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J T Knape

Publications and source records attributed to J T Knape.

At least 19 recordsLinked to original sources
PubMed2001

[Short preoperative health assessment proposed by the Health Council not useful in clinical practice].

OBJECTIVE: To evaluate the value of the short questionnaire drawn up by the Dutch Health Council for the classification of patients to an ASA class (a 5-point scale according to the American Society of Anesthesiologists, on which the patient's preoperative physical condition can be scored) and to propose an anaesthesia care plan for surgery patients aged between 16 to 40 years old. DESIGN: Observational. METHODS: From June 1999 through to May 2000, all 2090 preoperative patients aged 16 to 40 years at the academic hospital of Utrecht, the Netherlands, were asked to complete the Dutch Health Council's short questionnaire. In addition, the usual extensive preoperative health assessment was carried out on these patients. Of the 379 (18%) who were found by the short questionnaire to be 'healthy', 100 were selected. A panel of 10 anaesthesiologists was asked to preoperatively evaluate these 100 patients twice: once using the short questionnaire and once using the usual extensive health evaluation. The primary outcome was the percentage of patients who could be classified to an ASA class and for whom an anaesthesia care plan could be drawn up. The secondary outcome was the information judged by the anaesthesiologists to be either 'redundant' or 'missing' when drawing up an anaesthesia care plan. RESULTS: Using the short questionnaire, 63% of the patients could not be assigned to an ASA class, compared to 22% with the extensive health evaluation (p < 0.0001). On the basis of the information obtained with the short questionnaire, it was not possible to draw up an anaesthesia care plan for any of the patients, while the extensive health evaluation enabled an anaesthesia care plan to be drawn up for 65% of the patients (95% CI: 62-68%). Using the missing information deemed 'necessary', recommendations were made for the minimum scope of a preoperative health assessment for use in patients aged 16 to 40 years old. CONCLUSION: The short questionnaire as proposed by the Dutch Health Council was not found to be useful in practice.

Adolescent↗
PubMed2001

[Limited effect of Health Council guideline on outpatient preoperative evaluation clinics in the Netherlands: an inventory].

OBJECTIVE: To investigate the current status of preoperative evaluation in the Netherlands and the implementation of the Health Council recommendations. DESIGN: Cross-sectional study. METHOD: All Dutch anaesthesiologic partnerships and their hospital managers in February 2000 received a structured questionnaire about the existence of an outpatient evaluation clinic, possible problems in creating such a clinic and the contents of preoperative evaluation. RESULTS: We received responses of 101 (80%) and 111 (87%) from anaesthesiologists and managers, respectively. From 119 hospitals (94%) we received at least one useful questionnaire. On January 1, 2000, 24 (20%) hospitals had a complete and 36 (30%) a partial outpatient clinic. Within one year, 44% of the hospitals without a preoperative outpatient clinic expected to create one. The most common problem concerned financing this clinic. In hospitals with a complete clinic, anaesthesiologists were more often in employment (odds ratio (OR): 2.5; 95% confidence interval (95% CI): 1.0-10.0) and a routinely performed physical examination by the anaesthesiologist (or under his or her responsibility) was also conducted more often (OR: 5.0; 95% CI: 1.6-15.0). Not every patient saw an anaesthesiologist before entering the operating room in 70% of all hospitals. In hospitals without outpatient clinic, 57% of the day-surgery patients contacted the anaesthesiologist in the operating room. CONCLUSION: The recommendations of the Health Council of the Netherlands with respect to contents and organisation of the preoperative evaluation had, 3 years after being published, limited effect.

Adult↗
PubMed2001

A reduction in type and screen: preoperative prediction of RBC transfusions in surgery procedures with intermediate transfusion risks.

In many patients, a 'type and screen' procedure is routinely performed before surgery. However, most patients are not transfused after all. Can we predict, which surgical patients will and will not be transfused, to reduce the number of these investigations? We studied 1482 consecutive surgical patients with intermediate risk for transfusion. Multivariate logistic regression modelling and the area under the Receiver Operating Characteristic curve (ROC area) were used to quantify how well age, gender, surgical procedure, emergency or elective surgery and anaesthetic technique predicted transfusion, and whether the preoperative haemoglobin concentration had added predictive value. Gender, age > or =70 yr, and type of surgery were independent predictors of transfusion, with a ROC area of 0.75 (95% CI: 0.72-0.79). Validating this model with an easily used prediction rule in a second patient population yielded a ROC area of 0.70 (95% CI: 0.63-0.77). With this rule type and screen could correctly be withheld in 35% of these patients. In the remaining 65% of the patients, a further reduction in type and screen investigations of 15% could be achieved using the preoperative haemoglobin concentration. Using a simple prediction rule, preoperative type and screen investigations in patients who have to undergo surgery procedures with intermediate transfusion risk can be avoided in about 50%. This may reduce patient burden and hospital costs (on average: 3 million US$ per 100 000 procedures).

Adolescent↗
PubMed2001

Activation of interictal spiking in mesiotemporal lobe epilepsy by propofol-induced sleep.

The objective of this study was to test whether low-dose propofol increases the number of interictal spikes in patients with mesiotemporal lobe epilepsy, and to determine whether this is the result of intrinsic properties and is restricted to the primary epileptogenic focus. Controlled infusion of propofol in step-up/-down target concentrations of 0, 0.3, 0.6, and 0.8 mg/L was administered to 10 patients during a 3.5-hour daytime EEG registration. The number of spikes were counted and related to propofol concentration and sleep level. Results were compared with a spontaneous, nocturnal first sleep cycle in 9 of 10 patients. All patients entered nonrapid eye movement 1 sleep during propofol administration, and 8 reached nonrapid eye movement 2 sleep. In 7 patients who showed spikes, spikes were related to sleep (P < 0.05) and not to increasing (P = 0.1) or decreasing (P = 0.5) propofol concentration. Six of nine patients showed more spikes during spontaneous (nocturnal) sleep than during propofol-induced sleep. Contralateral spiking was not suppressed selectively. Low-dose propofol is a safe means of increasing spiking in these patients because it induces sleep. There were no signs of an intrinsic epileptogenicity of propofol or a selective effect on ipsilateral spikes. Controlled sleep induction will increase the yield of interictal spikes during short interictal recordings such as in magnetoencephalography.

Adult↗
PubMed2000

[Preoperative outpatient evaluation of young adults by anesthesiologist: anamnesis and physical examination are satisfactory--short questionnaire of Dutch Public Health Council is not].

The report of the Netherlands Health Council 'Preoperatief onderzoek; een herijking van uitgangspunten' recommends that the health status of patients aged 16-39 years can be investigated preoperatively by the anaesthesiologist using a short questionnaire (6 questions). However, it is not clear whether such an abbreviated preoperative investigation will be informative enough for a safe and balanced anaesthesiologic management. An overview of relevant literature on the subject of preoperative investigation indicates that the preoperative physical status of patients as reflected by the American Society of Anesthesiologists (ASA) classification is a predictor of perioperative complications. Patients can be classified accordingly on the basis of an extended history and physical examination only: any routine additional investigation, such as ECG, chest X-ray or laboratory investigations, seem superfluous. Only blood group, rhesus factor and the presence of irregular antibodies may need to be determined if indicated by the kind of surgery. Currently, however, there is not sufficient evidence to demonstrate that the short questionnaire of the Netherlands Health Council is informative enough.

Adolescent↗
PubMed2000

Heart displacement during off-pump CABG: how well is it tolerated?

BACKGROUND: Heart displacement during off-pump coronary artery bypass grafting (CABG) is necessary to expose the anastomosic sites. We analyzed the hemodynamic changes in relation to the grafted arteries. METHODS: The relationship between surgical exposure and hemodynamic management was assessed in 150 consecutive patients undergoing off-pump CABG utilizing the Octopus Tissue Stabilization System (Medtronic, Minneapolis, MN). RESULTS: Surgical exposure by anterolateral thoracotomy showed no significant hemodynamic changes. Through sternotomy, stroke volume was significantly reduced by dislocation at all target sites: by 6% at the left anterior descending artery (LAD), 25% at the diagonal branch artery (D), 14% at the right coronary artery (RCA), and 21% at the obtuse marginal artery (OM). The application of head-down positioning (LAD, 56%; D, 74%; RCA, 90%; OM, 96%) increased not only surgical exposure but also preload, producing correction of ventricular filling pressures and output. In a minority of cases, dopamine (3 to 5 microg x kg(-1) x min(-1)) was added to maintain baseline hemodynamic values (LAD, 5%; D, 15%; RCA, 7%; OM, 28%). CONCLUSIONS: Revascularization during anterolateral thoracotomy was uneventful. The sternotomy approach with heart displacement induced right heart compression. Mainly fluid redistribution was sufficient to correct cardiac output. Once stabilized, systemic circulation remained unchanged during revascularization.

Aged↗
PubMed2000

The Octopus Study: rationale and design of two randomized trials on medical effectiveness, safety, and cost-effectiveness of bypass surgery on the beating heart.

The Octopus Study consists of two multicenter randomized clinical trials in which coronary artery bypass grafting on the beating heart (off-pump CABG) using the Utrecht Octopus Method is compared to intracoronary stent implantation and conventional CABG. The primary endpoint in the comparison of off-pump CABG versus stent implantation (OctoStent Trial) is medical effectiveness (i.e., absence of reintervention and major adverse cardiac and cerebrovascular events at 1 year after treatment). The primary endpoint in the comparison of off-pump CABG versus conventional CABG (OctoPump Trial) is cerebral safety (i.e., absence of cognitive deficits and cerebrovascular events at 3 months after treatment). Secondary endpoints in both trials include presence and severity of angina, quality of life, exercise capacity, and cost-effectiveness. A total of 560 patients will be enrolled. A random sample of 210 patients will undergo repeat angiography at 1 year to assess angiographic restenosis rate and graft patency. Including 1-year follow-up, the study will last for 3 years. Control Clin Trials 2000;21:595-609

Angioplasty, Balloon, Coronary↗
PubMed1999

[Guideline for administration of sedatives and analgesics by physicians who are not anesthesiologists. National Organization for Quality Assurance in Hospitals].

A consensus text for sedation or analgesia in diagnostic or therapeutic procedures has been developed for application by non-anaesthetist physicians. The final consensus text has the support of 17 scientific societies in the Netherlands. There is not enough medical manpower for direct, personal, specialist-based supervision of level 3 sedation procedures (the patient is relaxed, with eyes closed, but promptly reacts to verbal commands) for significant number of patients in the Netherlands. Sedation and analgesia may be administered by other health care personnel than anaesthesiologists when a number of conditions are met. These concern risk management, information to the patient, patient's consent, requirements for medical and supporting personnel, equipment, sedation procedures, monitoring, data management, recovery and aftercare. The consensus party favours titrated administration of small doses of short acting sedative or analgetic drugs. Combining sedative and analgesic drugs increases risk. Sedation and analgesia in children and patients with mental handicaps is acceptable in terms of quality, but requires special expertise, because of the greater psychic and physical vulnerability of these categories of patients.

Adult↗
PubMed1999

Embracing the heart: perioperative management of patients undergoing off-pump coronary artery bypass grafting using the octopus tissue stabilizer.

OBJECTIVE: To describe hemodynamic alterations during coronary artery bypass grafting (CABG) without extracorporeal circulation using the Octopus Tissue Stabilizer, and to describe the two anesthetic management protocols based on either general anesthesia with opioids (34 patients) or general anesthesia with high thoracic epidural anesthesia (TEA; 66 patients). DESIGN: A prospective observational report. SETTING: An academic university heart center. PARTICIPANTS: First 100 patients undergoing CABG using the Octopus Tissue Stabilizer. INTERVENTIONS: None. MAIN RESULTS: Current management provided satisfactory results in preventing hypoperfusion of the heart and inadequate systemic circulation without the use of major pharmacologic interventions. Movement of the heart to reach the target site of anastomosis caused hemodynamic alterations. These could easily be corrected by anesthetic interventions, such as fluid load and low doses of inotropes. High TEA allows earlier extubation compared with the opioid anesthesia technique (0.9 v 4.5 hours). Perioperative management and the incidence of postoperative complications did not differ between anesthetic techniques. Major complications, such as death, intraoperative myocardial infarction, and stroke, did not occur. CONCLUSION: Both anesthetic protocols are safe and effective in handling these patients. Off-pump CABG surgery requires anesthetic interventions because hemodynamic alterations are caused by the presentation of the heart to the surgeon. The complication rate is low but needs to be evaluated, compared with conventional CABG, in a prospective randomized study. High thoracic epidural anesthesia allows early recovery, but improved outcome could not be proved in this patient group.

Adjuvants, Anesthesia↗
PubMed1998

[2nd revision consensus on blood transfusion. Central Guidance Organization for Peer Review].

Since 1982 several consensus conferences regarding the transfusion practice in hospitals have been organized in the Netherlands. Repeated updating of the consensus text such as described in this article is required to keep abreast of new developments and changes in clinical practice. Guidelines concerning compatibility testing (the result of compatibility testing is valid for three days at most), the organization of responsibilities and the clinical use of red cell concentrates, including a protocol for transfusion in patients with massive bleeding, were changed. No consensus was reached concerning the need to use only red cells that are antigen c, E and K compatible in women younger than 45 years of age and in patients with abnormal erythropoiesis. Although the need of systematic reviews to support guidelines was recognized, literature reviews revealed that only few studies were designed well enough to allow definitive conclusions regarding the benefits and risks of red cell transfusion.

Adult↗
PubMed1997

The anaesthetist as determinant factor of quality of surgical antimicrobial prophylaxis. A survey in a university hospital.

In actual surgical antimicrobial prophylaxis, the anaesthetist administers the drugs at induction of anaesthesia. In the first phase of our quality-of-use intervention study on antimicrobial drugs in a large university hospital, information on the practice of antimicrobial prophylaxis was needed. The staff of 44 anaesthetists was interviewed by means of a questionnaire. Response rate was 36/44 (82%). The anaesthetists' method of administering surgical prophylaxis was rather uniform and inexpensive: cephalosporins were almost exclusively administered by bolus method. The main reason was that infusion was more cumbersome (range 77-85%). Communication between surgeon and anaesthetist was reported to be poor, and in two out of three operating departments, orders of prophylaxis transmitted at or after induction accounted for more than 80%. Seventy-seven percent of the responders asked the surgeon if prophylaxis was necessary if they were in doubt; 20% responded that they checked it systematically. The data collected by the inquiry proved useful in the process of optimizing surgical prophylaxis in our hospital.

Adult↗
PubMed1997

A randomized, blind comparison of remifentanil and alfentanil during anesthesia for outpatient surgery.

UNLABELLED: We compared remifentanil, an esterase-metabolized opioid, with alfentanil as part of balanced anesthesia with at least 0.8% isoflurane during outpatient surgery in a randomized, double-blind trial. One hundred two patients received remifentanil, and 99 patients received alfentanil. Patients who received remifentanil experienced significantly fewer stress responses to surgical stimuli (52.9% and 65.7%, P < 0.05); significantly fewer remifentanil patients responded to skin closure (11% and 22%, P < 0.05) than patients who received alfentanil. Significantly more patients in the alfentanil group required extra analgesia compared with the remifentanil group (P < 0.05). Time to respond to verbal command was shorter for alfentanil than remifentanil (median 7 min vs 9 min), and times to spontaneous respiration (median 5 min vs 8 min), adequate respiratory rate (median 6 min vs 9 min), and tracheal extubation (median 6 min vs 9 min) were significantly shorter for alfentanil in comparison with remifentanil (P < 0.05). Remifentanil patients, however, showed significantly better recovery of psychomotor and psychometric function between 30 and 90 min after surgery (P < 0.05). The incidences of hypotension intraoperatively and shivering postoperatively were significantly higher with remifentanil. No unexpected or serious adverse events were recorded with remifentanil; however, one patient who received alfentanil experienced severe recurrent respiratory depression after surgery. The metabolic profile of remifentanil allowed better intraoperative analgesia without compromising recovery. IMPLICATIONS: The pharmacological profile of remifentanil, a new opioid for use in anesthesia, suggests that rapid recovery will occur after its use. This study of 200 outpatients shows that the differences suggested from kinetic studies are not always borne out in clinical practice, although later recovery variables did, in fact, favor remifentanil.

Adolescent↗
PubMed1996

Optimizing the timing of antimicrobial prophylaxis in surgery: an intervention study.

The timing of surgical antimicrobial prophylaxis was determined before and after an intervention programme of education of surgeons, anaesthetists and nurses on the subject of antimicrobial drug prophylaxis, and the subsequent implementation of new protocols of single dose prophylaxis administered within one hour before incision. This prospective study was performed in three surgical departments of a university hospital. For comparison, the timing of prophylaxis was also determined in an operating department of a community hospital. The timing improved considerably in the departments of the university hospital where the intervention was carried out: administration of the first dose within one hour before incision increased from 39% to 69% in department A and from 64% to 80% in department B. Before the intervention, seven out of 16 prophylactic doses were given after inflation of the tourniquet. After the intervention all doses of prophylactic antibiotics were administered before inflation of the tourniquet. Initially, the intervals of multidose prophylaxis varied widely. In the second review, single-dose prophylaxis increased from 21% to 78% in department A and from 31% to 85% in department B. We conclude that the intervention succeeded in improving the quality of surgical prophylaxis.

Anti-Bacterial Agents↗
PubMed1995

Accidental hypothermia: incidence, risk factors and clinical course of patients admitted to hospital.

This study was initiated to identify the incidence, risk factors and outcome predictors of patients admitted to hospital in the Netherlands because of accidental hypothermia. Information about these patients was available for study through the National Health Care Data Bank. Between 1987 and 1990, 612 accidental hypothermic patients were admitted: 185 hypothermic patients also suffered from submersion (HYPSUBS), but this was not the case in the remaining 427 patients (HYPNOTSUBS). Patients in the HYPNOTSUBS group were older (average age 55.2 years versus 38.9 years; p < 0.001), remained longer in hospital (average 20.8 days versus 9.2 days; p < 0.001) and had a higher death rate than those in the HYPSUBS group (16.9% versus 5.9%; p < 0.001). In HYPNOTSUBS, increasing age correlated with increases in the length of hospital stay and death rate. This relationship was not found in HYPSUBS. Trauma was the major associated problem in both groups; these patients had the highest death rate (22.8% versus 16.7%; not significant). Death occurred within 2 days in 54% of HYPNOTSUBS non-survivors and 73% of HYPSUB non-survivors. HYPNOTSUBS admitted to university hospitals showed a lower death rate (5.9%) compared with HYPNOTSUBS admitted to non-university hospitals with less than 400 beds (13.4%) or more than 400 beds (21.7%). In contrast, the death rate in HYPSUB was higher in university hospitals (14.3%) than in non-university hospitals with less than 400 beds (5.2%) or more than 400 beds (3.6%). We observed that the incidence of accidental hypothermia is low at 1.1 per 100,000 inhabitants per year. We concluded that HYPNOTSUBS and HYPSUB are different groups of patients with respect to demographic data, risk factors and prognostic factors. Old age is an important unfavourable prognostic factor in HYPNOTSUB but not in HYPSUB. Hypothermia with trauma is an unfavourable combination in both groups. Almost half of the HYPNOTSUBS non-survivors died after more than 2 days. Because body temperature will have returned to normal by then, this must be the result of late complications. Most HYPSUB non-survivors died during the first 2 days, probably as a direct result of the submersion injury.

Accidents↗
PubMed1994

Resuscitation skills of lay public after recent training.

STUDY OBJECTIVE: To investigate the ability of laypeople to apply basic CPR techniques after recent training. DESIGN: Cross-sectional assessment of practical CPR skills. TYPE OF PARTICIPANTS: 151 laypeople who were trained twice in the preceding 20 to 24 months. MEASUREMENTS AND MAIN RESULTS: Practical skills were tested using six primary recorded variables that describe the quality of CPR techniques in a training situation. A total score on the skills of each participant was computed on the basis of a predefined scoring system. Thirty-three percent of the participants were able to perform adequate CPR. The compression:relaxation ratio, the breathing volume, and the breathing interval were points of concern. CONCLUSION: Practical skills in basic CPR after a 12-month training interval, though better in this study than in many previous studies, are insufficient in the majority of laypeople. The results of this study could be used to design a better tailored (re)instruction program, with an emphasis on regular, frequent refresher courses.

Adolescent↗
PubMed1994

Importance of the coronary collateral circulation for the distribution of anterograde and retrograde delivered cardioplegic solution in aortocoronary bypass surgery: a haemodynamic study.

The importance of coronary collateral circulation for homogeneous distribution of anterograde and retrograde delivery of cardioplegia was evaluated in 36 patients undergoing myocardial revascularization. All patients had three-vessel coronary artery disease, with a stenosis of the right coronary artery of at least 80%. The patients were randomized into two groups: group A (n = 19) received anterograde delivered cardioplegic solution and group B (n = 17) received retrograde. Both groups were further subdivided depending on the pathology of the right coronary artery, as evaluated on preoperative coronary angiography. In group A1 (n = 8) and group B1 (n = 7) there was no visualization of collateral circulation from the left to the right coronary artery system, whereas in group A2 (n = 11) and group B2 (n = 10) there was retrograde filling of the right coronary artery by collateral circulation. Right atrial pressure increased significantly (P < 0.05) in group A1 and was elevated in group A2, but not significantly (P = 0.07). By contrast, right arterial pressure decreased in groups B1 and B2. Analysis of the individual differences in the right atrial filling pressure showed a statistical significance between the two subgroups (group B1-1.0(0.5) versus group B2-1.8(1.1), P < 0.05), although the individual decrease of the right ventricular stroke work index was not significant. It is concluded that collateral circulation is important for an adequate distribution of anterogradely delivered cardioplegia and is also beneficial in cases of retrograde delivery.

Adult↗