Outcome Prediction after Cardiac Arrest Treated with Hypothermia

Rationale: Clinical and electrophysiological prognostic markers of brain anoxia have been mostly evaluated in comatose survivors of out hospital cardiac arrest (OHCA) after standard resuscitation, but their predictive value in patients treated with mild induced hypothermia (IH) is unknown. The objective of this study was to identify a predictive score of independent clinical and electrophysiological variables in comatose OHCA survivors treated with IH, aiming at a maximal positive predictive value (PPV) and a high negative predictive value (NPV) for mortality. Methods: We prospectively studied consecutive adult comatose OHCA survivors from April 2006 to May 2009, treated with mild IH to 33-34_C for 24h at the intensive care unit of the Lausanne University Hospital, Switzerland. IH was applied using an external cooling method. As soon as subjects passively rewarmed (body temperature >35_C) they underwent EEG and SSEP recordings (off sedation), and were examined by experienced neurologists at least twice. Patients with status epilepticus were treated with AED for at least 24h. A multivariable logistic regression was performed to identify independent predictors of mortality at hospital discharge. These were used to formulate a predictive score. Results: 100 patients were studied; 61 died. Age, gender and OHCA etiology (cardiac vs. non-cardiac) did not differ among survivors and nonsurvivors. Cardiac arrest type (non-ventricular fibrillation vs. ventricular fibrillation), time to return of spontaneous circulation (ROSC) >25min, failure to recover all brainstem reflexes, extensor or no motor response to pain, myoclonus, presence of epileptiform discharges on EEG, EEG background unreactive to pain, and bilaterally absent N20 on SSEP, were all significantly associated with mortality. Absent N20 was the only variable showing no false positive results. Multivariable logistic regression identified four independent predictors (Table). These were used to construct the score, and its predictive values were calculated after a cut-off of 0-1 vs. 2-4 predictors. We found a PPV of 1.00 (95% CI: 0.93-1.00), a NPV of 0.81 (95% CI: 0.67-0.91) and an accuracy of 0.93 for mortality. Among 9 patients who were predicted to survive by the score but eventually died, only 1 had absent N20. Conclusions: Pending validation in a larger cohort, this simple score represents a promising tool to identify patients who will survive, and most subjects who will not, after OHCA and IH. Furthermore, while SSEP are 100% predictive of poor outcome but not available in most hospitals, this study identifies EEG background reactivity as an important predictor after OHCA. The score appears robust even without SSEP, suggesting that SSEP and other investigations (e.g., mismatch negativity, serum NSE) might be principally needed to enhance prognostication in the small subgroup of patients failing to improve despite a favorable score.

Le sevrage ultra-rapide sous anesthésie générale: l'expérience de l'Hôpital de St-Loup [Ultrafast opiate detoxification under general anesthesia: the St. Loup Hospital experience]

Rapid antagonist induction under anesthesia is a method that has been increasingly used to detoxify opiate addicts. These procedures are useful to reduce the duration and the discomfort of withdrawal. However, the high risk and the cost of these methods require randomized clinical trial to evaluate safety and clinical effectiveness. The University Substance Abuse Division of Lausanne and the Intensive Care Unit of the St-Loup Hospital work on a randomized clinical trial comparing anesthesia-assisted versus traditional clonidine detoxification combined with an additional psychosocial week. This paper describes the technique of anesthesia used in our study. Our clinical experience suggests that, integrating this technique in a multidisciplinary network, with a strong emphasis on post-anesthetic follow-up, is a viable and safe option in the treatment of opiate dependence.

Prospective determination of imipenem concentration of the plasma of critically-ill children

ABSTRACT Imipenem plasma-concentrations were measured in 19 critically-ill children (median 0.8 year, range 0.02-12.9 years). Wide inter-individual variations (2-4x at peak and >10x at through concentrations) resulted in unpredictable plasma-levels in several children. To avoid subtherapeutic drug levels we recommend at least 100 mg/kg/day of imipenem-cilastatin in critically-ill children requiring such therapy.

Nosocomial bloodstream infection and clinical sepsis

Primary bloodstream infection (BSI) is a leading, preventable infectious complication in critically ill patients and has a negative impact on patients' outcome. Surveillance definitions for primary BSI distinguish those that are microbiologically documented from those that are not. The latter is known as clinical sepsis, but information on its epidemiologic importance is limited. We analyzed prospective on-site surveillance data of nosocomial infections in a medical intensive care unit. Of the 113 episodes of primary BSI, 33 (29%) were microbiologically documented. The overall BSI infection rate was 19.8 episodes per 1,000 central-line days (confidence interval [CI] 95%, 16.1 to 23.6); the rate fell to 5.8 (CI 3.8 to 7.8) when only microbiologically documented episodes were considered. Exposure to vascular devices was similar in patients with clinical sepsis and patients with microbiologically documented BSI. We conclude that laboratory-based surveillance alone will underestimate the incidence of primary BSI and thus jeopardize benchmarking.

Feasibility of non-invasive pressure support ventilation in infants with respiratory failure after extubation: a pilot study.

OBJECTIVE: To evaluate the feasibility and effects of non-invasive pressure support ventilation (NIV) on the breathing pattern in infants developing respiratory failure after extubation. DESIGN: Prospective pilot clinical study; each patient served as their own control. SETTING: A nine-bed paediatric intensive care unit of a tertiary university hospital. PATIENTS: Six patients (median age 5 months, range 0.5-7 months; median weight 4.2 kg, range 3.8-5.1 kg) who developed respiratory failure after extubation. INTERVENTIONS: After a period of spontaneous breathing (SB), children who developed respiratory failure were treated with NIV. MEASUREMENTS AND RESULTS: Measurements included clinical dyspnoea score (DS), blood gases and oesophageal pressure recordings, which were analysed for respiratory rate (RR), oesophageal inspiratory pressure swing (dPes) and oesophageal pressure-time product (PTPes). All data were collected during both periods (SB and NIV). When comparing NIV with SB, DS was reduced by 44% (P < 0.001), RR by 32% (P < 0.001), dPes by 45% (P < 0.01) and PTPes by 57% (P < 0.001). A non-significant trend for decrease in PaCO(2) was observed. CONCLUSION: In these infants, non-invasive pressure support ventilation with turbine flow generator induced a reduction of breathing frequency, dPes and PTPes, indicating reduced load of the inspiratory muscles. NIV can be used with some benefits in infants with respiratory failure after extubation.

Pulse pressure variation-guided fluid therapy after cardiac surgery: A pilot before-and-after trial.

PURPOSE: The aim of this study is to study the feasibility, safety, and physiological effects of pulse pressure variation (PPV)-guided fluid therapy in patients after cardiac surgery. MATERIALS AND METHODS: We conducted a pilot prospective before-and-after study during mandatory ventilation after cardiac surgery in a tertiary intensive care unit. We introduced a protocol to deliver a fluid bolus for a PPV ≥13% for at least >10 minutes during the intervention period. RESULTS: We studied 45 control patients and 53 intervention patients. During the intervention period, clinicians administered a fluid bolus on 79% of the defined PPV trigger episodes. Median total fluid intake was similar between 2 groups during mandatory ventilation (1297 mL [interquartile range 549-1968] vs 1481 mL [807-2563]; P = .17) and the first 24 hours (3046 mL [interquartile range 2317-3982] vs 3017 mL [2192-4028]; P = .73). After adjusting for several baseline factors, PPV-guided fluid management significantly increased fluid intake during mandatory ventilation (P = .004) but not during the first 24 hours (P = .47). Pulse pressure variation-guided fluid therapy, however, did not significantly affect hemodynamic, renal, and metabolic variables. No serious adverse events were noted. CONCLUSIONS: Pulse pressure variation-guided fluid management was feasible and safe during mandatory ventilation after cardiac surgery. However, its advantages may be clinically small.

Introducing a nationwide registry: the Swiss study on aneurysmal subarachnoid haemorrhage (Swiss SOS).

BACKGROUND: Aneurysmal subarachnoid haemorrhage (aSAH) is a haemorrhagic form of stroke and occurs in a younger population compared with ischaemic stroke or intracerebral haemorrhage. It accounts for a large proportion of productive life-years lost to stroke. Its surgical and medical treatment represents a multidisciplinary effort. Due to the complexity of the disease, the management remains difficult to standardise and quality of care is accordingly difficult to assess. OBJECTIVE: To create a registry to assess management parameters of patients treated for aSAH in Switzerland. METHODS: A cohort study was initiated with the aim to record characteristics of patients admitted with aSAH, starting January 1st 2009. Ethical committee approval was obtained or is pending from the institutional review boards of all centres. In the study period, seven Swiss hospitals (five university [U], two non-university medical centres) harbouring a neurosurgery department, an intensive care unit and an interventional neuroradiology team so far agreed to participate in the registry (Aarau, Basel [U], Bern [U], Geneva [U], Lausanne [U], St. Gallen, Zürich [U]). Demographic and clinical parameters are entered into a common database. DISCUSSION: This database will soon provide (1) a nationwide assessment of the current standard of care and (2) the outcomes for patients suffering from aSAH in Switzerland. Based on data from this registry, we can conduct cohort comparisons or design diagnostic or therapeutic studies on a national level. Moreover, a standardised registration system will allow healthcare providers to assess the quality of care.

Neuromonitoring after major neurosurgical procedures.

Postoperative care of major neurosurgical procedures is aimed at the prevention, detection and treatment of secondary brain injury. This consists of a series of pathological events (i.e. brain edema and intracranial hypertension, cerebral hypoxia/ischemia, brain energy dysfunction, non-convulsive seizures) that occur early after the initial insult and surgical intervention and may add further burden to primary brain injury and thus impact functional recovery. Management of secondary brain injury requires specialized neuroscience intensive care units (ICU) and continuous advanced monitoring of brain physiology. Monitoring of intracranial pressure (ICP) is a mainstay of care and is recommended by international guidelines. However, ICP monitoring alone may be insufficient to detect all episodes of secondary brain insults. Additional invasive (i.e. brain tissue PO2, cerebral microdialysis, regional cerebral blood flow) and non-invasive (i.e. transcranial doppler, near-infrared spectroscopy, EEG) brain monitoring devices might complement ICP monitoring and help clinicians to target therapeutic interventions (e.g. management of cerebral perfusion pressure, blood transfusion, glucose control) to patient-specific pathophysiology. Several independent studies demonstrate such multimodal approach may optimize patient care after major neurosurgical procedures. The aim of this review is to evaluate some of the available monitoring systems and summarize recent important data showing the clinical utility of multimodal neuromonitoring for the management of main acute neurosurgical conditions, including traumatic brain injury, subarachnoid hemorrhage and stroke.

Mechanical ventilation in the newborn; a simplified approach. Part 1: Intermittent positive pressure ventilation.

Positive pressure ventilation (PPV) is a frequent intervention in the neonatal intensive care unit. This article is directed towards paediatricians in training and attempts to cover the basics of PPV without being too technical. To do so we have employed an extensive use of graphics to illustrate the underlying principles.

Inefficacité de la gestion de l'hyperglycémie du patient hospitalisé: origines et remèdes [The inefficacy of glycemic control in the hospitalized patient: origins and solutions]

La prévalence du diabète peut être estimée entre 20 et 30% parmi les patients en hôpital aigu. Il a été démontré que l'hyperglycémie, même modérée, est associée à une augmentation de la morbi-mortalité hospitalière, tandis que le contrôle glycémique efficace a un impact favorable sur celle-ci. La prise en charge de l'hyperglycémie demeure pourtant largement inefficace hors des soins intensifs, en raison de la persistance d'une pratique inadaptée. Nous développons actuellement un projet de soins destiné à faire changer les pratiques. Pour un contrôle glycémique efficace, une formation des soignants à une gestion basée sur le concept de couverture des besoins en insuline du patient est nécessaire. La démarche doit être intégrée à une approche de type systémique, prenant en compte le contexte dans lequel les soignants évoluent. The hospital inpatient prevalence of diabetes mellitus can be estimated between 20 and 30%. Even moderate hyperglycemia is associated with increased morbidity and mortality in the acute care setting, whereas efficient glycemic control has been shown to improve both of them significantly. Glycemic control however remains largely inefficient outside of the intensive care unit due to the persistance of an inadequate glycemic management practice. We are currently developing a clinical care project aimed at changing this practice. For an efficient glycemic control, a training programme for health care professionals based on the concept of covering the insulin needs of the patient is mandatory. This programme needs to be integrated in a systemic approach, which takes the professionals' context in account.

Pediatric emergencies admitted in the resuscitation room of a Swiss university hospital.

OBJECTIVES: Pediatric resuscitation is an intense, stressful, and challenging process. The aim of this study was to review the life-threatening pediatric (LTP) emergencies admitted in a Swiss university hospital with regards to patients' demographics, reason for admission, diagnosis, treatment, significant events, critical incidents, and outcomes. METHODS: A retrospective observational cohort study of prospectively collected data was conducted, including all LTP emergencies admitted over a period of 2 years in the resuscitation room (RR). Variables, including indication for transfer, mode of prehospital transportation, diagnosis, and time spent in RR, were recorded. RESULTS: Of the 60,939 pediatric emergencies treated in our university hospital over 2 years, a total of 277 LTP emergencies (0.46%) were admitted in the RR. They included 160 boys and 117 girls, aged 6 days to 15.95 years (mean, 6.69 years; median, 5.06). A medical problem was identified in 55.9% (n = 155) of the children. Of the 122 children treated for a surgical problem, 35 (28.3%) went directly from the RR to the operating room. Hemodynamic instability was noted in 19.5% of all LTP emergencies, of which 1.1% benefited from O negative transfusion. Admission to the intensive care unit was necessary for 61.6% of the children transferred from another hospital. The average time spent in the RR was 46 minutes. The overall mortality rate was 7.2%. CONCLUSIONS: The LTP emergencies accounted for a small proportion of all pediatric emergencies. They were more medical than surgical cases and resuscitation measures because of hemodynamic instability were the most frequent treatment.

Isolated limb perfusion: distinct tourniquet and tumor necrosis factor effects on the early hemodynamic response.

HYPOTHESIS: Recent evidence indicates that tumor response rates after isolated limb perfusion (ILP) are improved when tumor necrosis factor (TNF) is added to the locoregional perfusion of high doses of chemotherapy. Other factors, related to the patient or the ILP procedure, may interfere with the specific role of TNF in the early hemodynamic response after ILP with TNF and high-dose chemotherapy. DESIGN: Case-control study. SETTING: Tertiary care university hospital. PATIENTS: Thirty-eight patients with a locoregionally advanced tumor of a limb treated by ILP with TNF and high-dose chemotherapy (TNF group) were compared with 31 similar patients treated by ILP with high-dose chemotherapy alone (non-TNF group). INTERVENTIONS: Swan-Ganz catheter hemodynamic recordings, patients' treatment data collection, and TNF and interleukin 6 plasma level measurements at regular intervals during the first 36 hours following ILP. MAIN OUTCOME MEASURES: Hemodynamic profile and total fluid and catecholamine administration. RESULTS: In the TNF group, significant changes were observed (P<.006): the mean arterial pressure and the systemic vascular resistance index decreased, and the temperature, heart rate, and cardiac index increased. These hemodynamic alterations started when the ILP tourniquet was released (ie, when or shortly after the systemic TNF levels were the highest). The minimal mean arterial pressure, the minimal systemic vascular resistance index, the maximal cardiac index, the intensive care unit stay, and the interleukin 6 maximal systemic levels were significantly (P<.001 for all) correlated to the log(10) of the systemic TNF level. In the non-TNF group, only a brief decrease in the blood pressure following tourniquet release and an increase in the temperature and in the heart rate were statistically significant (P<.006). Despite significantly more fluid and catecholamine administration in the TNF group, the mean arterial pressure and the systemic vascular resistance index were significantly (P<.001) lower than in the non-TNF group. CONCLUSIONS: Release of the tourniquet induces a blood pressure decrease that lasts less than 1 hour in the absence of TNF and that is distinct from the septic shock-like hemodynamic profile following TNF administration. The systemic TNF levels are correlated to this hemodynamic response, which can be observed even at low TNF levels.

Misleading tacrolimus concentration value in blood taken from a catheter used for tacrolimus administration.

PURPOSE: A misleading blood tacrolimus concentration (BTC) value caused by the contamination of a central venous catheter previously used for tacrolimus administration is described. SUMMARY: A 59-year-old woman with severe chronic obstructive pulmonary disease successfully underwent double lung transplantation. In the intensive care unit, she received a continuous i.v. infusion of tacrolimus from days 1 to 5 after transplantation through the distal lumen of a polyurethane triple-lumen central venous catheter. The catheter lumen was flushed twice a day with 0.9% sodium chloride injection. The proximal lumen was used for blood sampling after being flushed; the first 10 mL of blood was discarded. BTCs determined in whole blood one, four, and five days after transplantation were within the therapeutic range of 5-15 ng/mL. On day five the patient was transferred to the thoracic surgery ward and was switched to oral tacrolimus 1.5 mg twice daily. The BTC on day 6 was unexpectedly high at 134.5 ng/mL. The patient's clinical status was normal, and no signs of tacrolimus toxicity were observed. On day 7, blood samples were drawn from a peripheral vein and simultaneously through the central venous catheter. Although the central venous catheter had not been exposed to tacrolimus during the preceding two days, it yielded blood with a BTC eight times higher than the BTC in blood from the peripheral vein (41.4 ng/mL versus 5.1 ng/mL). CONCLUSION: The collection of blood from a central venous catheter lumen that had been used for tacrolimus administration resulted in a BTC about eight times higher than what was measured in peripheral blood.

Monitoring the clinical introduction of a glutamine and antioxidant solution in critically ill trauma and burn patients

OBJECTIVE: Enteral glutamine supplementation and antioxidants have been shown to be beneficial in some categories of critically ill patients. This study investigated the impact on organ function and clinical outcome of an enteral solution enriched with glutamine and antioxidant micronutrients in patients with trauma and with burns. METHODS: This was a prospective study of a historical control group including critically ill, burned and major trauma patients (n = 86, 40 patients with burns and 46 with trauma, 43 in each group) on admission to an intensive care unit in a university hospital (matching for severity, age, and sex). The intervention aimed to deliver a 500-mL enteral solution containing 30 g of glutamine per day, selenium, zinc, and vitamin E (Gln-AOX) for a maximum of 10 d, in addition to control treatment consisting of enteral nutrition in all patients and intravenous trace elements in all burn patients. RESULTS: Patients were comparable at baseline, except for more inhalation injuries in the burn-Gln-AOX group (P = 0.10) and greater neurologic impairment in the trauma-Gln-AOX group (P = 0.022). Intestinal tolerance was good. The full 500-mL dose was rarely delivered, resulting in a low mean glutamine daily dose (22 g for burn patients and 16 g for trauma patients). In burn patients intravenous trace element delivery was superior to the enteral dose. The evolution of the Sequential Organ Failure Assessment score and other outcome variables did not differ significantly between groups. C-reactive protein decreased faster in the Gln-AOX group. CONCLUSION: The Gln-AOX supplement was well tolerated in critically ill, injured patients, but did not improve outcome significantly. The delivery of glutamine below the 0.5-g/kg recommended dose in association with high intravenous trace element substitution doses in burn patients are likely to have blunted the impact by not reaching an efficient treatment dose. Further trials testing higher doses of Gln are required.

Impact of tight glycemic control on cerebral glucose metabolism after severe brain injury: a microdialysis study.

OBJECTIVES: To analyze the effect of tight glycemic control with the use of intensive insulin therapy on cerebral glucose metabolism in patients with severe brain injury. DESIGN: Retrospective analysis of a prospective observational cohort. SETTING: University hospital neurologic intensive care unit. PATIENTS: Twenty patients (median age 59 yrs) monitored with cerebral microdialysis as part of their clinical care. INTERVENTIONS: Intensive insulin therapy (systemic glucose target: 4.4-6.7 mmol/L [80-120 mg/dL]). MEASUREMENTS AND MAIN RESULTS: Brain tissue markers of glucose metabolism (cerebral microdialysis glucose and lactate/pyruvate ratio) and systemic glucose were collected hourly. Systemic glucose levels were categorized as within the target "tight" (4.4-6.7 mmol/L [80-120 mg/dL]) vs. "intermediate" (6.8-10.0 mmol/L [121-180 mg/dL]) range. Brain energy crisis was defined as a cerebral microdialysis glucose <0.7 mmol/L with a lactate/pyruvate ratio >40. We analyzed 2131 cerebral microdialysis samples: tight systemic glucose levels were associated with a greater prevalence of low cerebral microdialysis glucose (65% vs. 36%, p < 0.01) and brain energy crisis (25% vs.17%, p < 0.01) than intermediate levels. Using multivariable analysis, and adjusting for intracranial pressure and cerebral perfusion pressure, systemic glucose concentration (adjusted odds ratio 1.23, 95% confidence interval [CI] 1.10-1.37, for each 1 mmol/L decrease, p < 0.001) and insulin dose (adjusted odds ratio 1.10, 95% CI 1.04-1.17, for each 1 U/hr increase, p = 0.02) independently predicted brain energy crisis. Cerebral microdialysis glucose was lower in nonsurvivors than in survivors (0.46 +/- 0.23 vs. 1.04 +/- 0.56 mmol/L, p < 0.05). Brain energy crisis was associated with increased mortality at hospital discharge (adjusted odds ratio 7.36, 95% CI 1.37-39.51, p = 0.02). CONCLUSIONS: In patients with severe brain injury, tight systemic glucose control is associated with reduced cerebral extracellular glucose availability and increased prevalence of brain energy crisis, which in turn correlates with increased mortality. Intensive insulin therapy may impair cerebral glucose metabolism after severe brain injury.