Airway management training using the laryngeal mask airway: a comparison of two different training programmes.

Nurses without prior experience in the use of the laryngeal mask airway (LMA) were randomly allocated to one of two groups to be trained in the emergency technique of insertion of an LMA. Group A (32 nurses) were trained only on a manikin and group B (20 nurses) were trained on a manikin and with live anaesthetised patient practice in theatre (five successful insertions). Without further practice, both groups were asked to insert an LMA in a live patient in theatre 3 months after initial training. Three attempts per nurse were allowed. In group A, 75% passed the LMA successfully at the first attempt, 22% at the second attempt and 3% (one nurse) at the third attempt. In group B, 80% were successful at first attempt and 20% at the second attempt. Skill performance and retention were shown to be high following either training method, with no significant difference between the performance of either group (chi 2). We have shown that manikin-only training in the emergency technique for LMA insertion is as effective as live patient training. It is proposed that manikin training alone may be adopted as a future training modality if, as is expected, the use of the LMA in resuscitation becomes more commonplace.

Growth hormone responses to treadmill sprinting in sprint- and endurance-trained athletes.

The purpose of the present study was to examine the growth hormone (GH) response to treadmill sprinting in male (M) and female (F) sprint- and endurance-trained athletes. A group of 11 sprint-trained (ST; 6M, 5F) and 12 endurance-trained (ET; 6M, 6F) athletes performed a maximal 30-s sprint on a nonmotorized treadmill. Peak power and mean power expressed in watts or in watts per kilogram body mass were higher in ST than in ET (P < 0.01) and in the men compared to the women (P < 0.01). Serum GH was greater in ST than in ET athletes, but was not statistically significantly different between the men and the women [mean peak GH: ST 72.4 (SEM 12.5) compared to ET 26.3 (SEM 4.9) mU.1(-1), P < 0.01; men 59.8 (SEM 13.3) compared to the women 35.8 (SEM 7.4) mU.1(-1), n.s.]. Plasma ammonia and blood lactate concentrations were higher and blood pH lower during 1 h of recovery after the sprint in ST compared to ET (all P < 0.01). Multiple log linear regression showed that 82% of the variation in the serum peak GH response was explained by the peak power output and peak blood lactate response to the sprint. As serum GH was still approximately ten times the basal value in ST athletes after 1 h of recovery, it is suggested that the exercise-induced increase in GH could have important physiological effects in this group of athletes, including increased protein synthesis and sparing of protein degradation leading to maintained or increased muscle mass.

Dynamics of phenol degradation by Pseudomonas putida.

Pure cultures of Pseudomonas putida (ATCC 17484) were grown in continuous culture on phenol at dilution rates of 0.074-0.085 h(-1) and subjected to step increases in phenol feed concentration. Three distinct patterns of dynamic response were obtained depending on the size of the step change used: low level, moderate level, or high level. During low level responses no accumulations of phenol or non-phenol, non-glucose-dissolved organic carbon, DOC(NGP), were observed. Moderate level responses were characterized by the transient accumulation of DOC(NGP) with a significant delay prior to phenol leakage. High level responses demonstrated a rapid onset of phenol leakage and no apparent accumulations of DOC(NGP). The addition of phenol to a continuous culture of the same organism on glucose did not result in transient DOC(NGP) accumulations, although transient phenol levels exceeded 90 mg l(-1). These results were consistent with intermediate metabolite production during phenol step tests coupled with substrate-inhibited phenol uptake and suggested that traditional kinetic models based on the Haldane equation may be inadequate for describing the dynamics of phenol degrading systems.

Intrasplenic blood cell kinetics in man before and after brief maximal exercise.

1. After a 4 min period of maximal exercise in 10 normal subjects (14 studies), there was a consistent decrease in total blood volume and a consistent increase in erythrocyte indices, which were maximal immediately after exercise. Peripheral platelet and leucocyte counts increased, but did not reach maximal values until 5-10 min after the end of exercise. 2. The distributions of 99mTc-labelled erythrocytes (five studies), 111In-labelled platelets (five studies) and 111In-labelled granulocytes (four studies) were monitored with a gamma-camera immediately after injection and before and after maximal exercise performed 60 min after injection. 3. Labelled erythrocytes equilibrated rapidly between the spleen and circulating blood after injection, whereas labelled platelets and granulocytes equilibrated more slowly. After exercise, each cell type was released from the spleen with a time course that was the reciprocal of the time course of the corresponding cell count in peripheral blood. Thus, whereas the radioactivity of 99mTc-labelled erythrocytes in the spleen, which fell to 0.46 (SD 0.09) of the pre-exercise value, increased towards its baseline value as soon as exercise was completed, the radioactivities of 111In-labelled platelets and 111In-labelled granulocytes decreased, to respective minimum values of 0.61 (0.09) and 0.63 (0.09) of the pre-exercise levels, 5-10 min after the end of exercise. The exercise-induced changes in lung radioactivity for each cell type, and their time courses, broadly reflected those in the corresponding cell counts in peripheral blood. Liver radioactivity tended to decrease for each cell type.(ABSTRACT TRUNCATED AT 250 WORDS)

Granulocyte margination in the human lung and its response to strenuous exercise.

1. It is widely believed that the lung is an important site of granulocyte margination and releases most of the granulocytes of the peripheral neutrophilia of exercise. 2. We measured granulocyte margination in the lung in terms of the lung total blood granulocyte pool and the lung circulating granulocyte pool in eight patients without inflammatory disease or evidence of lung pathology by comparing the regional gamma-camera lung count rate of 111In-labelled granulocytes with that of 111In-labelled erythrocytes. According to the respective 111In activities in peripheral blood samples taken between 5 and 40 min after granulocyte injection, the lung marginating granulocyte pool was 0.78 (SEM 0.045) of the lung total blood granulocyte pool or 4.6 (0.92) of the lung circulating granulocyte pool 5 min after injection, decreasing to plateau values of 0.57 (0.053) and 1.53 (0.28) from 20 min after injection. This compared with corresponding whole-body ratios of about 0.6 and 1.5, respectively. 3. After 4 min of maximal exercise in four normal subjects given 111In-labelled granulocytes 60 min before exercise, the 111In-labelled granulocyte count rate over the lung increased to 1.23 (0.05) of the pre-exercise value with a time course that was essentially identical with the time course of the peripheral native neutrophilia. The spleen 111In signal decreased with the same time course, reaching a minimum of 0.63 (0.05) of the pre-exercise level at 5-10 min after the end of exercise.(ABSTRACT TRUNCATED AT 250 WORDS)

Delayed recovery of muscle pH after short duration, high intensity exercise in malignant hyperthermia susceptible subjects.

Six subjects susceptible to malignant hyperthermia (MHS) and seven control subjects exercised for 4 min at 120% of their calculated maximal oxygen uptake on a bicycle ergometer. Mean (SEM) muscle pH, measured with a needle-tipped electrode in the vastus lateralis muscle, decreased from a resting value of 7.16 (0.04) to 6.78 (0.04) after exercise in the control group, and from 7.15 (0.05) to 6.56 (0.05) in the MHS group (P less than 0.01 compared with control group). A further decrease in muscle pH to 6.68 (0.06) by 5 min after exercise occurred in the control group, followed by incomplete recovery to 7.06 (0.04) 30 min after exercise. In the MHS group, however, muscle pH decreased to 6.45 (0.05) 5 min after exercise before recovering slowly to only 6.64 (0.07) after 30 min (P less than 0.01 compared with control group). There was no difference in muscle temperature, venous pH or venous lactate concentrations between the two groups. The results show that there is abnormal recovery of muscle pH after short-duration, high-intensity exercise in MHS subjects.

Continuous intramuscular pH measurement during the recovery from brief, maximal exercise in man.

Muscle pH and temperature were measured before, and continuously for 30 min after, a 30-s maximal sprint exercise in ten subjects. These measurements were made with a needle-tipped pH electrode and a thermocouple placed in vastus lateralis. Venous blood samples were collected for pH, lactate and catecholamine estimations and measurements were also made of the arterial blood pressure and heart rate. The muscle and venous pH decreased from 7.17 +/- 0.01 (mean +/- SEM) and 7.39 +/- 0.01 to 6.57 +/- 0.04 and 7.04 +/- 0.03, respectively, in response to the exercise. No significant recovery occurred in either pH measurement for 10 min, after which muscle pH increased to 7.03 +/- 0.03 and venous pH to 7.29 +/- 0.01 by 30 min. Muscle temperature increased by 2.1 degrees C with exercise and also failed to return to pre-exercise values by 30 min. Blood lactate concentration increased from 0.75 +/- 0.04 mmol l-1 before exercise to a peak value of 15.76 +/- 0.35 mmol l-1 5 min after completion of the exercise, and then declined slowly to 10.30 +/- 0.61 mmol l-1 by 30 min. Arterial blood pressure increased transiently with exercise but recovered rapidly, whereas the exercise-induced tachycardia was sustained throughout the recovery period. The recovery from the metabolic and cardiovascular responses to maximal sprint exercise in man is incomplete 30 min after cessation of the exercise.

Ventilatory effects of a propofol infusion using a method to rapidly achieve steady-state equilibrium.

The ventilatory effects of a propofol infusion were studied in 10 females premedicated with atropine and nine with papaveretum and atropine. The infusion, at a rate of 20 mg kg-1 h-1 for 5 min, reducing to 12 mg kg-1 h-1 for 10 min and then 6 mg kg-1 h-1 thereafter, was known to produce a steady-state plasma propofol concentration for 20-25 min after 25 min from commencement. Minute ventilation, tidal volume, frequency and response to breathing carbon dioxide were measured before the infusion and during the steady-state period. Propofol decreased minute ventilation to 56% and 46% (P less than 0.01) of their mean control values in the atropine and papaveretum groups, respectively. Mean tidal volume was decreased to 41-44% (P less than 0.02) by propofol, but a tachypnoea observed in the atropine group during the infusion was absent in the papaveretum group. Propofol alone had no effect on the slopes of the carbon dioxide response curves but did produce a shift to the right (P less than 0.05). Following papaveretum premedication the minute ventilation-carbon dioxide response curve slope, was decreased to 55% of its mean control volume value by the infusion, but this failed to reach statistical significance.

The neuroleptic malignant syndrome. Case report with a review of the literature.

Following the administration of fluphenthixol (a depot phenothiazine) for a psychotic illness, a 44-year-old woman developed weakness, rhabdomyolysis and renal failure, together with hyperthermia (42 degrees C) and signs of both autonomic and central nervous system dysfunction. She died following massive intestinal haemorrhage, intra-abdominal sepsis and probable disseminated intravascular coagulation. A diagnosis of neuroleptic malignant syndrome had been made, but treatment with dantrolene sodium was probably instituted too late to prevent the progress of the complications she had developed. This syndrome, which follows the use of phenothiazines or butyrophenones, is rare, potentially fatal and probably underdiagnosed. It has been likened to malignant hyperthermia, but a review of the literature points to many differences. Both dantrolene sodium and dopaminergic drugs (bromocriptine, amantidine and L-dopa) have been shown to be efficacious and their continued use, despite a failure in this case, is advocated until more is known about this syndrome.