Hyperammonaemia causing encephalopathy and coma is a recognized but rare cause of altered mental status in patients with urinary diversions, most commonly associated with ureterosigmoidostomy although also with ileal conduits. We describe the case of a 41-year-old lady with an ileal conduit who developed severe hyperchloraemic metabolic acidosis and associated hyperammonaemia. This led to a significant decrease in her Glasgow Coma Score such that she required Intensive Therapy Unit management. We review the current literature on this condition, discussing its aetiology and management.
A hypothetical elderly patient recovers from a cardiac arrest with very depressed consciousness, should he be admitted to intensive care? What are the factors involved in making the decision? A review of the published evidence, and a final conclusion.
Here we discuss the treatment of a post-lithotripsy, retroperitoneal haemorrhage using desmopressine (DDAVP) as monitored using closure time with a PFA-100 device. Five days after lithotripsy the patient's closure time reading (tested with the collagen plus epinephrine cartridge) normalized following DDAVP administration. This report demonstrates the usefulness of the PFA-100 in monitoring the treatment of platelet dysfunction and also evaluates possible contributory causes of this type of haemorrhage.
Background: Inhaled nitric oxide (NO) improves oxygenation in patients with acute respiratory distress syndrome (ARDS), and may act synergistically with high-frequency ventilation. High-frequency percussive ventilation (HFPV) has improved outcome in patients with inhalation injury. Thus, a system for NO delivery via HFPV would be desirable, but has not yet been described. Methods: A mechanical test lung was used for this evaluation. HFPV was delivered by means of a Volumetric Diffusive Respiration ventilator (VDR-4®). Spontaneous breaths were simulated by means of a lever arm attached to the bellows of the test lung. NO was instilled continuously at a constant rate into a side port between the sliding venturi of the VDR-4® and the endotracheal tube. Nitrogen dioxide (NO2) and NO levels were measured electrochemically via ports located at the front and back of the test lung. Expired gas was scavenged, and environmental NO2 levels were monitored. The ability of the system to provide constant NO levels, with NO2 levels less than 1 ppm, was evaluated across a full range of ventilator settings and NO concentrations. Results: Target NO concentrations were easily achieved at all ventilator settings, with the following exception. At a low-frequency rate of 8 breaths/min or less, increased variability in the NO concentration was observed at the front (but not at the back) sampling port. Also, at a low-frequency rate of 6 breaths/min or less, NO2 levels of 1.1–1.9 ppm were seen at the front sampling port only. Environmental levels of NO2 did not increase above baseline. Scavenging did not alter ventilator operation. Conclusions: Delivery of NO via HFPV can be safely performed within acceptable parameters, provided the low-frequency rate is greater than 6–8 breaths/min.
At a recent General Medical Council conference it was suggested by Dame Janet Smith, author of the Shipman inquiry report, that medical students should be assessed on their understanding of ethical principles (GMC Education Conference, May 9, 2005). Indeed, issues of medical ethics have recently made headline news around the world. In England, the right of a patient with progressive cerebellar ataxia to compel doctors to continued feeding for so long as he wishes is under appeal (Dyer, C. The Guardian, London, May 16th, 2005). In America, the recent death following withdrawal of feeding from Terri Schiavo, who was in a persistent vegetative state since 1990, taxed doctors, legislators and politicians up to the White House (Stolberg, SG, The New York Times, April 1, 2005). While such high profile cases arise exceptionally, critical care routinely involves ethical considerations, either implicitly or explicitly. This review describes various ethical principles commonly employed in relation to critical care, and the common problems with their application in the practice of managing the critically ill patient.
Objective. To evaluate the efficacy of a training program in pediatric intensive care for pediatric residents. Design. A prospective observational study. Setting. A pediatric intensive care unit. Interventions and measurements. A training program for residents in pediatrics. We performed an initial and final written theoretical test, an evaluation by the physician responsible for the program, a self-assessment by the residents, and a written survey on the quality of the training program. Results. Fifty-three pediatric residents were included in the training program. All residents showed improvement between the initial and final written theoretical tests [initial score 4.8±1.2, final score 8.3±0.8, p<0.001]. Only 7.5% of the residents answered correctly at least 70% of the questions in the initial theoretical test, compared with 94.1% in the final test [p<0.001]. The score in the final theoretical test, 8.3±0.8, was significantly higher than the residents’ self-evaluation, 6.7±0.9, and the evaluation by the tutor, 6.7±0.8 [p<0.001]. There were no differences between the residents’ self-evaluation of practical learning [6.2±1.0] and the evaluation of this by the tutor [6.5±0.9]. Residents considered the training program to be adequate [theoretical training 8.3±0.8, residents’ handbook 9±0.9, practical teaching 8.1±1.2, research 7.4±2.1, and human relationships 9.1±1]. Conclusions. This training program appears to be a useful educational method for theoretical and practical training in pediatric intensive care for the pediatric residents. The evaluation is essential to control the results of pediatric resident training.KeywordsEducationpediatric intensive carecurriculumpediatric critical care trainingpediatric residentsevaluation
(2006). Acquired tracheoesophageal fistula after prolonged mechanical ventilation. Clinical Intensive Care: Vol. 17, No. 1-2, pp. 51-54.
Pulmonary embolism is a life-threatening condition which has a number of clinical manifestations. We report a case of a 68-year old female who presented in cardiac arrest following an episode of chest pain. Admission electrocardiogram (ECG) demonstrated inferior ST elevation suggestive of acute myocardial infarction but prompt resolution of these changes cast doubt over the diagnosis. This was resolved by the use of urgent bedside trans-oesophageal echocardiography (TOE) which demonstrated multiple mobile costs in the right atrium and ventricle. A review of the literature on this condition and the use of TOE as an early diagnostic modality is discussed.
Cor triatriatum sinistrum (CTs) represents approximately 0.1% of congenital heart disease. The presence of an abnormal, often fenestrated fibromuscular membrane is indicative of CTs and results in a subdivided left atrium that can obstruct pulmonary venous return leading to elevated pulmonary venous and pulmonary artery pressures. We describe a case of CTs presenting well into adulthood with the unusual association of atrial flutter. Given the rarity of CTs, this unique observation with atrial flutter is limited to this case report, but is meant to illustrate the ramifications of this arrhythmia even in this relatively simple congenital heart defect, as our patient's arrhythmia was refractory to treatment and behaved similarly to atrial flutter observed among patients with more complex heart defects. Accurate diagnosis of the abnormal atrial membrane in the setting of other cardiac defects is imperative because pulmonary venous obstruction can occur after surgery for the associated defects. An associated atrial arrhythmia complicates management further and remains an important cause of morbidity and mortality in patients with congenital heart defects regardless of whether or not they have had corrective heart surgery. Atrial flutter is particularly worrisome since its onset is usually associated with clinical deterioration in adult patients with congenital heart defects. Physicians need to be cognizant of this increasing new cardiac patient population particularly after the typical causes of atrial flutter (e.g., ischemic disease, electrolyte disturbances, thyroid disease, and mitral valve disease, etc) have been ruled out.
Objective. Over 250,000 cases of central venous catheter-associated bloodstream infections (CVC-BSI) occur annually in the US leading to increased morbidity, costs, and mortality. While found to decrease the incidence of CVC-BSI in adult patients, no recommendations exist on the use of antimicrobial-impregnated catheters (AIC) in pediatric patients. This study was conducted to assess the effectiveness of AIC in reducing the incidence rates of CVC-BSI in a pediatric intensive care unit (PICU). Design. Retrospective cohort study. Setting. A 16-bed PICU in a tertiary children's hospital. Interventions and measurements. All PICU admissions requiring placement of a central venous catheter (CVC) from January 1999 through June 2003 were assessed for CVC-BSI, 21 months before, and 30 months after, introduction of AICs. Results. Of 5005 admissions during the 51-month study period, 1656 (33%) required CVC placement. Of these, 1441 (87%) admissions were initially assessed. Of these, 612 admissions (3057 CVC days) required CVC placement during the initial 21-month period while 829 admissions (4220 CVC days) required CVC placement during the subsequent 30-month period. The nosocomial CVC-BSI rates before and after the introduction of AICs were 7.85 CVC-BSI/1000 CVC days and 5.21 CVC-BSI/1000 CVC days, respectively (p=0.17). A sub-cohort of 647 (39%) admissions that required placement of a single CVC was subsequently analyzed. In the sub-cohort, 284 admissions (1269 CVC days) required CVC placement during the 21-month pre-AIC period, while 363 admissions (1458 CVC days) required CVC placement during the 30 months after introduction of AICs. The nosocomial CVC-BSI rates before and after the introduction of AICs were 3.15 CVC-BSI/1000 CVC days and 2.06 CVC-BSI/1000 CVC days, respectively (p=0.48). In multivariate regression analyses controlling for multiple risk factors for CVC-BSI, the use of AIC was not associated with statistically significant reduction in the rates of CVC-BSI among the entire cohort with multiple catheters (Incidence rate ratio = 1.04, 95% Confidence Interval: 0.93–1.15), or in the sub-cohort with single catheters (Incidence rate ratio = 0.91, 95% Confidence Interval: 0.78–1.06). Conclusions. Introduction of antimicrobial-impregnated catheters was associated with no significant reduction in nosocomial CVC-BSI rates in a cohort of critically ill children. Further adequately-powered prospective studies to address the effectiveness of AICs in reducing nosocomial CVC-BSI rates among cohorts of critically ill children are required.
Errors in intensive care units indicate a breakdown in the system or wrong decision-making. They must be recognized, their causes analyzed and preventive measures taken. We should try to understand the causes of errors, to install an informative reporting system of adverse events as an essential prerequisite, to measure them, and to choose the best approaches for minimizing the harm to the patients. Patient care, safety and quality must continue to be our highest priority. It is to be improved by our collective effort.
Atrioventricular conduction disturbances are uncommon as the first presentation of infective endocarditis (IE) and are often related to the extension of the valve infection around the annulus and a perivalvular abscess. The electrocardiogram can be useful in the diagnosis of IE. New onset atrioventricular conduction disturbances in a patient with a prosthetic valve, make the diagnosis of IE likely. We present a patient, with an aortic prosthesis, without any sign of sepsis, in whom a type I seconddegree atrioventricular block was the first clinical finding of IE. The patient was admitted for pacemaker implantation because of symptomatic atrioventricular block. Two days after admission, fever was present and Streptococcus viridans grew in blood cultures. An echocardiogram showed a vegetation on the prosthetic valve. In prosthetic valve carriers, echocardiography could be encouraged to preclude IE before pacemaker implant, even when signs or symptoms of sepsis are absent, avoiding electrode infection.
Objectives. Laparotomy in the elderly population is a frequently performed operation with high mortality. Little is published about the anaesthetic management of these patients. In view of this high mortality, such data would be useful prior to designing studies where the effect of interventions in peri-operative practice might be studied. Design. A postal survey of the proposed management of two hypothetical 75 year olds. Patient A: ASA 2, requiring elective anterior resection. Patient B: ASA 3 requiring emergency laparotomy for bowel obstruction. Setting. The survey was sent to the anaesthetic college tutor in 251 acute National Health Service hospitals in the UK, who was asked to pass it to the anaesthetist working in the emergency theatre on that day. Interventions and measurements. If no reply was received within 6 weeks, the survey was resent. Replies were analysed and the data summarized. Main results. Replies were received from 163 (65%) anaesthetists. Nineteen per cent of emergency lists were supervised by a non-consultant. Pre-operative ‘optimization’ (including, variously, administration of fluids, oxygen and vasoactive drugs) would have been carried out for patient A by 19% and for patient B by 91%, but this was never ‘goal-directed pre-optimization’. Invasive haemodynamic monitoring would have been used by two-thirds for patient A and universally for patient B. Conversely epidural techniques would have been used almost universally for patient A and by 71% for patient B, in whom the use of an epidural would also have been delayed until post-operatively more frequently. For 97%, anaesthetic maintenance would have included a volatile agent, for 33–45% nitrous oxide and for 10% remifentanil. There was evidence of wide variations in the tolerance of hypovolaemia and hypotension between anaesthetists, but not between patients. The initial management of these complications was generally with fluid administration but subsequent drug management varied considerably. Post-operatively, all respondents would have extubated patient A, half would have returned patient A to the wards and none to intensive care. For patient B, half would have extubated the patient and 87% would have transferred the patient to a critical care bed. Sixty per cent of respondents reported difficulty in accessing critical care beds. Conclusions. Laparotomy in the elderly is managed variably in the UK. This survey identifies considerable variation between anaesthetists in the management of these high-risk patients. It is likely that variations in management impact outcome. Knowledge of current practice has value in planning further rigorous studies of this subject.
Levomepromazine has been used as an adjunct to standard sedative therapies in mechanically ventilated ICU patients, despite a relative lack of safety data. This addition could increase the risk of cholestasis, a side effect common among phenothiazines. The aim of our study was to assess whether the addition of an infusion of levomepromazine to midazolam increases the risk of cholestasis. The index group was retrospectively defined by patients with an infusion of levomepromazine in addition to infusion of midazolam. The control group was retrospectively defined by patients with infusion of midazolam alone. Liver function tests were retrieved from patient data records. Exclusion criteria were serum AP, GGT, ALAT levels more than a 2-fold increase of the upper limit of normal value (ULN), on the first day of therapy. Drug-induced cholestatic liver injury was defined as more than a 2-fold increase from baseline of the ULN of alkaline phosphatase. No statistically significant differences were found for age, sex, duration of therapy and liver function tests between index and reference groups at the start of therapy. In the index group, midazolam infusion started 5.3±7.2 days before levomepromazine was added. Fourteen of 64 (21.9%) patients in the index group versus 32 of 270 (11.9%) in the reference group developed drug-induced cholestasis (p=0.029). No statistically significant co-variables were identified. We found that the addition of levomepromazine to midazolam was associated with a 10% increased incidence for developing acute cholestasis. Future research should include extensive risk-factor analysis.
Objective. To describe the impact of nesiritide on critically ill children in heart failure. Design. A retrospective chart review. Setting. Pediatric intensive care unit of a university-affiliated tertiary care hospital. Patients. Fourteen children in heart failure, secondary to dilated cardiomyopathy (n =4), rejection (n =6) and congenital heart disease (n =4), managed with nesiritide while receiving two or more diuretics, two or more vasoactive medications, or increasing vasoactive or diuretic medications during the 12 h prior to nesiritide initiation. Interventions. None. Measurements and main results. The mean arterial pressure, heart rate, and central venous pressure did not change significantly following the administration of nesiritide. Fluid balance and urine output demonstrated suggestive, but non-significant, improvements (p =0.13 and 0.1, respectively). One patient experienced an episode of hypotension leading to the discontinuation of nesiritide. No other adverse events were noted. Three of 14 patients exhibited increases in serum creatinine of more than 0.5 mg/dl, including two patients whose creatinine rose above 2 mg/dl or doubled from baseline. Nine of 14 (64%) patients survived to hospital discharge. Conclusion. Nesiritide is well tolerated in pediatric patients who require high-dose or escalating doses of vasoactive or diuretic medications. The use of nesiritide in this population is not associated with significant changes in hemodynamic parameters and may improve fluid mobilization. A prospective study is necessary to rigorously examine its efficacy and safety.
Objective. To determine whether urinary 8-hydroxy-2′-deoxyguanosine (8-OHdG) levels are altered in patients with septic shock and whether polymyxin B-immobilized fibre (PMX-F) haemoperfusion reduces the 8-OHdG level in these patients. Design and subjects. Twenty patients with septic shock and 20 age-matched healthy volunteers were included in the study. The septic shock patients were divided into two treatment groups: a PMX-F treatment group (n =12) and a non-PMX-F treatment group (n =8). Standard supportive care was continued without change during PMX-F haemoperfusion. Clinical markers, including plasma endotoxin, were measured before and after the first and the second PMX-F treatment and the following day. Urinary 8-OHdG levels were also examined before and after the first and the second PMX-F treatment (24 h pooled urine) and the following day. Results. Urinary 8-OHdG levels were significantly higher in septic shock patients (median 38.0 ng/mg creatinine; range 16.0–52.0 ng/mg creatinine) than in healthy volunteers (5.5 ng/mg creatinine; range 4.5–7.5 ng/mg creatinine) (p <0.01). Urinary 8-OHdG levels correlated significantly with plasma endotoxin levels (p <0.01), the Acute Physiology and Chronic Health Evaluation score (p <0.01) and the Sepsis-related Organ Failure Assessment score (p <0.01). PMX-F haemoperfusion reduced the plasma endotoxin and urinary 8-OHdG levels significantly after the first (p <0.01) and the second treatment (p <0.001) and the following day (p <0.001). However, these markers did not change significantly with non-PMX treatment. Conclusions. An increased urinary 8-OHdG level appears to be associated with septic shock, and PMX-F haemoperfusion is effective in reducing urinary 8-OHdG levels in patients with septic shock.
Objective. To evaluate risk factors for fat embolism syndrome (FES) in patients with multiple trauma. Design. Case–control study. Setting. Tertiary care university hospital, surgical intensive care unit. Patients. Sixty adults with multiple trauma, 30 of them with FES. Interventions. None. Measurements and main results. Patients were matched by gender, age (±5 years), injury severity score and date. Thirty patients were considered as the control group. Mortality was significantly higher in the FES group (p<0.001). FES was linked to anaemia (p<0.03), thrombocytopenia (p<0.01) and hypocholesterolaemia (p<0.05). Some characteristics of fracture were associated with a high risk of occurrence of FES: right side (p<0.02), displaced (p<0.05) and closed fracture (p<0.05). The timing of fixation did not statistically differ between the two groups, but orthopaedic treatment was linked with the occurrence of FES (p<0.005). In multivariate analysis, the Acute Physiology and Chronic Health Evaluation System II (APACHE II) score (odds ratio 18.51; 95% confidence interval 12.05–41.66), displaced (odds ratio 2.51; 95% confidence interval 1.20–20.05) and closed fracture (odds ratio 2.70; 95% confidence interval 1.59–8.92), were found to be independent predictors of the occurrence of FES (p<0.001 and p<0.05, respectively). Conclusion. The severity of the initial injury and the characteristic of the fracture were the most important factors linked to the occurrence of FES in multiple trauma patients.
Objective. Raised intra-abdominal pressure (IAP) has a number of significant adverse physiological effects and it is therefore important to know whether prone ventilation increases IAP. The aim of this study was to address this question. Design. An observational study was carried out to examine the effect of prone ventilation on IAP using a consecutive sample of 10 patients with acute respiratory distress syndrome undergoing mechanical ventilation in the prone position. Measurement of IAP supine (baseline) and hourly for 5 h after prone positioning was made. Setting. A teaching hospital 12-bed intensive care unit. Main results. The mean IAP supine was 14.5 mmHg and the mean initial IAP prone was 10.3 mmHg and then 11.4, 10.3, 9.9, 9.9 and 8.4 mmHg hourly thereafter. A time series regression analysis demonstrated a small but statistically significant fall in IAP. Conclusion. It can be concluded that prone ventilation does not increase IAP.KeywordsComplicationsintra-abdominal pressureprone ventilation
Objective. To study the prognostic significance of plasma lactate levels as a functional marker for tissue hypoxia on admission in non-immune travellers with imported Plasmodium falciparum malaria and non-P. falciparum malaria. Design. Cross-sectional, prospective, observational study. Setting. Harbour Hospital, Institute for Tropical Diseases, a national referral centre for tropical diseases. Patients. One hundred and twenty-two non-immune travellers with imported malaria (one patient with P. malariae, four with P. ovale, 20 with P. vivax, 83 with uncomplicated P. falciparum and 14 patients with severe, complicated P. falciparum infection). Measurements. Plasma lactate levels and standard laboratory evaluations on admission in relation to malaria species and criteria for severe malaria. Results. The plasma lactate levels on admission of those travellers who acquired a severe P. falciparum infection were higher than those with either uncomplicated P. falciparum malaria or travellers with non-P. falciparum infections. In the group of travellers with P. falciparum infection, an increased plasma lactate level >2.2 mmol/l had a sensitivity of 64%, a specificity of 89%, a positive predictive value of 50% and a negative predictive value of 94% for severe disease. Conclusions. A timely determination of plasma lactate on admission may assist in the clinical decision making of travellers with malaria who should be candidates for intensified monitoring and parenteral treatment.
