Pulmonary complications following liver transplantation in pediatric patients

Estimating risk of prolonged mechanical ventilation after liver transplantation in children: PROVE-ALT score

BACKGROUND

Children at high risk for prolonged mechanical ventilation (PMV) after liver transplantation (LT) need to be identified early to optimize pulmonary support, allocate resources, and improve surgical outcomes. We aimed to develop and validate a metric that can estimate risk for Prolonged Ventilation After LT (PROVE-ALT).

METHODS

We identified preoperative risk factors for PMV by univariable analysis in a retrospective cohort of pediatric LT recipients between 2011 and 2017 (n = 205; derivation cohort). We created the PROVE-ALT score by mapping multivariable logistic regression coefficients as integers, with cutoff values using the Youden Index. We validated the score by C-statistic in a retrospectively collected separate cohort of pediatric LT recipients between 2018 and 2021 (n = 133, validation cohort).

RESULTS

Among total 338 patients, 21% (n = 72) were infants; 49% (n = 167) had cirrhosis; 8% (n = 27) required continuous renal replacement therapy (CRRT); and 32% (n = 111) required management in hospital (MIH) before LT. Incidence of PMV post-LT was 20% (n = 69) and 3% (n = 12) required tracheostomy. Independent risk factors (OR [95% CI]) for PMV were cirrhosis (3.8 [1-14], p = .04); age <1-year (8.2 [2-30], p = .001); need for preoperative CRRT (6.3 [1.2-32], p = .02); and MIH before LT (12.4 [2.1-71], p = .004). PROVE-ALT score ≥8 [Range = 0-21] accurately predicted PMV in the validation cohort with 73% sensitivity and 80% specificity (AUC: 0.81; 95% CI: 0.71-0.91).

CONCLUSION

PROVE-ALT can predict PMV after pediatric LT with a high degree of sensitivity and specificity. Once externally validated in other centers, PROVE-ALT will empower clinicians to plan patient-specific ventilation strategies, provide parental anticipatory guidance, and optimize hospital resources.

Metastatic pulmonary calcifications after pediatric liver transplantation

BACKGROUND

Pulmonary calcification (PC) is a rare clinical entity observed following liver transplantation (LT). Most often identified in adults or in patients with concomitant renal failure, PC is rarely reported in children. While the clinical course of PC is largely benign, cases of progressive respiratory failure and death have been reported. Additionally, PC may mimic several other disease processes making diagnosis and management challenging. Currently, little is reported regarding the diagnosis, management, and long-term outcomes of children with PC following LT.

METHODS

We performed a retrospective chart review of patients undergoing LT at our institution between 2006 and 2023. We identified two patients who developed PC following LT. Their diagnosis, clinical course, and long-term outcomes are reported. A literature review of the presentation, diagnosis, management, and outcomes of adult and pediatric patients with PC post-LT was also performed.

CONCLUSIONS

Pulmonary calcifications are a rare but notable complication after pediatric liver transplantation. Our case series adds to the limited literature on this clinical entity in children but also highlights the fact that effective diagnosis and treatment may be safely accomplished without the use of lung biopsy.

Neutrophil extracellular traps predict postoperative pulmonary complications in paediatric patients undergoing parental liver transplantation

BACKGROUND

Parental liver transplantation (PLT) improves long-term survival rates in paediatric hepatic failure patients; however, the mechanism of PLT-induced postoperative pulmonary complications (PPCs) is unclear.

METHODS

A total of 133 paediatric patients undergoing PLT were included. Serum levels of NET components, including circulating free DNA (cfDNA), DNA-histone complex, and myeloperoxidase (MPO)-DNA complex, were detected. The occurrence of PPCs post-PLT, prolonged intensive care unit (ICU) stay and death within one year were recorded as the primary and secondary outcomes.

RESULTS

The overall rate of PPCs in the hospital was 47.4%. High levels of serum cfDNA, DNA-histone complexes and MPO-DNA complexes were associated with an increased risk of PPCs (for cfDNA, OR 2.24; for DNA-histone complex, OR 1.64; and for MPO-DNA, OR 1.94), prolonged ICU stay (OR 1.98, 4.26 and 3.69, respectively), and death within one year (OR 1.53, 2.65 and 1.85, respectively). The area under the curve of NET components for the prediction of PPCs was 0.843 for cfDNA, 0.813 for DNA-histone complexes, and 0.906 for MPO-DNA complexes. During the one-year follow-up, the death rate was higher in patients with PPCs than in patients without PPCs (14.3% vs. 2.9%, P = 0.001).

CONCLUSIONS

High serum levels of NET components are associated with an increased incidence of PPCs and death within one year in paediatric patients undergoing PLT. Serum levels of NET components serve as a biomarker for post-PLT PPCs and a prognostic indicator.

Rescue venovenous extracorporeal membrane oxygenation for the deterioration of acute respiratory distress syndrome in pediatric liver transplantation

BACKGROUND

Twenty percent of pediatric patients with BA develop ACLF with increased mortality while awaiting LT. Respiratory complications are common in pediatric ACLF and are associated with increased morbidity and mortality. ARDS is the most severe manifestation of acute respiratory failure with considerable risk of mortality.

METHODS

A 5-month-old girl with post-Kasai BA preoperatively experienced ARDS from RSV infection while awaiting LT. She developed decompensated liver failure with shock, acute kidney injury, coagulopathy, and pulmonary hemorrhage after several episodes of sepsis over the course of 1 month in the PICU. At this stage, RSV was not detected in the patient's tracheal aspirate by real-time polymerase chain reaction. She underwent living donor LT to manage her pre-existing critical state. Following reperfusion during LT, her pre-existing ARDS rapidly deteriorated, which was alleviated by intraoperative VV ECMO.

RESULTS

Severe respiratory acidosis improved rapidly following ECMO, and LT was completed uneventfully. The patient was successfully weaned off ECMO on POD 3.

CONCLUSIONS

This is the first pediatric case rescued by the intraoperative application of ECMO during LT. Our case and cumulative evidence suggest that VV ECMO can serve as rescue therapy for perioperative refractory respiratory failure in pediatric LT.

Factors associated with postoperative respiratory conditions and critical outcomes on pediatric liver transplantation: A single-center experience

BACKGROUND

Orthotopic liver transplantation (OLT) is an established therapeutic option for pediatric end-stage liver disease (PELD). The postoperative respiratory conditions of OLT recipients may be associated with subsequent clinical outcomes including length of stay (LOS) in the pediatric intensive care unit (PICU). This study aimed to characterize the postoperative respiratory conditions, associated factors, and outcomes after pediatric OLT.

METHODS

Clinical data of children receiving OLT from July 2014 to July 2020 were retrospectively collected. Postoperative respiratory conditions were defined as time to extubation, significant pleural effusion, and initial postoperative PaO2/FiO2 ratio. Logistic and multiple regressions were applied to analyze the associations among clinical factors, postoperative respiratory conditions, and clinical outcomes.

RESULTS

Twenty-two patients with median age of 1.4-year-old (range: 25 days to 12 years old) were analyzed. Mortality within 28 days was 4.5% and median LOS in the PICU was 18 days. Of 22 patients, 11 patients (50.0%) were extubated over 24 hours after surgery, and 8 patients (36.4%) required drainage for pleural effusions. Longer LOS in the PICU were noted in patients extubated over 24 hours (p = 0.008), complicated with significant pleural effusions (p = 0.02) after surgery, and having low initial postoperative PaO2/FiO2 (<300 mmHg) (p = 0.001). Among clinical factors, massive intraoperative blood transfusion (>40 mL/kg) was significantly associated with prolonged intubations, significant pleural effusions, low initial postoperative PaO2/FiO2, and prolonged LOS in the PICU (>14 days). The initial postoperative PaO2/FiO2 significantly depended on age, disease severity (PELD score), and whether the patient received massive intraoperative blood transfusion.

CONCLUSION

Pediatric patients of OLT with poor postoperative respiratory conditions including low initial PaO2/FiO2 ratio, extubation over 24 hours or significant pleural effusions have longer LOS in the PICU, and the requirement of massive intraoperative transfusion was a risk factor for both poor postoperative respiratory conditions and prolonged LOS in the PICU.

The use of tracheostomy to support critically ill children receiving orthotopic liver transplantation: a single-center experience

BACKGROUND

Children with end-stage liver disease and multi-organ failure, previously considered as poor surgical candidates, can now benefit from liver transplantation (LT). They often need prolonged mechanical ventilation (MV) post-LT and may need tracheostomy to advance care. Data on tracheostomy after pediatric LT are lacking.

METHOD

Retrospective chart review of children who required tracheostomy in the peri-LT period in a large, freestanding quaternary children's hospital from 2014 to 2019.

RESULTS

Out of 205 total orthotopic LTs performed in 200 children, 18 (9%) required tracheostomy in the peri-transplant period: 4 (2%) pre-LT and 14 (7%) post-LT. Among those 14 needing tracheostomy post-LT, median age was 9 months [IQR = 7, 14] at LT and 10 months [9, 17] at tracheostomy. Nine (64%) were infants and 12 (85%) were cirrhotic at the time of LT. Seven (50%) were intubated before LT. Median MV days prior to LT was 23 [7, 36]. Eight (57%) patients received perioperative continuous renal replacement therapy (CRRT). The median MV days from LT to tracheostomy was 46 [33, 56]; total MV days from initial intubation to tracheostomy was 57 [37, 66]. Four (28%) children died, of which 3 (21%) died within 1 year of transplant. Total ICU and hospital length of stay were 92 days [I72, 126] and 177 days [115, 212] respectively. Among survivors, 3/10 (30%) required MV at home and 8/10 (80%) were successfully decannulated at 400 median days [283, 584].

CONCLUSION

Tracheostomy though rare after LT remains a feasible option to support and rehabilitate critically ill children who need prolonged MV in the peri-LT period.

Extracorporeal Membrane Oxygenation in Pediatric Liver Transplantation: A Multicenter Linked Database Analysis and Systematic Review of the Literature

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) can be used to maintain oxygen delivery and provide hemodynamic support in case of circulatory and respiratory failure. Although the role of ECMO has emerged in the setting of adult liver transplantation (LT), data in children are limited. We aimed to describe the characteristics and outcomes of children receiving ECMO support at the time of or following LT.

METHODS

All pediatric LT recipients (≤20 y) requiring ECMO support peri-/post-LT were identified from a linked Pediatric Health Information System/Scientific Registry of Transplant Recipients dataset (2002-2018). The Kaplan-Meier method and Cox regression analysis were used to assess post-ECMO survival. A systematic literature review was conducted in accordance with the PRISMA statement.

RESULTS

Thirty-four children required ECMO peri-/post-LT. The median time from LT to ECMO was 5 d (interquartile range, 0.0-12.3), and the median ECMO duration was 1 d (interquartile range, 1.0-6.3). Children started on ECMO within 1 d of LT exhibited superior survival compared with those started on ECMO later (P = 0.03). When adjusting for recipient weight, increasing time from LT to ECMO initiation was associated with increased risk of mortality (hazard ratio, 1.03; 95% confidence interval, 1.00-1.06; P = 0.049). Overall, 55.9% (n = 19 of 34) of the patients survived. Twenty-two children receiving ECMO in the peri-/post-LT period were systematically reviewed, and 15 of them survived (68.2%).

CONCLUSIONS

With an encouraging >55% patient survival at 6 mo, ECMO should be considered as a viable option in pediatric LT recipients with potentially reversible severe respiratory or cardiovascular failure refractory to conventional treatment.

Diaphragmatic Hernia after Pediatric Living Donor Liver Transplantation: An Indian Experience with Review of Literature

Aim:

Although intestinal obstruction following living donor liver transplantation (LDLT) is relatively common, diaphragmatic hernia (DH) as the attributing cause is rarely reported. The study aimed to find out the incidence, clinical presentation, and management of DH after liver transplant in pediatric patients.

Materials and Methods:

A retrospective review of all cases of pediatric liver transplants was performed. Case sheets, operation records, and investigations including radiology were studied.

Results:

Out of 79 cases of pediatric liver transplants, two cases of posttransplant DH were identified. The first case is a 2-year-old male child who was transplanted for progressive familial intrahepatic cholestasis, and the second one is a 4-year-old boy who underwent LDLT for hepatitis A-induced acute liver failure. The first child presented abdominal symptoms and the second one with pulmonary symptoms. The DHs were diagnosed at 132 and 70 days, respectively, posttransplant by chest radiographs and computed tomography scan. The defects were located at the posteromedial aspect of the diaphragm in both the cases and were closed by primary closure with mesh reinforcement. Both the children are doing well with no recurrence.

Conclusion:

High index of clinical suspicion is mandated in pediatric patients after liver transplant and once the diagnosis is confirmed, urgent surgical exploration is mandatory.

Baseline neutrophil-lymphocyte ratio is associated with survival for infant living donor liver transplantation for biliary atresia

Living donor liver transplantation (LDLT) in infants for congenital biliary atresia (BA) poses various challenges nowadays. We aim to investigate independent preoperative risk factors for LDLT in infants. We retrospectively analyzed medical records of infant patients who underwent LDLT surgery for BA from 1 July 2014 to 31 December 2016. Cox regression was used to explore risk factors. The Kaplan-Meier method was used to calculate the recipient and graft survival, and subgroup analysis was then applied according to the risk factors. Independent t test or Mann-Whitney U test was applied for comparison of certain factors between survival patients and death. A total of 345 infant LDLT for BA were included in the analysis. In the multivariate Cox-regression model, 3 factors were determined as independent risk factors for recipient and graft survival, there were neutrophil-lymphocyte ratio (NLR), pediatric end-stage liver disease (PELD), and recipient age. The HR (95% CI) of baseline NLR for recipient and graft survival were 1.25 (1.12-1.38) and 1.25 (1.13-1.39), with all P < .0001. Kaplan-Meier curves for NLR using different cut-offs (1.5; 1, 2) suggested that higher baseline NLR was significantly associated with recipient and graft survival. The subgroup analysis indicated that for infants with elevated NLR, the recipient survival was significantly lower when their age >6 months or PELD >20. Our results indicate that infants with higher baseline NLR value may have lower survival rate 3 years after transplantation. Further investigations about broaden the application of pre- and post-transplant NLR to guide nutrition intervention and immunosuppression therapy are necessary.

Pulmonary complications after liver transplantation in children: risk factors and impact on early post-operative morbidity

Liver transplantation (LT) is associated with high post-operative morbidity, despite excellent survival rates. With this retrospective study, we report the incidence of early and late pulmonary complications (PC) after LT, identify modifiable risk factors for PC and analyzed the role of PC in post-operative ventilation duration and hospital length of stay. In a series of 79 children (0-16 years) with LT over a 12 years period, early (<3 months post-LT) and/or late (>3 months post-LT) PC occurred in 68 patients (86%). Sixty-four percent (64%) developed early major complications such as pulmonary edema, atelectasis, or pleural effusion. Atelectasis requiring an intervention (P ≤ .02), pulmonary edema (P ≤ .02), or elevated PELD/MELD scores (P = .05) were associated with an increase in total ventilation duration and length of stay in the ICU. Risk factors for early PC included preoperative hypoxemia (P = .005), low serum albumin at LT admission (P = .003), or early rejection (P = .002). About 20% of patients experienced late PC of which 81% were infections. Risk factor assessment prior to LT may ultimately help reduce early PC thereby possibly minimizing post-operative morbidity and ICU length of stay.

Successful venoarterial extracorporeal membrane oxygenation for postoperative septic shock in a child with liver transplantation: A case report

Refractory septic shock after LT is a life-threatening complication. VA ECMO is used to treat refractory cardiorespiratory failure. We present herein the case of a 5-year-old girl with post-Kasai biliary atresia, who underwent a living donor LT and suffered refractory septic shock. VA ECMO was indicated due to progressive cardiac deterioration. After full recovery of her EF, she has been steadily improving and has shown good liver function and no neurological sequelae. This is the first report of successful VA ECMO in a post- LT patient with refractory septic shock.

Successful venoarterial extracorporeal membrane oxygenation for prolonged hepatopulmonary syndrome following pediatric liver transplantation: A case report and review of the literature

HPS is a major complicating feature of end-stage liver disease. Diagnosis is clinical, and LT is the only definitive treatment. While the general impression is that HPS improves quickly after transplantation, it may not always be the case. We describe the smallest reported child with HPS prior to LT and requiring prolonged venoarterial extracorporeal membrane oxygenation after LT; especially as it is a rare occurrence, physician managing such cases should be aware of the circumstances under which HPS may require specific treatment.

Bilateral diaphragmatic paresis following pediatric liver transplantation

Background:

Although diaphragm paresis or paralysis is fairly common following cardiac procedures; it is a less common complication following liver transplantation. Unilateral diaphragm paresis, usually right sided, has been described following liver transplantation in adults and has been rarely described in children.

Purpose:

Diaphragmatic injury following LT is often unrecognized and is typically unilateral, involving the right hemidiaphragm. Bilateral diaphragm dysfunction following liver transplantation in children is a rare complication.

Methods:

This is a case report of bilateral diaphragm paresis in a young child following a repeat liver transplantation.

Conclusion:

Bilateral diaphragm paresis following liver transplantation in children is rare and spontaneous resolution is possible. A conservative approach with noninvasive ventilation as a first line treatment to allow the diaphragm to regain function should be considered.

Real-time ultrasound-guided placement of a pigtail catheter in supine position for draining pleural effusion in pediatric patients who have undergone liver transplantation

PURPOSE

Ultrasound (US) guidance is currently used for placement of wire-guided thoracic drains, and its use is associated with a decreased risk of complications. However, most studies conducted to date in this field have been performed on adult patients. The aim of this study was to report the technical success and complication rates observed during real-time US-guided placement of a thoracic pigtail catheter in pediatric liver-transplant recipients with symptomatic pleural effusion.

METHODS

This was a single-center retrospective review of the clinical records and images from pediatric liver-transplant patients with symptomatic pleural effusion who had undergone real-time US-guided pleural-space puncture followed by placement (via the Seldinger technique) of a pigtail catheter for drainage, between May 2006 and June 2014.

RESULTS

We identified 25 patients who had undergone 41 pigtail catheter-placement procedures during the study period. The patients' mean age (± SD) was 4.2 ± 3.9 years (range, 2 months to 16 years), and their mean weight was 14.2 ± 7.2 kg (range, 4.5-33 kg). Seventeen procedures had been performed in the intensive care unit, and 8, in patients undergoing mechanical ventilation. Twelve of the 41 procedures had been performed in patients with altered hemostasis (ie, platelet count < 50 × 10(3) /μl and/or international normalized ratio > 1.5). The size of the pigtail catheters ranged from 5 F to 8.5 F. The technical success rate was 100%, with no major complications such as pneumothorax or hemothorax. Accidental dislocation of the catheter occurred in four patients (9%) over 3-10 days after the first procedure.

CONCLUSIONS

In our experience, real-time US-guided pleural-space puncture, performed at bedside, with the patient in the supine position, followed by placement of a pigtail catheter for drainage of effusion, is safe to use and has a high rate of technical success in pediatric patients. © 2015 Wiley Periodicals, Inc. J Clin Ultrasound 44:284-289, 2016.

Awareness of Respiratory Failure Can Predict Early Postoperative Pulmonary Complications in Liver Transplant Recipients

OBJECTIVES

Cardiovascular and respiratory system complications are the most common causes of early mortality after liver transplant. We evaluated the causes of respiratory failure as an early postoperative pulmonary complication in liver transplant recipients.

MATERIALS AND METHODS

Patients who underwent orthotropic liver transplant between 2001 and 2014 were retrospectively evaluated. Clinical and demographic variables and pulmonary complications at the first and second visit after transplant were noted. The first visit was within the first week and the second was between 1 and 4 weeks after transplant. An arterial oxygen saturation value below 90% in room air for at least 1 day was considered a medically significant respiratory failure.

RESULTS

Our study included 204 (148 men and 56 women; mean age 43.0.4 ± 13.06 y) adult liver transplant recipients (46 from deceased and 158 from living donors). At the first visit after transplant, 161 patients (79%) had postoperative pulmonary complications, including pleural effusion accompanied by atelectasis (47.1%), only atelectasis (17.2%), and only pleural effusion (10.3%). At the second visit, complications included atelectasis associated with pleural effusion (12.3%) and pneumonia (12.3%). All patients had documented respiratory failure at the first visit, and 92 patients (45.1%) had respiratory failure at the second visit. Causes of respiratory failure at the first visit included atelectasis in 35 patients (17.2%) and atelectasis accompanied by pleural effusion in 96 patients (47.1%). At the second visit, 25 of 161 patients (25.3%) had respiratory failure due to pneumonia. Other causes included atelectasis accompanied by pleural effusion (24.2%) and pleural effusion (23.2%). Ninety-seven patients had no pulmonary complications. The mortality rate was 6.4% within the first visit and 8.7% within the second visit.

CONCLUSIONS

Pneumonia, atelectasis, and pleural effusion can cause respiratory failure within the first month after liver transplant. Early pulmonary examination, diagnosis, and treatment can improve patient survival.

Postoperative Pulmonary Complications After Liver Transplantation: Assessment of Risk Factors for Mortality

BACKGROUND

The aim of this study was to identify the risk factors related to mortality in liver transplant (LT) patients with post-transplantation pulmonary complications.

METHOD

Patients who underwent liver transplantation in our clinic between January 2010 and January 2012 were retrospectively reviewed for post-transplantation pulmonary complications. Demographic, clinical, radiologic, and postoperative chart data of 153 patients with pulmonary complications were analyzed using an independent samples Student t test, Pearson's χ(2) test, Fisher's exact test, and Yate's corrected χ(2) test. Mortality was analyzed using a multiple logistic regression model. The best-fit breakpoint resulting in a cut-off value for the variables of interest was determined using ROC curves and the Youden index.

RESULTS

The 153 patients with pulmonary complication were divided into 2 groups: mortality (n = 53) and survival (n = 100). Univariate analyses showed significant differences between these 2 groups with respect to MELD score (P = .035), duration of mechanical ventilation (P > .001), pneumonia (P = .01), and endotracheal culture results (P = .001). In the multivariate analysis, hemoglobin (P = .03, odds ratio [OR]: 1.239), MELD score (P = .027, OR: 1.064), duration of mechanical ventilation (P = .003, OR: 1.091), and age (P = .042, OR: 1.001) were significant risk factors for mortality. The best-fit breakpoint analysis yielded cut-off values for hemoglobin (>11.2, sensitivity: 50.9%, specificity: 70%), MELD score (>16, sensitivity: 73.6%, specificity: 42%) and duration of mechanical ventilation (>3, sensitivity: 62.3%, specificity: 76%).

CONCLUSION

Advanced age, high hemoglobin level, high MELD score, and long-term mechanical ventilation are significant risk factors for mortality in liver transplant patients with postoperative pulmonary complications.

Progressive lung calcification after orthotopic heart transplant

Focal, asymmetrical pulmonary airspace opacities in post-transplant setting are commonly from infection, hemorrhage, edema or infarction. Rarely, stable or mildly progressive dense pulmonary opacities are due to pulmonary calcifications. In the majority of cases, these are asymptomatic and warrant no further intervention.

Diaphragmatic hernia in infants following living donor liver transplantation: report of three cases and a review of the literature

DH is a rare complication following LT. This report presents three cases of right-sided DH after LT using a left-sided graft. All of the patients were younger than one yr of age, and they were critically ill owing to their original disease, characterized by biliary atresia, progressive familiar intrahepatic cholestasis, and acute liver failure. DH occurred with sudden onset within three months after LT. All of the cases were promptly diagnosed and treated. A literature review of 24 cases of DH identified four factors associated with DH: left-sided graft, right-sided DH, relatively delayed onset of DH, and age-specific chief complaint. DH following LT should be considered as a potential surgical complication when a left-sided graft is used, especially in small infants with coagulopathy and malnutrition.

Posteromedial diaphragmatic hernia following pediatric liver transplantation

Diaphragmatic hernia is a rare complication following pediatric LT. Here, four children who developed right-sided posteromedial diaphragmatic hernias after LT are reported. The primary disease was biliary atresia in two patients, hemangioendothelioma in one, and angiosarcoma in one patient. All of the patients underwent living-donor LT using a left lateral graft. The patients presented with abdominal and/or pulmonary signs and symptoms. The diaphragmatic hernias were diagnosed at 28 days to seven months post-transplant by standard radiographs or chest CT. The defects were located at the posteromedial aspect of the diaphragm and were closed by primary closure. After diaphragm repair, the post-operative course was unremarkable and there were no recurrences. Thermal or mechanical injuries to the bare area, especially in cases of excessive adhesion between the liver and diaphragm after Kasai operation, were the possible causes of the posteromedial diaphragmatic hernia after pediatric LT.

Multidrug-resistant gram-negative bacterial infections after liver transplantation - spectrum and risk factors

OBJECTIVES

Gram-negative bacilli infections, especially multidrug-resistant gram-negative bacilli infections, are the leading cause of high mortality after liver transplantation. This study sought to investigate the type of infection, infection rate, pathogenic spectrum, antibiotic-resistance profile, risk factors, and epidemiology of multidrug-resistant gram-negative bacterial infection.

METHODS

A retrospective cohort study was conducted and data of 217 liver transplant patients receiving cadaveric livers between January 2007 and April 2010 were analyzed. Antibiotic susceptibility was determined by minimum inhibitory concentration test. Extended-spectrum and metallo-β-lactamase assays were used to analyze β-lactamase-produced isolates, and repetitive-sequence polymerase chain reaction was used to differentiate bacterium subspecies.

RESULTS

Sixty-seven isolates of multidrug-resistant gram-negative bacteria were isolated from 66 infected liver transplant patients. Stenotrophomonas maltophilia (100%, 8/8), Klebsiella pneumoniae (61.5%, 8/13), Enterobacter cloacae (75%, 3/4) and Escherichia coli (81.3%, 13/16) were the most common extended-spectrum β-lactamase-producing bacilli. Metallo-β-lactamase expressing isolates were identified as S. maltophilia (100%, 8/8), Pseudomonas aeruginosa (83.3%, 5/6), Acinetobacter baumannii (95%, 19/20). Significant independent risk factors for multidrug-resistant gram-negative infection were extended use of pre-transplant broad-spectrum antibiotics (OR 9.027, P=0.001) and prolonged (≧72h) endotracheal intubation (OR 3.537, P=0.033).

CONCLUSIONS

To reduce the risk of acquiring MDR gram-negative bacillus infections after liver transplant, control measures are required to limit the use of prophylactic antibiotic in preventing infection during liver transplant and to shorten endotracheal intubation time.

Right-sided diaphragmatic hernia after orthotopic liver transplantation: report of two cases

Diaphragmatic hernia after OLT is a rare surgical complication. We here report successful diagnosis and treatment of two cases with right-sided diaphragmatic hernia developed after OLT both utilizing left-sided allografts. Combination of factors related to the surgical techniques and patient characteristics might explain the pathophysiology behind the diaphragmatic hernias following liver transplantation. Respiratory as well as non-specific gastrointestinal symptoms may be hints for an overlooked diaphragmatic hernia after liver transplantation. Diaphragmatic hernia should be added to the list of potential complications of liver transplantation for prompt diagnosis and appropriate treatment.

Hepatopulmonary syndrome: use of extracorporeal life support for life-threatening hypoxia following liver transplantation

Hepatopulmonary syndrome is an uncommon complication of nonacute liver failure, and in rare cases, hypoxia may be the presenting sign of liver dysfunction. The condition, once thought to be a contraindication, is improved in most cases by transplantation. There is a significant risk of postoperative, hypoxia-related morbidity and mortality in patients with hepatopulmonary syndrome. We present a case of life-threatening hypoxia following liver transplantation for liver failure and associated hepatopulmonary syndrome, with successful management using extracorporeal membrane oxygenation.

Bowel obstruction due to diaphragmatic hernia in an elder child after pediatric liver transplantation

A 10-yr-old boy with end-stage liver cirrhosis due to Wilson's disease received a living donor liver transplantation (LDLT) at our institution. The donor was his father and the graft was a left lateral segment. The liver transplantation procedure and the postoperative course were uneventful. Two months after the procedure, he developed a first episode of bowel obstruction that was treated with conservative therapy. During a second episode of bowel obstruction, he also presented respiratory distress. A plain chest X-ray revealed the presence of small intestine loops in the right thoracic cavity and bowel obstruction due to diaphragmatic hernia was diagnosed. Repair of the diaphragmatic hernia was performed and the patient has been doing well after the surgery. Diaphragmatic hernia after LDLT is rare but should be recognized as a possible complication when a left lobe or a left lateral segment graft is used.

Progressive pulmonary calcification in a child after orthotopic liver transplantation

We present a case of progressive pulmonary calcification associated with prolonged respiratory insufficiency in a 2-year-old boy with a history of orthotopic liver transplantation. This case demonstrates the potentially progressive nature of pulmonary calcification and that it can present with respiratory insufficiency at a later period after transplantation than previously thought. We describe radiological findings and discuss established as well as plausible pathological mechanisms contributing to the development of calcifications in these patients.

Immediate Extubation of Children Following Liver Transplantation Is Safe and May Be Beneficial

BACKGROUND

Immediate tracheal extubation of selected adult patients after orthotopic liver transplant (OLT) is common practice. We hypothesized that selected children may be safely extubated immediately after OLT and avoid potentially deleterious effects of artificial ventilation and sedation.

METHODS

After June 2002, we chose immediate extubation unless a specific contraindication was identified. Charts of all children undergoing OLT between June 2002 and February 2005 were reviewed to audit safety and outcome of this approach. Comparative data were obtained for children undergoing first elective OLT at other UK centers.

RESULTS

Forty-six cadaveric liver transplants were performed in 40 patients: 26 of 34 (76%) elective transplants and 4 of 12 (33%) urgent transplants were extubated immediately after surgery. Eight of 14 (57%) children weighing less than 10 kg were successfully extubated. One child required reintubation after developing transfusion-related acute lung injury. There were no other events compromising patient or graft. Small recipient size, split/reduced grafts, preexisting respiratory disease, retransplantation, and acute liver failure did not individually preclude successful immediate extubation. After elective OLT, the mean duration of intensive care stay was significantly shorter in the extubated group than in those who were ventilated (2.5 vs. 6.1 days, P<0.01). All children receiving a liver transplant at other UK centers in 2003 were ventilated postoperatively. However, the median duration of intensive care stay (2 days) was the same as in our series.

CONCLUSIONS

Immediate extubation of selected children after OLT is safe. It may enhance patient recovery, benefit graft physiology, and reduce intensive care requirement.

Right-sided diaphragmatic hernia in infants after liver transplantation

Liver transplantation is just as successful in infants as in older children, but more challenging. This relates to the low weight of the recipients and to their rapidly deteriorating clinical condition (malnutrition and end-stage liver disease) ( J Pediatr 1990;117:205-210; BMJ 1993;307:825-828; Ann Surg 1996;223:658-664; Transplantation 1997;64:242-248; J Pediatr Surg 1998;33:20-23). In addition, higher rates of diaphragmatic complications have been shown to significantly correlate with a younger age ( Transplantation 2002;73:228-232; Transpl Int 1998;11:281-283; Pediatr Transplant 2000;4:39-44), but diaphragmatic hernia has never been reported as a complication of liver transplantation. In this report, 2 patients who developed diaphragmatic hernia after liver transplantation are presented. The possible role of several contributing factors resulting in diaphragmatic hernia is discussed. These factors include (1) diaphragm thinness related to low weight and malnutrition, (2) direct trauma at operation (dissection and diathermy), (3) increased abdominal pressure after transplantation caused by the use of a slightly oversized liver graft, and (4) the medial positioning of the partial liver graft in the abdomen.

Risk factors for postoperative respiratory complications in adult liver transplant recipients

To determine the types and the incidence of as well as risk factors for early postoperative (<30 days) respiratory complications in adult liver transplant (LT) recipients, we reviewed The data of 44 consecutive adult LT recipients who received their grafts from January 1995 through December 2002. The data included demographic features; primary diagnosis; number of intraoperative transfusions; preoperative and postoperative laboratory values; intraoperative and postoperative characteristics; and early postoperative (<30 days) mortality. Pulmonary atelectasis, pleural effusion, pneumonia, respiratory failure, and pulmonary edema were the respiratory complications investigated. Twenty-six patients (59.1%) developed at least one respiratory complication during the early postoperative period. The most frequent complication was pleural effusion (n = 18, 40.9%), followed by atelectasis (n = 13, 29.5%), pneumonia (n = 10, 22.7%), acute respiratory failure (n = 5, 11.4%), pulmonary edema (n = 3, 6.8%), and pneumothorax (n = 2, 4.5%). Compared to the patients who did not develop these problems, the affected cohort was significantly older (27 +/- 12 years vs 36 +/- 14 years, respectively; P =.039) and required more intraoperative transfusions (P =.005). Among the overall mortality rate of 15.9%, patients who developed pneumonia showed a significantly higher mortality (40.0% vs 8.8%, respectively; P =.037). Pleural effusion, atelectasis, and pneumonia are the main respriatory complications that occur in adult LT recipients. Patient age and intraoperative transfusion requirements are important predictors of early postoperative complications. Pneumonia is associated with a poor prognosis in this patient group.

Early postoperative complications in recipients of living donor liver transplantation

PURPOSE

Complications are common in the early postoperative period after living donor liver transplantation (LDLT). The aims of this analysis were to describe and identify risk factors for early postoperative complications.

METHODS

Between June 1994 and June 2003, 140 consecutive LDLT patients were divided into 3 groups: group I was small infants <9 kg (n = 30); group II, pediatric patients (n = 63); and group III, adult patients (n = 47). The complications within 3 months after operation were analyzed.

RESULTS

The mortality rate was 1.4%. Surgical complications requiring relaparotomy occurred in 7.9% of patients. Intraoperative portal vein thrombosis requiring immediate thrombectomy, which occurred in 10 patients, was significantly more frequent in the small infant group (23.1% vs 3.2% vs 2.1%; P < .01). Acute hepatic artery thrombosis that occurred in 2 patients was remedied successfully using operative rearterilization. Hepatic outflow obstruction requiring radiological interventions developed in 5 subjects. Medical complications included the following: pulmonary (14.3%), renal (19.3%), bacteremia (10.7%), cytomegalovirus infection (9.3%), and drain-related infections (20.7%). The incidence of hospital-acquired renal insufficiency was significantly higher in adult patients (3.3% vs 14.3% vs 36.2%; P < .01). There was no significant difference in the incidence of acute cellular rejection between members of the 3 groups (10.0% vs 17.5% vs 17%; P = .63).

CONCLUSIONS

Sophisticated postoperative care with multiple disciplinary involvements may achieve a low early mortality rate in LDLT. Small infants weighing <9 kg may carry a greater risk of intraoperative portal vein thrombosis. Pulmonary complications and renal function impairments were the most troublesome in pediatric and adult recipients, respectively.

Repeated detection of gas in the portal vein after liver transplantation: A sign of EBV-associated post-transplant lymphoproliferation?

A 1-yr-old child presented with intractable right sided pleural effusion and progressive clinical deterioration 3 weeks after liver transplantation for Alagille Syndrome. He had been treated successfully for severe acute rejection before. Ultrasound and Doppler mode studies repeatedly demonstrated air in the portal vein. Intra-abdominal and intra-thoracic lymphoproliferation was detected, and EBV virus load and serology were suggestive of primary EBV infection. Liver biopsy revealed blast-like infiltrates of B-cells, considered diagnostic for post-transplant lymphoproliferative disease. The disease resolved upon reduction of immunosuppression. We suggest that the detection of portal vein gas in pediatric liver transplant recipients beyond the early post-operative period may be a sign of intra-abdominal post-transplant lymphoproliferative disease.

Thoracic radiology in kidney and liver transplantation

Renal transplantation accounts for more than half of all solid organ transplants performed in the U.S., and the liver is the second most commonly transplanted solid organ. Although abdominal imaging procedures are commonplace in these patients, there has been relatively little attention paid to thoracic imaging applications. Preoperative imaging is crucial to aid in the exclusion of infectious or malignant disease. In the perioperative time period, thoracic imaging focuses both on standard intensive care unit care, including monitoring devices and their complications, and on the early infections that can occur. Postoperative management is divided into three time periods, and the principles governing the occurrence of infections and malignancies are reviewed. Anatomic and pathologic aspects unique to kidney and liver transplantation patients are also discussed.

Diaphragmatic dysfunction after pediatric orthotopic liver transplantation

BACKGROUND

Pediatric orthotopic liver transplantation (OLT) has a low mortality. Some children, however, have an adverse outcome defined as a prolonged ventilatory support requirement and protracted pediatric intensive care unit (PICU) stay. The aim of this study was to determine if that adverse outcome related to the child's condition pre-OLT and/or the development of a pleural effusion or diaphragmatic dysfunction.

METHODS

The study included 210 children with a median age at transplantation of 45.5 months (range 0.2-252 months). Fourteen had undergone retransplantation. The duration of ventilatory support (intermittent positive pressure ventilation [IPPV]) and PICU admission and development of a pleural effusion and/or diaphragmatic dysfunction were documented for each child. The patients were divided into three groups according to whether they had acute liver failure (ALF), chronic liver disease at home (CHOM), or chronic liver failure sufficiently ill to be in the hospital awaiting transplantation (CHOSP).

RESULTS

The 36 children with ALF were of similar age to the 138 CHOM and 36 CHOSP children but required longer IPPV (P<0.0001) and PICU stay (P<0.0001). Overall, 17 children developed diaphragmatic dysfunction and 138 pleural effusions; affected children required longer IPPV and PICU stay (P<0.01). Regression analysis demonstrated that diaphragmatic dysfunction, but not pleural effusion development, was associated with prolonged ventilation (P<0.01) and protracted PICU stay (P<0.05). Other risk factors were ALF (P<0.01), retransplantation (P<0.01), and young age (P<0.05).

CONCLUSION

Diaphragmatic dysfunction adversely influences PICU morbidity after OLT. Early assessment of diaphragmatic function, and if necessary aggressive management, might improve outcome.