Pulmonary complications in patients receiving a solid-organ transplant:

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.

Factors associated with pulmonary infection in kidney and kidney-pancreas transplant recipients: a case-control study

OBJECTIVE

To evaluate the etiology of and factors associated with pulmonary infection in kidney and kidney-pancreas transplant recipients.

METHODS

This was a single-center case-control study conducted between December of 2017 and March of 2020 at a referral center for kidney transplantation in the city of Belo Horizonte, Brazil. The case:control ratio was 1:1.8. Cases included kidney or kidney-pancreas transplant recipients hospitalized with pulmonary infection. Controls included kidney or kidney-pancreas transplant recipients without pulmonary infection and matched to cases for sex, age group, and donor type (living or deceased).

RESULTS

A total of 197 patients were included in the study. Of those, 70 were cases and 127 were controls. The mean age was 55 years (for cases) and 53 years (for controls), with a predominance of males. Corticosteroid use, bronchiectasis, and being overweight were associated with pulmonary infection risk in the multivariate logistic regression model. The most common etiologic agent of infection was cytomegalovirus (in 14.3% of the cases), followed by Mycobacterium tuberculosis (in 10%), Histoplasma capsulatum (in 7.1%), and Pseudomonas aeruginosa (in 7.1%).

CONCLUSIONS

Corticosteroid use, bronchiectasis, and being overweight appear to be risk factors for pulmonary infection in kidney/kidney-pancreas transplant recipients, endemic mycoses being prevalent in this population. Appropriate planning and follow-up play an important role in identifying kidney and kidney-pancreas transplant recipients at risk of pulmonary infection.

Liver Transplantation in Acute-on-Chronic Liver Failure: Excellent Outcome and Difficult Posttransplant Course

Background

Acute-on-chronic liver failure (ACLF) patients have high mortality in a short period of time. This study aimed to compare the prognosis of transplanted ACLF patients to that of nontransplanted ACLF patients and decompensated cirrhosis recipients.

Methods

Clinical data of 29 transplanted ACLF patients, 312 nontransplanted ACLF patients, and 60 transplanted decompensated cirrhosis patients were retrospectively collected. Propensity score matching (PSM) analysis was used to match patients between different groups.

Results

After PSM, the 90-day and 1-year survival of transplanted ACLF patients was significantly longer than that of nontransplant controls. Although the 90-day survival and 1-year survival of ACLF recipients was similar to that of decompensated cirrhosis controls, ACLF recipients were found to have longer mechanical ventilation, longer intensive care unit (ICU) stay, longer hospital stay, higher incidence of tracheotomy, higher expense, and higher morbidity of complication than matched decompensated cirrhosis controls. The 90-day and 1-year survival of transplanted ACLF grade 2–3 patients was also significantly longer than that of nontransplanted controls.

Conclusions

Liver transplantation can strongly improve the prognosis of ACLF patients. Despite having more burdens (including longer mechanical ventilation, longer ICU stay, higher incidence of tracheotomy, longer hospital stay, higher hospitalization expense, and higher complication morbidity), ACLF recipients can obtain similar short-term and long-term survival to decompensated cirrhosis recipients. For severe ACLF patients, liver transplantation can also significantly improve their short-term and long-term survival.

Comparison of the effects of neostigmine and sugammadex on postoperative residual curarization and postoperative pulmonary complications by means of diaphragm and lung ultrasonography: a study protocol for prospective double-blind randomized controlled trial

Background

Postoperative residual curarization (PORC) may be a potential risk factor of postoperative pulmonary complications (PPCs), and both of them will lead to adverse consequences on surgical patient recovery. The train-of-four ratio (TOFr) which is detected by acceleromyography of the adductor pollicis is thought as the gold standard for the measurement of PORC. However, diaphragm function recovery may differ from that of the peripheral muscles. Recent studies suggested that diaphragm ultrasonography may be useful to reveal the diaphragm function recovery, and similarly, lung ultrasound was reported for the assessment of PPCs in recent years as well. Sugammadex reversal of neuromuscular blockade is rapid and complete, and there appear to be fewer postoperative complications than with neostigmine. This study aims to compare the effects of neostigmine and sugammadex, on PORC and PPCs employing diaphragm and lung ultrasonography, respectively.

Methods/design

In this prospective, double-blind, randomized controlled trial, patients of the American Society of Anesthesiologists Physical Status I–III, aged over 60, will be enrolled. They will be scheduled to undergo arthroplasty under general anesthesia. All patients will be allocated randomly into two groups, group NEO (neostigmine) and group SUG (sugammadex), using these two drugs for reversing rocuronium. The primary outcome of the study is the incidence of PPCs in the NEO and SUG groups. The secondary outcomes are the evaluation of diaphragm ultrasonography and lung ultrasound, performed by an independent sonographer before anesthesia, and at 10 min and 30 min after extubation in the post-anesthesia care unit, respectively.

Discussion

Elimination of PORC is a priority at the emergence of anesthesia, and it may be associated with reducing postoperative complications like PPCs. Sugammadex was reported to be superior to reverse neuromuscular blockade than neostigmine. Theoretically, complete recovery of neuromuscular function should be indicated by TOFr > 0.9. However, the diaphragm function recovery may not be the same matter, which probably harms pulmonary function. The hypothesis will be proposed that sugammadex is more beneficial than neostigmine to reduce the incidence of PPCs and strongly favorable for the recovery of diaphragm function in our study setting.

Trial registration

ClinicalTrials.gov NCT05040490. Registered on 3 September 2021

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06328-3.

Impact on grafted kidney function of rocuronium-sugammadex vs cisatracurium-neostigmine strategy for neuromuscular block management. An Italian single-center, 2014-2017 retrospective cohort case-control study

Background

The impact of sugammadex in patients with end-stage renal disease undergoing kidney transplantation is still far from being defined. The aim of the study is to compare sugammadex to neostigmine for reversal of rocuronium- and cisatracurium-induced neuromuscular block (NMB), respectively, in patients undergoing kidney transplantation.

Methods

A single-center, 2014-2017 retrospective cohort case-control study was performed. A total of 350 patients undergoing kidney transplantation, equally divided between a sugammadex group (175 patients) and a neostigmine group (175 patients), were considered. Postoperative kidney function, evaluated by monitoring of serum creatinine and urea and estimated glomerular filtration rate (eGFR), was the endpoint. Other endpoints were anesthetic and surgical times, post-anesthesia care unit length of stay, postoperative intensive care unit admission, and recurrent NMB or complications.

Results

No significant differences in patient or, with the exception of drugs involved in NMB management, anesthetic, and surgical characteristics, were observed between the two groups. Serum creatinine (median [interquartile range]: 596.0 [478.0-749.0] vs 639.0 [527.7-870.0] μmol/L, p = 0.0128) and serum urea (14.9 [10.8-21.6] vs 17.1 [13.1-22.0] mmol/L, p = 0.0486) were lower, while eGFR (8.0 [6.0-11.0] vs 8.0 [6.0-10.0], p = 0.0473) was higher in the sugammadex group than in the neostigmine group after surgery. The sugammadex group showed significantly lower incidence of postoperative severe hypoxemia (0.6% vs 6.3%, p = 0.006), shorter PACU stay (70 [60-90] min vs 90 [60-105] min, p < 0.001), and reduced ICU admissions (0.6% vs 8.0%, p = 0.001).

Conclusions

Compared to cisatracurium-neostigmine, the rocuronium-sugammadex strategy for reversal of NMB showed a better recovery profile in patients undergoing kidney transplantation.

Posttransplant Pneumonia Among Solid Organ Transplant Recipients Followed in Intensive Care Unit

OBJECTIVES

Pneumonia is a significant cause of morbidity and mortality in solid-organ transplant recipients. We studied the demographic characteristics, respiratory management, and outcomes of solid-organ transplant recipients with pneumonia in an intensive care unit.

MATERIALS AND METHODS

There have been 2857 kidney, 687 liver, and 142 heart transplants performed between October 16, 1985, and February 28, 2021, at our center. We retrospectively analyzed records for 51 of 193 recipients with pneumonia during the posttransplant period between January 1, 2016, and December 31, 2018.

RESULTS

Fifty-one of 193 recipients were followed in the intensive care unit. Mean age was 45.4 ± 16.6 years among 42 male (82.4%) and 9 female (17.6%) recipients. Twenty-six patients (51%) underwent kidney transplant, 14 (27.5%) liver transplant, 7 (13.7%) heart transplant, and 4 (7.8%) combined kidney and liver transplant. Most pneumonia episodes occurred 6 months after transplant (70.6%) with acute hypoxemic respiratory failure. Mean Acute Physiology and Chronic Health Evaluation System II score was 18.9 ± 7.7, and the Sequential Organ Failure Assessment score was 8.5 ± 3.9 at intensive care unit admission. Whereas 66.7% of pneumonia cases were nosocomial acquired, 33.3% were community acquired. The intensive care unit and 28-day mortality rates were 39.2% and 64.7%, respectively.

CONCLUSIONS

Solid-organ transplant recipients with pneumonia have been associated with poor prognosis. Our cohort followed in the intensive care unit comprised mostly patients with nosocomial pneumonia with acute hypoxemic respiratory failure, hospitalized 6 months after transplant with high Acute Physiology and Chronic Health Evaluation System II scores predictive of mortality. In this high-risk patient group, careful follow-up, early discovery of warning signs, and rapid treatment initiation could improve the outcomes in the intensive care unit.

Etiologies and Outcomes of Acute Respiratory Failure in Solid Organ Transplant Recipients: Insight Into the EFRAIM Multicenter Cohort

BACKGROUND

Respiratory complications of solid organ transplant (SOT) are a diagnostic and therapeutic challenge when requiring intensive care unit (ICU) admission. We aimed at describing this challenge in a prospective cohort of SOT recipients admitted in the ICU.

METHODS

In this post hoc analysis of an international cohort of immunocompromised patients admitted in the ICU for an acute respiratory failure, we analyzed all SOT recipients and compared their severity, etiologic diagnosis, prognosis, and outcome according to the performance of an invasive diagnostic strategy (encompassing a fiber-optic bronchoscopy and bronchoalveolar lavage), the type of transplanted organ, and the need of invasive ventilation at day 1.

RESULTS

Among 1611 patients included in the primary study, 142 were SOT recipients (kidney, n = 73; 51.4%; lung, n = 33; 23.2%; liver, n = 29; 20.4%; heart, n = 7; 4.9%). Lung transplant recipients were younger than other SOT recipients, and severity did not differ across type of received organ. An invasive diagnostic strategy was more frequently performed in lung transplant recipients with a trend toward a higher rate of bacterial etiology in lung than kidney transplant recipients. Overall ICU survival of SOT recipients was 75.4%. Invasive diagnostic strategy, type of transplanted organ, and need of invasive mechanical ventilation at day 1 did not affect ICU prognosis.

CONCLUSIONS

ICU management of hypoxemic acute respiratory failure in SOT recipients translated into a low ICU mortality rate, whatever the transplanted organ or the acute respiratory failure cause. The post-ICU burden of acute respiratory failure SOT recipients remains to be investigated.

Acute Respiratory Failure in Renal Transplant Recipients: A Single Center Experience

OBJECTIVES

We evaluated the frequency and cause of acute respiratory failure in renal transplant recipients.

MATERIALS AND METHODS

Our single-center retrospective observational study included consecutive renal transplant recipients who were admitted to an intensive care unit for acute respiratory failure between 2011 and 2017. Acute respiratory failure was defined as oxygen saturation < 92% or partial pressure of oxygen in arterial blood < 60 mm Hg on room air and/or requirement of noninvasive or invasive mechanical ventilation.

RESULTS

Of 187 renal transplant recipients, 35 (18.71%) required intensive care unit admission; 11 of these patients (31.4%) were admitted to the intensive care unit with acute respiratory failure. Six of these patients (54.5%) had pneumonia and had shown infiltrates on chest radiography, which were shown in a minimum of 3 zones of the lung (2 with Klebsiella pneumonia, 1 with Acinetobacter species, 1 with Proteus mirabilis, 2 with no microorganisms). The other reasons for acute respiratory failure were cardiogenic pulmonary edema (2 patients), acute respiratory distress syndrome (2 patients, due to acute pancreatitis and acute cerebrovascular thromboembolism), and exacerbation of chronic obstructive pulmonary disease (1 patient). Six patients (54.5%) needed invasive mechanical ventilation because of pneumonia (3 patients), cardiogenic pulmonary edema (2 patients), and cerebrovascular thromboembolism (1 patient). Hemodialysis was administered in 5 patients (45%). Six of 11 patients died due to pneumonia (3 p atients), cardiogenic pulmonary edema (2 patients), and cerebrovascular thromboembolism (1 patient). Among the 5 survivors, 3 (60%) had recovered previous graft function.

CONCLUSIONS

Acute respiratory failure is associated with high mortality and morbidity in renal transplant recipients. Main causes of acute respiratory failure were bacterial pneumonia and cardiogenic pulmonary edema in our study population. Extended chemoprophylaxis for bacterial and fungal infection and early intensive care unit admission of patients with acute respiratory failure may improve outcomes.

Postoperative Risk Factors and Outcome of Patients With Liver Transplantation Who Were Admitted to Pediatric Intensive Care Unit: A 10-Year Single-Center Review in China

INTRODUCTION

The aim of this study was to present our 10-year experience of pediatric intensive care unit (PICU) management with pediatric liver recipients and to understand the importance of close interdisciplinary cooperation in 2 hospitals.

METHODS

A retrospective chart review study was performed according to our hospital's medical records and the pediatric liver transplant database of Renji hospital.

RESULTS

A total of 767 patients received liver transplantation (LT) performed in Renji hospital between October 2006 and December 2016, of which 97 of them were admitted to PICU in our center for various complications developed after transplantation. 8.8% (16/208) and 14.4% (81/559) of patients were transferred to PICU in stages I and II, respectively, and was comparable in the 2 stages (P = .017). The majority of patients was late postoperative children (median 185 post-LT days) in stage I. More patients were transferred to PICU directly in stage II. PICU admitted more younger (median 8.2 months) and early postoperative patients in stage II. The median length of PICU stay was 11.0 (6.0-20.5) days. The median length of mechanical ventilation was 5.0 (0.0-12.0) days. The most frequent complications were pulmonary complications (52 [53.6%] patients), surgical complications (22 [22.7%] patients), sepsis (7 [7.2%]), and other miscellaneous complications (16 [16.5%] patients). The overall 28-day PICU mortality was 25.8% (n = 25) and 64.0% (n = 16) of the deaths happened in the early postoperative period. There was significant difference concerning mortality in children with surgical complications and medical problems (54.5% [12/22] vs 17.3% [13/75], P = .001). Multivariate analysis by regression showed that the pediatric risk of mortality III score was the only independent prognostic factor (P = .031).

CONCLUSIONS

Multiple complications occur in children with LT. Although challenging, interdisciplinary cooperation between different hospitals is an effective mean to enable children to maximize the benefit gained from LT in China.

Diagnostic and therapeutic approach to infectious diseases in solid organ transplant recipients

Purpose

Prognosis of solid organ transplant (SOT) recipients has improved, mainly because of better prevention of rejection by immunosuppressive therapies. However, SOT recipients are highly susceptible to conventional and opportunistic infections, which represent a major cause of morbidity, graft dysfunction and mortality.

Methods

Narrative review.

Results

We cover the current epidemiology and main aspects of infections in SOT recipients including risk factors such as postoperative risks and specific risks for different transplant recipients, key points on anti-infective prophylaxis as well as diagnostic and therapeutic approaches. We provide an up-to-date guide for management of the main syndromes that can be encountered in SOT recipients including acute respiratory failure, sepsis or septic shock, and central nervous system infections as well as bacterial infections with multidrug-resistant strains, invasive fungal diseases, viral infections and less common pathogens that may impact this patient population.

Conclusion

We provide state-of the art review of available knowledge of critically ill SOT patients with infections.

The Incidence and Risk Factors of Low Oxygenation After Orthotropic Liver Transplantation

Background

This study was designed to observe incidence and risk factors of low oxygenation after orthotropic liver transplantation (OLT).

Material/Methods

We retrospectively evaluated all adult patients who underwent living-donor OLT between January 1, 2017 and December 31, 2017. Postoperative low oxygenation was defined as PaO₂/FiO₂ <300 mmHg within 24 hours after surgery. Early acute kidney injury (AKI) after OLT was also defined when AKI was happened with 24 hours after operative.

Results

A total of 301 patients, aged 50.35±10.29 years were enrolled. Of these patients, 100 patients (33.2%) suffered postoperative low oxygenation (PaO₂/FiO₂=251.80±35.84). Compared with the normal oxygenation group, body mass index (BMI) (24.48±3.53 versus 23.1±3.27 kg/m², P=0.001), preoperative hemoglobin (115.79±29.27 versus 111.52±29.80 g/L, P=0.033), preoperative MELD (22.25±6.54 versus 20.24±5.74, P=0.008), and intraoperative urinary volume (1.25 [0.76, 1.89] versus 2.04 [1.49, 3.68] mL/kg/h, P=0.003) were higher in low oxygenation group. There were more cases of earlier AKIs that occurred after OLT in low oxygenation patients than that in normal group (47% versus 23.4%, P<0.001). Logistic analysis showed that the preoperative BMI (hazard ration [HR]=1.107, [1.010, 1.212], P=0.029) and early AKI after OLT (HR=2.115, [1.161, 3.855], P=0.014) were independent risk factors for postoperative low oxygenation.

Conclusions

The incidence of postoperative low oxygenation after liver transplantation in adults was 33.2%. BMI and early AKI after OLT were correlated with postoperative hypoxemia.

Perioperative Goal-Directed Therapy during Kidney Transplantation: An Impact Evaluation on the Major Postoperative Complications

Background: Kidney transplantation is considered the first-choice therapy in end-stage renal disease (ESRD) patients. Despite recent improvements in terms of outcomes and graft survival in recipients, postoperative complications still concern the health-care providers involved in the management of those patients. Particularly challenging are cardiovascular complications. Perioperative goal-directed fluid-therapy (PGDT) and hemodynamic optimization are widely used in high-risk surgical patients and are associated with a significant reduction in postoperative complication rates and length of stay (LOS). The aim of this work is to compare the effects of perioperative goal-directed therapy (PGDT) with conventional fluid therapy (CFT) and to determine whether there are any differences in major postoperative complications rates and delayed graft function (DGF) outcomes. Methods: Prospective study with historical controls. Two groups, a PGDT and a CFT group, were used: The stroke volume (SV) optimization protocol was applied for the PGDT group throughout the procedure. Conventional fluid therapy with fluids titration at a central venous pressure (CVP) of 8–12 mmHg and mean arterial pressure (MAP) >80 mmHg was applied to the control group. Postoperative data collection including vital signs, weight, urinary output, serum creatinine, blood urea nitrogen, serum potassium, and assessment of volemic status and the signs and symptoms of major postoperative complications occurred at 24 h, 72 h, 7 days, and 30 days after transplantation. Results: Among the 66 patients enrolled (33 for each group) similar physical characteristics were proved. Good functional recovery was evident in 92% of the CFT group, 98% of the PGDT group, and 94% of total patients. The statistical analysis showed a difference in postoperative complications as follows: Significant reduction of cardiovascular complications and DGF episodes (p < 0.05), and surgical complications (p < 0.01). There were no significant differences in pulmonary or other complications. Conclusions: PGDT and SV optimization effectively influenced the rate of major postoperative complications, reducing the overall morbidity and thus the mortality in patients receiving kidney transplantation.

Early Bacterial Pneumonia After Hepatic Transplantation: Epidemiologic Profile

BACKGROUND

Postoperative pulmonary complications are major cause of morbidity and mortality in patients receiving liver transplantation (LT), particularly bacterial pneumonia occurring within the first 100 days after transplantation. Our aim in this study was to determine the incidence, microorganisms involved, associated factors, and morbidity of bacterial pneumonia presenting in the first 100 days posttransplant.

METHODS

We performed a cohort study in which patients receiving liver transplantation were included prospectively in our national database (Database of Infections in Transplantation of Solid Organs). The study period was from July 14, 2009 to July 24, 2015.

RESULTS

One hundred six patients were transplanted during the 6-year period. We documented 9 bacterial pneumonia cases with an incidence of 8.5 per 100 patients; 2 patients had hospital-acquired pneumonia (HAP) and 7 had ventilator-associated pneumonia (VAP). In 4 of the 9 bacterial pneumonia cases, patients presented with bacteremia. Eleven microorganisms were isolated these 9 patients. Microbiologic diagnosis methods included 5 cases of alveolar bronchoalveolar lavage (BAL), 1 case of BAL and pleural fluid puncture, 1 case of pleural fluid puncture, and 1 case through sputum study. Of the 11 isolated organisms, 9 corresponded to Gram-negative bacilli (GNB): Klebsiella spp, n = 3; Acinetobacter baumannii, n = 4; Morganella morganii, n = 1; and Pseudomonas aeruginosa, n = 1. Regarding the resistance profile, 7 presented with a multiresistance profile (MDR) and extreme resistance (XDR). Univariate analysis identified the Model for End-Stage Liver Disease (MELD) pretransplant score as a factor associated with developing pneumonia (P < .001, 95% confidence interval [CI] 2.872-10.167), and early extubation, before 8 hours posttransplant, as a protective factor (P = .008; relative risk [RR] 0.124; 95% CI 0 .041-0.377). Hospital stay was longer in patients with pneumonia compared to those without pneumonia (P < .0001, 95% CI 17.79-43.11 days). There was also an increased risk of death in patients with pneumonia (RR 17.963; 95% CI 5106-63,195).

CONCLUSIONS

Early bacterial pneumonia after hepatic transplantation is associated with higher morbidity and mortality. At our center, 4 of 9 patients had bacteremia. GNB cases with MDR and XDR profiles are predominant. Early extubation is a protective factor.

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.

Retrospective Comparative Study on Postoperative Pulmonary Complications After Orthotopic Liver Transplantation Using the Melbourne Group Scale (MGS-2) Diagnostic Criteria

Background

Postoperative pulmonary complications (PPCs) after orthotopic liver transplantation (OLT) are associated with poor postoperative survival. However, there are no standard criteria for diagnosis of PPCs. This retrospective study aimed to explore the reliability of the Melbourne Group Scale version 2 (MGS-2) for determining PPCs after OLT.

Material/Methods

A total of 121 patients were divided into 3 groups. In the PPC and non-PPC groups, PPCs were determined to be present or absent in accordance with both the MGS-2 and the conventional broad criteria for diagnosis of PPCs; in the potential-PPC group, PPCs were determined to be present only in accordance with the conventional broad criteria. The perioperative risk factors for PPCs and prognosis of patients in potential-PPC group were all compared with non-PPC groups and PPC groups.

Results

The preoperative characteristics of patients in the potential-PPC group were similar to those in non-PPC group. The length of intensive care unit stay (2.26±0.22 vs. 4.75±0.47 days; P=0.017), duration of hospitalization (33.33±1.70 vs. 48.78±2.53 days; P<0.001), and treatment cost (28.01±1.78 vs. 38.35±1.85×10 000 yuan; P=0.018) were significantly less in the potential-PPC group than in the PPC group. Furthermore, in accordance with the MGS-2 criteria for diagnosis of PPCs, patients with PPCs showed poorer overall survival rates than those without (P=0.038).

Conclusions

The MGS-2 appears to be a more suitable and reliable tool for diagnosis of PPCs and to identify the post-OLT patients with poorer perioperative characteristics and prognosis.

Intensive Care of Pulmonary Complications Following Liver Transplantation

Chronic liver disease has been associated with pulmonary dysfunction both before and after liver transplantation. Post-liver transplantation pulmonary complications can affect both morbidity and mortality often necessitating intensive care during the immediate postoperative period. The major pulmonary complications include pneumonia, pleural effusions, pulmonary edema, and atelectasis. Poor clinical outcomes have been known to be associated with age, severity of liver dysfunction, and preexisting lung disease as well as perioperative events related to fluid balance, particularly transfusion and fluid volumes. Delineating each and every one of these pulmonary complications and their associated risk factors becomes paramount in guiding specific therapeutic strategies.

A systems-based approach to patient care after liver transplantation

Liver transplantation is a cure to many devastating acute and end-stage liver diseases. In the immediate postoperative period, patients are prone to graft, end-organ, and immunosuppressive complications. This article reviews the causes, diagnosis, and treatment of acute postoperative liver transplant complications.

Effect of positive perioperative donor and recipient respiratory bacterial cultures on early post-transplant outcomes in lung transplant recipients

BACKGROUND

It is standard practice to administer prophylactic antibiotics post lung transplantation. However, no studies have evaluated the impact of culture positivity. The purpose of this study was to evaluate early post-transplant outcomes of culture-positive and culture-negative lung transplant (LT) recipients and the appropriateness of the empiric regimens used.

METHODS

Adult patients who received an LT at Emory University Hospital between January 1, 2010 and August 31, 2015 were reviewed and stratified into three groups: (i) culture-positive appropriate empiric treatment, (ii) culture-positive inappropriate empiric treatment, and (iii) culture-negative. Antibiotics were defined as appropriate if bacteria were sensitive to the empiric regimen. The primary endpoint was 30-day mortality. Secondary endpoints included hospital length of stay (LOS), intensive care unit (ICU) LOS, percent neutrophil count in a bronchoalveolar lavage (BAL) sample, presence of airway ischemia, and appropriateness of the empiric antibiotic regimen.

RESULTS

Nine, zero, and four patients died within 30 days in the culture-positive appropriate (n = 113), culture-positive inappropriate (n = 5), and culture-negative groups (n = 29) (P = .564) respectively. The median hospital LOS was 19, 16, and 15 days respectively. Median ICU LOS was 6, 5, and 7 respectively. The respective percent neutrophil counts in the BAL fluid were 79, 83, and 65. The presence of airway ischemia was only documented in eight patients, all in the culture-positive appropriate group.

CONCLUSION

We did not identify an association between antibiotic appropriateness and 30-day mortality, hospital LOS, or ICU LOS in post-LT recipients.

Noninfectious and Infectious Complications and Their Related Characteristics in Heart Transplant Recipients at a National Institute

OBJECTIVES

Complications, which affect the morbidity and mortality of patients after heart transplant, can be divided into infectious and noninfections com-plications. Here, we analyzed both infectious and noninfectious complications and their relation to clinical, laboratory, and surgical characteristics in a Latin American heart transplant population.

MATERIALS AND METHODS

Data were obtained from records of 35 heart transplant patients in the period from 2010 to 2015. Noninfectious and infectious complications were divided into 3 time intervals: within the first month, from month 2 to 6, and after month 6. Relations between complications and clinical, laboratory and surgical variables in different interval times were analyzed.

RESULTS

In our patient group, 70 infectious and 133 noninfectious complications were reported after heart transplant. Infectious complications occurred more often between months 2 and 6 after heart transplant, whereas noninfectious complications occurred more often during the first month. Bacteria were the most common microorganism, and acute graft rejection was the most common noninfectious complication. Moreover, infectious complications were statistically related to 5 factors at month 1 (intraoperative bleeding, normal postsurgery leukocyte level, mild malnutrition, severe malnutrition, and graft rejection), to 3 factors between months 2 and 6 (diabetes mellitus, stage 2 chronic kidney disease, and cryoprecipitate trans-fusions), and to 2 factors after month 6 (prothrombin time and psychologic diagnosis).

CONCLUSIONS

Our results demonstrated that noninfectious complications should be anticipated first in patients after heart transplant. In addition, there are characteristics associated with infectious complications that can be seen during a specific time period.

Noninfectious Pulmonary Complications of Liver, Heart, and Kidney Transplantation: An Update

Despite significant advances in surgical techniques, perioperative care, and immunosuppressive therapy, solid organ transplantation still carries considerable risk of complications. Pulmonary complications, in particular, are a major cause of morbidity and mortality. Although infectious complications prevail, the lungs are also vulnerable to a variety of noninfectious complications related to the transplant surgery and adverse effects of the immunosuppressive regimen. This article focuses on noninfectious pulmonary complications associated with the 3 most commonly performed solid organ transplant procedures: liver, kidney, and heart.

The New Kidney Donor Allocation System and Implications for Anesthesiologists

Given potential disparity and limited allocation of deceased donor kidneys for transplantation, a new federal kidney allocation system was implemented in 2014. Donor organ function and estimated recipient survival in this system has implications for perioperative management of kidney transplant recipients. Early analysis suggests that many of the anticipated goals are being attained. For anesthesiologists, implications of increased dialysis duration and burdens of end-stage renal disease include increased cardiopulmonary disease, challenging fluid, hemodynamic management, and central vein access. With no recent evidence to guide anesthesia care within this new system, we describe the kidney allocation system, summarize initial data, and briefly review organ systems of interest to anesthesiologists. As additional invasive and echocardiographic monitoring may be indicated, one consideration may be development of a dedicated anesthesiology team experienced in management and monitoring of complex patients, in a similar manner as has been done for liver transplant recipients.

Immediate postoperative management and complications on the intensive care unit

The postoperative management of patients immediately after liver transplantation requires knowledge of this complex surgery and the physiology that accompanies liver failure. A multidisciplinary approach to the care of these patients is essential in order to reduce postoperative complications and preserve function in the transplanted organ. By their nature, patients undergoing liver transplantation have complicated medical problems before surgery which must be borne in mind when managing them after surgery. Haemorrhage, haemodynamic instability, acute renal failure, hepatic artery thrombosis and primary graft non-function are some of the complications that clinicians must be prepared for in the first days after transplantation. Pre-empting complications and acting rapidly to overt them is likely to have a considerable positive impact in these patients.

Acute Respiratory Failure in Renal Transplant Recipients: A Single Intensive Care Unit Experience

OBJECTIVES

Frequency of pulmonary complications after renal transplant has been reported to range from 3% to 17%. The objective of this study was to evaluate renal transplant recipients admitted to an intensive care unit to identify incidence and cause of acute respiratory failure in the postoperative period and compare clinical features and outcomes between those with and without acute respiratory failure.

MATERIALS AND METHODS

We retrospectively screened the data of 540 consecutive adult renal transplant recipients who received their grafts at a single transplant center and included those patients admitted to an intensive care unit during this period for this study. Acute respiratory failure was defined as severe dyspnea, respiratory distress, decreased oxygen saturation, hypoxemia or hypercapnia on room air, or requirement of noninvasive or invasive mechanical ventilation.

RESULTS

Among the 540 adult renal transplant recipients, 55 (10.7%) were admitted to an intensive care unit, including 26 (47.3%) admitted for acute respiratory failure. Median time from transplant to intensive care unit admission was 10 months (range, 0-67 mo). The leading causes of acute respiratory failure were bacterial pneumonia (56%) and cardiogenic pulmonary edema (44%). Mean partial pressure of arterial oxygen to fractional inspired oxygen ratio was 174 ± 59, invasive mechanical ventilation was used in 13 patients (50%), and noninvasive mechanical ventilation was used in 8 patients (31%). The overall mortality was 16.4%.

CONCLUSIONS

Acute respiratory failure was the reason for intensive care unit admission in almost half of our renal transplant recipients. Main causes of acute respiratory failure were bacterial pneumonia and cardiogenic pulmonary edema. Mortality of patients admitted for acute respiratory failure was similar to those without acute respiratory failure.

Prevalence, Cause, and Treatment of Respiratory Insufficiency After Orthotopic Heart Transplant

OBJECTIVES

Heart transplant is the best treatment for end-stage heart failure. Respiratory insufficiency after heart transplant is a potentially serious complication. Pulmonary complications, pulmonary hypertension, allograft failure or rejection, and structural heart defects in the donor heart are among the causes of hypoxemia after transplant. In this study, we evaluated the prevalence of hypoxemia and respiratory insufficiency in patients with orthotopic heart transplant during the early postoperative period.

MATERIALS AND METHODS

We retrospectively evaluated the medical records of 45 patients who had received orthotopic heart transplant at our center. Clinical and demographic variables and laboratory data were noted. Oxygen saturation values from patients in the first week and the first month after transplant were analyzed. We also documented the cause of respiratory insufficiency and the type of treatment.

RESULTS

Mean age was 35.3 ± 15.3 years (range, 12-61 y), with males comprising 32 of 45 patients (71.1%). Two patients had mild chronic obstructive pulmonary disease and 1 had asthma. Twenty-five patients (55.6%) had a history of smoking. Respiratory insufficiency was noted in 9 patients (20%) during the first postoperative week. Regarding cause, 5 of these patients (11.1%) had pleural effusion, 2 (4.4%) had atelectasis, 1 (2.2%) had pneumonia, and 1 (2.2%) had acute renal failure. Therapies administered to patients with respiratory insufficiency were as follows: 5 patients had oxygen therapy with nasal canula/mask, 3 patients had continuous positive airway pressure, and 1 patient had mechanical ventilation. One month after transplant, 2 patients (4.4%) had respiratory insufficiency 1 (2.2%) due to pleural effusion and 1 (2.2%) due to atelectasis.

CONCLUSIONS

Respiratory insufficiency is a common complication in the first week after orthotopic heart transplant. Identification of the underlying cause is an important indicator for therapy. With appropriate care, respiratory insufficiency can be treated successfully.

Acute Respiratory Failure in Cardiac Transplant Recipients

OBJECTIVES

This study sought to evaluate the incidence, risk factors, and outcomes of acute respiratory failure in cardiac transplant recipients.

MATERIALS AND METHODS

Cardiac transplant recipients >15 years of age and readmitted to the intensive care unit after cardiac transplant between 2005 and 2015 were included.

RESULTS

Thirty-nine patients were included in the final analyses. Patients with acute respiratory failure and without acute respiratory failure were compared. The most frequent causes of readmission were routine intensive care unit follow-up after endomyocardial biopsy, heart failure, sepsis, and pneumonia. Patients who were readmitted to the intensive care unit were further divided into 2 groups based on presence of acute respiratory failure. Patients' ages and body weights did not differ between groups. The groups were not different in terms of comorbidities. The admission sequential organ failure assessment scores were higher in patients with acute respiratory failure. Patients with acute respiratory failure were more likely to use bronchodilators and n-acetylcysteine before readmission. Mean peak inspiratory pressures were higher in patients in acute respiratory failure. Patients with acute respiratory failure developed sepsis more frequently and they were more likely to have hypotension. Patients with acute respiratory failure had higher values of serum creatinine before admission to intensive care unit and in the first day of intensive care unit. Patients with acute respiratory failure had more frequent bilateral opacities on chest radiographs and positive blood and urine cultures. Duration of intensive care unit and hospital stays were not statistically different between groups. Mortality in patients with acute respiratory failure was 76.5% compared with 0% in patients without acute respiratory failure.

CONCLUSIONS

A significant number of cardiac transplant recipients were readmitted to the intensive care unit. Patients presenting with acute respiratory failure on readmission more frequently developed sepsis and hypotension, suggesting a poorer prognosis.

Percutaneous Dilational Tracheotomy in Solid-Organ Transplant Recipients

OBJECTIVES

Solid-organ transplant recipients may require percutaneous dilational tracheotomy because of prolonged mechanical ventilation or airway issues, but data regarding its safety and effectiveness in solid-organ transplant recipients are scarce. Here, we evaluated the safety, effectiveness, and benefits in terms of lung mechanics, complications, and patient comfort of percutaneous dilational tracheotomy in solid-organ transplant recipients.

MATERIALS AND METHODS

Medical records from 31 solid-organ transplant recipients (median age of 41.0 years [interquartile range, 18.0-53.0 y]) who underwent percutaneous dilational tracheotomy at our hospital between January 2010 and March 2015 were analyzed, including primary diagnosis, comorbidities, duration of orotracheal intubation and mechanical ventilation, length of intensive care unit and hospital stays, the time interval between transplant to percutaneous dilational tracheotomy, Acute Physiology and Chronic Health Evaluation II score, tracheotomy-related complications, and pulmonary compliance and ratio of partial pressure of arterial oxygen to fraction of inspired oxygen.

RESULTS

The median Acute Physiology and Chronic Health Evaluation II score on admission was 24.0 (interquartile range, 18.0-29.0). The median interval from transplant to percutaneous dilational tracheotomy was 105.5 days (interquartile range, 13.0-2165.0 d). The only major complication noted was left-sided pneumothorax in 1 patient. There were no significant differences in ratio of partial pressure of arterial oxygen to fraction of inspired oxygen before and after procedure (170.0 [interquartile range, 102.2-302.0] vs 210.0 [interquartile range, 178.5-345.5]; P = .052). However, pulmonary compliance results preprocedure and postprocedure were significantly different (0.020 L/cm H2O [interquartile range, 0.015-0.030 L/cm H2O] vs 0.030 L/cm H2O [interquartile range, 0.020-0.041 L/cm H2O); P = .001]). Need for sedation significantly decreased after tracheotomy (from 17 patients [54.8%] to 8 patients [25.8%]; P = .004]).

CONCLUSIONS

Percutaneous dilational tracheotomy with bronchoscopic guidance is an efficacious and safe technique for maintaining airways in solidorgan transplant recipients who require prolonged mechanical ventilation, resulting in possible improvements in ventilatory mechanics and patient comfort.

Long-term pulmonary infections in heart transplant recipients

OBJECTIVES

Pulmonary infections are life-threatening complications in heart transplant recipients. Our aim was to evaluate long-term pulmonary infections and the effect of prophylactic antimicrobial strategies on time of occurrence of pulmonary infections in heart transplant recipients.

MATERIALS AND METHODS

Patients who underwent heart transplantation between 2003 and 2013 at Baskent University were reviewed. Demographic information and data about immunosuppression and infectious episodes were collected.

RESULTS

In 82 heart transplant recipients (mean age, 33.85 y; 58 male and 24 female), 13 recipients (15.8%) developed pulmonary infections (mean age, 44.3 y; 9 male and 4 female). There were 12 patients who had dilated cardiomyopathy and 1 patient who had myocarditis before heart transplantation; 12 patients received immunosuppressive therapy in single or combination form. Pulmonary infections developed in the first month (1 patient), from first to third month (6 patients), from third to sixth month (1 patient), and > 6 months after transplantation (5 patients). Chest computed tomography showed consolidation (unilateral, 9 patients; bilateral, 4 patients). Multiple nodular consolidations were observed in 2 patients and a cavitary lesion was detected in 1 patient. Bronchoscopy was performed in 6 patients; 3 patients had Aspergillus fumigatus growth in bronchoalveolar lavage fluid, and 2 patients had Acinetobacter baumannii growth in sputum. Treatment was empiric antibiotics (6 patients), antifungal drugs (5 patients), and both antibiotics and antifungal drugs (2 patients); treatment period was 1-12 months in patients with invasive pulmonary aspergillosis.

CONCLUSIONS

Pulmonary infections are the most common cause of mortality in heart transplant recipients. A. fumigatus is the most common opportunistic pathogen. Heart transplant recipients with fever and cough should be evaluated for pulmonary infections, and invasive pulmonary aspergillosis should be suspected if these symptoms occur within the first 3 months. Immediately starting an empiric antibiotic is important in treating pulmonary infections in heart transplant recipients.

Late Intensive Care Unit Admission in Liver Transplant Recipients: 10-Year Experience

OBJECTIVES

We evaluated late intensive care unit admission in liver transplant recipients to identify incidences and causes of acute respiratory failure in the postoperative period and to compare these results with results in patients who did not have acute respiratory failure.

MATERIALS AND METHODS

We retrospectively screened the data of 173 consecutive adult liver transplant recipients from January 2005 through March 2015 to identify patients with late admission (> 30 d posttransplant) to an intensive care unit. Patients were divided into 2 groups: patients with and without acute respiratory failure. Acute respiratory failure was defined as severe dyspnea, respiratory distress, decreased oxygen saturation, hypoxemia or hypercapnia on room air, or need for noninvasive or invasive mechanical ventilation. Demographic, laboratory, clinical, and respiratory data were collected. Model for End-Stage Liver Disease, Acute Physiology and Chronic Health Evaluation II, and Sequential Organ Failure Assessment scores; lengths of intensive care unit and hospital stays; and hospital mortality were assessed.

RESULTS

Among 173 patients, 37 (21.4%) were admitted to an intensive care unit, including 22 (59.5%) with acute respiratory failure. The leading cause of acute respiratory failure was pneumonia (n = 19, 86.4%). Patients with acute respiratory failure had significantly lower levels of albumin before intensive care unit admission (P = .003). In patients with acute respiratory failure, severe sepsis and septic shock were more frequently observed and tracheotomy was more frequently performed (P = .041).

CONCLUSIONS

Acute respiratory failure developed in 59.5% of liver transplant recipients with late intensive care unit admission. The leading cause was pneumonia, with this group of patients having higher requirements for invasive mechanical ventilation and tracheotomy, longer stays in an intensive care unit, and higher mortality.

Critical Care of the Liver Transplant Recipient

Patient survival following orthotopic liver transplantation has greatly increased following improvements in surgical technique, anesthetic care, and immunosuppression. The critical care of the liver transplant recipient has paralleled these improvements, largely thanks to input from multidisciplinary teams and institution-specific protocols guiding management and care. This article provides an overview of the approach to critical care of the postoperative adult liver transplant recipient outlining common issues faced by the intensivist. Approaches to extubation and hemodynamic assessment are described. The provision of appropriate immunosuppression, infection prophylaxis, and nutrition is addressed. To aid prompt diagnosis and treatment, intensivists must be aware of postoperative complications of bleeding, primary nonfunction, delayed graft function, vascular thromboses, biliary complications, rejection, and organ dysfunction.

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.

Proposed management algorithm for severe hypoxemia after liver transplantation in the hepatopulmonary syndrome

The hepatopulmonary syndrome (HPS) is defined as the triad of liver disease, intrapulmonary vascular dilatation, and abnormal gas exchange, and is found in 10-32% of patients with liver disease. Liver transplantation is the only known cure for HPS, but patients can develop severe posttransplant hypoxemia, defined as a need for 100% inspired oxygen to maintain a saturation of ≥85%. This complication is seen in 6-21% of patients and carries a 45% mortality. Its management requires the application of specific strategies targeting the underlying physiologic abnormalities in HPS, but awareness of these strategies and knowledge on their optimal use is limited. We reviewed existing literature to identify strategies that can be used for this complication, and developed a clinical management algorithm based on best evidence and expert opinion. Evidence was limited to case reports and case series, and we determined which treatments to include in the algorithm and their recommended sequence based on their relative likelihood of success, invasiveness, and risk. Recommended therapies include: Trendelenburg positioning, inhaled epoprostenol or nitric oxide, methylene blue, embolization of abnormal pulmonary vessels, and extracorporeal life support. Availability and use of this pragmatic algorithm may improve management of this complication, and will benefit from prospective validation.