[The laryngeal mask in pediatric anesthesia]. / La maschera laringea in anestesia pediatrica.

We carried out a perspective study in order to assess the ease of insertion, the type and the incidence of perioperative complications connected with the use of the Laryngeal Mask Airway (LMA). We examined 300 consecutive patients, M/F 261/39, average age 4.2 yrs. (range 0.1-16), ASA I-II, who underwent surgical operations of short or average length not involving the pleural, the oropharyngeal or the peritoneum cavity. The choice about anesthesia was left to the discretion of the anesthesiologist. In 27 cases the position of the LM was controlled through a flexible fiberoptics. In 269 patients (89.6%) the LMA was correctly positioned during the first attempt. In 27 patients (9%), 2 or more attempts were necessary, and in 4 patients (1.4%) it was not possible to set the LMA. No differences of statistical significance were noticed between the different size of LMA, with regards to the facility of insertion. The control through fiberoptics showed a correct position, from an anatomical point of view, in 11 patients (41%), whereas in 13 patients (48%) some signs of partial obstruction were noticed (epiglottis interposing between the opening of LMA and larynx) and in 3 patients (11%) vocal cords are not visible. The following complications took place: laryngeal spasm on induction (2.3%), cough or movements on positioning (2.3%), hypoxia (4.3%), obstruction (1%), laryngeal spasm on awakening (1.7%), trauma (5%) and vomiting (0.3%). No connections were found between the size of LMA and total complications. Nevertheless, cough or movement during positioning and laryngeal spasm on awakening were significantly more frequent with LMA n. 3. In our experience, the LMA proved to be effectual and safe in the control of the airway during elective operations in pediatric surgery.

[The use of low doses of intermediate acting muscle relaxants in adenotonsillectomy]. / Uso dei miorilassanti a media durata d'azione a dosaggi ridotti in interventi di adenotonsillectomia.

In this study we compared the efficacy of a reduced dose of medium term neuromuscular blocking agents atracurium (0.20 mg/kg) and vecuronium (0.04 mg/kg) in short-term (8-10 min) pediatric surgery. Eighty-four children (ASA I and II) undergoing adenotonsillectomy were selected for this study. Their average age was 56 months (range 30-121 months). We compared intubation conditions and the level of neuromuscular blockade using accelerometry. The induction and maintenance of anesthesia were achieved by anaesthetic gas (halothane first followed by isoflurane). Later on 57 children received vecuronium 0.04 mg/kg (group V) and 27 atracurium 0.20 mg/kg (group A). The latency period was similar in both groups (114.5 +/- 36.1 sec gruppo V vs 100.1 +/- 32.1 sec gruppo A). Intubation was performed in the same period of time (159 +/- 17.4 sec gruppo V vs 156 +/- 20.8 sec gruppo A) and the stimulus was always less than 5% of the baseline values. Intubation was considered excellent in 93% of patients of group V, good in 3.5% and poor in 3.5%. Conversely in patients of group A intubation was considered excellent in 85%, good in 11.5% and poor in 3.5% (n.s.). The neuromuscular recovery, measured by T1 > 5%, was faster in group V (493.6 +/- 154.3 sec gruppo V) than group A (652.6 +/- 210.9 sec gruppo A) (p < 0.001). The TOF ratio during extubation was significantly lower in group A (0.556 +/- 0.177 gruppo A) than in patients of group V (0.789 +/- 0.173 gruppo V) (p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Insulin resistance after surgery: normalization by insulin treatment.

1. Injury is known to be associated with variable degrees of tissue insensitivity to insulin. We measured insulin resistance in a group of non-obese, glucose-tolerant patients undergoing major elective surgery with an uncomplicated post-operative course. 2. Shortly after surgery, hyperglycaemia (7.3 +/- 0.6 versus 4.2 +/- 0.3 mmol/l glucose pre-surgery, mean +/- SEM, P less than 0.01) with normal insulin concentrations (73 +/- 15 versus 64 +/- 18 pmol/l) suggested the presence of insulin resistance. Counter-regulatory hormones were raised, whole-body protein oxidation was doubled (P less than 0.01) and energy expenditure was up by 18% (P less than 0.01). 3. Insulin sensitivity was quantified by clamping plasma glucose concentrations at 5.6 mmol/l during 24 h of total parenteral nutrition (15% protein, 55% glucose and 30% fat, supplying 1.25 times the measured resting energy expenditure) with a variable infusion of exogenous insulin. After surgery, eight times more insulin was needed than before surgery (14.14 +/- 1.15 versus 1.78 +/- 0.29 pmol min-1 kg-1, P less than 0.001) to maintain euglycemia. 4. After surgery, stimulation of net carbohydrate oxidation (18.8 +/- 1.4 versus 17.2 +/- 1.8 mumol min-1 kg-1 preoperatively, not significant), suppression of lipolysis and lipid oxidation and inhibition of ketogenesis occurred to the same extent as before surgery. Of the infused nutrients, the glucose was all oxidized, amino acids replaced endogenous protein losses (= neutral nitrogen balance) and lipids were stored. Insulin administration caused no further increment in oxygen consumption or energy expenditure.(ABSTRACT TRUNCATED AT 250 WORDS)

Inadvertent catheterization of the internal thoracic vein mimicking pulmonary embolism: a case report.

Although aberrant locations are typical complications of central venous catheterization, the right internal thoracic vein (mammary vein) is an exceptional one. A case of this unusual aberrant location occurring after right internal jugular venous cannulation for total parenteral nutrition, is described. This aberrant position caused signs and symptoms resembling pulmonary embolism. This is the first known description of the symptoms induced by the infusion of parenteral solution into the right internal thoracic vein.

Energy metabolism of surgical patients in the early postoperative period: a reappraisal.

Energy metabolism was measured at the bedside in 22 uncomplicated surgical patients in the early (24 to 48 h) postoperative period with the use of continuous computerized indirect calorimetry with a canopy system. Energy production rates were higher than those predicted by the Harris-Benedict formula both in absolute value (1516 +/- 61 vs. 1387 +/- 49 kcal/day, p less than .05) and when normalized by body weight (BW; 23.5 +/- 0.5 vs. 21.7 +/- 0.5 kcal/day.kg BW, p less than .01) or by lean body mass (LBM; 32.8 +/- 0.8 vs. 30.2 +/- 0.9 kcal/day.kg LBM, p less than .01). Furthermore, surgical patients had higher energy production rates than those measured in 22 overnight fasted, resting healthy subjects matched for age, sex, and body size (23.5 +/- 0.5 vs. 21.8 +/- 0.6 kcal/day.kg BW, p less than .05). In both the patients and the control group, measured energy production bore a direct relation to LBM. We conclude that the early postoperative period of uncomplicated surgery is associated with a small (about 7%) but consistent increase in energy metabolism above the level observed in the overnight fasted, resting healthy individual. This increase appears to be an effect of surgery itself, and is not predicted by Harris-Benedict equations.