Reducing post-tonsillectomy pain with cryoanalgesia: a randomized controlled trial.

OBJECTIVE/HYPOTHESIS: To evaluate the use of cryoanalgesia in reducing post-tonsillectomy pain. STUDY DESIGN: A prospective, randomized double-blind study of 59 consecutive patients (age range, 8-40 y) undergoing tonsillectomy for recurrent tonsillitis. METHODS: All patients underwent bipolar tonsillectomy. At the completion of the tonsillectomy patients were randomly assigned to a control or a cryotherapy group. The cryotherapy patients had both their tonsillar fossa "supercooled" to between -20 degrees C and -32 degrees C for 1 minute. Patients recorded their pain using a visual analogue scale over the next 10 days. Patients were also monitored for postoperative complications, time until resumption of a normal diet, time back to work or school, and analgesic consumption. RESULTS: The two groups were similar for age and sex. There was a 28.3% reduction in mean pain scores over the 10 days in the cryotherapy compared to the control group. This difference did not significantly depend on the day after operation or time of the day. Cryotherapy patients also returned to work or school, on average, 4 days earlier than controls. There was no significant difference in postoperative complications between the two groups. CONCLUSION: Cryotherapy is a new technique that significantly reduces post-tonsillectomy pain without evidence of causing additional complications.

Treatment of hypothyroidism with once weekly thyroxine.

We compared daily T4 therapy with 7 times the normal daily dose administered once weekly in 12 hypothyroid subjects in a randomized cross-over trial. At the end of each treatment we measured serum free T4 (FT4), free T3 (FT3), rT3, and TSH levels and multiple markers of thyroid hormone effects at the tissue level repeatedly for 24 h. Compared with daily administration, the mean serum TSH before the administration of weekly T4 was higher (weekly, 6.61; daily, 3.92 microIU/mL; P < 0.0001), and the mean FT4 (weekly, 0.98; daily, 1.35 ng/dL; P < 0.01) and FT3 (weekly, 208, daily, 242 pg/dL; P < 0.01) were lower. A minimally elevated serum total cholesterol during weekly administration (weekly, 246.8; daily, 232.6 mg/dL; P < 0.03) was the only evidence of hypothyroidism at the tissue level. Compared with daily administration, the mean peak FT4 following weekly administration of T4 was significantly higher (weekly, 2.71; daily, 1.59 ng/dL; P < 0.0001), as was the mean peak FT3 level (weekly, 285; daily, 246 pg/dL; P < 0.01). None of the tissue markers of thyroid hormone effect changed compared to daily T4, and there was no evidence of treatment toxicity, including cardiac toxicity. During weekly T4 administration, autoregulatory mechanisms maintain near-euthyroidism. For complete biochemical euthyroidism a slightly larger dose than 7 times the normal daily dose may be required.

The relationship between proximal femoral anatomy and osteoarthrosis of the hip.

Proximal femoral anatomy in the anteroposterior plane was assessed by analysis of roentgenograms and the relationship between the anatomy and the pattern of osteoarthrosis of the hip was explored. The neck-shaft angle, the height of the femoral head, and the offset of the femoral head were analyzed and the type of osteoarthrosis classified according to Cameron and McNab. There was a significantly greater neck-shaft angle and a greater head height in the upward and outward migratory group. Patients being treated with total hip arthroplasty who exhibit certain types of proximal femoral anatomy might be expected to have increased acetabular loading and thus greater acetabular and femoral head wear. These data may have significance in the design of femoral components and the choice of implants in patients being treated with hip arthroplasty.

Autonomic responses to carbohydrate ingestion and head-up tilt in elderly subjects with orthostatic hypotension.

To investigate the role of glucose and insulin in the development of hypotension following glucose ingestion in elderly subjects with orthostatic hypotension, the autonomic responses to glucose and xylose ingestion were studied in five elderly subjects with age related orthostatic hypotension (without autonomic failure), five elderly control subjects and three elderly subjects with evidence of autonomic failure. Heart rate, blood pressure, plasma noradrenaline and plasma arginine vasopressin responses to glucose ingestion and to xylose ingestion were investigated. All subjects were supine for 90 min following ingestion of each carbohydrate and were then tilted 45 degrees head-up for 10 min. Blood pressure was maintained in elderly control subjects following ingestion of both carbohydrates and during tilting. The elderly group with orthostatic hypotension, while supine had a fall in systolic blood pressure 60-90 min following both glucose and xylose ingestion. Diastolic blood pressure was lowered 60-90 min after glucose but not xylose. During tilting, blood pressure fell by similar levels following both carbohydrate ingestions; plasma noradrenaline levels after 2 min and plasma arginine vasopressin levels after 10 min tilting were significantly less following glucose ingestion compared to xylose ingestion. The autonomic failure group while supine had a fall in systolic blood pressure 60-90 min following both glucose and xylose ingestion. Diastolic blood pressure was lowered 60-90 min after glucose but not xylose. During tilting, blood pressure fell by similar levels following both carbohydrate ingestion. Plasma noradrenaline and arginine vasopressin levels were unchanged after ingestion of either carbohydrate, and during tilting.(ABSTRACT TRUNCATED AT 250 WORDS)

Betamethasone-induced resistance to neuromuscular blockade: a comparison of atracurium and vecuronium in vitro.

Steroids induce resistance to neuromuscular blocking drugs. Betamethasone-induced resistance to vecuronium has been demonstrated in vitro, and a presynaptic site of interaction has been suggested. This study investigated whether atracurium is similarly affected. Rat phrenic nerve-hemidiaphragm preparations were bathed in a physiologic solution, and one-half were exposed to betamethasone (1 mumol/L). Dose responses were recorded for atracurium (8-13 mumol/L) and vecuronium (2-12 mumol/L) for control and betamethasone-treated preparations. In comparison to control, the betamethasone groups had significantly less depression of muscle contraction force at all concentrations of atracurium (P = 0.0004) and vecuronium (P = 0.002). The calculated ED50 (50% depression of muscle contraction force, expressed as mean +/- SEM) for atracurium was 8.83 +/- 0.62 mumol/L for controls and 11.19 +/- 0.54 mumol/L for betamethasone-treated preparations. The calculated ED50 for vecuronium was 4.72 +/- 0.41 mumol/L for controls and 6.84 +/- 0.66 mumol/L for betamethasone-treated preparations. Betamethasone therefore increased the ED50 for atracurium by 27% and vecuronium by 45%; however, the magnitudes of these differences were not significant (P = 0.74) between the neuromuscular blocking agents. These results indicate that betamethasone-induced resistance to nondepolarizing neuromuscular blockade affects both atracurium and vecuronium to similar degrees in vitro.

Clinical information in psychiatric practice: what do doctors know, what do they think is known and what do they record?

Deficiencies in recording clinical information are a widespread problem in both psychiatry and medicine. Previous studies have not established whether information not recorded in the notes is nonetheless known to clinicians. This study compared both the information known to individual clinicians and that recorded in the notes with previously established criteria. Overall, individual clinicians recalled more information than was recorded in the notes (median values: clinicians 47-63% of criteria; notes 42%) and when all this individual knowledge was pooled, 88% of the preset criteria were satisfied. Consultants, but not more junior staff, recalled significantly more about subsections of the history which they considered to be especially relevant to the management plan for a given patient. Only a third of data not known to clinicians, but thought by them to be recorded in the notes, was actually present. The implications of these findings for clinical audit and medical education are discussed.

Australasian field trials of the Mental and Behavioural Disorders section of the draft ICD-10.

Field trials of the "Mental and Behavioural Disorders" section of the 1987 draft of the ICD-10 have been co-ordinated for the World Health Organisation by a number of regional centres. The design of the field trials and the major features of ICD-10 are briefly discussed. The results of the field trial in the Western Pacific region are described, and compared with the results of the original DSM-III field trials. ICD-10 appears to be an acceptably reliable diagnostic system, and the ratings of its feasibility and utility by participating clinicians suggest that it will be seen as a distinct advance over ICD-9.

Circadian variation of heart rate variability.

STUDY OBJECTIVE: The aim of the study was to examine the circadian variation in heart rate variability and to test the hypothesis that the variation is due to vagal influence. DESIGN: Human subjects, some with vagal neuropathy, underwent ambulatory 24 h electrocardiographic monitoring, the recordings being played back through an analyser which identified and timed successive pulse (R-R) intervals. Heart rate variability was measured for each 30 min period over 24 h as the standard deviation of the successive differences between R-R intervals, which filtered out low frequency components of heart rate variability that were not autonomic in origin. Modelled curves of heart rate variability were compared using analysis of variance. SUBJECTS: The subjects were aged between 33 and 65 years and were matched in three groups for age and sex. There were 11 healthy controls, 12 insulin dependent diabetics and seven alcoholics with vagal neuropathy. RESULTS: A significant circadian variation in heart rate variability was present, characterised by a rise during sleep. Mean heart rate variation was significantly reduced in groups with vagal neuropathy, although the amplitude of the cycle and time of peak variability was not significantly different. The circadian variation was sustained regardless of the degree of vagal neuropathy. CONCLUSIONS: The cycle of heart rate variability is not dependent on vagal interaction. It may be due to fluctuations in sympathetic activity affecting beat to beat variability.

Fine catheter peritoneal cytology for the acute abdomen: a randomized, controlled trial.

A randomized, controlled clinical trial, of sequential design, was undertaken to determine whether fine catheter aspiration cytology of the peritoneal cavity, using the percentage of neutrophils in the sample as the main test marker, reduces errors about urgent laparotomy in patients admitted to a surgical unit with acute abdominal pain. One hundred and forty-four patients with acute abdominal pain were studied. Of these, 26 were excluded because the test was unlikely to be useful and 20 did not consent. Conventional clinical assessment was undertaken and then the subjects were randomly allocated to have a peritoneal cytology test or not. After the test result was made available, the surgeon(s) decided whether to operate or continue conservative treatment. The correct decision was later ascertained by a blinded clinical referee. With the entry of the 98th patient the difference between the groups achieved the 5% significance level. The groups were well-matched in regard to demographic and other variables. The decision about urgent laparotomy was incorrect in only 8.2% of the test patients, compared with 28.6% of the others. It is concluded that fine catheter aspiration cytology of the peritoneal cavity is likely to reduce the numbers of unnecessary or delayed laparotomies when used in most patients admitted with acute abdominal pain.

The relationship between the QT interval and plasma amiodarone concentration in patients on long-term therapy.

We have studied 27 patients on long-term treatment (6-60 months) with amiodarone (dose range 350 mg per week to 2800 mg per week) to ascertain whether the corrected QT interval could predict plasma amiodarone or plasma desethylamiodarone concentration. The patients were assessed on three or four occasions one month apart. There were positive correlations for delta % QTc and plasma amiodarone and delta % QTc and plasma desethylamiodarone. There was approximately a four-fold variation for delta % QTc and plasma amiodarone. This variation was not accounted for by between-occasion variation in the QTc interval, as the coefficient of variation was 2.1%. In six of the patients delta % QTc either decreased or did not change. delta % QTc is not a reliable predictor of plasma amiodarone concentration in the individual patient over time.

Fine-catheter aspiration cytology of peritoneal cavity improves decision-making about difficult cases of acute abdominal pain.

Fine-catheter aspiration cytology of the peritoneal cavity was successfully undertaken in 25 of 27 hospital inpatients with acute abdominal pain because it was not clear whether they required urgent laparotomy. Cytological specimens were prepared by the cyto-sieve technique. The main test criterion was the percentage of neutrophils in the peritoneal cell sample. The decision before the test about urgent laparotomy was correct in 14 of the 27 patients, whereas the decision after the test was correct in 26 of the 27 patients (p = 0.001). 4 patients were saved unnecessary laparotomy and 8 further delay in laparotomy.

Neonatal thyroid function: prematurity, prenatal steroids, and respiratory distress syndrome.

Indices of thyroid function were measured in 97 preterm infants at birth and at 5, 10, and 15 days of age. Triiodothyronine uptake, free thyroxine index, thyroxine, free thyroxine, triiodothyronine, reverse triiodothyronine, and thyroxine binding globulin values at birth correlated with gestational age, whereas thyroid stimulating hormone values did not. Treatment with steroids prenatally had no apparent effect on thyroid function at birth or postnatally. Infants developing respiratory distress syndrome had normal values for all indices at birth. These infants had significantly lower thyroxine, free thyroxine index, free thyroxine, and triiodothyronine values at 5 days of age, while thyroid stimulating hormone values remained normal. This alteration in thyroid function was interpreted as being secondary to respiratory distress syndrome. Gestational maturity and respiratory distress syndrome, if present, must be taken into account when evaluating thyroxine variables in preterm infants, whereas measurement of thyroid stimulating hormone as the screen for congenital hypothyroidism circumvents these considerations.