Comparison of the effects of xamoterol, atenolol and propranolol on breathlessness, fatigue and plasma electrolytes during exercise in healthy volunteers

Sorensen, EV; Jensen, H.; Færgeman, Ole

doi:10.1007/bf00280106

Cited by 3 publications

(1 citation statement)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Calcium was una ected in the studies of adrenergic agents by Sorensen. 20 The mean sodium concentrations in each group were the same, but ®ve in the control group and eight in the ventilated group had values lower than 132 mmol/l, the lowest in the control group being 126 and in the ventilated group 128. The low sodium values did not appear to be related to any other biochemical ®ndings.…”

Section: Acid-base and Electrolytesmentioning

confidence: 85%

Respiratory alkalosis and associated electrolytes in long-term ventilator dependent persons with tetraplegia

Watt¹,

Silva

2001

Spinal Cord

View full text Add to dashboard Cite

Study design: A pilot case control study of the acid-base and electrolyte status in 30 longterm ventilator-dependent (LTVD) and 30 self ventilating persons with tetraplegia. Objectives: To assess the extent of respiratory alkalosis and screen for associated hypokalaemia, hypomagnesaemia and/or hypophosphataemia. Setting: Medically stable persons with tetraplegia under the long-term care of the Southport Spinal Injuries Centre, England. Methods: Blood gases and electrolytes were sampled from 30 control patients with tetraplegia and from 30 patients having been LTVD for more than 12 months. Results: All the blood gas measurements in the LTVD group lay outside both the reference range and the 95% con®dence intervals (CI) of the control group: pH 7.46 (0.06); PCO 2 3.46 (1.1) kPa; bicarbonate 18.3 (3.8) and base excess 73.2 (2.8) mmol/l; PO 2 13.8 (2.8) kPa (means and standard deviations). The serum potassium, magnesium, phosphate, and sodium means lay within the reference ranges but the potassium, phosphate and calcium were at or below the 95% CI of the control values. One patient on part-time ventilatory support having less bicarbonate compensation had low serum electrolytes during ventilation. Conclusion: There was no evidence of biochemical jeopardy from long-term mechanical hyperventilation although acutely administered hyperventilation has the potential to cause falls in serum potassium, magnesium and phosphate and so caution should be exercised in part-time ventilated persons. The full range of electrolytes should be assayed during stabilisation in LTVD and periodically thereafter. Hyperventilation helps to maintain good oxygenation in LTVD persons with paralysis and normal lungs. Sponsorship: None.

show abstract

Section: Acid-base and Electrolytesmentioning

confidence: 85%

Respiratory alkalosis and associated electrolytes in long-term ventilator dependent persons with tetraplegia

Watt¹,

Silva

2001

Spinal Cord

View full text Add to dashboard Cite

show abstract

Dynamics and Consequences of Potassium Shifts in Skeletal Muscle and Heart During Exercise

Sejersted

Sjøgaard

2000

Physiological Reviews

418

433

View full text Add to dashboard Cite

Since it became clear that K(+) shifts with exercise are extensive and can cause more than a doubling of the extracellular [K(+)] ([K(+)](s)) as reviewed here, it has been suggested that these shifts may cause fatigue through the effect on muscle excitability and action potentials (AP). The cause of the K(+) shifts is a transient or long-lasting mismatch between outward repolarizing K(+) currents and K(+) influx carried by the Na(+)-K(+) pump. Several factors modify the effect of raised [K(+)](s) during exercise on membrane potential (E(m)) and force production. 1) Membrane conductance to K(+) is variable and controlled by various K(+) channels. Low relative K(+) conductance will reduce the contribution of [K(+)](s) to the E(m). In addition, high Cl(-) conductance may stabilize the E(m) during brief periods of large K(+) shifts. 2) The Na(+)-K(+) pump contributes with a hyperpolarizing current. 3) Cell swelling accompanies muscle contractions especially in fast-twitch muscle, although little in the heart. This will contribute considerably to the lowering of intracellular [K(+)] ([K(+)](c)) and will attenuate the exercise-induced rise of intracellular [Na(+)] ([Na(+)](c)). 4) The rise of [Na(+)](c) is sufficient to activate the Na(+)-K(+) pump to completely compensate increased K(+) release in the heart, yet not in skeletal muscle. In skeletal muscle there is strong evidence for control of pump activity not only through hormones, but through a hitherto unidentified mechanism. 5) Ionic shifts within the skeletal muscle t tubules and in the heart in extracellular clefts may markedly affect excitation-contraction coupling. 6) Age and state of training together with nutritional state modify muscle K(+) content and the abundance of Na(+)-K(+) pumps. We conclude that despite modifying factors coming into play during muscle activity, the K(+) shifts with high-intensity exercise may contribute substantially to fatigue in skeletal muscle, whereas in the heart, except during ischemia, the K(+) balance is controlled much more effectively.

show abstract

Hyperkalemia Complicating Propranolol Treatment of an Infantile Hemangioma

Pavlakovic

Kietz²,

Lauerer³

et al. 2010

Pediatrics

View full text Add to dashboard Cite

Propranolol treatment was recently reported to be successful for the management of severe infantile hemangioma. Known adverse effects of propranolol treatment include transient bradycardia, hypotension, hypoglycemia, and bronchospasm (in patients with underlying spastic respiratory illnesses), which led to a general recommendation to gradually increase propranolol dosage and closely monitor patients' hemodynamics at the onset of therapy. To date, no serious or unexpected adverse effects that required specific intervention have been reported. In this report, we describe the case of a 17-week-old female preterm infant who presented with a large, ulcerated, cutaneous-subcutaneous hemangioma of the right lateral thoracic wall, which we treated successfully with propranolol. A few days into therapy, a potentially life-threatening adverse effect, severe hyperkalemia, was observed and required treatment with loop diuretics, fluids, and nebulized salbutamol to normalize her serum potassium levels. This therapy could be gradually tapered and finally discontinued only after several weeks of propranolol treatment. Our case report indicates that, at least during the initial phase of the propranolol treatment of infantile hemangioma, close monitoring of serum electrolytes, besides the monitoring of hemodynamics and blood glucose, is necessary.

show abstract

Comparison of the effects of xamoterol, atenolol and propranolol on breathlessness, fatigue and plasma electrolytes during exercise in healthy volunteers

Cited by 3 publications

References 20 publications

Respiratory alkalosis and associated electrolytes in long-term ventilator dependent persons with tetraplegia

Respiratory alkalosis and associated electrolytes in long-term ventilator dependent persons with tetraplegia

Dynamics and Consequences of Potassium Shifts in Skeletal Muscle and Heart During Exercise

Hyperkalemia Complicating Propranolol Treatment of an Infantile Hemangioma

Contact Info

Product

Resources

About