[Impact of age on mortality in patients with acute traumatic spinal cord injury requiring intensive care]

OBJECTIVE

To evaluate the impact of age (<or≥65 ans) on hospital mortality in traumatic spinal cord injury requiring intensive care.

DESIGN

Retrospective, monocenter.

PATIENTS AND METHODS

A total of 131 patients greater or equal to 15 years (<65 years, n=109 and ≥65 years, n=22) was analyzed (cervical, n=71; thoracolumbar, n=60), over a 10 years period (1998-2008). The hospital and long-term mortality were studied. The risks factors of death were searched by a uni- and multivariate analysis. Intensive care unit (ICU) discharge and long-term neurological recovery, and long-term functional independence measure (FIM) were assessed.

RESULTS

Hospital mortality was increased in patients greater or equal to 65 years (41% vs 6%, P<0.001) and long term mortality was not different between the two groups (31% vs 12%, P=0.150). The risks factors of death were age (HR=3.44; IC 95%: 1.53-7.72, P=0.028), previous coronary disease (HR=3.64; IC 95%: 1.25-10.65; P=0.018) and fall injury (HR=2.40; IC 95%: 1.15-5.00, P=0.020). Among survivors, incompletes forms (Frankel B, C, D, E) were significantly more frequent in older patients at ICU discharge and long term follow up. At long term, FIM was similar in the two groups except a better sphincter control in patient greater or equal to 65 years.

CONCLUSION

Mortality rate of older people (≥65 years) were greater than those in younger people, mainly caused by an increased hospital mortality. Among survivors, the neurological recovery was better in patients' greater or equal to 65 years, and was associated with a functional status at least comparable than in the youngest patients.

[Bilateral traumatic dissection of the renal arteries]

The bilateral dissection of the renal arteries is uncommon after blunt trauma. The clinical symptoms are scarce and inconstant. The diagnosis is based on contrast-enhanced computed tomography with intravenous contrast and angiographic examination is required only if an endovascular revascularization is envisaged. We reported here, an exceptional case of bilateral traumatic dissection of the renal arteries associated with acute renal failure. The delayed revascularization does not allow the recuperation of a renal function.

Factors associated with multidrug-resistant bacteria in secondary peritonitis: impact on antibiotic therapy

Secondary peritonitis includes community-acquired and nosocomial peritonitis. These intra-abdominal infections have a common pathogenesis but some microbiological differences, particularly with respect to the type of bacteria recovered and the level of antimicrobial susceptibility. This report describes a prospective observational study of 93 consecutive patients with secondary peritonitis during an 11-month period. Community-acquired peritonitis accounted for 44 cases and nosocomial peritonitis for 49 cases (post-operative in 35 cases). Fifteen multidrug-resistant (MDR) bacteria were recovered from 14 patients. In univariate analysis, the presence of MDR bacteria was associated significantly with pre-operative and total hospital lengths of stay, previous use of antimicrobial therapy, and post-operative antimicrobial therapy duration and modifications. A 5-day cut-off in length of hospital stay had the best specificity (58%) and sensitivity (93%) for predicting whether MDR bacteria were present. In multivariate analysis, only a composite variable associating pre-operative hospital length of stay and previous use of antimicrobial therapy was a significant independent risk-factor for infection with MDR bacteria. In conclusion, knowledge of these two factors may provide a more rational basis for selecting initial antimicrobial therapy for patients with secondary peritonitis.

Évaluation prospective de trois méthodes de positionnement de la sonde nasogastrique en réanimation

OBJECTIVE

Evaluation of three methods (aspiration of gastric fluid, pH measurement of gastric fluid, and insufflation of air) in order to determine the right position of the nasogastric (NG) tube.

STUDY DESIGN

Prospective, observational study in an intensive care unit.

PATIENTS AND METHODS

All patients requiring a NG tube were included. Since the NG tube was inserted three tests were successively performed: aspiration of gastric fluid, pH measurement of the gastric fluid, and auscultation over the epigastrium of air injected through the NG tube. The feasibility and the results obtained for each test were noted and compared to chest X-ray, considered as the reference. Chest X-ray classified the complications as major or minor.

RESULTS

A total of 419 NG tube (202 decompressive NG tube and 217 gastric feeding tube) were analysed in 280 patients. Malpositions of the NG tube were observed in 10% (majors, n=11 and minors, n=31). Aspiration of gastric fluid and pH measurement were not sensible (77% and 49%, respectively) and not specific (38% and 74%, respectively). Insufflation of air was sensible (96%) but not specific (17%). The combination of the three methods did not improve the sensibility and specificity. Two complications were only detected by chest X-ray (one insertion in the intrapleural space, and one pneumothorax).

CONCLUSION

None of the test evaluated, alone or associated, was sufficient to avoid chest X-ray. Moreover the occurrence of two potential and serious complications only detected by chest X-ray increase this assertion.

Traitement par la protéine C activée : expérience à propos de 23 patients dans un contexte périopératoire

OBJECTIVE

To evaluate the use of activated C protein (ACP) in a Surgical Intensive Care Unit.

STUDY DESIGN

A prospective observational study.

PATIENTS AND METHODS

All patients receiving ACP during 20 months in the operative period.

RESULTS

Twenty-three patients were treated by ACP. The origin of sepsis was peritonitis (n = 14), infected pancreatitis (n = 3), mediastinitis (n = 2), one urologic sepsis, one facial cellulitis, one catheter related infection, and one postoperative pneumonia. In two cases, the peritonitis was associated with a pleuretic infection, and in two other cases with parietal cellulites. Mean age was 69+/-13 years. Severities evaluated by SAPS II, LODS were 59+/-13 and 7+/-3, respectively. Mean number organ dysfunction was 3.3+/-1.0. Septic shock was present in 91% with concomitant use of catecholamines for a mean period of 87+/-64 hours. Bacteraemia was present in 43% of the patients. A treatment with hydrocortisone was associated in 52% of the patients. The ICU and hospital lengths of stay were 15+/-16 days, and 34+/-38 days, respectively. Mortality at day 28 was 35%. Two significant bleeding were observed, one requiring red blood cell transfusion and the other one a surgical control of the bleeding associated with red blood cell transfusion.

CONCLUSION

With global management of severe sepsis, including the use of activated C Protein, this prospective observational study showed a 30% reduction of the predicted mortality by SAPS II scoring without significant increase of bleeding episodes in a surgical context.

[Cardiac arrest outside hospital: initial and subsequent cardiological management]

The prognosis of cardiac arrest outside hospital is directly related to the initial management. The aim of this work was to evaluate the characteristics of the initial and subsequent cardiological management of victims of cardiac arrest outside hospital with a retrospective analysis of data from the SAMU 35 (Emergency Medical Service, IIIe et Vilaine region) in the period April 1998 - April 2002.

RESULTS

533 non-traumatic cardiac arrests outside hospital were reported in 532 patients (average age 63 +/- 17, 73% male). The cardiac arrest occurred at home in 77% of cases. The initial cardiac rhythm documented was asystole in 63% of cases, ventricular fibrillation (VF) in 30% ventricular tachycardia (VT) in 1% and electromechanical dissociation in 6%. A cardiac aetiology was presumed in 294 (69%) of the 424 resuscitated patients. Among these, 22% (66/294) were admitted to coronary care units, 11% (31) left hospital alive, 8% (24) with no neurological sequelae. The survival rate for patients with cardiac arrest outside hospital in the presence of a witness and for whom the initial rhythm was VF or VT was 21%. The patient's age (<60 years)[OR: 1.05; CI 95%: 1.02-1.07; p < 0.001], rapid arrival of the SAMU (<10 min) [OR: 5.68; CI 95%: 1.42-22.7; p = 0.01] and resuscitation by the witness (OR: 8.26; CI 95%: 3.28-20.83; p < 0.001) were factors predictive of survival in a multivariate analysis. Coronary heart disease remains the principal cause of cardiac arrest in patients admitted to cardiology units (68%), with a recent coronary thrombosis shown in 40% of patients undergoing angiography (16/40).

CONCLUSION

the prognosis of cardiac arrest outside hospital remains bleak, with a mortality of 90%. The survival rate is higher if the initial management is optimal, associated with bystander resuscitation and an immediate emergency service response allowing rapid defibrillation. Diagnosis and management of acute coronary syndrome in a cardiological setting must be integrated into the strategy.

[Hepatorenal syndrome: from physiopathology to treatment]

OBJECTIVES

Data synthesis on physiopathology and treatment of hepatorenal syndrome (HRS).

DATA SOURCES

Data were searched in the Medline database from 1975 to 2002 using the following key-words: hepatorenal syndrome, ascite, cirrhosis and portal hypertension.

DATA EXTRACTION

Publications from 1986 to 2002 were selected depending on the quality of their methodology and their pertinence. One publication from 1975 was kept.

DATA SYNTHESIS

Hepatorenal syndrome is a common and severe complication of patients with advanced liver cirrhosis with ascites. It is a functional renal failure due to intense vasoconstriction of the renal circulation secondary to an intense splanchnic vasodilatation. Two types of HRS are differentiated mainly by the speed and the magnitude of the renal failure. Liver transplantation remains the best treatment but is rarely applicable because of the short survival after diagnosis. In the last few years, new therapy have been developed, vasoconstrictor drugs which mainly elicit their effects on the splanchnic circulation as vasopressin and principally its analogues ornipressine and terlipressine are effective in improving renal function and could act as bridge for liver transplantation. The place of the transjugular intrahepatic portosystemic shunt remain to be evaluated.

CONCLUSION

Prognosis of patients with HRS remains poor but the pharmacologic treatment by terlipressine has improved the prognosis particularly in order to wait liver transplantation.

[The measurement of end-tidal carbon dioxide (PETCO2) is not a significant parameter to monitor in patients with severe traumatic brain injury]

PURPOSE

To evaluate the agreement between end-tidal carbon dioxide (PETCO2) and arterial CO2 (PaCO2) in patients with traumatic brain injury and to document the course of the (PaCO2-PETCO2) gradient over time.

METHODS

Twenty one traumatic brain injury patients (Coma Glasgow Scale < or = 8) were included in this prospective observational study over a period of six months. Simultaneous determinations of PaCO2 and PETCO2 (by infrared capnometry) were recorded. Agreement between PaCO2 and PETCO2 was determined by the statistical method described by Bland and Altman. Changes in PETCO2 over time were compared with changes in PaCO2. Factors likely to explain a gradient superior to +/- 4 mmHg were explored.

RESULTS

One hundred and eleven data pairs were obtained. The bias was 5.5 mmHg with a precision of 5.1 mmHg and limits of agreement ranged from -4.5 mmHg to 15.5 mmHg. The latter exceeded the predefined limits of agreement established to determine interchangeability between methods (+/- 4 mmHg). PETCO2 and PoCO2 changed in opposite directions in 20% of 90 consecutive measurements. Only the duration of ventilation was found to be significantly associated with a gradient superior to +/- 4 mmHg.

CONCLUSIONS

In this selected population of patients with severe traumatic brain injury, measurements of PETCO2 and PaCO2 are not interchangeable. Further the PoCO2-PETCO2 gradient is not stable over time and cannot predict variations of PaCO2. The use of PETCO2 instead of PaCO2 could be deleterious in patients in whom strict control of PaCO2 values is required.

[Digestive hemorrhage originated elsewhere]

We report the case of splenic subcapsular haematoma, that happens to a woman after three months. Breaking and fistulation of the splenic haematoma into the gastric cavity and its subsequent evacuation made it first identify as digestive haemorrhage.

Evidence for the need of bedside accuracy of pulse oximetry in an intensive care unit

OBJECTIVE

To compare pulse oximetry saturation (Spo2 with arterial blood gas saturation (SaO2) obtained during clinical routine to determine the optimal lowest reliable value of SpO2 in ventilator-dependent patients before setting up a nurse-directed protocol of FIO2 titration.

DESIGN

Prospective clinical study.

SETTING

Surgical intensive care unit in a university hospital.

PATIENTS

Thirty-three patients with a pulse oximeter probe in whom arterial blood gas was measured with a radial artery line.

INTERVENTIONS

SPO2 was recorded by the nurses and compared with SaO2 obtained by blood gas analysis with a co-oximeter. Two sensors currently used in our surgical intensive care unit and connected to a monitor (HP OmniCare M1165/66A; Hewett Packard, Andover, MA) were tested. In group I, the Durensor DS 100A (Nellcor Puritan Bennett, Pleasanton, CA), a reusable sensor, was used. In group II, the Oxisensor D25L (Nellcor Puritan Bennett), a nonreusable sensor, was used.

MEASUREMENTS AND MAIN RESULTS

In group 1, 64 data pairs were obtained. In this group, SaO2 ranged from 87 to 98% and SpO2 ranged from 92 to 100%. The bias was -1.90% and the limits of agreement ranged from -5.56 to 1.76%. In group 11, 47 data pairs were obtained. In this group, SaO2 ranged from 87 to 99% and SpO2 ranged from 92 to 100%. The bias was -2.49% and the limits of agreement ranged from -6.62 to 1.64%.

CONCLUSIONS

In the range of SaO2 tested, regardless of the sensor used, SpO2 overestimated SaO2. Large limits of agreement were found. Based on this result, the authors concluded that before defining a nurse-directed protocol of FIO2 titration with SpO2, the material used daily must be evaluated. A minimum threshold SpO2 value of 96% in both groups I and II is more reliable to ensure SaO2 > or = 90%.

Non steady state and steady state PKS Bayesian forecasting and vancomycin pharmacokinetics in ICU adult patients

The pharmacokinetics of vancomycin was investigated in adult ICU patients after the first administration and at steady state. Then the predictive performance of a two-compartment Bayesian forecasting program was assessed in these patients by using population-based parameters and three non steady state vancomycin concentrations as feedback information. Finally a prospective investigation was carried out to search potential covariates. At steady state, a significant decrease (around 30%) in clearance (CL) was observed, while creatinine clearance (CLcr) was stable and a significant increase (around 30%) in volume of distribution (V(SS)) was observed. A two-fold increase in elimination half-life was found. CL was weakly correlated with CLcr at onset of therapy and at steady state. The Bayesian program tended to overpredict vancomycin peak and trough concentrations. A larger mean prediction error and a poorer precision were observed when population-based parameter estimates were used (no feedback) compared to feedback prediction, but the differences were not significant. Mechanical ventilation and concurrent opioid therapy may be pertinent covariates of vancomycin pharmacokinetics. The current work has shown that vancomycin pharmacokinetics in ICU patients displayed a significant variability and a significant change in both clearance and distribution during the course of therapy. Further investigation is necessary to clarify these findings. Moreover, the use of the Bayesian forecasting PKS program in our patients led to a prediction with low bias but rather poor precision. This outcome highlights the need to implement a population modeling approach, to determine the vancomycin pharmacokinetic parameters and covariates in our ICU patients, and to apply this information to provide more accurate concentration predictions.

-Curative and preventive antibiotic therapy in infective endocarditis-

Durack's criteria, including echocardiographic manifestations, are the current standard for the diagnosis of infective endocarditis (IE). The most common microorganisms known to cause IE are streptococci and staphylococci, and therapeutic principles are based on an association of parenteral antibiotics, as far as possible bactericidal and prolonged. Treatment also includes the search for the source of infection and its eradication. IE with negative blood cultures requires special techniques to obtain the causal microorganisms. In about half of the cases, a nosocomial bacteriaemia results in IE in patients with a prosthetic valve. Surgery is mandatory in IE with complications and/or caused by particular microorganisms; surgery is essential in most patients with a prosthetic valve. Although the presence of specific links between some procedures and the occurrence of IE has not been clearly proven, a prevention policy is nevertheless justified, considering the morbidity and mortality. Prophylaxis is indicated in patients with the cardiac conditions at risk for IE. IE prophylaxis prevails over prophylactic antibiotics usually administered for surgery.

[Pressure exerted on tracheal cuffs in intubation in the presence of nitrous oxide]

OBJECTIVE

To compare the time course of endotracheal tube cuff pressures in presence of nitrous oxide (N2O), obtained in a tracheal model with those measured during clinical anaesthesia.

STUDY DESIGN

Experimental and clinical prospective study.

MATERIAL

Twelve brands of low-pressure tracheal tubes.

METHODS

The pressure changes in the cuffs were measured over a three-hour-period in presence of a N2O (50 vol%)/O2 (50 vol%) mixture and mechanical ventilation, the tube being inserted either in a tracheal model or in the trachea of patients during general anaesthesia.

RESULTS

The results obtained in vitro were correlated with those measured in the patients. Therefore the tracheal model is a helpful guide for the choice of endotracheal tubes.

-Pancreatitis after blunt injuries to the abdomen-

Three cases of pancreatitis occurring after a trauma to the pancrease are reported. They emphasize the difficulty of diagnosis at the initial phase of the condition. In all cases, computerized tomography (CT) scan was the main diagnostic method. Applying the same therapeutic strategy for pancreatitis as for other aetiologies facilitated a favourable outcome.

Evaluation of a new semi-continuous cardiac output system in the intensive care unit

PURPOSE

A new semi-continuous thermodilution cardiac output (CCO) system has been developed recently (Opti-Q and Q-vue Abbott critical care system). The aim of this study was to compare the accuracy and reproducibility of this new device with conventional ice-bolus thermodilution cardiac output (BCO).

METHODS

Fifteen critically ill patients who needed pulmonary artery catheterization were prospectively investigated. Eighty seven paired data using BCO and CCO methods were compared. Reproducibility was assessed from 90 BCO and 87 CCO determinations by calculation of the mean standard error (SEM) and according to Bland and Altman methodology.

RESULTS

The BCO and CCO ranged from 2.46 to 11.20 L.min-1 and from 1.75 to 10.05 L.min-1 respectively. Bias (mean difference between BCO and CCO) was null (0.002 L.min-1, P = 0.98), precision (SD of the bias) was 0.74 L.min-1 and the limits of agreement (mean difference +/- 1.96 SD) ranged from -1.45 to 1.45 L.min-1. The threshold to consider two cardiac outputs as different (3 x SEM) was equivalent for BCO and CCO (0.54 and 0.465 L.min-1 respectively). According to the Bland and Altman method, reproducibility of CCO was greater than that of BCO; bias of repeated measurements of BCO and CCO were 0.15 L.min-1 (P < 0.05) and 0.047 L.min-1 (NS), respectively.

CONCLUSION

Compared with BCO, this new device was accurate but cannot be considered as interchangeable regarding the limits of agreement. Reproducibility of CCO was superior to BCO.

Value of early blood Th-1 cytokine determination in predicting severity of acute pancreatitis

BACKGROUND

Early evaluation of the severity of acute pancreatitis (AP) requires measurement of many variables within 48 h after admission. Septic complications (SC) are frequent, and preliminary studies have highlighted the value of prophylactic antibiotherapy; however, single and reliable predictive markers of sepsis are not yet available. The aim of this study was to assess the value of determining early blood Th-1 cytokines and their natural antagonists (interleukin-6 (IL-6), IL-1, IL-1ra, and the soluble form of tumor necrosis factor (sTNF) receptors RI and RII) to predict the severity and SC during AP.

METHODS

Thirty-seven patients with AP were prospectively included; 25 of them had severe AP, including 8 with SC. Serum cytokines were measured 48 h and 72 h after the onset of AP with an enzyme-linked immunosorbent assay. The optimal severity or SC diagnostic thresholds was determined using receiver operative curves.

RESULTS

Severe AP in accordance with the Atlanta criteria were better predicted by C-reactive protein and IL-6 serum determination, albeit these levels could not predict absolutely the death of two patients. In severe AP cases (n = 25) the IL-1 to IL-1-ra ratio was lower in cases further complicated by sepsis ((6+/-4) 10(-3) versus (34+/-13) 10(-3), P < 0.05); moreover, sTNF RI (2497+/-270 pg/ml versus 2133+/-611 pg/ml, P < 0.05) and RII (3751+/-400 pg/ml versus 3045+/-509 pg/ml, P < 0.05) were higher in AP characterized by further SC. The IL-1 to IL-1-ra ratio and IL-1 concentration were dramatically decreased within the first 48 h ((0.4+/-0.4) 10(-3) versus (30+/-11) 10(-3), P < 0.05, and 0.3+/-0.3 versus 15+/-3 ng/l, P < 0.05) in patients with further infection of the pancreatic necrosis (n = 3). The SC diagnosis was better anticipated by an IL-1 to IL-1-ra ratio lower than 5 x 10(-3) or by an sTNF RI higher than 1750 pg/ml and sTNF RII higher than 2750 pg/ml, and the infection of the pancreatic necrosis by an IL-1 concentration <2 ng/l or an IL-1 to IL-1-ra ratio <2 x 10(-3).

CONCLUSION

Besides severity markers, IL-1, IL-1-ra, and sTNF RI and RII should be considered in base-line AP assays and, if confirmed by larger studies, could help to screen patients at risk for SC and candidates for prophylactic antibiotherapy with a good negative predictive value.

[Postoperative autotransfusion and transfusion evaluation in cardiac surgery]

In cardiac surgery, blood retransfusion from the thoracic drainages, though already ancient, still remains controversial either for its quantitative or its qualitative interests. A retrospective study has been conducted, between the 1st january 1992 and the 30th june 1993, over 1.655 consecutive operations. Most of the patients suffered from coronary disease (937) or a valvular disease (605), others had been operated for a combined valvular and coronary revascularization surgery (113). The safety of this technique, guaranteed by strict rules, allowed a "transfusional strategy" which tends to reduce the homologous blood consumption. Twenty-nine percent of all the patients received homologous red cells units and only 23% of the patients operated for a coronary revascularization. This strategy aims to reduce both the risks of blood transfusion and the health cost.

[Transfusion and Jehovah's witnesses. A review of medicosurgical attitudes in a University hospital in 1995]

The aim of this study was to evaluate the attitudes of physicians (anaesthetists + other doctors + surgeons) towards Jehovah's witness patients refusing blood transfusion. Such a situation is not uncommon: 79% of respondents uncountered it. For scheduled surgery in adults, 75% of these physicians (54% of anaesthetists) would accept to lake care of these patients. In case of emergency or unforeseen indication for transfusion, 54% of these physicians (72% of anaesthetists) would administer blood, despite a written transfusion refusal. These figures would be 95 and 97% respectively in children.

[Pneumatic tourniquets in orthopedics]

Pneumatic tourniquets, often used to provide a bloodless operating field, carry a risk of adverse effects. Limb exsanguination by gravitation is less aggressive than by mechanical means. Skin, muscles, nerves and vessels suffer maximally under tourniquet because of mechanical pressure, with both a sagittal force, responsible for compression and an axial force responsible for stretchening. All parts of the limb are therefore affected by ischaemia. The restarting of circulation will also increase lesions at the microcirculatory level, responsible for the "no reflow" phenomena. Transient reperfusion intervals are not necessarily beneficial. These effects will significantly contribute to the post tourniquet sensory motor injuries. The tourniquet increases the risk of sepsis. Tourniquet release allows metabolites from the leg to enter into the circulation, and also carries a risk of pulmonary thromboembolism. Carbon dioxide is eliminated by spontaneous hyperventilation under regional anaesthesia. If not eliminated by an increase of mechanical ventilation during general anaesthesia, it may raise intracranial pressure in head trauma patients. Various chemotactic and cytolytic agents may cause lung injury. Mobilization of blood volume at tourniquet placement and release may have detrimental haemodynamic effects in patients with coronary or cardiac insufficiency. The tourniquet increases arterial pressure after 20 to 25 minutes under general anaesthesia. Regional anaesthesia is considered as the technique of choice for the prevention of "tourniquet hypertension", closely linked to pain and relievable by local anaesthetics. Tourniquet modifies also the pharmacokinetics of anaesthetic and other agents. It generates hyperthermia, especially in children. Prospective and comparative studies did not show any advantage as far as duration of surgery and amount of blood loss are concerned. In order to minimize its side effects, the tourniquet must be used within the frame of a strict procedure, with a well adapted and regularly checked equipment. Duration of ischaemia should be as short as possible and not continue for more than two hours, with a reperfusion of 15 minutes every hour. Local hypothermia seems to be a safe means for decreasing side effects.

Prolongation of spinal anesthesia with bupivacaine-loaded (DL-lactide) microspheres

There is considerable interest in developing a sustained-release local anesthetic formulation to provide long-lasting anesthesia and to decrease systemic toxicity. Bupivacaine (B), 10 mg, loaded in two different types of polylactide microspheres (PLA1 and PLA2) was evaluated after spinal injection and compared with plain bupivacaine (pB), 2 mg. Experiments were performed in six New Zealand rabbits. Duration of motor block was significantly prolonged for PLA1 compared to pB (177.5 +/- 79.5 min vs 44.6 +/- 18.0 min; P < 0.05), as well as for the recovery time (545.0 +/- 299.6 min vs 44.2 +/- 21.5 min; P < 0.05). The duration and recovery were not prolonged for PLA2. Systemic release of B after intrathecal injection was measured from blood samples by using high-performance liquid chromatography. There was no significant difference in maximum B plasma concentration between pB and PLA1 (326 +/- 81 mg/mL vs 321 +/- 57 ng/mL). The time taken to reach the maximum plasma concentration (6.6 +/- 2.6 min vs 41.7 +/- 20.4 min; P < 0.05) was significantly different. This study demonstrated that the use of bupivacaine-loaded (DL-lactide) microspheres can prolong spinal motor block.

[Massive entero-mesenteric infarction. A possible role of ostial stenosis of digestive arteries]

A case is reported of a 35-year-old woman who sustained a massive intestinal infarction requiring a total resection of small intestine and the colon, with a terminal duodenostomy. Preoperative arteriography and intraoperative findings at laparotomy showed a thrombosis of coeliac trunc, superior and inferior mesenteric arteries, originating possibly from a non atheromatous ostial stenosis of these vessels. The blood supply to stomach, duodenum, liver and spleen was maintained through collaterals from diaphragm. Postoperatively a dehiscence of duodenostomy suture occurred with a spontaneous favourable outcome. The closure of external duodenostomy orifice required an endoscopic aspirational gastrostomy. The patient was discharged with the perspective of intestinal transplantation, her nutrition being provided through an ambulatory parenteral nutritional support unit. A symptomatology of chronic mesenteric ischaemia should lead to an angiography of digestive arteries not only with a diagnostic but also a possible therapeutic goal using angioplasty techniques.

Spinal controlled delivery of bupivacaine from DL-lactic acid oligomer microspheres

Bupivacaine-loaded microspheres made from DL-polylactic acid oligomers of different molecular weights (MW 2000 and 9000 g/mol, named PLA 2000 and PLA 9000, respectively) which displayed different in vitro release profiles were administered via the spinal route to rabbits. In comparison to the drug administered as a solution (2 mg as equivalent base), PLA 2000 and PLA 9000 microspheres (10 mg as equivalent base) led to a slower uptake of the drug in the systemic circulation, as suggested by the mean maximal plasma concentrations: 326 +/- 81, 321 +/- 57 and 64 +/- 54 ng/mL, respectively. Pharmacodynamic evaluation of the anesthetic action, by means of intensity and time course of motor blockade, indicated a sustained release. In comparison to the drug solution, the PLA 2000 microspheres led to an increase duration of median maximal blockade (172 min versus 44.5 min). The PLA 9000 microspheres failed to reach maximal blockade as a result of a too low release rate.

[Preoxygenation before induction for cesarean section]

In pregnant women at term, the oxygen reserve is decreased while the oxygen consumption is increased, carrying the risk of hypoxaemia during periods of apnea. Moreover, intubation of the trachea can be difficult. Therefore preoxygenation is of particular importance. The conventional method of preoxygenation consists in a 3-5 min breathing of 100% O2. However, in some obstetric emergencies, there may not be an adequate delay of time available for this technique. Recently, 4 maximally deep inspirations were demonstrated to be as effective as a 5-min inhalation of 100% O2 for preoxygenation. To determine whether these two techniques were equivalent before induction of a general anaesthesia for Caesarean section, 27 pregnant women at term (ASA 1 or 2) were studied. Following premedication with atropin sulfate (0.5 mg), the patients were randomly allocated into two groups. Group A (n = 12) was denitrogenated with 100% O2 for 4 min and group B (n = 15) with 4 maximally deep inspirations of 100% O2 within 30 s. Oxygen was administered at a flow rate of 10 L.min-1 via a non rebreathing anaesthesia system and a tight fitting face mask. Arterial saturation was assessed by pulse oximetry. General anaesthesia was induced with thiopentone (7 mg.kg-1) and succinylcholine (1.5 mg.kg-1). The trachea was intubated without previous ventilation and the delay required for the SpO2 to decrease to 93% was measured. This time was 137.9 +/- 79.2 s (extremes 85-320) in group A and 144.5 +/- 57.3 s (extremes 60-285) in group B respectively. These times were not significantly different.(ABSTRACT TRUNCATED AT 250 WORDS)

[Intracranial insertion of a nasogastric tube in a patient with severe head injuries]

The accident intracranial insertion of a nasogastric tube is a well known complication. We report the case of 19-year-old girl with a severe craniofacial trauma who had a nasogastric tube inserted at the site of the traffic accident. The aspiration gave issue of haemorrhagic fluid. At admission the X-ray of the skull showed the intracerebral penetration of the tube. It was removed but the patient died two days later. The various means of prevention and treatment of this complication are discussed.

[Role of isotopic imaging in intensive care]

The real place of isotopic imaging in intensive care patients remains still unclear. This review aimed to consider the indications of isotopic imaging for improved diagnosis and therapy and to specify its place among the other techniques of exploration. Pulmonary perfusion and ventilation scintigraphies are valuable for the diagnosis of pulmonary embolism (PE). A "high probability" scintigraphy of the lungs ascertains the diagnosis of PE and allows to start a specific treatment without requiring a pulmonary angiography. This is not the case in the presence of a history of previous PE or if the arguments for a PE are only weak. A normal lung scintigraphy eliminates the diagnosis of a clinically significant PE all the more as an exploration of good quality of the lower limb veins remains negative. In the opposite a "non diagnostic" scintigraphy justifies a pulmonary angiography in intensive care patients. The diagnosis of myocardial contusion is made uneasy as the clinical symptoms, the ECG, the cardiac enzymes and the chest X-ray are only of limited value. Isotopic explorations of the heart could provide additional valuable data or be an alternative for 2 D echocardiography. The comparison of CPK-MB concentrations with a myocardial scintigraphy using thallium 201 is given as being very reliable, with positive and negative predictive values higher than 80%. An exploration restricted to the cardiac ejection fractions is only of limited value. In the future, an improvement will perhaps be obtained with tracers such as MIBI labelled with technetium 99m, which allow the simultaneous assessment of myocardial perfusion and the ventricular ejection fractions as well. The localisation of centres of infection, especially when intra-abdominal, remains difficult in intensive care patients. Isotopic imaging, especially the scintigraphies with labelled polynuclears, could allow in combination with conventional imaging techniques (computed tomography and 2 D echocardiography) to prevent from errors in diagnosis. An array of arguments is essential for ascertaining the presence of an abscess. Scintigraphies with leucocytes labelled with indium 111 or technetium 99m are qualified as having a sensitivity and a specificity greater than 90%. The conventional techniques of measurement of the cerebral blood flow (CBF) using xenon 133 require a special equipment or are invasive. Other cerebral tracers, such as cyclic amines (HMPAO) labelled with technetium 99m and administrable by i.v. route, allow the use of a standard tomo-gamma camera, and could be of help in various pathological conditions.(ABSTRACT TRUNCATED AT 400 WORDS)

[Antibiotic prophylaxis in gastroduodenal surgery]

The incidence of postoperative wound infections is increased up to 35% after gastroduodenal surgery, when gastric motility and acidity are decreased, as in case of gastric ulcer or cancer, obstruction, bleeding, antacid therapy. The endogenous flora contaminating the operative-site consists of organisms of the oropharynx and the jejunum and includes anaerobes like bacteroides, aerobes like streptococci, staphylococci, E. coli. Antimicrobial prophylaxis is therefore indicated in these high risk patients. All groups of antibiotics have been used, however 1st and 2nd generation cephalosporins are the most effective. A single dose given intravenously just before anaesthesia is recommended, a second dose is advisable intraoperatively when surgery is prolonged or massive blood loss occurs. Antibiotic prophylaxis is also recommended in gastric bypass surgery for obesity, but remains controversial for percutaneous endoscopic gastrotomy.

Doppler ultrasound assessment of the effects of ketamine on neonatal cerebral circulation

The effects of a single dose of 5 mg.kg-1 of ketamine administered intravenously to 10 critically ill preterm infants prior to epicutaneo-caval catheterization were analyzed using pulsed-wave Doppler ultrasound. The infants weighed between 670 and 1,885 g and their gestational ages ranged from 26 to 33 weeks. Arterial pressure (MAP), cardiac output (CO), transcutaneous oxygen pressure (TcPO2), transcutaneous carbon dioxide pressure (TcPCO2), end-diastolic velocity (EDV), peak systolic velocity (PSV), mean arterial velocity (MAV) of the cerebral anterior artery as well as Pourcelot's resistance index (PRI) were measured before and after injection of the drug. We observed a significant decrease in arterial pressure at 2 min after injection while heart rate and CO did not vary significantly. TcPO2 and TcPCO2, also remained unchanged throughout the period of measurement. EDV, PSV, and MAV did not vary significantly nor did PRI. As this drug provides major comfort to the baby during painful procedures and considerably facilitates difficult thin vessel catheterization, we believe that it may be used in such conditions.

[Severe acute pancreatitis: diagnostic approaches and therapeutic implications]

Diagnosis of acute pancreatitis (AP) can be obtained with a high level of accuracy by clinical assessment and determination of common laboratory parameters such as serum amylase and lipase concentrations. However, the key of an optimal management of patients with AP is based on an early discrimination between interstitial oedematous and necrotizing forms. The former resolves spontaneously whereas parenchymal necrosis acting as a focus for bacteria has a very high severity. In this respect, multifactor prognostic scoring systems and new biological assessments like C reactive protein are valuable methods for forecasting the prognosis of AP. However, these indicators of severity require a full 48 hour period of observation. In order to overcome these drawbacks, other prognostic criteria have been explored based mainly, on laboratory data. The most interesting ones are trypsinogen activation peptides and leucocyte elastase. Finally, the more useful tool is computed tomography (CT). Combined with high dose intravenous contrast agent, it allows an early identification of necrosis. Other goals of computed tomography are an accurate diagnosis of infection by guided needle aspirations and a preoperative recognition of devitalized and infected tissues, which require a careful surgical necrosectomy. A prolonged drainage is always recommended but relative merits of a conventional closed drainage and an open one are controversial. Another therapeutic challenge is gallstone associated to severe pancreatitis. An early stone removal is advocated by some authors but others prefer delayed surgery because of high mortality rates in case of emergency surgery. Delayed surgery until biological parameters of pancreatitis are normalized seems preferable. An early endoscopic sphincterotomy in an attractive alternative method.

[Post-traumatic hemiplegia in a patient with fibromuscular dysplasia of the carotid artery]

A 44-year-old patient, without remarkable medical history, was admitted with a head trauma with initial loss of consciousness and a thoracic trauma. The initial treatment included the insertion of a chest drain for evacuation of a pneumothorax and intrapleural analgesia with bupivacaine. The day after admission, the patient experienced a generalized epileptic crisis, without prodomes. Later, a left proportional hemiplegia with aphasia was recognized. The CT scan obtained immediately after the crisis, as well as the carotid Doppler ultrasonography and echocardiography were normal. The bilateral carotid angiography showed an image of fibromuscular dysplasia of the extracranial segment of the right internal carotid artery. The migration of a carotid thrombus initiated by the trauma was hypothetized. A treatment with a platelet aggregation inhibiting drug was started and associated 20 days later with low molecular weight heparin. The patient recovered a normal motility within 10 days; only the aphasia remained. Trauma of the carotid artery is not a frequent cause of cerebrovascular accident. The occurrence of the latter is favoured by a pre-existing lesion of this artery. This case demonstrates that in a trauma patient not all central nervous system manifestations are initiated by a head trauma.

Modulation of the functional properties of human thyrocytes in monolayer or follicle culture: effects of some anaesthetic drugs

It is well known that some volatile anaesthetic drugs, such as halothane and isoflurane, alter the functions of the human thyroid gland, but the action of other anaesthetic drugs, such as thiopental, midazolam and ketamine, on thyroid function is still unknown. We have investigated the effects of these three drugs on the functional properties of human thyrocytes cultured in monolayers or follicles and stimulated by TSH. Thiopental, midazolam and ketamine induced total suppression or a partial reduction, depending on the dose administered, of cyclic AMP (cAMP), follicular thyroglobulin (Tg) and free tri-iodothyronine (FT3) production. In contrast, free thyroxine levels increased in the medium of thyrocytes cultured as follicles. Small doses of the drugs did not affect thyrocyte production. The inhibiting effect of thiopental, midazolam and ketamine on Tg and FT3 production seems to result from the inhibition of cAMP production and 5'-deiodinase.

Effects of halothane on human and rat hepatocyte cultures

The aim of this study was to investigate direct cytotoxicity to human and rat hepatocytes in primary culture from halothane and compare it with that of isoflurane, which is known to be minimally metabolized and less toxic in vivo. Both human and rat parenchymal cells were isolated by the two-step collagenase perfusion method and after attachment to plastic were incubated with either volatile anesthetic for 24 h. All the cultures were maintained in 20% O2 condition and were not induced prior to anesthetic treatment. Temperature, atmosphere conditions, and anesthetic concentrations were kept constant during the study period. Evaluation of cytotoxicity was based on morphologic, biologic (determination of both extracellular and intracellular lactate dehydrogenase activity), and metabolic (protein synthesis and secretion) end points. Protein synthesis and secretion rates were found to be the most sensitive parameters in hepatocyte cultures from both species. Protein synthesis was inhibited by 18% and protein secretion by 50% in the presence of 1 and 1.25 mM halothane, respectively, in human cell cultures (P less than 0.05). With 1.25 mM halothane intracellular lactate dehydrogenase was also decreased; lactate dehydrogenase leakage and morphologic alterations were detected only beyond 5 mM halothane. By contrast, in rat hepatocyte cultures protein secretion was inhibited by 26% and protein synthesis by 20% in the presence of 0.1 and 0.75 mM halothane, respectively, whereas morphologic alterations and a 37% lactate dehydrogenase leakage increase were observed with the concentration of 1 mM (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

[Fatal maternal streptococcus A infection after cesarean section]

A case is reported of an infection with Streptococcus pyogenes, occurring 24 hours after an elective Caesarean section in a 30 year old woman. She worsened during the first 48 h, with shock (Pasys less than 70 mmHg, pH 7.28) as well as abdominal tenderness and guarding. Laparotomy revealed peritonitis, and subtotal hysterectomy was carried out. Gram positive cocci were found in the peritoneal exudate, with bacterial cultures yielding Streptococcus pyogenes. Histopathological examination of the specimen revealed necrosing endomyometritis with septic thrombophlebitis. During the immediate post-operative period, there were several prolonged episodes of circulatory arrest treated with dobutamine, adrenaline, and noradrenaline. Multiple organ failure occurred during the next five days, despite antibiotic therapy (vancomycin, tienamycin, amikacin) and intensive care. It included jaundice, thrombocytopaenia (10 G.l(-1] adult respiratory distress syndrome (ARDS). A further laparotomy was carried out because of abdominal and thigh cellulitis, with completion of the hysterectomy and bilateral salpingo-oophorectomy. Streptococcus pyogenes was still present in the peritoneal cavity. There followed an improvement, with a return to normal of the platelet count, haemodynamic stability such that vasoactive drugs were no longer needed, and a decrease in the degree of jaundice. However, the ARDS worsened, and the patient died 15 days after the Caesarean section. There have been recent reports of similar cases, suggesting an increase in the virulence of group A streptococci linked to a re-emergence of exotoxin A.