PubMed Health⌕ Search

Biomedical subjects

C Lentschener

Publications and source records attributed to C Lentschener.

At least 19 recordsLinked to original sources

[Bilateral tension pneumothorax after retrieval of transtracheal jet ventilation catheter].

We report a bilateral tension pneumothorax which occurred in a 36-year-old man after high-frequency jet ventilation (HFJV) for panendoscopy. The patient had been treated with radiotherapy and chemotherapy two years ago for an oropharyngeal adenocarcinoma, and by surgery for a recurrence. The incident occurred after a cough episode triggered by the withdrawal of the Ravussin transtracheal catheter. We are discussing the risk factors and the mechanisms of pneumothorax during HFJV with special emphasis on trapping and lung fibrosis.

Adenocarcinoma↗

Predictive value of preoperative transthoracic echocardiography in patients undergoing adrenalectomy for pheochromocytoma.

BACKGROUND: Adrenalectomy for pheochromocytoma is a life-threatening procedure. Few echocardiographic assessments have been reported in patients undergoing adrenalectomy for pheochromocytoma. METHODS: Sixty-three consecutive patients undergoing adrenalectomy for pheochromocytoma underwent routine preoperative M-mode and two-dimensional echocardiography, and Doppler examination. Abnormal echocardiographic findings were defined as left ventricular dilatation or dysfunction (left ventricular percentage fractional shortening < 30%), and/or left ventricular wall motion abnormalities, and/or left ventricular hypertrophy (left ventricular mass index > 110 g m(-2) in women and >134 g m(-2) in men) and/or valvular abnormalities. Physical characteristics, daily urinary metanephrine and normetanephrine excretions, preoperative functional limitation, pre-existing congestive heart failure, type and duration of surgery, and haemodynamic instability in the intra and postoperative periods were compared in patients with normal and abnormal echocardiographic findings. RESULTS: Twenty-four out of 63 patients were found to have abnormal preoperative echocardiography. There was no difference between patients with normal and abnormal preoperative echocardiography as regards to the investigated criteria, except for pre-existing self-reported functional limitation and chest pain suggesting coronary artery disease. CONCLUSIONS: The relevance of routine preoperative echocardiographic examination in patients scheduled for adrenalectomy for pheochromocytoma, who have no cardiac symptoms or clinical evidence of cardiac involvement, is questionable.

Adrenal Gland Neoplasms↗

Comparison of cardiac output measured with echocardiographic volumes and aortic Doppler methods during mechanical ventilation.

OBJECTIVE: To compare two transesophageal echocardiographic methods of cardiac output and stroke volume measurement in mechanically ventilated patients. DESIGN: Prospective clinical study. SETTING: Operating room (group I) and intensive care unit (group II) in two university hospitals. PATIENTS: Fifteen deeply anesthetized patients undergoing gynecological laparoscopy for sterility (group I) and 40 patients with septic shock (group II). INTERVENTIONS: Transesophageal echocardiography with modification of hemodynamic conditions. MEASUREMENTS AND RESULTS: Left ventricular (LV) volumes, cardiac (CI) and stroke index (SI) were measured with two methods using either LV volumes or aortic Doppler. These values were significantly lower in group I compared to group II. Using ANOVA and paired t-tests, there were no significant differences between the two methods of measurement. Correlation between these methods was better in group II than in group I, although not significantly so. In group I, bias for CI measurements was low (0.05 l/min per m(2)), with a weak agreement in terms of the 95% confidence interval (-1.17; 1.06 l/min per m(2)) compared to the mean values obtained with both methods (1.3 l/min per m(2)). In group II, bias for CI measurements was lower (0.2 l/min per m(2)). Agreement was weak, regarding 95% confidence intervals (-1.7; 1.3 l/min per m(2)) compared to the mean values (3 l/min per m(2) with the LV volumes method and 3.2 l/min per m(2) and with the Doppler method). CONCLUSIONS: Cardiac output and stroke volume can be measured from LV volumes in mechanically ventilated patients, yielding relevant information. However, the accuracy of LV volume measurements is not excellent compared to the aortic Doppler method. Thus, this latter technique should still be considered as the gold standard.

Analysis of Variance↗

[Survey of office space and computer availability offered to full time practitioners in departments of anaesthesia and intensive care of French university hospitals].

INTRODUCTION: Office space and computer facilities offered to medical practitioners in departments of anaesthesia (DA) belonging to university hospitals in metropolitan France in 2002 were surveyed. METHOD: A questionnaire was mailed to the 72 heads of DA belonging to university hospitals in metropolitan France in order to assess: (1) the number of full time anaesthesiologists sharing each office; (2) whether a computer was provided to all full time anaesthetists who required one; (3) the adequacy of the offices in terms of the DA's needs; (4) the subjective appreciation of the comfort level of the DA office space when compared to other departments within the institution; (5) whether an office space with a computer was specifically reserved for fellows. RESULTS: Sixty-two replies were received (86.1%). Among full time anaesthesiologists surveyed:only 21.8% occupied an office alone; 1.2% had no office; 36.5, 21.7, 8.2, 3.4, 3.9, 3.2% shared one office with 1, 2, 3, 4, 5, more than 5 colleagues, respectively; 25.8% had a personal computer. Fifty percent of DA surveyed did not reserve a specific office for fellow's need; 75.8% of the offices surveyed were evaluated as being of inadequate comfort level; 64.5% of the offices surveyed were evaluated at a lower comfort level when compared to the office space of other departments within the institution. CONCLUSION: A high response rate was obtained. DA were found to be insufficiently provided with offices and computer facilities in french university hospitals. Such a situation, which is both surprising and questionable in an industrialised country, warrants a debate.

Anesthesia Department, Hospital↗

What anaesthetists need to know about viral hepatitis.

BACKGROUND: Viral hepatitis is a major world-wide public health issue. An increasing number of virus hepatitis carriers with acute or chronic hepatitis at all stages of the disease will be referred to anaesthetists. An update of what anaesthetists should know about viral hepatitis was believed to be warranted. METHODS: The present review focuses on (a) diagnosis criteria and main biological and clinical patterns of acute and chronic hepatitis, and (b) extrahepatic manifestations, and adverse effects resulting from specific drug therapy likely to influence anaesthetic care. RESULTS: Elective surgery should be postponed and any medications that could be harmful to the liver should be disregarded in patients suspected of having acute viral hepatitis. A prothrombin time decrease to less than 50% (INR > 1.75) is the first sign of acute severe liver failure. Extrahepatic manifestations resulting mainly from small- and medium-sized vessel alteration, and adverse effects caused by specific drug therapy are associated with chronic viral hepatitis and are likely to alter anaesthetic care. A titrated anaesthesia should be provided and agents not eliminated by the liver should be favoured. Vasopressor therapy should be administered early to control a systemic intraoperative blood pressure decrease associated with a high cardiac output. Prophylactic antibiotics should take into consideration the risk of translocation of gut bacteria to the systemic circulation. Prophylactic guidelines of hepatitis nosocomial transmission should be respected. CONCLUSIONS: Anaesthetists are likely to play a key role in immediate acute hepatitis and chronic hepatitis perioperative assessment and care.

Anesthesia↗

Remifentanil-propofol vs. sufentanil-propofol: optimal combinations in clinical anesthesia.

BACKGROUND: Two opioid regimens, computer-simulated to provide optimal general anesthesia in combination with propofol, were compared using clinical criteria. METHODS: Fifty patients undergoing thyroid surgery were blindly, prospectively and randomly allocated to receive either (a) i.v. remifentanil (1.5 micro g kg-1, followed by 0.2 micro g kg-1 min-1) or (b) i.v. sufentanil (0.2 micro g kg-1 followed by 0.2 micro g kg-1 h-1). Remifentanil infusion was stopped at the last skin suture. Sufentanil infusion was stopped 30 min before the end of surgery. Intravenous propofol was titrated to keep BIS at 50+/-5. Remifentanil and sufentanil groups were compared with regards to (a) propofol delivery, (b) hemodynamic and recovery variables, and (c) effect-site propofol levels during a steady-state period for effect-site remifentanil and sufentanil levels. P<0.05 was significant. RESULTS: Groups were similar in demographic data; types and durations of surgery; total propofol consumption; and response, extubation and emergence times. During the steady-state period for the opioid delivery, the remifentanil and sufentanil effect-site levels were 5.3 ng ml-1 and 0.18 ng ml-1, respectively (potency ratio=30). In both opioid groups, in accordance with previous computer-simulations, the effect-site propofol concentrations remained (a) within a narrow range unaffected by surgical stimuli, (b) significantly smaller in the remifentanil group than in the sufentanil group, but (c) smaller than expected from previous computer-simulations. More patients required ephedrine following induction of anesthesia in the remifentanil compared with the sufentanil group. CONCLUSIONS: The present clinical trial conducted in thyroid surgery is consistent with previous computer-simulated opioid-propofol combinations with respect to intraoperative and recovery variables. Effect-site propofol ranges were, however, lower than expected.

Adult↗

Bispectral index changes following etomidate induction of general anaesthesia and orotracheal intubation.

BACKGROUND: Etomidate-associated hypnosis has only been studied using standard clinical criteria and raw EEG variables. We conducted a BIS-based investigation of etomidate induction of general anaesthesia. METHODS: Thirty hydroxyzine-premedicated ASA I patients were randomly allocated to receive etomidate 0.2, 0.3, or 0.4 mg kg(-1) intravenously over 30 s. The BIS was continuously recorded. A tourniquet was placed on a lower limb to record purposeful movements and myoclonia. Tracheal intubation was facilitated using rocuronium 0.6 mg kg(-1) when the BIS value was 50. The times to disappearance of the eyelash reflex, to a decrease in the BIS to 50, and to tracheal intubation were compared. The BIS values 30 s following tracheal intubation, and mean arterial pressure (MAP) and heart rate (HR) at all time points were also recorded. RESULTS: The BIS value decreased to 50 for tracheal intubation with no purposeful movement in all but one patient in the 0.2 mg kg(-1) group. There was no difference between the etomidate groups (0.2, 0.3, and 0.4 mg kg(-1)) in regards to time to loss of the eyelash reflex (103 (67), 65 (34), 116 (86) s, P=0.2), or to a decrease in BIS to 50 (135 (81), 82 (36), 150 (84) s, P=0.1). Also, the BIS value 30 s after intubation (41 (10), 37 (4), 37 (4), P=0.4), and plasma etomidate concentrations (161 [29-998], 308 [111-730], 310 [90-869] ng ml(-1), P=0.2) did not differ between groups. The time to loss of the eyelash reflex was 12-140 s shorter than the time to a decrease in BIS to 50 in three patients in each group who received etomidate 0.2 and 0.4 mg kg(-1), and in four patients who received 0.3 mg kg(-1). No awareness was recorded. MAP and HR increases following tracheal intubation were comparable between groups. CONCLUSIONS: Etomidate induction doses do not predict the time for BIS to decrease to 50 as this variable varies markedly following three etomidate dose regimen.

Adult↗

[Survey of bibliographic facilities offered in departments of anesthesia and intensive care of French univeristy hospitals].

OBJECTIVES: We assessed bibliographic facilities offered in departments of anaesthesia (DA) belonging to university hospitals in metropolitan France. METHODS: We mailed a questionnaire to the 76 heads of DA belonging to university hospitals in France to assess: a) which journals dealing with anaesthesia, analgesia, and critical care were available, on site, for consultation; b) whether a medical library existed within the institution; and c) whether all bibliographic informations required by any DA collaborators were charged to the institution. RESULTS: We received 67 replies (87%). High impact factor revues had the widest availability rates--Anesthesiology: 67 DA (100% of responses)--Anesthesia Analgesia: 66 DA (98.5%)--the British Journal of Anaesthesia: 63 DA (94%). The Annales Françaises d'Anesthésie et de Réanimation were available in 66 DA (98.5%). Ten journals in French were variably available--no journal: 1 DA (1.5%)--1 journal: 19 DA (28%)--2 journals: 34 DA (51%),--3 journals: 10 DA (15%)--4 journals: 3 DA (4%). Revues dealing with anaesthesia in specialised surgery were diversely available--neurosurgery: 7 DA (10%)--paediatrics: 10 DA (15%)--obstetrics: 11 DA (16%)--cardiovascular: 26 DA (39%). Revues dealing with pain management, regional anaesthesia or critical care were available in 29 DA (43%), 32 DA (47%), and 59 DA (91%), respectively. The European Journal of Anaesthesiology was available in 40 DA (60%). Thirty-nine DA (58%) took charge of all bibliographic informations required. No medical library existed in 4 university hospitals (6%). CONCLUSION: DA offers a wide variation in bibliographic facilities in French university hospitals.

Anesthesia Department, Hospital↗

Anaesthesia for elective liver resection: some points should be revisited.

Improvement in surgical techniques, technology and perioperative assessment has dramatically simplified the anaesthetic care for elective liver resection. Patients with a non-tumorous healthy liver should only need the usual preoperative assessment. Patients with pre-existing parenchymal liver disease should be specifically assessed for gas exchange impairment, alcoholic or nutritional-associated cardiomyopathy, infection, cirrhosis decompensation, acute alcoholic hepatitis, and kidney impairment. The type of anaesthetic management does not influence the intra- and postoperative courses. Intermittent clamping of the portal vascular triad is better tolerated than prolonged continuous periods of ischaemia--especially in patients with abnormal liver parenchyma. Intraoperative antibiotic prophylaxis must be administered to prevent translocation of intestinal enterobacteria to the systemic circulation in patients with both healthy and diseased livers. Blood-salvage techniques have limited indications in liver resection. Systematic invasive haemodynamic monitoring is no longer warranted. An arterial cannula should only be considered in procedures of long duration and in selected situations likely to cause anticipated circulatory impairment: total liver vascular occlusion, repeat surgery, combined organ resection, and surgery conducted on tumours >10 cm in size or in connection with the vena cava. In a recent large series of liver resections, 60% of patients did not need a blood transfusion, only 2% of transfused patients received >10 units of blood and cirrhosis was not predictive of increased intraoperative bleeding. Postoperative ascites, which always develops at the expense of circulating fluid, is a frequent occurrence in patients with healthy or diseased livers. Intra- and postoperative fluid limitation does not prevent postoperative ascites. Volume expansion, diuretics and vasopressor therapy should be initiated early to prevent kidney failure.

Anesthesia↗

Haemodynamic changes and vasopressin release are not consistently associated with carbon dioxide pneumoperitoneum in humans.

BACKGROUND: Conflicting haemodynamic changes, suggested to be caused by vasopressin release, have been reported during carbon dioxide (CO2) pneumoperitoneum. However, peritoneal stimulations including open surgery cause both a systemic vasopressor response and a vasopressin release, which are suppressed by opiate administration. Also, a decreased venous return of blood to the heart causes vasopressin release. Furthermore, previous haemodynamic assessments of laparoscopic surgery have been conducted using various anaesthetic regimens, which are likely to have caused various haemodynamic effects. We hypothesised that intraoperative haemodynamic and/or humoral changes would not be observed in association with laparoscopic surgery provided that, (a) normovolaemia is continuously maintained using transoesophageal echocardiographic (TEE) assessment, and (b) adequate depth of general anaesthesia is continuously maintained by bispectral index (BIS) monitoring and high plasma Ievel opiate administration. METHODS: Twenty ASA 1 women undergoing laparoscopic surgery received 10 ml. kg-1 lactated Ringer's solution and thereafter were randomly allocated to receive intraoperatively either 8 ng. ml-1 or 4 ng. ml-1 plasma remifentanil concentrations while BIS was maintained at 50+/-5 by isoflurane alteration. The group receiving 4 ng. ml-1 remifentanil was used as control. Expired CO2 was maintained within a 32-38 kPa range throughout the investigation. Complete TEE haemodynamic investigation was performed before pneumoperitoneum (PP) (T1), and during PP horizontal (T2), with a head-up tilt (T3), with a head-down tilt (T4), horizontal (T5), and PP released (T6). Plasma vasopressin, epinephrine and norepinephrine levels were measured at T1, T3, and T6. ANOVA, Student's t-test and Mann-Whitney U-test were used for statistical analysis. RESULTS: Haemodynamic indices and humoral values did not change significantly within and between remifentanil groups throughout the investigation (all P<0.05). CONCLUSION: Continuous adequate depth of anaesthesia and normovolaemia may have prevented both a humoral and a haemodynamic response, initiated in the peritoneum by the contact with CO2 in previous investigations.

Adult↗

Effect of CO(2) pneumoperitoneum on early cellular markers of retinal ischemia in rabbits with alpha-chymotrypsin-induced glaucoma.

BACKGROUND: Increased intraperitoneal pressure in the head-down position is associated with a significant increase in intraocular pressure (IOP) in rabbits with alpha-chymotrypsin-induced glaucoma. Also, the retinal cells are weakened by the induction of increased IOP, and/or glaucoma, even when IOP is controlled by adequate therapy; therefore, these cells need to be protected from any additional aggression. Actin and vimentin are proteins of the retinal cell cytoskeleton that react readily in response to retinal injuries, including ischemia and glaucoma. Early changes in these cytoskeleton proteins determine the morphological changes observed after retinal damage. Therefore, we set out to investigate intracytoplasmic changes in vimentin and actin after a 4-h CO(2) pneumoperitoneum in the head-down position in rabbits with alpha-chymotrypsin-induced glaucoma. METHODS: Twenty-one rabbits with alpha-chymotrypsin-induced glaucoma in one eye received general anesthesia for 4 h in the head-down position and were randomly allocated to have (a) no pneumoperitoneum, (b) a 10 mmHg CO(2) pneumoperitoneum, or (c) a 20 mmHg CO(2) pneumoperitoneum. At the end of the trial, both the right glaucomatous and the left control eyes were enucleated and investigated immunocytochemically for alterations in vimentin and actin, and morphologically for retinal layer disorganization. RESULTS: Except for the preexisting morphological changes induced by glaucoma, both the control and the glaucomatous eyes in all rabbits appeared normal in terms of retinal layer organization and the distribution of intracellular vimentin and actin whatever the intraperitoneal pressure level applied. CONCLUSION: In rabbits with alpha-chymotrypsin-induced glaucoma, a 4-h CO(2) pneumoperitoneum of </=20 mmHg in the head-down position did not induce either retinal layer disorganization or alteration of actin or vimentin.

Actins↗

Haemodynamic changes associated with portal triad clamping are suppressed by prior hepatic pedicle infiltration with lidocaine in humans.

Portal triad clamping (PTC) reduces venous return of blood to the heart. However, the decrease in cardiac index (CI) is associated with an unexpected increase in mean arterial pressure (MAP) and the 40% increase in systemic vascular resistance is greater than anticipated in compensation for the 10% decrease in CI. We hypothesized that a reflex elicited in the peritoneum accounted for this unanticipated haemodynamic response. Twenty patients undergoing liver resection were allocated randomly to have hepatic pedicle infiltration before PTC with either lidocaine 200 mg or placebo. MAP was recorded, and plasma osmolality and plasma concentrations of vasopressin, epinephrine, norepinephrine, dopamine, renin and endothelin were measured. After PTC, MAP increased significantly in the placebo group but decreased significantly in the lidocaine group. Plasma concentrations of vasopressin, epinephrine and norepinephrine increased significantly in the placebo group. Plasma concentrations of vasopressin decreased significantly in the lidocaine group, while plasma concentrations of epinephrine and norepinephrine were unchanged. A subsequent study in eight patients found that neither haemodynamic nor hormonal changes associated with PTC in the placebo group were altered by administration of lidocaine 200 mg i.m. before PTC.

Adolescent↗

Reduction of blood loss and transfusion requirement by aprotinin in posterior lumbar spine fusion.

UNLABELLED: Aprotinin reduces blood loss in many orthopedic procedures. In posterior lumbar spine fusion, blood loss results primarily from large vein bleeding and also occurs after the wound is closed. Seventy-two patients undergoing posterior lumbar spine fusion were randomly assigned to large-dose aprotinin therapy or placebo. All patients donated three units of packed red blood cells (RBCs) preoperatively. Postoperative blood loss was harvested from the surgical wound in patients undergoing two- and/or three-level fusion for reinfusion. The target hematocrit for RBC transfusion was 26% if tolerated. Total (intraoperative and 24 h postoperative) blood loss, transfusion requirements, and percentage of transfused patients per treatment group were significantly smaller in the aprotinin group than in the placebo group (1935 +/- 873 vs 2809 +/- 973 mL per patient [P = 0.007]; 42 vs 95 packed RBCs per group [P = 0.001]; 40% vs 81% per group [P = 0.02]). Hematological assessments showed an identically significant (a) intraoperative increase in both thrombin-antithrombin III complexes (TAT) and in activated factor XII (XIIa) and (b) decrease in activated factor VII (VIIa), indicating a similar significant effect on coagulation in patients of both groups (P = 0.9 for intergroup comparisons of postoperative VIIa, XIIa, and TAT). Intraoperative activation of fibrinolysis was significantly less pronounced in the aprotinin group than in the placebo group (P < 0.0001 for intergroup comparison of postoperative D-dimer levels). No adverse drug effects (circulatory disturbances, deep venous thrombosis, alteration of serum creatinine) were detected. Although administered intraoperatively, aprotinin treatment dramatically reduced intraoperative and 24-h postoperative blood loss and autologous transfusion requirements but did not change homologous transfusion in posterior lumbar spine fusion. IMPLICATIONS: In our study, aprotinin therapy significantly decreased autologous, but not homologous, transfusion requirements in posterior lumbar spine fusion.

Adult↗

The effect of pneumoperitoneum on intraocular pressure in rabbits with alpha-chymotrypsin-induced glaucoma.

UNLABELLED: Increased intraperitoneal pressure is associated with physiological changes including alterations of intraocular pressure (IOP). We have previously shown that IOP is not adversely affected by increased intraperitoneal pressure up to 15 mm Hg in women with no preexisting eye disease. The aim of this study was to measure IOP changes associated with increased intraperitoneal pressure (up to 15 mm Hg) of 2 h duration in 12 rabbits with alpha-chymotrypsin-induced glaucoma. A reliable model of glaucoma was created by injecting alpha-chymotrypsin into the posterior chamber of the right eye in 12 rabbits. Thereafter, 5 of the 12 rabbits with glaucomatous eyes were treated with topical timolol. The left eye was used as a control. During pentobarbital general anesthesia, increased intraperitoneal pressure up to 15 mm Hg was created by intraperitoneal CO2 insufflation. Body temperature and expired CO2 were kept constant throughout the study. IOP measurements were made using an electronic pneumotonometer. IOP, mean arterial pressure, heart rate, and central venous pressure were recorded in head-up and head-down positions before, during, and after increased intraperitoneal pressure. The IOP of both eyes, in both treated and untreated rabbits, increased significantly from baseline only when increased intraperitoneal pressure associated with the head-down position resulted in a significant increase in central venous pressure. However, the IOP increase remained within the diurnal range. The major finding of this study is that, in a reliable model of glaucoma, CO2 pneumoperitoneum was associated with an increase in IOP when a head-down position was combined with pneumoperitoneum. IMPLICATIONS: In rabbits with alpha-chymotrypsin-induced glaucoma, increased intraperitoneal pressure (up to 15 mm Hg) resulted in a significant intraocular pressure increase when pneumoperitoneum was associated with the head-down position. However, the intraocular pressure increase remained within the diurnal range.

Adjuvants, Anesthesia↗

Effect of intra-operative mechanical ventilation using 50% inspired oxygen on pulmonary oxygenation.

Forty-three ASA Grade I patients scheduled for elective abdominal surgery received at random either 25% or 50% inspired oxygen for intra-operative mechanical ventilation lasting 4-6 h. Pulse oximetry was monitored continuously. Venous admixture was assessed from the PaO2/FIO2 ratio and was measured twice intraoperatively: at the time of incision, and during surgical wound closure. PaO2 was measured 1 h after extubation having breathed room air for 10 min, if tolerated. The patients in the two groups were similar in regard to general characteristics, and had similar operations. Patients given oxygen 50% had operations that lasted longer, which made the trial more sensitive. The inspired oxygen did not affect pulmonary gas exchange either within each group or between groups under the conditions of the study. In no patient did pulse oximetry record an oxygen saturation below 95% intra-operatively.

Abdomen↗