Monocentric, Retrospective Study on Infectious Complications within One Year after Solid-Organ Transplantation at a Belgian University Hospital

The epidemiology, diagnostic methods and management of infectious complications after solid-organ transplantation (SOT) are evolving. The aim of our study is to describe current infectious complications in the year following SOT and risk factors for their development and outcome. We conducted a retrospective study in adult SOT recipients in a Belgian university hospital between 2018 and 2019. We gathered demographic characteristics, comorbidities leading to transplantation, clinical, microbiological, surgery-specific and therapeutic data concerning infectious episodes, and survival status up to one year post-transplantation. Two-hundred-and-thirty-one SOT recipients were included (90 kidneys, 79 livers, 35 lungs, 19 hearts and 8 multiple organs). We observed 381 infections in 143 (62%) patients, due to bacteria (235 (62%)), viruses (67 (18%)), and fungi (32 (8%)). Patients presented a median of two (1-5) infections, and the first infection occurred during the first six months. Nineteen (8%) patients died, eleven (58%) due to infectious causes. Protective factors identified against developing infection were obesity [OR [IC]: 0.41 [0.19-0.89]; p = 0.025] and liver transplantation [OR [IC]: 0.21 [0.07-0.66]; p = 0.007]. Risk factors identified for developing an infection were lung transplantation [OR [IC]: 6.80 [1.17-39.36]; p = 0.032], CMV mismatch [OR [IC]: 3.53 [1.45-8.64]; p = 0.006] and neutropenia [OR [IC]: 2.87 [1.27-6.47]; p = 0.011]. Risk factors identified for death were inadequate cytomegalovirus prophylaxis, infection severity and absence of pneumococcal vaccination. Post-transplant infections were common. Addressing modifiable risk factors is crucial, such as pneumococcal vaccination.

The effect of increased positive end expiratory pressure on brain tissue oxygenation and intracranial pressure in acute brain injury patients

Cerebral hypoxia is an important cause of secondary brain injury. Improving systemic oxygenation may increase brain tissue oxygenation (PbtO2). The effects of increased positive end-expiratory pressure (PEEP) on PbtO2 and intracranial pressure (ICP) needs to be further elucidated. This is a single center retrospective cohort study (2016-2021) conducted in a 34-bed Department of Intensive Care unit. All patients with acute brain injury under mechanical ventilation who were monitored with intracranial pressure and brain tissue oxygenation (PbtO2) catheters and underwent at least one PEEP increment were included in the study. Primary outcome was the rate of PbtO2 responders (increase in PbtO2 > 20% of baseline) after PEEP increase. ΔPEEP was defined as the difference between PEEP at 1 h and PEEP at baseline; similarly ΔPbtO2 was defined as the difference between PbtO2 at 1 h after PEEP incrementation and PbtO2 at baseline. We included 112 patients who underwent 295 episodes of PEEP increase. Overall, the median PEEP increased form 6 (IQR 5-8) to 10 (IQR 8-12) cmH2O (p = 0.001), the median PbtO2 increased from 21 (IQR 16-29) mmHg to 23 (IQR 18-30) mmHg (p = 0.001), while ICP remained unchanged [from 12 (7-18) mmHg to 12 (7-17) mmHg; p = 0.42]. Of 163 episode of PEEP increments with concomitant PbtO2 monitoring, 34 (21%) were PbtO2 responders. A lower baseline PbtO2 (OR 0.83 [0.73-0.96)]) was associated with the probability of being responder. ICP increased in 142/295 episodes of PEEP increments (58%); no baseline variable was able to identify this response. In PbtO2 responders there was a moderate positive correlation between ΔPbtO2 and ΔPEEP (r = 0.459 [95% CI 0.133-0.696]. The response in PbtO2 and ICP to PEEP elevations in brain injury patients is highly variable. Lower PbtO2 values at baseline could predict a significant increase in brain oxygenation after PEEP increase.

Safety and Effectiveness of Carbon Dioxide Removal CO2RESET Device in Critically Ill Patients

BACKGROUND

In this retrospective study, we report the effectiveness and safety of a dedicated extracorporeal carbon dioxide removal (ECCO₂R) device in critically ill patients.

METHODS

Adult patients on mechanical ventilation due to acute respiratory distress syndrome (ARDS) or decompensated chronic obstructive pulmonary disease (dCOPD), who were treated with a dedicated ECCO₂R device (CO2RESET, Eurosets, Medolla, Italy) in case of hypercapnic acidemia, were included. Repeated measurements of CO₂ removal (VCO₂) at baseline and 1, 12, and 24 h after the initiation of therapy were recorded.

RESULTS

Over a three-year period, 11 patients received ECCO₂R (median age 60 [43-72] years) 3 (2-39) days after ICU admission; nine patients had ARDS and two had dCOPD. Median baseline pH and PaCO₂ levels were 7.27 (7.12-7.33) and 65 (50-84) mmHg, respectively. With a median ECCO₂R blood flow of 800 (500-800) mL/min and maximum gas flow of 6 (2-14) L/min, the VCO₂ at 12 h after ECCO₂R initiation was 157 (58-183) mL/min. Tidal volume, respiratory rate, and driving pressure were significantly reduced over time. Few side effects were reported.

CONCLUSIONS

In this study, a dedicated ECCO₂R device provided a high VCO₂ with a favorable risk profile.

In-hospital and 6-month outcomes in patients with COVID-19 supported with extracorporeal membrane oxygenation (EuroECMO-COVID): a multicentre, prospective observational study

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) has been widely used in patients with COVID-19, but uncertainty remains about the determinants of in-hospital mortality and data on post-discharge outcomes are scarce. The aims of this study were to investigate the variables associated with in-hospital outcomes in patients who received ECMO during the first wave of COVID-19 and to describe the status of patients 6 months after ECMO initiation.

METHODS

EuroECMO-COVID is a prospective, multicentre, observational study developed by the European Extracorporeal Life Support Organization. This study was based on data from patients aged 16 years or older who received ECMO support for refractory COVID-19 during the first wave of the pandemic-from March 1 to Sept 13, 2020-at 133 centres in 21 countries. In-hospital mortality and mortality 6 months after ECMO initiation were the primary outcomes. Mixed-Cox proportional hazards models were used to investigate associations between patient and management-related variables (eg, patient demographics, comorbidities, pre-ECMO status, and ECMO characteristics and complications) and in-hospital deaths. Survival status at 6 months was established through patient contact or institutional charts review. This study is registered with ClinicalTrials.gov, NCT04366921, and is ongoing.

FINDINGS

Between March 1 and Sept 13, 2020, 1215 patients (942 [78%] men and 267 [22%] women; median age 53 years [IQR 46-60]) were included in the study. Median ECMO duration was 15 days (IQR 8-27). 602 (50%) of 1215 patients died in hospital, and 852 (74%) patients had at least one complication. Multiorgan failure was the leading cause of death (192 [36%] of 528 patients who died with available data). In mixed-Cox analyses, age of 60 years or older, use of inotropes and vasopressors before ECMO initiation, chronic renal failure, and time from intubation to ECMO initiation of 4 days or more were associated with higher in-hospital mortality. 613 patients did not die in hospital, and 547 (95%) of 577 patients for whom data were available were alive at 6 months. 102 (24%) of 431 patients had returned to full-time work at 6 months, and 57 (13%) of 428 patients had returned to part-time work. At 6 months, respiratory rehabilitation was required in 88 (17%) of 522 patients with available data, and the most common residual symptoms included dyspnoea (185 [35%] of 523 patients) and cardiac (52 [10%] of 514 patients) or neurocognitive (66 [13%] of 512 patients) symptoms.

INTERPRETATION

Patient's age, timing of cannulation (<4 days vs ≥4 days from intubation), and use of inotropes and vasopressors are essential factors to consider when analysing the outcomes of patients receiving ECMO for COVID-19. Despite post-discharge survival being favourable, persisting long-term symptoms suggest that dedicated post-ECMO follow-up programmes are required.

FUNDING

None.

Veno-arterial CO2 difference and respiratory quotient after cardiac arrest: An observational cohort study

PURPOSE

To characterize venous-arterial CO₂ difference (ΔpCO₂) and the respiratory quotient (RQ) in post cardiac arrest patients and evaluate the association between these parameters and patient outcome.

MATERIALS AND METHODS

Data were obtained retrospectively from post cardiac arrest patients admitted between 2007 and 2016 to a medical intensive care unit. Comatose, adult patients in whom arterial and venous blood gas analyses were concomitantly performed in the first 24 h were included. Patients were grouped according to the time-point of sampling; 0-6, 6-12 and 12-24 h after admission.

RESULTS

308 patients were included; 174 (56%) died before ICU discharge and 212 (69%) had an unfavorable neurologic outcome. RQ was associated with ICU mortality (OR:1.09 (95%CI: 1.04-1.14; p < 0.01)), although not with neurological outcome. ΔpCO₂ was negatively associated with both ICU mortality (OR: 0.92 (95%CI: 0.86-0.99; p = 0.02)) and poor neurologic outcome (adjusted OR: 0.93 (95%CI: 0.87-0.99; p = 0.02)). ΔpCO₂ predicted an elevated RQ; a ΔpCO₂ above 8.5 mmHg identified a high RQ with reasonable sensitivity and specificity.

CONCLUSIONS

RQ was associated with ICU mortality and ΔpCO₂ identified elevated RQ in the early phase after cardiac arrest. However, ΔpCO₂ were negatively associated with both ICU mortality and neurologic outcome.

Low hemoglobin and venous saturation levels are associated with poor neurological outcomes after cardiac arrest

INTRODUCTION

Hemoglobin (Hb) is a main determinant of tissue oxygen delivery and anemia could be particularly harmful in post-anoxic brain injury. The aim of this study was to evaluate the association of Hb and venous Hb oxygen saturation (SvO₂/ScvO₂) with long-term neurological outcome in patients admitted after cardiac arrest (CA).

METHODS

Analysis of adult CA patients admitted to the Department of Intensive Care of the Erasme University Hospital (Brussels, Belgium) over 9 years. We retrieved all data concerning CA characteristics as well as Hb during the first 48 h since injury as well as the need for red blood cells transfusions (RBCT). Minimum Hb and Hb oxygen saturation values were recorded. Neurological outcome was evaluated 3 months after CA. Unfavorable neurological outcome (UO) was defined as a Cerebral Performance Categories (CPC) score of 3-5.

RESULTS

We treated 414 patients patients with CA, including 231 (56%) out-of-hospital cardiac arrest (OHCA) and 158 (38%) with an initial shockable rhythm. Median Hb concentration on admission was 12.0 [9.9-13.7] g/dL and the lowest Hb concentration was 10.0 [8.1-11.0] g/dL; 127 patients (31%) received at least one RBCT. Hb oxygen saturation on admission was 67 [59-74]%, while the lowest value was 60 [53-68]%. Low Hb and Hb oxygen saturation values were independently associated with UO; the optimal cut-off to predict UO was <9.9 g/dL and <60%, respectively.

CONCLUSIONS

Low hemoglobin values and low values of oxygen venous saturation are significantly associated with unfavorable neurological outcome in adult patients resuscitated from cardiac arrest.

A practical approach to the use of targeted temperature management after cardiac arrest

Among comatose survivors after cardiac arrest, target temperature management (TTM) is considered the most effective treatment to reduce the consequences of postanoxic brain injury. Several international guidelines have thus incorporated TTM in the management of the postresuscitation phase. However, despite extremely promising results in animal models and in randomized trials including selected patient cohorts, TTM benefits on neurological outcome have been questioned. Moreover, TTM potential side effects have raised some concerns on its wide application in all cardiac arrest patients in different healthcare systems. There is indeed still relatively large uncertainty concerning some practical aspects related to TTM application, such as: A) how to select patients who will benefit the most from TTM; B) the optimal time to initiate TTM; C) the best target temperature; D) the most effective methods to provide TTM; E) the length of the cooling phase; and F) the optimal rewarming rate and fever control strategies. The purpose of this manuscript is to review and discuss the most recent advances in TTM use after cardiac arrest and to give some proposals on how to deal with all these relevant practical questions.

Gastrointestinal dysfunction in the critically ill: a systematic scoping review and research agenda proposed by the Section of Metabolism, Endocrinology and Nutrition of the European Society of Intensive Care Medicine

BACKGROUND

Gastrointestinal (GI) dysfunction is frequent in the critically ill but can be overlooked as a result of the lack of standardization of the diagnostic and therapeutic approaches. We aimed to develop a research agenda for GI dysfunction for future research. We systematically reviewed the current knowledge on a broad range of subtopics from a specific viewpoint of GI dysfunction, highlighting the remaining areas of uncertainty and suggesting future studies.

METHODS

This systematic scoping review and research agenda was conducted following successive steps: (1) identify clinically important subtopics within the field of GI function which warrant further research; (2) systematically review the literature for each subtopic using PubMed, CENTRAL and Cochrane Database of Systematic Reviews; (3) summarize evidence for each subtopic; (4) identify areas of uncertainty; (5) formulate and refine study proposals that address these subtopics; and (6) prioritize study proposals via sequential voting rounds.

RESULTS

Five major themes were identified: (1) monitoring, (2) associations between GI function and outcome, (3) GI function and nutrition, (4) management of GI dysfunction and (5) pathophysiological mechanisms. Searches on 17 subtopics were performed and evidence summarized. Several areas of uncertainty were identified, six of them needing consensus process. Study proposals ranked among the first ten included: prevention and management of diarrhoea; management of upper and lower feeding intolerance, including indications for post-pyloric feeding and opioid antagonists; acute gastrointestinal injury grading as a bedside tool; the role of intra-abdominal hypertension in the development and monitoring of GI dysfunction and in the development of non-occlusive mesenteric ischaemia; and the effect of proton pump inhibitors on the microbiome in critical illness.

CONCLUSIONS

Current evidence on GI dysfunction is scarce, partially due to the lack of precise definitions. The use of core sets of monitoring and outcomes are required to improve the consistency of future studies. We propose several areas for consensus process and outline future study projects.

The characteristics of patients with bilateral absent evoked potentials after post-anoxic brain damage: A multicentric cohort study

OBJECTIVES

Patients with bilateral absence of cortical response (N20_ABS) to somatosensory evoked potentials (SSEPs) have poor neurological outcome after cardiac arrest (CA). However, SSEPs are not available in all centers. The aim of this study was to identify predictors of N20_ABS.

METHODS

Retrospective analysis of institutional databases (2008-2015) in three ICUs including all adult admitted comatose patients undergoing SSEPs between 48 and 72 h after CA. We collected clinical (i.e. absence of pupillary reflexes, PLR, myoclonus and absent or posturing motor response and myoclonus on day 2-3), electroencephalographic (EEG; i.e. unreactive to painful stimuli; presence of a highly malignant patterns, such as burst-suppression or flat tracings) findings during the first 48 h, and the highest NSE levels on the first 3 days after CA. Unfavorable neurological outcome (UO) was assessed at 3 months using the Cerebral Performance Categories of 3-5.

RESULTS

We studied 532 patients with SSEPs, including 143 (27%) without N20_ABS; UO was observed in 334 (63%) patients. Median time to SSEPs was 72 [48-72] h after CA. No patient with absent PLR and myoclonus during the ICU stay had N20 present; similar results were observed with the combination of absent PLR, myoclonus and any EEG pattern (i.e. unreactive or highly malignant). Similar results were observed in the subgroup of patients where NSE was available (n = 303). In a multivariate logistic regression, non-cardiac etiology of arrest, unreactive EEG to painful stimuli, absence of pupillary reflexes and posturing motor response, were independent predictors of N20_ABS. When available, the highest NSE was also an independent predictor of N20_ABS.

CONCLUSIONS

Clinical and EEG findings predicting patients with N20_ABS, confirm that N20_ABS reflects a severe and permanent cerebral damage after CA.

Doctor-patient communication tricks. Oncological study at Campus Bio-Medico University of Rome

OBJECTIVE

Doctor-patient relationship is a very important variable in the oncological clinical consultation.

METHODS

We have analyzed 100 outpatients oncological visits (first visits and follow up visits). We conducted an observational study of the extra verbal communication (non-verbal and para-verbal) with a structured observation grid. We have analyzed the three stages of the visit: 1. Patient's admission, 2. Communication flows and 3. Information exchange between doctor and patient.

RESULT

In the first visit doctor introduce himself (85%). In the follow-up visit the doctor has received the patient with a handshake (86%) while in the first examination in 100%. In the follow-up visit the short phase of pleasantries was present in 61% of cases, while in the first examination in 45% of cases. Doctor drawn an outline, a design or wrote a note in 45% of first examination and 25% of the follow up.

CONCLUSION

Extra verbal communication is more important than the verbal. We suggest useful tips on what "do not" and what "do better" during clinical consultations.

CONCLUSION

Against what it is often believed eye contact is not always necessary or useful in establishing a good doctor-patient relationship it depends on the patient's preferred representational system.

Can red blood cell distribution width predict outcome after cardiac arrest?

BACKGROUND

In critically ill patients, high red blood cell distribution width (RDW) values have been associated with increased hospital mortality, but there are no data on the impact of RDW on outcomes of patients resuscitated from cardiac arrest (CA). The aim of this study was to investigate the relationship between RDW and long-term neurologic outcome in CA survivors.

METHODS

We performed a retrospective analysis of an institutional database including all unconscious adult patients admitted to the intensive care unit (ICU) after non-traumatic CA between January 2007 and January 2015. Patients who survived <24 hours were excluded. The RDW (normal values 10.9-13.4%) was obtained daily from the day of admission to day 3. Patients with a cerebral performance category (CPC) score of 3-5 at 3 months were considered to have an unfavourable neurological outcome.

RESULTS

Three hundred and ninety patients were included. The ICU mortality rate was 56% (N.=220) and 64% of patients (N.=251) had an unfavorable 3-month neurological outcome. The median RDW on the day of admission was 14% (13.0-15.2%) and remained stable over the observation period. Two hundred and forty-five patients (63%) had a high RDW (>13.4%) on admission. In multivariable logistic regression analysis, older age, absence of bystander cardiopulmonary resuscitation (CPR), a non-cardiac etiology of the arrest, a non-shockable initial rhythm, high adrenaline dose during CPR and high admission RDW levels were independently associated with an unfavorable outcome at 3 months.

CONCLUSIONS

High RDW values are associated with poor neurological outcome among CA survivors.

The impact of extracerebral organ failure on outcome of patients after cardiac arrest: an observational study from the ICON database

Background

We used data from a large international database to assess the incidence and impact of extracerebral organ dysfunction on prognosis of patients admitted after cardiac arrest (CA).

Methods

This was a sub-analysis of the Intensive Care Over Nations (ICON) database, which contains data from all adult patients admitted to one of 730 participating intensive care units (ICUs) in 84 countries from 8–18 May 2012, except admissions for routine postoperative surveillance. For this analysis, patients admitted after CA (defined as those with “post-anoxic coma” or “cardiac arrest” as the reason for ICU admission) were included. Data were collected daily in the ICU for a maximum of 28 days; patients were followed up for outcome data until death, hospital discharge, or a maximum of 60 days in-hospital. Favorable neurological outcome was defined as alive at hospital discharge with a last available neurological Sequential Organ Failure Assessment (SOFA) subscore of 0–2.

Results

Among the 469 patients admitted after CA, 250 (53 %) had had out-of-hospital CA; 210 (45 %) patients died in the ICU and 357 (76 %) had an unfavorable neurological outcome. Non-survivors had a higher incidence of renal (43 vs. 16 %), cardiovascular (56 vs. 45 %), and respiratory (62 vs. 48 %) failure on admission and during the ICU stay than survivors (all p < 0.05). Similar results were found for patients with unfavorable vs. favorable neurological outcomes. In multivariable analysis, independent predictors of ICU mortality were renal failure on admission, high admission Simplified Acute Physiology Score (SAPS) II, high maximum serum lactate levels within the first 24 h after ICU admission, and development of sepsis. Independent predictors of unfavorable neurological outcome were mechanical ventilation on admission, high admission SAPS II score, and neurological dysfunction on admission.

Conclusions

In this multicenter cohort, extracerebral organ dysfunction was common in CA patients. Renal failure on admission was the only extracerebral organ dysfunction independently associated with higher ICU mortality.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-016-1528-6) contains supplementary material, which is available to authorized users.

Colloids for fluid resuscitation: what is their role in patients with shock?

BACKGROUND

Fluid therapy is widely used in critically ill patients to restore effective intravascular volume and improve organ perfusion. Recent studies have questioned the administration of colloid-based solutions, especially if containing hydroxyethyl starch (HES), in different ICU populations; however, there is still uncertainty on the use of colloids as initial fluid therapy for early resuscitation.

METHODS

The aim of this study was to investigate the effect of two different resuscitation fluid strategies on the mortality of patients with shock. In a multicentric (57 ICUs), controlled, open-label trial (from February 2003 to August 2012), the authors randomized patients with signs of acute hypovolemia, defined by the combination of hypotension, evidence of low filling pressures or cardiac index and at least two signs of tissue hypoperfusion (such as altered consciousness, mottled skin, oliguria, lactate levels > 2 mmol/L), to received either a colloid- or crystalloid-based therapy. Both cohorts received maintenance fluids consisting in isotonic crystalloids and albumin in case of severe hypoalbuminemia (<2 g/dL). Exclusion criteria included previous fluid therapy, pregnancy, brain death, extended burns, chronic hemodialysis or liver disease, known coagulopathy, acute anaphylaxis, dehydration and hypotension due to sedative drugs.

RESULTS

Among the 6498 eligible patients, 2857 were eventually randomized in one of the two groups. The 28-day mortality was 25.4% in the colloid and 27.0% in the crystalloid group (P=0.26). In the sub-group analysis, similar mortality rates were reported for shock due to hypovolemia, sepsis or trauma. Also, the use of continuous renal replacement therapy was similar between groups (11.0% vs. 12.5%, P=0.19). There were more days alive without mechanical ventilation or vasopressors during the first 7 and 28 days and a lower 90-day mortality in the colloid group.

CONCLUSION

These data suggest that mortality was not increased and probably decreased with the use of colloids in different forms of shock requiring early fluid resuscitation. We discussed herein some methodological issues that may explain the discrepancies of this trial with the other studies developed in the same field.

How to target temperature after cardiac arrest: insights from a randomized clinical trial

Implementation of treatments able to improve survival and neurological recovery of cardiac arrest (CA) survivors is a major clinical challenge. More than ten years ago, two pivotal trials showed that application of therapeutic hypothermia (TH, 32-34 °C) to patients resuscitated from an out-of-hospital CA (OHCA) with an initial shockable rhythm significantly ameliorated their outcome. Since then, TH has been used also for non-shockable rhythms and for in-hospital CA to some extent, even if the quality of evidence supporting TH in such situations remained very low. The objective of this randomized, controlled, multicenter study (named "Targeted Temperature Management" TTM study) was to compare two different strategies of temperature control after CA; patients were randomized to be treated either at 33 °C or at 36 °C for 24 hours, while fever was accurately avoided for the first 3 days since randomization. Inclusion criteria were: Glasgow Coma Score <8, presumed cardiac origin of arrest, randomization occurring within the first 4 hours from the return of spontaneous circulation. Patients were excluded if they had an unwitnessed arrest with asystole as the initial rhythm, suspected or known acute intracranial hemorrhage or stroke, and a body temperature of less than 30 °C. A specific algorithm was used to decide for withdrawal of care in patients remaining comatose after 72 hours since normothermia was achieved. The primary outcome was 6-month mortality. After the enrollment of 939 patients, the authors did not find any significant difference between groups in primary outcome (235/473 [50%] and 225/466 [48%] of patients died in 33 °C and 36 °C group, respectively; HR for death if in the 33 °C group, 1.06 [95% CI 0.89 to 1.28; P=0.51]). Similarly, the analysis of the composite outcome of death or poor neurologic function yielded similar results between the two groups. This is the largest study evaluating the effects of two different strategies of temperature management after CA. Some important concerns have been raised on the real benefit of keeping CA patients at 33 °C and major changes in clinical practice are expected. We discussed herein the main differences with previous randomized trials and tried to identify possible explanations for these findings.

Non-invasive ventilation during upper endoscopies in adult patients. A systematic review

BACKGROUND

Upper endoscopies (UE) are widely performed. Non-invasive ventilation (NIV) during UE has been used to avoid respiratory complications, mainly in high-risk or sedated patients. We performed a systematic review on this topic.

METHODS

BioMedCentral, PubMed, Embase and the Cochrane Central Register of Clinical Trials were searched (updated September 1, 2012). Further searches involved conference proceedings.

RESULTS

We included in this systematic review 27 papers out of 405 publications retrieved. Ten studies reported the use without complications of NIV to assist fiberoptic bronchoscopy (FOB) and broncho-alveolar lavage (BAL). Ten studies described the use of NIV in fiberoptic-guided tracheal intubations. The authors reported no complications, even in hypoxemic patients and they observed only one failure (0.4%). Three studies evaluated the effectiveness of NIV during placement of percutaneous endoscopic gastrostomy in patients with neuromuscular diseases. In this group the failure rate was 4.4%. One study described the successful use of NIV in sedated patients undergoing gastroscopy. Three studies reported the successful application of NIV during trans-esophageal echocardiography. Overall, the procedure could not be performed due to inability of NIV to maintain safe intra-procedural ventilation in four out of total 515 cases of NIV-aided UE, suggesting a success rate higher than 99.2%.

CONCLUSION

This is the first systematic review addressing the use of NIV during upper endoscopies. Its use seems feasible, and based on the limited data available NIV appears safe and likely effective. The patients who would benefit the most are: high-risk and patients undergoing sedation.

Non-invasive ventilation in cardiac surgery: a concise review

Mild to severe respiratory dysfunction is still a common issue after cardiac surgery. Postoperative respiratory complications are associated with prolonged hospitalization and worse survival. In this high-risk surgery, non-invasive ventilation could have relevant positive effects. The present narrative concise review aims to summarize available data on the role of non-invasive ventilation before and after cardiac surgery. Non-invasive ventilation exerts its main effects on the pulmonary and on the cardiovascular systems.  Non-invasive ventilation can be applied to prevent acute respiratory failure; it can also be prescribed as a curative tool to treat an established postoperative acute respiratory failure. Non-invasive ventilation could also be applied to wean patients from mechanical ventilation. When applied as a preventive tool, the main scope is the prevention of pneumonia by resolving or preventing atelectasis. So far, limited (but encouraging) data are available: its routine use in all patients to prevent postoperative acute respiratory failure cannot be recommended. Non-invasive ventilation to treat postoperative acute respiratory failure has been evaluated more extensively. A failure rate from 10 to 55% was reported. Safety appears preserved, with no relevant hemodynamic complication reported. Non-invasive ventilation has also been applied during percutaneous aortic valve implant in patients unable to lie supine due to severe respiratory limitation and orthopnea. In conclusion, non-invasive ventilation has the potential to be very useful before and after cardiac surgery. So far, results are promising but available data are limited. Training and experience are essential to obtain positive results and to avoid complications.

Non-invasive ventilation after cardiac surgery outside the Intensive Care Unit

BACKGROUND

Non-invasive ventilation (NIV) can prevent or treat postoperative acute respiratory failure. NIV after discharge from the Intensive Care Unit (ICU) has never been described in the setting of cardiac surgery.

METHODS

This study enrolled 85 patients who received NIV in the main ward as treatment for respiratory failure. The patients had the following conditions: atelectasis (45 patients), pleural effusion (20 patients), pulmonary congestion (13 patients), diaphragm hemiparesis (6 patients), pneumonia (4 patients) or a combination of these conditions.

RESULTS

Eighty-three patients were discharged from the hospital in good condition and without need for further NIV treatment, while two died in-hospital. Four of the 85 patients had an immediate NIV failure, while eight patients had delayed NIV failure. Only one patient had a NIV-related complication represented by hypotension after NIV institution. In this patient, NIV was interrupted with no consequences. Major mistakes were mask malpositioning with excessive air leaks (7 patients), incorrect preparation of the circuit (one patient), and oxygen tube disconnection (one patient). Minor mistakes (sub-optimal positioning of the face mask without excessive air leaks) were noted by the respiratory therapists for all patients and were managed by slightly modifying the mask position.

CONCLUSION

In our experience, postoperative NIV is feasible, safe and effective in treating postoperative acute respiratory failure when applied in the cardiac surgical ward, preserving intensive care unit beds for surgical activity. A respiratory therapy service managed the treatment in conjunction with ward nurses, while an anesthesiologist and a cardiologist served as consultants.

Epidural analgesia improves outcome in cardiac surgery: a meta-analysis of randomized controlled trials

OBJECTIVE

The authors conducted a review of randomized studies to determine whether there were any advantages for clinically relevant outcomes by adding epidural analgesia in patients undergoing cardiac surgery under general anesthesia.

DESIGN

Meta-analysis.

SETTING

Hospitals.

PARTICIPANTS

A total of 2366 patients from 33 randomized trials.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

DATA SOURCES AND STUDY SELECTION

PubMed, BioMedCentral, CENTRAL, EMBASE, Cochrane Central Register of Controlled Trials, and conference proceedings were searched (updated January 2008) for randomized trials that compared general anesthesia with an anesthetic plan including general anesthesia and epidural analgesia in cardiac surgery. Two independent reviewers appraised study quality, with divergences resolved by consensus. Overall analysis showed that epidural analgesia reduced the risk of the composite endpoint mortality and myocardial infarction (30/1125 [2.7%] in the epidural group v 64/1241 [5.2%] in the control arm, odds ratio [OR] = 0.61 [0.40-0.95], p = 0.03 number needed to treat [NNT] = 40), the risk of acute renal failure (35/590 [5.9%] in the epidural group v 54/618 [8.7%] in the control arm, OR = 0.56 [0.34-0.93], p = 0.02, NNT = 36), and the time of mechanical ventilation (weighted mean differences = -2.48 hours [-2.64, -2.32], p < 0.001).

CONCLUSIONS

This analysis suggested that epidural analgesia on top of general anesthesia reduced the incidence of perioperative acute renal failure, the time on mechanical ventilation, and the composite endpoint of mortality and myocardial infarction in patients undergoing cardiac surgery.

A unique carboxy-terminus truncation mutant of the retinoic acid receptor alpha gene associated with a variant marker chromosome in a retinoic acid resistant HL-60 subline

In order to contribute to the study of the molecular basis of leukemic cellular resistance to the induction of differentiation by all-trans retinoic acid (RA) we have generated and analyzed a mutant, RA-resistant HL-60 cell line. Molecular analysis of the retinoic acid receptor alpha (RARalpha) cDNA disclosed, in one of the two alleles, a novel mutation consisting of a 7-base deletion in the ligand binding domain that includes part of a FokI restriction endonuclease site previously described. As a consequence of this deletion and translational frame-shift, a stop signal is created that truncates the protein at codon 421, disrupting an essential functional component of the receptor. Transducing an epitope tagged RARalpha into the mutant is sufficient to inhibit clonal growth in the presence of RA. Standard cytogenetic analysis, fluorescent in situ hybridization (FISH) and comparative genomic hybridization (CGH) analysis revealed the presence of two RARalpha loci, and showed a composite karyotype with additional abnormalities with respect to the parental line, including a chromosome 8 insertion in a chromosome previously known as marker three.

Extractive spectroscopic insulin determination in pharmaceutical formulations

Two methods are proposed, one spectrophotometric and one spectrofluorimetric, for the determination of insulin in several pharmaceutical formulations. The methods were found to be fairly simple, sensitive and accurate, and thus suitable for this purpose. Both methods involve an extractive step with diethyl ether for the elimination of excipient interference, and subsequent direct spectrometric analysis. Spectrophotometric determinations were carried out at lambda = 276 nm; spectrofluorimetric determinations were carried out at lambda em = 306 nm with lambda exc = 277 nm.

Experimental analysis of tensile properties of some suturing materials

The aim of the investigation is to quantitatively evaluate the failure load of several suture materials currently used in dentistry surgery. No chromic catgut, silk, Prolene, Ethilon, Ethibond, Vicryl and Vicryl Rapid, obtained from Ethicon s.p.a., in the sizes 3-0, 4-0, and 5-0 have been tested. The analysis has been carried out measuring the diameter of each suture with an optical microscope to determine the accuracy of manufacturers' data. Tensile testing has been performed to evaluate the failure load of each material. Finally, sutures of the same effective diameter class have been compared relative to failure load. Results show that monofilament sutures present a failure load remarkably superior to that of multifilament sutures. Using SEM analysis monofilament sutures present less surface irregularities than multifilament sutures. Only monofilaments Ethilon 4-0 and 5-0, Prolene 4-0, and multifilament no chromic catgut 4-0 and 5-0 meet the requirements of the Italian Pharmacopeia. In contrast, Prolene 5-0 and the other multifilaments, silk, Ethibond, Vicryl and Vicryl rapid, have a larger diameter than that declared on the label by the producer.

[The choleretic effects of licorice: identification and determination of the pharmacologically active components of Glycyrrhiza glabra]

Recent studies indicate that licorice extract, when administered per os or i.v., causes an evident choleretic effect in rats. Aim of this research is to identify and quantify those licorice constituents which are responsable for the observed choleresis. The quali-quantitative analysis of umbelliferon (7-idroxycoumarin), was at first performed by a fluorimetric method, subsequently by a more selective HPLC method. Moreover, this HPLC method allows the determination of glycyrrhizin, an important licorice constituent. Unlike the glycyrrhizin, which is present in a fairly large amount, umbelliferon resulted to be present at a very low concentration (at trace level), both in licorice and in bile. Research is in progress, aiming to determine the substances, beyond glycyrrhizin, which are responsable for the choleretic effect of licorice.

Homeostasis and narcolepsy

Narcolepsy is characterized by irresistible daytime sleep episodes and cataplectic attacks. Because of the finding of an ultradian rhythmicity of slow-wave sleep in narcolepsy, an alteration of nonrapid eye movement sleep homeostatic regulation has been hypothesized to explain the impairment of the sleep-wakefulness cycle. This hypothesis was tested by two different methods: 1) a sleep-deprivation method (16 or 24 hours) increasing the prior sleep wakefulness and 2) a bed-rest method shortening the prior sleep wakefulness. In both studies normal subjects, sex- and age-matched to narcoleptic subjects, served as controls. Although some differences could be evidenced between the two groups, it was clearly shown that the homeostatic process was functional in narcolepsy and that narcoleptics seemed to be more sensitive to homeostatic regulation of sleep than normal subjects.

HPLC determination of glycyrrhizin and glycyrrhetic acid in biological fluids, after licorice extract administration to humans and rats

Simple and sensitive HPLC methods were developed for the determination of glycyrrhyzin (G) and its main metabolite glycyrrhetic acid (GA) in biological samples, in order to investigate the pharmacokinetic behaviour of G after oral administration of licorice extract (LE) or G to humans and rats. The analysis have been carried out by HPLC with UV detector (251 nm), after a careful pretreatment of the samples. These methods are suitable in terms of precision and accuracy for the G and GA determination in plasma and urine of human volunteers and in bile, plasma ad urine of rats.

Spectrophotometric determination of glutathione and of its oxidation product in pharmaceutical dosage forms

A simple and sensitive spectrophotometric method suitable for the stability control of pharmaceutical dosage forms containing glutathione (gamma-glutamyl-cysteinyl-glycine), GSH, is described. Besides GSH, the method quantitatively determines its oxidation product, GSSG. The colour reactions of GSH and GSSG with ammonium tetrachloropalladate have been investigated and the optimum reaction conditions, spectral characteristics and composition of the yellow water-soluble complexes have been established. The assay results of pharmaceutical formulations showed good accuracy and precision over the concentration range of 5 x 10(-5)-6 x 10(-4) M GSH.

A study of possible interferences in colorimetric determination of potassium in pharmaceutical formulations

A study of interferences in the colorimetric determination of potassium, extracted as ion-pair [K-18-crown-6]+ picrate- in the toluene-methylene chloride (80:20) solvent mixture, was carried out. The species examined were those likely to be found, together with the K ion, in typical pharmaceutical formulations, namely, organic bases and inorganic cations.

[Gas chromatographic determination of aluminum in pharmaceutical formulations]

A gas chromatographic method for the determination of Al3+ in pharmaceutical formulations, based on the complex formation between the cation and the trifluoroacetylacetone reagent is reported. The results obtained indicate that the proposed method is suitable, on account of accuracy and precision, for a reliable quality control of commercial dosage forms.

Determination of potassium in pharmaceutical formulations by means of 18-crown-6: extraction studies

A colorimetric method has been developed for the determination of potassium in pharmaceutical formulations. The method is based on the formation of a complex of potassium with 18-crown-6, followed by conversion to an ion-pair with picrate anion; the ion-pair is extracted with either methylene chloride or toluene-methylene chloride (80:20, v/v) and determined colorimetrically.