GUANETHIDINE IN HYPERTHYROIDISM

A Comparative Study of Full-Thickness Blepharotomy Versus Transconjunctival Eyelid Lengthening in the Correction of Upper Eyelid Retraction in Graves' Orbitopathy

BACKGROUND

The study was designed to compare the outcome of full-thickness blepharotomy and transconjunctival eyelid lengthening in the correction of upper eyelid retraction (UER) in patients with Graves' orbitopathy (GO).

METHODS

This is a prospective randomized interventional study. Following ophthalmic examination, determination of the ocular surface disease index (OSDI) and photography, 27 patients with UER were randomly assigned to either graded full-thickness blepharotomy (G1) or transconjunctival Müller muscle recession and graded disinsertion of the levator palpebrae superioris muscle (G2). Six months later, patients were reevaluated. Digital images were analyzed with the assistance of customized software. A standardized "normal range" of upper eyelid height and contour was calculated based on healthy controls. The outcome of the two groups was compared.

RESULTS

Forty-seven eyelids of 27 patients (19 female) with UER were included. Twenty-seven eyelids (15 patients) were allocated to G1 and 20 eyelids (12 patients) to G2. On average, surgery lasted 37.46 ± 5.73 min in G1 and 32.70 ± 8.39 min in G2. Based on the margin reflex distance, 93% of the eyelids in G1 and 85% in G2 were within the normal range after surgery. The corresponding figures for lid contour were 63 and 55%. Both groups displayed significant improvement in OSDI scores. No significant difference was observed in the overall comparison.

CONCLUSIONS

The two surgical techniques were equally effective in the treatment of UER from GO. Postoperative contour outcomes were considerably worse in patients with severe UER than in patients with mild or moderate UER, regardless of group.

LEVEL OF EVIDENCE II

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to Table of Contents or the online Instructions to Authors www.springer.com/00266 . Study registered on ClinicalTrial.gov number: NCT01999790.

The Pharmacotherapy of Thyroid Storm

A review of thyrotoxic storm is presented. Included are causes, symptomatology, and mortality rates. Special emphasis is placed on the strong correlation between adrenergic blockade and success rates in treating thyrotoxic storm. Pharmacotherapy of the acute storm patient is discussed in detail with respect to agents that (1) decrease production of thyroid hormones; (2) block release of preformed thyroid hormones from the gland; (3) blunt the effects of excess thyroid hormones on the various target organs (e.g., CNS and heart); and (4) serve to decrease the metabolic strain on all organ systems caused by thyrotoxic storm.

Beta-adrenoceptor blockade and anaesthesia for thyroidectomy

The administration of beta-adrenoceptor blocking drugs in the pre-operative preparation and operative management of thyrotoxic patients undergoing subtotal thyroidectomy is reviewed. Particular reference is made to some of the recent advances and it is emphasised that there has been a considerable reduction in the incidence of problems following judicious use of these drugs. The choice of anaesthetic technique employed for thyroidectomy is less important than the degree of control of thyrotoxicosis by the beta-adrenoceptor blocking drug. Propranolol has proved safe and effective for the majority of patients. The longer acting agent nadolol is easier to administer, particularly in the peri-operative period. Patients are rendered less thyrotoxic and safety thereby enhanced by adding potassium iodide for 10 days preoperatively. The combination of nadolol and potassium iodide offers real advantages in the preparation of the thyrotoxic patient for surgery.

The aponeurotic approach to eyelid retraction

A technique for the upper lid retraction that involves an anterior approach similar to aponeurotic ptosis surgery is presented. Instead of advancing the aponeurosis, it is recessed and Müller's muscle is completely extirpated. The lateral horn of the levator must be cut to relieve the marked temporal elevation of the eyelid. Lid height and contour are adjusted intraoperatively with patient cooperation. In the lower lid, the retractors are recessed via a conjunctival approach unless simultaneously performed with orbital decompression. Any amount of lid retraction may be corrected by this technique in the upper lid and up to 3 mm of lower lid retraction can be corrected. Lid height in both the upper and lower lid is lasting and predictable. Thirty-one patients (63 eyelids) have been operated on using this technique with good results. Results in 17 patients (35 eyelids) with follow-up ranging from 8 to 42 months are presented.

Haemodynamic effects of beta-adrenergic blockade in hyperthyroid patients with and without heart failure

Haemodynamic studies were performed in 10 patients with uncomplicated thyrotoxicosis and seven with thyrotoxic cardiac failure. The cardiac output of those with uncomplicated hyperthyroidism was higher than normal at rest. After 2 mg of intravenous propranolol there was a 13% fall but the level was still higher than normal. In patients with thyrotoxic cardiac failure the resting cardiac output was normal, but it fell after propranolol by 30% to subnormal levels. In both groups there was an increase in right heart pressures and fall in the rate of increase in arterial pressure, which indicated a decrease in myocardial contractility. These results indicate that increased autonomic activity is a compensatory phenomenon in hyperthyroid heart failure and that its abolition by beta-blocking drugs has a deleterious effect on cardiac function. They are therefore contraindicated in patients with thyrotoxic heart failure.

Whither thyrotoxicosis?

For 30 years the thyrotoxic patient has been subjected to a plurality of treatments by surgery, radio-iodine and long term anti-thyroid drugs. These therapies have been accepted as complementary to the needs of the individual patient, without regard for long term results or the economic situation as it affects both patient and hospital services. In the context of surgical treatment which is now available, it is suggested that the advantages of operation over other therapies presage a reversion to surgery as the treatment of choice.

Atrial fibrillation and hyperthyroidism: a new look at their relationship and therapy with lidoflazine

Various kinds of dysrhythmias are found in association with hyperthyroidism but especially atrial fibrillation. The causal relationship of chronic atrial fibrillation and the endocrine disorder is controversial, as is its therapeutic management. Six patients with this particular combination of disorders were treated with lidoflazine: a new anti-anginal drug with anti-arrhythmic activity. All six patients returned to sinus rhythm on lidoflazine treatment although still hyperthyroid and remained in sinus rhythm during the follow up period ranging from 5 to 14 months. This occurred independently of antithyroid treatment. Some evidence is put forward that dysrhythmias and most commonly chronic atrial fibrillation are triggered off by hyperthyroidism or other disorders but that they are maintained by permanent cardiac damage due to arteriosclerosis, hypertension, coronary heart disease or rheumatic valve disease.

Successful chemical cardioversions and maintenance of sinus rhythm can be obtained independent of the thyroid function. Our results confirm the anti-arrhythmic activity of lidoflazine.

Propranolol in the surgical management of thyrotoxicosis

Forty-nine thyrotoxic patients prepared for partial thyroidectomy with the beta-adrenoceptor blocking drug, propranolol, and iodine are compared with 42 patients prepared with carbimazole and iodine. The age and sex distribution of the two groups were comparable, but patients with obstructive airways disease and possible cardiac insufficiency were excluded from preparation with propranolol. The mean duration of preoperative treatment with propranolol was 40 days, compared with 89 days for carbimazole. Propranolol treated patients had lower pulse rates before and after operation. The serum PB(127)I values immediately before and after operation were higher in the propranolol group than in the carbimazole group, but were the same in both groups one and four months after operation. The incidence of hypothyroidism at one year after operation was 30% in the carbimazole prepared patients and 31% in the propranolol patients. Serum calcium levels were higher in the propranolol group at the time of operation. No adverse effects from the use of propranolol and at operation the thyroid gland prepared with propranolol was firmer, less friable, more easily mobilised and less likely to bleed than the gland prepared with carbimazole. There is, consequently, less risk of damage to the parathyroid glands and recurrent laryngeal nerves. However, the basal metabolic rate remains high on propranolol therapy and very careful supervision is advised.