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J J de Lange

Publications and source records attributed to J J de Lange.

At least 19 recordsLinked to original sources
PubMed2006

Compound A and carbon monoxide production from sevoflurane and seven different types of carbon dioxide absorbent in a patient model.

BACKGROUND: The degradation of sevoflurane can lead to the production of compound A (CA) and carbon monoxide (CO) and an increase in temperature of the absorbent. CA is known to be nephrotoxic in rats. These reactions depend on the strong base and water contents of the carbon dioxide absorbent used. The purpose of this study was to measure the maximum amounts of CA and CO produced, and the temperature increase, for seven different carbon dioxide absorbents for sevoflurane containing different contents of strong bases. METHODS: Seven absorbents [some free of strong bases (f)] were employed in hydrated (h) and completely desiccated (d) conditions in a patient model, using a circle anesthesia system connected to an artificial lung. Low-flow anesthesia with an oxygen-nitrous oxide mixture was maintained using 0.8% sevoflurane. For the quantification of CA and CO, a portable gas chromatograph was used. The temperature was measured inside the absorbent. RESULTS: In consecutive order of CA-producing potency, Amsorb(f)(d), Drägersorb(h), Medisorb(h), lithium hydroxide(f)(d), Drägersorb(d), Medisorb(d), Spherasorb(h) and Spherasorb(d) produced small amounts of CA. Loflosorb and Superia, which are free of strong bases, did not produce any CA or CO in hydrated or desiccated conditions. Only desiccated Drägersorb, Medisorb and Spherasorb demonstrated small amounts of CO accompanied by a significant temperature increase. CONCLUSION: In this patient model, we demonstrated that different types of absorbent produced small amounts of CA and CO or none at all. No relationship could be established between temperature and CA concentration.

Absorption↗
PubMed2006

The mechanism of sevoflurane-induced cardioprotection is independent of the applied ischaemic stimulus in rat trabeculae.

BACKGROUND: Sevoflurane protects the myocardium against ischaemic injury through protein kinase C (PKC) activation, mitochondrial K+ATP-channel (mitoK+ATP) opening and production of reactive oxygen species (ROS). However, it is unclear whether the type of ischaemia determines the involvement of these signalling molecules. We therefore investigated whether hypoxia (HYP) or metabolic inhibition (MI), which differentially inhibit the mitochondrial electron transport chain (ETC), are comparable concerning the relative contribution of PKC, mitoK+ATP and ROS in sevoflurane-induced cardioprotection. METHODS: Rat right ventricular trabeculae were isolated and isometric contractile force (Fdev) was measured. Trabeculae were subjected to HYP (hypoxic glucose-free buffer; 40 min) or MI (glucose-free buffer, 2 mM cyanide; 30 min), followed by 60 min recovery (60 min). Contractile recovery (Fdev,rec) was determined at the end of the recovery period and expressed as a percentage of Fdev before hypoxia or MI, respectively. Chelerythrine (CHEL; 6 microM), 5-hydroxydecanoic acid sodium (100 microM) and n-(2-mercaptopropionyl)-glycine (MGP; 300 microM) were used to inhibit PKC, mitoK+ATP and ROS, respectively. RESULTS: Fdev,rec after HYP was reduced to 47 (3)% (P<0.001 vs control; n=5) whereas MI reduced Fdev,rec to 28 (5)% (P<0.001 vs control; n=5). A 15 min period of preconditioning with sevoflurane (3.8%) equally increased contractile recovery after HYP [76 (9)%; P<0.05 vs HYP] and MI [67 (8)%; P<0.01 vs MI]. Chelerythrine, 5-hydroxydecanoate and n-(2-mercaptopropionyl)-glycine abolished the protective effect of sevoflurane in both ischaemic models. Trabeculae subjected to HYP or MI did not demonstrate any increased apoptotic or necrotic markers. CONCLUSIONS: PKC, mitoK+ATP and ROS are involved in sevoflurane-induced cardioprotection after HYP or MI, suggesting that the means of mitochondrial ETC inhibition does not determine the signal transduction pathway for cardioprotection by anaesthetics.

Anesthetics, Inhalation↗
PubMed2005

Predictive value of symptom level measurements for complex regional pain syndrome type I.

The validity with respect to presence or absence of CRPS I according to Veldman's criteria was assessed for measured pain, temperature, volume differences and limitations in range of motion. Evaluated were 155 assessments of 66 outpatients, initially diagnosed with CRPS I, but many of them not so on follow up visits. Pain was measured with VAS and McGill, temperature by infrared thermometry, volume differences by water displacement volumeters and limitations in range of motion by universal goniometers. Sensitivity, specificity, positive and negative predictive value of the measurement instruments at different cut-off points was calculated. Combined symptom scores were evaluated in a similar fashion. High sensitivity was found for the VAS, McGill, and range of motion. The specificity was overall lower, but highest values were obtained for volume differences. The positive predictive value was good for all measurement instruments. Negative predictive value was lower, especially for measurement of temperature and volume asymmetries. If sensitivity and specificity are equally important, VAS>3 cm, McGill>6 words, temperature difference>or=0.4 degrees C, volume difference>6.5% and ROM limitation>15% provide the best results. Using these cut off values, the highest value of sensitivity and of sensitivity and specificity combined, was found for a combination of VAS, McGill and ROM. The highest value of specificity was found for different combinations of 3, 4 and 5 instruments, all containing the VAS. We conclude that the measured pain, temperature, volume and range of motion can be used as diagnostic indicators for establishing presence or absence of CRPS I.

Adult↗
PubMed2005

Postoperative condition after the use of remifentanil with a small dose of piritramide compared with a fentanyl-based protocol in patients undergoing craniotomy.

BACKGROUND AND OBJECTIVE: The use of remifentanil requires other analgesics for postoperative pain relief compared to fentanyl in patients undergoing craniotomy. This could possibly reduce the postoperative advantages of this short-acting opioid. METHODS: We compared remifentanil and fentanyl-based anaesthesia in a randomized observer and patient blinded trial on patients, undergoing an elective craniotomy. Twenty patients received anaesthesia using remifentanil with a small dose of piritramide (0.1 mg kg(-1)) after closure of the dura mater. Twenty patients underwent a fentanyl-based protocol. In both groups, anaesthesia was induced with thiopental and rocuronium, and maintained with 0.6-1 minimum alveolar concentration (MAC) isoflurane in a nitrous oxide/oxygen mixture 2:1 and rocuronium. Patients received 1 g of paracetamol rectally postoperatively. A visual analogue scale (VAS) for pain, the Glasgow Coma Score, a modified Aldrete Score, arterial carbon dioxide tension (PaCO2) and piritramide consumption were evaluated every half an hour postoperatively. RESULTS: No significant differences were found for pain, Aldrete or Glasgow Coma scores or for PaCO2 between the groups when controlled for age, although the pain and Glasgow Coma Scores were consistently higher and PaCO2 lower in the remifentanil group. Furthermore, 11 out of 20 patients in the remifentanil group requested extra piritramide as opposed to 7 out of 20 in the fentanyl group (P = 0.11). CONCLUSIONS: Despite the intraoperative use of piritramide in the remifentanil group, patients experienced more pain postoperatively. A significant influence of age on pain intensity was found. The use of remifentanil with a small dose of piritramide of 0.1 mg kg(-1) has no evident advantage over the use of fentanyl considering the postoperative conditions after craniotomy.

Adolescent↗
PubMed2005

Carbon monoxide production from desflurane and six types of carbon dioxide absorbents in a patient model.

BACKGROUND: Desflurane is known to produce high concentrations of carbon monoxide (CO) in desiccated sodalime or Baralyme (Allied Healthcare Products, St. Louis, MO). Desiccated absorbents without strong bases like potassium hydroxide or sodium hydroxide are reported to produce less or no CO at all. The purpose of this study is to compare the concentration of CO in an anesthesia circuit for desflurane with six different types of completely desiccated CO(2) absorbents with less strong bases than sodalime. METHODS: A patient model was simulated using a circle anesthesia system connected to an artificial lung. Completely desiccated CO(2) absorbent (950 g) was used in this system. A low flow anesthesia (500 ml min(-1)) was maintained using desflurane. For immediate quantification of CO production a portable gas chromatograph was used. RESULTS: Peak concentrations of CO were very high in Medisorb (Datex-Ohmeda, Hoevelaken, The Netherlands) and Spherasorb (Intersurgical, Uden, The Netherlands) (13317 and 9045 p.p.m., respectively). It was lower with Loflosorb (Intersurgical, Uden, The Netherlands) and Superia (Datex-Ohmeda, Hoevelaken, The Netherlands) (524 and 31 p.p.m., respectively). Amsorb (Armstrong, Coleraine, N. Ireland) and lithium hydroxide produced no CO at all. CONCLUSION: Medisorb and Spherasorb are capable of producing large concentrations of CO when desiccated. Loflosorb and Superia produce far less CO under the same conditions. Amsorb and lithium hydroxide should be considered safe when desiccated.

Absorption↗
PubMed2003

The treatment of complex regional pain syndrome type I with free radical scavengers: a randomized controlled study.

To compare the effects of two free radical scavengers, dimethylsulfoxide 50% (DMSO) and N-acetylcysteine (NAC), for treatment of complex regional pain syndrome I (CRPS I), a randomized, double-dummy controlled, double-blind trial was conducted. Two outpatient clinics of two university hospitals in The Netherlands participated in the study and 146 patients, were included over a period of 24 months. Patients were randomized into two treatment groups, one was instructed to apply DMSO 50% five times daily to the affected extremity, the second was treated with NAC 600mg effervescent tablets three times daily, both combined with placebo. Interventions were accompanied by pain medication, occupational therapy for upper extremity CRPS I and physical therapy for lower extremity CRPS I in specific circumstances. Treatment was given for 17 weeks, with a possibility to continue or switch medication after this period, up to 1 year following the onset of treatment. An impairment level sum score was the primary outcome measure. Upper and lower extremity skills and functions, and general health status were also evaluated. Overall, no significant differences were found between NAC and DMSO after 17 and 52 weeks on impairment level and general health status. Significant differences were found for subscores of lower extremity function, in favor of DMSO-treatment. Subgroup analysis showed more favorable results for DMSO for warm CRPS I and significantly better performance of NAC for patients with a cold CRPS I. Results tended to be negatively influenced if the duration of the complaint was longer. Treatment with DMSO and NAC are generally equally effective in treatment of CRPS I. Strong indications exist for differences in effects for subgroups of patients with warm or cold CRPS I: for warm CRPS I, DMSO-treatment appears more favorable, while for cold CRPS I, NAC-treatment appears to be more effective.

Acetylcysteine↗
PubMed2002

Interrater reliability of diagnosing complex regional pain syndrome type I.

BACKGROUND: Diagnosis of complex regional pain syndrome type I (CRPS I) is based on clinical observation of symptoms. As little information is available on the reliability of CRPS I diagnosis, we evaluated the agreement between therapists with regard to the presence and severity of CRPS I and its symptoms. METHODS: The interrater reliability was evaluated in 37 presumed CRPS I patients by three observers; one consultant anesthesiologist and two resident anesthesiologists. Patients were assessed on the basis of Veldman's CRPS criteria. RESULTS: The interrater reliability for diagnosing CRPS I was good for the majority of observer combinations. The percentage of agreement for the absence or presence of CRPS I was good (88%-100%). Cohen's Kappa's ranged from 0.60 to 0.86. The agreement for the mean symptom score ranged from 70.2% to 88.6%; Kappa's were lower and showed more variation. Interrater reliability for assessment of the severity of CRPS I and its symptoms was poor. Factors influencing the interrater reliability were symptom type, individual observers and sample population. CONCLUSION: Diagnosing CRPS I can be performed on the basis of clinical observation. Further assessment of severity of CRPS I and its symptoms should be performed with reliable and valid measurement instruments.

Adult↗
PubMed2002

Dexamethasone decreases the pro- to anti-inflammatory cytokine ratio during cardiac surgery.

BACKGROUND: Cytokines regulate inflammation associated with cardiopulmonary bypass (CPB). Pro-inflammatory cytokines may cause myocardial dysfunction and haemodynamic instability after CPB, but the release of anti-inflammatory cytokines is potentially protective. We studied the effects of dexamethasone on pro- and anti-inflammatory cytokine responses during coronary artery bypass grafting surgery. METHODS: Seventeen patients were studied: nine patients received dexamethasone 100 mg before induction of anaesthesia (group 1) and eight patients acted as controls (group 2). Plasma levels of tumour necrosis factor (TNF)-alpha, interleukin (IL)-6, IL-8, IL-10 and IL-4 were measured perioperatively. RESULTS: TNF-alpha and IL-8 did not increase significantly in group 1 whereas they increased in group 2 to greater than preoperative values (P<0.05). IL-6 increased in both groups, with lower values in group 1 than in group 2 (P<0.05). IL-10 increased in both groups, with higher values in group 1 (P<0.05). IL-4 did not change in group 1 but decreased in group 2 compared with pre-induction values (P<0.05). After surgery, patients in group 2 had tachycardia, hyperthermia, a greater respiratory rate and higher pulmonary artery pressure, and a longer stay in the intensive care unit. CONCLUSION: Dexamethasone given before cardiac surgery changes circulating cytokines in an anti-inflammatory direction. Postoperative outcome may be improved by inhibition of the systemic inflammatory response.

Aged↗
PubMed2001

[Preoperative examination: anamnesis and physical examination mandatory].

Preoperative assessment has been subject to discussion for many years. What should be done and by whom? Fortunately there is a general consensus that routine laboratory and function tests are not only of no benefit to the patient but are also wasteful of resources. The Preoperative Assessment Commission of the Dutch Ministry of Health, Welfare and Sport, supports the initiative for preoperative assessment clinics run by anaesthesiologists. Yet in their advice, this Commission has proposed screening by means of an abridged questionnaire. Efforts to validate this questionnaire have demonstrated that in practice it was not helpful. Therefore it seems justified to conclude that preoperative screening should not fundamentally differ from that performed during a basic clinical examination.

Anesthesiology↗
PubMed2001

Treatment of reflex sympathetic dystrophy (CRPS type 1): a research synthesis of 21 randomized clinical trials.

A blinded meta analysis was performed on randomized clinical trials (RCT) on the medicinal treatment of reflex sympathetic dystrophy (complex regional pain syndrome type I) to assess the methodological quality and quantify the analgesic effect of treatments by calculating individual and summary effect sizes. The internal validity of 21 RCTs was investigated and the quality weighted summary effect size was calculated using a fixed effect model (Glass Delta). The methodological quality ranged from moderate to good (average 46%). Differences were found between the trials in inclusion/exclusion criteria, treatment methods, duration of treatments and trials, and measurement instruments. Statistical analysis was possible for four subgroups; one evaluating the analgesic effects of sympathetic suppressors in general (n = 12), one subgroup concerning the analgesic effects of guanethidine (n = 6), one investigating the analgesic effect of intravenous regional sympathetic blocks (n = 9), and one subgroup (n = 5) evaluating the analgesic effect of calcitonin. Except for the calcitonin subgroup (P = 0.002), the quality-weighted summary effect size of these subgroups were not significant. No significant analgesic effect by sympathetic suppressing agents could be established. Calcitonin seems to provide effective pain relief in reflex sympathetic dystrophy patients. The results of the present study show that weighting methodological quality influences the magnitude of the effect sizes of specific treatment methods. Future studies should control for methodological quality.

Analgesics↗
PubMed2001

Increasing the efficacy of a celiac plexus block in patients with severe pancreatic cancer pain.

The purpose of this study was to evaluate the technical possibilities of placing a catheter near the celiac plexus for performance of a celiac plexus block, and to study the efficacy of repeated neurolytic celiac plexus blocks with alcohol in patients with advanced pancreatic cancer pain resistant to opioid treatment. In 12 patients, a neurolytic celiac plexus block with alcohol, administered via an indwelling celiac catheter, was performed. To evaluate the efficacy, visual analog scale scores were recorded every day. Quality of life scores were registered before and 4 weeks following the procedure. Alterations in opioid consumption, and the time between the diagnosis of pancreatic cancer and the performance of the block, were registered. All patients were followed until they died. Two patients remained without pain after the first neurolytic celiac plexus block. In all other patients a second block was administered which provided only temporary relief. Additional intermittent administration of bupivacaine through the catheter was necessary to provide adequate pain relief in these patients. Quality of life increased significantly during the treatment. Opioid consumption decreased significantly in all patients. Our study indicates that a neurolytic celiac plexus blockade with alcohol results in a significant but short-lasting analgesic effect. The use of a celiac catheter improves the long-term management of pancreatic cancer pain.

Autonomic Nerve Block↗
PubMed2001

The differential effect of propofol on contractility of isolated myocardial trabeculae of rat and guinea-pig.

1. The effects of propofol on myocardial contractility were studied in rat, in which the contractile activation mainly depends on calcium derived from the sarcoplasmic reticulum (SR), and guinea-pig, in which transsarcolemmal influx of calcium plays a major role. 2. Intact and chemically skinned trabeculae from the right ventricle were studied. Intact trabeculae were electrically stimulated and force development during steady state and post rest contractions was measured. In saponin skinned trabeculae Ca(2+) uptake and release by the SR was studied. In Triton skinned trabeculae the influence of propofol on calcium sensitivity of the myofilaments was studied. 3. In intact rat trabeculae propofol in concentrations of 28, 112 and 280 microM did not change peak force development nor the pattern of post rest contraction. In guinea-pig trabeculae propofol significantly reduced peak force to respectively 64, 40 and 23% of control values and the post rest contractions were potentiated. In skinned trabeculae propofol did not affect Ca(2+) handling by the SR, nor did it change force production and Ca(2+) sensitivity of the myofilaments. 4. This study shows that, in contrast to rat, in guinea-pig propofol directly depresses myocardial contractility, probably by decreasing transsarcolemmal Ca(2+) influx. There is no significant influence of propofol on Ca(2+) handling by the SR, nor on the contractile proteins.

Anesthetics, Intravenous↗
PubMed2001

Mortality associated with anaesthesia: a qualitative analysis to identify risk factors.

From a prospectively defined cohort of patients who underwent either general, regional or combined anaesthesia from 1 January 1995 to 1 January 1997 (n = 869 483), all consecutive patients (n = 811) who died within 24 h or remained unintentionally comatose 24 h after anaesthesia were classified to determine a relationship with anaesthesia. These deaths (n = 119; 15%) were further analysed to identify contributing aspects of the anaesthetic management, other factors and the appropriateness of care. The incidence of 24-h peri-operative death per 10 000 anaesthetics was 8.8 (95% CI 8.2-9.5), of peri-operative coma was 0.5 (0.3-0.6) and of anaesthesia-related death 1.4 (1.1-1.6). Of the 119 anaesthesia-related deaths, 62 (52%) were associated with cardiovascular management, 57 (48%) with other anaesthetic management, 12 (10%) with ventilatory management and 12 (10%) with patient monitoring. Inadequate preparation of the patient contributed to 30 (25%) of the anaesthesia-related deaths. During induction of anaesthesia, choice of anaesthetic technique (n = 18 (15%)) and performance of the anaesthesiologist (n = 8 (7%)) were most commonly associated with death. During maintenance, the most common factors were cardiovascular management (n = 43 (36%)), ventilatory management (n = 12 (10%)) and patient monitoring (n = 12 (10%)). In both the recovery and the postoperative phases, patient monitoring was the most common factor (n = 12 (10%) for both). For cardiovascular, ventilatory and other anaesthetic management, human failure contributed to 89 (75%) deaths and organisational factors to 12 (10%). For inadequate patient monitoring, human factors contributed to 71 (60%) deaths and organisational factors to 48 (40%). Other contributing factors were inadequate communication (30 deaths (25%) for all four aspects of the anaesthetic management) and lack of supervision (particularly for ventilatory management). Inadequate care was delivered in 19 (16%) of the anaesthesia-related deaths with respect to cardiovascular management, in 20 (17%) with respect to ventilatory management, in 18 (15%) with respect to patient monitoring and in 23 (19%) with respect to other anaesthetic management.

Anesthesia↗
PubMed2001

Liver and renal function after volatile induction and maintenance of anesthesia (VIMA) with sevoflurane versus TIVA with sufentanil-midazolam for CABG surgery.

We compared liver and renal function after volatile induction and maintenance of anesthesia (VIMA) with sevoflurane and minimal dose sufentanil versus total intravenous anesthesia (TIVA) with moderate dose of midazolam and sufentanil in patients undergoing CABG surgery. Eighty nine patients were studied retrospectively after VIMA (44 patients) or after TIVA (45 patients). Liver and renal function were measured before (T0), then 1 (T1), 2 (T2), 5 (T3) days and 6 weeks (T4) after the operation. Serum levels of aspartate aminotransferase (ASAT) and lactate dehydrogenase (LDH) increased in both groups at T1, T2 and T3 and the highest levels were at T1. Levels of total bilirubin (TBil) increased at T1 only in the TIVA group. Levels of g-glutamyl transpeptidase (GGT) and alanine aminotransferase (ALAT), increased in both groups at T3. Serum levels of creatinine (Cr) were high in both groups on T1 and T2. Blood urea nitrogen (BUN) was high in both group at T2, and T3 with the peak levels in T2. Six weeks after the operation all liver and renal functions were normal in both groups. We concluded that VIMA with sevoflurane during cardiac surgery has no untoward effects on liver or renal functions. The transient reversible elevation was comparable in the VIMA and TIVA groups which was most probably due to the effect of the operation itself.

Aged↗
PubMed2000

[Do medical schools still train doctors?].

In practice, medical finals are not final and a supplementary training is necessary before medicine may be practised independently. Social factors and an ongoing evolution of medical science prompt reconsideration of the structure, content and duration of the training of doctors and specialists. This was the subject of a meeting of this Journal. One possibility of differentiation in the basic training is an early subdivision into care physicians, clinical specialists and health physicians. In the training of social medical officers one of the factors to be taken into account is the influence of principals. For GP's, postgraduate training is increasingly important because of social and other developments. The training of non-surgical specialists can be made shorter since a significant proportion of the time in the present training is devoted to areas requiring special attention. The training of surgical specialists could be shortened by introducing a training programme that is independent of the procedure. Responsibility for the total care of the patient will be borne by the specialists jointly.

Education, Continuing↗
PubMed2000

Continuous brachial plexus block as treatment for the Pancoast syndrome.

BACKGROUND: Six patients with severe neuropathic pain caused by a Pancoast tumor were treated with the continuous administration of local anesthetics. These patients had not responded to any other treatment, including nonsteroidal anti-inflammatory drugs, opioids, dexamethasone, tricyclic antidepressants, anticonvulsants, ketamine, and transcutaneous electric nerve stimulation. INTERVENTIONS: An axillary catheter was placed in the brachial plexus using a posterior approach that has not been described previously. A continuous infusion system of local anesthetics was delivered via a catheter. In two patients, the main purpose was to evaluate the technical possibilities and implications of this new approach. In all patients, the visual analogue scale score was evaluated until the patient died. In four additional patients, the quality of life and performance skills were recorded. RESULTS: In all patients, there was a significant reduction in the visual analog scale score, and there was an increase in performance skills and quality of life in four patients. No side effects occurred from this technique or from the continuous administration of local anesthetics. CONCLUSIONS: We conclude that neuropathic pain may be treated by local anesthetics administered through an axillary catheter placed in the brachial plexus. This technique is reversible and is preferable to destructive procedures such as cordotomy.

Aged↗