Long axial field of view PET/CT in critically ill patients: lessons from a case report.

The introduction of new long axial field of view (LAFOV) scanners is a major milestone in positron emission tomography/computed tomography (PET/CT) imaging. With these new systems a revolutionary reduction in scan time can be achieved, concurrently lowering tracer dose. Therefore, PET/CT has come within reach for groups of patients in whom PET/CT previously was undesirable. In this case report we discuss the procedure of a continuous bed motion (CBM) total-body [18F]FDG PET/CT scan in an intensive care patient. We emphasize the clinical and technical possibilities with this new camera system, a matched clinical protocol, and the added value of a dedicated team.

Time courses of urinary creatinine excretion, measured creatinine clearance and estimated glomerular filtration rate over 30 days of ICU admission.

PURPOSE: Baseline urinary creatinine excretion (UCE) is associated with ICU outcome, but its time course is not known. MATERIALS AND METHODS: We determined changes in UCE, plasma creatinine, measured creatinine clearance (mCC) and estimated glomerular filtration (eGFR) in patients with an ICU-stay ≥30d without acute kidney injury stage 3. The Cockcroft-Gault, MDRD (modification of diet in renal disease) and CKD-EPI (chronic kidney disease epidemiology collaboration) equations were used. RESULTS: In 248 patients with 5143 UCEs hospital mortality was 24%. Over 30d, UCE absolutely decreased in male survivors and non-survivors and female survivors and nonsurvivors by 0.19, 0.16, 0.10 and 0.05 mmol/d/d (all P < 0.001). Relative decreases in UCE were similar in all four groups: 1.3, 1.4, 1.2 and 0.9%/d respectively. Over 30d, mCC remained unchanged, but eGFR rose by 31% (CKD-EPI) and 73% (MDRD) and creatinine clearance estimated by Cockcroft-Gault by 59% (all P < 0.001). CONCLUSIONS: Over 1 month of ICU stay, UCE declined by ≥1%/d which may correspond to an equivalent decline in muscle mass. These rates of UCE decrease were similar in survivors, non-survivors, males and females underscoring the intransigent nature of this process. In contrast to measured creatinine clearance, estimates of eGFR progressively rose during ICU stay.

Machine learning in infection management using routine electronic health records: tools, techniques, and reporting of future technologies.

BACKGROUND: Machine learning (ML) is increasingly being used in many areas of health care. Its use in infection management is catching up as identified in a recent review in this journal. We present here a complementary review to this work. OBJECTIVES: To support clinicians and researchers in navigating through the methodological aspects of ML approaches in the field of infection management. SOURCES: A Medline search was performed with the keywords artificial intelligence, machine learning, infection∗, and infectious disease∗ for the years 2014-2019. Studies using routinely available electronic hospital record data from an inpatient setting with a focus on bacterial and fungal infections were included. CONTENT: Fifty-two studies were included and divided into six groups based on their focus. These studies covered detection/prediction of sepsis (n = 19), hospital-acquired infections (n = 11), surgical site infections and other postoperative infections (n = 11), microbiological test results (n = 4), infections in general (n = 2), musculoskeletal infections (n = 2), and other topics (urinary tract infections, deep fungal infections, antimicrobial prescriptions; n = 1 each). In total, 35 different ML techniques were used. Logistic regression was applied in 18 studies followed by random forest, support vector machines, and artificial neural networks in 18, 12, and seven studies, respectively. Overall, the studies were very heterogeneous in their approach and their reporting. Detailed information on data handling and software code was often missing. Validation on new datasets and/or in other institutions was rarely done. Clinical studies on the impact of ML in infection management were lacking. IMPLICATIONS: Promising approaches for ML use in infectious diseases were identified. But building trust in these new technologies will require improved reporting. Explainability and interpretability of the models used were rarely addressed and should be further explored. Independent model validation and clinical studies evaluating the added value of ML approaches are needed.

A patient with acute liver failure and extreme hypoglycaemia with lactic acidosis who was not in a coma: causes and consequences of lactate-protected hypoglycaemia.

Lactate can substitute for glucose as a metabolic substrate. We report a patient with acute liver failure who was awake despite a glucose level of 0.7 mmol/l with very high lactate level of 25 mmol/l. The hypoglycaemia+hyperlactataemia combination may be considered paradoxical since glucose is the main precursor of lactate and lactate is reconverted into glucose by the Cori cycle. Literature relevant to the underlying mechanism of combined deep hypoglycaemia and severe hyperlactataemia was assessed. We also assessed the literature for evidence of protection against deep hypoglycaemia by hyperlactataemia. Four syndromes demonstrating hypoglycaemia+hyperlactataemia were found: 1) paracetamol-induced acute liver failure, 2) severe malaria, 3) lymphoma and 4) glucose-6-phosphatase deficiency. An impaired Cori cycle is a key component in all of these metabolic states. Apparently the liver, after exhausting its glycogen stores, loses the gluconeogenic pathway to generate glucose and thereby its ability to remove lactate as well. Several patients with lactic acidosis and glucose levels below 1.7 mmol/l who were not in a coma have been reported. These observations and other data coherently indicate that lactate-protected hypoglycaemia is, at least transiently, a viable state under experimental and clinical conditions. Severe hypoglycaemia+hyperlactataemia reflects failure of the gluconeogenic pathway of lactate metabolism. The existence of lactate-protected hypoglycaemia implies that patients who present with this metabolic state should not automatically be considered to have sustained irreversible brain damage. Moreover, therapies that aim to achieve hypoglycaemia might be feasible with concomitant hyperlactataemia.

Ex vivo normothermic machine perfusion and viability testing of discarded human donor livers.

In contrast to traditional static cold preservation of donor livers, normothermic machine perfusion may reduce preservation injury, improve graft viability and potentially allows ex vivo assessment of graft viability before transplantation. We have studied the feasibility of normothermic machine perfusion in four discarded human donor livers. Normothermic machine perfusion consisted of pressure and temperature controlled pulsatile perfusion of the hepatic artery and continuous portal perfusion for 6 h. Two hollow fiber membrane oxygenators provided oxygenation of the perfusion fluid. Biochemical markers in the perfusion fluid reflected minimal hepatic injury and improving function. Lactate levels decreased to normal values, reflecting active metabolism by the liver (mean lactate 10.0 ± 2.3 mmol/L at 30 min to 2.3 ± 1.2 mmol/L at 6 h). Bile production was observed throughout the 6 h perfusion period (mean rate 8.16 ± 0.65 g/h after the first hour). Histological examination before and after 6 h of perfusion showed well-preserved liver morphology without signs of additional hepatocellular ischemia, biliary injury or sinusoidal damage. In conclusion, this study shows that normothermic machine perfusion of human donor livers is technically feasible. It allows assessment of graft viability before transplantation, which opens new avenues for organ selection, therapeutic interventions and preconditioning.

Preventability of trauma deaths in a Dutch Level-1 trauma centre.

BACKGROUND: Monitoring the quality of trauma care is frequently done by analysing the preventability of trauma deaths and errors during trauma care. In the Academic Medical Center trauma deaths are discussed during a monthly Morbidity and Mortality meeting. In this study an external multidisciplinary panel assessed the trauma deaths and errors in management of a Dutch Level-1 trauma centre for (potential) preventability. METHODS: All patients who died during or after presentation in the trauma resuscitation room in a 2-year period were eligible for review. All information on trauma evaluation and management was summarised by an independent research fellow. An external multidisciplinary panel individually evaluated the cases for preventability of death. Potential errors or mismanagements during the admission were classified for type, phase and domain. Overall agreement on (potential) preventability was compared between the external panel and the internal M&M consensus. RESULTS: Of the 62 evaluated trauma deaths one was judged as preventable and 17 were judged as potentially preventable by the review panel. Overall agreement on preventability between the review panel and the internal consensus was moderate (Kappa 0.51). The external panel judged one death as preventable compared with three from the internal consensus. The interobserver agreement between the external panel members was also moderate (Kappa 0.43). The panel judged 31 errors to have occurred in the (potential) preventable death group and 23 errors in the non-preventable death group. Such errors included choice or sequence of diagnostics, rewarming of hypothermic patients, and correction of coagulopathies. CONCLUSIONS: The preventable death rate in the present study was comparable to data in the available literature. Compared to internal review, the external, multidisciplinary review did not find a higher preventable death rate, although it provided several insights to optimise trauma care.

Elevated lactate during psychogenic hyperventilation.

STUDY OBJECTIVE: Elevated arterial lactate levels are closely related to morbidity and mortality in various patient categories. In the present retrospective study, the relation between arterial lactate, partial pressure of carbon dioxide (Pco(2)) and pH was systematically investigated in patients who visited the emergency department (ED) with psychogenic hyperventilation. METHODS: Over a 5-month period, all the patients who visited the ED of a university hospital with presumed psychogenic hyperventilation were evaluated. Psychogenic hyperventilation was presumed to be present when an increased respiratory rate (>20 min) was documented at or before the ED visit and when somatic causes explaining the hyperventilation were absent. Arterial blood gas and lactate levels (reference values 0.5-1.5 mmol/l) were immediately measured by a point-of-care analyser that was managed and calibrated by the central laboratory. RESULTS: During the study period, 46 patients were diagnosed as having psychogenic hyperventilation. The median (range) Pco(2) for this group was 4.3 (2.0-5.5) kPa, the pH was 7.47 (7.40-7.68) and the lactate level was 1.2 (0.5-4.4) mmol/l. 14 participants (30%) had a lactate level above the reference value of 1.5 mmol/l. Pco(2) was the most important predictor of lactate in multivariate analysis. None of the participants underwent any medical treatment other than observation at the ED or had been hospitalised after their ED visit. CONCLUSIONS: In patients with psychogenic hyperventilation, lactate levels are frequently elevated. Whereas high lactates are usually associated with acidosis and an increased risk of poor outcome, in patients with psychogenic hyperventilation, high lactates are associated with hypocapnia and alkalosis. In this context, elevated arterial lactate levels should not be regarded as an adverse sign.

Extended esophagectomy in elderly patients with esophageal cancer: minor effect of age alone in determining the postoperative course and survival.

BACKGROUND: Elderly patients who undergo esophagectomy for cancer often have a high prevalence of coexisting diseases, which may adversely affect their postoperative course. We determined the relationship of advanced age (i.e., > or =70 years) with outcome and evaluated age as a selection criterion for surgery. METHODS: Between January 1991 and January 2007, we performed a curative-intent extended transthoracic esophagectomy in 234 patients with cancer of the esophagus. Patients were divided into two age groups: <70 years (group I; 170 patients) and > or =70 years (group II; 64 patients). RESULTS: Both groups were comparable regarding comorbidity (American Society of Anesthesiologists classification), and tumor and surgical characteristics. The overall in-hospital mortality rate was 6.2% (group I, 5%, vs. group II, 11%, P = 0.09). Advanced age was not a prognostic factor for developing postoperative complications (odds ratio, 1.578; 95% confidence interval, 0.857-2.904; P = 0.143). The overall number of complications was equal with 58% in group I vs. 69% in group II (P = 0.142). Moreover, the occurrence of complications in elderly patients did not influence survival (P = 0.174). Recurrences developed more in patients <70 years (58% vs. 42%, P = 0.028). The overall 5-year survival was 35%, and, when included, postoperative mortality was 33% in both groups (P = 0.676).The presence of comorbidity was an independent prognostic factor for survival (P = 0.002). CONCLUSIONS: Advanced age (> or =70 years) has minor influence on postoperative course, recurrent disease, and survival in patients who underwent an extended esophagectomy. Age alone is not a prognostic indicator for survival. We propose that a radical resection should not be withheld in elderly patients with limited frailty and comorbidity.

Treatment of presumed acute cardiogenic pulmonary oedema in an ambulance system by nurses using Boussignac continuous positive airway pressure.

BACKGROUND: Early initiation of continuous positive airway pressure (CPAP) applied by face mask benefits patients with acute cardiogenic pulmonary oedema (ACPE). The simple disposable Boussignac CPAP (BCPAP) has been used in ambulances by physicians. In the Netherlands, ambulances are manned by nurses and not physicians. It was hypothesised that ambulance nurses are able to identify patients with ACPE and can successfully apply BCPAP. A prospective case series of patients with presumed ACPE treated with BCPAP by ambulance nurses is described. METHODS: After training of ambulance nurses, all 33 ambulances in the region were equipped with BCPAP. ACPE was diagnosed on clinical signs and pulse oximetry saturation (Spo(2)) <95%. BCPAP (5 cm H(2)O, Fio(2)>80%) was generated with an oxygen flow of 15 l/min. The physiological responses, experiences and clinical outcomes of the patients were collected from ambulance and hospital records, and ambulance nurses and patients received a questionnaire. RESULTS: From March to December 2006, 32 patients (age range 61-94 years) received BCPAP during transport to six different regional hospitals. In 26 patients (81%) a diagnosis of ACPE was confirmed. With BCPAP, median (IQR) Spo(2) increased from 79% (69-94%) to 96% (89-98%) within 20 min. The median (IQR) duration of BCPAP treatment was 26 min (21-32). The patients had no negative recollections of the treatment. Ambulance personnel were satisfied with the BCPAP therapy. CONCLUSION: When applied by ambulance nurses, BCPAP was feasible and effective in improving oxygen saturation in patients with ACPE. Although survival benefit can only be demonstrated by further research, it is considered that BCPAP can be implemented in all ambulances in the Netherlands.

Impact of splenectomy on surgical outcome in patients with cancer of the distal esophagus and gastro-esophageal junction.

We aim to determine the effect of splenectomy on clinical outcome in patients with cancer of the distal esophagus and gastro-esophageal junction (GEJ) after a curative intended resection. From January 1991 to July 2004, 210 patients underwent a potentially curative gastroesophageal resection with an extended nodal dissection. The study group was divided into: group I with splenectomy, consisting of 66 patients (31.4%), and group II without splenectomy, of 144 patients. Splenectomy was performed for oncological reasons. Medical records were reviewed retrospectively. Postoperative complications occurred in 27 patients (40.9%) in group I and in 68 patients (47.2%) in group II (P = 0.4). The overall mortality was not significantly different between both groups (P = 0.7). There was a higher administration of red blood cells during surgery (P < or = 0.001), increased operating room (OR) time (P < or = 0.001) and longer intensive care unit (ICU) stay (P = 0.01) in group I. Independent prognostic factors for survival were outcome of surgery, nodal metastases, gender, complications and ICU stay. Sepsis was a strong prognostic factor among the complications. The 1 and 2-year survival was significantly higher in group II; 75% and 67% (P = 0.032) compared to 69% and 56% (P = 0.017) in group I, respectively. However, the 5-year survival was not different in both groups (29% in group I and 60% in group II, P = 0.191). Splenectomy had no marked effect on mortality and morbidity after curative resection of esophageal cancer. Splenectomy had a significant increase in blood transfusions with prolonged OR time and ICU stay and decreased short-term survival.

Heme oxygenase-1 genotype of the donor is associated with graft survival after liver transplantation.

Heme oxygenase-1 (HO-1) has been suggested as a cytoprotective gene during liver transplantation. Inducibility of HO-1 is modulated by a (GT)(n) polymorphism and a single nucleotide polymorphism (SNP) A(-413)T in the promoter. Both a short (GT)(n) allele and the A-allele have been associated with increased HO-1 promoter activity. In 308 liver transplantations, we assessed donor HO-1 genotype and correlated this with outcome variables. For (GT)(n) genotype, livers were divided into two classes: short alleles (<25 repeats; class S) and long alleles (> or =25 repeats; class L). In a subset, hepatic messenger ribonucleic acid (mRNA) expression was correlated with genotypes. Graft survival at 1 year was significantly better for A-allele genotype compared to TT-genotype (84% vs. 63%, p = 0.004). Graft loss due to primary dysfunction (PDF) occurred more frequently in TT-genotype compared to A-receivers (p = 0.03). Recipients of a liver with TT-genotype had significantly higher serum transaminases after transplantation and hepatic HO-1 mRNA levels were significantly lower compared to the A-allele livers (p = 0.03). No differences were found for any outcome variable between class S and LL-variant of the (GT)(n) polymorphism. Haplotype analysis confirmed dominance of the A(-413)T SNP over the (GT)(n) polymorphism. In conclusion, HO-1 genotype is associated with outcome after liver transplantation. These findings suggest that HO-1 mediates graft survival after liver transplantation.

The impact of aprotinin on renal function after liver transplantation: an analysis of 1,043 patients.

Renal dysfunction is frequently seen after orthotopic liver transplantation (OLT). Aprotinin is an antifibrinolytic drug which reduces blood loss during OLT. Recent studies in cardiac surgery suggested a higher risk of postoperative renal complications when aprotinin is used. The impact of aprotinin on renal function after OLT, however, is unknown. In 1,043 adults undergoing OLT, we compared postoperative renal function in patients who received aprotinin (n = 653) or not (n = 390). Using propensity score stratification (C-index 0.82) and multivariate regression analysis, aprotinin was identified as a risk factor for severe renal dysfunction within the first week, defined as increase in serum creatinine by >or= 100% (OR = 1.97, 95% CI = 1.14-3.39; p = 0.02). No differences in renal function were noted at 30 and 365 days postoperatively. Moreover, no significant differences were found in the need for renal replacement therapy (OR = 1.52, 95% CI = 0.94-2.46; p = 0.11) or in 1-year patient survival rate (OR = 1.14, 95% CI = 0.73-1.77; p = 0.64) in patients who received aprotinin or not. In conclusion, aprotinin is associated with a higher risk of transient renal dysfunction in the first week after OLT, but not with a higher need for postoperative renal replacement therapy or an increased risk of mortality.

Results of streamlined regional ambulance transport and subsequent treatment of acute abdominal aortic aneurysms.

OBJECTIVE: To describe the triage of patients operated for non-ruptured and ruptured abdominal aortic aneurysms (AAAs) before the endovascular era. DESIGN: Retrospective single-centre cohort study. METHODS: All patients treated for an acute AAA between 1998 and 2001 and admitted to our hospital were evaluated in the emergency department for urgent AAA surgery. All time intervals, from the telephone call from the patient to the ambulance department, to the arrival of the patient in the operating theatre, were analysed. Intraoperative, hospital and 1-year survival were determined. RESULTS: 160 patients with an acute AAA were transported to our hospital. Mean (SD) age was 71 (8) years, and 138 (86%) were men. 34 (21%) of these patients had symptomatic, non-ruptured AAA (sAAA) and 126 patients had ruptured AAA (rAAA). All patients with sAAA and 98% of patients with rAAA were operated upon. For the patients with rAAA, median time from telephone call to arrival at the hospital was 43 min (interquartile range 33-53 min) and median time from arrival at the hospital to arrival at the operating room was 25 min (interquartile range 11-50 min). Intraoperative mortality was 0% for sAAA and 11% for rAAA (p = 0.042), and hospital mortality was 12% and 33%, respectively (p = 0.014). CONCLUSIONS: A multidisciplinary unified strategy resulted in a rapid throughput of patients with acute AAA. Rapid transport, diagnosis and surgery resulted in favourable hospital mortality. Despite the fact that nearly all the patients were operated upon, survival was favourable compared with published data.

Walking with continuous positive airway pressure.

A ventilator-dependent child had been in the paediatric intensive care unit (PICU) ever since birth. As a result, she had fallen behind considerably in her development. After 18 months, continuous positive airway pressure was successfully administered via a tracheostomy tube with a novel lightweight device. This enabled her to walk in the PICU. With this device, the child was discharged home where she could walk with an action range of 10 m. Subsequently, her psychomotor development improved remarkably. To the authors' knowledge, this is the first case report of a patient, adult or paediatric, who could actually walk with a sufficient radius of action while receiving long-term respiratory support.

Refractory hyperglycaemia induced by glucose-insulin-potassium infusion in acute myocardial infarction.

BACKGROUND: Recent randomised clinical trials have not confirmed the beneficial effects of glucose-insulin-potassium (GIK) infusion observed in experimental models of myocardial ischaemia and infarction. METHODS: We investigated glucose levels and insulin dose in 107 patients treated with reperfusion therapy and GIK for acute myocardial infarction. RESULTS: Despite high insulin infusion rates, persistent hyperglycaemia occurred in 37% of the patients. These patients had significantly larger infarctions, as measured by enzyme release (p=0.006). In a multivariate model predicting high troponin levels, refractory hyperglycaemia remained a significant parameter (p=0.02). CONCLUSION: These findings suggest that refractory hyperglycaemia caused by high-dose glucose infusion may, at least in part, explain the discrepancy between the experimental and clinical data.

Glucose and potassium derangements by glucose-insulin-potassium infusion in acute myocardial infarction.

BACKGROUND: High-dose glucose-insulin-potassium infusion (GIK) has been suggested to be beneficial in acute myocardial infarction (MI). Recently new large trials have shown no effect of GIK on mortality. To investigate whether metabolic derangement could have negated the potential beneficial effect, we studied the relation between systemic glucose and potassium levels and outcome. METHODS: Patients with signs and symptoms of ST-segment-elevation MI and treated with primary percutaneous coronary intervention (PCI) were randomised to no infusion or high-dose GIK, i.e. 80 mmol potassium chloride in 500 ml 20% glucose at a rate of 3 ml/kg/hour and 50 units short-acting insulin in 50 ml 0.9% sodium chloride for 12 hours. RESULTS: A total of 6991 glucose values and 7198 potassium values were obtained in 476 GIK patients and 464 controls. Mean serum glucose was significantly higher in the GIK group (9.3±4.5 mmol/l vs. 8.4±2.9 mmol/l, p<0.001). Mean potassium level was significantly higher in the GIK group (4.2±0.5 mmol/l vs. 3.9±0.4 mmol/l, p<0.001). Incidence of hyperglycaemia (glucose >11.0 mmol/l) occurred in 70.8% of GIK patients and 33.8% of controls (p<0.001). Hypokalaemia was less common in the GIK group (23.5 vs. 41.2%, p<0.001). Incidence of hyperkalaemia and hypoglycaemia did not differ significantly between the two groups. In multivariate analysis age, previous cardiovascular disease, Killip class >1, unsuccessful PCI and mean glucose after admission were associated with increased one-year mortality. CONCLUSION: In ST-segment-elevation MI patients treated with primary PCI, high-dose GIK induced hyperglycaemia and prevented hypokalaemia. Derangement of the glucose metabolism was related to one-year mortality.

The abdominal compartment syndrome: a complication with many faces.

BACKGROUND: Lately renewed attention has been given to the abdominal compartment syndrome. Despite of this there still remain a lot of controversies with regard to the pathophysiological mechanisms underlying this syndrome and the therapeutic options. METHODS: Two cases of patients with this syndrome are described and the data from animal and human trials concerning the abdominal compartment syndrome are presented and discussed. RESULTS: A variety of clinical disorders may lead to the abdominal compartment syndrome. It mainly affects the cardiovascular, pulmonary and renal organ systems. Although some clinical effects are clearly described, the exact mechanisms underlying these changes in humans are incompletely understood. It is still unclear why some patients develop abdominal compartment syndrome and others do not. The intra-abdominal pressure can easily be assessed by measuring the urine bladder pressure, which correlates well with the actual intra-abdominal pressure. All authors agree that a decompression of the abdomen by means of a laparotomy is the treatment of choice for the abdominal compartment syndrome. Which parameters should determine the indication however, remains controversial, since the correlation between clinical signs and pressure is not straightforward. CONCLUSIONS: The abdominal compartment syndrome is a well-recognised disease entity related to acutely increased abdominal pressure. Urgent laparotomy can be lifesaving in some cases. However no single threshold of abdominal pressure can be applied universally. Pending further clinical trials the best therapeutic option seems to be to decompress the abdomen surgically if the intravesical pressure is 25 mmHg or higher in patients with refractory hypotension, acute renal failure or respiratory failure due to abdominal distension.