Muscle weakness after muscle relaxants: an audit of clinical practice

Residual muscle weakness after general anaesthesia, assessed using handgrip strength, was audited in a teaching hospital. The relationships between residual weakness, the use of muscle relaxants and patient characteristics were examined. Handgrip strength was measured preoperatively, one hour postoperatively and one day postoperatively using a hand dynamometer in 151 patients having general anaesthesia. Forty-nine patients received no muscle relaxant, 34 patients received vecuronium and 68 received rocuronium. Patients were managed by their anaesthetist according to that anaesthetist's clinical choice. All patients who received muscle relaxants received neostigmine. One hour postoperatively, there was a decline in handgrip strength of 16% for the no relaxant group, 24% for vecuronium and 29% for rocuronium. The degree of weakness for the relaxant groups was unrelated to age (P=0.89) but was strongly influenced by the patient's sex. Almost all of the increased weakness with relaxants was found in the female patients. The mean decline in handgrip strength in the male patients who received either vecuronium or rocuronium was similar to that seen when relaxants had not been used (P=0.40). One hour postoperatively, female patients showed a marked decrease in handgrip strength after both vecuronium and rocuronium (32% and 34% respectively, combined P=0.01). These results suggest that in usual clinical practice at our institution, female patients are more likely to have residual weakness after muscle relaxants.     

Review of pyogenic liver abscess at the Royal Adelaide Hospital 1980-1987

Pyogenic liver abscess is an uncommon condition which carries substantial morbidity and mortality if untreated. A review was undertaken of 31 patients who were admitted to the Royal Adelaide Hospital (RAH) between January 1980 and December 1987 and who were diagnosed as having pyogenic liver abscess. The aims of the study were to review the aetiology, current methods of investigation and treatment of the disease, and to formulate a management plan based on the findings. Hypoalbuminaemia, leukocytosis and elevated alkaline phosphatase were the most common findings. Hyperbilirubinaemia was not a usual feature. Computerised tomography (CT) scanning and ultrasound were the most useful imaging modalities in identification of the abscess. The sensitivity of CT scanning in evaluating the size of abscesses was lower than anticipated and this may lead to a higher than necessary rate of surgical drainage. A case is presented to illustrate this. Most abscesses were secondary and frequently due to extension of infection from biliary structures. Diseases causing diminished resistance to bacterial infection had a significant role in the pathogenesis. The overall mortality rate was 25%. Risk factors increasing mortality included advanced age, multiplicity of abscesses, depressed immune status and the presence of complications due to the abscess. Of patients who survived, four were treated with antibiotics alone, eleven with percutaneous drainage and antibiotics, and eight with surgery and antibiotics. We conclude that patients with hepatic abscesses should be managed initially by CT or ultrasound-guided aspiration. If pus is obtained a percutaneous drain should be inserted into the cavity and systemic antibiotics administered.(ABSTRACT TRUNCATED AT 250 WORDS)     

Increasing numbers of admissions to the adult burns service at the Royal Adelaide Hospital 2001-2004

BACKGROUND: The purpose of the study was to illustrate the increasing trend in the number of adult burns patients admitted to the Royal Adelaide Hospital and attempt to explain it and to describe the burn patients admitted to the Royal Adelaide Hospital in terms of age, sex, origin, cause and burn size, particularly since the increasing trend began, in an effort to identify a particular group or burn cause, which may make up a large proportion of the increasing numbers. METHODS: A retrospective review of 1548 acute burn-injured patients using information from the burns unit database between 1996 and 2004 was carried out. RESULTS: Of 1841 total admissions, 1548 were admitted for acute burn injury. There has been an increase in the number of admissions since 2001 amounting to approximately 20% per annum. The cumulative rise in total admissions 2000-2004 is 107% where the increase in acute burn admission in the same period is 82%. There appears to be no difference whether the patient is from a rural or a metropolitan area. Burns of <10% total body surface area constitute most of the increase and are mainly flame and scald injuries. Chemical and contact burns are proportionately increasing. CONCLUSION: The increase in acute admissions is mainly due to the increasing presentation of smaller burns to the unit. The statewide rural burn education programme and media exposure following the 2002 Bali bombings may have contributed to the increase in acute admissions.     

Anaphylaxis to muscle relaxants. Predictive value of intradermal tests and study of crossed anaphylaxis

37 patients were studied, all of whom presented with anaphylaxis to a muscle relaxant. The diagnosis was made after simultaneous intradermal testing (IDT), human basophil degranulation tests (HBDT) and Prausnitz-Küstner tests (PK) of passive cutaneous anaphylaxis. Three tests were positive in 6 patients, both IDT and PK in 9, and both IDT and HBDT in 8. In 14 patients, the IDT, repeated twice, were positive both times. A search for crossed anaphylaxis to the other muscle relaxants was carried out in all the patients during a second series of tests, a few months to years after the first one. The drugs tested, at dilutions of the pharmaceutical preparation of 10(-3) or more, were: suxamethonium, gallamine, alcuronium, pancuronium, vecuronium, d-tubocurarine. The reliability of IDT in the diagnosis of anaphylaxis is discussed in terms of the small reactive concentration, the producibility of the tests, the one HBDT that did become positive later, and in one case the occurrence of shock by crossed anaphylaxis. Skin reactivity seemed to remain constant with time, so allowing the use of IDT as a diagnostic tool, in cases of old anaphylactoid shocks, occurring during general anaesthetics. The frequency of crossed anaphylaxis was assessed to be about 84%. The sensitivity to one or other drugs varied with each patient. Pancuronium and vecuronium appeared to be the least likely drugs to cause crossed anaphylaxis. The predictive use of these tests is discussed. It is also suggested that muscle relaxants with only one quaternary ammonium group should be used, this chemical characteristic probably reducing the risks of sensitization.     

Study of allergy to general anesthetics and muscle relaxants using the lymphoblast transformation test

This study aims to test the lymphocyte response in normal subjects and patients who presented an anaphylactoid shock to various anaesthetic and muscle relaxant drugs, by using the lymphoblast transformation test (LTT). The results show that, although the LTT is a specific test, which can be carried out in vitro, it is badly adapted to the biological diagnosis of anaphylactic drug accidents on the whole, because of a possible non specific lymphoblastic transformation in controls or, on the contrary, of false negative results in anaphylaxis. As a consequence of this, and some comparative studies, the diagnosis of drug induced anaphylaxis must rely on skin tests, human basophil degranulation test (HBDT) and the Prausnitz-Küstner test.     

A longitudinal study of 100 consecutive admissions for carbon monoxide poisoning to the Royal Adelaide Hospital.

A longitudinal study of one hundred consecutive admissions to the Royal Adelaide Hospital for carbon monoxide poisoning was conducted from 1986 to 1989. Twenty-five patients left hospital with persistent symptoms and signs of this poisoning. Five subsequently recovered. Twenty-four other patients, who were well when they left hospital, did not attend for a review one month after discharge. Extensive neuropsychiatric testing at this time showed 32% (24 of 76) had obvious sequelae of their exposure. Overall, the frequency of neuropsychiatric sequelae in the patients who only received oxygen at atmospheric pressure was 63% (N = 8) on discharge and 67% (N = 6) on one month follow-up. The frequency of sequelae among those who were given one hyperbaric oxygen treatment only was 46% (N = 24) on discharge and 50% (N = 20) on one month follow-up. In contrast, the frequency of sequelae in patients who had two or more hyperbaric oxygen treatments was only 13% (N = 68) on discharge (P less than 0.005) and 18% (N = 50) on follow-up (P less than 0.005). the frequency of sequelae was also significantly greater if hyperbaric oxygen was delayed (P less than 0.05). No markers of severe poisoning could be identified.     

Paediatric day-case surgery: an audit of unplanned hospital admission Royal Hospital for Sick Children, Glasgow

Audit of unplanned hospital admission provides information to guide quality improvement measures and is a crude indicator of quality of care in ambulatory surgery. Our objectives were to re-audit factors relating to this outcome. Previous audit conducted in this unit revealed an unplanned admission rate of 3.7%. Data were collected between April 2000-March 2004. Of 13 592 day surgery patients, 238 (1.8%) unplanned admissions occurred. The admission rate displayed a falling trend and represented a significant improvement over the previous audit (p < 0.001). Unplanned admissions were most commonly caused by nausea/vomiting 23.5% (n = 56), postoperative bleeding 13.9% (n = 34), and unexpected extent/difficulty of procedure 11.8% (n = 28). Of all admissions, 18.5% (n = 44) were following orchidopexy, 16.4% (n = 39) following circumcision, and 12.6% (n = 30) following dental extraction. This audit shows that the unplanned admission rate is low and falling, and compares favourably with other units. Measures have been implemented targeting patients at high risk of admission.     

Anaphylaxis due to suxamethonium in a 7-year-old child: a 14-year follow-up with allergy testing

In 1973 a 7-year-old girl had anaphylactic reactions after two general anaesthetics. In-vitro testing with the leucocyte challenge histamine release test showed a strong response to suxamethonium, and other tests indirectly suggested an allergic mechanism. The conclusion was that this was an allergy to suxamethonium. Further blood was sent for testing against a range of neuromuscular blockers, but the patient was 'lost' until she re-appeared 14 years later as an antenatal patient. In-vitro testing was repeated against suxamethonium and all the available neuromuscular blockers after delivery. The radio-allergosorbent test for allergen-specific IgE antibodies was performed on newly collected serum and that which had been stored for 13-14 years. Skin testing was also performed. The results remain positive and suggest a degree of allergy to all the neuromuscular blockers with the possible exception of vecuronium. The radio-allergosorbent test was negative in the patient's baby.     

Medical care at the Royal Hospital of Natives

After the Conquest, the indigenous populations of New Spain were left unprotected by the new government. Thus the Royal Hospital of Naturals (RHN) was created, offering care to the indigenous population for health and with hospitality, as well as religious aid. However, later solely care was provided. The RHN had great support from the Spanish Crown and became a suitable place for clinical investigation that on the peninsula and in all of Europe was forbidden: the autopsies, that in indigenous population are carried out without sanction, only needing authorization of local authorities for their accomplishment, considering the indigenous as inferior to Spaniards. In addition, the RHN was the best place for foundation of the Royal Surgery School of Mexico in the XVIII century. The contribution of the RHN was the fusion of indigenous medicine with European medicine, increasing the therapeutic resource array, as well as the opportunity of carrying clinic investigation through autopsy's for better clinic correlation, and matchless learning for the era in the art of out surgery, this being an important point in the development of the medicine and surgery of Mexico.     

Interaction of muscle relaxants and local anesthetics at the neuromuscular junction

The effects on neuromuscular (NM) function of combinations of relaxants (d-tubocurarine, pancuronium, and succinylcholine) and local anesthetics (cocaine, procaine, lidocaine, etidocaine, and a quaternized derivative of procaine, procaine methobromide) were investigated using the rat's phrenic nerve--hemidiaphragm preparation. Combinations of ineffective concentrations of NM blocking agents with ineffective concentrations of local anesthetics caused a greater than 90% NM block. Preliminary administration of ineffective concentrations of local anesthetics significantly ( p less than 0.001) decreased the ED50 of NM blocking agents. The administration of ineffective concentrations of NM blocking agents caused a similar decrease of the ED50 of local anesthetics. Concentrations of d-tubocurarine and pancuronium which alone produced partial NM block had additive effects. These findings suggest that the interaction of NM blocking agents and local anesthetics consists of true potentiation caused by the different sites of action of the two types of compounds at the NM junction. The degree of potentiation may be enough to cause clinically significant NM block in patients who at the same time receive high enough doses of both agents. In vitro the NM block caused by the combinations of local anesthetics and NM blocking agents can be reversed by 4-aminopyridine.     

Birmingham hip resurfacing at a mean of ten years: results from an independent centre

We report the findings of an independent review of 230 consecutive Birmingham hip resurfacings (BHRs) in 213 patients (230 hips) at a mean follow-up of 10.4 years (9.6 to 11.7). A total of 11 hips underwent revision; six patients (six hips) died from unrelated causes; and 13 patients (16 hips) were lost to follow-up. The survival rate for the whole cohort was 94.5% (95% confidence interval (CI) 90.1 to 96.9). The survival rate in women was 89.1% (95% CI 79.2 to 94.4) and in men was 97.5% (95% CI 92.4 to 99.2). Women were 1.4 times more likely to suffer failure than men. For each millimetre increase in component size there was a 19% lower chance of a failure. The mean Oxford hip score was 45.0 (median 47.0, 28 to 48); mean University of California, Los Angeles activity score was 7.4 (median 8.0, 3 to 9); mean patient satisfaction score was 1.4 (median 1.0, 0 to 9). A total of eight hips had lysis in the femoral neck and two hips had acetabular lysis. One hip had progressive radiological changes around the peg of the femoral component. There was no evidence of progressive neck narrowing between five and ten years. Our results confirm that BHR provides good functional outcome and durability for men, at a mean follow-up of ten years. We are now reluctant to undertake hip resurfacing in women with this implant.     

Mucocele-like lesions of the breast: an audit of 2 years at BreastScreen Auckland (New Zealand)

It is recommended that mucocele-like lesions be excised to enable differentiation between benign lesions and carcinoma. In addition, ductal carcinoma in situ may be found in close association. A small series of 12 lesions audited at BreastScreen Auckland has shown six benign, one atypical, and five malignant lesions. Although this is a small series, a high rate of associated malignancy has been reported.     

Train-of-four fade of non depolarizing muscle relaxants: an insight into the mechanism of precurarization

This study was carried out to assess the prejunctional effect of non depolarizing muscle relaxants during the onset of neuromuscular blockade using the train-of-four ratio (TR). The prejunctional effect was compared with previous results concerning the ability of the relaxants to prevent suxamethonium-induced fasciculations. Fifty-three adult patients were relaxed with small incremental doses of either alcuronium (0.03 mg.kg-1), atracurium (0.04 mg.kg-1), pancuronium (0.01 mg.kg-1), d-tubocurarine (0.05 mg.kg-1) or vecuronium (0.01 mg.kg-1) during anaesthesia with thiopentone, fentanyl and nitrous oxide in oxygen. The muscle relaxant was given after recovery from an initial suxamethonium blockade needed for tracheal intubation. The evoked integrated EMG response to supramaximal train-of-four (2 Hz) stimulation was recorded every 20 s. TR % was calculated at different first twitch (T1) levels during the onset of neuromuscular blockade. Significant changes occurred at the 100% and 90% T1 levels, alcuronium having the lowest mean TR values. Atracurium, pancuronium and vecuronium gave similar TR values. Results with d-tubocurarine placed it between alcuronium and the others. These train-of-four ratio results were compared with the ability of non depolarizing muscle relaxants to prevent fasciculations. In conclusion, the stronger the train-of-four fade, the greater was the ability of the relaxant to prevent suxamethonium-induced fasciculations. This supports the theory that the blockade of prejunctional cholinergic receptors is the mechanism of action of precurarization.     

Prevalence and causal conditions for amputation surgery in the third world: ten years experience at Dodoma Regional Hospital, Tanzania

This is a partly retrospective study of 252 major limb amputations carried out in regional hospital in Tanzania over a period of ten years mostly by the authors. The paper reports on the aetiology and levels of amputation and identifies prevalence and sex of the amputees. The causes of amputation classified under tumours, vascular diseases, trauma, infections, burns, animal bites, iatrogenic causes, maduromycosis and miscellanea--are discussed with particular reference to the influence of the environment, cultural habits and local customs.