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Robert H Geelkerken

Publications and source records attributed to Robert H Geelkerken.

10 recordsLinked to original sources
PubMed2006

Consistency in endovascular aneurysm repair suitability assessment requires group decision audit.

INTRODUCTION: Proper selection of patient and stent-graft combinations in endovascular aneurysm repair (EVAR) depends on knowledge and experience with the different types of stents that have to be adapted to the patient's unique abdominal aortoiliac anatomy. The aim of this study was to analyze the consistency and variance in EVAR suitability assessment between clinicians. METHODS: Worksheets that contained anatomic data derived from computed tomography scans and angiography were compiled for 202 patients. Five clinicians, all experienced in EVAR surgery, assessed the anatomic data on the worksheets for suitability for three types of stent-grafts. The obtained 3030 assessments represented a quantification of the likelihood of success the clinician expected for effective and durable sealing and fixation of the stent-graft in EVAR. The Delphi method was used to determine consensus in the thinking process among clinicians, and kappa analysis was used to determine the proportion of variances in the assessment result between clinicians. RESULTS: With the Delphi method, Cronbach alpha values of 0.87, 0.87, and 0.90 were reached for the three types of stent-grafts in the second assessment round. The individual clinician-group correlation in round two was between 0.69 and 0.86 for clinicians 1, 2, 3, and 4. Between clinician 5 and the others, correlation varied between 0.43 and 0.64. The kappa values ranged between 0.32 and 0.51 among clinicians 1, 2, and 3. Between clinician 5 and the others, kappa values between 0.08 and 0.29 were reached. CONCLUSION: EVAR suitability estimation in a cohort of patients is highly consistent in a group of experienced clinicians. The EVAR suitability estimation at the individual patient level varies substantially between clinicians, however. Aggregating expert opinions in abdominal aortic aneurysm anatomic suitability assessment for EVAR had the opportunity to replace individual clinician decision diversification in a more solid and consistent group decision process.

Aged↗
PubMed2006

Endograft treatment of ruptured abdominal aortic aneurysms using the Talent aortouniiliac system: an international multicenter study.

OBJECTIVE: To understand the potential of endovascular aneurysm repair (EVAR) in patients presenting with a ruptured abdominal aortic aneurysm (rAAA), the proportion in whom this procedure was applicable was assessed. Mortality and morbidity was also determined in patients treated with emergency EVAR (eEVAR) when anatomic and hemodynamic conditions allowed (ie, in the entire cohort with patients receiving endovascular and open repair combined). In addition, a comparison was made between the treatment group with eEVAR and open repair. METHODS: Between February 2003 and September 2004, 10 participating institutions enrolled a representative sample of 100 consecutive patients in whom eEVAR was considered. Patients in the New Endograft treatment in Ruptured abdominal aortic Aneurysm (ERA) trial were offered eEVAR or open repair in accordance with their clinical condition or anatomic configuration. Written informed consent was obtained from all patients or their legal representatives. The study included patients who were treated by stent-graft technique or by open surgery in the case of adverse anatomy for endoluminal stent-grafting or severe hemodynamic instability, or both. Data were collated in a centralized database for analysis. The study was sponsored and supported by Medtronic, and eEVAR was uniquely performed with a Talent aortouniiliac (AUI) system in all patients. Crude and adjusted 30-day or in-hospital and 3-month mortality rates were assessed for the entire group as a whole and the EVAR and open repair category separately. Complication rates were also assessed. RESULTS: Stent-graft repair was performed in 49 patients and open surgery in 51. No significant differences were observed between these treatment groups with regard to comorbidity at presentation, hemodynamic instability, and the proportion of patients who could be assessed by preoperative computed tomography scanning. Patients with eEVAR more frequently demonstrated a suitable infrarenal neck for endovascular repair, a longer infrarenal neck, and suitable iliac arteries for access than patients with open repair. The primary reason to perform open aneurysm repair was an unfavorable configuration of the neck in 80% of the patients. In patients undergoing eEVAR, operative blood loss was less, intensive care admission time was shorter, and the duration of mechanical ventilation was shorter (P < or = .02, all comparisons). The 30-day or in-hospital mortality was 35% in the eEVAR category, 39% in patients with open repair, and 37% overall. There was no statistically significant difference between the treatment groups with regard to crude mortality rates or rates adjusted for age, gender, hemodynamic shock, and pre-existent pulmonary disease. The cumulative 3-month all-cause mortality was 40% in the eEVAR group and 42% in the open repair group (no significant differences at crude and adjusted comparisons). The 3-month primary complication rate in the two treatment groups was similar at 59%. CONCLUSIONS: In approximately half the rAAA patients, eEVAR appeared viable. An unsuitable infrarenal neck was the most frequent cause to select open repair. In dedicated centers using a Talent AUI system, eEVAR appeared to be a feasible method for treatment of a rAAA. The overall first-month mortality did not differ across treatment groups (patients with endovascular and open repair combined), yet was somewhat lower than observed in a recent meta-analysis reporting on open repair.

Aged↗
PubMed2006

Gastric exercise tonometry: the key investigation in patients with suspected celiac artery compression syndrome.

INTRODUCTION: Controversy continues about the mere existence of the celiac artery compression syndrome. Earlier results of treatment of unselected patients groups showed varying, mostly disappointing, results. The recently introduced gastric exercise tonometry test is able to identify patients with actual gastrointestinal ischemia. We prospectively studied the use of gastric exercise tonometry as a key criterion for revascularization treatment in patients with otherwise unexplained abdominal complaints and significant stenosis of the celiac artery by compression of the arcuate ligament. METHODS: Patients were prospectively selected using abdominal artery angiography and gastric exercise tonometry. Patients with a significant compression of the celiac artery, typical abdominal complaints, and abnormal tonometry were considered for revascularization. RESULTS: Over a 7-year period, 43 patients with significant celiac artery compression were included in this study, and 30 patients were diagnosed as ischemic. Twenty-nine patients had revascularization, 22 (76 %) had a trunk release only. After a median follow-up of 39 months, 83% of patients were free of symptoms. The repeated tonometry after treatment improved in 100% of patients free of symptoms, compared with 25% in patients with persistent complaints after revascularization. CONCLUSIONS: The results of this study suggest that the celiac axis compression syndrome exists and that the actual ischemia can be detected by gastric exercise tonometry and treated safely, with success.

Adolescent↗
PubMed2006

Effect of various test meals on gastric and jejunal carbon dioxide: A study in healthy subjects.

OBJECTIVE: The normal pattern of carbon dioxide (CO2) levels in the human stomach and small bowel after meals is unknown. The intraluminal carbon dioxide level is a sensitive and early marker for organ mucosal ischemia. CO2 levels in both the stomach and small bowel are influenced by multiple factors other than adequacy of perfusion. Gastric acid production, salivary bicarbonate and CO2 produced or absorbed by meals are the disturbing variables. Prolonged gastric (and jejunal) tonometry after meals can be of additional value in the work-up of patients suspected of (chronic) gastrointestinal ischemia. The purpose of this study was to challenge these problems using in vitro tested meals and a rigid acid-suppression regimen in a group of healthy subjects. MATERIAL AND METHODS: Standard meals were tested in vitro on the ability to produce and buffer CO2. Meals with the least CO2 variations were subsequently used in healthy subjects. Tonometry of the stomach and jejunum was performed for 24 h, with optimal and controlled acid suppression. RESULTS: Ten subjects were enrolled in the study. Acid production was sufficiently suppressed. The gastric PCO2 baseline (fasting) was 6.5 (1.0), and significantly lower than the jejunum PCO2 baseline of 7.6 (0.9) kPa. The gastric baseline during the day was 6.9 (1.6), and significantly lower than the gastric baseline during the night of 8.0 (1.8), suggesting a diurnal variation of PCO2. Increases in PCO2 levels were seen in all subjects, after meals and between meals. CONCLUSIONS: Prolonged gastric and jejunal tonometry is feasible in humans. PCO2 levels were seen to peak after, but also in-between, most meals. The diurnal variation in PCO2 might reflect reversible gastric mucosal ischemia.

Adult↗
PubMed2006

Implant degradation and poor healing after endovascular repair of abdominal aortic aneurysms: an analysis of explanted stent-grafts.

PURPOSE: To study explanted stent-grafts to achieve a better understanding of the mechanisms of failure after endovascular treatment of abdominal aortic aneurysms (AAA). METHODS: Twelve stent-grafts were harvested at autopsy (n=3) or during surgical conversion (n=9). Device alterations were investigated by macroscopic examination, radiography, and surface analysis techniques. Healing around the implants was studied via histology and immunohistochemistry, with particular attention to the stent-graft/tissue interface. RESULTS: Degradation was more important with Vanguard stent-grafts (off the market) than with AneuRx and Talent stent-grafts, but rupture of nitinol wires and poor surface finish in Talent stent-grafts raise concern about their corrosion resistance and long-term stability. Poor healing was observed around stent-grafts even after several years of implantation, with absence of vascular smooth muscle cells, fibroblasts, and collagen formation. In addition to the well-known foreign body reaction around the graft, numerous polymorphonuclear cells characteristic of the first step of healing were present in tissues around stent-grafts retrieved at surgical conversion. Factors explaining the lack of tissue organization around stent-grafts are discussed. CONCLUSION: The long-term stability of implants remains a concern and requires more transparency from manufacturers regarding the surface properties of their devices. Lack of neointima formation impairs biological fixation of the implant to the vessel wall, leading to possible endoleaks and migration. New-generation stent-grafts promoting biological fixation should be developed to improve clinical outcomes of this minimally invasive treatment.

Aged↗
PubMed2005

Clinical impact of gastric exercise tonometry on diagnosis and management of chronic gastrointestinal ischemia.

BACKGROUND & AIMS: Chronic gastrointestinal ischemia or chronic splanchnic syndrome is a difficult diagnosis. The use of a physiologic test, combined with clinical and anatomic data, should improve diagnostic accuracy. This study evaluates the diagnostic accuracy and clinical impact of gastric tonometry during exercise (GET) in a patient cohort suspected of chronic splanchnic syndrome. METHODS: From 1997 to 2000, 102 patients with chronic abdominal pain were analyzed. The workup included GET and selective biplane angiography. The diagnosis of gastrointestinal ischemia was based on consensus in a multidisciplinary working group and sustained on follow-up. RESULTS: Gastrointestinal ischemia was diagnosed in 38 patients. In 33 patients chronic splanchnic syndrome was found, with single vessel involvement in 20 (17 celiac artery, 3 mesenteric superior) and multivessel disease in 13. In 5 patients nonocclusive ischemia was found. By using receiver operator curve analysis, the difference between gastric and arterial partial pressure of carbon dioxide (PCO2 gradient) proved to be the best GET parameter. The criteria for diagnosing ischemia in GET were Pco2 gradient > 0.8 kPa and increase gastric PCO2, with base excess decrease <8 mmol/L during exercise. GET had 78% sensitivity and 92% specificity. Twenty-five patients underwent vascular treatment (19 operative, 6 stent/percutaneous transluminal angioplasty). After 4 years of follow-up 83% of patients were alive and free of symptoms. CONCLUSIONS: GET is an accurate diagnostic tool to show gastrointestinal ischemia. Including GET into clinical decision making enabled selecting patients with ischemia, who benefited from vascular and medical treatment. These benefits were sustained during 4-year follow-up. GET should be considered in the workup of patients with a suspected diagnosis, of gastrointestinal ischemia.

Abdominal Pain↗
PubMed2004

Effects of transfusion with red cells filtered to remove leucocytes: randomised controlled trial in patients undergoing major surgery.

OBJECTIVE: To compare postoperative complications in patients undergoing major surgery who received non-filtered or filtered red blood cell transfusions. DESIGN: Prospective, randomised, double blinded trial. SETTING: 19 hospitals throughout the Netherlands (three university; 10 clinical; six general). PARTICIPANTS: 1051 evaluable patients: 79 patients with ruptured aneurysm, 412 patients undergoing elective surgery for aneurysm, and 560 undergoing gastrointestinal surgery. INTERVENTIONS: The non-filtered products had the buffy coat removed and were plasma reduced. The filtered products had the buffy coat removed, were plasma reduced, and filtered before storage to remove leucocytes. MAIN OUTCOME MEASURES: Mortality and duration of stay in intensive care. Secondary end points were occurrence of multi-organ failure, infections, and length of hospital stay. RESULTS: No significant differences were found in mortality (odds ratio for filtered v non-filtered 0.80, 95% confidence interval 0.53 to 1.21) and in mean stay in intensive care (- 0.4 day, - 1.6 to 0.6 day). In the filtered group the mean length of hospital stay was 2.4 days shorter (- 4.8 to 0.0 day; P = 0.050) and the incidence of multi-organ failure was 30% lower (odds ratio 0.70, 0.49 to 1.00; P = 0.050). There were no differences in rates of infection (0.98, 0.73 to 1.32). CONCLUSION: The use of filtered transfusions in some types of major surgery may reduce the length of hospital stay and the incidence of postoperative multi-organ failure.

Adolescent↗
PubMed2002

Partial matrix excision or segmental phenolization for ingrowing toenails.

OBJECTIVE: To decide whether partial nail extraction with phenolisation or with partial excision of the matrix should be the standard treatment in patients with ingrowing toenails of the hallux. DESIGN: Randomized clinical trial with 12-month follow-up evaluations performed by observers who did not know which procedure was applied. SETTING: Outpatient department of a surgical teaching hospital. PATIENTS: Fifty-eight consecutive patients with a total of 63 ingrowing toenails were randomized. INTERVENTION: Thirty-four partial matrix excisions ("matrix" group) and 29 phenolizations ("phenol" group) were performed. MAIN OUTCOME MEASURES: Recurrence rate, postoperative morbidity (pain, wound exudates, and scar discomfort), and time to complete recovery (wearing shoes, performing normal activities/work). RESULTS: Recurrences were seen after 7 procedures in the matrix group and also after 7 procedures in the phenol group, of which patients were symptomatic and required a second operation in 4 and 3 instances, respectively. None of the observed differences in wound healing, postoperative pain, and recovery were statistically significant. CONCLUSIONS: Partial matrix excision and phenolization are equally effective in treating ingrowing toenails. Because the use of the toxic agent phenol should be avoided, partial matrix excision is the preferable procedure. But in view of the high recurrence rate, there is a need for further improvement of the treatment of ingrowing toenails.

Adolescent↗
PubMedDate not supplied

Endovascular treatment of traumatic thoracic aortic rupture combined with diaphragmatic rupture--a case report.

The purposes of this report are to describe the immediate repair of a diaphragmatic rupture and subsequent endovascular treatment of a thoracic aortic rupture secondary to blunt chest and abdominal trauma and to discuss the outcome in the light of the trauma scores. A 29-year-old man was injured in a car collision. There were signs of a left diaphragmatic rupture and spleen injury. After urgent laparotomy, the diaphragm was repaired. The spleen appeared uninjured; however, there was a dissection with a transmural tear of the thoracic aorta, which was subsequently treated intraluminally by using a Talent endovascular graft and two AneuRx aortic extension cuffs. The patient fully recovered, and the thoracic endograft showed no evidence of endoleak both 1 month and 1 year after treatment. Fourteen months after the operation, the patient is doing well. Endoluminal techniques can be used successfully in the immediate repair of thoracic aortic injuries, even in the presence of a diaphragmatic rupture. With the introduction of advanced repair modalities, such as endovascular techniques, mortality rates will decrease and may eventually alter injury-scoring systems such as the Injury Severity Score.

Accidents, Traffic↗