous experience with the technique in children and one had experience in adults. Clinical assessment of airway patency and fibreoptic laryngoscopy were performed by two observers.Premedication and the method of induction of anaesthesia (inhalational with halothane in nitrous oxide and oxygen or intravenous with propofol 3 mg/kg) were at the discretion of the anaesthetist. Masks were all inserted when the children were anaesthetised and breathing 4% halothane in nitrous oxide and oxygen (2: I). A Bain anaesthetic system was used in children over 15 kg and an Ayre's T-piece in smaller children.The LMA was inserted in a standard fashion according to the maker's recommendations (Intavent Laryngeal Mask Airway, DJ. Colgate Ltd., UK) and the cuff inflated with air. Correct positioning of the LMA was clinically determined as follows; resistance to continued advancement of the LMA with forward bulging of the larynx during insertion and outward movement of the LMA with cuff inflation. Airway patency was confirmed by observing synchronous respiratory movements of the chest and anaesthetic reservoir bag, by a lack of indrawing of intercostal and supraclavicular spaces and by confirming, on auscultation, air entry in both axillae when gently inflating the lungs.The actual position of the LMA was then ascertained by fibreoptic laryngoscopy (Olympus ENF P2) while an assistant prevented the mask from moving. Laryngoscopic find...

Background Left ventricular free wall rupture is an uncommon but catastrophic event following myocardial infarction, and considered the second leading cause of death in acute myocardial infarct. Different types of rupture exist from acute to sub acute types, but prognosis is usually poor. Early recognition and aggressive treatment is recommended.Case report We present a case of a 75-year-old man who was referred to our echo-lab for an out patient evaluation because of 1-week duration of worsening of chest pain. Standard transthoracic echocardiography showed hypokinesia in the apical portion of the anterior wall and basal portion of the inferior wall. The patient complained of shortness of breath immediately after the conclusion of the exam, and soon afterward became unconscious. Renewed echocardiography approximately 1 min after syncope displayed a newly developed echo-lucent rim around the heart consistent with left ventricular free wall rupture. Resuscitation was performed followed by attempts to evacuate the blood by needle aspiration, which failed. Open pericardiocentesis stabilised the patient until surgery could be performed. The patient survived and could be discharged 2 weeks later. Conclusion This case highlights the fact that rapid and accurate diagnosis is essential if patients with left ventricular free wall rupture are to survive.

Purpose. To test the hypothesis that a low-dose rocuronium acts mainly by means of reducing muscular endurance rather than by reducing momentary force. Methods. In a randomized placebo-controlled double-blinded study, eight healthy volunteers were studied in two sets of experiments. In the first set, the subjects made a sustained maximum effort with the dominant hand for 80 seconds while squeezing an electronic handgrip dynamometer at three minutes after intravenous administration of placebo, 0.04 or 0.08 mg/kg rocuronium. Handgrip force at initiation of testing (maximum handgrip force) and after 60 seconds was evaluated. In the second set, the ulnar nerve of the subjects was electrically stimulated every tenth second for at least 10 and a maximum of 30 minutes following the administration of placebo and 0.08 mg/kg rocuronium. Single twitch height of the adductor pollicis muscle was recorded. Results. There was no significant difference in the effect on maximum handgrip force at time 0 between the three different doses of rocuronium. As compared with placebo, handgrip force after 0.08 mg/kg rocuronium was reduced to approximately a third at 60 seconds (214 N (120–278) vs. 69 (30–166); p=0.008), whereas only a slight reduction was seen after 0.04 mg/kg (187 (124–256); p=0.016). Based on these results, the sustained handgrip force after 0.2 mg/kg at 60 seconds was calculated to be 1.27% (95% CI [0.40, 4.03]) of the maximum force of placebo. No effect on single twitch height after 0.08 mg/kg rocuronium at four minutes after drug administration could be detected. Conclusions. Subparalyzing doses of rocuronium show a distinct effect on muscular endurance as opposed to momentary force. The findings support the hypothesis that low doses of rocuronium act mainly by reducing muscular endurance, thereby facilitating, for example, tracheal intubation.