Can teaching methods based on pattern recognition skill development optimise triage in mass-casualty incidents?

BACKGROUND: Patient's triage is a key element of mass-casualty incidents (MCIs) response, although performance of healthcare professionals in triage proved to be poor. It was assessed if specific teaching methods based on pattern recognition skill development can help healthcare students to improve their performance in triage. METHODS: 128 medical and nursing students have been assessed while performing triage during disaster medicine exercises. Half of them (group 1) had previously been involved in a standard curriculum. The remaining half (group 2) benefited from specific teaching methods based on pattern recognition skill development. RESULTS: Performance of group 2 was significantly higher compared with group 1 (p<0.01). Group 2 had a lower overtriage rate. CONCLUSIONS: Disaster medicine courses based on pattern recognition skill development improve triage performance of healthcare students during simulated MCI. This study may have a high impact on healthcare students and professionals' education in the perspective of MCIs preparedness and response.

[Anaesthetic considerations for interventional radiology]. / Anesthésie pour imagerie interventionnelle.

OBJECTIVE: To describe the new procedures applied for interventional radiology leading to specific anaesthetic care and organization. DATA SOURCE: Record of references from national and international journals in Medline. STUDY SELECTION: All types of articles were selected including prospective studies, practice guidelines, reviews and case reports. DATA SYNTHESIS: During interventional radiology, anaesthesia should be adapted to the duration of the procedure, the pain induced by the radiologist, the position of the patient and its medical status. General anaesthesia would be preferred for long procedures, requiring total immobility. Locoregional anaesthesia can be proposed for some cases. Sedation associating hypnotics (propofol, midazolam, sevoflurane) and opioids (alfentanil, remifentanil) is commonly used according to different schemes, as discontinuous boluses, continuous infusion, target controlled intravenous sedation or patient controlled sedation. Monitoring of temperature and diuresis may be useful for long procedures. Haemodynamic monitoring (arterial catheter, central venous pressure) and haemostatic monitoring may be necessary for interventional neuroradiology and endovascular stenting. Radiofrequency and laser procedures are often painful, requiring the choice of adequate analgesic regimen. Hydratation associated with acetylcysteine seems to be able to prevent contrast induced nephropathy in patients with risk factors for chronic renal insufficiency. CONCLUSION: As advances in interventional radiology are obvious, general organisation as well as anaesthetic procedures should be adapted to these specific techniques.

[Interest of the Mini Mental State Examination to detect cognitive defects after cardiac surgery]. / Intérêt du Mini Mental Test dans le dépistage des troubles cognitifs après chirurgie cardiaque.

INTRODUCTION: Cognitive defects are frequently described after cardiac surgery. They occur in 30 to 79% cases. They might be related to the use of a cardiopulmonary bypass (CPB). They are poorly evaluated in clinical practice. OBJECTIVES: To evaluate the usefulness of the Mini Mental State Examination (MMSE) to screen patients scheduled for cardiac surgery. STUDY DESIGN: Prospective, open study. PATIENTS AND METHODS: 100 consecutive patients undergoing coronary artery bypass or valvular replacement under CPB were enrolled in the study. The MMSE was performed the day before surgery and five days later. Patients exhiting a postoperative defect> or =4 points were compared to those without changes or with improved results. RESULTS: 73 patients completed both tests. The mean score decreased postoperatively in 12 patients (15%). They were older (70+/-8 years), had longer CBP durations (128+/-50 min) and the lowest temperatures (30 degrees C+/-3) compared to the other patients. At the opposite, five patients (9%) improved their scores. CONCLUSION: These results entourage to carry out a more strict follow-up for the oldest patients in cardiac surgery. The MMSE could be systematically integrated to the pre and postoperative screening. The detection of cognitive dysfunction should lead to address the patient to a geriatrician for a prolonged follow-up.

Fatal bile pulmonary embolism after radiofrequency treatment of a hepatocellular carcinoma.

Radiofrequency is increasingly used to manage liver tumors. This report describes the case of a 74-year-old man who received two courses of percutaneous radiofrequency thermal ablation for a hepatocellular carcinoma over a 4-month period. He subsequently required computed tomography-guided drainage for an area of intrahepatic necrosis. During the procedure, hemobilia developed, followed by respiratory distress and collapse. The diagnosis of bile pulmonary embolism was established on the basis of high biliary acid concentrations in pulmonary fluid aspiration and blood plasma. Radiofrequency thermoablation provides local control of advanced liver tumors with low recurrence and morbidity. However, this interventional procedure risks damage to liver parenchyma involving vascular and biliary structures, which may lead to biliary-venous fistula and possible bile emboli.

Fatal form of phaeochromocytoma presenting as acute pyelonephritis.

We report the case of a young man who presented with a clinical picture of acute pyelonephritis. Within 3 h of admission, the patient developed acute respiratory distress associated with tachycardia and shock, and he was transferred to the intensive care unit. Mechanical ventilation of the lungs and symptomatic treatment were started immediately. Abdominal ultrasound revealed the presence of an adrenal tumour with central necrosis indicating a probable phaeochromocytoma. There was no sign of pyelonephritis. Ventricular fibrillation followed by asystole occurred soon after admission. The suddenness of the patient's death did not allow time for further investigation and therapy. The severity of the clinical signs was probably related to a massive release of catecholamines because of necrosis of the tumour, which may have been worsened by the diagnostic procedures performed to investigate the clinical symptoms and signs of acute pyelonephritis.

Bronchial blocker compared to double-lumen tube for one-lung ventilation during thoracoscopy.

BACKGROUND: Video-assisted thoracoscopic surgery (VATS) requires one-lung ventilation with a properly collapsed lung. This study compared the Broncho-Cath double-lumen endotracheal tube with the Wiruthan bronchial blocker to determine the advantages of one device over the other during anaesthesia with one-lung ventilation for thoracoscopy. METHODS: Thirty-five patients undergoing VATS were randomly assigned to one of two groups. Sixteen patients received a left-sided double-lumen tube (DLT) and nineteen a Wiruthan bronchial blocker (BB). The BB group was subdivided in two: BB in the right mainstem bronchus (BBR) for right-sided VATS (9 patients), BB in the left mainstem bronchus (BBL) for left-sided VATS (10 patients). The position of the devices was checked using a fibreoptic bronchoscope. The following variables were measured: 1) number of unsuccessful placement attempts; 2) number of malpositions of the devices; 3) time required to place the device in the correct position; 4) number of secondary dislodgements of the devices after turning the patient into the lateral decubitus position. The quality of lung deflation was evaluated by the surgeons who were blinded to the type of tube being used. RESULTS: The number of unsuccessful placement attempts was one in the DLT group (1/16), three in the BBL group (3/10) and none in the BBR group (0/9). The number of malpositions was significantly greater in the BBL group (10/10) compared to the DLT group (2/16) and to the BBR group (1/9) (P<0.001). The time (mean+/-SD) required to place a BBL was 4.21 min+/-1.28, significantly longer than the time required to place a DLT (2.26 min+/-0.55, P<0.0006) or a BBR (2.41 min+/-0.53, P<0.008). The difference in placement time between DLT and BBR was not significant. The number of secondary dislodgements was one in the DLT group, one in the BBR group and none in the BBL group (NS). The quality of lung deflation was judged excellent or fair in all patients in the DLT and the BBL groups and poor in 44% of the patients in the BBR group. CONCLUSION: It took significantly longer to place a left BB than a DLT (P<0.0006) or a right BB (P<0.008). The number of initial malpositionings of the left BB was significantly greater than in the other groups (P<0.001). The quality of lung deflation was better in the BBL and in the DLT groups than in the BBR group. We conclude that for routine use during left-sided VATS, the use of a DLT is preferable to a left BB because of its greater ease of placement. For right-sided VATS, DLT and right BB showed the same facility of placement but the DLT provided a better quality of lung deflation.

Vitamin K metabolism in a patient resistant to vitamin K antagonists.

We investigated various pharmacokinetic and pharmacodynamic parameters in a 63-year-old man, resistant to warfarin, fluindione, acenocoumarol and phenprocoumon. Daily doses of up to 30 mg of the long-acting phenprocoumon yielded a drug concentration of 85 mg/l (usual range 1-5 mg/l) but the international normalized ratio remained around 1. The plasma half-life of phenprocoumon was approximately 350 h (normal 120-150 h). Thus, the resistance was not due to malabsorption or to an accelerated metabolism of the drug. The level of vitamin K1 (1,202 ng/l) was insufficient to induce resistance. Decarboxyprothrombin concentrations were low, demonstrating that the gamma-carboxylation of the precursors of the vitamin K-dependent coagulation factors was not effectively reduced. The concentration of vitamin K epoxide, normally increased under oral anticoagulation, correlated to the vitamin K concentration (r2 = 0.77) but the quotient epoxide/vitamin K remained 4-fold lower than that of 22 warfarin-sensitive patients, suggesting an absence of blockade of the vitamin K reductase by phenprocoumon. This resistance to all the molecular forms of the vitamin K antagonists is most likely due to a reduced affinity of the drugs to a mutant vitamin K reductase.

Urine benzodiazepines screening of involuntarily drugged and robbed or raped patients.

OBJECTIVE: This study involved 35 patients who claimed to have been drugged before being robbed or raped, despite urine negative toxicologic screening by immunoenzymatic methods. The urines were frozen for further investigations, including enzymatic hydrolysis of urinary conjugates, liquid-solid extraction and, finally, immunoenzymatic screening of concentrated urine extract. METHODS: Urine benzodiazepines were analyzed by immunoenzymatic assay before and after enzymatic hydrolysis combined with extraction. RESULTS: On direct immunoenzymatic screening, 17 of the 35 urine samples were benzodiazepine positive. Enrichment of preserved specimens improved the detection threshold from 200 ng/mL to 50 ng/mL and 10 of the 18 negative urines became positive. CONCLUSION: This method allowed us to demonstrate the benzodiazepines in half of previously negative urine samples. Benzodiazepine screening is particularly problematic because of low dosage, rapid elimination, failure to detect conjugated metabolites by immunoenzymatic reagents and high threshold of sensitivity for certain substances.

Hemodilution is an effective treatment for reperfusion edema after lung transplantation.

A 38-year-old patient underwent left single-lung transplantation for end-stage histiocytosis with secondary pulmonary hypertension and polycythemia. Despite use of an optimal lung graft and a total ischemia limited to 250 minutes, major pulmonary edema developed postoperatively. Hemodilution resulted in a quick recovery of lung function. We speculate that blood hyperviscosity was a major factor of pulmonary edema in this patient.

[Hypersensitivity and resistance to antivitamins K]. / Hypersensibilité et résistance aux antivitamines K.

During the initial phase or during treatment with oral anticoagulants, hypersensitivity or resistance may be observed, requiring significant changes in prescribed dosage. A thorough knowledge of the mode of action of vitamin K and its antagonists is useful to improve understanding of unexpected response to oral anticoagulant therapy. These abnormal responses may be due to poor compliance to treatment by the patient, insufficient or excessive vitamin K intake, interference with other drugs or abnormalities of the hepatic enzymes which are the target of oral anticoagulant drugs. The search for a cause is justified by the risks associated with these abnormal responses. It must be rigorously undertaken with an accurate interrogation, use of an anticoagulation monitoring leaflet and, if necessary, measurement of plasma concentrations and pharmacokinetics of the anticoagulant drug.

Nausea and vomiting after gynaecological surgery: a meta-analysis of factors affecting their incidence.

A total of 1442 patients who had major gynaecological surgery were recruited into three multicentre studies using a standard general anaesthetic technique in order to assess the efficacy of various doses of orally administered ondansetron in the prevention of postoperative nausea and vomiting. A total of 1257 patients were included in this analysis: 420 received oral formulations of placebo and 212, 296 and 329 received ondansetron 1, 8 and 16 mg, respectively. The following factors were measured in these studies and were considered to have a possible influence on the proportion of patients experiencing postoperative nausea and vomiting: age of patient; volatile anaesthetic; intraoperative dose of fentanyl; postoperative dose of morphine; country; anaesthesia duration; neuromuscular blocker; neuromuscular block antagonist; premedicant; recovery time; type of surgery; antiemetic treatment; body weight. Using a process of elimination based on logistic regression techniques, the factors found to be the most important influences on the frequencies of nausea and vomiting were antiemetic treatment, type of surgery, neuromuscular blocker, country, volatile anaesthetic and age. A statistically significant interaction between type of surgery and age was observed. Adjusted probabilities of nausea and vomiting were obtained from the model, including all the above factors, together with the type of surgery by age interaction. Ondansetron 8 mg showed the smallest adjusted probability of nausea (0.54) and vomiting (0.34) and placebo the greatest (nausea 0.75, vomiting 0.61). A similar pattern of adjusted probabilities over neuromuscular blocking agents was seen for nausea and vomiting, with the greatest occurring in patients receiving pancuronium (nausea 0.74, vomiting 0.57) and the least in patients receiving alcuronium (nausea 0.59, vomiting 0.38).(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of oral ondansetron in the prevention of postoperative nausea and vomiting after major gynaecological surgery performed under general anaesthesia.

The efficacy and safety of ondansetron in preventing postoperative nausea and vomiting following major gynaecological surgery was evaluated in this multicentre, double-blind study. A total of 243 patients were randomised to receive three doses of oral ondansetron 8 mg or matching placebo at 8-hourly intervals, with the first dose being given an hour before surgery. A standard general anaesthetic technique was employed throughout. Nausea, vomiting and safety assessments were performed continuously during the 24 h postrecovery period. Of the 237 patients evaluated for efficacy, significantly fewer ondansetron 8 mg treated patients (65/117; 56%) experienced postoperative nausea and/or vomiting compared with placebo-treated patients (94/120; 78%) during the study period (p < 0.001). In addition, ondansetron 8 mg reduced the severity of nausea (p < 0.001) and the total number of vomiting episodes experienced (p < 0.001). Overall, ondansetron 8 mg was well tolerated and effective in preventing postoperative nausea and vomiting in this surgical setting.

Pharmacokinetics of intravenous fusidic acid in patients with cholestasis.

The pharmacokinetics of fusidic acid and 3-ketofusidic acid were investigated in cholestatic and noncholestatic patients after intravenous administration of single and multiple doses of 500 mg of sodium fusidate. The patients, all with low serum albumin levels, were divided into three groups. Group I consisted of six noncholestatic patients; group II consisted of nine mildly cholestatic patients with mild hepatic impairment (conjugated bilirubin, 47 mumol liter-1; alkaline phosphatase, 280 IU liter-1; gamma-glutamyltranspeptidase, 190 IU liter-1); group III consisted of six benign intrahepatic cholestatic patients with high isolated conjugated hyperbilirubinemia (98.1 mumol liter-1). Assays were performed by high-pressure liquid chromatography. At steady state, the mean peak concentrations in serum were 63.7, 44.9, and 92.2 micrograms ml-1 in groups I, II, and III, respectively; over a dosage interval, areas under the concentration-time curve were 411.1, 238.7, and 603.4 micrograms.h ml-1 and the mean body clearances were 0.34, 0.53, and 0.25 ml min kg-1 in groups I, II, and III, respectively. The accumulation ratio of fusidic acid increased from 2.8 and 2.4 in groups I and II to 4.2 in group III. At steady state, the ratios of the areas under the concentration-time curve from 0 to 8 h for 3-ketofusidic acid/fusidic acid were 0.11, 0.09, and 0.10 in the three groups, respectively. Only very small amounts of fusidic acid and 3-ketofusidic acid were found in urine. These results substantiate the following hypotheses. In group I and II patients the clearance is higher than that in healthy volunteers because of the increased free, unbound fraction of fusidic acid, a consequence of lower serum albumin concentrations, resulting in increased distribution in tissue and hepatic metabolism. In group III patients, the higher bilirubinemia results in competition with fusidic acid for the limited glucuronidation, thus compensating for the increased elimination with fusidic acid because of the low serum albumin concentration. These results suggest that fusidic acid can be administered normally even to patients with high bilirubinemia because the postoperative serum albumin concentration is usually low.

[Preoperative normovolemic hemodilution using erythropheresis]. / Hémodilution normovolémique préopératoire par érythrophérèse.

Normovolaemic haemodilution was carried out by erythropheresis by the Blood Bank, 24 to 72 yours before surgery, using a plasmapheresis device. A special disposable haemodilution kit was used, with one plasma and three red cell collection bags and CPD as anticoagulant. Plasma was replaced by 4% albumin. One to 4 red cell packs with 75% haematocrit was obtained and stored for 10 days. This technique is indicated for surgery with an expected blood loss between 1,000 and 1,500 ml, or when the patient cannot be included in a preoperative blood donation programme. The contra-indications are the same as those of intentional normovolaemic haemodilution. This technique has been used in 101 patients due to undergo orthopaedic surgery. Compared with standard haemodilution bags, the advantages of this technique are the excellent asepsis of this product, its 10 days storage and high haematocrit, and the absence of anaesthetic drugs within the bags as well. This technique does not interfere with haemodynamic conditions during anaesthesia; it saves time for both anaesthetists and surgeons. In the authors' experience, this technique has in part replaced the more usual technique.

Continuous infusion of high-dose metoclopramide: comparison of pharmacokinetically adjusted and standard doses for the control of cisplatin-induced acute emesis.

Metoclopramide was administered by continuous infusion to two groups each of 14 patients on chemotherapy, randomized to receive either doses adjusted to individual pharmacokinetic parameters or doses adjusted as usual to body weight. The mean plasma concentration at the end of the infusion in the adjusted group was 1.01 mg.l-1, close to that aimed for (1.20 mg.l-1). It was significantly different from that in the other group. v 0.54 mg.l-1. Antiemetic efficacy, defined as less than or equal to 2 emetic events in the 24 h following cisplatin, was similar in both groups (being found in 12/14 (86%) and 10/14 patients (71%), respectively). Analysis of the cumulative percentage of responders according to plasma concentration showed a clear plasma concentration-effect relationship. Routine MCP pharmacokinetic dosage adjustment is not indicated, but this therapeutic approach can be used to optimize antiemetic therapy in poor responder patients.

[The association of continuous peridural anesthesia with general anesthesia. Apropos of 2 accidents]. / Association anesthésie péridurale continue et anesthésie générale. A propos de deux accidents.

Continuous lumbar epidural anaesthesia combined with light general anaesthesia provides optimal anaesthetic conditions to realize major lower abdominal or pelvic surgical cases. However this technique may cause haemodynamic alterations due to the important vasoplegia and to the potential myocardial toxicity of the local anaesthetics. The authors report two accidents associated with this technique, one of them with lethal outcome.

[Emergency cesarean section]. / Césarienne urgente.

Emergency cesarean section is a frequent high risk procedure. Systematic third trimester anesthesia consulation is of great value. The main problem is difficult intubation. It may be prevented by scoring patients according to Mallampati and Wilson, and by more frequent use of fiberoptic techniques. Perfect knowledge of a failed intubation drill is mandatory. Monitoring of ETCO2, SpO2 and curarisation comes in addition to basic monitoring. Special conditions as toxemia, major bleeding, allergies, maternal circulatory arrest are reviewed. Suggested protocols for general and locoregional techniques are presented.

[Heart arrest during spinal anesthesia for transurethral resection of the prostate. Apropos of a case]. / Arrêt cardiaque au cours d'une rachianesthésie pour résection transurétrale de prostate. A propos d'un cas.

We report a cardiac arrest in a 66 years healthy patient during a spinal anesthesia for a transurethral resection of prostate. The accident occurred one hour and fifteen minutes after the subarachnoidal injection of hyperbaric lidocaine 80 mg, at the end of surgery, but before any postural change. We attempt to elucidate the surgical or anesthesiologic precipitating factors that lead to the cardiac arrest in this patient. However, there was no real etiology that formally explained the genesis of the accident. This case is to add to a series of recently published accidents that occurred during spinal anesthesia in healthy patients.

[Postoperative intensive care after thymectomy for myasthenia gravis]. / La réanimation post-opératoire après thymectomie pour myasthénie.

The post-operative management of the myasthenic patient after thymectomy through sternotomy has changed in the last decades. After years of routine preoperative tracheostomies followed by routine prolonged intubation nowadays it is possible to wean the patients from the ventilation and to extubate them early after surgery while reintroducing the acetylcholinesterase inhibitors therapy. A series of 15 patients operated on between 1985 and 1988 for removal of thymic rests or thymoma is presented and confirms this evolution. The clinical and gazometric criteria allowing an early weaning from the ventilator are analyzed. However certain patients with the most severe forms of myasthenic still need prolonged ventilatory support.