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Kees H Polderman

Publications and source records attributed to Kees H Polderman.

36 records · Page 2Linked to original sources
PubMed2004

Application of therapeutic hypothermia in the intensive care unit. Opportunities and pitfalls of a promising treatment modality--Part 2: Practical aspects and side effects.

Induced hypothermia can be used to protect the brain from post-ischemic and traumatic neurological injury. Potential clinical applications and the available evidence are discussed in a separate paper. This review focuses on the practical aspects of cooling and physiological changes induced by hypothermia, as well as the potential side effects that may develop. These side effects can be serious and, if not properly dealt with, may negate some or all of hypothermia's potential benefits. However, many of these side effects can be prevented or modified by high-quality intensive care treatment, which should include careful monitoring of fluid balance, tight control of metabolic aspects such as glucose and electrolyte levels, prevention of infectious complications and various other interventions. The speed and duration of cooling and rate of re-warming are key factors in determining whether hypothermia will be effective; however, the risk of side effects also increases with longer duration. Realizing hypothermia's full therapeutic potential will therefore require meticulous attention to the prevention and/or early treatment of side effects, as well as a basic knowledge and understanding of the underlying physiological and pathophysiological mechanisms. These and other, related issues are dealt with in this review.

Animals↗
PubMed2004

Application of therapeutic hypothermia in the ICU: opportunities and pitfalls of a promising treatment modality. Part 1: Indications and evidence.

OBJECTIVE: Hypothermia has been used for medicinal purposes since ancient times. This paper reviews the current potential clinical applications for mild hypothermia (32-35 degrees C). DESIGN AND SETTING: Induced hypothermia is used mostly to prevent or attenuate neurological injury, and has been used to provide neuroprotection in traumatic brain injury, cardiopulmonary resuscitation, stroke, and various other disorders. The evidence for each of these applications is discussed, and the mechanisms underlying potential neuroprotective effects are reviewed. Some of this evidence comes from animal models, and a brief overview of these models and their limitations is included in this review. RESULTS: The duration of cooling and speed of re-warming appear to be key factors in determining whether hypothermia will be effective in preventing or mitigating neurological injury. Some other potential usages of hypothermia, such as its use in the peri-operative setting and its application to mitigate cardiac injury following ischemia and reperfusion, are also discussed. CONCLUSIONS: Although induced hypothermia appears to be a highly promising treatment, it should be emphasized that it is associated with a number of potentially serious side effects, which may negate some or all of its potential benefits. Prevention and/or early treatment of these complications are the key to successful use of hypothermia in clinical practice. These side effects, as well as various physiological changes induced by cooling, are discussed in a separate review.

Animals↗
PubMed2003

Importance of nondrug costs of intravenous antibiotic therapy.

INTRODUCTION: Costs are one of the factors determining physicians' choice of medication to treat patients in specific situations. However, usually only the drug acquisition costs are taken into account, whereas other factors such as the use of disposable materials, the drug preparation time and the staff workload are insufficiently taken into consideration. We therefore decided to assess true overall costs of intravenous (IV) antibiotic administration by performing an activity-based costing approach. METHODS: A prospective survey on costs and workload by means of a time and motion analysis and activity-based costing was performed in a 605-bed secondary referral centre with 20 intensive care unit beds. The subjects were 50 consecutive patients admitted to our hospital with community-acquired pneumonia or intra-abdominal infections requiring treatment with IV antibiotics. A time and motion analysis of 103 routine acts of preparing and administering IV antibiotics was performed in the intensive care unit and in the Department of Internal Medicine. To measure the entire process an inventory and work flowchart were made using detailed questionnaires completed by members of the nursing staff, the medical staff and the pharmacy staff. In addition, questionnaires were distributed to management and secretarial staff to determine additional overhead costs. The average costs for different methods of IV antibiotic administration were then compared by timing all steps in the process. Four different methods of drug administration were used: administration by volumetric pump, administration by syringe pump, administration by 'unaided' infusion bag, and administration by direct IV injection. RESULTS: The average times required for each of these procedures, including preparation and administration of the drug, were 4:49 +/- 2:37, 4:56 +/- 2:03, 5:51 +/- 3:33 and 9:21 +/- 2:16 min (mean minutes:seconds +/- standard deviation), respectively. When the costs for expended staff time and materials (not including drug costs) were calculated this resulted in average costs of 5.65, 7.28, 5.36 and 3.83, respectively, for administration of each dose of antibiotics. These costs represent between 11% and 53% of the total daily costs of antibiotic therapy. Compared with the acquisition costs, these indirect costs ranged from 13% to 113%. Not included in this comparison is the time required for insertion of an IV catheter, which was found to be 10:15 +/- 6:31 min with an average calculated cost of 9.17. CONCLUSIONS: Total costs of IV antibiotic administration are formed not only by the costs of the drugs themselves, but also, to a substantial degree, by the time expended by medical and nursing staff, costs of disposable materials and overhead costs. Physicians making decisions regarding the use of specific medications in intensive care unit patients should take these factors into account. Use of IV antibiotics is associated with considerable workload and additional costs that can exceed the acquisition costs of the medications themselves.

Adult↗
PubMed2003

Changes in cerebral interstitial glycerol concentration in head-injured patients; correlation with secondary events.

OBJECTIVE: To investigate the association between the occurrence of secondary events, clinical outcome and the interstitial glycerol levels as measured with cerebral microdialysis. DESIGN: All patients received a ventriculostomy, a Camino pressure sensor and a CMA 70 microdialysis catheter. Intracranial pressure (ICP), cerebral perfusion pressure (CPP), blood pressure and arterial oxygen saturation (SaO2) were continuously monitored. Hourly microdialysis samples were collected and glycerol concentrations analyzed on-line. Glasgow Coma Score (GCS) scoring, blood gas and other laboratory analyses or investigations followed the routine of the intensive care unit. The Glasgow Outcome Scale (GOS) was assessed 6 months after injury. SETTING: Intensive Care Unit and Department of Neurosurgery, VU University Hospital. PATIENTS: Fifteen consecutive patients with severe traumatic brain injury and a GCS of 8 or less. RESULTS: No association was found between low CPP, high ICP, low PaCO2, low SaO2 or rise in temperature and the level of interstitial glycerol. In patients with a favorable outcome, the glycerol concentration never reached a level above 150 micromol/l, whereas a peak glycerol level above 150 micromol/l had a positive predictive value of 100% for an unfavorable outcome. The average of the area under the curve during the first 24 h of monitoring was significantly higher in the group with an unfavorable outcome (Kolmogorov-Smirnov test, p=0.044). CONCLUSION: Measuring interstitial glycerol for early detection of secondary adverse events, which possibly lead to secondary brain damage, does not seem useful. A peak level of interstitial glycerol above 150 micromol/l has a positive predictive value of 100% for an unfavorable outcome and hence indicates the severity of the parenchymal damage.

Adolescent↗
PubMed2003

Immunoparalysis as a cause for invasive aspergillosis?

Aspergillus infections are among the most feared opportunistic infections in humans. These organisms are ubiquitous in nature; protection against infection is usually provided by anatomical barriers and by the immune system. Tissue invasion by Aspergillus is uncommon, occurring primarily in the setting of immunosuppression. The prognosis of invasive aspergillosis is very poor. Although it is widely recognised that critically ill patients in the Intensive Care Unit (ICU) are at risk for nosocomial infections, it is not generally appreciated that such patients may also be at risk for opportunistic infections usually seen only in immunocompromised patients. This might be explained by a biphasic immunological pattern during sepsis: an early hyperinflammatory phase followed by an anti-inflammatory response, leading to a hypo-inflammatory state, the so-called compensatory anti-inflammatory response syndrome (CARS or immunoparalysis). We describe four patients admitted to our ICU for various reasons, without a history of abnormal immune function, who developed invasive pulmonary aspergillosis. We hypothesise that the occurrence of these opportunistic infections in our patients may have been due to immunoparalysis, and that perhaps all ICU patients with sepsis and multiple organ dysfunction syndrome (MODS) may be at risk for opportunistic infections such as aspergillosis as a result of this syndrome. Physicians treating critically ill patients in the ICU should be aware of the CARS/immunoparalysis syndrome and its potential to cause opportunistic infections, even in patients with normal immune function prior to ICU admission.

Aged↗
PubMed2003

Percutaneous dilatational tracheostomy in the ICU: optimal organization, low complication rates, and description of a new complication.

STUDY OBJECTIVES: To assess short-term and long-term complications of bronchoscopy-guided, percutaneous dilatational tracheostomy (PDT) and surgical tracheostomy (ST) and to report a complication of PDT that has not been described previously. DESIGN: Prospective survey. SETTING: University teaching hospital. PATIENTS: Two hundred eleven critically ill patients in our ICU. INTERVENTIONS: PDT was performed in 174 patients, under bronchoscopic guidance in most cases. ST was performed in 40 patients. RESULTS: No procedure-related fatalities occurred during PDT or ST. The incidence of significant complications (eg, procedure-related transfusion of fresh-frozen plasma, RBCs, or platelets, malpositioning or kinking of the tracheal cannula, deterioration of respiratory parameters lasting for > 36 h following the procedure, or stomal infection) in patients undergoing PDT was 4.0% overall and 3.0% when bronchoscopic guidance was used. No cases of paratracheal insertion, pneumothorax, pneumomediastinum, tracheal laceration, or clinically significant tracheal stenosis occurred in patients undergoing PDT. We attribute this low rate of complications to procedural and organizational factors such as bronchoscopic guidance, performance by or supervision of all PDTs by physicians with extensive experience in this procedure, and airway management by physicians who were well-versed in (difficult) airway management. In addition, an ear-nose-throat surgeon participated in the procedure in case conversion of the procedure to an ST should become necessary. We observed a complication that, to our knowledge, has not been reported previously. Five patients developed intermittent respiratory difficulties 2 to 21 days (mean, 8 days) after undergoing PDT. The cause turned out to be the periodic obstruction of the tracheal cannula by hematoma and the swelling of the posterior tracheal wall, which had been caused by intermittent pressure and chafing of the cannula on the tracheal wall. In between the episodes of obstruction, the cannula was open and functioning normally, which made the diagnosis difficult to establish. CONCLUSIONS: Bronchoscopy-assisted PDT is a safe and effective procedure when performed by a team of experienced physicians under controlled circumstances. The intermittent obstruction of the cannula caused by swelling and irritation of the posterior tracheal wall should be considered in patients who develop unexplained paroxysmal respiratory problems some time after undergoing PDT or ST.

Bronchoscopy↗
PubMed2002

Pediatric intensive care: result of a European survey.

OBJECTIVE: To assess and compare the structure, organisation, management, and staffing in different paediatric intensive care units (PICUs) in Europe. DESIGN: Descriptive study. SETTING: A questionnaire was sent to physicians in PICUs. Physician's names were obtained from the membership list of the European Society of Paediatric and Neonatal Intensive Care. INTERVENTIONS: None. PARTICIPANTS: Physicians from 92 European PICUs. MEASUREMENTS AND MAIN RESULTS: Responses were obtained from 92 PICUs (60% of those surveyed, 64% of hospitals with PICUs). A blank response was obtained in <2% of the questions. Considerable diversity in structure, organisation, staffing, and management in European PICUs was found. Significant differences were observed in unit size, which ranged from 2-56 (average: 8-10) beds/unit. In several--predominantly German-speaking--countries paediatric and neonatal intensive care beds are frequently combined in single units. Most European PICUs (98%) had at least part-time coverage by a paediatric intensivist; 78% had 24-h intensivist coverage. Specialized PICU nurses were present in 98% of European PICUs, and most (75%) had 24-h physician coverage by a physician with no responsibilities outside the PICU. CONCLUSIONS: Data obtained in our survey demonstrate the substantial structural, organisational management, and staff diversity of paediatric ICUs. Most European PICUs employ specialized PICU nurses and have at least part time coverage by paediatric intensivists.

Europe↗
PubMed2002

Effects of therapeutic hypothermia on intracranial pressure and outcome in patients with severe head injury.

OBJECTIVE: Therapeutic hypothermia may improve outcome in patients with severe head injury, but clinical studies have produced conflicting results. We hypothesised that the severe side effects of artificial cooling might have masked the positive effects in earlier studies, and we treated a large group of patients with severe head injury with hypothermia using a strict protocol to prevent the occurrence of cooling-induced side effects. DESIGN: Prospective clinical trial. SETTING: University teaching hospital. PATIENTS: Hundred thirty-six consecutive patients admitted to our hospital with severe head injury (Glasgow Coma Scale (GCS) < or =8). MEASUREMENTS AND RESULTS: Patients included are the 136 patients with a GCS of 8 or less on admission in whom intracranial pressure (ICP) remained above 20 mmHg in spite of therapy according to a step-up protocol. Those who responded to the last step of our protocol (barbiturate coma) constituted the control group (n=72). Those who did not respond to barbiturate coma (n=64) were treated with moderate hypothermia (32-34 degrees C). Average APACHE II scores were higher (28.9+/-14.4 vs 25.2+/-12.1, p<0.01) and average GCS at admission slightly lower (5.37+/-1.8 vs 5.9+/-2.1, p<0.05) in the hypothermia group, indicating greater severity of illness and more severe neurological injury. Predicted mortality was 86% for the hypothermia group versus 80% in controls (p<0.01). Actual mortality rates were significantly lower: 62% versus 72%; the difference in mortality between hypothermic patients and controls was significant (p<0.05). The number of patients with good neurological outcome was also higher in the hypothermia group: 15.7% versus 9.7% for hypothermic patients versus controls, respectively (p<0.02). These differences were explained almost entirely by the subgroup of patients with GCS of 5 or 6 at admission (mortality 52% vs 76%, p<0.01; good neurological outcome 29% vs 8%, p<0.01). CONCLUSIONS: Artificial cooling can significantly improve survival and neurological outcome in patients with severe head injury when used in a protocol with great attention to the prevention of side effects. Because there is likely to have been bias against the hypothermia group in this study, the positive effects of hypothermia might even have been underestimated. In addition, our results confirm the value of therapeutic hypothermia in treating refractory intracranial hypertension.

Adolescent↗
PubMed2002

Piperacillin-induced magnesium and potassium loss in intensive care unit patients.

OBJECTIVE: Broad spectrum penicillins such as piperacillin are used extensively in the intensive care unit (ICU) because of their wide bacterial spectrum and low level of toxicity. Although some cases of interstitial nephritis induced by piperacillin have been reported, this problem is thought to be rare. However, in view of the large number of other risk factors for renal disorders that are frequently present in ICU patients, we speculated that ICU patients might be more at risk for renal side effects. We therefore decided to measure serum electrolyte levels in patients before and after piperacillin administration. DESIGN: Prospective observational study. SETTING: University teaching hospital. PATIENTS AND PARTICIPANTS: Forty-three consecutive patients with normal renal function treated with piperacillin; 40 patients treated with other antibiotics. RESULTS: Serum levels of magnesium (Mg), potassium (K) and, to a lesser degree, calcium (Ca) decreased significantly in patients treated with piperacillin, but not in patients treated with other antibiotics ( p<0.01). This decrease was especially pronounced in a subgroup of patients concurrently treated with furosemide. CONCLUSIONS: We conclude that treatment with piperacillin may cause or aggravate electrolyte disorders and tubular dysfunction in ICU patients even when serum creatinine levels remain normal.

Adult↗
PubMed2001

Central venous catheter use. Part 1: mechanical complications.

Central venous catheters are being increasingly used in both intensive care units and general wards. Their use is associated with both mechanical and infectious complications. This review will focus on short- and medium-term mechanical complications of catheter placement; infectious complications will be discussed in a separate article. The most important risk factors are patient characteristics (morbidity, underlying disease and local anatomy), the expertise of the doctor performing the procedure, and nursing care. Placement aids, such as ultrasound-guided catheter insertion, are also discussed.

Adult↗