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Kees H Polderman

Publications and source records attributed to Kees H Polderman.

At least 19 recordsLinked to original sources
PubMed2006

Equipment review: cooling catheters to induce therapeutic hypothermia?

There is growing acceptance within the medical community of induced (therapeutic) hypothermia as a tool to achieve neuroprotection and/or cardioprotection. Although much work remains to be done in identifying those clinical situations in which hypothermia can be effective, there is now sufficient evidence to regard it as a standard of care, at least for some indications such as selected patients with postanoxic encephalopathy. Thus, attention is now partly shifting from assessment of the clinical evidence of efficacy to technical and implementation issues. This review provides a list of criteria by which cooling devices can be judged, and specifically it discusses one of the new cooling devices: the Alsius CoolGard 3000 device and CoolLine catheter. General aspects and advantages/disadvantages of surface versus core cooling are discussed, as are potential side effects, device-specific pros and cons, and cost-effectiveness issues. In addition, the current state of the evidence for use of induced hypothermia for various indications is briefly reviewed.

Catheterization↗
PubMed2005

Hospital-acquired sinusitis is a common cause of fever of unknown origin in orotracheally intubated critically ill patients.

INTRODUCTION: Sinusitis is a well recognised but insufficiently understood complication of critical illness. It has been linked to nasotracheal intubation, but its occurrence after orotracheal intubation is less clear. We studied the incidence of sinusitis in patients with fever of unknown origin (FUO) in our intensive care unit with the aim of establishing a protocol that would be applicable in everyday clinical practice. METHODS: Sinus X-rays (SXRs) were performed in all patients with fever for which an initial screening (physical examination, microbiological cultures and chest X-ray) revealed no obvious cause. All patients were followed with a predefined protocol, including antral drainage in all patients with abnormal or equivocal results on their SXR. RESULTS: Initial screening revealed probable causes of fever in 153 of 351 patients (43.6%). SXRs were taken in the other 198 patients (56.4%); 129 had obvious or equivocal abnormalities. Sinus drainage revealed purulent material and positive cultures (predominantly Pseudomonas and Klebsiella species) in 84 patients. Final diagnosis for the cause of fever in all 351 patients based on X-ray results, microbiological cultures, and clinical response to sinus drainage indicated sinusitis as the sole cause of fever in 57 (16.2%) and as contributing factor in 48 (13.8%) patients with FUO. This will underestimate the actual incidence because SXR and drainage were not performed in all patients. CONCLUSION: Physicians treating critically ill patients should be aware of the high risk of sinusitis and take appropriate preventive measures, including the removal of nasogastric tubes in patients requiring long-term mechanical ventilation. Routine investigation of FUO should include computed tomography scan, SXR or sinus ultrasonography, and drainage should be performed if any abnormalities are found.

Clinical Protocols↗
PubMed2005

Effect of training and strict guidelines on the reliability of risk adjustment systems in paediatric intensive care.

OBJECTIVE: Many risk-adjustment systems have significant interobserver variability in everyday clinical practice. This can be partly corrected by strict guidelines and training. These issues have not been well studied in the paediatric setting. We assessed the reliability of two widely used paediatric scoring systems, the Paediatric Risk of Mortality (PRISM) and Paediatric Index of Mortality (PIM), before and after a special training program. DESIGN: Prospective observational multi-centred cohort study. INTERVENTION: Twenty-seven physicians from five paediatric intensive care units (PICUs) assessed severity of illness in 20 selected patients using PRISM and PIM scores before and after a special training program. Physicians were divided according to level of PICU experience: intensivists (>3 years experience, n=12), fellows (6-30 months experience, n=6) and residents (<6 months experience, n=9). Intraclass correlation was used to compare scoring reliability before and after training. MEASUREMENTS AND RESULTS: Wide variability in PRISM and PIM scoring was observed before training (intraclass correlation for PRISM scores 0.24-0.73, intraclass correlation for PIM scores 0.16-0.33). Training and implementation of guidelines led to significant increases in interobserver agreement (intraclass correlation 0.74-0.86 for PRISM and 0.88-0.95 for PIM scores), although some variability remained. CONCLUSION: Our results show that the reliability of PRISM and PIM risk adjustment systems in daily clinical practice is much lower than expected. Training and guidelines can significantly increase interobserver agreement. These factors should be taken into account when using these systems for benchmarking, or to compare quality of care between different PICUs.

Educational Status↗
PubMed2005

Dealing with the delirium dilemma.

Delirium is a frequently occurring but often under-diagnosed and under-treated problem in the intensive care unit (ICU). It has been linked to adverse outcome, increased length of stay and higher mortality in critically ill patients. A study by Thomason and coworkers published in this issue of Critical Care deals with the issue of delirium and its consequences in less severely ill patients. This commentary aims to provide context for this study, discussing its potential implications as well as the potential therapeutic and preventive measures in patients with hyperactive or hypoactive delirium.

Analgesics, Opioid↗
PubMed2005

Acute lung injury, overhydration or both?

Acute lung injury or acute respiratory distress syndrome (ALI/ARDS) in the course of sepsis is thought to result from increased pulmonary capillary permeability and resultant edema. However, when the edema is assessed at the bedside by measuring the extravascular thermal volume by transpulmonary dilution, some ALI/ARDS patients with sepsis may have normal extravascular lung water (EVLW). Conversely, a raised EVLW may be present even when criteria for ALI/ARDS are not met, according to GS Martin and colleagues in this issue of Critical Care. This commentary puts the findings into a broader perspective and focuses on the difficulty, at the bedside, in recognizing and separating various types of pulmonary edema. Some of these forms of edema, classically differentiated on the basis of increased permeability and cardiogenic/hydrostatic factors, may overlap, whereas the criteria for ALI/ARDS may be loose, poorly reproducible, relatively insensitive and nonspecific, and highly therapy-dependent. Overhydration is particularly difficult to recognize. Additional diagnostics may be required to improve the delineation of pulmonary edema so as to redirect or redefine treatment and improve patient morbidity and, perhaps, mortality. Monitoring EVLW by single transpulmonary thermal dilution, for instance, might have a future role in this process.

Diagnosis, Differential↗
PubMed2005

Induction of hypothermia in patients with various types of neurologic injury with use of large volumes of ice-cold intravenous fluid.

OBJECTIVE: Mounting evidence suggests that mild to moderate hypothermia can mitigate neurologic and myocardial injury. The speed of induction appears to be a key factor in determining its efficacy. However, even when the fastest currently available cooling techniques are used, reaching target temperatures takes at least 2 hrs and usually longer. We hypothesized that infusion of refrigerated fluids could be a safe accessory method to increase cooling speed. DESIGN: Prospective intervention study. SETTING: University teaching hospital. PATIENTS: One hundred thirty-four patients with various types of neurologic injury (postanoxic encephalopathy, subarachnoid hemorrhage, or traumatic brain injury). MEASUREMENTS AND MAIN RESULTS: Hypothermia was induced in 134 patients with various types of neurologic injury, by means ice-water cooling blankets and infusion of refrigerated (4 degrees C) saline (110 patients) or saline and colloids (24 patients). An average volume of 2340 +/- 890 mL of refrigerated fluids was infused in 50 mins. Core temperatures decreased from 36.9 +/- 1.9 degrees C to 34.6 +/- 1.5 degrees C at t = 30 mins and to 32.9 +/- 0.9 degrees C at t = 60 mins (target temperature: 32 degrees C-33 degrees C). Monitoring of blood pressure, heart rhythm, central venous pressure, blood gasses, electrolyte and glucose levels, and platelet and white blood cell count revealed no additional adverse effects. Mean arterial pressure increased by 15 mm Hg, with larger increases in blood pressure occurring in hemodynamically unstable patients. No patient developed pulmonary edema. CONCLUSIONS: Induction of hypothermia by means of cold-fluid infusion combined with ice-water cooling blankets is safe, efficacious, and quick. Because the speed of cooling is important to increase its protective effects, we recommend that cold-fluid infusion be used in all patients treated with induced hypothermia. This should be combined with another method to safely and accurately maintain hypothermia once target temperatures have been reached.

Adolescent↗
PubMed2005

Central venous catheter use in the pediatric patient: mechanical and infectious complications.

OBJECTIVE: Following the introduction and widespread use of central venous catheters (CVCs) in adults, these devices are being used with increasing frequency in the pediatric population. This review will focus on differences between adults and children regarding CVC use and its potential complications. Both mechanical and infectious complications will be discussed. DATA SOURCES: Systematic review of the literature. CONCLUSIONS: CVC-related complications in pediatric patients are closely linked to age, body size, and age-related immune status. In older children, many complications are similar to those encountered in adult patients. Because of ongoing growth and body changes, a cutoff point beyond which children can be regarded as "young adults" is difficult to define; many of our recommendations are therefore age-related. More frequently than in adults, an implanted port may be the first choice in pediatric patients when long indwelling times are expected. The optimal site of insertion also depends on factors such as the patients' age as well as the need for sedation and analgesia during the insertion procedure. In contrast to guidelines in adult patients, we recommend that a radiograph always be made following CVC insertion to check the position of the catheter. Regarding prevention of infectious complications, we recommend full sterile barrier precautions during CVC insertion and strict protocols for catheter care. CVCs should be removed as soon as possible when they are no longer needed, but there is no place for elective CVC replacement on a routine basis. New developments such as the use of impregnated catheters might help reduce infection rates; however, additional research will be required to provide more evidence of benefit in the pediatric population.

Adult↗
PubMed2004

Severe electrolyte disorders following cardiac surgery: a prospective controlled observational study.

INTRODUCTION: Electrolyte disorders are an important cause of ventricular and supraventricular arrhythmias as well as various other complications in the intensive care unit. Patients undergoing cardiac surgery are at risk for development of tachyarrhythmias, especially in the period during and immediately after surgical intervention. Preventing electrolyte disorders is thus an important goal of therapy in such patients. However, although levels of potassium are usually measured regularly in these patients, other electrolytes such as magnesium, phosphate and calcium are measured far less frequently. We hypothesized that patients undergoing cardiac surgical procedures might be at risk for electrolyte depletion, and we therefore conducted the present study to assess electrolyte levels in such patients. METHODS: Levels of magnesium, phosphate, potassium, calcium and sodium were measured in 500 consecutive patients undergoing various cardiac surgical procedures who required extracorporeal circulation (group 1). A total of 250 patients admitted to the intensive care unit following other major surgical procedures served as control individuals (group 2). Urine electrolyte excretion was measured in a subgroup of 50 patients in both groups. RESULTS: All cardiac patients received 1 l cardioplegia solution containing 16 mmol potassium and 16 mmol magnesium. In addition, intravenous potassium supplementation was greater in cardiac surgery patients (mean +/- standard error: 10.2 +/- 4.8 mmol/hour in cardiac surgery patients versus 1.3 +/- 1.0 in control individuals; P < 0.01), and most (76% versus 2%; P < 0.01) received one or more doses of magnesium (on average 2.1 g) for clinical reasons, mostly intraoperative arrhythmia. Despite these differences in supplementation, electrolyte levels decreased significantly in cardiac surgery patients, most of whom (88% of cardiac surgery patients versus 20% of control individuals; P < 0.001) met criteria for clinical deficiency in one or more electrolytes. Electrolyte levels were as follows (mmol/l [mean +/- standard error]; cardiac patients versus control individuals): phosphate 0.43 +/- 0.22 versus 0.92 +/- 0.32 (P < 0.001); magnesium 0.62 +/- 0.24 versus 0.95 +/- 0.27 (P < 0.001); calcium 1.96 +/- 0.41 versus 2.12 +/- 0.33 (P < 0.001); and potassium 3.6 +/- 0.70 versus 3.9 +/- 0.63 (P < 0.01). Magnesium levels in patients who had not received supplementation were 0.47 +/- 0.16 mmol/l in group 1 and 0.95 +/- 0.26 mmol/l in group 2 (P < 0.001). Urinary excretion of potassium, magnesium and phosphate was high in group 1 (data not shown), but this alone could not completely account for the observed electrolyte depletion. CONCLUSION: Patients undergoing cardiac surgery with extracorporeal circulation are at high risk for electrolyte depletion, despite supplementation of some electrolytes, such as potassium. The probable mechanism is a combination of increased urinary excretion and intracellular shift induced by a combination of extracorporeal circulation and decreased body temperature during surgery (hypothermia induced diuresis). Our findings may partly explain the high risk of tachyarrhythmia in patients who have undergone cardiac surgery. Prophylactic supplementation of potassium, magnesium and phosphate should be seriously considered in all patients undergoing cardiac surgical procedures, both during surgery and in the immediate postoperative period. Levels of these electrolytes should be monitored frequently in such patients.

Adult↗
PubMed2004

Novel applications of therapeutic hypothermia: report of three cases.

Therapeutic hypothermia can provide neuroprotection in various situations where global or focal neurological injury has occurred. Hypothermia has been shown to be effective in a large number of animal experiments. In clinical trials, hypothermia has been used in patients with postanoxic injury following cardiopulmonary resuscitation, in traumatic brain injury with high intracranial pressure, in the perioperative setting during various surgical procedures and for various other indications. There is thus evidence that hypothermia can be effective in various situations of neurological injury, although a number of questions remain unanswered. We describe three patients with unusual causes of neurological injury, whose clinical situation was in fundamental aspects analogous to conditions where hypothermia has been shown to be effective.

Brain Injuries↗
PubMed2004

Drug intervention trials in sepsis: divergent results.

CONTEXT: Important advances have been made in our understanding of severe sepsis. Outcome can be improved by targeted interventions, including early and appropriate antibiotic therapy and goal-directed resuscitation, and might be further improved by selective decontamination of the digestive tract, tight control of glucose, and possibly by giving corticosteroids to selected patients. Drugs that target specific steps in the septic cascade include cytokine inhibitors, anti-endotoxins, and the three naturally occurring anticoagulants. Only one of these trials, which assessed the efficacy of activated protein C, reported significant improvements in outcome. Translation of these results into practice has been hampered by high drug costs, and by apparent discrepancies between interim results and final outcomes in two of the trials with natural anticoagulants. STARTING POINT: Recently, Steven Opal and colleagues (Crit Care Med 2004; 32: 332-41) reported a randomised trial with platelet-activating-factor acetylhydrolase to suppress the inflammatory response in septic patients. No effects on outcome were observed (mortality 24% with placebo vs 25% with the intervention). By contrast, Jose Garnacho-Montero and colleagues, in a cohort study (Crit Care Med 2003; 31: 2742-51), saw large mortality reductions with initially appropriate choice of antibiotics in septic patients (19.8% reduction overall and 43.4% in patients with septic shock). These benefits were higher than those even in the most successful trial with an antisepsis agents, underscoring the importance of basic measures in severe sepsis. WHERE NEXT? Initial management in severe sepsis should include early goal-directed fluid resuscitation, appropriate antibiotic treatment, and surgical-site control. Intensive-care units should be run by specialists, with adequate medical and nursing staffing. Tight regulation of glucose, selective decontamination of the digestive tract, and moderate-dose corticosteroids in selected cases should be considered. Expensive new drugs, such as activated protein C, might further improve outcome, but should be considered only when organisational aspects and supportive care have been optimised.

Antithrombin III↗