Emergence from anesthesia in the prone versus supine position in patients undergoing lumbar surgery.
BACKGROUND: Conventional supine emergence in patients undergoing prone lumbar surgery frequently results in tachycardia, hypertension, coughing, and loss of monitoring as the patient is rolled supine. The prone position might facilitate a smoother emergence because the patient is not disturbed. No data describe this technique. METHODS: Fifty patients were anesthetized with fentanyl, nitrous oxide, isoflurane, and rocuronium. By the conclusion of surgery, all patients achieved spontaneous ventilation and full reversal of neuromuscular blockade in the prone position, as the volatile anesthetic level was reduced. Baseline heart rate and mean arterial pressure were recorded. Patients were then randomized at time 0 to the supine (n = 24) or prone (n = 21) position as 100% oxygen was administered. Patients in the supine position were then rolled over, while those in the prone position remained undisturbed. Heart rate, mean arterial pressure, and coughs were recorded until extubation. Tracheas were extubated on eye opening or purposeful behavior. RESULTS: When compared with the supine group, prone patients had significantly less increase in heart rate (P = 0.0003, maximum increase 9.3 vs. 25 beats/min), less increase in mean arterial pressure (P = 0.0063, maximum increase 4.8 vs. 19 mmHg), less coughing (P = 0.0004, 7.0 vs. 23 coughs), and fewer monitor disconnections (P < 0.0001). Time to extubation from time 0 was similar (4.0 vs. 3.7 min, prone vs. supine). No one required airway rescue. There was no significant difference in need for restraint (three prone, four supine). CONCLUSIONS: Prone emergence and extubation is associated with less hemodynamic stimulation, less coughing, and less disruption of monitors, without specifically observed adverse effects, when compared with conventional supine techniques. (+info)
Antibiotics for coughing in general practice: a qualitative decision analysis.
BACKGROUND: In family practice, medical decisions are prompted most often by complaints about coughing. There is no single yardstick for the differential diagnosis of respiratory tract infections (RTIs). In 80% of cases, the excessive use of antibiotics in the treatment of RTIs is caused by the prescription behaviour of GPs. OBJECTIVE: Our aim was to explicate GPs' diagnostic (and therapeutic) decisions regarding adult patients who consult them with complaints about coughing, and to investigate what determines decision making. METHODS: Exploratory, descriptive focus groups were held with GPs. Hypotheses were generated on the basis of 'qualitative content analysis'. Results. Twenty-four GPs participated in four semi-structured group discussions. In order to differentiate RTIs from other possible diagnoses, less likely diagnoses were not ruled out explicitly. In the case of suspected RTI, there was a low degree of certainty in the differentiation between RTIs (e.g. between bronchitis and pneumonia). Clinical signs and symptoms, which determine the probability of disease, often left GPs with reasonable diagnostic doubt. In the end, the decision whether or not to prescribe antibiotics was taken. GPs' prescription behaviour was also determined by doctor- and patient-related factors (e.g. having missed pneumonia once, patient expectations). The 'chagrin factor' explains why these factors lead to a shift in the action threshold, in favour of antibiotics. CONCLUSION: This inductive research method enabled the generation of meaningful hypotheses regarding the complex decision processes pursued by GPs. The authors are developing an educational intervention that builds on these findings, focusing on the prescribing decision. (+info)
Predictors of an antibiotic prescription by GPs for respiratory tract infections: a pilot.
BACKGROUND: Antibiotics are over-prescribed for respiratory tract infections in Australia. OBJECTIVES: The aim of this study was to describe the clinical predictors of GPs' prescribing of antibiotics. METHODS: We used Clinical Judgment Analysis to study the responses of GPs to hypothetical paper-based vignettes of a 20-year-old with a respiratory tract infection. The nature of four symptoms and signs (colour of nasal mucous discharge; soreness of the throat; presence of fever; and whether any cough was productive of sputum) was varied and their effect on prescribing measured using logistic regression. RESULTS: Twenty GPs participated. The nature of each symptom and sign significantly predicted prescribing of an antibiotic. Cough productive of yellow sputum; presence of sore throat; fever; and coloured nasal mucus increased the probability of an antibiotic being prescribed. CONCLUSIONS: GPs are influenced by clinical signs and symptoms to use antibiotics for respiratory infections for which there is poor evidence of efficacy from the literature. (+info)
Kainic acid lesions to the lateral tegmental field of medulla: effects on cough, expiration and aspiration reflexes in anesthetized cats.
We have tested the hypothesis that neurons of both the ventral reticular nucleus and the adjacent parts of the lateral tegmental field (LTF) may be important for the production of motor programs associated with cough, expiration and aspiration reflexes. Our studies were conducted on non-decerebrate, spontaneously breathing cats under pentobarbitone anesthesia. Dysfunction of the medullary LTF region above the obex, produced by uni- or bilateral injections of kainic acid (a neurotoxin), regularly abolished the cough reflex evoked by mechanical stimulation of both the tracheobronchial and laryngeal regions and in most cases also the expiration reflex induced from the glottal area. However, some electrical activity still occurred in the neurogram of the recurrent laryngeal nerve during probing the laryngeal and glottal regions. Interestingly, the aspiration reflex elicited from the nasopharynx regularly persisted, although with lower intensity after the LTF lesion. Nevertheless, successive midcollicular decerebration performed in four cats also abolished the aspiration reflex. These experiments demonstrate the importance of medullary LTF neurons for the normal occurrence of cough and expiration reflexes. One possible explanation for the elimination of these expulsive processes is that the blockade of the LTF neurons may remove an important source of a facilitatory input to the brainstem circuitries that mediate cough and expiration reflexes. In addition, the potential importance of the mesencephalic reticular formation for the occurrence of the aspiration reflex and the role of the LTF in modulating both the eupnoeic breathing and the blood pressure are also discussed. (+info)
Visceral leishmaniasis during childhood in southern Greece.
Records were reviewed of 82 immunocompetent children (median age, 2. 5 years) from southern Greece who were diagnosed with visceral leishmaniasis from 1986 through 1998. Forty-nine (58%) patients originated from the city of Athens; of them, 46 (94%) lived by hills bordering the city. The median interval from the onset of symptoms to admission was 10 days. Fever and splenomegaly were observed in >95% of the patients. Thrombocytopenia was the most frequent hematological finding (80%). All patients were treated with meglumine antimonate; 20 (24%) of them were partially treated on an outpatient basis. Rapid clinical response was noted in all patients but one. Five patients relapsed; 3 responded to reintroduction of meglumine antimonate, 1 responded to liposomal amphotericin B, and 1 underwent splenic artery ligation. We conclude that pentavalent antimonials remain the first choice of treatment for visceral leishmaniasis in immunocompetent children in areas where resistance has not become a problem. It is possible to treat affected patients with outpatient administration of these agents, making them feasible options for therapy. (+info)
Predicting influenza infections during epidemics with use of a clinical case definition.
Combined pharyngeal and nasal swab specimens were collected from 100 subjects who presented with a flu-like illness (fever >37.8 degrees C plus 2 of 4 symptoms: cough, myalgia, sore throat, and headache) of <72 hours' duration at 3 different clinics in the province of Quebec, Canada, during the 1998-1999 flu season. The rate of laboratory-confirmed influenza infection was 72% according to cell culture findings and 79% according to the results of multiplex reverse-transcription polymerase chain reaction (RT-PCR) analysis (85%, influenza AH3; 15%, influenza B). All subjects for whom these results were discordant (negative culture and positive PCR) presented with a temperature > or =38.2 degrees C as well as 3 or 4 of the symptoms in the clinical case definition. Stepwise logistic regression showed that cough (odds ratio [OR], 6.7; 95% confidence interval [CI], 1.4-34.1; P=.02) and fever (OR, 3.1; 95% CI, 1.4-8.0; P=.01) were the only factors significantly associated with a positive PCR test for influenza. The positive predictive value, negative predictive value, sensitivity, and the specificity of a case definition including fever (temperature of >38 degrees C) and cough for the diagnosis of influenza infection during this flu season were 86.8%, 39.3%, 77.6%, and 55.0%, respectively. (+info)
Capsaicin induced cough in cryptogenic fibrosing alveolitis.
BACKGROUND: Cough is a common and troublesome symptom in cryptogenic fibrosing alveolitis (CFA) but the mechanisms responsible are not known. The cough threshold to inhaled capsaicin is increased in asthma and chronic obstructive pulmonary disease (COPD) where lung volumes are increased, but the relationship between cough response and symptom intensity has not been studied in CFA where lung volumes are reduced. METHODS: Capsaicin challenge tests were performed on 15 subjects with proven CFA and 96 healthy controls. Symptoms, as assessed by daily diary card cough score and by visual analogue scale (VAS), were related to the capsaicin sensitivity (C5) and compared with lung volumes. Volume restriction was produced in a group of 12 normal healthy subjects by a plastic shell tightly strapped to the chest wall. Capsaicin challenge tests were performed in these subjects, both strapped and unstrapped, to determine whether volume restriction altered the cough reflex. RESULTS: The median C5 response in normal subjects was more than 500 microM compared with 15.6 microM in those with CFA (p<0.001). The C5 response of the CFA patients was not related to symptoms of cough (whether measured by diary card or by VAS), nor was it related to percentage predicted total lung capacity (TLC) or forced vital capacity (FVC). Volume restriction of normal subjects with chest strapping successfully restricted lung volumes to levels similar to that of the CFA patients but did not change the sensitivity to capsaicin. CONCLUSIONS: The cough reflex measured using capsaicin is markedly increased in patients with CFA. This increase is not the result of alterations in the deposition of inhaled particles of capsaicin brought about by volume restriction. It could be related to reduced lung compliance leading to sensitisation of rapidly adapting receptors, other mechanical changes, or to destruction of pulmonary C fibres secondary to interstitial inflammation. The capsaicin test may be a useful method of objectively monitoring cough propensity in CFA. (+info)
Intravenous opioids reduce airway irritation during induction of anaesthesia with desflurane in adults.
Desflurane is not used for the induction of anaesthesia despite its favourable pharmacokinetic characteristics because it causes airway irritation. We investigated whether pretreatment with i.v. narcotics reduced unwanted effects. One hundred and eighty adults were randomized to three groups (60 per group) to receive i.v. saline, fentanyl 1 microgram kg-1 and morphine 0.1 mg kg-1, respectively, before inhalational induction with desflurane in nitrous oxide and oxygen. Mean time to loss of response to commands was 4.0 min, without significant differences between groups. The incidence of coughing was greater (25%) in the control group than in the fentanyl (5.0%) and morphine groups (8.3%). The incidence of apnoea was 20.0% in the control group versus 13.3 and 5.0% in the fentanyl and morphine groups, respectively. Laryngospasm developed in 11.7% of controls compared with 3.3 and 1.7% in the fentanyl and morphine groups, respectively. More patients in the control group had excitatory movements (46.7%) than in the fentanyl (16.7%) and morphine (8.3%) groups. These results demonstrate that i.v. opioids reduce airway irritability significantly during inhalational induction with desflurane in adults. (+info)